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DEPARTMENT OF COMMUNITY AND ECONOMIC DEVElOPMENT DATE: TO: FROM: SUBJECT: MEMORANDUM August 28, 2014 City Clerk's Office Clark H. Close, CEO Planning, x7289 Panther Lake Lot Line Adjustment; File No LUA14-000190, LLA Please find attached three sets of the above-referenced Lot Line Adjustment for recording with King County. Please have Champion Couriers take these documents via: Same-day service ($15.81)-10:00 AM deadline to City Clerk Attached is a check for the amount of $15.81 for the fee to Champion Couriers. According to Finance, the King County recording fees for this and all subsequent plat recordings should be charged to account #000.000000.007.558.60.49.003. Please call me at x7289 if you have any questions. Thanks you. cc: Yellow file Property Services Jan Conklin DEPARTMENT OF COMMUNITY AND ECONOMIC DEVELOPMENT M E M 0 RAN DUM DATE: August 27, 2014 TO: Official File / LUA14-000190 Panther Lake/Greenleaf Preliminary Plat FROM: Clark H. Close, Associate Planner SUBJECT: Principles of Acceptability of a lot Line Adjustment Section 4-7-0608, lists 3 principles of acceptability that the Administrator or designee considers, along with al/ other relevant information, when making a decision on a Lot Line Adjustment application. Check the appropriate box and give analysis, if necessary: D Correcting: Adjust lot lines including the elimination of a common lot line in order to correct property line or setback encroachments; Staff Analysis: Improving: Create better lot design, or improve access; Staff Analysis: The proposed lot line adjustment will reconfigure the lot lines between three (3) parcels (Parcels E-F). The proposed lot line adjustment results in a larger parcel that is proposed for subdivision (Lot A) and two smaller parcels (lot B & Lot C) along 108" Avenue SE (S.R. 515). Conforming: Conform to applicable zoning: see chapter 4-2 RMC, subdivision and other code requirements pertaining to lot deSign, building location and development standards. Staff Analysis: The proposed lot line adjustment revises the lot lines such that the parcels containing an existing single family residence may be segregated out from the Panther Lake/Greenleaf proposed preliminary plat (LUAl4-{)00190, ECF, PP, LLA, MOD). The subject properties are part of a collection of seven (7) parcels located on the west side of 108th Ave SE just north of SE 192nd St. The parcels have received preliminary plat approval for 34 lots which would result in a net density of 5.35 dwelling units per net acre. Lot sizes would range from 4,500 square feet to roughly 6,278 square feet with an average lot size of 5,318 square feet. In addition to the 34 lots, five (5) tracts are proposed for sensitive areas, storm drainage, and recreational areas. Lot B and Lot C become more compliant with the lot size, width, and depth requirements of the R-8 zone. Frontage improvements for Lot B and lot C would be constructed at the time of a future short plat application. Principles of Acceptability of Lot Line Adjustment I Sewall Wetland Consulting. Inc. January 28,2014 Rob Risinger Conner Homes 846 108th Ave NE Bellevue, W A 98004 27M1 Covinglm WaySE#2 Covington W A 98012 RE: Critical Area Report & Supplemental Stream Study Panther Lake Plat City of Renton, Washington SWC Job #13-204 Dear Rob, Phone: 2'i~15 Fax: 253-852-4732 This report describes our observations of jurisdictional wetlands, streams and buffers on or within 200' of the proposed Panther Lake Plat (Parcels #3223059148, #273, #344, # 123, #088, #080, #6623400054) located on the west side of 108th Avenue SE in in the City of Renton, Washington (the "site"). The site is an irregularly shaped 9.73 acre property containing five single family homes, as well as scattered outbuildings gravel driveways as well as large areas of lawn and ornamental landscaping. The site is located within the SE '/4 of Section 32, Township 23 North, Range 8 East of t}:l..e W.M. I~£C£I\!£ METHODOLOGY FEB 1 3 Z D 014 Ed Sewall of Sewall Wetland Consulting, Inc. inspected the site on c:ry OF RENT< December 3,2013 and January 8,2014. The site was reviewed usin~NNINGD/I/lsl ON methodology described in the Washington State Wetlands Identification ON Manual (WADOE, March 1997). This is the methodology currently recognized by City of Renton and the State of Washington for wetland determinations and delineations. The site was also inspected using the methodology described in the Corps of Engineers Wetlands Delineation Manual (Environmental Laboratory, 1987), and the Western Mountains, Valleys and Coast region Supplement (Version 2.0) dated June 24, 2010, as required by the US Army Corps of Engineers. Soil colors were Pant he r Lake /#13-2 04 Sewall Wetl and Consulting , I nc . January 28, 201 4 Pag e 2 id e ntifi e d using the 1990 Edited a nd Re vised Ed ition of the Mun sell Soi l Color Charts (K ollmorgen In struments Corp. 1990). The Washington State Wetlands Id entifi cation and Delineation Ma nua l and the Corps of Engineers Wetlands De lineation Manual /Region a l Su ppleme nt a ll r equire the use of the three-paramete r approach in identify ing and d e lineati n g wetla nds . A wetland should support a predominance of h yd rophytic vegetation , h ave h y dric soil s and di splay wetland h y drology. To b e co n s idere d h y drophytic vegetation , over 50% of the dominant species in a n area must have an indicator status of facultative (FAC), facultative wetland (FACW), or obligate wetland (OEL), accord ing to t h e National List of Plant Species That Occur in W etlands: Northwest (Re gion 9) (R eed, 1988). A h y dri c soi l is "a soil t h a t is saturated, fl ood ed, or p ond ed lon g enough during the g rowing season to deve lop anaerobi c condi t ions in the upper part". Anaerobic conditions are indicate d in th e fi e ld by soils with low c hromas (2 or less), as Panther Lake/# 13-204 Sewall Wetland Consult ing. I nc . January 2R, 2014 Page J d e termined b y using the Munse ll So il Color Charts; iron oxide mottles; h yd ro gen su lfi de odor and other indicators, Generally, wetland h y drology is d e fin ed by inund ation or saturation to the surface for a con secutive p eriod of 12,5% or gr ea ter of the gro w ing s eason. Areas that con tain indicators of wetland h y drology between 5 % -12,5% of t h e growing season m ay or may not b e wetlands depend ing upon oth er indicators. Fie ld indi cators include visual observation of soil inundation , satura tion , oxidized rh izospheres , water m a rks on t rees or other fi xed obj ects, drift lines, etc, Und e r normal c irc umsta n ces, indi cato r s of al l three parameters will b e p resent in w e tl a nd areas OBSERVATIONS Existing Site Documentation. Pri or to vi siting t he s ite, a review of sever a l n atural r esou rce inve ntory maps was conducted . Resources r eviewed included the National W etla nd In ve n tory Map, t h e NRCS So il S urvey online mapping and Data, WDFW Priority Habitats m ap ping website, a nd t h e King County iM a p website , King County iMap website According to t h e King County iM ap website t h ere is a Type F water (fish b earing stream) to the west of the s ite . This s tream is known as P a nthe r Creek. National Wetlands Inventory (NWI) The NWI m a p d e picts a stream to the west of the site classifi e d as R3UB (rive rine , upper perennial, unconsolidated bottom), Panther Lake m 13 -204 Sewall We t land Consult ing, I nc . January 28_ 2014 Pa ge 4 Above: King County iMap critical areas map depicting fish bearing stream west of site. \ SIn \ !>E I/I C- / . \ (O\--PV BH I-) \ p City of Renton Stream Inventory Panth er Lake/# 13-20 4 Sewall W et land Consul ting, I nc. Ja nuary 28. 20 14 Pa ge 5 The City of Renton Stream Inventory depicts a Class 2 stream (pink line) to the west of t h e s i te, a nd a C lass 4 strea m (Brown lin e ) a l ong the south edge of th e site. Soil Survey SE lB 5tll SI sr 18 6ih PI City oj Renton Stre am Inventory Map w en Q s According to th e NRCS Soil Mapper website , the site is m apped as Aldenvood soils between 6 %-30% s l opes. Aldenvood soil s are moderately well-d rained soil s formed under con ifers in g lacial till and are not considered a wetland or hydric so iL Pan th er Lake /#13-204 Sewa ll \Vet land Consult ing. I nc . Janu ary 28_ 2014 Page 6 Above : NRCS Soil map of the study area. WDFW Priority Habitats Acco rding to the WDFW Priority Ha b i tats mappi ng w e bsite , th e o nl y priority habitat o n or n ear the site is P a nther Creek (purple line ) to the west of the site. Panth e r Creek is d e picted containing r esid e nt c utthroat trout as well as coho salmon. Abo ve : WDFW Priority Habitats Map of the site. Field observations Uplands Panther Lake/#13-204 Se\vall Wetland Consulting, Tnc. January 2R, 2014 Page 7 As previously described, the site contains several single family homes and outbuildings located along the east side of the site. These homes have associated gravel driveways, landscaped lawn areas, as well as small pasture areas on the west side of the homes. The site slopes from a high point on the east down to a low point on the west, which sits on the top of a steeply sloped ravine containing Panther Creek off-site to the west. The majority of this sloping area is abandoned pasture and lawn areas dominated by a mix of pasture grasses induding orchard grass, tall fescue, bentgrass and quackgrass. Forested areas consisted of an immature deciduous forest canopy of red alder and big leaf maple with a dense understory of Himalayan blackberry, sword fern, indian plum, elderberry and stinging nettle. Soil pits excavated along the sloping upland area surrounding the wetlands revealed a gravelly loam with a soil color of lOYR 3/3 which was dry. Wetlands Wetland A Wetland A is a 7,744sf, slope-type, emergent wetland flagged with flags AI-All. This wetland is a disturbed wetland in an old pasture and appears to have disturbed soils from past plowing and grading. This wetland is dominated by a mix of reed canary grass, soft rush, creeping butter cup and blackberry. Soil pits excavated along the edge of the wetland revealed a dark (lOYR 2/2) gravelly loam with common, medium, distinct redoximorphic concentrations. Soils were saturated at a depth of -9" during our site visit. It is unknown if these areas remain saturated within 12" of the surface during the growing season. Panther Lake/#13-204 Sewall Wetland Consulting, Inc. January 28, 2014 Page 8 Using the US Fish and Wildlife Wetland Classification Method (Cowardin et al. 1979), this has areas that would be classified asPEM1C. According to the criteria in City of Renton Municipal Code (RMC) Chapter 4-3-050.M.1, Wetland A would be best classified as Category 3 wetland. Category 3 wetlands are defined in Code as follows; iii. Category 3: Category 3 wetlands are wetlands which meet one or more olthe/allowing criteria: (a) Wetlands that are severe~y disturbed. Severe(y disturbed wetlands are "'etlands which meet the following criteria: (1) Are characterized by hydrologic isolation. human-related hydrologic alterations such as diking. ditching, channelization andlor outlet modification; and (2) Have soils alterations such as the presence offill, soil removal andlor compaction ol soils; and (3) May have altered vegetatioll. (b) Wetlands that are new(y emerging. Newzy emerging wetlands are: (1) Wetlands occurring on top olfill materials; and (2) Characterized by emergent vegetation, low plant species richness and used minimally by wildlife. These wetlands are generally found in the areas such as the Green River Valley and Black River Drainage Basin. (c) All other wetlands not classified as Category 1 or 2 such as smaller, high qua/i(y wetlands. Typically, Category 3 wetlands have a 25' buffer measured from the wetland edge. Wetlands B, C, D and E Wetlands B, C, D & E are emergent wetlands which are similar in character and appear to have evolved in disturbed soils and are dominated by low plant species richness consisting of invasive plants. Wetland B is 1, 198sf in size and was flagged with flags B1-B6, Wetland C is 274sfin size and was flagged with flags C1-C5, Wetland D is 379sfin size and flagged with flags D 1-D5, and wetland E is 996sf in size and was flagged with flags E1-E8. All of these wetlands are dominated by a mix of creeping butter cup and blackberry. Panther Lake/#13-204 Sewall \\letland Consulting, Inc. January 28, 2014 Page 9 Soil pits excavated within these wetland revealed a dark (lOYR 2/2) gravelly loam with common, medium, distinct redoximorphic concentrations. Soils were saturated at a depths ranging from -2" to - 10"" during our site visit. It is unknown if these areas remain saturated within 12" of the surface during the growing season. Wetland E is highly altered and appears to be totally supported by artificial water sources including a roof drain from a home and garage, a gray water drain from the home and a drain tile from a previous water line construction just upslope of the wetland. Using the US Fish and Wildlife Wetland Classification Method (Cowardin et al. 1979), all of these wetlands would be classified asPEMIC. According to the criteria in City of Renton Municipal Code (RMC) Chapter 4-3-0S0.M.l, these wetlands would be best classified as Category 3 wetland. Category 3 wetlands are defined in Code as follows; iii. Category 3: Category 3 wetlands are wetlands which meet one or more olthefollowing criteria: (a) Wetlands that are severe~y disturbed. Severe(v disturbed wetlands are wetlands which meet the following criteria: (1) Are characterized by hydrologic isolation. human-related hydrologic alterations such as diking. ditching. channelization and/or outlet modification.' and (2) Have soils alterations such as the presence offill. soil removal and/or compaction of soils; and (3) May have altered vegetation. (b) Wetlands that are newly emerging. Newly emerging wetlands are: (1) Wetlands occurring on top offill materials; and (2) Characterized by emergent vegetation. low plant species richness and used minimally by wildlife, T7lCse wetlands are generally found in the areas such as the Green River Valley and Black River Drainage Basin, (c) All other wetlands not classified as Category 1 or 2 such as smaller. high quality wetlands, Typically, Category 3 wetlands have a 25' buffer measured from the wetland edge. Streams Panther Lakel#13-204 SewaU \\1etland Consulting, Inc. January 28, 2014 Page 10 Panther Creek (ofT-site) Anther Creek is located off-site to the west approximately 70'-130', Panther creek is located in a steep sided ravine and is relatively undisturbed with good forested buffer areas, Panther Creek is classified as a Class 2 water on the City Inventory, ii. Class 2: Class 2 waters are perennial or intermittent salmonid-bearing waters which meet one or more of the following criteria: (a) Mapped on Figure Q4. Renton Water Class Map. as Class 2; andlor (b) Historically and/or currently known to support salmonids, including resident trout, at any stage in the species lifecycle: and/or (c) Is a water body (e.g" pond. lake) between one half (0.5) acre and twenty (20) acres in size. Class 2 waters typically have a 100' buffer measured from the ordinary high water mark. Stream A A small intermittent stream is located along the south side of the site. This stream is a narrow mud bottom channel that appears to carry primarily runoff from the streets to the eats of the site. This stream is classified as a Class 4 water in the City Stream Inventory. Per Code; iv. Class 4: Class 4 waters are non-salmonid-bearing intermittent waters during years of normal rainfall. andlor mapped on Figure Q4, Renton Water Class Map, as Class 4, Typically Class 4 waters have a 35' buffer measured from the Ordinary High Water Mark. State and Federally Listed Species Review During our review of the site, no state or federally listed species were observed on or near the site. A review of the Priority habitats mapping for the site revealed that there is no known use of the site by any state or federally listed species. Wetland Functions Panther Lakci# 13-204 Sewall Wetland Consulting, Inc. January 28, 2014 Page 11 All of the wetlands on the site are "slope type" wetlands, with varying degrees of disturbance, As slope wetlands, none of these wetland store or attenuate any runoff or flows, and in fact are areas where groundwater is perched or discharging on the surface of the ground before infiltrating on the lower edges of the wetlands, All of these wetlands are Category 4 wetlands using the WADOE wetland ratings system which scores the wetland on three main functions, water quality, hydrologic function and habitat functions, They score extremely low for water quality and hydrologic function and low for habitat function, None of these wetlands contain any of the complexities or unique features that are found in wetlands of moderate to high function and values, They essentially just meet the criteria of a wetland with little or no functional value, PROPOSED PROJECT The proposed project is the platting of the property into 34 single family residential lots with associated infrastructure, Due to the topography of the site, the storm water facility must be located on the west side of the property and is proposed in the southwest corner, This will impact Wetlands B & C. We are also proposing to fill Wetland E which appears to hydrologically supported primarily by artificial water sources. This will result in a total of 2,468sf of Category 3 wetland fill. As compensation for this fill, we are proposing to restore and enhance 7,774sf of Wetland A which is a total enhancement/restoration ratio of 3.13: 1. Per City of Renton Code 4-3-050.M.8; If wetland changes are proposed for a non-exempt activity, the applicant shall evaluate alternative methods of developing the property using the following criteria in this order and provide reasons why a less intrusive method of development is not feasible. In determining whether to grant Panther Lake/#13-204 Sewall Wetland Consulting, Inc. January 28.2014 Page 12 permit approval per subsection M2 of this Section, General Standards for Permit Approval, the Reviewing Official shall make a determination as to whether the feasibility of less intrusive methods of development have been adequately evaluated and that less intrusive methods of development are not feasible: a. Avoid any disturbances to the wetland or buffer; The site contains three small wetlands which the developer proposes to fill and mitigate for through the enhancement of Wetland A. Due to the topography and the steep slopes, the only feasible location for the storm water facility is on the southwest corner of the site which will impact Wetlands B & C. Wetland E appears artificially supported by various upslope drainage pipes and rains which will be cut off during the construction of the plat as well as extension of the sewer line from the north. Any development on the north side of the site to the east of this disturbed wetland will impact its hydrology so it is not likely to remain regardless of if it were impacted or not. b. Minimize any wetland or buffer impacts; To move the stormwater facility upslope to avoid Wetlands B & C would eliminate the ability to get storm water to the facility from almost half of the proposed lots. This would make the development of the plat not be financially feasible to construct. c. Restore any wetlands or buffer impacted or lost temporarily; and Restoration of this wetlands in this location would not be feasible due to the location of the impacts and configuration of the parcel and remaining wetland. d. Compensate for any permanent wetland or buffer impacts by one of the following methods: i. Restoring a former wetland and provide buffers at a site once exhibiting wetland characteristics to compensate for wetlands lost; This is not applicable to this site as no historic wetlands are located on the property. Panther Lake/#13-204 Sewall Wetland Consulting, Inc. ii. Creating new wetlands and buffers for those lost; and January 28,2014 Page 13 A total of 2,468sf sf of wetland will be filled. Due to the sloping character of the site creating wetlands is not feasible on this site . . As a result, we are proposing using the "out of kind" provision in the Code using just wetland enhancement as mitigation for these small wetland impacts. Under 4-30-050.M.13, Out-of-kind replacement is allowed under the following circumstances 13. Out·oJ·Kind Replacement: Out-of-kind replacement may be used in place of in- kind compensation only where the applicant can demonstrate to the satisfaction of the Reviewing Official that: a. The wetland system is already significantly degraded and out-of-kind replacement will result in a wetland with greater functional value; or The three small, slope type Category 3 wetlands are just small areas where topsoil was historically removed to expose areas where surficial groundwater is present near the surface. These small areas are covered with invasive species (creeping buttercup and english ivy). The functional value of these wetlands is extremely small, as previously described with essentially no hydrologic or water quality function and very low habitat function. One of these wetlands (Wetland E) appears totally supported by artificial water sources from a gray water drain, roof drains and drains that were placed when a water line was placed through the property years ago. b. Scientific problems such as exotic vegetation and changes in watershed hydrology make implementation of in-kind compensation impossible or unacceptable; or The fact that the site slopes with a gentle slope to the edge of a small ravine with steep slopes, and the fact the remaining wetlands are slope wetlands results in a site that does not work for creating wetlands which typically involves excavating out an area so it will hold enough water to create wetland conditions. To attempt to create wetlands at a top of a slope is not prudent as it could create a situation where soils become oversaturated and could cause a slope failure. c. Out-ot-kind replacement will best meet identified regional goals (e.g., replacement of historically diminished wetland types). Panther Lakel# 13-204 Sewall Wetland Consulting, Inc. January 28. 2014 Page 14 The use of enhancement of Wetland A at a 3.13: 1 ratio (526.'1 if Wetland E is considered a man-made artificial wetland) will enhance an existing degraded low value wetland, and create an area with a forested and emergent plant community with enhanced functional value, primarily by raising its habitat function. The minimal stormwater storage and water quality functions of these wetlands will be replicated with the stormwater system. The enhancing of Wetland A will provide an adequate functional lift (raising the W ADOE Category from a IV wetland to a III wetland) through enhanced wildlife habitat function to adequately mitigate for the lost functions of these small low value wetlands to be filled. Stream Buffer Impacts The proposed stormwater outfall will be directed to the west, off-site into the buffer of Panther Creek to allow natural runoff to continue to flow to the west. (RMC) Chapter 4-3-050.1.8b states that criteria needed for crossing of a stream or its buffer; 1. Criteria for Administrative Approval of Utilities in Stream/Lake or Buffer: New utility lines and facilities may be permitted to cross water bodies in accordance with an approved supplemental stream/ lake study, if they comply with the following criteria: (a) Fish and wildlife habitat areas shall be avoided to the maximum extent possible; and The proposed impact is just in the buffer and is at aright angle to the stream channel and outside the OHWM of the stream. The pipe will be above ground and anchored and then will go underground for a short section before the outfall structure. An area of 10' on each side of the pipe has been identified as the potential construction zone and restoration of this area will occur within this area of potential temporary disturbance. A Hydraulic Project Approval (HPA) will be submitted to WDFW for this outfall and will follow the requirements of WDFW. (b) The utility is designed consistent with one or more of the following methods: Panther Lakel#13-204 Sewall \Vetland Consulting, Inc. January 28, 2014 Page 15 (1) Installation shall be accomplished by boring beneath the scour depth and hyporheic zone of the water body and channel migration zone; or NA, no work in the stream or under the stream is proposed, (2) The utilities shall cross at an angle greater than sixty (60) degrees to the centerline of the channel in streams or perpendicular to the channel centerline; or NA, no crossing of the stream is proposed, The crossing of the buffer will be at nearly 90 degrees meeting this criteria, (3) Crossings shall be contained within the footprint of an existing road or utility crossing; and NA (c) New utility routes shall avoid paralleling the stream or following a down- valley course near the channel; and The new line avoids paralleling the stream or following a down-valley course as required, (d) The utility installation shall not increase or decrease the natural rate of shore migration or channel migration,' and The construction method and restoration plan should restore the stream buffer to a condition that will not increase or decrease the natural rate of shore migration or channel migration, (e) Seasonal work windows are determined and made a condition of approval,' and The work was conducted during the seasonal work window approved by WDFW for the stream crossing project, (j) Mitigation criteria of subsection L3c(ii) of this Section are met A mitigation Plan meeting this criteria (" Wetland Mitigation Plan-Conner Panther Lake" prepared by Sewall Wetland Consulting, Inc, will be Panther Lake!#13-204 Sewall Wetland Consulting, Inc. January 28, 2014 Page 16 submitted to the City, The restored wetland, stream and buffer will be monitored 4 times in Year 1, and once a year for 5 years as required by Code, If you have any questions in regards to this report or need additional information, please feel free to contact me at (253) 859-0515 or at esewall@sewallwc,com , Sincerely, Sewall Wetland Consulting, Inc, Ed Sewall Senior Wetlands Ecologist PWS #212 Attached: Wetland Delineation/Plat Map Wetland Rating Forms Wetland Data Sheets REFERENCES Panther Lake!#13-204 Sewall Wetland Consulting, Inc, January 28, 2014 Page 17 Cowardin, L, V, Carter, F, Golet, and E, LaRoe, 1979, Classification of Wetlands and Deepwater Habitats of the United States, U,S, Fish and Wildlife Service, FWS/OBS-79-31, Washington, D, C, Environmental Laboratory, 1987, Corps of Engineers Wetlands Delineation Manual, Technical Report Y-87-1, U, S, Army Corps of Engineers Waterways Experiment Station, Vicksburg, Mississippi, Muller-Dombois, D, and H, Ellenberg, 1974, Aims and Methods of Vegetation Ecology, John Wiley & Sons, Inc, New York, New York. Munsell Color, 1988, Munsell Soil Color Charts, Kollmorgen Instruments Corp" Baltimore, Maryland, National Technical Committee for Hydric Soils, 1991, Hydric Soils of the United States, USDA Misc, PubL No, 1491, Reed, P" Jr, 1988, National List of Plant Species that Occur in Wetlands: Northwest (Region 9), 1988, U, S, Fish and Wildlife Service, Inland Freshwater Ecology Section, SL Petersburg, Florida, Reed, P,B, Jr, 1993, 1993 Supplement to the list of plant species that occur in wetlands: Northwest (Region 9), USFWS supplement to BioL RpL 88(26,9) May 1988, USDA NRCS & National Technical Committee for Hydric Soils, September 1995, Field Indicators of Hydric Soils in the United States -Version 2,1 City of Renton Municipal Code \ " \ :cl 'I \ \~;~f~~~t~t~ , ·f" Jc_"'::"no~!"J, ~,--~ ,--f~----T',,' . ,_'I -1 / ,/ I , '( If' \ \1' I " \ I, " ' I I \ " "" _,_'-- I " \ \ \,,--"'~ I' _ F~-'r'" " , 1\ \ \ ~--\,-_\ -Its \ 1 \ " ~'I \ "1' ~"'_''"~"'"'' \ " " • \. "~tOJTUl'Ci \'\'~\\~Il[["'{"C",,'"' " I"" " I'" I" [] \~"~'~"""\"\\ " HER L...:..K£.\,_-",( '\ "\. \ , \ '. \ " p-" ",", , , \'\GARDENTRACTS ... ..,\ \ \\1 \ \ \ . '"O"",r, 11",1 ' '",,, "-~ \ .,' \ " I ,!.L'-""'",;,><-c-• ",,,.n'. \ '~I@,' \ ' '1=;'=P~lvr ' \ \, ,,;.,.,L'f"!"', " -Cl~ -/ <. r; l I ~~'I \ I ' '1 I I 'i: I I /1 I""f~ ;0-.,.. 1 I \ I ,,' \ Y , : , \ I 'i ( &"~f""" " ' I I / ,',1 \,' / i / I I '/ __ ,1-1",-\, . I, " iii '\ i I I,H . 1 1111"1 / ~'--+..,--\ ,,\ I I / i ,I I ,,', ',\ I. , I, : , I I, I , \ '1I1' ,1 1 '.,,1 ' \ I 1 \ \ \ \' .... _ 1 I l \ \ \ \ '" \ , __ _ I ! \ '\ I, 'I '\ \ " '--.... __ _ I ii', I ' 'I ",' I I YE <.IAYI &: CI<I !..IAN 32230S908Q A PORTION OF THE SE 1/4 OF SECTION 32. Twp. 23N .. Rge SE. KING CO .. WA 11 1 L ~ W , ~ -I-- I : ~ I o ' " "i :'n" " I ·1 ' I I, , .' 1 i , J_ .. _' : 'I"\-J~ , I I : I ! r ' _~ _ I ' I I I';'i' ."!", ~ I ,~ n lfoGEND SCALE: 1 40' CONTOU" INT""VA[ = ~ .. :::::~ ~;::, o~,:.':""" ~ (}, "''''''''''''''OC, 3 " ~ " c ." .. I";-,,~~--' ~;.: ... ~ ,? 5t ,., ~ B'IIM ,I !. II ~ h Ii!! j! w rf) ::.:: I UI « ~ ~ ...J E o E I CC ~ a: W 8 UI I ~ ~ I-~ o Z ~ o « (L ! , 5 PP-02 :0' 11."-.-< ! I , ! • l J J WetJnd _ Of DUIIlber WETLAND RATING PORM-WESfERN WASHINGTON vcnioa 2 -tipcbte4 July lOO6 kI m-e -.cy IIftd reproducibility UIlOIII-- UpdDd 0cI: D)8 "db. !he new WDFW cIdinitioQs for priority hlbifltl. Narn,ofwctl.nd(ifknown), WU'liNrJ E ~ C--Datoofm"v;mtL:J' -/'1 Rated by -4} &e ~'" . TrainodbyEcology? Yes_No_ Dateofninins __ SEC: TWNSHI> RNOE: IsSlTlRinAppcndixD? Yes_ No_ Map 01_ unl: Flgu",_ EsUm_ slze--1..'... 9 Y 1 F SUMMARY OF RATING category based 00 FUNCTIONS provided by wetllllld 1_ 11_ IlI_ N_V_ Category I -Score ::-70 Category n -Soon: 51..69 Category m ;... Score 30-50 CateRorv IV -Score < 30 Score for Wafer Quality Functions Soore for Hydrologic Functions Score for Habitat Functions TOTAL ICOre ror hDCdollS Category based on SPECIAL CHARACTERISTICS of wetlond 1_ 11_ Docs DOt Apply_ I Final Category (,hoM. tho .wp .... " .... .,. from obovo) I J V I None of the above Wtll!md Ram, Funa -wc:dcq Wabinpon _2004 vaIIiOil 2 To be UIed willi E.ooIosY Pabticatian. O4-()6.OlJ Wdland nam.:: ('4' IItl111bcf .J3 ~ c Does the wetlaad unit being rated meet my of tbe criteria below? If you answer YES to anyoftheqLICStioIls below you will nClCd to pooted the wetland lltlcording to the regulations regarding the special characteri!rt:ics found in the wetland For the of this rating system. ~documentcdM means thewc:da.nd is 011 the database. '1"Ive4tened f.7 Endangued Mimal specie3? For the purposes of this mting system. ~documentc:dn means the wetland is on the appropriate state daIBbasc:. No1c: Wetlands with State listed • ,_ _._. 0 __ ' SP3. Doe3 1M 1f't:tland Jmit contain individuou o/P,.iority speciu liskd by the WDFW fa the &IllU? SP4. Doe& the wetland Ifm',luwe 0 local !lignijiconce in additiOrlIo i16fonctions? For example:. the: wetland has been identified in the Shoreline Master Prosram. the Critieal Area, Ordinance, or in a local management plan Il& having special significance. To complete the nat part ofthe data sheet you wil171eed to determine the Hydrogeomorphic Class of the wetlandbging ,qted The: hydrogcomorphic classification groups wetlands into those that function in simibr way,. This simplifies the questions needed ID answer how wdl the wetland functions. The Hydrogoomorpbic Class or. wetland can be: determined using the key below. Sec p. 24 for more detailed instructions Q~~~ssifying wetlands. WctlandR.iWJ,Fonn -w--. Wuhittgton 2 .... ioa 2 UpcbtoII wilb new WDFW ck:fiDitiom Ckt 20M: Aagutlt2004 Wetland name« -" ~ a ... ifiuti.D .rWetiand Units in Western W .. bingtoa 1, A~ ~s in the entire unit usually ~troIled by tides (i.e. except during floods)? ~ . YES -the wetland class is Tidtlll'riIlp If yes. is-·the salinity ofthc"MIter during periods of annual low flow below 0.5 ppt (pam pet thousand)"? YIS -Preth .... ter Tidal Fringe NO -Saltwater-Tlchtl PriD..-(l,JituuiDe) If ymtr wedQlld CdN be clouifrd Q3 a Fn.MwaJer TidD1 Friltp JIM tlMfomu lor Rivma~ we,kmds. lfil is Sallwa1er Tidal Fringe it if rated as un Ertullrilf.~ wd/tmd.. Wetlands dlat were call1:d emwine in the first and ICCOndeditions oCthe rating ~em are called Salt Water" Tidal Fringe in the Hydrogoomorphic ClassifICation. EstuariD: wetland, w-ete categorized separately in the cadier editions. and thls separation is being kept in thi9 revision. To maintain couistcncy between editions, the tam "Estuarine" wetland is kept P10ue notc. however, that the characteristics that define Category I md II estuarine wetlands have changed (sec p. ). 2 the entire -wotland unit is flatalid precipitation is the only ~ (>90%) ofwatetto it. ~]~ swface waier runotl'arc: NOT sources ofwatcr to the unit. (}fO -go !O YES -The wetland class is nab If)Our wetland can be classified as a "Flats" wetland, use the fonn for DepressioDaI wetlands, 3. Does the entire wdland unit meet both oftb: following criteria? _1be vegetated part: ofthc wetland is on the sbol"C3 ofa body ofpennanent open water (witbodt any vegetation on the surface) at least 20 acres (8 ha) in size; .-__ At~ JO-il oftbe open water area is deep« than 6.6 ft (2 m)? <_~ YES-Tho wetlom! 01 ... is IAke-lIil1go <Lo<-......... > 4, Does the ~rc: wetland unit meet .u ofthc foUmns critwia1 ~wet1and is an a slope ($lop! can ~ "'" gradutJl). _The wam' .fk:rwt1llrouab thc.~ jn one: direction (unidim.;1imH!1) and usuaIl)'... _ comes from seeps. It may flow subsurface, as shcetflow, or in a lWIIIe without ~nctbanb_ __ The water leaves the wetland witboDt beiDg npounded? N01E; Sutfo" W4lo does 1fOl pond in Ih~.ft! ~ ofwedmtds uapt occosiorIa/1y in wry.flttOU MJd .thaDow ~ms" behind 1aowmoc.b (rkpremons rJn tISIUlIly <jft tlUmtelD" ,.~.tIeait-l~ NO ~ go to 5 Y~Thc Wdland claasiB Wecs.od 1Uti:Bs: F<lm; ~ wctlmn WuhinlJllm 3 venioo 2 t.Jpdmed wiIh new WDF1I ~ Oct. DJS -..2004 Wetlandllltttcotllwttbcr B ~, Docs the ~bre wetland unit tnl!et.U ofthc following criteria? __ The unitis in a valley. or stream channd, where it gets inundated by overbank flooding from that stream or river __ The owrbank flooding DCcun at least once every two yeaf!l. NOTE: 1'hl!: riverine unit can conlai1l Jep'l:~ that are filkd with )itaiM' when the river is noljlooding. NO • go to 6 YES -The wdland cl8SB is RlveriDe 6. Is the entire wdlard unit in a topographic depression in which water POnds. or is saturated to the surface, at some time during tile year. Thi6 _am that mry outJ~t, ijpreSlenl, islrigher than the mten'(Jt' of the w~dand. NO -go to 7 YES -The wetland class i9 Deprel!llonal 7. Is the et'Jtire wetland unit located in a very flat area INith no obvious deprcuion and no overbank flooding. The unit does not pond surface water more than II. few inches, The unit seems to be maintained by high groundwater in the area. The wetland may be dik:hed, but has no obviolJS natural outlet NO -go to 8 YES -1'he wetland clUJ is Depressioaal 8, Your -wetland unit.xmll to be difficult to classify sod probably oontains severaJ different HGM clasea. For example, 8CCp3 a1 the hue of a slope may grade into a riverine Ooodplsin, or a small stream within a depressional wetland hal a 2'.Onc: offJooding along its sides. 00 BACK AND IDENTD;Y WHICH OF TIlE HYDROLOO[C REGIMES DESCRIBED IN QUESTIONS 1-7 APPLY TO DIFFERENT AREAS IN THE UNIT (make a rough sketch to help you decide). Uso the following table to identify the appropriate cIUII to usc: for the rating system ifyoo have several HOM clall!les present within your wetland. NOTE: Use this table only if the class that is ruommendcd in the IICCOnd oolumn represents 10"1'. (II' more ofthe total area of the wetland unit being rated. [fthe area of the class listed in column 2 is less than 10-1'. of the unit; classifY the wetland wing 1be: class that represents more than 90% of the total ami, Slo£'C' + Riverine Riverine Slo +De ~oruoI .anaI SI + Lako-Lake-frio Depressional + Riverine along stream within bolJDdary Deprc8si.onaJ .±J..aIrc..ftingc ·anaI SaltWater Tidal Frinse and any other etas! offreshwater Treat as ESTUARINE under _om! weUands with special characteristics If you are unable Blill to detennine which of the abov(I criteria apply to your wetland, or if you have more than 2 HGM clUgeS within a wetland boundary, classify the wctI.and as Depn!"Mlonai for the rating. wctbad lUting Fonn -"II'edcrn Wuhblpm 4 _i0ll2 UpoUted lIriIb _"WDFW ~tiollll Oct. 1001 .........- Wc:tland IWIII!I or lIamber 13 s s 1 {'XII Wrltcal dfwJ ,,, d.wztiOII for .wrry 100 fl w",lmod t:O'Per}. and 1UrCIft;;'~ 1tOl grozd u rrtOWedamJpbtu are [)eJn9&-.. uncut. heIbaceous ycpl:ltim > 9O%oftho wetland 1m!. J:)::mM:l. unGUt, habacecus w:getItia1. > 1/2 of .area ~ of area lf40hral _tioa ~ ~ Aa_ YES ifyoo bow or beHcvc tl:tc:R-arc pdl1ltatll in 8fOUIld.W&ter or ooming into ftc ~md that would OCbtIrwise AMIuce waf« qualily in streams. labs or groundwater downgnKIicnl from Ibo wetImd. Nate whld 0/" fallowing cxmditiMI provtde tlwl(}ltru$ ofpo//MttZlftt . .A rmit.N,V /raIJe poIbiUmt1 cOMing from H-..wal 104l~6. bKt I2I'IJ' Itngl. «RIruwottldqualtJY (U oppommlJy. -Onzingia bI wed.nd orwithiD.l~Oft -Untremd sIormwala' di!OlCharJCI1o wetland -Tdlod fickls, IosBin& acolVcltatds within I~O fed ofM;tland -Residential, wbm IIf'CU, or golf COI.n6II are within 150 ft upslope of weIIlQld c ......... v~ ",\ i __ .$ Sp--..e. Io...,ttv--c "I Wetlalld Ibting Form -woA=nl W .. hiaJfOn. [[ wn10D 2 UpdJtcd with now '9.'Df'W i&Bfinit:ion. 0:&.2001 ...... lOO4 C> multiplier Wetlaftd _= or 1I~ 3- s the pa7ltl approprla~ for tM (stewu o[ piants ,hould'--tJuck ~nQflglt (",wally;' Jlain). or deme ~h, to remain .reef t/Ju1ng llIifaujJawl) D=oSD. \Q1art,. rfcId vegetation covers> 90% ofthf. II'C& of1bc w:::dmd. Dense, 1Ulalt, rictd Vogdalion > I (2 era. of ~Ifld D=nse, 1Dlcut, ri&id vegetation:"> 114 area More~ 1I4ofarea is grazed. mowed.. tilled t'Jtvegetatioo is SJ2 The slope: wetland !WJ srn.1I SUffice 100;;. orin area. YES S of. Don the lfetiaDd .. ..,-e Cbe oppommity to redut't _ points '" 6 c7~ Is lIle W8tillld in. ~pe position ...mere d\e r~on in ~ velocity it provides helps protect dGwtIsIrcIm property and aquUio resouroes fum I100ding or excessive MId/or erosive 0!)\\/51 Note wldch ojtJte following condili(!pu apply. -WeClUId hu :aurfacenmolflhat draifts 10. river or IIream. th.t las flooding probkm, -OCher. (APUWO' NO iftAe thal is ort the TOTAL· Comments 13 ~"troIkd bra reul'YOlr (e.g. wetlaMll a ,up Watlaod Rating FOrDI-'frCII1cm W .. hiqtoa 12 venion 2 Updllfed with lIew WDFW defiaitioor. Oi::t. 2008 ABguIt2004 =- multipliClf • ~ I Wctlnd __ 01' IIUIIltMr ----IS Mfin«J by Cowardln)-Size threlltoldfOf' tlDl!!h class II Yo t:ICN! or MOt'S" them IOU O{,,,. arlKJ tf_1dt u ,mallv than 2.5 acres. _""" ~""h SI;nbIsbniJ (area where sbrubsh.vc>:3O%«1Vc:r) --Forested (we»..were trees bayo:>3O% covet) If''ihe .",t heu Q /Utloed clal' clred if: The fora:tedolusbu 3 ootof.51tHtl (CIOOpY.lIJb...canopy, sbrubs, herbaceous, -moa'}P:IlUIId...(lOWJf) !hat cam gowr 20% wilhiD the forc8tcd polygoo Add the mo:mb«' of vegttlatiOll #nIdJln4 that quabfy. If yct4 have; MapdCOWlI'dIn~oa.- .-H~IIJ • slnJctures (If more ,- 2_ poinh -o4 poin1!." 2: poUlts -I regime has to cover MICrip/I()1U ofhydmperiodJ) (Irydropttrlodl) pt'Uff'lt with"' the welkmd The wakT 1O'U o[,he tlllttdoM.u Yo.xP'e' to COflJl1 (IU ttxtfor Penruneody flooded or inundllted 4 or more types presmt --ScrucInaI.ly Roodc:d Ql'ullmdatod 3 types In'*It ------.....J)ccui<mally Hooded or immda10d 21ypes preseat _or Satunted ooIy llype prescu.t --Pammcntly (lowing ShIm or river in, or adjacent to. the wetland -SeasooaIlyHowinB I1fclnI in. oradjllCQ1tto, 1bcwetlmd pointll-"3 _-2 point'"' I poiats-O --~wbad -1 point. .' Fra .... tidtIlwrdlad-Zpolnt. Map of hydmpHlods C> Richnetu ofPlmt Soecies the wat\anddmtcovu at lcast Io-~. (4If!'-nmlpatchtn oft"" SQIIH ~ can be combined to rrru.t tn, stu threshold) r au do 1IOt have to ~ rk IptJCitU. Do not UtdIMls ~an Mil/Oil, rud cmtarygIWl. purp/M loousrrlfo. CanaJum. Think If you counted: :> 19 spcQe' points '" 2 Lilt sp«:iu bttkM tf)'Qllwam 10: S· 19 species pointlI-1 Wetland Ratins Fonn -wcdln. W..ttiasmn 13 vcniotl"2 Updated with ftIII'III' WDFW cWinitiom Oct. 1001 < S sp8Ci.ers points .. 0 Total for page _ -"'" C> C> Wetland IIIIDC or number R H 1.4.lutmpcnjQD ofb.hit"",-j$Uj-76) fl(pno_ Decide from lite diagrams below \\hefber intersperstoo. bctwI:en Cowardin vegctatioo ~5(dc!cri.bod in H 1.1), or the classes and un~tedarCfl$ (CIID iru::lude ClpM waf« or mudflats) is bip. medium. low, or none. 0(o)CIi:>@ ~ Low-I point Modcnto -2: poinls --~ / (riparian brakkd cl!annds) "':3 points NOTE; Ifyau have fuur (l[" m~ cluses or 1bree vegetation claues and opeD water the!!!in& is aIwav "'high". Use mlP f;ACowatdIn ~n cInses H 1.5. SI!'3ii!' Habitat fetturM· (lIUp. 71) CMct the /l4bttatf.ature: that are pTVlePII /11: the Wtllalld. TM ".,,,,bitr of checb b 1M ./ nwtIM of poi1lU ~ p141 into lite MrJ co/lUfm. _"'_ 'lMge. downed, "M>Ody cIebris wilhiD tho wctlud (>Cia. diamem-and 6 ft laog). __ Standing: !nass (dillllder at "\be bot1rJm :> 4 indtcs) in the wetland Unikmat banb arc pro_t for at leas16.6 ft(2m) andI« ovtlritangin, '¥Cgetation mdel'tds at --Icut3.3 ft(lm) 0YCfl. Jtream (or di1cb) in. or (lOOtiSUOU' with 1114: unit, b at least 33 ft (10m) __ Stable rrtocp banks of:fine metcriII thIIl might bel usod by boa"Gf or mu!daa.t fa donning (>3Ode:Krcc slope) OR signs ofnx:cnt beeva' activity lite present (cur shrub! or trus that have tWt }'oJ' hU'PJed gre}Ybrow1t) __ At least y..am: oftbin-stmuned pcnilteol vogc.talim. (l(" woody bnlndt4::!i an: pI"C!lCnlin IIR:IIS that are pennanenUy or !eUOM.lIy immclatrxl (Jtt'UC'l'IIru f(X" ~layIng by arrrphJbiall$) __ ID'Iuivc pJ.J!.w oovcr lculban 2:i% of1be MtIaud ua in each stn.1Um ofp1mts NOTE: The 20" ItatedllJearly prirstl~ofthema.m/.a1 rmpage 78isan crror. o H t. TOTAL Scoro ~ potential for providing habitat i I Add the 8COt'ftS from Hl.l, H1.2. Hl.3, HIA. 81.5 l ____ J Cornnteoh W~ Rims Fonn -wwWmWuhiop,n ... venicm 2 lJp<tMcd ""ith new WDFW definitions Cd 2001 ........ - Wl!tland MIII<t or_her H 1. Does the wetland IIrt1t .. ave the opporrunhy to provide b.bltat for maD}' species? H 2.1 DYJGn (ue p. 1O) F""",_ Choost! the "scription tMt be" "'pre#n~ CQrJitiafl ofblljfer ofW<llkurd IUdt. The Inghur scoriwg criteriOtl that applJeJ to 1M wetland is 10 be 'UN In lire rotIIrg. S" t~ lOP' definitton of Nrmdilturbed .. -100 m (3300) ofrdativcly undistuJbed vegetated areas. rocIcy 1tI"OU, or open -'or ::>1)5% of ciraunfOl'8ftCO.. No structures are YIithin llhtluodistwbed part ofbuft'er. (!'datively Wldisltrllod also means ~ 110 laadlceping, DO daily humen U~) Polnts-~ ~ 100 m (330 ft)ofrcl«livalyUDdisturbod wgotaUd areu,rocky.us. ttopcn ~~ SO% circ:umference. ~ -SO m (I 'TOft) of relttivcl.y IllldiltUrbcd ~gcta1lod arou, rocky ereu, or opcII % citwmfercooc. .......-. -100m (3300) ofm.tivoly lJDdillu!bcdvogetlted IrCU., rockyU'e&, or open water::> 15% cin:umfereocc. . PoInt.-3 -50 m (110ft) ofrelativcly!llldistwbed vegct&b:I areas, rocky U'OIU, or opciIl waI« fa ::> SO% circum.ference.. PoIntr;-3 Itbalfer does 11M IIII!ld UIi1 of the erttert. .how -No paved arcu (0XDilpf paved traili> or buildings witUn 25 m (110ft) ofwetl.and;;. 9~o;" cirwmfercftce. LiPt to naodcrat: BRzing. or taWllll are OK.. ....... -. -No paved arcu «buildings willlill 50rn of wetland fur >50% ciraJmferaoce.. Light to moderate grazing. Qr la_ are OK.. PoW.-! -HCIl\'Y snz:ma ift buffer. ...... -1 -Vcgelatedbufl"an Ire <2m'wicIe(6.6ft)furmorothlll9S%oftM ~crcm:c(e.g. tiHcd field!, paving. bualt bedrock extend to edgIl of wetland Pelnts-G. -Butrer 4k.a DOt IJlCI!:t my of the aiteria above. ~ ~ I ....... -1 '1 hltll photo ~ H 2.2 Cqrridsn .. 4 C'!P""9'imn (s« p. '1) H 2.2.1 Is the MfI.m;I PII1 or. rdUivcly undislurbod MId oobrokcn ~1Iod conida (either ripuim or uplmd) 1bet is at leall J SO ft wide. hu at lent 30% COWl' of shrubs, fCRSt IX natiw undil1Wbcd prairie, IYt UlIlJJt.)Cfs 'ID estuaries, other WdIands orundisturbod upland3lbat are ill l.east 2SO acres in size? (c:faIIu In rlparlmr co""='r.t, huJvlly tuetigrarNl roads, paved roadt. tJr6 comldend breob ill the cwridor). YES" .. paint. (go to H 2.3) NO" go to H 2.2.2 H 2.2.2 Is the MtIm4.,..-t of a m.tively uadilbubed and IJIlbr<:bn wpab:ld cmidoc (eitbcrripuian a-upIIIDI) lIWilatlcur 50ft wi., buat lent 30'".4 cowrofsbrnbstt fotest. and comects 'ID ~s, other wetlmds <II' UDdi5turbcd .pImiI1hat e:re Ilt last 25 IICI"OS in ~u? OR. r..ke-'I'rlIIct ....,nand,. if it doer; not bave In undis&urbcd oorridor is in IhtI quesUoa above? YES -2 p:lbta (gu 10 H 23) NO-H2.2.3 H 2.2.3 Is tbe WIrtlm4: willlin': mi(8km)ofabraGcishot SIlItwaterostuaryOR """"""--wiII:!id 3 miaralargc fdd IX pldure (>40 ~9) OR I ~ I mi of a ~ grcmr titan 20 tKlm!I1 0...-NO Total for pa8CI~ WetlmdIblm(Form-weQen Wa&laiBgton IS vcnioll2 UpdIIod wiIh l1li'91 WDFW ddiaitiOIII oct. 'lOOt .... -,.... wctlattd _ or rttn;bcr H 2.3 ~j tooibrzoriaityh.bjtllll-fj#od bvwDFW (uelln'.,.d~t1111Pki4 dampnoutl/WDFWpWrityA ... , .w611C8mllio ill wIIidr tireyctR klowul, in 11141 PHS report h«p.:/JtrtIIir WI royIh"""*4s' btmJ Which of1hc following priority habillU are wilbin 330ft (100m) of tile wctluu:I unit? NOTE: rhe conntct1onJ do nol have to be relatively undiJftlrbed. __ Aapat Stands: Pure 01' mixed stands of a.spr;o greater thlll 0.4 ba (Iacrc). __ BlodIl'ft'Sky AI'ftlIUUI Corridon: }\feU ofbabital tIlatare: Riatively important to verious speclesofnative fim IIlJd 'llr'ildlife(foll dltscrlptioru in WDFW PHS nport p. 151). ~rtJaeeoua o.lds: V uiable size patcbeB of wus and forbs on dlaUow soils OYer bedrock. __ OkI~taft ItJrests: (Q!d1lOWtb _t gfO'rw'; qsrtl StandlJ of It least 2 tree spoQel, Conniftg a muUi-layc::rcd canopy with oecalIional. small openings~ with at Ic:ast 20 tree8Iba (81rcc11acrc);::. 81 em (32 itt) dbh or > 200 years of IS¢. f'Mahtn:! rtlJ!R) Stands with average diametcn CXllCCdinr; 53 em (21 in) dbb; Q'O'MI: cover lillY be lcss1Mt tOO%; crown (lOVCIf JIl.IY be less. that 100%;. decay. decatJenec., numbers ofSllI8r., and qtlIIItity of large dolwed material iB ~ly leu fhIIIlhat found in okI.powtb~ 1O·200}'CUs ol4 west «the Cucade crest. __ ~ 'II'N~ Oak: Woodlands Stand! of pure oak or oaItIcmifer uaoclatioos where caP.qpy ~ of tile oak ICOIDporw:nt is important (foU MscrtPtiOlU tn WDPW PHS gt((;,t P. 158). ~ ... : Tha arm. Eljaecu.t ro aquatic systems wilh flowing water 1lW coataim clements of both aquatic end tcrreldrial ecosymms ~ lftUutty influCllcc cad!. oIbcr. __ Westside PrIIlrka: Hcrbaocous., non...fcnsted plant OOIDIIlUDitiOS that CoM c:i1hcr like the foon. ofadry prairie or I. wet prairie (fila <Uscr/.p(io1U in WDFW PHS ~rt p. 16/). _lIasIram.: The combination ofp;.ysical, biological, aDd cbcmical procc:!I5CS md cooditions tfW intend-to provide fuDctiODa! life: bi3tory ~uirClOu:ots for instroam fim aod wildJifo """""". _ Nal"lhore: RlIlltiveJy lIJIdisturbedneanhcn:: habitats. These includeCoutal Nearshore, OpeD. Coast Noaraborc, and Pogot SouDd Neersbore. (jiJ1 ducrtptit:ml ofltahitatr and the deji1fl!l.on o{n14r1.wly ultdinurbedare j" WDF'Wrcport: pp. }67·/69 andglosmryin A",,".'I< A). __ Cant: A naturally occurring cavity, roce5!J, void, a-system of intc:rtonnoctcd passages IInder dlc: earth in soil!,. r<:Klk,. ice. or other geological formations and is large enough to oootain a "'"""'- _C1If'fs: Groa!cl" 11110. 711 rn (25 ft)higb and. occurring below SOOQ ft. __ Tu.: Hcmogeaousveas ofrodtrubble:nutgingiD avllRgllli~ 0.15. 2.0m (0.5 _ 6.5 tt), composed ofbnalt, ~tc, MId/or lItdimCil.'ltary rock. induding riJRP :slides aad mine Wlitags. May be usocialcd with cIift'!. ~_ Srdp IUld Lop: T11lCS are ~ snap ifttoy uo dead CI' dying lad exhibit Mlfficient decay c:b~stic9 *> c:nIlblo cavity ~UBe by wildli~. Pricriry Atag$ have a diameter at breut height of> 51 an (20 ill) in "WeStern WasbiDgtOli. and are> 2 m (6.5 ft) in height. Priority logs 1Ift!;. 30 em (12 in) in diameter It the kg;. end,. and;;. 6 m (20 ft) .""". If_IIMd bas 3 orlMft priority llabi1atB = .. pointe If _IIMd bar. 2: priority habitats ,.. 3 points If wetland hIS 1 priaitybebillt-l point Nohabitm -0 poinb Note: All wgetatalW6rltuPds are b,Ydefinttton a priority habi/at bur are 1101 inr:luded in thtl lilt. Nearby weilanU are adJreud ffr({US3tion H 1.'fJ Weduld Rating Form -..-an Washinpm 16 wnion 2: UpoWcd with fII:W 1iIJI)fW dafinitionI Cot. 2008 ""...,2004 D Wetland name OUlumb« __ H 2.4 Wetland I-SCIRe (clKme the wre Wcriptioll oftha land&capuroumi tlw .... 'dtVld that wstftlri) (Rep. U) There are It lcut 3 alb« ~dands witin ~ mile, am iwI connectioos beMecD Ibern.-e reWivelyundistwbed (Jighl gnzing between \WtJmtb OK, as is lab: shore wUh!lOme boeting. but QOODC(;tiOfl3 tbovld NOT be bisc:cted by pA\'ed roads, fill, fields, ~ dwelopment. poinill - The-_dNJd i5 l..ab-fiinge on. b1cc with litdc distalbaDcc &ad thoro.." :} ather 0-' wetill1U "";dJin ~ mile poinu z 5 There III'i! at least 3 other wetlands within % mile, BUT '!be cmnoctiOllS betwceaI. them arc ........ poinll = 3 The wedand i. Lalce-fiinge 011. I like wtth dist\lrllance and th«c arc 3 other lake-fringe wcdmd witain 'A mile points -3 1"b:Irc i. at least 1 ~ within 'A mile. poiD1J -2 'I'b«e Ire DG -'landl within ~ mile. points .. 0 H 2. TOTAL Score 4 opportunity for providill8 habitat AddtMscoresfocm H1.1 H2.2 H2.3, Hl.4 TOTAL forH I frompqe 14 Toal Score for Habitat I'1uxtioas -add the points for H 1, H 2 and record the tetult on Wllltbnd 1W:in, Form -wedIlm Wuhiapm 17 _ioCI2 Updmd wih _ WDFW ddinitiOllll Oct. 2J)(NI p. J ...... - " _5 __ : .LL_: _L __ 12... Wetl.lftdn.meDl"lIumber 3 CATEGORIZATION BASED ON SPECIAL CHARACTERISTICS Please determine iftlre _lIInd _ the attriIJutes tk,aibed below ""d oUch th. IIJ'Fopriote an.rwers and Category. WdI$ocf:J:)pe.·. .'. .....,.... '.' .• . ~;,tr',i#y ~ rhilti!J>P1y ",Iii. ... tbin;:lC:lrc/>dNc:.t.py whmlhO .' .•. . ,. ;;i;Ii~-""I#it..-....... ···i. . ......... ..::c-", '. SC 1.0 r.m.riIle wetlaDds (su p. 861 Docs the weliand unit meet the following criteria for Estuarine wetlands? -Tbedominant water regime is tidal. -Vogetatc<l..nd -With a salinity greater than 0.5 ppt YES ~ 0.10 sc ].] NO - SC 1.1 Is the wetland unit within a National Wild1ife Refuse, NRtional Park, National Estuary R.c:K~. Natural Area Pre9Crve, State Park or Educational, Environmental, or Scientific RcIlCrVC designated under WAC 332-30-1511 YES-C .... ""'I NO ---'9 to SC 1.2 SC 1.2 Is dte wetland unit at least 1 acre in size and meeb at least two oCthe following thrw condition'? YES .. Cateaol')' I NO = Category n -The wetland is relatively undigu!'bcd (has no diking. ditching, filling, cultintion, grazing,. and has less than 10% cover of ~nativc: plant IIp<<lics. If the non-native Spanilta spp. are the only species that CQver more than 100M oHIte wetland. then the wetland should be given .. dual rating (I/TI). The area ofSpartina would be rated • Category n while the n::lstively undisturbed upper marsh with native species v,ould be. Category I. Do not. hoWCYCr. exclude the a.rc:a of 5partina in detcnninina the: size threshold of 1 acn:. -At least JI4 of the landward edge of the wetland has. 100 ft buffer of shrub, forest, or un-grazed or un-mowed grassland. -The wetland has at least 2 oCthc following features: tidal channch, dcpmlliOlls with open water. or contiguous freshwater wetiandL Wetland RAq Fonn. -WOItcm Wuhlngton 18 wniDa 2 Up;bred riil_ WDFW ddWtiODI Oct. 2008 <., Aupt2004 ~~. . . , Cat I Cat. I Cat. II 0..01 .. dB. lID Weiland IWIUI or _her _ A WI.TLANDRATING FORM-WESTERN WASHINGTON Vemou 2 -Up4atcd h., 2006 to inctcate tCCtIl'ICy IIftII R!p'Oducibility amotII uaetlI UpcbtDd. Oct 200S with the IlC'\II' WDFW dafinitium for priority hAiU. Namc: of wetland (ifknolNll): l,v.c....~ A DateufBitcvisit: Rated by Trained by Ecology? Ycs_No_ Dateoftrainini- SEC, TWNSHP, RNGE: IsS/TlRinAppcndixD? Ycs_ No MapofwretJand unit: Ftgure__ Estimated slze __ SUMMARY OF RATING Category blUed OD FUNCflONS Il""vidcd by wetland 1_ 11_ lli_ IV_./_ Category I =-Score :>~70 CaIcgory n -s.o.. 51.Q.l Category ill .. Score 30-50 CIt~Ory IV -Soore < 30 SOOI~ for Water Quality FunctiODS Score for Hydrologic FunctiODll Soon: for Habitat FWlCbOOS TOTAL ICOn !'or FunttiobS Category blUed OD SPECIAL CllARA9fERlSTlCS of wetlaud 1_ 11_ Does DOt AppIY_/_ &- Final Category ( ....... be "Jolgh"'" .... ,.,'" from ...... ) ~ WctJ.nd Rating Form - _ ... w .. 1tiftpft A£lau!It 2004 vcniott 2 To"" UMId wiIII:&ology Pab&aboa 04-06-02S -. i-. \ . , -" . " .. <t. 1'1 '" ! tv i WctJudnamcornumba-.A- Does the wetland uoit being rated rued any oftbe criteria below? If you answer YES to sny of the questions bclowyou will need 10 prokcllhewetland according to the regulations rogardins the 'peclal charaoteriatica found in the wetland. "documented" means the wetland. is on the TlrNfnIl!.d or-Endmrgu#!d tmimtzl $JH!ciu? For the pwposes of this [Bting~. "doeumentecl" means the wetland is on the appropriate Jtatc database. Note: Wct111U1ds IoVith State listed plant apcc:ies are SPJ. Doe.s th~ wedand llllil contain IndMJuab ojPrior-Uy sp&:ies liMed by Ilre WDFW.for the sla~? SP4. Does /he wetkutd lllrit Ikwr a local significance in tuIditiaJ to itsjlmctians1 For example, the \\/dIan({ has been. iden.tiflCd in the Shoreline Mastbr Program. the Critical Areas Onhnancc. or in a local management plan as To complete the nut part ofthe data sheet you will need to determine the Hwirogeomomhic Class ofthe wetlmul being rgted The bydrogcomorpbiQ classification groups ~andl ioto 1hosc that fundion in similar ways. This simplifies the questions nccdcd to answer bow well the wetland functions. The Hydrogcomorphic Chm of. wetland ean be determined using the key below. See p. 24 for more detailed instruc.tions on classifyin@;"WdJands. WctWldRatingForm-WCIUIm Wahington 2 vonioo. 2 Updated with new WDFW defutitionlo Od. 2008 AuglUt 2004 Wet1aad name or D.1InIIMr a ... ification of Wetland U.its in Western Wuhiogt .. 1. Are the water levels in the entire unit usually oontroUcd by tides (i_c. cxeep1 during floods)? NO -go to 2 YES -the wetland cla&8 ill Tid~ FriDge If yes,. is Ihe salinity of the wwtcr during periods of annual low Row below 0.5 ppt (parts per thotmand)? YES -Fresh •• tn Tidal Frinp NO -S"t~ ... ter Tidal Friqe (HiItuu1D.e) Q yoru wedand can be C'tuStf'iN oM a Frulrwaw Tidal Frin~ flU 1M fomufor RiHriIIe wetilmds.. If it is Saltwaler Tidal Fri"~ it is ,DUd 4$.:Ita Estallrin~ .,.dlond Wetlands that w«c Q&(I«I estuarine in the first and IICCOnd cditioos Dfthe rating system arc called Salt Water Tidal Frinse in the Hydrogcomorphic Classification. Estuarine wetlands were categorized scs-ratciy in the carlier editions, and Ibis acpantion is being kept in this revision. To maintain consisteM}' between editions, the term "Estuarine" ~and is .kepl PIcuc note, however, that the clwac:teristicllhat define Catesory I and n eatuarinc- wetlands have <:hanged (ace p. ). 1. The entire wetland unit is Oat and precipitation is the only wuroe (>90%) ofwaterto il Growdwater and surface water runoff arc NOT sow-ces of wakr to the unit NO -go to 3 YES -The wetland cllISI is nm If your wetland can be classified as a "'Flat&" wetland, usc: the form for DepftUioDal -. 3. Docs the entire wetland unit.eet botbofthe followingorit«ia? ~Tb:vcgetated pl.rt of the wetland is ontbcshorcs of. body ofpermanerrtopcn water (wilhoutan), vegetation on the s....raoc) at least 20 acres (8 ha) in size; _At least 3O'Aofthe open water area is deeper than 6.6 ft(2 m)? NO-go to4 YES -The wetland class is Lake-frinF (LaeutrfDe FriaIP) ... Docs the entire wetland. unit .. eet aD of the following criteria? __ The wetland is on a elope (slope can be "«rJ' grtJtlud). __ The water flows through the wetland iD OflC direetion (unidirectional) and nsoally comes from IICCpS. It may flow subsurface, All shcetflow. or in a IIwaic wilhout distinct banks. The water leaves the wetland wttboat beinc npouadcd? --NOIE: SIIl"Jau waler does 1tOt pond bllM.re IyJn ofwedands uc«pt occasioftally in wry 81M" tmd .s1taJlaw ~IN.uims a' behind lrummocb (~pns.siom an II.fNaily <3ft diameter and Ius than J foot mp). NO-go to S YBS-The wdland class is Slope WcdImd btifts POI1D -"IIJCdcm Walbina'on 3 wnioa 2 1Jpolbted widlnew WDFW dIIfiaitionI Oct 2001 _""4 Wetland umc: or IMllber 5. Does the entire 1O\-etlsnd unit meet an oftJ.e: following erileria? __ The un:it is in a valley, or stream channel, where it gets inW'ldated by overbank flooding from that stream or river Tbc overbank flooding occurs at least once every two years. NOTE: The riwrirw unit can cOrttDln tkpre.uions thdt are filled with water whe" the rive is I'IQ11flaoding. NO· go to 6 YES --The wrtIand class is Riverine 6. Is the entire wetland unit in a topographic depression in which water pomb, or is satulllied to the surface:, at some time during the year. This IMam that any auilt1t, ifp~MnI, i&higJter than the i1I~ritJl'" of1he wedand. NO -go to 7 YES -The wetland class ill DepR_loual 7. Is the enbR wctJ.and unit located in a very flat area v."ith no obvious depr~on and no ovetbank flooding. The unit does not pond surface water mote than a few inches. The unit !ICCI1l1l to be maintained by high groundwater in the arCIII. The wetland may be ditched., but has no obvioUS naturaloudet. NO -go to II YES -The ~ ~Iass is Depruslonal 8. Your wdland unit ICetJ1Sto be difficult loclassify and probably contains. sc:veral different HGM elases. For example., seeps at the base of. slope may grade into 8 riverine floodplain. or a small ~ within adcprcasional wctl.and bas a ZOIlCl oftlooding along its side!J. 00 BACK AND IDENTIFY WlUCHOF THE HYDROLOGIC REGIMES DESCRIBED IN QUESTIONS 1-7 APPLY TO DIFFERENT .AREAS IN THE UNIT (make B rough skctclt to help you decide). Use the following table to identify the appropriate class to UlII: for the rating 8yRem if you have 9Cvcral HGM classes present within your wetland. NOTE: Usc this table only if the class that is rcoommcndcd in the accond colwnn Iq'Rl3«I.U 10% or more ofttle total area oftile wcdaDd unit being rated, IfdJe area of the class listed. in colunm 2 isle8S than 10% of the unit; clusifythe wetland using tbcclus that rqm:sen.ts more than 9O-Aofthe total uca. Slope + Riverine Riverine Slope + Dopreooional Depressional Slope + Lake-fiinge Lake--fringe Depressional + Riverine along 8b"eam within boundary l)epressional reasional + Lake-fri sional Salt Water Tidal Fringe and anyolher ciBss offreshwaler Treat as ESTUARll'ffi under ...u.nd wetlands "With special -~ .. --~s.R.c.s If you are W\8.ble ltill to detennine wbieh of the above criteria apply to your wetland, or if you have more than 2 HOM clU9CIl within a weiland boundary, classify the: wetland I..!I Depressional for the rating. Wet1and.R.at.in.gFonn-w..taII. Wuhinglm 4 vtnioa 2 Upcbted with new WDFW clefulitiODl Oct 20011 ....... 2004 Wctknd _ OIlUIBIk .A Wetlmd RatiDSFonn-wClltera WahiDPJIl 11 wniou. 2 Upd.tcd wilhntl'll" WDFW ~ Oct. 200! I'" ·+·1.~-) ..... ',... Wedadn&JD~ornumbet A Chool6 t~ point: approprliZlefor 1m description (Iteml of plants sbld be rhicl mouglt (IlIValIy > 118m), or dfmse ~h, to rormafn uect rlw1ng Iwfauflows} Dm~. uncut, rtIId vegct1tion COYCnI > 90% ofthCl..ca of1he wetland. De.!.se,11rUlUt, rigid vegmtioo > 112 area of w«Imd ])cuse, uncut, rI&Id vogatation > 1/4 UCIl More ~ 114 of II"CI. ill wlUd. mowed, IiUed or vegetation is ~ points ~ 3 points -I 1bc slope ~ has midi surface depressi.cas that C&D rcIain wafer over at least 10-.40 of its area. YES poiDtll "'-~ ......... , ... it provides helps. protoct downstream P"0IKrtY and aqultic I'C3OOl"ClCS fimn Rooding Of" excessive and/or erosive Bows? Note which o/tIle foillMiI'lg coJtdtttons apply. -Wetland has surface nmofTthat drains 10. river 01' stream Ibat he 800ding ..... ,~ t4nswer NO if the thatUonlM jj conlTollsd by a nll~1'VOIr ~g. _tland j$ a uep TOTAL ~ Comments WctIaDd Rmn,Forrn. -~ Wuhinsfon. 12 vcnim 2 tJpdDcI with new WDFW ddiniUOMo Oct. 2008 ....... - '"' A- ~ c o ~ (.,. multiplier --L I. (,. WdIaDcIlYII1Cor_bCl' Il" _. 'lcla$s is % acr6 01' moNI rh<m lfJ'n of tIM Stu tlvu1toid/oreoch 2.j acrer. , JoIuati, bed / _-:7_'rm,,;-orgcat pJaa,b Seru!tlshrub (arcu \\tIrn= shrub.! have>3O%~) ./ =Forested (areas wbeto troc3 Mvo ::>JO% OOWI') / IllM IInitlnutr{orut«lclancMd: if _The be3toddeshu 3 OOof5 strm,(cuopy, sub.culopy. slJrubs,. herbacca1s. mosaIgrouDd-covcr) 1hat each CO"I'R' 20% wilhin the forested polygon Add tn. _ber of \.WgfiQlt01l !lr'IlctWnl rmt qIUlIJfy. If you have: "lIPaI'~~dHIe$ 4 IInII:tUres 01 more ,- 2_ points""' 4 polnb ~ 2 points "" 1 regt.IflBS (1tydropniodl) pumt willlt1f tha Wgtl~ The water reglWH '"" to coPel'morg thai/' ltm.o/IMwdlaMor¥. acNl toCOll.l'lt (866 te:xt/or dewrlptions f('1tydropet1od.s) __ PcnmmeIIdy flooded or inundated 4 or m«e types pro:saIt __ SeuooaIlyOoododormUIldakJd J types pte!ll'llrt ~ioaally flooded or immdaW 2 types ~ -:7'_"""SEun'nkd coIy I type presmr __ ParmlZlClntly ftowing m-n« riv« in. or adjacent 10, the wetlIiid __ Seasonally ftowiDg stream m. or "djaoeut to. the wedand . -- points '" 3 plintl-2 ~ RishnrM rifplplt sP!!IiP • ~ , Count tile number of plant spocic:!l in the wetland lhat cover J.t least 10 ftl, (rAfferent patcheJ of the nzre .fJN1CitJ, can 1M eoMbIned to 1fINt rlv stu rhrnhold) YOtI do #lOt lJave tonamtJ tM.rpect~. Do 1101 itrCllUk EtvaSltm M/lfoll. rr:ed ~.!', purpk Iotnutrifo. CaIJadz.:m Thilrk lfyoo counted: > 19 spocics poinlll" 2 Li.rt~iubUowif~wamro: 5-19species ~-I < S sJJCQics ~ ~ o c/ Total fot page __ WctbM 1tItift, Form -'111' __ WRkinatcm 13 vemOfl"2 UpUcd 'lll'iIb new WDFW dediaiticm. Ckl. 2(11}8 Allprt 2004 r..{r'1 J ,) Z- o 3 Wctbtld..me or number A Int«m:niOll of Dbitl" b« from !be diagrams below whether mtenpenion ~ CO\wnlin vtgetatiCRl ~laMCS (deK:ribcd in H 1.1). Of the chlSScuod WMlgetatedU'f:U (can iacludo open MV or mudflat!) i. high. modium, low, or none. 0C~@(jj)@ . Nate ... o· Low -I point ModerJ.k: = 2 pointll --~ / [ripuim braided ehannds] c:luses Old open WJ.ter dr. wf!lland. T1te ntllflbu ofCMcb is III~ _her of polnu }'OIl PJd inro lite M%t colll.lM. I _Large. downed. woody debris wHhin Ihe wetland (>4in. diamctw and 6 ft long). ,.....1'"" __ Standinl_ap (diamctor at the bottom::> 4 inc:bes) in. tbc wetland ,....-. r __ UQdcrcut banks ue preliCllt for at alit 6.6 ft (2m) UldlOI ovcm.nging wgotaIion exmads at lcut 3.3 ft (1m) 0'Y0r alllreaDt (or di1eh) ill, or contiguous wilh Iheunit, fel' IIlCUI 3] ft (10m) __ Stllble 5teop bUlks of fiM mate:rial that tni~ bo used by beaver or DUlsktar fer ~ (>3Odegrco slupc) OR :APJ ofra;enlbcaver Klivity an:: prcsc:rIt (cu/.fhruN or treru d!aI haw 1JQl yet tltmed grs)l"'brown) __ At 1!lUI '4 acre of liIm-stemmed pcnistcDt vcacQtion or woody brmeh~ an:: prc:scnt in areu that m: pcrtnUlCDIIy or ~ally inundated.(ItrndWrtJl for -sg-laytng by mnphibtam) _ Invasive plants cover Ies& 'tban 25% of the \oWl1and lU'Q. in each stratum ofplmts NOTE: 1M lOU .. t4led 111 _Iv pr(1f1inv oftlu! mtlJfll.m on Dal1t! 7811 an tJrror. H CommelltS Wetland Iatiag FcmI -Wedem W~ 14 VOflIW."2 Upddocl with lI8W WDFW 1kfioiti0lll Oct 2008 A_ptt2004 I"\. > k~J C> 2. Cl '---7 /I Wedand_eDrIl1llrlbcr H 1. Does the wetiaDd unit have the opportunity to provide habitat for maay lpedes? H2.1~ r-p.") F ..... _ Choou the delCtiptiQ1f t/tot best repnsen/I co1!ditiO/l ofbuff., ofwetland writ. n.1tt.gN!!ft seoJ'lng crU~Off thai appites to 1M wdlalfd i!f to be uud in Ihe rating. See tc;J for defi.nitlo~ rf ""ndUhtrW .. -100 PI (33Oft) ofrelatiwly undisturbed vegetated an:as, 1"Odty areas. or open watClr >95% of circumference. No!lb'UcttM'es are within the UIIws1Urbod part ofbufl'er. (rclativdy undidul'bod also means ftO-gI'Ei.D& no lUMbcaping. no daily bum8n us.e) ""'"" -, -100 m (330 ft) ofrelati\'eJy undiSCUrbCld veBGtaIed IftIIU, rocky aros, or open 'MlkIr ;.. 50% circumferc:nQC. PoIntI-" -50 PI (170ft) ofrdattvc:ly undisturbed Wge1liled InIIS, rocky area, oOr (lpM WIler >95% circmnf«enc:e. .......-. -100 m (330ft) or m.b\'ely undisturbed veptated arc:u. rocky arcu, or opcn. w.ter > 25% circumf~. PoInts-.1 -so PI (170ft) of relaJ:ively IIIldisturbcd vopll:ld areas, rocky anw,. « open walCIr for > 50% circumference. PoIntI-J U buller does not meet UV' (If* n1taIa ..... 1t -No paved ueu (exccptplMd trails) c. buildings widJin 15 m (IOft)ofWflfl~~ 'J circumfer"eoce. Lipt to modc:me: grazing. or lawns ere OK. Uobp -2 _ -No pam ueu or buildings wi1bin SOot of wetland for >50% circmnferalocl. Light 10 DlClIb.te I!JUin& or 1a'llr'ftS arc OK.. PofrD-J -Heavy .. &Ziog in butrCll". P1Iiru-l -vegetatad buffcn arc <2m wide:! (6.6ft) for more than 95% of 1be circutnf~ce (c.g. tilled fields, paving. basalt bedrock extc:nd to edge of wetland PeIPh-O. Z--BIlff« docs DOt meet lIlY of the cri1eria above. PaInh-l AlI .. 1 photo sfMMfna b!Jhts H 2.2. Cgnjdcg ad 0!n?1irn" (ue p. II) H 2.2.1 Is the wetland pat of arelativelyunclis1UJbcd ud uabrotc:n. vege1Ited COI'Iidl:w (citber riparian or uplmd) 1hat is .tleast 150 ft wide. hasl.t Icut3O% o:7VC(' 0( shrubs, forest or native undisturbed prairie, that CiCIMlCdJ 10 ostumel, oIber wdJlftdJ or uadisturbo:l upllllds hat WIll at least 250 acres in:hze? (~in ripariaN corridors. ~ly lLSedgravd roads. paved 1'O<ld8, ore coruJtXreJ br-eab tNI/w. CQn"l1hr). YES - 4 poWI (go to H 2.1) NO -go 10 H 2.2.2 H 2.2.2 Is the wctIaad pII1 of a ralativdy undidJrbed ud uabrokca voptated corri.cb (eith« ripatln or upland) that is at Iout.5Oft wide, bu at lout: 30% covet af!brub, or forMt. and ccrmecls 10 esbJarieI,. otbcr wetItads 01' uodisturbed upIaIm that ale It lcul 25 aaes in size? OR a Lab-frIn&e Wdland. if i1 does:DOl have an undisturbed corridor III in tile question Ibow;? YES-2po1n1s (gotoH2.5) NO-H 2.2.3 H 2.2.3 Is the 'MlIiaDd: witIli:a 5 mi (lkIn) of. btaddsh or salt water cshwy OR within 3 mi ora Wgc field 01' puttn(>40 IQfes) OR ~ 1 mi nf~tIwllO..nS,} YES"'l NO=OpoblCl Total for page 3_ WctWlil bting Form -'ll'CO:m WtIIhingkm IS ....... ioa 2 UpdItcd ~ ..-WDFW defiaitknIa Oct. 2003 _2004 , .-)-. ("" 2.. ....J WetlanclnmMOI'nlmM A H 2.3 Nearoradjicenttoo'!C:rnOOntvbebitats listed bvWDPW (_MW-IDIll~ tkscriptioastlfHJFW priDriIJ .. .,., "dI~ ~brwIJia\o tlrey ca kfoIUUl, in du PHS nport Me;/llwltW· wagr:1.tM:.' f:C hlm) Whicb oflhe fonowb:lg priority habi'lllts.are wi1bin 330ft (10lAn) of1he wctllOd unit'? NOI'E: the COIIRftClZOnt 00 ~r;1 .IJ.noe to be ~ly IlndUrurbed. ~".. studs: Ptml or mixed stands ofupeo greater !han 0.4 ha (I &ere). __ BIodIvenIty An:u and ConiIhn: ~ ofMbitat ht IrC relatively important to vviou~ spccicIsofDa1ive fish.wl wil41ifo(fiJlducripttons Irr WDFW PHS nporrp. 152), __ Rel'baceom Ba.Ids: VtWiabloe size pl.1cba of grass II1d fOrbson shallow !IOib over bedrock. __ OId~alul'r: rOftltI: roJd-smwtb wut qfC"S'd .. ctMf) Stands of at ~1It 2 tree species, fannin. a multi.fayered cmopy wiCb 0QCUimaJ small openiftg9; with at!Qs1 20 tI1:I:is/h. (8 trccSamI)> 81 em (32 in)dbh Cf"> 200 yean of age. tMatgre fa.) Stands with aYcngc diunaters OlIDfI(Id.ing ~3 em (21 in) dbh; t.TOv,u eow:r may be less that 100%; CI'OMl. COYernuybc lesstt.t 100%;. decay. dccadoncc.numbon; ofllllllS, and qlWttity of IarJc downed t:nItS'ia.I is gmara11y less 1han that fOund in old-gowtb; 10 ·200 years old ~ oftheCucade aest. __ ~ white Oak: Woodland, Stmds ofpute oak orOlkfoooil« U80cil.tiODs \Were ~ ..s-?'opy coverage oftllc 0Ik fi:lOOJponent: is 1mpor1lmt (foJI tX:crlp1tOM Sf! WDFW PHS /-.~e~p. 158). __ RJput ... : The area adjlOa:tt 110 .-qLIItl(; sysh:mI with flo¥ling w.ter tl:lId oonlairu elements of bod!. aqLJatic and tcm:sIriaI. 0C05}'"StmI1 whidJ ",ually iIlfIuenoe -caeb o1bcr". __ Watsldc: Pnlrla: lbob .. I' tlOIl.forcstod plant oommunities Ihd tall either take the foon of a dry prairie or .. wet prairie (foIl ducripfiOfl! In WDW PHS nport p. 161). ~rcun: The (;()!I1biaatioD ofphysica1, bioI .... md chemical proccISICS IUd conditions that inleract 10 provide ftmt:tionallife IDstoty requirements for instream fish and wildlife ,"""""", __ Nanhore: Relatively vndisUbcd n-sbore lUIbitats. Tbeso includa Coutt.I Nearshore, Open Coast Nemhore. aM PugeI Sound Nomhm:. (fof1 deJCripllmU ofhtJbillRs and the rJefi,tritionq{rel.atiw{y undi~au I1r WDFW rqorl: pp. J67-169andglanary in I.pp<nda A). _Cava:: A natumty oo;c;uning cavity. rooeB9, "YOid,. « sy7km of intenxnnec:lDd passages UDder the eu1h in 1Oib, rock. ice. 01' odI« plop formaliorl~ IUd is large enoogh to IOOQtain .. humm. _CIH&: Gteat« Ibm 7.6 m (lS tt) hiah and. ocamins below 5000 ft. __ y .... : HomogenausG"ceoCrockrubbJc ranginaiD aVCll"'q.l:l size 0.1 S • 2.0 m (0.5 -6.5 ft). composed of basalt, andesite, md'or ~ rock, iDcludirlg ripap slides IDd mine tmlings. May be UIOCialc:d with cliffs. _Sup and Lop: Trees are «lMidered snags iflley lI'e dead (If dying and exhibit sufficimt doc.y chlUClcris1ics 10 COIIble cavity ex:cavatio&lullCl bywildlife. Pricrily snags hve a diamdllt at breast height of"> 51 em (20 in) ill. westem WashingtOll and U'CI:> 2 m (6.:5 It) ift height. Priority logs are > 30 em. (12. iu) in diamClta" at the largest end, and"> 6 m (20 ft) long. lfwelland hu3 or more priorityhabitm - 4 poiId~ If -'Iud h!$ J priority habitats -J points lf1Wtland hu I primtyhllbitat-I polat Nobabihds" 0 points )Iou: All ~akd _tlands are by 4fonlt/On "priority hahrrat btd an not lrrciudui ill thi1 1m. Ih<rbv werJan<U are addre.ued In t1IIation H 2.4) wctbttd RatiftJ Form -'II'Cdcm WAhingtoa 16 wniolll2 Up4ltcll rih new WDFW ddiDitioJ1ll Oct. 2008 August2004 ,,+- \ WfIlbnd NIne or. __ ---D H H 2.4 Wetland J ""PM IclrooJe the (1M aucr/ptiOn oftlw Iantkcape arovndthe wnland dtat but fiU) (sup. 14) There 111'0 at least 3 other wetl.1Ilds within 14 mile. and flo COMeCtions betwccD. 1bcm lifO relatively Ulldisturbed (liBf\t grazing between \Wfllnd! OK,. as is lake sb~ Mil! !OIDe bo.ting. but c:oanectiotl.s should NOT be bisoctad by paved roads, fiU, field., 01' _~-« __ devclopmat. ~ The wedaxl is J....ak'e..fiinge on & l&kll wiIh IUde dUturbattu IIftd there 11'0 3 oIhcr late-fringe WdIlUlds within 'I. mile ,...,,-, 1'bere 111'0 at lout :\ other ~(Jand.!l within 'I.. mile, BUT the OlIDCCtioas betwoen IDem .-e ........ --, Tho "WCttand is J...ako..ftiDgc on a lake -.tch dirturbance and theft lite 3 oIbcr Jako.fungc -«land Mtlin lA, mile poinb '" 3 Tbcrc is at lcut 1 weaand widtin Yt mile. _-2 There are DO wedmdJ wi1hi..n % mile. _-0 "') H2. TOTALSc:ore-op~=:forprovidinghabilat '-1--. Addthucores Hll H2.2 H1.3, H2.4 1 _____ ' TOTAL for H I from page 14 Total Score for Hllbitilt FulXtiolU -add the poinIB for H 1, H 2 and record the result on ~~--- WotlandIWiDsForm-~W~ 17 _ion 2 tJpcbted with _ WDFW ddiailionI Od. 2008 0.1 -,,,.. C> --~-- -:J q 7 -J~ wctluld MmC or number h- CATEGORIUTION BASED ON SPEQAL CHARACTERISTICS PI"",. ddemrine if the _land _ the __ described below and cirde the appropriate /lIISWers ""d CatEgory. W~dJ:n>e' .... ..' ...•.. ...•.. . ...•• '~" Ch.;it;P#.~-ii}ifIJi"''''_d.. ~.iMC~;'h .. ,... . . ~ C.oegory ........... ~............ ..r .. >.·· ...... SC 1.0 Est .... rine wetlaads (sup. 86) [)oe, the wetland unit meet the following criteria for Estuarine wetlands? -The dominant watcr regime is tidal, -VogelAted. and ~ With a salinity greater than 0.5 ppt. YES = 00 to SC 1.1 NO SC 1.1 Is the wetland unit within a National Wildlife Refuge, National Park, NatiOMI Estuary Reserve, Natural Area Preserve, Snrt:c Park. or Educational, Enviroruncntal?or Sci.cntific Re~ desisnated under WAC 332~34)...151? YES -CatcRorv I NO ao 10 SC 1.2 SC 1.2 Is the "M:t1and unit at leut 1 acre in.ize ami I1lCct!. at least two ofthc following three oondilions1 YES -Category I NO -CatcsoIY n -The wetland is relatively tmdisturbed (has DO diking, ditching. filling, cultivation, 8JUing. and has less than lOY. covet of non-native plant species.. If the non-nativc SpartiIuJ spp_ arc the only species that cover more than 10% oftbe wetland, then the wetland should be given a dual rating (1111). The arca ofSpartina 'NOldd be rated a Catcgory II while the relatively undisturbed upper marsh with natiV\7 ~es would be a Category I. Do not, however. exclude the: area ofSpartinain determining the siz.e threshold of I acre. -At least 'I. ofthc landwatdedge of the: wetland has a 100 ftbufTerof shrub. f(l{$. or WI-graud or un-mowed grassland. -The"WCtland has at lcast 2 of the following features: tidal channcls, depressions with open water, or contiguous f~hwatcr wetlands. Wctla!ldRatin8F"rm-wNlimlW~n II VI\IIlIion 2 Updlllcd with rt1:W WDFW daiinitions Oct 2008 ......,2004 .' Cat I Cat I C.t II Duol ndn. 1111 PANTHER LAKE Preliminary Technical Information Report January 29. 2014 Prepared for Conner Homes 846-108 th Avenue NE. Suite 200 Bellevue. WA 98004 Submitted by ESM Consulting Engineers. LLC 33400 8'h Avenue S. Suite 205 Federal Way. WA 98003 253.838.6113 tel 253.838.7104 fax www.esmcivil.com RECEIVED FEB 1 3 2014 CITY OF RENTON PLANNING DIVISION January 29, 2014 Approved By: City of Renton PREUMINARY TECHNICAL INFORMATION REPORT FOR PAN11iER LAKE Prepared for: Conner Homes 846-10SIh Avenue NE, Suite 200 Bellewe, WA 9S004 Prepared by: ESM Consulting Engineers 33400 Slh Avenue S, Suite 205 Federal Way, WA 98003 01128/2014 RECEIVED FEB 1 3 2014 CITY Of RENTON PLANNING DIVISION Job No. 258-044-013 Date TABLE OF CONTENTS 1. PROJECT OVERVIEW............................................................................................................................................................................. 1-1 2. CONDITIONS AND REQUIREMENTS SUMMARy................................................................................................... 2-1 3. OFF-SITE ANALySiS ............................................................................................................................................................................... 3-1 4. FLOW CONTROL & WATER QUAUTY FACIUTY ANALYSIS AND DESiGN ............................. 4-1 5. CONVEYANCE SYSTEM ANALYSIS AND DESIGN .............................................................................................. 5-1 6. SPECIAL REPORTS AND STUDIES ............•.......................•......................•..........................................................•.......•....... 6-1 7. OTHER PERMITS ......................................................................................................................................................................................... 7-1 8. CSWPPP ANALYSIS AND DESiGN ....................•.......................•....•........................................................................................ 8-1 9. BOND QUANTITIES, FACIUTY SUMMARIES, AND DECLARATION OF COVENANT... 9-1 10. OPERATIONS AND MAINTENANCE MANUAL......................................................................................................... 10-1 UST OF FIGURES 1.1 Vicinity Map 1.2 Existing Site Conditions 1.3 Proposed Site Conditions 1.4 Soils Map 3.1 KCGIS Parcel Reports/Environmental Hazards 3.2 Offsite Analysis Downstream Rowpath 4.1 Pond Tributary Area Appendix A: Appendix 8: Appendix C: Appendix D: APPENDIX KCRTS Pond Sizing Output Geotech Report prepared by Earth Solutions NW Critical Area Report for Panther Lake, prepared by Sewall Wetland Consulting, Inc. Contech Storrnfilter Sizing Sheets 1. PROJECT OVERVIEW The proposed Panther Lake project is a 34-lot plat located on the west side of 10Stll Ave SE, just north of SE 192nd St, in the City of Renton. WA The project is 7.S5 acres in size and incorporates seven parcels numbered 3223059123, 3223059148, 3223059273, 3223059344, and 6623400054; and a portion of parcels 6623400050 and 6623400053 (these parcels will be divided with a BLA). All parcels included in the project area are zoned R-S. See Rgure 1.1 for the Vicinity Map. The existing site consists of 2 single-family dwellings with gravel driveways and associated outbuilding structures. All structures on site will be demolished. The developable portion of the existing site is moderately sloped (slopes between 6-15%) and slopes down generally from the east side of the property towards the west At the west edge of the property, the Site becomes very steep (15%+) and slopes down towards Panther Creek The pervious portions of the parcels around the buildings are generally lawn, while there is significant forested area on the west sides of most parcels. See Rgure 1.2 for the Existing Site Conditions. The proposed 7.S5 acre project site consists of 34 reSidential lots, 1 storm drainage tract, 1 recreation tract, and 1 open space/wetland tract All 34 residential lots will have new single-family dwelling units. The project area is zoned R-S and the lots will be 4,500 sf minimum in size. For access, the project will create a new intersection off 10Stll Ave SE at the north end of the project site. There will be a cul-de-sac on the south end of the project. Additionally, there will be an access pOint to 10S'h Ave SE created at the midpoint of the project site, through an access easement of the adjoining property. See Rgure 1.3 for the Proposed Site Conditions. A stormwater detention pond located in the southwest portion of the site will be used to meet the projecfs stormwater detention requirements. The water quality treatment will be provided by a stormfilter vault which precedes the detention pond. Additionally, there will be a stormfilter manhole to treat the bypass area in the northwest comer of the project. The detention pond will discharge to the west to Panther Creek, a well defined stream. See Section 3 for the Level 1 Downstream Analysis. According to the Geotech Report prepared by Earth Solutions NW, the site is underlain primarily by native soils consisting of medium dense to very dense glacial till. Additionally, according to the USDA NRCS soil mapping service, the entire site is underlain by Alderwood Gravelly Sandy Loam (a till soil), which varies from 5-30%. See Rgure 1.4 for the Soils Map. Based on the City of Renton's Row Control Application Map, the project site is in the Row Control Duration Standard (Forested Conditions) area. The project will be subject to Full Drainage Review per the City of Renton 2009 Surface Water Design Manual Amendments and the 2009 King County Surface Water Design Manual (2009 KCSWDM). The City of Renton 2009 Surlace Water Design Manual Amendment and the 2009 KCSWDM will collectively be referred to as the "2009 Surface Water Design Manual". The TIR Worksheet will be provided with the final TIR. 1-1 SITE VICINITY MAP NOT TO SCALE Figure 1.1 Vicinity Map 1-2 Agure 1.2 ExIsting Site Conditions 1-3 J=~PS T[~' ,IAf:;llf i> 'l~56':":""2~ I'.-'.,;;;;~ji'--,~;Z,~l;i~;-C I NIKI~I~~ ALA. C.::INc; 'liAL-E'< EE:F<OCI< LE.SUE M \ KENr CALVIN! CF<15DI'-tA .. , ... '/Alf~'I'-t A PORTION OFTHE SE 1/4 OF SECTION 32, TOWNSHIP 23N., RANGE 5E, KING COUNTY, WASHINGTON ~.'.C2 !, , ' I ~q"'E~IJ;)I~~ 59'iC'iClOO,)O v ._ , _" _ 8~~030~1;;O i<q,,:}'-C:Ol':1 32:::'0':>9202 /' .,~.f_HO -"v / ,e" ',' •• ~ ~"-,)"_~'33" ~ {"F;j; ".\ L_ 0"_1.;"'/>' !~ !l \ '\ \-"1 ,-~< I ..... < _"-1<3]7'<,\ ""''''-'~ '_~' -";'" ¥C __ '1""-i ---. ~ '::,r'") __ i --;-----_12" _ ~~'r..''''~'//~6' II I "'~.<l-:~ \',:,;;4:1 6-' -:c" """----~-'i::":'."·i5." .. 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I \ j' _\_ ~ I ' , '\, I.'?:. \ '. \ /.. \ ~\ \ r \ \ , oJ \, '\, .:." , /'l)' fA'y\.UNI f~ ~ NCRb'J 0-\ ,--EC~ES:J ~ ..1 \ "flY I»fl) R'" \L) ::\x -ji;;~; " \'1 \ "\ 11\11 \ ,\ \, m \, \ \ \, \ \ , '\ ' \ ' \ ",,j [-,HI I I)' \ '\(:u:\i(GCj\ --;-{t\\'-:~s v,-,~,,",," ~ o'~,'~ 2." , .." \ .':) <\I~--'\ 8'3":'·1'1-1" E \:'9-4 \ , , -1 <F~ l-"!, ' , \ " i', , ' 'i; \ , , \ ::...-~ -.-l I '-, "(rc,~ 'I I' ~ /1';-4/ / "1-'-,.-,_ <'./24" \, -\ '< IH/IS-\ .-----":;: , )J ! f; -~t{f,i':?r~,;~ " '---~. ·''''';t~I·'',_ '":- ,i ~< g , '1 \ \ -\ _I I .... \ --,--'-t \ ! I ,\1 J t\, , i I ' , I I ;]i"~ '1" , f ,I \ '''" " ': (;. ~ I II" 1\) J\ 1-1 .' '\ \ I 11"!_'l,.l." .'\ .. ""I :172 ,)-CA'Af-' \ , . ;1/ / '<i ! ---/ --/ i / ! /" / &_ ',1 xl" '. \, , 39'5,1" 7" 'ri \ 0/ .. \j· ) 5~5B 4~~ .. \(j C~~ IIi' , , ,1"°" 0',""' j I :;'. '~ ... c"'" '., 61 'I I ,H I!.,f ~~.''2\{. I,. -\ i Jr/ Ii i;!1/' ~;'\~i?r') , / ,<,v: -:-" hi/il lr, .' ! ".~~f#!1f.' I r I .' :1/.'// 2' r' -<) , /.:!//i/,'il'II'I,I'~:/' / ;;;;/.jl//.,' ,Ii c, / j/i'" II II,' 1'/1," ~! / ,fi/)lllllii /I('//,::r; "~' ? 1/'/;/')/.'1 ,,~.:"./~ "/z " .. 'V,i'l-, , i: \ .' ///,}-/.' .... '.(//.//:1;)// -I /)'/1,'///" ".'."1//;1 I !/~J-{i '~F-~; .;;:: )' .~\-;.. , ////:iill.,:','."\·':/?:·'· T -\~[-L/l~/ 1,11"11/11' 'i ' ; ... ..:::. J 1111'/,1/11111 '-: !, I' 1\ \il ','II, 'I' II \ I ,III \11,1 ,1, I _ 8/,;,.,/{r-i r;Avld ,,'-iL34'~1J:J7~ I LEGAL DESCRIPTION '''eEL A, J ! I / \, i ( / .... \\ \\ , ! ,/ i I L 'f '-, \ " ., \ \ \. " '. ;. , J 1 ~ .!.;L", """"""""-""'''''''''C' ,/ N 8'1 c·i)'II" I',' 422' 2' I \ \ / " / \ \ 1/ , , (I ",.. " " , j~! 1) , . ,< :>L'- \ Jo'i \ ., i----1 ( \ i i I' \1 ,~'\I: 'J\ \ [, I" __ .' --I II , -1 g-rl>{~~\-" :r'~"L ,U' T ,,' .~ r', -·-~:':~t~~<- " -, PARCEL E: _____ =--_t_\~-~ ~ :0' h I~" '-:;:-~'---. , / [-Wt!IAI',I!~~\\\ , ' -A~ -I, '-:2~~~~~,/iL/{<:'--;->\~ - "r::: ~::::M"j[ j,,/ '/ / --r ',0 11, / ".... < ,~~ c. -<'/-,1 ,--- 01,;' "I°Cth I . , I i I' 'oj ,\Nl -oF "'F",-"" fTFl 'F rHF "07 ;'0 ',fT U Y-., ',u~'" ~5~,j -[E' JC ~F -oF ',~RrrF"~r ~ ","-cR ~F n_, ~J_,T_.'.,c,T c;.,'R"o -,r S"C SeC 8', 52. :C"', "'c' 0' '" SOc '''[~sr r.UA~'C'" 0' ',E ",~',T'i~~S' ]}"R-:~ ")F .~, ',O~--iF:A~: J,-,AJ-' 'R Oc ·,·r ,c.,·'lwl"-Q.,'P1P J' VC' ;', ~;,,-~ ~A""[ c ',\,' ~'_, ~:n[ ,",,-"DM., ~ "f,G "':lJ~Tr ,IA-; !:"GT~~ C;,1L'~'N;-,,<, .. ,-r,, c. '_F --0-.. , --'~F" ,_, Fo',c; Y TH-5C,JH-",C,O FEET ~r T ,[ ,~~;" 'A_ Cr f C '>c"" "c'" ]'"AC'" c •• ,e '='1"'[A,-'l'A":R ;,~,,:':';:c~';.-:TH"";T CI'_AR' ~ C' e,C',C~ i;-, ")N'S-J'~ 2' ,0" " ",,~,;[ 5 ~~S' h',-".<["'[ '·E"'C'~'. ,~ ",G CCv',ry, ,\Nl -~. F.,,-'" ,,,T '" ,~, '" ,,' rl_,.O" ' ,r 0' -.'f ;CUfH ',,,,-,~~, r_r ,~,,'~',\fc,T ~,,,,~,,. F o"r. '-"_"C', ,;-: 'J' SJ_JT"[~5r ~vAo][" or ',,; '0""'['" ,',,"PT '" e,"- ',\JM~'R 7017'" C~,,", 'D'< "GA,; oJ"~C'c"o 9' ""_:~C;:: "C[P "[~J'e~G ,\~c: ,<CCO-'r_'-.-1\-' '-IF w,\C"~:;'C~ p, ~AR·",,"v eFF'! ,,:C~, IDE" "<~C-PJ'"C '" ~"'R "~-~,,,-,_,f, ,><'i -'r' "";T ~1 , FF[l '" [H' F'''' .'."J FFET n' 11,,. ~O'}l" ').: rTI • 'P,O" h~C) C,C,P! THe 'N>1 '2" rtc· '-)' '-if_ (I.;, ~" ... J"'" 'n,', • 0f r"r -,0' -< , 'c' 'tc '~lH,v h~a "COP' --: 'C~Tr ~}', ".c-1r·:4,~r .",~ :,~,PT -,: E'" '(I FEET T~,R,QF ,,' ',GW,y[(, 1" KI\~; ~J,~,Y r~'1 'nJ.,) ~",<F"O;"'-'V "",; "~O~-;f-, I ",)E" "ECC~~",C ,",.~B:R 7'0 I ,e,g "~D ,'C,PT ",,\T pa"-~~ Trl:~",' 'v~"y[(' --~: '-A-: GF 'iIA.H ,;'10'1 '>Y NARR.WrY ""'D RrC:'-,r-'-D ',N"),o ~,:O"},,', ',~E'" 7,('5:'10)', n LEGEND ,~~C[. ~~M{) -C> ·E~l;·")';l ~O_£ " fl~U ~~A'~_II~K ~AC, -E_E~~::~E 3')~D 'c' f"~~M )V,~Hf-AC W,\T~ Q " m H ,~i ",.'~A\" H]SE 81[j i'iATE~ ~A,~t: ' i;AII -, ','1 'r~ WATE~ ,',\_,'1: ..... o c @ APPARU-iT TeST rlT "~CAT,O>l~ o ~E~ uUu)~ ',ANI'~Rr ',''I<f~ ~~N~~l, S'O;;M IJR~I~ ~MCo: OASIN ,-:;F<f,/ DRA>~ ~~~~Ol[ H~)fJf ';R~'~ " CAS ME-:" SCALE: 1"_ 40' o ~_AC. 'IAL"[ 40' "':;'0' -0 40' 80' " tl t:-"RI(J. M' H~ '* Q, s' '" ~ U * r:OI_'GLr,~ fiR (0'''':[' n'J,r[~ '~Ai 'I 'l'e'I'(', Po;\E~ "~LE • i_Co'1 1:1 f' II & I~:,'-; CONTOUR INTERVAL _ 2' o I'O\\E~ '~ll • 'oc-~K f"ll EXCEPTIONS FROM TITLE REPORT I S.Fl_fCT -J ,,', EA~E!,IE~T >0" ,lE~'HI~ THAN~M\,'v~ AN~/~'~ DI'>;~'8'JfI)" L'~[, 'ND PPl;R"~'~~'~ ,'~) TrE 'EO~, ""~ '-(hOIT~~, IHrl1,O, GF;AI-.-ED -~ P',GEI ',O'J~D P",W[R & "WT ;OI'l'AN' ~, C()N-AINH! 'N ,~~H,',~E~' ,l~0"lEl' ',~):R fiECCR)~G ~) 7-'CI<.i~iiY T'i, .Y,'II~'~ OF '·f,l) EASE~E"' IS JEPIC'EO HEREI~ 7 :;U1JCC 10 ~ '~S[V[~T rOR ~A"f~ "hE,S; '-Nll A""J"lMN',b AM, I'n rERM~ .~) ~~~D"I(o~S TrE"E')r ~",,"TD co S~G' ~-'l,~ ',.\i,', ,-",r, "EW,~ JISII>IC1, A 'i"~ICIO,\_ <:G~PORAr:ON A~ CO~IMJII) ", 'N~lh'UM,~' ~I~'UIW[') l,hO:" ~E:()f.r",( "),, ,,20-"-"2"1 ,I'W ','2("'1'12~' 1'1>' ,}:.\II')~ DC SAl] E>5EYGH " D,~CEO ... ERE.~ ~ '~r.-"c 10 i-J'< f~S,VfNT fG~ ~G'fS~. 'G"E';, ~,D ,'''l'',,-; A~L-' -H, fiECOQO t.G ~!) 2nI2~RC-q,,)(,,~(,o ,'",', .~~ '_("~lrI0"" HE:~,8' hS (O"T.lI~'C ," I~~-~ IM,~ -~EC,V(:F Q 4. '>LbJt~' 'u ~V"E",'~r,. ,'0'""'<),"". "brr,'(TrO~", ~E~ ',",-';, RE,ER"ATl8~'>_ EASE,'n'I~, EASE',,,,I f''10v ~.m.~, r.f~,rA; <":~--;, P.LJ I L,NG SE-~",:~ '01., ANP 'T~Hllf~l:' I' J..~'. E')' ~~"TlNG M.y ~[;,'l"A~" ',:f-I "l';H~"~"'. I' oW ~C.~JI~~ Bu-'lOT lMTD T(O TH~SE BA,EQ Uf'0~ ~.\C' r;EUG0~. SO, 501l'\L ORIE~IA"O~ F~~'!_Al ',I~I,!', ~'-J!IIi', 'i:AIU~ 1;\A'II,:"_ -i~~)I:A~ ""TIOr'~" 01'10" "NCE';TR'. OR ~))"CE 0'-1~'~01,l'. ,I', CORlr '" '''DLIOBLE SIA-, ~:~ rtD.:R>c _ ........ :X~;:PT If. T~' CXTFW n-1o[ ',~I') CJvrNA~1 OR ~Eo'~'C"O'" I, "clWIl'LI} ~y ~I-f'"\~~~c "~'h.:' fQ~'~ ~~ 'He "LA' 0, ".~ ~,~ .AK' ~~"L'E' ,,,,.<;T,, "E<:O~XD I~ "'_,JME 'J Y 'lAl,. "ACE ,', ;,-E' • .;[C1 ro CCVE~,'~I REu\TI~~ 10 ~AI~I:NIll"n 01 111:'\1) J.;r'liC~CH (;'-'~~A~.IIJ" ~",_, Ofd;~ "OY~O~L' E J[AV M~[' ELY' K L'~~(Y, HI., '.1"', Ie 'kc ~TMc 'x WA5H'~~TON, R,U:"~D "~c,R ~,CG""lI~'~ Nil ?J'HI 'O\n: 6 c,m"c:r.-10 C8;,NA~1 R'IAI'~C IC l'AI~Tf~",CE cr RvAf PPHl'A~~ '"l)N,AIN," ,~ ~fU ,~~., ~LAW<;!. 3".;[ OF W~;HI~GI(of,. ~[cORCE[,' "'DER RECO,'CING NJ !2':''''ll~1Ii o\J<J..lC' 1u A ~GVc~AN' ~lL'"~~ 'v ~',I~I>.",NCt Uf ROAC ADP~CA£h ~')'IlA'.c'; I', lOll] r'lC'~ AlfTfR1 ;", STAT' J' ,'jAS'i~C;TG~ R,CC~lfJ C~C'R ~,<:~~JI~'-: W iD~L")4l~ ~~E[". ft~ -Eo "P"'~" '~'''E ',,"I~-~ "~l ~!>.);,f,-"LVi',-N, ,"', "iIll, 3 ~uB"ECT T,) ~ (8"E~"NT ~;::l,lTlN~ ;C "A'~'[',INC, 0' R('hr, ."PP~()~[r ~()'nA'NfQ '" r.rD "O~ G,O"J, '. lAr-'~',J ",~ c'O'!~'" ,"bI~', n Hl "TAlc Of '#':'~'M:"VN. ~e';URL"O UMO,R 'E:CORr."~C ~,)_ '2Q8,~O~'4 .w-- ~ N~fC, cr ~~-'illE ';E'hAGE 'iY'i-(1l I)'"P;,TGN I<\D "~I~III~AAU qE~ORCEC ~~)(D "ECU"~I~G 'oJ 2'c·.l~,;gJCIr:<') 'I ~,) H' Vi" I~ ~~I} "i~~ ~'''J ~8'.i!i'IQ~\ 1HE~(U A~ CO~TAI~,(: ~ ~.,l','I,W'~T 1,-" ~,), fiCOQ'lFD "'Rfl~ ~U8-.ECT Pl ~M Oil A~j GA~ L[AS, .':IT" (G"A'~ T[~~S_ ';,"E,ANI', (~~,r.'II~", ',\0 "",~,:,,"J',' ' ",J~H-,~".~T"U~L~l '"lC''l'U '_'~_'L" OE:()R[;INC ',~, "'~:~25 '>')""~',' ,J ,. ~,'RC~~'" flN~' 9J.J A'-;f:U:'~I;'1 1'1 1...,,1", JII, II ~ J WO, t ~u" tN:,I8R ~y, G~S "C' ,,,,,,n., AS :oJ"ANlC " 1"--'UI.!'N' ~':'J~f!F'1 ,';,n'R ~F:ORL'N~ ~c. 2rJc,,,c~O~l.',,C"2 U-?c, ~'JI RPO~T~ I'RfI~ NOTES ~~o '{)!,I A~~ ~~,RLEY ,~(" ~ "~'\'; :,', 1 '-"H,llI;:S OTrER -~'N THCl,E S,oJ',\~ MA" EXIST J~ r~[ SIIE, u~O"K;10l",r. "',,,lY 'r-,rA1IJ'" S IG"~ '-E~O~ APE 'AK,-~ -,')", A COMI'I.A C~ ~' PU6UG "eLl,Hl"_" J~)l~'~"~>JNJ l.lIl'-' ,~,;Ale',. I.IAP~,,~ " 8-r~S, D"~"JE:' 'Q E51.!~· ~LENT, ,\~J "ISlalE rl"_G 'VIJr~~" 'v ~~".M' ~O I'P,,'" 'OR 11<1 A~r:I.I1AC':) 'til ,'tHle H";C':~" ';p MA~P'~G ~U,j( PR;Of< 10 (01,/'" ~I!~''E'' Y IHE ')lrE LJ~),RC~OI_'~'C ~fl'----_'X!.T'~~' ',fiE S~,L' ,\P~'~~"~I.lF:, U~"FRSP,~'N;' (,O~~,r]O~S ~m ';·'G'\~ AS '"TR~IG ... T LI~_~ U[T','LlN V.,Ull ~J""': __ ')l'MI~'b cU' ~.Y cc,n'~ B",C'; C", • ~,,[, 5~C'li~ FIELD ,ERI'I(,\T'O>l S N,CE~S/l~Y P~'O' '~ ,1R OLR fJr. A4~ ~C>NC-~,ICn()N 7 II ';A III ',(;111'1 eN. I ~'" ML~I', C0'1' 'IA"lS (r;NDI1'Q~, <'W ~£SlR (-O~, A~c ,R8V C<"'~ A~'0;~;~~:;:,::~;:~~tCi:;~~ ';/;';':~0e!: C;, r,I1/1R"N"',!rp11"f~l, \0, .1U27N_I)<', JATED NC,'KBo" 22, ~J' j "'''veJ_') ['l ~CLl; 1·';1 eNGINe,RS, l __ ': 1.'5~) rl.'S "or CO'.D'oC'to AN INDEP:~O[~· ;,1'" ~'Af1~" NOR '0 "~\' AWAP, '~OO, ~HUW~ \!~ ~"VAI' ,w ~A" ""('eLY "(L'ce' 8~ THe ~8f)'" ~"ERENCcD TI _, R[,J~T ~'-J-'" ACCUIiAC, ~~) ';O~-'II' ~!;;o IC I:-IAI f).IINf _I K"'~ ~Ou~TY ,Af1r" ~CC _'.'7_'C~-'j_'~'-O& -')J'r~_n', 01 .ln~''', ~14~ fl • . 'UlI", ~ 2-' '1\ o":>!41)-IX'<.:,_~2, "",,,,,-, ~I)o' _0 BENCHMARK ell1 (,r Ef,~lO~ W~C''''~RK Nu~]P -,'A~',U "~''-> :. I'!"'" ~,i:1 , ": ~i: ~G"'E' CF THE C~~~oEr: "X,E G' TRAme "r,',,\L POLE ,'1-~( ~d: ~J'''E~ ")~,I! ',-i~l" A~I! Ic'~I'1 "":N~' ~t ELEVATC;N ~ ~~"',, 'EET --, C' R,~-8'J BE"Cr~I<~K ~U~&E" 2 l'J rCL~e \" 'l~~,>, !lI~K ~-Mlf'rn "~r l'~'H "'l~), ,l IN -~"'" ~, H)he ", ~~~.P 8~14 ("V~"QN = '8ri8-1 FEOl SURVEY INSTRUMENTATION r-9 , )g\' ,[' I" H-f CO',C~,-- . CU~J'""'~-'G~ ,,,,~ IHI., h~1 l-L,IIW 'r[ FOlLOW'NG i:CLlPME~T ~~[, P~O([C~~" ,,," f)T.\ .. ,-',TlON M"~"'Nm!G ""Nl'FftC"}RE"" ,H'I'I(ArC).,O ,,; fiE0l'Rm lY ',/g-\\;-\1-1'-<) ,'h'(JCl~lHl 'heU, ",Ll: "~"t""c .. ,'~ '-'..CU~'~' ~f'-',G ,J" [,(,[jI~G 'HE ~[oJUIR,M[~'; 8' ,',K \V-'I" ,~" BASIS OF BEARINGS ',O,WA,",,~ ~e '_"" ~[J1"2e'I""E 9(1",E[~ 'HE <I~G ,'?'!"H XO~'~I,I,\;T )' ~u3._:C ~'Gh~5 ,JI?-JEf cR~~C~ ~~~)p~'5a) HJ<IlD"IAl CO~.-ID M:J'II'W~I I'J~. W',. j~'U 'OJ"l-' I~ ",N;, A' -H, ~()\,'~ '"'~ ~~""< 8U"""'~ COfi~ER5 oJ' 3ECT")~ OZ, 'O':~~-,,~ 23N, R'f.G: ~F:. ~'.i VERTICAL DATUM ""c, O~ '" oc. _ ERE~,~EJ -; (P .)C ,E~TO~ -i,~ :-;)N"'~l ~t,~:;'i~:;"~ "::f~G ~[~',',:~, ,"'~~'~" <;r~N~'-"~~~"5 , ~',D 0, P"~ ~e" cAKe ~"'l',~ '~'~I':. A~:;'J'I"~" -"'F "lJ\' r"'["ECo. ,EC~~(,EC ~ ' .. :;_ ,V' rxC'C'1 fl' r~'i-lJ 'TI 0, SA,D WAC' '" [GN'ilnD -J '_''''; [,,-,,,",-' f'J' '-!~A~' "\"f.v",~, A,~ ~,,~"D::D ',h~:R P,~Q<DIN':; ~,_"H;:" ,g'l~, A\O ';;cfT-n,,' ,8"1,0'-• - -C~ ..,r'f' 5"-:"-1,~S"'h'"'C~ ~y )l,,' H,~'J"l'c[; '!"Wl~ ",-'.~KI""'~ "'}!,irEe 7,C" 'e"] ~"Rlf' f: ',,', • I, f,~"T" I AI r C' rOlf ~J"" ,,'--" 'J' mAC' 0" ,~"~:; r.o,~,-" ,'AS'''',GlCN 'M, -H,R ~ "-' '.".'l'i ~AJ" 0'--, ~', ",I.; "~EJ', R,C'lfiD,D ",'eel"" ' Jf P_,"". ,"~ )", [c1GfIH'"R "'T>-.... , -"S".F~I rc.:R \G",,,",, rC'F"~ .'M; .' n-;O~QSG':J%" ~." b:A~_"f-U bY ''-I''''l.Vl~ "'_~)Rrhl' LI'"ER R,;O,_,,':', '. J~of~ ~~~TG:;:' <AL' Cl TJI' NJ"IH ,''', J' '~A~' c, "'~ ",0 ,""[ :'~"C:N ,;>",.-,. "."!'<I"N'. IJ -"0 f-l" :rl"'~'. "t~'J,",t-D I" "'.lullE 0 U' ,-'_N', co~ '" KN:i CO,J~,lv. "A"'i~~,IC~: E'C,P' '~: E'-;I 40 f(Ef C' "r; If"[' ~Df,v vCD Ie KI"~ C)','~IY '0" HJA) 'l~"Q"" ~'['eel', "0'.:'<'0) '-',,'e' "'e.'.'~;". v.\la[~-, 'Q-/«, ,~) 71~'" :,1r:7 roc \, . ,-; "R," .. oW". -, ! -:,"//.'=";:/,,,5:;\'\,$'1 ..... ~\. L, ' "l'~.'v ci ,_,:;","'" Q!7 ~ ,,=>.'l ;1, i. ~.~ ',l..'-0}:.-o./";:;'':;';':'' ~c ,,~,,\) ~Iit §I* ·G z o zg J,Jo,,,, G!~ z, _ ~s ...J~i! o£, ~~~ 0°'3 (,)glL m {/) W ~ a I a: w z z a o E a " " -" E • • , , , " ; . ~ : ~ "'~ z § z I ~ w ~ «~ ..JQ >--a:~ W 8 I~ f-ti Zi5 « 0.. z ~ w ~ ~ o ~ u :~o )," ;;c ;'i PP,02 2 10, Figure 1.3 Proposed Site Conditions 1-4 ... j \ ' \ \ II i !l A PORTION OF THE SE 1/4 OF SECTION 32, TOWNSHIP 23N., RANGE 5E, KING COUNTY, WASHINGTON ~ ~ \ > '-'. ~\ l I TRACT (LANDSCAPE) w~ '. I·.· (fJH--~ 1 __ , j-W ~ '*~I >,. ~ 'M" '" "00' « Yi ".0'0. a, 25' ACCESS/UTIl +----\- \ ~~:~4!. .. \ __ r't'if _ ~_ \5hJ:\ , , \ I \ I \ I , , , , , '+---, ~-, EXISTING STRUCTURE \ TO BE RE~AIN ----...... ~~ I' ,,' ~li~i4i:'·iE~~"'-1".".~ _Jy,. '_ :-"<1" 't" .. : :: 1,---',N eg'54 " , ~ I t. 1 'i--, T , , , , '-L , ~ , , , , , , , , , , n SCALE: 1" _ 40' !""WIw-- <40' 2(1' 0 ",' eo' CONTOUR INTERVAL .. 2' LEGEND EXiSTING STORM DR.o!JNAGE EXISTING SANITARY SEWER EXISTING WATER ~N ---10 ~ PROPOSED 12"" STORM DRAINAGE ----.----e PROPOSED B"III SANITARY SEWER • * NOTES: PROPOSED B"" WATER MAIN FIRE HYDRANT STREET LIGHT PROPOSED LOT LINE BUILDING SETBACK UNE 1. SEE SHEET PP-07 FOR TYPiCAl STREET CROSS SECTIONS. ; ~ ,~ i '. 11 l! H • II E ji ~ }!! i 's; ,3';: '0 E • II • ~ ~ · ". :J H .' -" ~:g o. z "' " z ~ ~ w~ (fJ ~a. W «5 :2: -.Js 0 I a:::~ a: W~ w I~ z z 1-& 0 Z~ 0 «~ o..~ a. z 0 r z w ~ ~ 0 ~ " PP-05 5 10 Agure 1.4 Solis Map 1-5 M .£t .11 04<:1 M..(v.ll ,zzl t 0 c. w 0:: w 1:' ::J C. o CO ~p;; 00 0::'6 :gCl) j~~§~ (f) E .8 § '" ~ ::J U § .~ ~ 0 ~~ ~ ~ &; ., X ] a t 11 ~ .. ~ « • :;; ~~ I ~ ~ ~ ~ N g :;: .. " -I ~ §. ~ ~ £ 0 o£ z ........:::: M.9Zt oll1 M..9ZI .ZZt z Z h ~ ~ ~ ~ ~ Custom Soil Resource Report Map Unit Legend King County Area, Washington (WA633) Map UnH Symbol Map UnH Name AcreslnAOI Percant of AOI Age AldelWood gravelly sandy loam, 14.3 6 to 15 percent slopes --------------_. ---- AgD Alderwood gravelly sandy loam, 2.4 15 to 30 percent slopes ----------------------- Totals for Area of Interest 16.7 ------ Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps. can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas, A map unit is identified and named according to the taxonomic classification of the dominant soils, Within a taxonomic class there are precisely defined limits for the properties olthe soils, On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena, Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a Single taxonomic class rarely. if ever, can be mapped without including areas of other taxonomic classes, Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils, Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components, They mayor may not be mentioned in a particular map unit description, Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps, If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements, The delineation of such segments on the map provides sufficient information for the development of resource plans, If 10 85.5% 14.5% ---- 100.0% Custom Soil Resource Report King County Area, Washington AgC-Alderwood gravelly sandy loam, 6 to 15 percent slopes Map Unit Setting Elevation.' 50 to 800 feet Mean annual precipitation: 25 to 60 inches Mean annual air temperature: 48 to 52 degrees F Frost-free period: 180 to 220 days Map Unit Composition Alderwood and similar soils: 95 percent Minor components: 5 percent Description of Alderwood Setting Landform: Moraines, till plains Parent matefial: Basal till with some volcanic ash Properties and qualities Slope: 6 to 15 percent Depth to restfictive feature: 24 to 40 inches to densic material Drainage class: Moderately well drained Capacity of the most limiting layer to transmit water (Ksat): Very low to moderately low (0.00 to 0.06 in/hr) Depth to water table: About 18 to 37 inches Frequency of flooding: None Frequency of ponding: None Available water capacity: Very low (about 2.5 inches) Interpretive groups Farmland classification: Farmland of statewide importance Land capability (nonirrigated): 4s Hydrologic Soil Group: B Typical profile o to 12 inches: Gravelly ashy sandy loam 12 to 27 inches: Very gravelly sandy loam 27 to 60 inches: Very gravelly sandy loam Minor Components Norma Percent of map unit: 1 percent Landform: Depressions Bellingham Percent of map unit: 1 percent Landform: Depressions Seattle Percent of map unit: 1 percent Landform: Depressions Tukwila Percent of map unit: 1 percent 12 Custom Soil Resource Report Landform: Depressions Shalcar Percent of map unit: 1 percent Landform: Depressions AgD-Alderwood gravelly sandy loam, 15 to 30 percent slopes Map Unit Setting Elevation: 50 to 800 feet Mean annual precipitation: 25 to 60 inches Mean annual air temperature: 48 to 52 degrees F Frost-free period.' 180 to 220 days Map Unit Composition Alderwood and similar soils: 100 percent Description of Alderwood Setting Landform: Moraines, till plains Parent material: Basal till with some volcanic ash Properties and qualities Slope: 15 to 30 percent Depth to restrictive feature: 24 to 40 inches to densic material Drainage class: Moderately well drained Capacity of the most limiting layer to transmit water (Ksat): Very low to moderately low (0.00 to 0.06 in/hr) Depth to water table: About 18 to 37 inches Frequency of flooding: None Frequency of ponding: None Available water capacity: Very low (about 2.5 inches) Interpretive groups Farmland classification: Farmland of statewide importance Land capability (nonirrigated): 4e Hydrologic Soil Group: B Typical profile o to 12 inches: Gravelly ashy sandy loam 12 to 27 inches: Very gravelly sandy loam 27 to 60 inches: Very gravelly sandy loam 13 2. CONDITIONS AND REQUIREMENTS SUMMARY Review of the 8 Core Requirements and 6 Special Requirements This section describes how the project will meet the 2009 Surface Water Design Manual's Core and Special Requirements. Core Requirement No.1 Discharge at the Natural location In the existing conditions, the site drains to the west, towards Panther Creek A portion of the south parcel drains to an on-site wetland and flows oflsite to the west, however it drains into Panther Creek The proposed detention pond will discharge to the west comer of the site, which is the natural discharge location for the project site. Additionally, a portion of the northwest comer of the site will bypass the detention system and sheet flow into Panther Creek Core Requirement No.2 Off-site Analysis A Level 1 Downstream Analysis was performed by ESM on September 19, 2013. See Section 3 for the oflsite analysis. Core Requirement NO.3 Flow Control Based on the City of Renton's Flow Control Application Map, the project site is in the Row Control Duration Standard (Forested Conditions) area. See Section 4 for Row Control Analysis and Calculations. Core Requirement No.4 Conveyance System The stormwater drainage conveyance system will be sized to convey the 25 year design storm event and to contain the 100 year design storm event A detailed Conveyance System Analysis and Design will be provided with the final TIR. Core Requirement NO.5 Erosion and Sediment Control The proposed project will include clearing and grading for the 34 single-family units, associated roadways, and pond area. The 2 existing units and their associated driveways and accessory structures will be demolished. Erosion and sediment controls will be provided to prevent to the maximum extent possible, the transport of sediment from the project site to downstream drainage facilities, water resources, and adjacent properties. The Temporary Erosion and Sedimentation Control (TESC) Plans will be shown on the final construction plans and additional information will be provided with the final TlR. Core Requirement No.6 Maintenance and Operations The Operations and Maintenance Manual will be provided with the final TIR. Core Requirement No. 7 Financial Guarantees and Uabillty All drainage facilities constructed or modified for projects will comply with the financial guarantee requirements as provided in the City of Renton Bond Quantities Worksheet The Bond Quantities Worksheet, Facility Summaries, and Declaration of Covenant will be provided with the final TlR. Core Requirement NO.8 Water Quality The site does not meet the requirements for enhanced treatment in the 2009 Surface Water Design manual, therefore Basic Water Quality treatment will be provided. Treatment for the pollution generating surfaces will be provided by a stormfilter vault preceding the pond, and a stormfilter manhole for the bypass area. See Section 4 for more information. 2-1 Special Requirement No.1 Other Adopted Area-Specific Requirements There are no master drainage plans, basin plans, salmon conservation plans, stormwater compliance plans, fiood hazard reduction plan updates, or shared facility drainage plans for this project Special Requirement No.1 does not apply, Special Requirement No.2 Rood Hazard Area Delineation There is no 1 OO-year flood plain associated with a large body of water (i.e. lake or stream) on the site or adjacent to the site. Special Requirement No.2 does not apply. Special Requirement No.3 Rood Protection Facilities The project lies outside any pre-defined ftood plain. Special Requirement NO.3 does not apply. Special Requirement No.4 Source Control The project is a residential subdivision and is not subject to this requirement Special Requirement No.4 does not apply. Special Requirement NO.5 Oil Control The project does not have a "high-use site characteristic" and is not a redevelopment of a high-use site. Special Requirement NO.5 does not apply. Special Requirement No.6 Aquifer Protection Area According to the "Groundwater Protection Areas in the City of Renton" map, the project site is not in an Aquifer Protection Area. Special Requirement NO.6 does not apply. 2·2 3. OFF-51TE ANALYSIS Task 1: Study Area Definition and Maps Figure 1.2 shows the existing site conditions. Figure 3.2 shows the extent of offsite analysis and the downstream flow path from the site. Task 2: Resource Review • Row Control Map According to the City of Renton Row Control Application Map, the site is in a Row Control Duration Standard (Forested Conditions) area. • Soil Survey Map According to the Geotech Report prepared by Earth Solutions NW, the site is underlain primarily by native soils consisting of medium dense to very dense glacial till. Additionally, according to the USDA NRGS soil mapping service, the entire site is underlain by Alderwood Gravelly Sandy Loam (a till soil), which varies from 5-30%. See Rgure 1.4 for the Soils Map. • King Countv iMap According to the King County GIS Viewer (iMap), the project is NOT in any of the following areas: o Streams & 100 year floodplains o Seismic Hazard Areas o Coal Mine Hazard Areas o Wetlands Four wetlands were found and delineated on site, according to the Critical Area Report for Panther Lake, prepared by Sewall Wetland Consulting Inc. All four wetlands require a 25 foot standard buffer. In the southeast comer of the site there is a class 4 stream and an offsite wetland whose buffer is on site. Additionally, Panther Creek is a Class 2 stream that is off-site to the west of the project area that has a buffer that extends on site. o Landslide Hazard Areas According to the City of Renton regulations and criteria for Landslide Hazard Areas, the west portions of the site (over 40%) are classified as a landslide hazard area (although are not mapped as such in King County iMap). According to the Geotechnical Report by Earth Solutions NW, the slope is underlain by glacial till, therefore the overall global stability of the slope areas can be characterized as moderate. Slope stabilization, erosion control measures, and buffer zones will be utilized. 3-1 o Erosion Hazard Areas According to King County iMap, a portion of the north section of the project is located in an Erosion Hazard Area. According to the Geotechnical Report by Earth Solutions NW, the planned development will not increase the erosion hazard at the site, provided appropriate Best Management Practices are implemented during the earthwork and development activities. • Citv of Renton 2009 Surface Water Manual Amendments According to Reference 11 in the City of Renton 2009 Surface Water Design Manual Amendments, the project is NOT in any of the following areas: o Aquifer Protection Areas o Groundwater Protection Areas • Road Drainage Problems None noted • Wetlands Inventory Four wetlands were found and delineated on site, according to the Critical Area Report for Panther Lake, prepared by Sewall Wetland Consulting Inc. All four wetlands require a 25 foot standard buffer. In the southeast comer of the site there is a class 4 stream and an offsite wetland whose buffer is on site. Additionally, Panther Creek is a Class 2 stream that is off-site to the west of the project area that has a buffer that extends on site. Buffer averaging and mitigating is proposed for some of the wetlands, a wetland mitigation plan is provided under separate cover. • Migrating River Study None noted • Downstream Drainage Complaints There are no drainage complaints in the downstream flow path within the last 10 years. The project site will be releasing at the Row Control Duration Standards, Forested Site Conditions, and will not aggravate or impact any downstream flow paths. 3-2 Agure 3.1 KeGIS Parcel Report/Environmental Hazards 3·3 'g King County King County Districts and Development Conditions for parcel 3223059123 Parcel number Address 3223059123 1B655108TH AVE SE Drainage Basin Black River ~ -"." .-' .... ' ..... . Jurisdiction Zipcode Kroll Map page Renton 98055 604 Thomas Guide page 686 B Electoral Districts RNT 33-1204 -PlSS Latitude Longitude DlstrlCC1'~"~,._!!.~!, (206) 2 Congressional district 9 Legislative district .• School district i ..... Seattle school board district does not apply (not In Seattle) District Court electoral district Southeast ===-SW-32-23-5 47.43395 -122.19832 Fire district Water district Sewer district Water & Sewer district does not apply does not apply does not apply : _, ~ • 0- ~'·.,_1.·_· .. ' i :,' ;.'~ .". -',' . . "-',' "'.' . i' _., ""-.. , , ,-, . SOO& Creek Water & Sewer District Parks & Recreation district does not apply Hospital district Rural library district Tribal Lands? Public Hospital District No.1 Rural King County Library System No E1 King County planning "'an"'d!l •••• ®_,;ign?l~n~ __ _ Coal mine hazards? Erosion hazards? Landslide hazards? Seismic hazards? NA, check withjurisdiction None urn Urban does not apply So05 Creek None mapped V •• None mapped None mapped ==~ Forest Production district? Agricultural Production district? 1 OO·year flood plain? Wetlands at this parcel? This report was Contact us © does not apply 340 does not apply No No No None mapped None mapped None mapped PM g King County King County Districts and Development Conditions for parcel 3223059148 Parcel number 3223059148 Drainage Basin Address Not Available Jurisdiction Renton -Zipcode 98055 PLSS Kroll Map page 604 Latitude Thomas Guide page 686 Longitude B-ElectoralDislricts Congressional district Legislative district School district RNT 33-1204 9 • Black River SW·32·23·S 47.43492 -122.19779 Fire district Water district Sewer district Water & Sewer district ~ .. ·:'.·' ...... ·.i . "'. "' .. ,'," ',' ; . -. . , I: -. does not apply does not apply does not apply Soos Creek Water & Sewer District Parks & Recreation district does not apply Seattle school board district does not apply (not in Seattle) Hospital district Rural library district Tribal Lands? Pu~lic Hospital District No.1 Rural King County Library System No District Court electoral district Southeast R King County planning and designations Coal mine hazards? Erosion hazards? Landslide hazards? Seismic hazards? NA, check with jurisdiction None um Urna" does not apply Soos Creek None mapped None mapped None mapped None mapped Forest Production district? Agricultural Production district? 100-yearflood plain? Wetlands at this parcel? does not apply No does not apply 340 does not apply No No None mapped None mapped None mapped This report was geniie~,a~te~d~O~".'~2~14~l2iOI'1313I'iOj4:43 PM Contact us at ~ © 2010 King County ti King County King County Districts and Development Conditions for parcel 3223059273 Parcel number Address Jurisdiction Zipcode 3223059273 18647108TH AVE SE Drainage Basin Black River r" . Kroll Map page Renton 98055 604 Thomas Guide page 686 REiectoral Districts Congressional district Legislative district School district RNT 33·1204 -PLSS Latitude Longitude District 5, ~!!IJI.IIIII.' (206) 2.6·1005 IJ:d • • Seattle school board district does not apply (not in SeaUle) District Court electoral district Southeast Coal mine hazards? Erosion hazards? Landslide hazards? Seismic hazards? NA, check with jurisdiction None um Urban does not apply Soos Creek None mapped None mapped None mapped None mapped ===-SW-32-23-S 47.43492 -122.19804 Fire district Water district Sewer district Water & Sewer district does not apply does not apply does not apply i. ' " .. -. ' ....... . , . . cv··, .. '. . . ... '.. .... . . ',-,' ., -'-. , . 1'1 • Soos Creek Water & Sewer District Parks & Recreation district does not apply Hospital district Rural library district Tribal Lands? Public Hospital District No.1 Rural King County L.ibrary System No dOlls not apply 340 Forest Production district? Agricultural Production district? does not apply No No 1 DO-year flood plain? Wetlands at this parcel? This ",pon 'was No None mapped None mapped None mapped PM li King County King County Districts and Development Conditions for parcel 3223059344 Parcel number 3223059344 Drainage Basin Address Not Available Jurisdiction Renton -Zipcode 98055 PLSS Kroll Map page 60. Latitude Thomas Guide page 686 Longitude ·8 Electoral Districts RNT33-1204 ... 9 Black River SW-32-23-5 47.43491 -122.19864 Fire district Water district Sewer district Water & Sewer district does not apply does not apply does not apply SOO$ Creek Water & Sewer District Congressional district Legislative district School district • Parks & Recreation district does not apply Seattle school board district does not apply (not in Seattle) District Court electoral district Southeast Hospital district Rural library district Tribal Lands? Public Hospital Oistrict No.1 Rural King County Library System No ~.JSiI1fl.Q.o,,-nty planning and •••• l<designations---------- Coal mine hazards? Erosion hazards? Landslide hazards? Seismic hazards? NA, check with jurisdiction None um Urban does nol apply Soos Creek None mapped Yes None mapped None mapped Forest Production district? Agricultural Production district? 1 OO-year flood plain? Wetlands at this parcel? This report Contact ''';;~!!I!II! does not apply 3 •• does not apply No No No None mapped None mapped None mapped PM li King County King County Districts and Development Conditions for parcel 6623400050 Parcel number 6623400050 Drainage Basin Address 18819108TH AVE SE Jurisdiction Renton -Zipcode 98055 PLSS Kroll Map page 60. Latitude Thomas Guide page 686 Longitude El Electoral Districts RNT 33·1204 Distrlc"t~~.!!.II!!' (206)2 Congressional district Legislative district School district 9 • Seattle school board district does not apply (nol in Seattle) District Court electoral district Southeast Coal mine hazards? Erosion hazards? Landslide hazards? Seismic hazards? um Urban does not apply S005 Creek None mapped None mapped None mapped None mapped Black River ~ SW·32 ·23·5 47.43395 . ' . -122.19813 . . 'i' Fire district does not apply Water district dou not apply Sewer district does not apply Water & Sewer district Soos Creek Water & Sewer District Parks & Recreation district does not apply Hospital district Rural library district Tribal Lands? Public Hospttal District No, 1 Rural King County Library System No does not apply No does not apply 3.0 Forest Production district? Agricultural Production district? does not apply No No 100-yearflood plain? Wetlands at this parcel? This report we' gene, Contact None mapped None mapped None mapped ~ King County King County Districts and Development Conditions for parcel 6623400053 Parcel number Address Jurisdiction Zipcode 6623400053 18825108TH AVE SE Drainage Basin Black River r-........ . Kroll Map page Renton 98055 604 Thomas Guide page 686 ~_Ele<:;tgral Districts Congressional district Legislative district School district RNT 33-1204 -PLSS latitude longitude District 5, !I!I!I!I-IIIJ., (206)296-1005 IJiiJ 9 • 47.43348 ·122.19832 Fire district Water district Sewer district does not apply does not apply does not apply . . ,. ~' ......... ' ......... ' , .' .. ! I'. Water & Sewer district Soos Creek Water & Sewer District Parks & Recreation district does not apply Hospital district Seattle school board district does not apply (not in Seattle) Rural library district Public Hospital District No.1 Rural King County Library System No District Court electoral district Southeast Tribal Lands? -[3-_"!<-,,,i-!J9..g~unjy~l1Ilin~d •••• fCdlElesignatioflL ___________ _ Coal mine hazards? Erosion hazards? landslide hazards? Seismic hazards? NA, check with jurisdiction No .. urn Urban does not apply Soos Creek None mapped Ve. None mapped None mapped Forest Production district? Agricultural Production district? 1 DO-year flood plain? Wetlands at this parcel? does not apply 340 does not apply No No No None mapped None mapped None mapped PM l; King County King County Districts and Development Conditions for parcel 6623400054 Parcel number Address Jurisdiction Zipcode Kroll Map page Thomas Guide page 6623400054 Not Available Renton 98055 60. 686 Drainage Basin Black River PLSS Latitude Longitude ===-SW-32 ·23·5 47.43347 -122.19961 ="------------~---------------------------- Congressional district legislative district School district RNT 33·1204 District 5, I!I!!I-IIJ •• (206) 296-1005 t:iiJ 9 • Fire district Water district Sewer district Water & Sewer district does not apply does not apply does not apply Soos Creek Water & Sewer District Parks & Recreation district does not apply Hospital district Seattle school board district does not apply (not in Seattle) Rural library district Public Hospital District No.1 Rural King County Library System No District Court electoral district Southeast Tribal lands? 8. _Klngg9-"_riiy-plan,,ing ann.d:t ..•••• lI<dJEe;Ssignations Coal mine hazards? Erosion hazards? landslide hazards? Seismic hazards? NA, check with jurisdiction None um Urban does not apply Soos Creek None mapped Ves None mapped None mapped ==~ Forest Production district? Agricultural Production district? 100-year flood ptain? Wetlands at this parcel? This report was Contact does not apply 3.0 does not apply No No No None mapped None mapped None mapped PM Task 3: Field Inspection (Level 1 Inspection) A Level 1 Downstream Analysis was completed by ESM Consulting Engineers on September 19, 2013. The project is located in the Panther Creek Subbasin. The property directly to the north of the project site is fully developed, with a combined water quality/detention pond. No offsite runoff is anticipated to enter the project site from this development. At the south boundary of the site is Wetland D and a small stream, runoff from the south part of the project site enters here. No offsite runoff from the south is anticipated, as it will be intercepted by the small stream. 1 oath Ave SE is a fully developed roadway with curb and gutter, catch basins, and piped storm drainage. Although the road sits higher than the east portions of the site, all runoff from the road is captured by this storm system and conveyed elsewhere. There are three parcels and a portion of another that are in between the project boundary and 1 oath Ave SE. These parcels will drain onto the project These areas will be captured and routed to the proposed detention pond. This flow will not be detained, but will be treated for water quality. Task 4: Drainage Description and Problem DeSCriptions According to iMap, the entire project site is in the Black River (King County WRIA #9) basin. Black River is located to the northwest of the project site, and is tributary to the Duwamish Waterway. In general, the site flows from the east to the west The low point of the site is located roughly in the southwest portion of the site. The existing site sheet flows to the west and discharges to Panther Creek, or to the small stream at the south boundary of the project which is tributary to Panther Creek Panther Creek is approximately 40' vertically below the project site. Once in Panther Creek, the flows continue to the north in a well defined stream. Due to private property, fences, and elevation, Panther Creek was not able to be observed downstream. However, Panther Creek is a large, well defined channel, with no anticipated drainage problems. The proposed project will discharge to Panther Creek at a lower rate than currently existing. It will match the historic predeveloped flows (Flow Control Duration Standards, Forested Site Conditions), which are till forested conditions. The current site is about half lawn, 2 residences with associated outbuildings, and gravel driveways, therefore it is currently discharging more than historic predeveloped flows. Task 5: Mitigation of Existing or Potential Problems All runoff from the site will be collected in a piped storm system and directed to the proposed stormfilter vaUlt/detention pond. From there, runoff will be discharged at the Row Control Duration Standard (Forested Conditions) into Panther Creek, to the west. 3-4 Agure 3.2 Offsite Analysis Downstream Aowpath 3·5 ~' <* .... ;c;:_ II \ \ ) ','-, ... \ I SmHS; ~r ~"--:I , " \ ) J ~,-\ I I "''''1'l r' ~~ 'l>, ,- ..' C' .. \,} . dl :' ~"-r "."','s!) . \ j , . "'. '--I f ~-, .. -~ ........ ~~ (I) ( ,~';~ L r " r " ........ " '~, ,- j~ ( ) SEl85THR..- ~-';' t ,.. ~-, ~ 4 \. SE 'I8m+ ST i \ I :'--1 r - s' i ~ )-~.o l ') .~, \ , \ I , • ...., I r I r ~ ---, 'J -\ ~ .. ~, 'It \ ) '--;; ! ,-'" ·'tiII ' ·':t. " ~-.., , /¢' r' '--.'# -' " ._;-p ------. " " SE IITTH A.. l ~ , ~ ~ '\ S£I ~CT J ,* I, .. -I I _~"",1 ""(;'I: tC l lOOIl(;"liI Covnty "': R g ure 3.2 Offsi te An alysis Downst rea m R owp ath fit --=---q ~ g;:'S1TH1M l .~ --_ I,~ \ '~ \ " .(1.r:' ~. ~ .t '. , ~ \ \', ~ ~ ( , -'-. ~ I ~ € -, tJ ~..J , ~ -' I' ,~ -----' .. n-., ~ I \ ~ e \ ~ t ,,_ .... ---. ~ ~ ~ " ~ , ~c~ ,1' I " t I " "j \ 1 .......... .-' ,.J J-I. j '.ll - \'" , ~, \ ~ :d l-L. '-----, ~, '. j Lt ~ .~ ~ r---c.- i_, -, " , Sf. ~8nH LN " ,..' \.-. -.' SE1uu)CI~ -, '-:--=,' , '# ~ , , ) " , 5E l8!ITH ST l ~ ~, .r \ '-. ~ #--; '" I _ \ -" 1\- I -, I, r-', NJ ~ '\ 3 ( .... % 5" t' -, \, '- l.::.> , ..... , Photo 1. View of 1081h Ave SE from the south parcel entrance. 1081h Ave SE is a fully developed road with and existing storm system . Therefore , no runoff will be assumed to enter the property from 1 08 1h Ave SE. Photo 2. View of the southeast comer of the project. Photo 3. Southeast comer of the pro perty looking towards the existing house. There is a well defined , existing channel that exits the project site in the southwest corner and enters Panther Creek Photo 4. Continuation of the drainage channel to the west Photo 5. Continuation of the channel to the wes~ past the property boundary. Photo 6, View to the west from about th e middle of the south parcel. Th e si te slopes down towards Panthe r Creek I Photo 7. View to the west (west of photo 6) in the south parcel. Photo 8. View of the parcel to the north , which also slopes to the west. Photo 9. View from the same position, to the west. Both parcels slope to the west towards Panther Creek Photo 10. View from the west end of the south parcel, looking to the west The parcel ends with a steep slope down to Panther Creek ---====== Photo 11 . View to the west from the entrance of the north parcels. The site generally slopes from 1 oath Ave SE towards Panther Creek Photo 12, View of the west portion of the north parcels, looking to the south, The site slopes to the west (right side of the photo) towards Panther Creek. Photo 13. View to the north from the north parcels. The project site slopes to the west (left) towards Panther Creek The project to the north (Vista Hills , Vista Ridge) can be seen through the trees. These projects are fully built-out; therefore no oftsite nunon from the north will be modeled. Photo 14. View to the west from approximately the middle of the north parcels. The project site continues to slope to the west, towards Panther Creek. Photo 15, View from the west end of the north parcels, At the west end of the north parcels there is a steep slope which goes down to Panther Creek, This portion of the site is in an Erosion Hazard area, Photo 16. Existing stormwater pond in Vista Ridge (adjacent project to the north ). 4. FLOW CONmOL & WATER QUALITY FACILITY ANAL VSIS AND DESIGN 4.1 Existing Site Hydrology The existing site consists of 2 single-family dwellings with associated gravel driveways, along with a few detached structures. All structures on site will be demolished. The developable portion of the existing site is moderately sloped (slopes between 6-15%) and slopes down generally from the east side of the property towards the west At the west edge of the property, the site becomes very steep (15%+) and slopes down towards Panther Creek The pervious portions of the parcels around the buildings are generally lawn, while there is significant forested area on the west sides of most parcels. According to the Geotech Report prepared by Earth Solutions NW, the site is underlain primarily by native soils consisting of medium dense to very dense glacial till. Additionally, according to the USDA NRCS soil mapping service, the entire site is underlain by Alderwood Gravelly Sandy Loam (a till soil), which varies from 5-30%. Till soils are incapable of infiltration, therefore Till soils are used in the KCRTS model. To meet the City of Renton's Row Control Duration Standard (Forested Conditions), the entire predeveloped area is modeled as Till Forest. Approximately 1.45 acres of upstream area drains onto the site from the east, in between the project site and 1 08th Ave SE. See Table 4.3 TABLE 41 Pre-Develo pad Trlbutarv Area SUBBASIN TOTAL AREA nu,FOREST (Ac) (Ac) Panther Lake 8.04 8.04 TOTAL 8.04 8.04 4.2 Developed Site Hydrology The project will create 34 single family lots with associated roadway, sidewalk, driveways, roof areas, landscaped yards, and a combined detention/water quality pond. All 34 lots will have new single-family dwelling units. Building rooftops and impervious areas (driveway, porch) were estimated as 75% impervious, which is the maximum impervious area allowed by the City of Renton Zoning Code 4-2-11 OA for R-8 zoned lots. The detention pond is located in the south westem comer of the Site. The detained runoff will be discharged to the west to Panther Creek, a well defined stream. There are 3 parcels and a portion of a parcel that are between 108th Ave SE and the project site. These areas will be captured and routed to the proposed detention/water quality pond. These areas will not be detained, but will be treated for water quality. 4-\ TABLE 4.2 Developed Pond Detained Area SUBBASIN TOTAL IMPERV. AREA AREA(Ac) (Ae) Panther Lake 7.54 3.98 Offsite Area 1.45 0.34 TOTAL 8.99 4.32 TABLE 43 . Bypass Area SUBBASIN TOTAL IMPERV. AREA AREA(Ac) (Ac) Bypass Area 0.50 0.43 TOTAL 0.50 0.43 TILL GRASS (Ac) 3.56 1.11 4.67 TILL GRASS (Ac) 0.07 0.07 See Figure 4.1 for a visual representation of the Developed Tributary Area. 4.3 Perfonnanee Standards Performance Standards for flow control design use the KCRTS Methodology with hourly time steps as described in Section 4.4 below. Runoff files for the existing, and proposed conditions were created using the historic KCRTS time series data sets for the SeaTac Rainfall Region with a Correction Factor of 1.0. The site requires basic water quality treatment. Water quality will be satisfied with a stormfilter vault. which will be preceding the detention pond. Additionally, the bypass area in the northwest comer of the site will be treated with a stormfilter manhole. 4-2 4.4 Flow Control System The detention pond was sized per the requirements in the 2009 Suliace Water Design Manual. Per the City of Renton's Flow Control Application Map. the project site is in the Row Control Duration Standard (Forested Conditions) area. This standard requires the site to match the durations of high flows at their predevelopment levels for all flows from one- half of the 2 year peak flow up to the 50 year peak ftow. The offsite ftows being routed through the pond are not subject to ftow control, therefore the offsite ftows will be added to the predeveloped and developed flows. Predevcombined ~ predev (onsite) + offsite flows Devcombined ~ dey (onsite) + offsite flows The target flows are calculated as follows: 50% 2 year: 50% of the 2 year from predev (onsite) + offsite 2 year 50 year: predev 50 year + offsite 50 year The pond's inflow will be modeled using the devcombined time series and the pond's outflow will be the rdout time series. This rdout time series will match the Flow Control Duration Standard (Forested Conditions). KCRTS v6.0 was used to design the proposed pond. Procedures and design criteria specified in the 2009 Suliace Water Design Manual were followed for the hydrologic and hydraulic modeling. The KCRTS pond sizing output is included in Appendix A The KCRTS output models the required detention volume as 76,640 cubic feet of storage, with 8 feet of detention. The proposed pond provides 84,240 cubic feet of storage, which results in a construction/safety factor of 10%. 4-3 Agure 4.1 Pond Tributary Area 4-4 , , I , ~ , 1-i , e ~ 0 ., • e ~ w ..J " () "' ~."'O>""~.~ ,dO~<OUDl 1 ",,·,,'00_.00\ l"""d 1 ~~JOI/, o"cr'd "O'_OOld OoOl (U~<.,,~, O~'" t)~~J~~U~uUJ ""J ""."'''" lL,"'" WO::>"II",!:)wsa"MMM H",-,<" i«,> " ..... d]m. 1"1 .. 1.1 EQrnl6 .... M·~"MI ..... I>"~, mm:I goz: ..... ·8 's ""'''' 419 QflI"Cr: ~ '" S!j33NI~N3 ~NlllnSNO:) " .~ 0 2 ~ <t LoJ CL <f NOIONIHSIIM .lVld ~-'-'C--'- I I \ --IT D Z .~ n \ \ \ \ I ______________ ------------1 IflllV AllV In 8111l ONOd ~·t 311n~[,I NOlN3!:j ; 1 ; 11 ,1 ! c " . , ~ .. I I Al:IVNIV\J1l3l:1d l:I3H.lNVd ~ .,: ,~ 0 S3V'JOH « W CL <t 1:I3NNOQ ozo UCZ iJlf=O OZL CLc.; Of- Q:W 0.-(-=:J I I 1 C, , ! ,·i 0 ii . 0 '~ I u::: J ~I~ ~ flr_ ,e"I1-"'" ''''I: ~8 P.IO"," ~d t. t '1:1/9~!l . ..,,,Old ~.HO_NJ\"'''"'.\rl O·."O\9<;W.SIlC·-"~l\,i"".~w"l\ , '"':, 4.5 Water Quality Facility The proposed stormfilters for Panther Lake have been sized by Contech. The stormfilter vault will be sized using the KCRTS devcombined inflow (which is the inflow to the pond). The stormfilter manhole will be sized using the bypass KCRTS peak file. The Contech sizing sheets are included in Appendix D. 4-5 5. CONVEYANCE SYSTEM ANALYSIS AND DESIGN The stormwater drainage conveyance system will be sized to convey the 25 year design storm event and to contain the 100 year design storm event A detailed Conveyance System Analysis and Design will be provided with the final TIR. 5·) 6. SPECIAL REPORTS AND STUDIES Following are the reports and studies referenced for the proposed development: • Geotechnical Engineering Report, by Earth Solutions NW, LLC, dated September 23, 2013. (Appendix B) • Critical Area Report for Panther Lake, by Sewall Wetland Consulting Inc, dated January 28, 2014. (Appendix C) 6-1 7. OTHER PERMITS The National Pollutant Discharge Elimination System (NPDES) permit will be prepared with the final construction plans. This project also requires the following permits: Building Permits Clearing & Grading Permits 7-1 8. CSWPPP ANALYSIS AND DESIGN cswppp analysis and design will be provided with final engineering. 8-1 9. BOND QUANTITIES, FACILITY SUMMARIES, AND DECLARATION OF COVENANT The Bond Quantities, Facility Summaries, and Declaration of Covenant will be provided with the fi nal TI R. 9-1 10. OPERATIONS AND MAINTENANCE MANUAL The Operations and Maintenance Manual will be provided with the final TIR. 10-1 APPENDIX A KCRTS Pond Sizing Output Panther Lake Vault KCRTS Output Pre-Developed Land Use Condition 7.98 0.00 0.00 0.00 0.00 0.00 0.00 0.00 pr'edev. tsf 0.00 0.00 0.08 0.00 0.00 0.00 0.00 0.00 0.000080 Till Forest 0.000000 Till Pasture 0.000000 Till Grass 0.000000 Outwash i"orest 0.000000 Outwas~ Pasture 0.000000 Cutwas~ Grass 0.000000 Wetland 0.000000 Impervious ST 1.000000 flow Frequency Analysis Time Series File:predev.tsf Project Location:Sea-Tac ---Ann'.lal Flow Rate (CFS) 0.236 0.461 0.507 0.159 0.122 0.179 0.315 0.268 0.209 0.222 0.182 0.339 0.184 0.110 0.14 7 0.182 0.128 0.140 0.312 0.185 0.180 0.153 0.124 0.377 0.167 0.181 0.271 0.167 0.019 0.145 0.087 0.234 0.129 0.234 0.227 0.151 0.073 0.390 0.315 0.119 0.076 Peak Flow Rates--- Rank Time of Peak 16 5 2 32 42 28 9 13 21 20 24 8 23 44 36 25 40 38 11 22 27 34 41 7 30 2/16/49 3/03/50 2/09/51 1130/52 1/18/53 1/06/54 2107/55 12120/55 12/09/56 1/16/58 1/24/59 11/20/59 2124/61 1/03/62 11/25/62 1/01/64 11/30/64 1/06/66 1/19/67 2/03/68 12/03/68 1113170 12/06/70 2/28/72 1113/73 22:00 16:00 18:00 9:00 19:00 5:00 21:00 17:00 15:00 20:00 2:00 21:00 15:00 2:00 15:00 18:00 12:00 3:00 14:00 23:00 17: 00 23:00 8:00 3:00 5:00 26 1/15/74 2:00 12 12/26/74 23:00 29 12/03/75 17,00 50 3/24/77 20:00 37 12/10/77 17:00 46 2/12/79 8:00 18 12/15/79 8:00 39 12/26/80 4:00 17 10/06/81 15,00 19 1/05/83 8:00 35 1/24/84 11:00 48 2/11/85 6:00 6 1/18/86 21:00 10 11/24/86 4:00 43 1/14/88 12:00 47 4/05/89 16:00 LogPearsoTl III Coefficients Mean= -0.715 StdDev= 0.233 Skew= -0.140 -----Flow Frequency Analysis------- - -Peaks Rank Return Prob (CFS) Pe~iod 0.537 1 89.50 0.989 0.507 0.481 0.470 0.461 0.390 0.377 0.339 0.315 0.315 0.312 0.271 0.268 0.262 0.244 0.236 0.234 0.234 0.227 0.222 0.209 0.185 0.184 0.182 0.182 0.181 0.180 0.179 0.167 0.167 0.163 0.159 0.156 0.153 0.151 0.147 0.145 0.140 0.129 0.128 0.124 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 32.13 19.58 14.08 10.99 9.01 7.64 6.63 5.86 5.24 4.75 4 . 34 3,99 3.70 3.44 3.22 3.03 2.85 2,70 2.56 2.44 2.32 2.22 2.13 2.04 1. 96 1. 89 1. 82 1. 75 1. 70 1. 64 1. 59 1. 54 I .49 1. 45 1. 41 1. 37 1. 33 1. 30 1.27 1. 24 0.969 0.949 0.929 0.909 0.889 0.869 0.849 0.829 0.809 0.789 0.769 0.749 0.729 0.709 0.690 0.670 0.650 0.630 0.610 0.590 0.570 0.550 0.530 0.510 0.490 0.470 0.450 0.430 0.410 0.390 0.370 0.350 0.330 0.310 0.291 0.271 0.251 0.231 0.211 0.191 0.537 1 1/0 /90 :00 0.122 42 1.21 0.1 '/ 1 0.470 4 4/0 /91 :00 0.L9 43 1.18 0.le1 0.106 33 112 192 1 :00 0.110 44 1. 1.') 0.131 0.163 31 3/23/93 0:00 0.092 45, 1.12 0.111 0.045 49 3/03/94 3:00 0.087 46 1.10 0.091 0.244 15 2/19/95 ?0:00 0.076 47 1. 08 0.071 0.481 3 2/09/96 1:00 0.073 48 1. 05 0.051 0.262 14 1102/97 9:CO 0.045 49 1. 03 0.031 0.092 45 1/07/98 11: CO 0.019 50 1. 01 0.011 Compl:ted Peaks 0.635 100.00 0.990 Comp1.:ted Peaks 0.557 50.00 0.980 Computed Peaks 0.480 25.00 0.960 Computed Peaks 0.380 10.00 0.900 Computed Peaks 0.359 8.00 0.875 Computed Peaks 0.304 5.00 0.800 Compl:ted Peaks 0.195 2.00 0.500 Computed Peaks 0.129 1. 30 0.231 Developed Land Use Condition 0.00 0.00 0.000000 Till Forest 0.00 0.00 0.000000 Till Pasture 3.64 0.00 0.000000 Till Grass 0.00 0.00 0.000000 Outwash Fo:::::est 0.00 0.00 0.000000 Outwash Pasture 0.00 0.00 0.000000 Outwash Grass 0.00 0.00 0.000000 Wetland 4.34 0.00 C.OOOOOO Impervious dev.tsf ST 1.000000 Flow Frequency Analysis 1ogPearson III Coefficients Time Series File:dev.tsf Mean:=: 0.125 StdDev= 0.114 Project Location:Sea-Tac Skew= 0.399 ---l'._nnual Peak Flow Rates--------Flow Frequency Analysis------- Flow Rate Rank Time of Peak --Peaks Rar_k Return Prob ICFS) ICFS) Period 1. 38 21 2/16/49 21:00 2.51 89.50 0.989 2.39 2 3/03/50 16: 00 2_39 2 32.13 0.969 1. 43 19 2/09/51 2:00 2.27 3 19.58 0.949 1. 06 40 10/15/51 13: 00 2.19 4 14.08 0.929 1. 04 45 3/24/53 15:00 1. 89 5 10.99 0.909 1. 27 26 12/19/53 19:00 1. 8 6 6 9.01 0.889 1. 31 23 11/25/54 2:00 1.77 7 7.64 0.869 1. 28 25 11/18/55 15:00 1. 76 8 6.63 0.849 :.54 14 12/09/56 14: 00 1. 66 9 5.86 0.829 1. 34 22 12/25/57 16:00 1. 63 10 5.24 0.809 0.989 47 11/18/58 13:00 1. 61 1l 4.75 0.789 1. 30 24 11120/59 5:00 1. 58 12 4.34 0.769 1.15 36 2/14/61 21:00 1. 57 13 3.99 0.749 1.12 38 11/22161 2:00 1. 54 14 3.70 0.729 1. 15 35 12/15/62 2:00 1. 53 15 3.44 0.709 1. 27 27 12/31/63 23:00 1. 51 16 3.22 0.690 1. 14 37 12/21/64 4:00 1. 5] 17 3.03 0.670 1. 15 34 1/05/66 16:00 1. 47 18 2.85 0.650 1. 76 8 11/13/66 19:00 1. 43 19 2.70 0.630 1. 89 5 8/24/68 16: 00 1. 42 20 2.56 0.610 1. 05 41 12/03/68 16: 00 1. 38 21 2.44 0.590 1.16 33 1/13/70 22:00 1. 34 22 2.32 0.570 1.12 39 12/06/70 8:00 1. 31 23 2.22 0.550 1. 77 7 2/27/72 7:00 1. 30 24 2.13 0.530 1. ,:,2 "1 .)5 1. 6E 1. 05 1.19 1. 63 1. 42 1. 51 1. 57 2.19 1. 53 1. 24 1. 04 1. 5J 1. 86 0.802 1. 04 2.51 2.27 1. 20 0.755 0.884 1. 19 1. 61 1. 47 1. 58 4 C. 28 9 42 3~ 10 20 17 13 4 15 29 43 16 6 49 44 1 3 30 50 48 32 11 18 12 1/L~/F3 2:00 11/28/73 9:00 12/26/7·1 ::::'3: CO 12/02/'/.) 8/26/77 9/17/78 9/08/79 12/~4/79 11/21/80 JO/06/81 10/28/82 1/03184 6/06/85 1/18/86 10126/86 11111/87 8/21/89 1/09/90 11/24/90 1127/92 11/01/92 11 130/93 11/30/94 2/08/96 1/02/97 10104/97 2J:CO 2:GO 2,00 15:JO 21: 00 11,00 0,00 16,00 1: 00 22:00 16:00 0:00 0:00 17:00 6:00 8,00 1::::00 16:00 22:00 4:00 10:00 6,00 15,00 Computed Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks Developed 15 min Peaks Flow Frequency Analysis Time Series File:dev15.tsf Project Location:Sea-Tac ---Annual Flow Rate (CFS) 3.53 4.77 2.03 2.40 1. 73 1. 99 1. 67 2.50 2.43 2.24 2.83 2.88 2.43 2.00 1. 97 1. 53 2.28 1. 53 Peak Flow Rates--- Rank Time of Peak 9 2/16/49 17,45 5 3/03/50 15,00 35 8/27/51 18,00 27 10/17/51 7:15 43 9/30/53 3,00 38 12/19/53 17,30 46 7/30155 21,15 20 10/04/55 10,00 24 12/09/56 12,45 32 1/16/58 10:00 14 10/18/58 19:45 13 10/10/59 22,00 26 2/14/61 20,15 37 8/04/62 13:15 39 12/01/62 20:15 48 6/05164 15:00 30 4/20/65 19:30 49 1/05/66 15:00 1.78 1. 27 ___ .27 1. 25 1. 24 1. 20 1.19 1.19 1.16 1.15 1.15 1.15 1.14 1.12 1.12 1. 06 1. 05 1. 05 1. 04 1. 04 1. 04 1. 02 0.989 0.884 0.802 0.755 2.66 2.42 2.19 1. 89 1. 83 1. 65 1. 31 1. 09 23 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 2.04 1. 96 1. 89 1. 82 1. 75 1. 70 1. 64 1. 59 1. ~4 1. 49 1. 45 1. 41 1. 37 1. 33 1. 30 1. 27 1. 24 1. 21 1. 18 1. 15 1.12 1.10 1. 08 1. 05 1. 03 1. 01 100.00 50.00 25.00 10.00 8.00 5.00 2.00 1. 30 0.5 ___ 0 O. ·191) 0.470 0.450 0.430 0.410 0.390 0.370 0.350 0.330 0.310 0.291 0.27 J C.2S1 0.231 0.211 0.191 0.171 0.151 0.131 0.11] 0.091 0.071 0.051 0.031 0.011 0.990 0.980 0.960 0.900 0.875 0.800 0.500 0.231 1ogPearson III Coefficients Mean= 0.402 StdDev= 0.166 Skew= 1.390 -----Flow Frequency Analysis------- --Peaks Rank Return Prob (CFS) Period 10.14 1 89.50 0.989 6.07 2 32.13 0.969 5.39 3 19.58 0.949 4.92 4.77 4.00 3.65 3.58 3.53 2.97 2.92 2.90 2.88 2.83 2.70 2.64 2.64 2.59 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 14.08 10.99 9.01 7.64 6.63 5.86 5.24 4.75 4.34 3.99 3.70 3.44 3.22 3.03 2.85 0.929 0.909 0.889 0.869 0.849 0.829 0.809 0.789 0.769 0.749 0.729 0.709 0.690 0.670 0.650 2.64 17 5.39 3 2.35 29 1. 41 50 1. 70 45 3.65 7 2.01 36 2.46 22 2.59 18 1. 80 42 1. 63 47 2.92 11 4.00 6 2.90 12 2.70 15 6.07 2 2.44 23 1. 88 40 1.73 44 2.58 J9 2.97 10 2.38 28 2.21 33 3.58 8 2.43 25 1.86 41 2.27 31 2. 11 34 2.50 21 2.64 16 10.14 1 4.92 4 Computed Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks 11/ 3/66 17:15 81 4/63 15:00 lu/ 0/68 12:00 1/13/70 20:45 12/:)6/70 12/08/71 4118/73 11/28/73 8/17/75 10/29/75 8/23/77 9117/78 9/08/79 12/14/79 9/21/81 10/05/81 10/28/82 1102184 6/06/85 10/27/85 10/25/86 5113/88 8/21/89 1/09/90 4/03191 1/27/92 6/09/93 11117/93 6/05/95 5/19/96 12/29/96 10/04/97 7:0C 17: 15 9:30 8:00 23:00 7:00 14:30 1:00 13:45 20:00 8:00 22: J 5 16:00 23:45 21:15 10:45 22:45 17: 30 16:00 5:30 20:15 15:00 12:15 16: 45 17:00 1 : 30 1 : 45 1 : 15 /..58 2.5C 2.50 2.16 2.44 2.43 2.43 2.43 2.40 2.38 2.35 2.28 2.27 2.24 2.21 2.11 2.03 2.01 2.00 1. 99 1. 97 1. 88 1. 86 1. 80 1. 73 1. 73 1. 70 1. 67 1. 63 1. 53 1. 53 1. 41 8.78 7.08 5.69 4.21 3.96 3.31 2.32 1. 88 :9 20 21 77 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 5C 2.7n 2.56 2.44 2.3) 2.22 2.13 2.04 1.96 1. 89 1. 82 1. 75 1. 70 1. 64 1. 59 1. 54 1. 49 1. 45 1. 41 1. 37 1. 33 1. .30 1. 27 1. 24 1. 21 1.18 1.15 1.12 1. 10 1. 08 1. 05 1. 03 1. 01 100.00 50.00 25.00 10.00 8.00 5.00 2.00 1. 30 0.63:) 0.61J 0.59::' n.57:] o . ~j~) 0.530 0.510 0.490 0.470 0.450 0.430 0.410 0.390 0.370 0.350 0.330 0.3:0 0.291 0.271 0.251 0.231 0.211 0.191 0.171 0.151 0.131 0.111 0.091 0.071 0.051 0.031 0.011 0.990 0.980 0.960 0.900 0.875 0.800 0.500 0.231 Offslte Land Use Condition 0.00 0.00 1.16 0.00 0.00 0.00 0.00 0.34 offsite.tsf ST 1.000000 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000000 Till Forest 0.000000 Till Pasture 0.000000 Till Grass 0.000000 Outwash Forest o.ooooeo Outwash Pasture C.OOOOOO Outwash Grass 0.000000 Wetland c.ooooeo Impervious Flow Frequency Analysis Time Series File:offsite.tsf Project Location:Sea-Tac LogPearson III Coefficients Mean~ -0.796 StdDev~ 0.149 Skew~ 0.459 ---Annual Peak Flow Rates--- Flow Rate Rank (CFS) 0.172 19 0.373 1 Time of Peak 2116/49 21:00 3/03/50 16:00 -----F1ow Frequency Analysis------- - -Peaks Rank Return Prob (CFS) Period 0.373 1 89.5C 0.989 0.369 2 32.13 0.969 0.198 12 0.120 41 0.117 42 0.155 26 0.162 21 C.168 20 0.198 11 0.158 25 0.116 44 0.162 23 0.140 31 0.123 40 0.145 29 0.150 28 0.130 37 0.137 34 0.212 8 0.211 9 0.127 38 0.140 32 0.140 33 0.252 5 0.117 43 O.lEl 24 0.225 7 0.130 36 0.115 45 0.186 17 0.126 39 0.194 15 0.183 18 0.289 4 0.162 22 0.]54 27 0.106 46 0.207 10 0.189 16 0.087 48 0.100 47 0.369 2 0.322 3 0.143 30 0.085 49 0.083 50 0.131 35 0.232 6 0.194 14 0.196 13 Computed Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks 7/0S!/5J ):C0 1/30/:<2 S: C·O 3/24/53 15:00 L?/19/53 19::)0 2/07/55 17:JO 12/20/55 17:00 12/09/56 14:00 12/25/57 16:00 1/26/59 20:00 11/20/59 5:00 2/14/61 21:00 11/22/61 2:00 12/15/62 2: 00 12/31/63 23: 00 12/21/64 4:00 1/05/66 16:00 11/13/66 19:00 8/24/68 16:00 12/03/68 16:00 1/13/70 22:00 12/06/70 8: 00 2/27/72 7:00 l!l3/73 2:00 11/28/73 9: 00 12/26/74 23:00 12/02/75 20: 00 8/26/77 2:00 9/22/78 19:00 9/88/79 15: 00 12/14/79 21: 00 11/21/80 11:00 10/06/81 15:00 10/28/82 16:00 3/15/84 20: OC 6/06/85 22:00 1/18/86 16: 00 10/26/86 0:00 1/14/88 12:00 11/05/88 14: 00 1/09/90 6:00 11/24/90 8:00 1/27/92 15:00 3/22/93 22:00 11/30/93 22:00 11/30/94 4: 00 2/08/96 10: 00 1/02/97 6:00 10/04/97 15:00 0.:i2:2 0.289 0.252 0.232 O.22j 0.212 0.211 0.207 0.198 0.198 0.196 0.194 0.194 0.189 0.186 0.183 0.172 0.168 0.162 0.162 0.162 O. 16, 0.158 0.155 0.154 0.150 O. 145 0.143 0.140 0.140 0.140 0.137 O. 131 0.130 0.130 0.127 0.126 0.123 0.120 0.117 0.117 O. 116 0.115 0.106 0.100 0.087 0.085 0.083 0.397 0.350 0.306 0.251 0.240 0.211 0.156 0.123 3 4 5 6 8 9 10 11 12 13 14 l5 :6 :7 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 ~9.58 :4.08 10.99 9.01 '/ . 64 6.63 5.86 5.24 4.75 4.34: 3.99 3.70 3.44 3.22 3.03 2.85 2.70 2.S6 2.44 2.32 2.22 2.13 2.04 1. 96 1. 89 1. 82 1. 75 1. 70 1. 64 1. 59 1. 54 1. 49 1. 45 1. 41 1. 37 1. 33 1. 30 1. 27 1. 24 1. 21 1. 18 1. ] 5 1. 12 1. 10 1. 08 1. 05 1. 03 1. 01 100.00 50.00 25.00 1C.OO 8.00 5.00 2.00 1. 30 0.949 0.929 0.909 0.889 0.869 0.849 0.829 0.809 0.789 0.769 0.749 0.729 C.709 0.690 0.670 0.650 0.630 0.61C 0.59C 0.57C O.SSC 0.53C 0.510 0.49C O.47C O.4SC 0.43C 0.410 O.39C 0.370 0.35C O.33C 0.310 0.291 0.271 0.251 0.231 0.211 0.191 0.171 0.151 0.131 0.111 0.091 0.071 0.051 0.031 0.011 0.990 0.980 0.960 0.900 0.875 0.800 0.500 0.231 As stated In the TIR, the predeveloped and developed flows have been combined with the offsite flow (which is flow-through, no detention requirements). Predevcomblned Aow Frequency Analysis predev.tsf + offsite,tsf -predevcombined,tsf Flow Frequency Ana:ysis Time Series File:predevcombined,tsf Project Location:Sea-Tac logPearso~ III Coefficients Mean= -0.502 StdDev= 0.213 Skew= -0.055 ---Annual Peak Flow Rates--------Flcw Frequency Analysis------- Flow Rate Rank Time of Peak (CFS) 0,390 0.835 0.657 0,271 0,198 0,286 0,438 0,436 0,397 0.319 0.258 0,497 0.272 0.179 0.274 0,294 0.212 0.271 0.495 0,297 0.292 0,284 0.264 0,601 0.257 0.282 0.496 0.296 0.117 0.269 0.141 0.329 0.262 0.523 0.345 0.276 0.143 0.564 0.490 0.206 0.127 0,845 0.726 0.283 0.238 0,102 0,339 0.680 17 2 5 33 44 26 14 15 16 21 38 9 32 45 2/16/49 3/03/50 2/09/51 1/30152 1118/53 12119/53 2/07/55 12/20155 12109/56 1116/58 1/24/59 11/20/59 2/14161 1/02/62 16:00 18:00 8:00 19:00 19:00 19:00 17:00 14:00 17:00 1:00 21: 00 21 : 00 22:00 31 12/15/62 2:00 24 12/31/63 23:00 41 11/30/64 7:00 34 1/05166 16:00 11 1/19/67 14:00 22 2/03/68 22:00 25 12/03/68 17:00 27 1/13170 23:00 36 12/06/70 8:JO 6 2/28172 3:00 39 1/13/73 4:00 29 1/15/74 2:00 10 12/26/74 23:00 23 12/02/75 20:00 49 8/26177 2:00 35 12/10/77 17:00 47 11/19/78 3:00 20 12/14/79 21:00 37 12/26/80 0:00 8 10/06/81 15:00 18 1/05183 8:00 30 1/03/84 1:00 46 2/11/85 3:00 7 1/18/86 16:00 12 11/24/86 4:00 42 1/14188 12:00 48 12/30/88 5:00 1 1/09190 6:00 3 11/24/90 8:00 28 1/27/92 17:00 40 3/22/93 23:00 50 2/17/94 18:00 19 2/19/95 18:00 4 2/08/96 10:00 - -Peaks Rank Return Prob (CFS) Period 0.845 1 89.50 0,989 0.835 0.726 0.680 0.657 0.601 0.564 0.523 0.497 0.496 0.495 0.490 0.440 0.438 0.436 0.397 0.390 0.345 0.339 0.329 0.319 0.297 0.296 0,294 0,292 0,286 0.284 0,283 0.282 0,276 0,274 0.272 0.271 0,271 0,269 0,264 0.262 0.258 0.257 0,238 0.212 0,206 0,205 0,198 0.179 0.143 0. 141 0.127 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 '8 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 32.13 19.58 14.08 10.99 9.01 7.64 6.63 5.86 5.24 4.75 4.34 3.99 3.70 3.44 3.22 3.03 2.85 2.70 2.56 2.44 2,32 2.22 2.13 2,04 1. 96 1. 89 1. 82 1. 75 1. 70 1. 64 1. 59 1. 54 1. 49 1. 45 1. 41 1. 37 1. 33 1. 30 1. 27 1. 24 1. 21 1. 18 1.15 1.12 1.10 1. 08 1. 05 0,969 0.949 0,929 0,909 0.889 a.8E9 0,849 0.829 0.809 0,789 0.769 0,749 0.72.9 0.709 0,690 0.670 0,650 0,630 0.610 0.590 0.570 0.550 0.530 0.510 0.490 0.470 0.450 0.430 0.410 0.390 0.370 0.350 0.330 0.310 0.291 0.271 0.251 0.231 0.211 0.191 0.171 0,151 0.131 0.111 0.091 0.071 0.051 0.440 13 0.:::0.5 43 Conputed Peaks C:)mp'J.ted Peaks ComV.lted Peak.s ComFJted Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks 1/0:'::/97 10/30/9"1 c:OC 7:0C O. ]] 7 0.102 0.968 0.8.52 0.738 0.590 0.559 0.477 0.316 0.218 49 ~.03 50 ;.01 10C.00 5G.00 25,.00 1 C. 00 8.00 5.00 2.00 1. 30 D.::nl Q,99U 0,980 0.960 0.900 0.875 0.800 0.500 0.231 Devcomblned Flow Frequency Analysis dev.tst + offsite.tst = devcombined.tst ~low Frequency Analysis Time Series File:devcornbined.tsf Project Location:Sea-Tac ---Annual Peak Flow Rates--- F]ow Rate Rank Time of Peak (CFS) 1. 55 2.76 1. 63 1.17 1.15 1. 43 1. 4 6 1. 43 1. 74 1. 50 1.10 1. 46 1. 29 1. 24 1. 30 1. 42 1.27 1. 29 1. 97 2.10 1. 18 1. 31 1. 25 2.03 1.14 1. 41 1. 88 1.19 1. 31 1. 82 1. 55 1. 70 1. 75 2.46 1.69 1. 39 1. 15 1.72 2.04 0.886 1.12 20 2 19 42 43 25 23 26 14 22 47 24 35 39 34 27 37 36 8 5 41 32 38 7 45 28 9 40 33 11 21 16 13 4 17 29 44 15 6 49 46 2/16/49 3/03/50 2109/51 10/15/51 3/24/53 12/19/53 11/25/54 11 /1S / 55 12/09/56 12125/57 11/18/58 11/20/59 2/14/61 11/22/61 12/15/62 12/31/63 12/21/64 1/05/66 11/13/66 8/24/68 12/03/68 1/13/70 12/06/70 2/27/72 l/J 3/73 11/28/73 12/26/74 12102175 8/26/77 9/22/78 9/08/79 12/14/79 11/21/80 10/06/S1 10/28/82 1/03/84 6/06/85 1/18/86 10/26/86 1/14/88 8/21/89 21:00 16:00 2:00 13:00 15:00 19:00 2:00 15:00 14:00 16: 00 13:00 5:00 21:00 2:00 2:00 23:00 4: 00 16:00 19:00 16:00 16:00 22:00 8:00 7:00 2:00 9:00 23:00 20:00 2:00 19:00 15:00 21:00 11: 00 0:00 16:00 1:00 22:00 16:00 0: 80 0:00 17:00 LogPearson III Coefficients Mean= 0.174 StdDev= 0.118 Skew= 0.396 -----Flow Frequency Analysis------- - -Peaks Rank Return Prob (CFS) Period 2.87 1 89.50 2.76 2 32.13 2.59 3 19.58 2.46 2.10 2.04 2.03 1. 97 1. 88 1. S4 1. 82 1. 77 1. 75 1. 74 1.72 1. 70 1. 69 1. 66 1. 63 1. 55 1. 55 1. 50 1. 46 1. 46 1. 43 1. 43 J .42 1. 41 1. 39 1. 35 1. 32 1. 31 1. 31 1. 30 1. 29 1. 29 1. 27 1. 25 1. 24 1. 19 1. 18 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 2; 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 14.08 10.99 9.01 7.64 6.63 5.86 5.24 4.75 4.34 3.99 3.70 3.44 3.22 3.03 2.85 2.70 2.56 2.44 2.32 2.22 2.13 2.04 1. 96 1. 89 1. 82 1. 75 1. 70 1. E4 1. 59 1. 54 1. 49 1. 45 1. 41 1. 37 1. 33 1. 30 1. 27 1. 24 0.989 0.969 0.949 0.929 0.909 0.889 0.869 0.849 0.829 0.809 0.789 0.769 0.749 0.729 0.709 0.690 0.670 0.650 0.630 0.610 0.590 0.570 0.550 0.530 0.510 0.490 0.470 0.450 0.430 0.410 0.390 0.370 0.350 0.330 0.310 0.291 0.271 0.251 0.231 0.211 0.191 2.87 1 1/09/90 C: OJ 1.17 2.59 3 11124/90 8: OJ 1.15 1. 35 30 1/27/92 15:00 1.15 0.828 50 17/]0/9) E: O:J 1. I t, 0.966 48 11130/93 L2:0~ 1.12 1. 32 31 11130/94 4: 00 1.10 1. 84 10 2/08/96 10: 00 C.966 1. 66 18 1/02/97 6: 00 0.886 1.77 12 10/04/97 15:00 0.828 Computed Peaks 3.04 Computed Peaks 2.76 Cbmputed Peaks 2.49 Computed Peaks 2.13 Computed Peaks 2.06 Computed Peaks 1. 86 Computed Peaks 1. 4 7 Computed Peaks 1. 21 Rows used for Target Duration Curve Calculation 50% of 2 year predev.tsf + 2 year offsite.tsf 0.0975 + 0.1560 = 0.2535 cfs <-first interval 50 year flow: 50 year predev.tsf + 50 year offsite.tsf 0.557 + 0.350 -0.907 cis Interval Size: (50 year -first interval) / 35 (0.907 -0.2535}/35 0.01867 42 1. 21 0.1'" 1 43 1.18 0.15,1 44 1. 1.5 0.131 40 1 . 12 0.111 46 1.10 0.091 47 1. 88 0.071 48 1. 05 0.051 49 1. 03 0.031 50 1. 01 0.011 100.00 0.990 50.00 0.980 25.00 0.960 10.00 0.900 8.00 0.875 5.00 0.800 2.00 0.500 1. 30 0.231 Vault Detention Facility Retention/Detention Facility Type of Faci:ity: Facility Length: Facility Width: Facility Area: Effective Storage Depth: Stage 0 Elevation: Storage Volume: Riser Head: Riser Diameter: Number of orifices: Orifice # Height (ft) 1 0.00 2 5.00 3 5.90 DeteoI.ion 103.00 93.00 9579. 8.00 0.00 76632. 8.00 18.00 3 Diameter (in) 2.00 1. 38 2 _ 13 Top Notch Weir: None Outflow Rating Curve: None S'(age Elevation Storage Vault ft ft sq. ft ft ft cu. ft ft inches Full Head Pipe Discharge (CFS) 0.307 0.089 0.177 Di amet_er (in) 4.0 6.0 Discharge Percolation (ft) (ft) (cu. ft) (ac-ft) (ets) (cfs) 0.00 0.00 O. 0.000 0.000 0.00 0.02 0.02 192. 0.004 0.016 0.00 0.04 0.04 383. 0.009 0.022 0.00 0.06 0.06 575. 0.013 0.027 0.00 0.08 0.08 766. 0.018 0.031 0.00 0.10 0.10 958. O. 022 0.035 0.00 0.13 0.13 1245. 0.029 0.038 0.00 0.15 0.15 1437. 0.033 0.041 D.DC 0.17 0.17 1628. 0.037 0.044 0.00 0.19 0.19 1820. 0.042 0.047 0.00 0.34 0.34 3257. 0.075 0.064 0.00 0.50 0.50 4790. 0.110 0.077 0.00 0.66 0.66 6322 . 0.145 0.088 0.00 0.81 0.81 7759. 0.178 0.098 0.00 0.97 0.97 9292. 0.213 0.107 0.00 i.13 1.13 10824. 0.248 0.115 0.00 1. 29 1. 29 12357. 0.284 0.123 0.00 1. 44 1. 44 13794. 0.317 0.130 0.00 1. 60 1. 60 15326. 0.352 0.137 0.00 1. 76 1. 76 16859. 0.387 0.144 0.00 1. 91 1. 91 18296 . 0.420 0.150 0.00 2.07 2.07 19829. 0.455 0.156 0.00 2.23 2.23 21361. C.490 0.162 0.00 2.38 2.38 22798. 0.523 0.168 0.00 2.54 2.54 24331. 0.559 0.173 0.00 2.70 2.70 25863. 0.594 0.178 0.00 2.85 2.85 27 300. 0.627 0.183 0.00 3.01 3.01 28833. 0.662 0.188 0.00 3.17 3. 17 30365. 0.697 0.193 0.00 3.32 3.32 31802. 0.730 0.198 0.00 3.48 3.48 33335. 0.765 0.202 0.00 3.64 3.64 34868. 0.800 0.207 0.00 3.80 3.80 36400. 0.836 0.211 0.00 3.95 3.95 37837. 0.869 O.21E 0.00 4.11 4. 11 39370. 0.904 0.220 0.00 4.27 4 .42 4 .08 4 .74 4 .89 5.00 5.01 5.03 5.04 5.06 5.07 5.09 5.10 5.11 5.13 5.29 5.44 5.60 5.76 5.90 5.92 5.94 5.97 5.99 6.01 6.03 6.05 6.08 6.10 6.26 6.41 6.57 6.73 6.88 7.04 7.20 7.35 7.51 7.67 7.82 7.98 8.00 8.10 8.20 8.30 8.40 8.50 8.60 8.70 8.80 8.90 9.00 9.10 9.20 9.30 9.40 9.50 9.60 9.70 9.80 4. ' 4. 2 4. 8 4. 4 4.89 S.CO 5.01 5.03 5.04 5.06 5.07 5.09 5.10 5.11 5.13 5.29 5.44 5.60 5.76 5.90 5.92 5.94 5.97 5.99 6.01 6.03 6.05 6.08 6.10 6.26 6.41 6.57 6.73 6.88 7.04 7.20 7.35 7.51 7,67 7.82 7.98 8.00 8.10 8.20 8.30 8.40 8.50 8.60 8.70 8.80 8.90 9.00 9.10 9.20 9.30 9.40 9.50 9.60 9.70 9.80 409:.12. 42339. 43872. 45404. ';684l. 47895. 47991. 48182. 48278. 48470. 48566. 48757. 48853. 48949. 49140. 50673. 52110. 53642. 55:75. 56516. 56708. 56899. 57187. 57378. 57570. 57761. 51953. 58240. 58432. 59965. 61401. 62934. 64467. 65904. 67436. 68969. 70406. 71938. 73471. 74908. 76440. 76632. 77590. 78548. 79506. 80464. 81422. 82379. 83337. 84295. 85253. 86211. 87169. 88127. 89085. 90043. 91001. 91958. 92916. 93874. Hyd Inflow Outflow Peak 0,939 0.224 'J.972 0.228 1.007 0.232 1.042 0.2:36 1,075 0.240 1.100 0.243 1.]02 0.243 1.106 0.245 1.108 0.247 1.113 0.250 1.115 0.254 1.119 0.259 1.122 0.261 1.124 0.263 ] .]28 0.264 1.1E3 0.277 1.196 0.287 1.231 0.296 1.267 0.305 1.29'/ 0.312 1.302 0.314 1.306 0.319 1.313 0.326 1.317 0.335 1.322 0.346 ] .326 0.359 1.330 0.368 1.337 0.372 1.341 0.376 1.377 0.402 1.410 0.423 1.445 0.443 1.480 0.460 1.513 0.477 1.548 0.492 1.583 0.507 1.616 0.521 1.651 0.534 1.687 0.547 1. 720 0.560 1.755 0.572 1.759 0.573 1.781 1.040 1.803 1.890 1.825 3.000 1.847 4.300 1.869 5.770 1.891 7.210 1.913 7.740 1.935 8.240 1.957 8.710 1.979 9.150 2.001 9.580 2.023 9.980 2.045 10.370 2.067 10.740 2.089 11.100 2.111 11.450 2.133 11. 780 2.155 12.110 Storage ::', JO 0.80 [I. :](1 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Target Calc Stage Elev leu-Ft) IAc-Ft) 1 5 6 7 8 1.63 ** ... * ...... ..- 1.'34 0.79 2.87 **,,* ... *,.. 2.~6 ****""*"" 1.61 ... ****** 2.03 *~H'-!d' 1.35 ******* 1.3-1 *"'***** 0.81 2.05 0.70 2.03 0.54 7,56 0.48 6.90 0.47 6.79 0.39 6.20 0.22 3.99 0.19 3.15 Route Time Series through Facility 8.05 9.0.1 "I.~6 6.90 6.79 6.20 3.99 3.1S Inflow Time Series File:devcombined.tsf Outflow Time Series File:rdout. 77114, 76893. 724?9. 66087. 65·075. 59425. 38197. 30166. Inflow/Outflow Analysis Peak Inflow Discharge: Peak Outflow Discharge: Peak Reservoir Stage: 2.87 eFS at 6:00 on Jan 0.808 ers at 19:00 on Feb 8.05 Ft Peak Reservoir Elev: 8.05 Ft Peak Reservoir Storage: 77114. Cu-Ft 1.770 Ac-Ft 1.7 is 5 1.6 r: 1 1. 517 1. 4 94 1. 364 0.877 0.693 9 in 1990 9 in 1951 Flow Frequency Analysis Time Series File:rdout.tsf Project Location:Sea-Tac LogPearson III Coefficients Mean= -0.604 StdDev= 0.181 Skew= 1.288 ---Annual Peak Flow Rates--- Flow Rate leFS) 0.194 0.240 0.808 0.170 0.188 0.222 0.237 0.291 0.212 0.225 0.199 0.527 0.215 0.160 0.218 0.203 0.228 0.196 0.231 0.198 0.194 0.201 0.233 0.393 0.214 0.224 0.229 0.228 0.152 0.211 0.159 0.462 0.192 0.479 Rank 38 13 1 46 42 24 15 12 29 22 33 5 27 47 25 31 21 35 18 34 37 32 16 11 28 23 19 20 49 30 48 8 39 6 ':'ime of Peak 2/17149 3/05/50 2/09/51 1130/52 1/12/53 1/06/54 2/08/55 12/22/55 12/09/56 1/17/58 1/24/59 11/21/59 11/24/60 1/03/62 11126/62 1/01/64 12/01164 12/28/65 12/13/66 1/20/68 12/04/68 1114/70 12/07/70 2/28/72 12/27 /72 1116/74 12/27/74 12104/75 8126/77 12115/77 11/19/78 12/17/79 12/27 /80 10/06/81 3:00 7:00 19:00 14:00 7:00 8:00 6:00 15:00 20:00 7:00 10:00 2:00 17:00 8:00 10:00 23:00 8:00 18:00 15:00 19:00 0: 00 15:00 5:00 18:00 19: 00 18:00 8:00 2:00 6:00 19:00 9:00 20:00 8:00 18:00 -----Flow Frequency Analysis------- - -Peaks - -Rank Return Prob leFS) (h) Period 0.808 8.05 1 89.50 0.989 0.702 0.538 0.531 0.527 0.479 0.467 0.462 0.433 0.399 0.393 0.291 0.240 0.239 0.237 0.233 0.231 0.231 0.229 0.228 0.228 0.225 0.224 0.222 0.218 0.217 0.215 0.214 0.212 0.211 0.203 0.201 0.199 0.198 8.03 7.56 7.47 7.42 6.9C 6.79 6.49 6.24 6.20 5.50 4.89 4.84 4.79 4.61 4.55 4.53 4.46 4.43 4.41 4.31 4.28 4.18 4.05 3.99 3.91 3.88 3.84 3.81 3.51 3.43 3.36 3.32 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 32.13 19.58 14.08 10.99 9.01 7. 64 6.63 5.86 5.24 4.75 4.34 3.99 3.70 3.44 3.22 3.03 2.85 2.70 2.56 2.44 2.32 2.22 2.13 2.04 1. 96 1. 89 1. 82 1. 75 1. 70 1. 64 1. 59 1. 54 1. 49 0.969 0.949 0.929 0.909 0.889 0.869 0.849 0.829 0.809 0.789 0.769 0.749 0.729 0.709 0.690 0.670 0.650 0.630 0.610 0.590 0.570 0.550 0.530 0.510 0.490 0.470 0.450 0.430 0.410 0.390 0.370 0.350 0.330 0.231 17 0.177 44 0.190 40 0.399 10 0.467 7 0.184 43 0.176 45 0.538 3 0.531 4 0.217 26 0.189 41 0.145 SO 0.239 14 0.702 2 0.433 9 0.195 36 Computed Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks 1/05/83 16:00 12/10/83 18, OC ll/U4/84 O:OC 1/18/86 23,OC :C1/24/86 'J /15/88 ,1/05188 1109/90 4/05/91 1131/92 3/23/93 12/01/93 2120195 2/09/96 1102197 10130/97 8:0C 6:0C 21:00 12,00 6,00 6:00 7:00 16,00 0:00 3,00 12:00 10:00 0.196 0.195 0.194 0.194 0.192 O. 'J 90 0.189 0.188 0.184 0.177 0.176 0.170 0.160 0.159 0.152 0.145 0.945 0.754 0.598 0.435 0.408 0.336 0.228 0.180 3.25 3.23 3.20 3.19 3.15 3,07 3.06 3.01 2.89 2,66 2.62 2.45 2.18 2.15 1.96 1. 77 B.C8 8.04 8.01 6.50 6.30 5.99 4.43 2.77 Flow Duration from Time Series Fi1e:rdout.tsf 35 3E- 3'! 38 39 40 41 42 43 44 45 46 47 48 49 50 1. 45 1. 41 1.3'1 1. 33 1. 30 ] .7.7 1. 24 1. 21 1.18 1 . 15 1. 12 1.10 1. 08 1. 05 1. 03 1. 01 100.00 50.00 25.00 10.00 8.00 5.00 2.00 1. 30 Cutoff Count Frequency cor Exceedence Probablilty CFS 0.012 290621 0.034 33639 0.057 34530 0.080 26545 0.102 18546 0.125 13130 0.148 8714 0.171 5099 0.193 3316 0,216 ]908 0.239 1128 0.262 134 0.284 154 0.307 163 0.330 78 0.353 14 0.375 27 0.398 44 0.421 28 0.444 43 0.466 42 0.489 26 0.512 18 0.535 29 0.557 13 0.580 8 0.603 0 0.625 0 0.648 0 0.671 0 0.694 0 0.716 ] 0.739 0 0.762 1 0.785 0 66.352 7.680 7.884 6.061 4.234 2.998 1. 989 1.164 0.757 0.436 0.258 0.031 0.035 0.037 0.018 0.003 0.006 0.0]0 0.006 0.010 0.010 0.006 0.004 0.007 0.003 0.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 66.352 74.032 81.916 87.976 92.210 95.208 97.197 98.362 99.119 99.554 99.812 99.842 99.878 99.915 99.933 99.936 99.942 99.952 99.908 99.968 99.978 99.984 99.988 99.995 99.997 99.999 99.999 99.999 99.999 99.999 99.999 100.000 100.000 100.000 100.000 % 33.648 25.968 18.084 12.024 7.790 4.792 2.803 1. 638 0.881 0.446 0.188 0.158 0.122 0.085 0.067 0.064 0.058 0.048 0.042 0.032 0.022 O. OlE 0.012 0.005 0.003 0.001 0.001 0.001 0.001 0.001 0.001 0.000 0.000 0.000 0.000 0.336£+00 0.260£+00 0.181£+00 O.120E+OO O.779E-Ol 0.479£-01 0.280£-01 0.164£-01 0.881£-02 0.446£-02 0.:88£-02 O. '58£-02 0.122E-02 0.852£-03 0.674£-03 0.642£-03 0.580£-03 0.479£-03 0.416£-03 0.317£-03 0.221£-03 0.162£-03 0.121£-03 0.548£-04 O.251E-04 0.685E-C5 0.685£-05 0.685£-05 0.685E-05 0.685E-05 0.685E-05 0.457£-05 0.457E-05 0.228E-05 O.228E-05 0.310 0.291 0.2"71 0.251 0.231 0.21] 0.191 0.171 0.151 0.13 ] 0.111 0.091 0.071 0.051 0.031 0.011 0.990 0.980 0.960 0.900 0.875 0.800 0.500 0.231 0.80'/ ~ 0 ~ in 0 R ~ I> t ~ ~ 0 00' 00 ~ 0 o o 10' " '--.... ~'" Ii "i I 10 -5 o.oeo Duration Comparison Anaylsis Base File: predevcombined.tsf New File: rdout.tsf Cutoff Units: Discharge ir. CFS O.oon iii '" 10 -3 J.':2SE-05 i i 1~'-.2 -----F:c:action of Time--------------Check of Tolerance------- Cutoff Base New ~Change Probability Base 0.253 0.19E-02 0.16E-02 -14.4 0.19E-02 0.253 0.299 o .l1E-02 0.97E-03 <1. 0 o .l1E-02 0.299 0.344 0.66E-03 0.66E-03 -1.4 0.66E-03 0.344 0.390 0.43E-03 0.52E-03 20.1 0.43E-03 0.390 0.435 0.29E-03 0.35E-03 20.3 0.29E-03 0.435 0.481 0.18E-03 0.17£-03 -5.0 0.18E-03 0.481 0.526 0.98E-04 0.75E-04 -23.3 0.98E-04 0.526 0.572 0.62E-04 0.l1E-04 -81. 5 0.62E-04 0.572 0.618 0.37E-04 0.68E-05 -81. 3 0.37E-04 0.618 0.663 0.16E-04 0.68E-05 -57.1 0.16E-04 0.663 0.709 0.14E-04 0.46E-05 -66.7 0.14E-04 0.709 0.754 0.l1E-04 0.46E-05 -60.0 o .l1E-04 0.·) 54 0.800 0.91E-05 0.23E-05 -75.0 0.91E-05 0.800 0.845 0.23E-05 O.OOE+OO -100.0 0.23E-05 0.845 Maximum positive excursion = 0.028 cis 7.3%) occurring at 0.391 cfs on the Base Data:predevcombined.tsf and at 0.420 cfs on the New Data:rdout.tsf Maximum negative excurSlon = 0.236 cfs (-29.1%) occurring at 0.812 cfs on the Base Data:predevcombined.tsf and at 0.576 cfs on the New Oata:rctout.tsf New ~Change 0.239 -5.8 0.292 -2.3 0.334 -2.9 0.415 6.6 0.450 3.3 0.477 -0.9 0.520 -1. 1 0.531 -7.1 0.548 -11. 3 C.568 -14.3 0.569 -19.7 0.572 -24.2 0.576 -27.9 0.808 -4.4 , I ,,:\(>\_ dm ~I t€lrgel dd' +1 APPENDIX B Geotechnical Report Earth Solutions NW, LLC Earth Solutions NWllC (3cotcchnical Engineering Geology Etl\'irolllllttltal Scientists Construction i\'1onitoring GEOTECHNICAL ENGINEERING STUDY PROPOSED PANTHER LAKE RESIDENTIAL SUBDIVISION 18647 - 1 08TH AVENUE SOUTHEAST RENTON, WASHINGTON ES-2995 PREPARED FOR The Conner Homes Group, LLC September 23, 2013 Hen T. Wright, E.I.T. Staff Engineer Kyle R. Campbell, P.E. Principal GEOTECHNICAL ENGINEERING STUDY PROPOSED PANTHER LAKE RESIDENTIAL SUBDIVISION 18647 -108TH AVENUE SOUTHEAST RENTON, WASHINGTON ES-2995 Earth Solutions NW, LLC 1805 _136TH Place Northeast, Bellevue, Washington 98005 Ph: 425-284-3300 Fax: 425-449-4711 1-866-336-8710 ImpoNant Information About Your Report r . " I I I : I ;' ILl .' I ( ~ I '" -I ~ ~. ":' ", If • I I t I,' I I ')i '" \ r :' , '; I , c., GlatldIicII SIPvIc8s Are ParIol'lllllll .... SIIacIIc PuPllIIIII, P .... 11 .. , .. d ...... GeotecIlnical engineers slnJcture their services to meet the specHic needs of their clients. A geotechnical engineering study conducted for a civil engi- neer may not fulfill the needs of a construction corrtJactor or even another civil engineer. Because each geotechnical engineering study is unique, each geotechnical engineering report is unique, prepared sole/ytor the client. No one except you should rely on your geotecllnical engineering report without first comrring with the geotechnical engineer v.tJa prepared It fJIId no one -not even yuu -should iljlply the report for any purpose or project except the one originally conte~laIed. RlllllIIII flllllIIIIIPt Serious problems have occurred because those relying on a geotechnical engineering report did not read K all. Do nat rely on an 8)(6Cutive summary. Do not read selected elements only. I aln.'.! PI ( ) 1lI~ 11I11I8II11 I ~ _. II "lIlea FICbII'I Geotechnical engineers consider a number of unique, project-specHic fac- tors wilen establishing the scope of a study. Typical factors include: the clienfs goals, objectives, and risk management preferences; the general nature of the sIruclure involved, its size, and configuration; the locallon of !he structure on the site; and other planned or existing site improvements, such as access roads, parking lots, and underground utiinies. Unless the geotechnical engineer who conducted the study specifically indicales 0th- erwise, do not rely on a geotechnical engineering report that was: • not prepared for you, • not prepared for your project, • not prepared for !he specHic site explored, or • completed before important project changes were made. Typical changes that can erode the reliability of an existing geotechnical engineering report include those that affect: • !he furdion of the proposed structure, as when it's changed from a parking garage ID an office building, or from a light indusb'ial plant to a refrigerated wareOOuse, • elevation, configuration, localion, orientation, or weight of the proposed sb'ucture, • compos~ion of the design team, or • project ownership. As a general rule, always inform your geotechnical engineer of project changes---wen minor ones---,md request an assessment of !helr impact. GeoIBchnical engineers cannot accept responsibility or liability for pro/Jlerns /hat occur because their flI/XJtIs do not consider developmerrts at which they were not inlorrrJid. SdI Cr_ CIndIIIuII c. cas. A geotechnical engineering report is based on conditions that existed at the time the study was perfomned. 00 notmly on a geotechnical engifllJllf- ing repotIwhose adequacy may have been affected by: the passage of time; by man-made events, such as construction on or adjacent to the site; or by natural events, SlJch as floods, earthquakes, or groundwater fluctua- tions. Always contact the geotechnical engineer before applying the report to detemnlne if It Is still reliable. A minor amount of additional testing or analysis could prevent major problems. MIlt GIIt8cbIIcaI ns II APe PraIaBIIIInII 111*111111 S~ exploration identifies subsurface conditions only at those points where subsurfa;e tests 1Ie conducted or ~Ies are taken. Geotechnical engi- neers review field and laboratory data and then apply their professional judgment to render an opinion about subsurface conditions throughout the s~. Actual subsurface cond~ions may differ-sometlmes significantly- from those indicated in your report. Retaining the geotechnical engineer who developed your report to provide construdion observation is the most Bffa:Iive method of managing the risks associated with unanticipated condltions. I HI_I.rl R.~ 2 II1II:11118 API MIt F-.. Do not overrely on the conslructian recommendaJions included in your report. Those recommendations ilffi not final, because geotechnical engi- neers develop them principally from judgment and opinion. Geotechnical engineers can finalize their recommendations only by observing actual subsurtace coMmons revealed during construdion. The geotechnical engineer who developed)OO( repoI/ cannot assIJITlIlIIS{IOIIsibility or liability for the fBIIOII's recrxrmendalions if that engineer does not perform construction obseIvaIion A GaotacbnIcaI filii I IDa Repapt Is Sub)lct to MII ... • ... 1IIIDn Other design team members' misiOOlrpretllion of geotechnical engineering reports has resulted in cosily problems. lnMir that risk by having your ge0- technical engineer confer wilh ~propriale members of the design team alter swmilting 1he report. AIsc retail your geotechnical engineer to review perti- nent elements of Ihe cI1slgn team's plans and specffIcaIons. Contractors can also misin1llrpret a geotechnical engineering report Reduce that risk by having your geotechnical engineer participate in prebid and preconstrudiOn conferences, and by providing construction observation. III Not IWi ...... _" .. ·1 ...... Geotechnical engineers prepare final bOring and testing logs based upon their interpretation of field logs and laboratory data. To prevent errors or omissions, the logs included in a geotechnical engineering report should never be redrawn for Inclusion in architectural or other design drawings. Only photographic or electroniC reproduction is acceptable, but recognize that separaUng logs from the repoIt can eleVIIIB risk. GIVe CIInII'actIIn I CIIIpIeI8 88PII'11IHI ..... Some owners and design professionals mistakenly believe they can make contractors liable for unanticipated sWsurtace conditions by limmng vAlat they provide for bid preparation. To help prevent cosily problems, give con- tractors the complete geotechnical engineering report. butprelace n wnh a clearly written leiter of lransmillal. In that leiter, advise contractors that llie report was not prepared for purposes 01 bid development and thai the report's accuracy is limned; encourage them to confer with Ihe geotechnica engineer who prepared the report (a modest fee may be required) and/or to conduct additional study to ob1ain Ihe SpecifIC types of information they need or prefer. A prebld conference can also be valuable. Be SlIfe contrac- lOis have Sllfficient time to perform additional study. Only then might you be in a posttion to give contJactors the best InfomJallOll avai lable to you, while requiring them to at least share some of the financial responsibilities stemming from unanticipated condttlons. I11III RIIIPllla' my PI .. lalolll CIIIIIJ Some clients, design professionals, and contractors do not recognire thai geotechnical engineering is far less IOOICI than other engineering disc~ ptines. This lack of understanding has created unrealistic expectations thai have led to disappointments, claims, and disputes. To help reduce the risk of such outcomes, geotechnical engineers commonly include a variety of explanatory provisiOOs in their reports SomeHmes labeled "limitations" many of lliese provisions indicate where geotechnical engineers' responsi- bilities begin and end, to help others recognizE their own responsibiltties and risks. Read these provisions closely. Ask questions. Your geotechnical engineer should respond fully and frankly. GIIenvIPDII ... '" CllcePa API Not CUVII'ad The equipment techniques, and personnel used to pertomn a geoenviron- menial study differ significantly from those used to pertomn a geotechnical study. For that reason, a geotechnical engineering report does not usually relate any geoenvironmenlal findings, conclusions, or recommendations; e.g., about the likelihood of encountering underground storage tanks or regulated contaminants. Unanticipated environmental problems have led to numerous project failures. H you have not yet obtained your own geoen- vironmentallnformation, as!< your geotechnical consuttant for risk man- agement guidance. Do not rely on an environmental report prepared for somoone else. 0bIIIn PI'II8IIIGIIII All ..... TD DIll wIIb MaId Diverse strategies can be applied during building design, COnstruCtiOll, operation, and maintenance to prevent significant amounts of mold from growing on indoor surtaces. To be effective, all such strategies should be devised for the express fJUf1IOSli of mold prevention, Integrated into a com- prehensive plan, and executed with diligent oversigflt by a professional mold prevention consultant. Because justa small amount of water or moisture can lead to the development of severe mold infestations, a num- ber of mold prevention strategies focus on keeping building surtaces dry. While groundwater, water infinration, and similar issues may have been addressed as part of the geotechnical engineering study whose findings are conveyed ilTthis report, the geotechnical engineer In charge of this project is not a mold prevention consultant none III the BSIrII:Is fIBT- formed In connec1fon wltlllII, g,oIBJ:/IIIlc/Il "",neer's study wetII dell/gned or t:tJ/IIIucIed trJr IhIl PIJlflOBll of mold prelffln- non. P/IJpfIr Impl,m"""'/on of III. rmm/lllflldattDIIS t:I1fIWysd In IIIls rep,", will not III finN lIB ",,"rle'" to """"", mllftl from growing In or on lire BInII:tut8 Inrolr!erl. Rely, 011 '-Afi.MInJIa' GIuIIcIIICIIIII EnaIMIP .. ft 1711uuii1 AiiIIIbIICI Membership In ASFE/The Best People on Earth exposes geotechnical engineers to a wide array of risk managanent techniques that can be of genuine benefit for everyone involved wnh a construction project. Conler willi you ASFE-member geotechnical engineer for more information. ASFE n ......... II •• IIrlt 8811 Colesville Road/Suite Gl06, Silver Spring, MD 20910 Telephone: 301/565-2733 Facsimile: 3011589-2017 e-mail: info@asfe.org www.asle.org CDpYftlht 2004 /1y ASH. Int:. DupI/t:aIkHr, ff/NfIfIU<fIOn. or oopy/rIQ of fills tIoi:!JmInt, iIr ." ... or In parl; /1y 1lIIY .,..,.. whirs"""" & strlcttt __ , __ oIIh ASJn 9PfIII/kIorIIten pom!Is8iDtI. ~ quoI/ng, or ___ wmiIrII from rfI/S docu"",nt Is pamJlllBd oniy _ 1iIII_ -. permission or ASFE, ... oniy lor PUf[JOfeS of BCho/aJty """""" or"'" -. ~ ~ of ASFf nwy ... rfI1s docummrl'" ~ to or IS III _ of. f}IIOMI:ImIcaJ "'fI/neerlrIg __ Any otIJfr fItm, 1ndMduIlI, or 0IIw InfIIy that SO uses this docllmlllt without being In ASFE member could b8 committing ntgIIgBnt or intentional (fralJdullJnt) mlsllpmant2tian. IIGERII6O>I5.0N September 23,2013 ES-2995 The Conner Homes Group, LLC 846 _108th Avenue Northeast Bellevue, Washington 98004 Attention: Ms. Jieun Shon Dear Ms. Shon: Earth Solutions NW LLC • Geotechnical Engineering • Construction Monitoring • Environmental Sciences Earth Solutions NW, LLC (ESNW) is pleased to present this report titled "Geotechnical Engineering Study, Proposed Panther Lake Residential Subdivision, Renton, Washington". This study has been prepared to address the feasibility of the proposed development from a geotechnical standpoint. The proposed 33 residential lot development is bordered to the west by an off-site steep slope. Based on the conditions observed during our fieldwork, the subject site is underlain primarily by native soils consisting of medium dense to very dense glacial till. Groundwater seepage was observed in one test pit at a depth of approximately five feet below existing grade. Based on the results of our study, the proposed development is feasible from a geotechnical standpoint. The residential buildings and associated structures can be supported on a conventional foundation system bearing on competent native soil or structural fill. Where loose or unsuitable soil conditions are exposed at foundation subgrade elevations, compaction of the soils to the specifications of structural fill, or overexcavation and replacement with structural fill, may be necessary. This report provides recommendations for critical areas assessment, foundation design, structural fill recommendations, and other geotechnical recommendations. The opportunity to be of service to you is appreciated. If you have any questions regarding the content of this geotechnical engineering study, please call. Sincerely, EARTH SOLUTIONS NW, LLC \A--l ( ~ Henry T. Wright, E.I.T. Staff Engineer 180S -1:lbth Place N.E .• Suite 20') • Bellevue. WA 98005 • (425) 449-4704 • FAX (425) 449-4711 TABLE OF CONTENTS ES-2995 PAGE INTRODUCTION ........................................................................ 1 General .................................................................... ...... 1 Project Description ........................................................... 2 Surface ............................................................................ 2 Slope Reconnaissance... ... .... .............. ...... ...... ...... ............. 2 Subsurface... .................................................................... 3 Groundwater..................................................................... 3 CRITICAL AREAS AND GEOLOGIC HAZARDOUS AREAS ASSESSMENT............................................................................. 3 Site and Construction Plans..... ..... .......... ....... .......... ............... ..... 3 Landslide Hazard... ............................................................. 3 Steep Slopes........................................................................ 4 Erosion Hazard.......... ...... ...... ..... .... ............ ....... ...... ......... ... 4 !!:..!.!!.!!~~ ................................ . 5 5 DISCUSSION AND RECOMMENDATIONS ....................................... 5 General ............................................................................. 5 Site Preparation and Earthwork............................................ 6 Erosion Control................................................................... 6 In-Situ Soils.............................................................. ............ 6 Wet Season Grading...... ............ .... ............... .... ..... ........ ..... 6 Structural Fill........... ...... ...... .... ... ...... ..................... .............. 7 Excavations and Slopes...................................................... 7 Foundations...................................................................... 7 Seismic Considerations. ............ .... ..... ... ................................ 8 Slab-on-Grade Floors.................................................... ...... 8 Retaining Walls............ ... ......... ......... .......................... ....... 8 Drainage ............................................................................ 9 Utility Trench Backfill.......................................................... 9 Pavement Sections......... ... ......... ... ... ...... ... ... ....... ... ... ... ...... 10 LIMITATIONS .............................................................................. 10 Additional Services ......................... ,. ......... ...... ... ... ... ... ... ... 10 Earth Solutions 1m. LLC GRAPHICS PLATE 1 PLATE 2 PLATE 3 PLATE 4 APPENDICES Appendix A Appendix B TABLE OF CONTENTS Continued ES-2995 VICINITY MAP TEST PIT LOCATION PLAN RETAINING WALL DRAINAGE DETAIL FOOTING DRAIN DETAIL Subsurface Exploration Test Pit Logs Laboratory Test Results Sieve Analysis Results earth Solutions 1m, LLC General GEOTECHNICAL ENGINEERING STUDY PROPOSED PANTHER LAKE RESIDENTIAL SUBDIVISION RENTON, WASHINGTON ES·2995 INTRODUCTION This geotechnical engineering study was prepared for the proposed 33 lot residential development at 18647 -1081h Avenue Southeast in Renton, Washington. The purpose of this study was to prepare geotechnical recommendations for the proposed development. To complete the scope of services detailed in our proposal PES-2995 dated August 20, 2013, we performed the following: • Subsurface exploration and characterization of soil and groundwater conditions by way of test pits excavated on the accessible areas of the site; • Laboratory testing of soil samples obtained during field exploration; • Engineering analyses, and; • Preparation of this report. The following documents and/or resources were reviewed as part of our report preparation; • Geologic Map of the Renton Quadrangle; • Conceptual Site Plan Provided by the Client, dated May 28,2013; • The City of Renton online GIS property research database, and; • City of Renton Critical Areas Regulations (4-3-050J). Earth Solution. NW. ltC The Conner Homes Group, LLC September 23,2013 Project Description ES-2995 Page 2 Based on the plans provided to us, the site will be developed with 33 single family residential lots with associated roadways and stormwater facilities. Based on the City of Renton GIS data, sensitive and protected slopes are located along and adjacent to the western margins of the subject site. Grading activities will likely include cuts and fills to establish the planned building lots and access roadway alignments. Site improvements will also include underground utility installations and construction of stormwater detention facilities. Based on the conceptual site plan provided to us, we estimate cuts and fills to establish finish grades throughout the site will be on the order of two to eight feet on average; however, grading plans were not available at the time this report was prepared. Engineered rockeries or modular block walls may also be utilized as part of the overall grading plan. A storm tract is mapped along the western portion of the site. We anticipate the proposed residential structures will consist of relatively lightly loaded wood framing supported on conventional foundations. Based on our experience with similar developments, we estimate wall loads on the order of 2 kips per linear foot and slab-on-grade loading of 150 pounds per square foot (pst). If the above design assumptions are incorrect or change, ESNW should be contacted to review the recommendations in this report. ESNW should review the final design to verify that our geotechnical recommendations have been incorporated into the plans. Surface The subject site is located south of Southeast 186!h Street at 18647 -108!h Avenue Southeast in Renton, Washington, as illustrated on the Vicinity Map (Plate 1). The site consists of six parcels totaling approximately 7.18 acres and is comprised of forested land through the northwestern and southwestern portions of the site with multiple residential structures and cleared land in the central and northeast portions of the site. Topography of the site consists of a slight west facing slope which becomes moderate to steep at the western margins of the site. The Test Pit Location Plan (Plate 2) illustrates the approximate limits of the property. Slope Reconnaissance During our fieldwork, we performed a visual slope reconnaissance across portions of the steep slope areas of the site as well as off-site to the west. The main focus of our reconnaissance was to identify signs of instability or erosion hazards along the slope areas. The typical instability indicators include such features as; head scarps, tension cracks, hummocky terrain, groundwater seeps along the surface and erosion features such as gulleys and rills. During the slope reconnaissance, a gulley aligned perpendicular to Panther Creek was observed adjacent to the northwest corner of the site, as well as a shallow head scarp approximately six to eight feet in height west of the property margins indicating minor surficial instability. In general, based on the slope reconnaissance, stability of the slope areas can be characterized as moderate. Earth Solu!ion. NW. LLC The Conner Homes Group, LLC September 23,2013 Subsurface ES-2995 Page 3 As part of the subsurface exploration, six test pits were excavated on accessible portions of the site for purpose of assessing the soil conditions. Please refer to the test pit logs provided in Appendix A for a more detailed description of the subsurface conditions. Topsoil was encountered to an average approximate depth of 6 to 12 inches. Underlying the topsoil, medium dense brown sandy silt and silty sand was observed (Unified Soil Classification ML and SM, respectively), transitioning to dense to very dense at an average depth of three to five feet below existing grades. The referenced geologic map of the area identifies glacial till (Qgt) across the site. The soil conditions observed at our test sites generally correlate with glacial till (Qgt). Groundwater Groundwater seepage was encountered during our fieldwork at test pit TP-4. The seepage was observed at approximately five feet below existing grade and likely represents perched groundwater. The presence of groundwater seepage should be expected in deeper site excavations such as deeper foundation and utility trench excavations. Groundwater seepage rates and elevations fluctuate depending on many factors, including preCipitation duration and intensity, the time of year, and soil conditions. In general, groundwater elevations and flow rates are higher during the wetter, winter months. CRITICAL AREAS AND GEOLOGIC HAZARDOUS AREAS ASSESSMENT As part of this geotechnical engineering study and critical areas report, the City of Renton Critical Areas Regulations (4-3-050J) were reviewed. Per the City of Renton Critical Areas Regulations requirements, the following topics related to development plans and site conditions are addressed. Site and Construction Plans The attached Test Pit Location Plan (Plate 2) illustrates a conceptual layout of the proposed 33 residential lot development. The building pad elevations will vary according to existing grades. We anticipate the maximum cuts for the proposed development will be on the order of six to eight feet. A storm tract is mapped along the western margins of the site, adjacent to off-site steep slopes. Based on review of the referenced section of the City of Renton Municipal Code, as well as City of Renton GIS data, landslide hazards, steep slopes, and erosion hazards are considered for the subject development. Landslide Hazard With respect to landslide hazard areas, Part 4-3-050J-1b of the City of Renton Critical Areas Regulations defines landslide hazard areas as the following: Earth Solutions NW, LLC The Conner Homes Group, LLC September 23,2013 • Low Landslide Hazard: Areas with slopes less than 15 percent. ES-2995 Page 4 • Medium Landslide Hazard: Areas with slopes between 15 percent and 40 percent and underlain by soils that consist largely of sand, gravel or glacial till. • High Landslide Hazards: Areas with slopes greater than 40 percent and areas with slopes between 15 percent and 40 percent and underlain by soils consisting largely of silt and clay. • Very High Landslide Hazards: Areas of known mappable landslide deposits. The off-site natural slope adjacent to the western margins of the site is not mapped as a landslide hazard by the City of Renton GIS data, however, based on a greater than 40 percent slope condition it is considered a high landslide hazard by the City of Renton Critical Areas Regulations. As previously described in the Slope Reconnaissance section of this study, a head scarp approximately six to eight feet in height was observed along the off-site natural slope, indicating recent, minor surficial instability. However, as the slope is underlain by glacial till, the overall global stability of the slope areas can be characterized as moderate. Steep Slopes With respect to steep slope critical areas, the referenced section of the Renton Code defines steep slopes as follows: • Sensitive Slopes: Areas with slopes between 25 percent and 40 percent. • Protected Slopes: Areas with slopes greater than 40 percent. Based on our observations and review of the City of Renton GIS data, sensitive and protected slopes are present along and adjacent to the western margins of the property. In general, based on the slope reconnaissance, stability of the slope areas can be characterized as moderate. Erosion Hazard With respect to erosion hazard areas, the referenced section of the Renton Code defines erosion hazards as follows: • Low Erosion Hazard: Areas with soils characterized by the Natural Resource Conservation Service as having slight or moderate erosion potential, and that slope less than 15 percent. • High Erosion Hazard: Areas with soils characterized by the Natural Resource Conservation Service as having severe or very severe erosion potential, and that slope more steeply than 15 percent. Earth Solutions NW. LLC The Conner Homes Group, llC September 23,2013 ES-2995 Page 5 The off-site sloped areas adjacent to the western margins of the site would be severely susceptible to erosion, in our opinion. However, the on-site sloped areas and areas adjacent to the top of off-site slopes are classified as a low erosion hazard and would have a low susceptibility to erosion, in our opinion. In our opinion, the planned development will not increase the erosion hazard at the site, provided appropriate Best Management Practices are implemented during the earthwork and development activities. General guidelines for erosion control are provided in the Site Preparation and Earthwork section of this study. Analysis of Proposal The planned development activity will involve grading and construction of a 33 residential lot development with associated improvements adjacent to the steep slope area to the west. The proposed development activity will include a storm tract adjacent to the off-site slope area west of the site. As previously described, the on-site slopes and areas adjacent to the top of the off- site slopes exhibit good stability, and the planned development activity will not involve alterations to the areas of 40 percent slope. The proposed development activity is feasible in our opinion, and will not decrease stability of the site or surrounding properties. The project designs must comply with the City of Renton Critical Areas Regulations. Minimum Critical Area Buffer and Setback In our opinion, the proposed development activity can be completed as currently planned without adversely impacting the slope area along and adjacent to the western margins of the site. Sections 4-3-050J5 and 4-3-050J6 specify the requirements for development on sites which contain protected and sensitive slopes. The code requires erosion control measures, slope stabilization, and buffer zones. The proposed storm tract structure(s) to be located adjacent to the steep slope area should be setback at least 25 feet from the top of the slope with grading activities setback at least 10 feet from the top of the slope. Given the overall stable characteristics of the on-site slopes and areas adjacent to the top of off-site slopes, it is our opinion that a 25 foot setback of the proposed storm tract structure/s is feasible from a geotechnical standpoint. DISCUSSION AND RECOMMENDATIONS General Based on the results of our study, in our OpiniOn, construction of the proposed residential development at the subject Site is feasible from a geotechnical standpoint. The primary geotechnical considerations associated with the proposed development include the steep slope setback, foundation support, structural fill placement, and the suitability of the on-site soils for use as structural fill. The proposed structures can be supported on conventional spread and continuous foundations bearing on undisturbed competent native soil or structural fill. Where loose, organic or other unsuitable materials are encountered at or below the footing subgrade elevation, the material should be removed and replaced with structural fill, as necessary. Earth Solutions NW, LLC The Conner Homes Group, LLC September 23,2013 ES-2995 Page 6 This study has been prepared for the exclusive use of The Conner Homes Group, LLC and their representatives. No warranty, expressed or implied, is made. This study has been prepared in a manner consistent with the level of care and skill ordinarily exercised by other members of the profession currently practicing under similar conditions in this area. Site Preparation and Earthwork Grading plans were not available at the time this report was prepared. However, given the existing grades, grading for the new development is anticipated to consist of cuts and fills of up to eight feet. Once the existing vegetation and topsoil has been cleared, grading operations can commence. Erosion Control Temporary construction entrances and drive lanes, consisting of at least one foot of quarry spa lis can be considered in order to minimize off-site soil tracking and to provide a temporary road surface. Temporary slopes and stockpiles should be covered when not in use. Surface water should not be allowed to flow down the face of any natural or cut slope, nor should water be allowed to pond near the top of any slope. Silt fencing should be installed along the margins of the property as well as at the top of on-site slopes of 40 percent or greater. Proper care and measures should be taken to ensure that development does not adversely affect the natural slope areas. Erosion control measures should conform to the Washington State Department of Ecology (DOE) and city of Renton standards. In-situ Soils The soils encountered throughout the majority of the test sites have a moderate to high sensitivity to moisture and were generally In a moist condition at the time of the exploration (September 2013). The soils anticipated to be exposed at this site will degrade rapidly if exposed to moisture. In general, soils encountered during site excavations that are excessively over the optimum moisture content will require aeration or treatment prior to placement and compaction. Conversely, soils that are substantially below the optimum moisture content will require moisture conditioning through the addition of water prior to use as structural fill. An ESNW representative should determine the suitability of in-situ soils for use as structural fill. If the in-situ soils are determined to not be suitable for use as structural fill, use of a suitable imported soil may be necessary. Wet Season Grading If grading takes place during the wetter, winter or spring months, a contingency in the project budget should be included to allow for export of native soil and/or existing fill and import of structural fill as described below. Earth Solutions NW. LLC The Conner Homes Group, LLC September 23,2013 Structural Fill ES-2995 Page 7 Structural fill is defined as compacted soil placed in foundation, slab-on-grade, and roadway areas. Fills placed to construct permanent slopes and throughout retaining wall and utility trench backfill areas are also considered structural fill. Soils placed in structural areas should be placed in loose lifts of 12 inches or less and compacted to a relative compaction of 90 percent, based on the laboratory maximum dry density as determined by the Modified Proctor Method (ASTM 0-1557). For soil placed in utility trenches underlying structural areas, compaction requirements are dictated by the local city, county, or utility district, and in general are specified as 95 percent relative compaction. The upper 12 inches of slab-on-grade and pavement area subgrade should also be compacted to a relative compaction of at least 95 percent. Excavations and Slopes The Federal Occupation Safety and Health Administration (OSHA) and the Washington Industrial Safety and Health Act (WISHA) provide soil classification in terms of temporary slope inclinations. Based on the soil conditions encountered at the test pit locations, the weathered native soils encountered in the upper approximately four feet of the test pit locations and where fill and/or groundwater seepage is exposed are classified as Type C by OSHAIWISHA. Temporary slopes over four feet in height in Type C soils must be sloped no steeper than 1.5H:1V (Horizontal:Vertlcal). Medium dense to dense native soils encountered below about four feet where no groundwater seepage is exposed would be classifl6d as Type B by OSHAIWISHA. Temporary slopes over four feet in height in Type B soils must be sloped no steeper than H:1V. The presence of perched groundwater may cause caving of the temporary slopes due to hydrostatic pressure. ESNW should observe site excavations to confirm the soil type and allowable slope inclination are appropriate for the soil exposed by the excavation. If the recommended temporary slope inclination cannot be achieved, temporary shoring may be necessary to support excavations. Permanent slopes should maintain a gradient of 2H:1V, or flatter, and should be planted with vegetation to enhance stability and to minimize erosion. A representative of ESNW should observe temporary and permanent slopes to confirm the slope inclinations are suitable for the exposed soil conditions, and to provide additional excavation and slope recommendations, as necessary. Foundations Based on the results of our study, the proposed buildings can be supported on conventional spread and continuous footings bearing on competent native soil or structural fill. Where loose or unsuitable soil conditions are observed at foundation subgrade elevations, compaction of the soils to the specifications of structural fill, or overexcavation and replacement with granular structural fill may be necessary. Provided the building will be supported as described above, the following parameters can be used for design of the new foundations: Earth Solutions tm. LLC The Conner Homes Group, LLC September 23,2013 • Allowable soil bearing capacity • Passive earth pressure • Coefficient of friction 3,000 psf 300 pcf (equivalent fluid) 0.40 ES-2995 Page 8 A one-third increase in the allowable soil bearing capacity can assumed for short-term wind and seismic loading conditions. With structural loading as expected, total settlement in the range of one inch is anticipated, with differential settlement of about one-half inch. The majority of the settlements should occur during construction, as dead loads are applied. Seismic Considerations The 2009 International Building Code specifies several soil profiles that are used as a basis for seismic design of structures. If the project will be permitted using the 2009 IBC, based on the soil conditions observed at the test sites, Site Class C, from table 1613.5.2, should be used for design. The 2012 IBC recognizes ASCE for seismic site class definitions. If the project will be permitted under the 2012 IBC, in accordance with Table 20.3-1 of ASCE, Minimum Design Loads for Buildings and Other Structures, Site Class C, should be used for design. In our opinion, liquefaction susceptibility at this site is low. The relative density of the site soils and the absence of a uniform, shallow groundwater table is the primary basis for this designation. Slab-On-Grade Floors Slab-on-grade floors should be supported on a firm and unyielding subgrade consisting· of competent native soil or at least 12 inches of structural fill. Unstable or yielding areas of the subgrade should be recompacted or overexcavated and replaced with suitable structural fill prior to construction of the slab. A capillary break conSisting of a minimum of four inches of free draining crushed rock or gravel should be placed below the slab. The free draining material should have a fines content of five percent or less (percent passing the #200 sieve, based on the minus three-quarters inch fraction). In areas where slab moisture is undesirable, installation of a vapor barrier below the slab should be considered. If used, the vapor barrier should consist of a material specifically designed to function as a vapor barrier and should be installed in accordance with the manufacturers specifications. Retaining Walls Retaining walls must be designed to resist earth pressures and applicable surcharge loads. The following parameters can be used for retaining wall design: earth SolutiOns NW. LLC The Conner Homes Group, LLC September 23,2013 • Active earth pressure (yielding condition) • At-rest earth pressure (restrained condition) • Traffic surcharge (passenger vehicles) • Passive earth pressure • Coefficient of friction • Seismic surcharge 'Where H equals the retained height 35 pet 55 pet ES-2995 Page 9 70 psf (rectangular distribution) 350 pet 0.40 6H* (active condition) 14H* (at rest condition) Additional surcharge loading from adjacent foundations, sloped backfill, or other loads should be included in the retaining wall design. Drainage should be provided behind retaining walls such that hydrostatic pressures do not develop. If drainage is not provided, hydrostatic pressures should be included in the wall design. Retaining walls should be backfilled with free draining material that extends along the height of the wall, and a distance of at least 18 inches behind the wall. The upper one foot of the wall backfill can consist of a less permeable soil, if desired. A perforated drain pipe should be placed along the base of the wall, and connected to an approved discharge location. A typical retaining wall drainage detail is provided on Plate 3. Drainage Groundwater seepage was observed at one test pit location at a depth of five feet below grade during our fieldwork (September 2013). Perched groundwater seepage should be expected in site or utility excavations. Temporary measures to control groundwater seepage and surface water runoff during construction will likely involve interceptor trenches and sumps, as necessary. In our opinion, perimeter footing drains should be installed at or below the invert of the building footings. A typical footing drain detail is provided on Plate 4 of this report. Utility Trench Backfill In our opinion, the soils observed at the test sites are generally suitable for support of utilities. In general, the soils observed at the test pit locations should be suitable for use as structural backfill in the utility trench excavations, provided the soil is at or near the optimum moisture content at the time of placement and compaction. Moisture conditioning of the soils may be necessary at some locations prior to use as structural fill. Utility trench backfill should be placed and compacted to the specifications of structural fill provided in this report, or to the applicable requirements of the city of Renton. Earth Solutions NW, llC The Conner Homes Group, LLC September 23, 2013 Pavement Sections ES-2995 Page 10 The performance of site pavements is largely related to the condition of the underlying subgrade. To ensure adequate pavement perfonnance, the subgrade should be in a finn and unyielding condition when subjected to proofrolling with a loaded dump truck. Structural fill in pavement areas should be compacted to the specifications detailed in the Site Preparation and Earthworl< section of this report. It is possible that soft, wet, or otherwise unsuitable subgrade areas may still exist after base grading activities. Areas containing unsuitable or yielding subgrade conditions may require remedial measures such as overexcavation and thicker crushed rock or structural fill sections prior to pavement. Cement treatment of the subgrade soil can also be considered for stabilizing pavement subgrade areas. For relatively lightly loaded pavements subjected to automobiles and occasional truck traffic, for preliminary design purposes, the following pavement sections can be considered: • Two inches of HMA placed over four inches of CRB, or; • Two inches of HMA placed over three inches of ATB. Heavier truck-traffic areas generally require thicker pavement sections depending on site usage, pavement life expectancy, and site traffic. For preliminary design purposes, the following pavement sections for heavy traffic areas can be considered: • Three inches of hot mix asphalt (HMA) placed over six inches of crushed rock base (CRB), or; • Three inches of HMA placed OVer four and one-half inches of asphalt treated base (ATB). The HMA, ATB and CRB materials should confonn to WSDOT specifications. LIMITATIONS The recommendations and conclusions provided in this geotechnical engineering study are professional opinions consistent with the level of care and skill that is typical of other members in the profession currently practicing under similar conditions in this area. A warranty is not expressed or implied. Variations in the soil and groundwater conditions observed at the test pit locations may exist, and may not become evident until construction. ESNW should reevaluate the conclusions in this geotechnical engineering study if variations are encountered. Additional Services ESNW should have an opportunity to review the final design with respect to the geotechnical recommendations provided in this report. ESNW should also be retained to provide testing and consultation services during construction. Earth Solutions MN. LLC .... ....!lm; Imt ~1 "It':' <- 11 Ii ~ ·r-lj"irr.. n Reference: King County, Washington Map 686 By The Thomas Guide Rand McNally 32nd Edition NOTE: This plate may contain areas of color. ESNW cannot be responsible for any subsequent misinterpretation of the information resulting from black & white reproductions of Ihis plate. Drwn. GLS Checked HTW , Solutions NWllC .Engmeermg Construction Monitoring Environmental SCiences Vicinity Map Panther Lake Subdivision Renton, Washington Date09/16/2013 Proj. No. Date Sept. 2013 Plate 2995 1 I TP-3 .-r TP~j_ _L TP-61 I TP-::;r- TP.o1j_ .t'",.' w:si- w vj w :l Z ew < ,.. C() 9 NORTH ~~ o 50 100 200 1°"100' - -~ ~ Scale in Feel LEGEND TP-1-f-Approximate Location of ESNW Test Pit, Proj. No. ES-2995. Sept. 2013 Subject Site Proposed Lot Number NOTE, Tha gr~phlCS sh(lWTl on thiS plsta 3ra not intandad for dasign putpOsas or praeisa seek> maasuramants, but only to Illustrate the appromate test locations rela~ve 10 the appro.ximata locations of 8XIStiflg a~d lor proposed site featurM. The information iIIustratad is largely based on data provided by Ih", ~Iient at the time of oor study, ESNW Gannol be responsible fOf subsequent design changss or interpretation of th", dala by others. NOTE: This pl.&le may contain are.&>; of cClior, ESNW ~annot be responsible lor any subsequent misinterpr",tation olth", information rw.rltir.g from blac;k & whikl reprooudions of this plata. C t: .Q t: ~·S .B a...._ C'I "c t: .0 ._ o ~.c ~(/)<I) rsd>~ o~> ~ ro . 6:::.§ ~ c tiEd> ~ffia:: "- NOTES: • Free Draining Backfill should consist of soil having less than 5 percent fines. Percent passing #4 should be 25 to 75 percent. • Sheet Drain may be feasible in lieu of Free Draining Backfill, per ESNW recommendations. • Drain Pipe should consist of perforated, rigid PVC Pipe surrounded with 1" Drain Rock. LEGEND: Free Draining Structural Backfill iii 1 inch Drain Rock 18" Min. Structural Fill Perforated Drain Pipe (Surround In Drain Rock) SCHEMATIC ONLY -NOT TO SCALE NOT A CONSTRUCTION DRAWING RETAINING WALL DRAINAGE DETAIL Panther Lake Subdivision Renton, Washington GLS Date No. 2995 I Ct1eclked HTW Date Sept. 201 Plate 3 NOTES: • Do NOT tie roof downspouts to Footing Drain. • Surface Seal to consist of Perforated (Surround 12" of less permeable, suitable soil. Slope away from building. LEGEND: Surface Seal; native sailor other low permeability material. 1" Drain Rock 2" (Min.) Drain Pipe 1" Rock) SCHEMATIC ONLY -NOT TO SCALE NOT A CONSTRUCTION DRAWING FOOTING DRAIN DETAIL Panther Lake Subdivision Renton, Washington Drwn. GLS Date09/16/2013 Proj. No. 2995 Checked HTW Date Sept. 2013 Plate 4 -I Appendix A Subsurface Exploration ES-2995 The subsurface conditions at the site were explored by excavating six test pits at the approximate locations illustrated on Plate 2 of this report. The test pit logs are provided in this Appendix. The subsurface explorations were completed in September 2013. The test pits were advanced to a maximum depth of 11.5 feet below existing grades. Logs of the test pits advanced by ESNW are presented in Appendix A. The final logs represent the interpretations of the field logs and the results of laboratory analyses. The stratification lines on the logs represent the approximate boundaries between soil types. In actuality, the transitions may be more gradual. Earth Solutions NIN, LLC JOB NO. E.S~ 2 ~~ S' CLIENT CO\('\()oa('"' 'r\OM~ O~"~\0l*'~<yt TEST PIT NO . . DATE 9./1~/13 BY HT'N I ELEVATION Y'" 2-TP-I CONTRACTOR N W E.. ""(..0< Vo.-\-\ (\ ~ SHEET' of \ I!! 1 .5 en SURFACE CONDITIONS 'Ro; ~ ~ i3ro.>M b\~~ " -8 oS! ::J tl NOTE: DEPTH OF TOPSOIL & SOD 1'2: (-Tl'SL ~~~!!.OJ~ !~-'~: ----------------------_______ --- 1--~1---+----1 .~'~ ___ h.--~.-~~=-~~--.~~~~~---~ \.5' 6.~ -SM _§.~_S..il'bt.~~~_~1!\:!~yt\.,J'j~cl'-\l~~~.., ____ _ 1--~1---+----1 2 -------------------------------------------- 1----1r--t----1 3 - -------------------------------------------- 1----1r--t----1 4 - --------------------------------------------1---+--+---1 s-- 50S' \U..O 6--"'L t"'>. -.k-6.-----of'--T-Sfl:r-~io~··---f5q~«---- ~.s' 15.0 "f-ML t::.'I91~t.~-E;'.;;,.~-<...--:.I.--511.'f .. :_-~·· .'" ---:ir;15i .;;---_ _~1t ______ ~ ____ ~ _________________________ _ J---+--+----I &-,- 8.5' IT .3 9't-~1-::5:-0'"'!"\\-I--------------- - - ----- ----- - - ---- ----------- ~ 1--------------------------------------------1----1r--t----1 0 - J---+--+----I ... ~ 1---+--1---1 2- - J---+--+----I 3' '- J---+---+----I 4-- 1--~1---+----1 5· c- I---+--~--l 6- H- r- 1----1----1----1 8-1- r- t----+--+---i 9+ o Test Pit terminated at 'C.S -------------------------------------------- -------------------------------------------- -------------------------------------------- t-------------------------------------------- t--------------------------------------------• t-------------------------------------------- t-------------------------------------------- 1-------------------------------------------- feet below existing grade. @§) Groundwater (table f seepage) encountered at feet during excavation. Earth Solutions NWLLC JOB NO. CS-'2.o.~S' CLIENT (OO(J«<" ~ \)t.~OPI"<"A..tt TEST PIT NO. DATE" /13 II?;, BvHTW 1 ELEVATION 4(00 TP-2. CONTRACTOR NW t..~c.o..vo..+\n 0. SHEET IOf' .JIG; 0..0 E E .5; III SURFACE CONDITIONS i'&i ~ -8 F ;eH ~~SS .. m" .,c -8 .! ::J 8 NOTE: DEPTH OF TOPSOIL & SOD \ '2. 8-1- I---+--t----I 9-1- I- 1--11---1---1 0 -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- ~~~_CUi~~~~----------------------- ~------------------------------------------- ~------------------------------------------- ~-------------------------------------------, 1+ \l~ Ho.b 2-f-+=~"""~-I--------------------------------------------- 1---+--/----1 3-- ~__+--+-__l 4-: 1---+--/----1 S--- I---+--t---f 6-- - 7"- - 1-----1---11----1 8 I-----+---f------i 9- ~------------------------------------------- r------------------------------------------- ~------------------------------------------ -------------------------------------------- --------------------------------------------• -------------------------------------------- -------------------------------------------- 01--------------------------------------------- Test Pit terminated at '\.5' feet below existing grade. @Groundwater(table/seepage)encountered at feet during excavation. Earth Solutions NWLlC JOB NO. E.~-2qq 5" CLIENT c.onne.(" \-\~ ~\opm~t TEST PIT NO. - DATE g/\3b'2.> BY I-lTW I ELEVATION 4YY TP·3 CONTRACTOR NW E ~ c.o.vo.t\n~ SHEET I of I ..9! 0.:5 Eo. "'''' .. " Vl 0" ~8 ( IiY ~1. 1 SM 1.'5' q:~ - 1---+--+---1 2-- - 1----1---11---1 3- ~. 11.'-1 4-- I------+-'--t---j - - 1---+-----1f---I 5- ~. - SURFACE CONDITIONS Li~'n+ 6nJ~ ,~" NOTE: DEPTH OF TOPSOIL & SOD '" t.Q~Q\.~;~~~~~ft5 ~tih-r ---,-ii'_")7 -~ ~-;.t -iJl--: -;-:::",-, -~~-----e-----~tc------------------------ I -------------------------------------------- ~~~y~~-~~~-------------------------- 1----1---11---1 I---+-_b_'-j-\'l_'--jb 1--\!.O\'\ ---------- - - ------------- ------ - - - - ---- ----- , ,------------------------------------------- 1---+--+---1 8-r- I---+--f---I 9- 1----11---11---1 0-- 1---+--+---1 1-- r- 1---+--+---1 2-r- I---t--I---l 3- 1---+--+---1 4-r- 1---+-_+----1 5-r- r- I------+--t---j 6-r- r- I----If--I--; 7 r- 1----11--1---1 8+ 1---+---+-----19- o Test Pit teminated at (Q r------------------------------------------- r------------------------------------------- -------------------------------------------- r------------------------------------------- r------------------------------------------- r------------------------------------------- r------------------------------------------- r------------------------------------------- r-------------------------------------------• r------------------------------------------- feet below existing grade. ® Groundwater (table f seepage) encountered at feet during excavation. Earth Solutions NWLLC JOB NO. E.S·19~ S" CLIENT (ofiOef" \-l.o~ ~~\optc\en-T TEST PIT NO. DATE o./I' ... /!"b BY I-\.W I ELEVATION 405 TP·Y CONTRACTOR N VJ E OX I:. c>va+\C\<3 SHEET lof\ .J!o; OJ t!! .!:; SURFACE CONDITIONS 0.:6 .~ ..c: I/) a..c u., Bro.~b\~ EE Eo. a-~8 :lI~ .. ., 0 -8Jl fl" .,.., E NOTE: DEPTH OF TOPSOIL & SOD C _~L .~,"-~P~Q\..~ ~JJ. ________________________________ 1 ML _erQ~.!'_ ~ .s.u...l: ..... HI!d;"l"~n...~ ... _~.!).i~~ ______ "2' 2--~_~D_~_~~ _____________________ \9:l - 3 -------------------------------------------- 4' 4-~~--Qli~~~~r~Olt------------------r:1.~ - 5--~~~~-~~~------------------------------ &- 7---------------------------------------------- --------------------------------------------- 8' I Lf."\ 8--~ .c. Ji~:t-~1l..~_V:~ D.eltl-!..rMai.s.t:. _________ 9---------------------------------------------- 0 SOH Ie:>' \'2. ::\ 1---------------------------------------------- --------------------------------------------2- 3-~ -------------------------------------------- 4-~ ~------------------------------------------- ~------------------------------------------- 5--------------------------------------------- 6- --------------------------------------------• 7-- --------------------------------------------- 8 - --------------------------------------------- 9-- 0--------------------------------------------- Test PH terrmnated at I 0 feet below existing grade. (NO) Groundwater (table ~pa~ encountered at S" feet during excavation. Earth Solutions NWu.c JOB NO. ESoo'lC\q,:) CLIENT (o'('\n~( \\o'('C'\e~ t'x.\IQ\OD~tlt TEST PIT NO. DATE o../\~/\~ BY HTW I ELEVATION '1 ccA TP-S CONTRACTOR NW E. ')( c.o.. voetiC"l ~ SHEET \ of I ..921; .!: SURFACE CONDITIONS .s::; !3cu r_ 0..<:1 EE .. ::I me: 0.1 U)"CI ~rG\s.s .. -8.!! ::J 8 NOTE: DEPTH OF TOPSOIL & SOD <0 1----+--+--1 1 C -g't ~9 P_S.9J~ _WI ~'-SrL "T T -:-.;;. -,fC-M..~: ;;.;::. -f ----'iii' -.-.,r - , 2-f-- '1.."5' \" ~ I---f---f----I 3 f-- 1----1---1----1 4- r------------------------------------------- 1-If nt.;# ........ ~-~;p .... -L-.------------------------J---+--t---I5-_ i-+:.::-':":'"""il-G"..,. -~ ... -s:;H·~-5KNn \"-+K"t! ---. r -~;l';",;;;'''' ----... -.-;;---:=:=(()=·:=9=.1: :f--SI'I'I f-_______ ~ ___________________________ ~ ______ _ ---------------------------------------------I---+-+-----i 8--- q' q.O ~ ~ -------------------------------------------- 0- I--+---If---j 1- - J---+--t---I 2-- 1----+--+--1 3-= J---+--t---i 4--= 1----+--+--1 5-~ 1- I---+--t---I 6-f-- f-- 7-f-- f-- I----If---If----I 8 f-- 1---+---+---1 9-f-- Of-- Test Pit tenninated at 9. -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- f-------------------------------------------- r-------------------------------------------• f-------------------------------------------- f-------------------------------------------- f-------------------------------------------- teet below existing grade. ® Groundwater (table I seepage) encountered at feat during excavation. Earth Solutions NWLLC JOB NO. E::,-'2.QQS CLIENT (onn~ \10t'l\eS Deve\o'Dl'oQo"t TEST PIT NO. DATE o../l'~kJ:J BY HTW I ELEVATION ,-\40 TP-6 CONTRACTOR NW E Xc.o.V ~+i<\<?J SHEET' on J!~ a.Jl EE .5 (fJ SURFACE CONDITIONS i -0 OJ 8f'01C'r'\'c\~s • <11::1 UJC -8 j ~ "8 NOTE: DEPTH OF TOPSOIL & SOD \ L 1--___ 1--___ 1----1 3 r- 1---+--+--1 4-r- 5' \'?l.C 5"r- 1---+--+---1 &+ r- 1---+--+---1 rr- r- 1---11---+----1 0+ t----+--t----l 1-r- r- t----+--t----l 2"r- I---+--t----I 3- I---+--t----I 4- 1---+---1--1 5- 1---1--1,----1 6 1---1--11----1 8-- - 1---+--+---1 9-- o Test PR terminated at 8 -------------------------------------------- -------------------------------------------- -------------------------------------------- r------------------------------------------- r------------------------------------------- r------------------------------------------- r------------------------------------------- --------------------------------------------• -------------------------------------------- -------------------------------------------- feet below exisHng grade. @ Groundwater (table I seepage) encountered at feet during excavation. Earth Solutions NWu.c Appendix B Laboratory Test Results ES-2995 Earth Solutions ~, LLC til Earth Solution. NW GRAIN SIZE DISTRIBUTION " • I . 1805 -138th Place N.E .• Su~e 201 Bellevue. WA 98005 Telephone: 425-284-3300 CUENT Conner Homes DeveloDmenl PROJECT HAlliE Panther Lake Subdivision PROJECT NUIIBER ES-2995 PROJECT LOCATION Ron!!!n u.s. SIEVE OPENING IN INCHES I U.S. SIEVE NUMBERS I HYDROMETER B .. 3 2 1.5 1 " 112 3 6 810141620 30 40 5060 100140200 100 I I :\'. -L , I 95 ~ \ 90 85 '\ -~ 80 ~ I; 75 "" ""-I~ 70 ,\\ 65 .... I~ :z: C!I 60 ~ \ ~ 55 II: 1\ w 50 \ ~ .... 45 z 1\ w l;! 40 w \ Il. 35 - 30 25 20 15 10 5 0 100 10 1 0.1 0.01 0.001 GRAIN SIZE IN MILLIMETERS I COBBLES : GRAVEL I SANO I SILT OR CLAY coarse I fine I coa .... I medium I fine I Specimen Identification Classification LL PL PI Cc Cu 0 TP·2 2.5ft. Brown Sandy SILT, ML til TP-4 1D.Dft. Gray Blue Sandy SILT, ML I; TP-5 6.Oft. Gray SRty SAND with Gravel, SM Specimen Identification 0100 060 030 010 %Gravel %Sand %Sitt %Clay 0 Tp·2 2.6ft. 19 0.086 2.8 39.7 57.8 til TP-4 10.Oft. 9.5 0.4 37.2 62.3 I; TP-5 6.Oft. 19 0.374 18.8 63.3 30.1 EMAIL ONLY REPORT DISTRIBUTION ES-2995 The Conner Homes Group, LLC 846 -1081h Avenue Northeast Bellevue, Washington 98004 Attention: Ms. Jieun Shon Earth SoluHons NW. UC APPENDIXC Critical Area Report for Panther Lake Sewall Wetland Consulting, Inc. Sewall Wetland Consulting. Inc. January 28,2014 Rob Risinger Conner Homes 846 108th Ave NE Bellevue, W A 98004 27611 Covingttm Way 5E #2 Covington WA 93042 RE: Critical Area Report & Supplemental Stream Study Panther Lake Plat City of Renton, Washington SWC Job #13-204 Dear Rob, Phone: 253·859·D515 Fax: 253-{l52-4J32 This report describes our observations of jurisdictional wetlands, streams and buffers on or within 200' of the proposed Panther Lake Plat (Parcels #3223059148,#273, #344,#123,#088,#080,#662340005~~cakdon the west side of 108th Avenue SE in in the City of Renton, Washington (the "site"). The site is an irregularly shaped 9.73 acre property containing five single family homes, as well as scattered outbuildings gravel driveways as well as large areas of lawn and ornamental landscaping. The site is located within the SE 'I. of Section 32, Township 23 North, Range 8 East of the W.M. METHODOLOGY Ed Sewall of Sewall Wetland Consulting, Inc. inspected the site on December 3,2013 and January 8, 2014. The site was reviewed using methodology described in the Washington State Wetlands Identification Manual (WADOE, March 1997). This is the methodology currently recognized by City of Renton and the State of Washington for wetland determinations and delineations. The site was also inspected using the methodology described in the Corps of Engineers Wetlands Delineation Manual (Environmental Laboratory, 1987), and the Western Mountains, Valleys and Coast region Supplement (Version 2.0) dated June 24, 2010, as required by the US Army Corps of Engineers. Soil colors were Panther Lake/#13-204 Sewall Wetland Consulting, Inc. January 28,2014 Page 2 identified using the 1990 Edited and Revised Edition of the Munsell Soil Color Charts (Kollmorgen Instruments Corp. 1990). The Washington State Wetlands Identification and Delineation Manual and the Corps of Engineers Wetlands Delineation Manual/Regional Supplement all require the use of the three-parameter approach in identifying and delineating wetlands. A wetland should support a predominance of hydrophytic vegetation, have hydric soils and display wetland hydrology. To be considered hydrophytic vegetation, over 50% of the dominant species in an area must have an indicator status of facultative (FAC), facultative wetland (FACW), or obligate wetland (OEL), according to the National List of Plant Species That Occur in Wetlands: Northwest (Region 9) (Reed, 1988). A hydric soil is "a soil that is saturated, flooded, or ponded long enough during the growing season to develop anaerobic conditions in the upper part". Anaerobic conditions are indicated in the field by soils with low chromas (2 or less), as Panther Lakc/!i13-204 Sewall Wetland Consulting. Inc. January 28.2014 Page 3 determined by using the Munsell Soil Color Charts; iron oxide mottles; hydrogen sulfide odor and other indicators. Generally, wetland hydrology is defined by inundation or saturation to the surface for a consecutive period of 12.5% or greater of the growing season. Areas that contain indicators of wetland hydrology between 5%-12.5% of the growing season mayor may not be wetlands depending upon other indicators. Field indicators include visual observation of soil inundation, saturation, oxidized rhizospheres, water marks on trees or other fixed objects, drift lines, etc. Under normal circumstances, indicators of all three parameters will be present in wetland areas OBSERVATIONS Existing Site Documentation. Prior to visiting the site, a review of several natural resource inventory maps was conducted. Resources reviewed included the National Wetland Inventory Map, the NRCS Soil Survey online mapping and Data, WDFW Priority Habitats mapping website, and the King County iMap website. King County iMap website According to the King County iMap website there is a Type F water (fish bearing stream) to the west of the site. This stream is known as Panther Creek. National Wetlands Inventory (NWII The NWI map depicts a stream to the west of the site classified as R3UB (riverine, upper perennial, unconsolidated bottom). Panther Lake/#13-204 Sewall Wetland Consulting, Inc. January 28,2014 Page 4 Above: King County iMap critical areas map depicting fish bearing stream west of site. , '" .( ' .. '-r'" • · • \ . \ ,m f'EMC. / • \ • (o\--PU6H~ \ ... Above: NWI Map of the study area p City of Renton Stream Inventory Panther Lake!#I3-204 Sewall Wetland Consulting, Inc. January 28, 2014 Page 5 The City of Renton Stream Inventory depicts a Class 2 stream (pink line) to the west of the site, and a Class 4 stream (Brown line) along the south edge of the site. City of Renton Stream Inventory Map Soil Survey According to the NRCS Soil Mapper website, the site is mapped as Alderwood soils between 6%-30% slopes. Alderwood soils are moderately well-drained soils formed under conifers in glacial till and are not considered a wetland or hydric soil. Panther Lakel#13-204 Sewall Wetland Consulting, Inc. January 28,2014 Page 6 Above: NRCS Soil map of the study area. WDFW Priority Habitats According to the WDFW Priority Habitats mapping website, the only priority habitat on or near the site is Panther Creek (purple line) to the west of the site. Panther Creek is depicted containing resident cutthroat trout as well as coho salmon. Above: WDFW Priority Habitats Map of the site. Field observations Uplands Panther Lake!#13-204 Sewall ¥/etland Consulting, Inc. January 28, 2014 Page 7 As previously described, the site contains several single family homes and outbuildings located along the east side of the site. These homes have associated gravel driveways, landscaped lawn areas, as well as small pasture areas on the west side of the homes. The site slopes from a high point on the east down to a low point on the west, which sits on the top of a steeply sloped ravine containing Panther Creek off-site to the west. The majority of this sloping area is abandoned pasture and lawn areas dominated by a mix of pasture grasses including orchard grass, tall fescue, bentgrass and quackgrass. Forested areas consisted of an immature deciduous forest canopy of red alder and big leaf maple with a dense understory of Himalayan blackberry, sword fern, indian plum, elderberry and stinging nettle. Soil pits excavated along the sloping upland area surrounding the wetlands revealed a gravelly loam with a soil color of IOYR 3/3 which was dry, Wetlands Wetland A Wetland A is a 7,744sf, slope-type, emergent wetland flagged with flags AI-All. This wetland is a disturbed wetland in an old pasture and appears to have disturbed soils from past plowing and grading, This wetland is dominated by a mix of reed canary grass, soft rush, creeping butter cup and blackberry. Soil pits excavated along the edge of the wetland revealed a dark (1 OYR 2/2) gravelly loam with common, medium, distinct redoximorphic concentrations. Soils were saturated at a depth of -9" during our site visit. It is unknown if these areas remain saturated within 12" of the surface during the growing season. Panther Lake/#13-204 Sewall Wetland Consulting. Inc. January 28, 2014 Page 8 Using the US Fish and Wildlife Wetland Classification Method (Cowardin et al. 1979), this has areas that would be classified asPEMIC, According to the criteria in City of Renton Municipal Code (RMC) Chapter 4-3-050,M.l, Wetland A would be best classified as Category 3 wetland. Category 3 wetlands are defined in Code as follows; iii. Category 3: Category 3 wetlands are wetlands which meet one or more of the following criteria: (a) Wetlands that are severely disturbed. Severely disturbed wetlands are wetlands which meet the following criteria: (1) Are characterized by hydrologic isolation, human-related hydrologic alterations such as diking, ditching, channelization and/or outlet modification; and (2) Have soils alterations such as the presence offill, soil removal and/or compaction of soils; and (3) May have altered vegetation. (b) Wetlands that are newly emerging. Newly emerging wetlands are: (1) Wetlands occurring on top offill materials; and (2) Characterized by emergent vegetation, low plant species richness and used minimally by wildlife. These wetlands are generally found in the areas such as :the Green River Valley and Black River Drainage Basin. (c) All other wetlands not classified as Category 1 or 2 such as smaller, high quality wetlands. Typically, Category 3 wetlands have a 25' buffer measured from the wetland edge. Wetlands B, C, D and E Wetlands B, C, D & E are emergent wetlands which are similar in character and appear to have evolved in disturbed soils and are dominated by low plant species richness consisting of invasive plants. Wetland B is 1,198sfin size and was flagged with flags BI-B6, Wetland C is 274sf in size and was flagged with flags C l-C5, Wetland D is 379sf in size and flagged with flags DI-D5, and wetland E is 996sfin size and was flagged with flags EI-E8. All of these wetlands are dominated by a mix of creeping butter cup and blackberry. Panther Lake/#13-204 Sewall \Vetland Consulting, Inc. January 28.2014 Page 9 Soil pits excavated within these wetland revealed a dark (10YR 2/2) gravelly loam with common, medium, distinct redoximorphic concentrations. Soils were saturated at a depths ranging from -2" to - 10"" during our site visit. It is unknown if these areas remain saturated within 12" of the surface during the growing season. Wetland E is highly altered and appears to be totally supported by artificial water sources including a roof drain from a home and garage, a gray water drain from the home and a drain tile from a previous water line construction just upslope of the wetland. Using the US Fish and Wildlife Wetland Classification Method (Cowardin et al. 1979), all of these wetlands would be classified asPEM1C. According to the criteria in City of Renton Municipal Code (RMC) Chapter 4-3-050.M.l, these wetlands would be best classified as Category 3 wetland. Category 3 wetlands are defined in Code as follows; iii. Category 3: Category 3 wetlands are wetlands which meet one or more ofthefollowing criteria: (a) Wetlands that are severely disturbed. Severely disturbed wetlands are wetlands which meet the following criteria: (1) Are characterized hy hydrologic isolation, human-related hydrologic alterations such as diking, ditching, channelization and/or outlet modification; and (2) Have soils alterations such as the presence offill, soil removal and/or compaction of soils; and (3) May have altered vegetation. (b) Wetlands that are newly emerging. Newly emerging wetlands are: (1) Wetlands occurring on top offill materials; and (2) Characterized hy emergent vegetation, low plant species richness and used minimal~v hy wildlife. These wetlands are generally found in the areas such as the Green River Valley and Black River Drainage Basin. (c) All other wetlands not classified as Category 1 or 2 such as smaller, high quality wetlands. Typically, Category 3 wetlands have a 25' buffer measured from the wetland edge. Streams Panther Lake!#13-204 Sewall Wetland Consulting, Inc. January 28,2014 Page 10 Panther Creek (orr-site) Anther Creek is located off-site to the west approximately 70'-130'. Panther creek is located in a steep sided ravine and is relatively undisturbed with good forested buffer areas. Panther Creek is classified as a Class 2 water on the City Inventory. ii. Class 2: Class 2 waters are perennial or intermittent salmonid-bearing waters which meet one or more of the following criteria: (a) Mapped on Figure Q4, Renton Water Class Map, as Class 2; andlor (b) Historically andlor currently known to support salmonids, including resident trout, at any stage in the species lifecycle: andlor (c) Is a water body (e.g., pond, lake) between one half (0.5) acre and twenty (20) acres in size. Class 2 waters typically have a 100' buffer measured from the ordinary high water mark. Stream A A small intermittent stream is located along the south side of the site. This stream is a narrow mud bottom channel that appears to carry primarily runoff from the streets to the eats of the site. This stream is classified as a Class 4 water in the City Stream Inventory. Per Code; iv. Class 4: Class 4 waters are non-salmonid-bearing intermittent waters during years of normal rainfall, and/or mapped on Figure Q4, Renton Water Class Map, as Class 4. Typically Class 4 waters have a 35' buffer measured from the Ordinary High Water Mark. State and Federally Listed Species Review During our review of the site, no state or federally listed species were observed on or near the site. A review of the Priority habitats mapping for the site revealed that there is no known use of the site by any state or federally listed species. Wetland Functions Panther Lake!#!3-204 Sewall Wetland Consulting. Inc. January 28. 2014 Page II All of the wetlands on the site are "slope type" wetlands, with varying degrees of disturbance. As slope wetlands, none of these wetland store or attenuate any runoff or flows, and in fact are areas where groundwater is perched or discharging on the surface of the ground before infiltrating on the lower edges of the wetlands. All of these wetlands are Category 4 wetlands using the WADOE wetland ratings system which scores the wetland on three main functions, water quality, hydrologic function and habitat functions. They score extremely low for water quality and hydrologic function and low for habitat function. None of these wetlands contain any of the complexities or unique features that are found in wetlands of moderate to high function and values. They essentially just meet the criteria of a wetland with little or no functional value. PROPOSED PROJECT The proposed project is the platting of the property into 34 single family residential lots with associated infrastructure. Due to the topography of the site, the stormwater facility must be located on the west side of the property and is proposed in the southwest corner. This will impact Wetlands B & C. We are also proposing to fill Wetland E which appears to hydrologically supported primarily by artificial water sources. This will result in a total of 2,468sf of Category 3 wetland fill. As compensation for this fill, we are proposing to restore and enhance 7 ,774sf of Wetland A which is a total enhancement/restoration ratio of 3.13:1. Per City of Renton Code 4-3-0S0.M.8; IfwetIand changes are proposed for a non-exempt activity, the applicant shall evaluate alternative methods of developing the property using the following criteria in this order and provide reasons why a less intrusive method of development is not feasible. In determining whether to grant Panther LakC/#13-204 Sewall Wetland Consulting, Inc. January 28,2014 Page 12 pennit approval per subsection M2 of this Section, General Standards for Pennit Approval, the Reviewing Official shall make a detennination as to whether the feasibility of less intrusive methods of development have been adequately evaluated and that less intrusive methods of development are not feasible: a. Avoid any disturbances to the wetland or buffer; The site contains three small wetlands which the developer proposes to fill and mitigate for through the enhancement of Wetland A. Due to the topography and the steep slopes, the only feasible location for the stormwater facility is on the southwest corner of the site which will impact Wetlands B & C. Wetland E appears artificially supported by various upslope drainage pipes and rains which will be cut off during the construction of the plat as well as extension of the sewer line from the north. Any development on the north side of the site to the east of this disturbed wetland will impact its hydrology so it is not likely to remain regardless of if it were impacted or not. b. Minimize any wetland or buffer impacts; To move the stormwater facility upslope to avoid Wetlands B & C would eliminate the ability to get storm water to the facility from almost half of the proposed lots. This would make the development of the plat not be financially feasible to construct. c. Restore any wetlands or buffer impacted or lost temporarily; and Restoration of this wetlands in this location would not be feasible due to the location of the impacts and configuration of the parcel and remaining wetland. d. Compensate for any pennanent wetland or buffer impacts by one of the following methods: i. Restoring a fonner wetland and provide buffers at a site once exhibiting wetland characteristics to compensate for wetlands lost; This is not applicable to this site as no historic wetlands are located on the property. Panther Lake/#J3-204 Sewall Wetland Consulting. Inc. ii. Creating new wetlands and buffers for those lost; and January 28,2014 Page 13 A total of 2,468sf sf of wetland will be filled. Due to the sloping character of the site creating wetlands is not feasible on this site. As a result, we are proposing using the "out of kind" provision in the Code using just wetland enhancement as mitigation for these small wetland impacts. Under 4-30-050.M.13, Out-of-kind replacement is allowed under the following circumstances 13. Out·oJ·Kind Replacement: Out-of-kind replacement may be used in place of in- kind compensation only where the applicant can demonstrate to the satisfaction of the Reuiewing Official that: a. The wetland system is already significantly degraded and out-of-kind replacement will result in a wetland with greater Junctional value; or The three small, slope type Category 3 wetlands are just small areas where topsoil was historically removed to expose areas where surficial groundwater is present near the surface. These small areas are covered with invasive species (creeping buttercup and english ivy). The functional value of these wetlands is extremely small, as previously described with essentially no hydrologic or water quality function and very low habitat function. One of these wetlands (Wetland E) appears totally supported by artificial water sources from a gray water drain, roof drains and drains that were placed when a water line was placed through the property years ago. b. Scientific problems such as exotic vegetation and changes in watershed hydrology make implementation of in-kind compensation impossible or unacceptable; or The fact that the site slopes with a gentle slope to the edge of a small ravine with steep slopes, and the fact the remaining wetlands are slope wetlands results in a site that does not work for creating wetlands which typically involves excavating out an area so it will hold enough water to create wetland conditions. To attempt to create wetlands at a top of a slope is not prudent as it could create a situation where soils become oversaturated and could cause a slope failure. c. Out·of-kind replacement will best meet identified regional goals (e.g., replacement of historically diminished wetland types). Panther Lake!#13-204 Sewall Wetland Consulting, Inc. January 2R, 2014 Page 14 The use of enhancement of Wetland A at a 3.13: 1 ratio (5.26: 1 if Wetland E is considered a man-made artificial wetland) will enhance an existing degraded low value wetland, and create an area with a forested and emergent plant community with enhanced functional value, primarily by raising its habitat function. The minimal stormwater storage and water quality functions of these wetlands will be replicated with the storm water system. The enhancing of Wetland A will provide an adequate functional lift (raising the WADOE Category from a IV wetland to a III wetland) through enhanced wildlife habitat function to adequately mitigate for the lost functions of these small low value wetlands to be filled, Stream Buffer Impacts The proposed stonnwater outfall will be directed to the west, off-site into the buffer of Panther Creek to allow natural runoff to continue to flow to the west. (RMC) Chapter 4-3-050.l.8b states that criteria needed for crossing of a stream or its buffer; I. Criteria for Administrative Approval of Utilities in Stream/Lake or Buffer: New utility lines and facilities may be permitted to cross water bodies in accordance with an approved supplemental stream/ lake study, if they comply with the following criteria: (a) Fish and wildlife habitat areas shall be avoided to the maximum extent possible; and The proposed impact is just in the buffer and is at aright angle to the stream channel and outside the OHWM of the stream. The pipe will be above ground and anchored and then will go underground for a short section before the outfall structure. An area of 10' on each side of the pipe has been identified as the potential construction zone and restoration of this area will occur within this area of potential temporary disturbance, A Hydraulic Project Approval (HPA) will be submitted to WDFW for this outfall and will follow the requirements ofWDFW. (b) The utility is designed consistent with one or more of the following methods: Panther Lake/rrl3-204 Sewall Wetland Consulting. Inc. January 28,2014 Page 15 (1) Installation shall be accomplished by boring beneath the scour depth and hyporheic zone of the water body and channel migration zone; or NA, no work in the stream or under the stream is proposed. (2) The utilities shall cross at an angle greater than sixty (60) degrees to the centerline of the channel in streams or perpendicular to the channel centerline; or NA, no crossing of the stream is proposed. The crossing of the buffer will be at nearly 90 degrees meeting this criteria, (3) Crossings shall be contained within the footprint of an existing road or utility crossing; and NA (c) New utility routes shall avoid paralleling the stream or following a down- valley course near the channel; and The new line avoids paralleling the stream or following a down-valley course as required. (d) The utility installation shall not increase or decrease the natural rate of shore migration or channel migration; and The construction method and restoration plan should restore the stream buffer to a condition that will not increase or decrease the natural rate of shore migration or channel migration, (e) Seasonal work windows are determined and made a condition of approval; and The work was conducted during the seasonal work window approved by WDFW for the stream crossing project. (f) Mitigation criteria of subsection L3c(ii) of this Section are met. A mitigation Plan meeting this criteria (" Wetland Mitigation Plan-Conner Panther Lake" prepared by Sewall Wetland Consulting, Inc. will be Panther Lake/#13-204 Sewall Wetland Consulting. Inc. January 28, 2014 Page 16 submitted to the City, The restored wetland, stream and buffer will be monitored 4 times in Year 1, and once a year for 5 years as required by Code, If you have any questions in regards to this report or need additional information, please feel free to contact me at (253) 859-0515 or at esewall@lsewallwc,com , Sincerely, Sewall Wetland Consulting, Inc. Ed Sewall Senior Wetlands Ecologist PWS #212 Attached: Wetland Delineation/Plat Map Wetland Rating Forms Wetland Data Sheets I Panther Lake!#13-204 Se\vall Wetland Consulting, Inc. REFERENCES January 28,2014 Page 17 Cowardin, L., V. Carter, F. Golet, and E. LaRoe. 1979. Classification of Wetlands and Deepwater Habitats of the United States. U.S. Fish and Wildlife Service, FWSjOBS-79-31, Washington, D. C. Environmental Laboratory. 1987. Corps of Engineers Wetlands Delineation Manual, Technical Report Y-87-1. U. S. Army Corps of Engineers Waterways Experiment Station, Vicksburg, Mississippi. Muller-Dombois, D. and H. Ellenberg. 1974. Aims and Methods of Vegetation Ecology. John Wiley & Sons, Inc. New York, New York. Munsell Color. 1988. Munsell Soil Color Charts. Kollmorgen Instruments Corp., Baltimore, Maryland. National Technical Committee for Hydric Soils. 1991. Hydric Soils of the United States. USDA Misc. Publ. No. 1491. Reed, P., Jr. 1988. National List of Plant Species that Occur in Wetlands: Northwest (Region 9). 1988. U. S. Fish and Wildlife Service, Inland Freshwater Ecology Section, st. Petersburg, Florida. Reed, P.B. Jr. 1993. 1993 Supplement to the list of plant species that occur in wetlands: Northwest (Region 9). USFWS supplement to BioI. Rpt. 88(26.9) May 1988. USDA NRCS & National Technical Committee for Hydric Soils, September 1995. Field Indicators of Hydric Soils in the United States -Version 2.1 City of Renton Municipal Code "'" rL .. ." .! '0,,-~ > , "-\ \ 'N 89·58'20" W 115.03 \, \ ,~ '" "'----------~,r N tsll-bts:lU « I ~. p i'ln' ' .. ' ~ /i ,~~ II>~ <:fIr:'1::: I ~\ ""- \~D ~ \ \ ~ ------~ \ \ \ ~, \ \ :/ I ,.i~~ \~5LE ~.~ , . . ...::. ,: YE JIAYI & CHI MAN 3223059080 279.65 r-- \ \ ~c ~ \ l \ \ ~ "-~,.;". \ \1' '" \ _ -00 \ t~~--\:.= --~--PARCEL G -\-~ ~- -g--s. \"" X ___ ~ _ J~' __ j¥18/18~ w\-\ \ \ I~\ Jf=~-~ \ \ ~' ~i~~N1 F~T~L~7~~s I ~ \ I .. ''''I!&J.m1· ~.,Ib",,1!qI \ \ \ \ \ j. '\1 I 'I .~;<:~_ .. ~<..-±-S 89'54'17" E 279. N 89·54'17" W'-:-:~. \ 67.35' ! ", \ I '.' ,:/ ".-,:.:.. l'2'CON'C~E 482.48 IE I "+--1- I I I I I I I '+- I ~ A ti~.vr ~ j' , ? I >2A"'{:'/ ,,:.:.:' I .0' <_ , I I "\ \ DENIPSTER JAdQUE A 8956500120 DECAJp LARRL 66j4000n r ~ ,-, B5 "d1!itl.('~24" h i , \ TEBROCK LESLIE M 8950300100 /' YE JIAYI & CHI MAN 322.3059080 A PORTION OF THE SE 1/4 OF SECTION 32, Twp. 23N .. Rge SE. KING CO .. WA I w (/) ~'+- J:/i to I o : I , , I 1--~ , , , I , , ... ~ , T , , I , , ~ , ~ , , I , I n SCALE; 1" ~ 40' ,.......-- 40' 20' 0 040' CONTOUR INTE:RVAL = 2' LEGEND --0----F(NCE. BOM~D ----0----FtNCE. CHAIN-liNK -CAS TELEPHONE. 3VRlED TELEPHONE. oJVnHEAD --,,--WATER -@-APPARi:NT "l,T PIT lOCAflONS ~ ';ANIT~R" 5EWEfl MANHOLE • 5TOR~ DRAIN CATCH OIAS'N @ STClR~ nRAlN ~ANHOl F RCOF DRAIN • GAS METER • GAS VALVE " ~LcLlHIC~L "'tilt' ,",' " PCWEfl POLE W!LiCHT ~ PCWER POLE '" lCl.EPHON{ POI Q FI~E HDRAN! HOS, [JIB ® WAfER ~A~HOL[ • WATER "'ETER W ijATER ,'''LVE 0 DECIDUOUS .. DOUGlAS FI~ Q CONlrER if> CclJ~T[R J1. HCLLY 0 IIAPLE '" Sf'flUC[ ~~ I KlJb &: lACK • SET PK NAIL I REvIS,ONS 11/"/l'" ~ ~I() Ii [' j wle z o z2 ~i~ z, ;::: ~:::- ~~.; CIl",!;: Z8~ O;;~ 0o. I (/) w ::'i: o I (! w z z o () J08 NO ~ ~l i ~!. Ii !l ~~ 33 I .~~ E f. ~ ~i ~ ~£ o ~ ; ~ 3: •• ~ i~ "0 ~~ o. z ~ ~ w ~ «!j,l ...1 0 E a:~ w S I~ f-Bi Z1.5 « 0.. z ~ w ~ " o ~ u ;~-O~.-~I) PP-02 ~~~C~D 9Y C~TE:: 'li"ilIOJ C~TE: 0, ~""IT PP-02 2 CF 11 S~EET': I I i 1 f J J 1If-----r-~ ~ I I i_gJ-i~' \ i j i!!i§~~J I I I glilll;l j I i liJ J I~h i I I I I} I I I I! i ~ n i i J ~i ! I I I Lig I i l~iHjll M I IfofUUJ'! I 11~e '}.1 II , : 'hillm , ~ I 11111II1 1\1 I -; i f ill I I i . -J ~ n I I li'IIIIIII'I'11 : 1~11~ldB~I!ll I ~ I I I I I I I I I I I 'IJ ;: i tl i I!' +I~~WJ!!J.· till! \j IIJnJI~ IIH t! l! t ~ I i J Ii I ht Iii ! J l l ~ ~ ~.~ i ~ ~ \ I I 1.1• .f .1111 11111 ~ 1111111111 II 111111 111111 11111111111' IIJ i tUIIIIIIIIIII~111111I11111111 i I , ! { f J J i 1 l 1! l I i L. L«. L ...... " L I~ I Wlidad a-or Il1Mlber WETLAND RATING FORM-WESTERN WASHINGTON VcnioD 2· UpdIW Jaly lOO6lo incn.e a;canoy and nprodaoibility __ --- UpdaecI Oct 1008 wifIIfM, MW WDFW deIiaitioaI for priority h.Ibitm N .... oCwetlancI(iCknown): ~1u..rJ B ~ C-n.teoClit."';ti..:J' -1'1 Ratcdby » ~,-,,,, TraincdbyEoology? Yes_No_ Dateoftrainill8 __ SEC: TWNSHP: RNGE: bSrrfRinAppendixD? Ycs_ No_ Mapol_unM: Flgu .. __ Eo_.I ... ~'l'ifff' SUMMARY OF RATING Categnry baled 08 FUNCI10NS JH'Ovided by wetl .. d 1_ ll_ 1lI_ IV_V_ Category I -S_ >-'70 Category II -Sea .. 51-69 Catesory m -Sea .. JO.SO Cater;torv IV -Sean: < 30 Soon: tor Water Quality Fundions Soort: for Hydrologic: Functions Score for Habitat Funetionl TarALKO~ Ibr FaDcdonJ Category b ...... on SPECIAL CHARACfERISllCS or",etlaad 1_ ll_ Does.at Apply_ ; Finlll Category (dooote tho "Idgbeot" ..... .,. -...... ) I J \I I NOOCI of 1be abow: WcCJ..d IlwtiDI Fora -....... tlalbiJtp --VWIiDo 1 To be wed wi1b.EcoIosY Pllbiicl:eioa (104....06..02,5 WcdaDd IIIIM or Gather ..J3 ...,. C- Does tile .. etIaad uait beial rated meet my ortlle criteria below? If you IDJWef YES to any of the questions below you will need to p~t the ~and lIOCOIding 10 the regulation. regarding the special chan.ctcristics found in the 'M:daoo "documentcxt" IDCIlDII the wdland is on the "documented" mearuJ the "M:tland is on the with State listed plllrtt species are SP3. Don 1M w~thmd flllil contGin tndmdua/s ifPrlorlly .3p«iu li.Ucd by k WDFW.for I1w 8M"? SP4. Doa ~ w~1IImd tmil ~ a local ngrrificanu in addilion 10 IISjiurctiom1 For ex:unplc~ the wetland has been identified in the Shoreline Mas1cr l'ro@ram.1hc: Critical Areas Ordina~ or in a local management plan as having special rignifiCIfICCI. To comolete the next oarl oftne data sheet wu wlU need fo determine the Hw!rogeomgrphlc Class oflhe weJ/",d being rated The hydrogeomorphic elueificetion JfOupi wetlanda into tho!Ic that function in similar WIlY'. This simpliflCS the questiom needed to answer how well the wetland t'uncti.ons. The Hydr08eomorphic Class of. wetland can be determined. using the key below. Soe p. 24 for moredetailcd instructions on clasIifYing wetlands. WedIn!lRatintFom-WCIIan W.hiaport 2 YWIioo. 2 UpdIted wida _ WDFW ~ Oct. :MOB AIIptlOO4 Wetlaad aDllfI (It' aumbor ~ Oas.lficatlon or Wetland u.ito in western Washington 1. A!'C~s in the: entire unit usually controlled by tides (i.e. except during floods)" ~ . YES -tbowetland cIuo;. Tidol FIt .. If yes, ilt-tM .salinity oflhc water during periods of annual low flow below 0,5 ppl (parts pol' thouoand)'/ YES -lreoh ...... Tidal FIllIp NO -Sal ....... Tidal _p (£I_e) Qyour wedOltd can be cl~ as a FrulrwtJter Tidal FWn8"! tIM tltej0rm8 for lliv«'iM wetlontb. Q II is SaltwrMr Ttdal Fringl/! U Is ,.akd a.J an EIlfuIrlIte wd/tmd Wetlands that were called cstumnc in the first and second editions ofthc: t'lting system arc called Silt Water Tidal Frinp in the Hydrogcomorpbic: Clusification. Estuarine wetlands were: categorized sepamtely in the earlier editions,. and this gcpanLtion is being kept in this revision. To maintBin conai.atcncy between editions,. the tmn "Estuarine" wetland is kept Ploase note, howner, that the chanacteristics that define c.tegory I and n ettuarinc: -. bave changed (_ p. ). 1. The mtirte watland unit is f)atand precipillltion is the only.ource (>90%) ofwatcrto it, !!Cund~ Iurface: .... ter runoff arc NOT 8OUI'QC8 of water to the unit (NO -go J!!j YES -The wetland. class is "ats If your wetland can be danified as" "'FIaa" wetland, use the form for DepreuloDal wetland •. 3. Does the entire wdIand unit meet bodt of tile following criteri • ., _The vept:atcd part of the wdland i. on the aboreI of. body of permanent open 'Water (without aay vq;etation on the surface) It (cut 20 ~ (8 hal in aizc~ ... _'" _At~ 30% oftbc open wat« area is doepor thao 6.6 ft (2 m)? ':~ YBS-The woIland clus is Lob-II1o", (Lacamiao Frt.p) 4. Docs the...'!rc wetland unit_t all ofebe follO'\\i11l critoria1 ---=--'Ilt€\WtIand is on a slope (.tIt¥ "an ~ ~ ,,_01), _-_"The water flowI through the 'M1land in one diRetion (unidirectional) and usually c:omos from tcepl. It may Bow subturfaoc:. as sbcctfIow, or in a swale widwut ~ ~~ tbowetland .. _ being Impouaded? NOm: s~ willer doa rtOI pond in Ihue 'YF ofwellands ucept occasionGlly in wry IIItDlI awl.rlttJllow ~sion.t or behind Itsmurtocb (depnMioru ... ruually <3ft diom. ... f!!!!I' ... " .. ~ . NO -go to 5 YIIE The wetland 01 ... t. SIoJ!! WdIaDcI RaIirt.. F_ -,.,.... wuJdastoa 3 Ymioa. 2 UpcbtaI with __ WDFW dafiDitioat Oct. 2008 ..... '2004 WIMlmd nIDICI or tl1IIIIba' B :!. Does the entim wetland unit meet aD ofthc following criteria? __ The unit is in II valley. or stream channel, where it gem inlDldatcd by overbank flooding from that strc&m or river The overbank flooding OQcurs at least once "very two years. NOTE: T1w riwriM amil can conl4in fkp~ssiom that aT, filled with 'Water wMn dre river iJ nolflooding, NO ~ go to 6 YES -The wetland class is IUveriae 6. Is the entire wdland. unit in a topographic dcpr1::ssion in which wat« ponds, or is saturated to the !lUrfaoe, at some time during the year. '[7qs rMatU thtJt ml}'OIldn, if'JWewnl, 18 highD' thanlhe mien'(#' oj'tM wetlmuJ.. NO -go to 7 YES -The: v;etl.and class is Deprealoalll 7. Is the entire wetlaod unit IooakId in a very flat area with no obvious doprcllion and no overbank flooding. The unit docs not pond surface water more than • few inches. The unit IeCIIlB to be maintained by high groundwater in the area. Tho wetland !'My be ditched. but bu no obvious natural oudet. NO -go to 8 YES -The wetland cia .. is DepressIoDal 8. Your wdIand unit I!ICOJIUI to be difficult to clasaify and probably contains several difl'erc:nt HGM oIucs_ For example, eeeps It Ihe hue of I slope may grade into. riverine floodplain, or a small &I:ream within a deprctsional wetland has a mnc ofOooding aJona its sides.. 00 BACK AND IDENTIFY WHICH OF TIlE HYDROLOOIC REGIMES DESCRIBED IN QUESTIONS 1-7 APPLY TO DIFFERENT AREAS IN TIlE UNIT (make. roup ._h to boIp yOll decide). U .. the following table to identify the appropriate class to IllIC for the rating system if you have several HOM eW1IC1 pmontwithin your "...,uand. NOTE: Usc this table only if the class that is RCDmmended in the teCOncS oolumn represents 10% or DlOI'e oflhc total aml of tile wetland unit being rated. lf1hc ami of tile clasalistcd in column 2 is Icea dian 10'1. ofthc unit;. classifY the wetland Ulins the: clan that represents more than 90% of the total amL If you arc unable still to determine whiclt ofdle above criteria apply to YOUt wetland. or if you have more than 2 HOM clauel within a wdland boundary. classify the wcrtIaod as ~IoD.l for the rating. wetland IWmg Form -w..ccm Wahiaatoa 4 wnioa 2 ~ 'IIiih DOW WDFW de:finitionI DeL 1001 _2004 w..tJaM. IIIrItO 01 IPIftIIMr 13 s s s I foot wrtlcallrop 'n ~for~ 100ft Slopedsl%-2%. Siopa is 2% -S% Slope is IIJ'flUlI' Ibm S% e S 1.3 ClJldcleriIltics of Ito wpWion in Ibe WC!Ilmd Itt aocl pollutants! ChocM tIM patrll ~ for 1M _n:nptton that but flu ". llePkltton I" drs wetlmtd Dttrue Yepfatl'OI'f' 1M4I11 yt'Al haN trofdM "';ng the ~I nu[QJX (> 75" CONr). and tutad nream rrot grazed Of' JftO'IIH and planu an Irlglwr than 6 twclta.. Deaac,. ancut. beIbaceous v.-tion > 90% ofthlll wetlmd.. p:Mb. .. 6 Dc:wJe. uncut. bsbacooo:s ~U11 ;:-112 of_ poiub -3 Den .. woodY.~;:-~ 0(" Den .. UDWt,. horbIcoou, v.etatioa: :> 1/'" of.nll; Does not moot In)' or1be Amv«YESi coming idto bt wedmd flit wwld odIIIIrwIJe roducxI wahIr quality m IbtImls,. lKce« If'OUDChw,ter cIowapdi«It from *e 'MIdmd_ Nate which of 1M following condmcms prtWIdt ". WtCrt:U of po/JMtants_ A fUIIt may htwe pothdantz cotm1t:gfrOlll ...-uaJ IOIIncI. btlt 411}' I. MJtU'ce WOIIld qIIQ/l/Y aI opporDmt.ty. -Onzinc in Ibe WlIdaDd «WitbiD 1500 -lJntrMted 1IOrm\lllds' didlarp to weftand -Tilted fields. JoainI. or arcbards witiD 150 &ct of we6aDd -RaidIIIn1W. urbIIIII .-cas. or IOtf eotneS .. withiD 150 ft ups. or wedaad c .......... v~ ",' ,--,j 5,"'$.e 10..., t~ c: " " ., ...... R.tiqFom-,.....,W_hiapm II veniou. 2 Updatot fth ncrw WOFW ~ Oct. _I ....... - C> multiplier WedInd MIlle or n.nba' 3- s s s Choou rite poIlftI dfJPf'opnatefor lite ducrlpltOl'f. rltat btntjlt t:ONiItiom til tM (It MIS of pImrt! IhoMld btl tluck ~gJr (n,u:rlly> 118m). or dtnw .nottgh, to remallf tIt'«I dMrittg IwfacefJowl} Den., uncut. ....... veptation coven :> 90% of1M ~ of1tte wetlmd. Dco8C, \InOId, ttpI veeetation > 1/2 maofwcdmd Dc:mo. un .. rtpl veplatiQft > 114 .. More tun II" of __ i. &JV.ed. moMd. tilled or wgetation is The ilOIlO MIIlIad bas 100ofiturw. YES point3 - 6 c;.~ III tho 'MIdmd in aluadscape position Mlere the reduction in water velocity it provides helps protoet ~ property and aquatic relIOUR:O& fiom flooding or excessive lftdIor cro.sive dOM'? Nat. wldch ofllr6 following cowJUlQJU apply. -Wetlmd basllUdiaoe I'UIIlOfI" Ihal drain. to a rivet ()I' sham that hu flooding problems -!lObo< ~NOtfIM-_-:-"'-'-~-of;:"--,,:::,,---:,,-,,,,-,--tJoI--;CWd-;;/oy-.-,,-,uvolr(e..g.werlandll auep ,/rat ($ Oft 1M Ccnnmetl .. waa-t RatIai F_ -wMenl WabiapJn 12 wnion 2 t.Jp4Ited 1IriIII ftC1I' WDFW cWiDitiom Od.. 2001 AD,.m2004 \ =- multiplier -----.! I W~nameCW" D.umber--E Cowartlhr). SIB thrultoldfor.ac" cUu1l11l Y, QlCNI or Iffore thtm JOU of the ar-a tf_rdt tl IImtJiW thall 2.5 QCNI. _bod -:-n";..,,.,., .-~~.,., (areas Here IIhruIJIiI bave>3O%cover) Fon!3ted (~~ trees haYO >30% ccrvw) !fIM Ilntt h<u afcwutfticion cJ.d: if The foreIted.clUII bas 3 outof" &tna(0Ul0PY. 1Ub-Ganopy,!hrubt. berbM::oooa. -IIlOSIIIgrouDd-covcf) that: each CIOWf 20% wilbin 1Iw fcRstod polnon Add tIw munb«' ofNptalWlt ~ru tJr.:n qruJlih· If)lOM haw: 4 struaureI 01' mare 3 ......... .-Map t:l CooIMrdIn .\t8geClIUOn ~ pcinh-04 --. points-I typel f:(" WtMr regt1Ml (hydroperlOtb) pNltllJl withllt tIM .,.,fiiand. TIttJ lI1DW' r.gtmtf. heu to CQI.IIrr more tJratt l~ afthc walond cr Y, acre to COItm: (IU tertfor .,,,""_ <1"_) __ ~dy fIoodccl 01' mwdated 4 or more typcI pRIIICIIt _Seumally.tloodecl or immdtCed 3 types IRSMt ~icmally flooded cr JnuadalOd 2 types pr'ClICIIlt -7.........s «tIy I.",. ....... = PermlftflDtly flo\lrUla Itream or river in. or IdjlCClOt to,. the vdlard __ seuoaaUy flowing stream in, or adjllCa1t to, the wedaDcI poinrs -3 points-. poDrt-I poinb-O lAUj'riItp wetI#tItd -2 points _-2 .. ,- RichNlu ofPlmt Snooiel at leur 10 ttl. (diffoPW1fl palCMJ 0/"'" MDfN 8pf1dU t:4I'I1» colJlbiMd to".. 1M It# tlnlhf'Jkl) TOil/: do not haPIe to ItfZIJN 1M ~. Do 1IDI jltClucU ElITtZ#JtI1I MIl/oil, rwd ~6. J1firpM iooNltr1jiJ, Conodtan Tlrlstk If you counted: > 19 species poinD'" 2 LJIt spec;', below tf)lQlj wam 10: .5 -19 species poiDtI'" I <5.~ poiDtI-O o c) W.tbDd Ratifta: Fonn. -_'_ W.uingIDD. 13 'Wniott 1 UpcIUd 1IriIh __ WDFW IWinitior. Od. 2008 Total for pqe __ _ .... WetIIDd II8tM or raamber ~ H 1.4. Jntcnpcnjoo ofbabjtm. _ J1 16) ~_ Dooido from the diagranu below MiclhGr iImnpenioo between Cowvdin 'VesetaCion oIaue.(detcribod in H 1.1), or !he cluscsllld UD"I ... todarots (c::an includoopen \VI.teror mudflats) is higb. medium. low, or none. ~C¢y([.@ ~ Low-I point ' Mod«atc"" 2 poiotl-' --~ / [ripuilll braided cbanndsJ Higb -J points- NOTE: If you have four (IE' more clana or Ibreo vcgor.tioa c1ancs and open wUer the rdiJls is alwaY! "high". u.. nwp'of CcMwdirtftp!td;!n cIns .. H I.S. $E!!!jj" "ab. FHtIn!; (flU p. 77) Chtct 1M ha/Htdlfoatura that an pN#1rt ilt the w.lond. TM ffUmMr of ch«:b II the numb«' of poittb YOIl fIIIt I1rto 1M NXt cm..1IIl'I. ./Lotp, _ woody dobri. ";lbm", _4 (>4OL dicn_ ... 6 ft long). _SIIDdiDa:.up (4iImcter att\e boHom > 4 inebtll) ill the wcdInd _lJnden:ut Hnb are prclCOt for It 1eest 6.6 ft(2m) aodIor overhaDgiftg vogetation extendl at lcut33 ft(I81) <M!Ir. meam (ordi1dt) in" or ooadpous wilD lheunit, far at lealt 33 ft (10m) _StIIb1c .tecp 'banks of fille materiallbat might be used by beaver {II' musknlt f« dcmI:inJ (>3Odesn:e 1Iope) ORap ofnKlCllt beaver activity are preecat (CW'lhnlb. ortrus dtat have not ~t trunttd grcy/bruw1r) _At leal'/. acre of 1hiII-1tfImmcd pc:niltcnt v-cgftdim ()I' woody bnlldu:ls IIn:I pmiClDt in ~ 1IW ~ ptII"IDIIlGDlIy or teUOIlIJly inuncJaIDd.. (R7WctIlra for egg-/aying by ampIrJbl.a1't6) _llIvaaivo plants Cin'CIf lass tbm lSo/. oflbc MItlm:I .... m each stntwD ofplanb NOTE; Thrt 20" naud I" eariJ.o prirrttrrgz c{tIw wtdIfUai Olt ~ 78 ,,, all _rror. o H 1. TOTAL Score ~ potential for providing habitat i I AddlhescOl"f1s/torn HI. 1. H1.2. Hl.3. Hl.4. HL5 t ____ J Comme ... wctl.ad 1Wia, FotIft -WCIIIonI Wadlinpn. 14 VOfIicnll tJp4Ud with new WDFW da6oitiom Oct. 2008 "" ........ :i :::r-_I'. I ~ ~ ~ ~ ~ . I 1 ~9 i ~ ~ .#.~~A~ N "~. o~ h Hit' Hili Ii iilii HI! H!j i' E ~i ~i-~ ~ ~ ~ I )'8 j "'J!osG .i tl 1f itlll ~ ! i Ii iiJi iii ~i ~ I t~ fl~f f f f i~~~ ~ ~ tIl ·t~·i· e . t ·~1~~ III ~ fe ~ •. ! 8i Iii o.s;,§ "I ~ 1.= ~ 1". 'S ..-~f if '11 J $ ~ 1 0 ) ~ I Ifill if~! Ih i ~t 11 I • I I tl~!~ li~~ 11 1181 I I,I~; !Sj 'jijii;li1j ; iii ..; I: ~II! I ~ i J~lf! ii~ ~ • ~~S.~ • ~l 1 !"~!III"~·f i ~ II 'Ill I I '!i~flttli o l!l~ tl!oj t i~~ 'j l.l~ is.:l°l"" f ~!~ ~gi,j. ,oil _~~I~lji i ~~1:1 l:J~I-!! iIi 11jllijll1 II! I II ~i!; ~ ~ 0 ~ ~,!;~ -~ . -I _0 -e -1 1 S ~11jl !Ilie ~~f~ ! s s -s -, ~~ l~tt§~1§~~1§1~~ 1~1!II!i o ~loj11 31f1 ::; ~ j ~:z:!.~l =~ I.) ;: N ;;J111 I I I I I I II I N = III =u . Wet&anllll&llM 01' IUImber D Wcll~41 """PlIO t'i: There are at least 3 oCbc:r Mttands within y;, mile, and dM ICOIlIloctions betwen them. arc relativeI.y uodisturbod (Iiafrt grazing betWIXIII 'WCClInds OK. .. is lake shore wi1b IKIDC bo.tiII.Bo but contIOC)tions ,bouId Nor be bilCCtCd by paved roM&, fin, field .. ® """"'_ pomb-no 'Mdlftd. is (.ake...ftioBC oa a lab with IiUlo di~ lind 1herc are 3 othor wetlands witbiD % mile poiIltl-S Tb«o are at least 3 other-wotlanda v.ilhia ~ mile., BUT tho otmlOCdoos betwcea 1ham Ire disturbed poinb -3 The \\dan4 ia: lAb-muJo oa a lab wUh cIisturbueo md there are 3 other Jato-fringe 'W'et1aDd wiilin % mile points -3 l'bare is at IcIut I WdlIDd widUn ~ milo. poiDlII -2 Then are DO wdInds wi1bino ~ mile. poin1II-0 Hl. Total. Scon for H.bltn PuaetloDll - Watland.RatiDJFClt!IIII-~WuhiaJlDn 17 ~ 2 UpcbIod wiIb IlCW WDFW dGIhUtiOftI oct. lOO8 Au .... _ e" WodaDc! name or_ba-3 CATEGORIZATION BASED ON SPECIAL CHARACTERISTICS Please 4etemrlne ifdte wetl4nd.-the _iIIuJ", dncrlbed below and circle the approprillte tI1ISWIUS and Category. Does the wetland unit meet the followins crifm'ia for Elrtuarinc wctlanda? -The dominant water ~me is tidal, -VoptaIcd, 0UId -With a alinity Jreater than 0,5 ppt. YES -00 to SC 1.1 NO SCI.lIs National E.nwy Environmental. or sc 1.2 Is the wcdand unit at least 1 acre in Iiz.e and meets at leuttwo of the roHawing three condition.? YES -Cafogory I NO -CatcSCltY n -~ wetland is rdatively WKlisturbed (hal no dikins. ditching., fillill8. cultivation,. grazing. and baa less than 10% cover ofnon-native: plant spccica. Ifthc non-native Sparlin4 spp. arc the only spcciCII that cava- IIlOIC than 10',-9 ofthc wetland, then thc: wetland should be given a dual ratina (IIII). The am< ofSpu1ina would be rated • Cates"'l' n ..tU1.1he relatively undistucbcd upper marsh with native species would be a Category 1. Do not,. bowevcr. exclude thc area ofSpartina in ddcrminins Ibc size thrcshol.d of tIeR:. -Atleast~ of tho landward edge ofthc wetland has a tOO ft buffer of shrub. forest. or un-grazc:d or ulHno~ ptsaIand. -The wetland has at least 2 of tile foUO\\'ina: features: tidal channels. depressions with opm water, or contisuous freshwater wdlanda. Wctlad.RaqFOtrb--.ta'n waabirtpla II wnioa 2 UpAIod nit IICW WDFW dafimtiom Od. '2008 ...... 2004 C.t I Cat I C.t II Dual rodD8 l1li WadaAd.1IIlM or JPnber A WETLAND RATING FORM-WESTERN WASHINGTON Venion 2 -1.JpcWod.hd.y 2OO(j to lncnIM accaracy and raprvdllcibility --. .... Updated Oct 2001 wiCh b 1IC'III' WDFW dcfiaiIio. b prio:iIy habitatII Name ohvedand. (if known): ~ t-1--l. A Date of tite ~sit Rated by Traiacd byEoology? Ycs_No_ Date of train ins- SEC: TWNSHP: RNGE: IsSlTlRinAppcndixD? YCI_ No_ Map of wretIand unit: FlguN __ estimated .Iza SUMMARY OF RATING CIIIegory bued Oil FUNcnO~ded by wellud 1_ n_ 1lI_ IV_ <+- l<-l C. --: ~ , ' ~~ .... -\. <l 1'1 t,. c.tcsorY I -Soore >~70 Cab:gmy n -S<>Ore S 1-69 Cab:gmy m -S<>Ore 3().SO c.tcRorv IV -Score < 30 Soore for Water Quality Functions SooRl for Hydrologic Functions ~ Cor Habitat Functiool TOTALxore rorJu.ndlom ~ _'rv I Category bued .D SPECIAL CIIARA9fERlSTICS of welled 1_ 11_ Does Dot Appl~_/_ Final Category <tboose .... • .......... "" ... .,. _ ...... ) ~ None of tile above Wc&ad RatiDa Form -..tan WIIhiapIa ........ -~ioa. 2 To be...! 'III'iIII Jko&oay MIir;ation G4-06-025 w ...... ....,"' ........ fo Does the wellud unit being rated meet uy of the criteria below? If you answer YES to any of the qUCItiom below you will need to protect the wetland aocording to the :regulations regarding the ,pecial characteristics found in the ~and. TlraleMd (7 Endanger_ tudmt113J'"ks? For the purpoeos of this filing system. "documented-means the wetland j, on the appropriate state databue. Note: wetlands with State lillN plant 8pcciCS arc SP3. Dou 1M wetland lllfit contain IndividMals ojPrlorUy 8JI«~sli3t«J by lite WDFW for lite 811*? SP4. Doa tire wetklnd...u h4w a loctJ $IpiftCtltl« in. Qddltion to iUfiurctiorl8? For eumple. the wetland has been identified in the Shoreline Master Protrtm. tile Critical Areas Ordinance. or in a local management plan as havinl special To co"",l.te tire "ext pmt ofthe dgra sheet wu win need to determine the Hydrqgeomomhlc 'lgss qflhe wdgnd being rgted The: hydrogeomorphio otassifieation pvupe wetlands into tho9(\: that function in similar ways. This simplifies the quemons needed 10 armtm' how well the watland ftmctions. The Hydrogeomorphil;: CIa. of a wetland can be dctctmined using the key below. Sec p. 24 for more dc:tailcd ir.tructions on classifyins wct1and!. wdbod R.atms Fom --wn Wahia.,. 2 VIIftioa 2 1.JpIbtcd with now WOFW dofiait:ioaI Cd. 2001 ....... 2004 W"'1IInMI or tIDIIIbcIr __ a ... ificatlon orWeII.nd Units in Western WuhiDgt .. 1. An: the W&b:r levels in the entire unit usually controlled by tjdea (i.o. except during floods)? NO -go to 2 VIS -the _and ..... i. TldoJ Fri".. Ifycs,. is the salinity of the water durill8 periods of annual low flow below 0.5 ppt (par1lI per tho.......!)? YI!S-...... bw ..... TldoJ Fr1"F NO -SoI"',"r Tldol Ftiqt (Estuar1no) If yotW 'WIIdand cmr be cl446ifi6d IU 0 F,.uJrwAler TLdtal Pring. tuM tIttJ .forrtu /Of' Riwrinft tflltltlands. Ifit u Sahwottlr Tidal Frin, it is rated 4f art EltuarlM 1UIland.. Wetlands that were celled estuarine in the fin:l and ICCOnd aditions of the raUna: system aft: called Sah Water Tidal Fringe in the Hydrogeomorphic Claseification. Estuarine wetland, were categorized scpuately in the earlier editions, and this separation is beinS kept in this revision. To maintain consistency bctweorI edilions. the term "'Estuarine" ~ is kept. PIoue note, however, that the characteristicI that define Category I and n estuarine weIIond. have cIwIsed (_ p, ). l. The eatire ~tland unit i. flat and precipitation i. the only source (>9Q04) of water to it QroundW'lltor and .urface 'WBtcr runoff are NOT lOuroeB of water to the unit. NO -ao to 3 YES -The wetland class is nata lfyour wetland can be ol_tied u a "Flats .. wetland., uae the form for DepreuIonal wot!ond., 3. Doea the entire wetland unit meet both ofthc: following oriteria? _The vegctl.ted part of the wetland is on Ute shores of II body of permanent open water (without: any vqetation on the surfIce) at least 20 acres (8 ha) in size;. _AtI .... 3O% o[1heopcn water .... is dcepcr1han 6,6 ft(2 m)? NO -go to 4 YI!S -Tho _and .1 ... is IAke-1rIqe (IAe-Ftiqt) 4. Docs the cotire wd1and unit lIleet.O ofthc following criteria? _The -nand i. an , oIopc (Mop< can be very "..mu.I). __ The wa:mr floWI through tho wetland in one direction (unidiRctional) aM WRJaIly comes from 1SCq)S. It may Oow subaurfaoc. as IheetfIow~ or in a SWIIIc without distinct banD. __ The water leaves the ~and wttbout beIDtJ: Impouaded? NOTE: S",/tJCtI WIIkr dou PkH poM In dtUtl type of wetlontb uctIpI occosionally in very...ul """.noR_ depr<UiOM a behind """"""'" (Mp"''''''''' ""' .....rty <3ft taam_rer _ leu thQlf lfoot _pl. NO -go to 5 YES -The wetland class ia Slope: Willi!..!. Ratint Form -wcQI:m w .. bPlgrao 3 wmoa 2 lJpiIMt widllIO'W WDFW ~ Cd. 2008 -- WcOand DUM .. aumbet 5. Does the entire wetland unit meet.U of'ltle following criteria? __ The: unit is in a valley, or stream channd, where it gets inlDldatcd by overbank flooding from that atn:am or river __ The overbank flooding occurs at leut once every two years. NOTE: ~ riwriIM tmit can comaln _pM&J1otu that lITe filkd with water 1fI~" the river u ""'floodm~ NO ~ go to 6 YES -The: wetland class is IUverioe 6. Is the entire W'I:ItIand unit in a topographic depression in which water ponds, or is saturated. to the mrface, at some time: durins the year. TIds 1Man8 thtzJ.tmy OII"tll, if J"Y",nt, is hIgher than the inIoicr of IJre lHlltmd NO -go to 7 VIS -Tho -nand cI ... i. Deprea ...... 7. Is the entire wetland unit located in a very flat area with no obvious dcpreaaion and no overoank flooding. The: unit does not pond surface water mort: dwI a few ilXlhea. The unit seems to be maintained by high groundwater in the area. The'Mtland may be ditched, but bu DO obvious naturaloudet. NO -go to 8 YIS -The wetland class islJreprelsloulll 8. Your wetland unit seems to be difi"tcult to classify and probably containlaevetw1 different HOM clues. For example, accp!i at the buc of a slope may grade into a rivaincl floodplain, or a small «ream within a dcprcnional 'Mtland bas a zone of Oooding along it. side •. 00 BACK AND IDENTIFY wmCHOf TIlE HYDROLOOIC REGIMES DESCRIBED IN QUESTIONS 1·7 APPLY TO DIFFERENT AREAS nl THE UNIT (make a rough sketch to bdp you decide). Use the follov.ing table to idc!dify tho appropriate class 10 usc for the rating 8ystem: if you have IICVeral HOM cluscs prascnt within your wetland NOTE: Usc this table only jf Ibc class that is recommended in the second column repn:9CDta 10% or more of the total area of the ~tIand unit betng rated. If the uea oftheoluslistc:d in cohlllUl. 2 i8le. than 10% offlx: unit;. classify the 'Wdland 1IIing the class that rqnsent3 more than 90% of the total an:&.. Slope + Riverine Riverine SlotJC + Depressional 'anal Slooo + Lako-Lake-fri Deprcnicma1 + Riverine along stream Vllitbin DeprmionaJ l)cpreseional + I...a.b:·1iinae '01111 SaltWater Tidal Fringe and any other class ofrrcshwatcr Treat u ESTIJARINE under wetland wetland. with 8pecial charact'eristics If you are unable atill to determine which of the above oriteria apply to your wetland, or if you have mo~ than 2 HOM clasacs within a \\'dIand boundary. classify the: wetland.a DeprulkHlai for the rating. WotlMdRatmgForm-'MItem WuhiJlttoft 4 wnioa 2 Updated 'llrithfttW WDFW ~ Oct. XI08 ...... 2004 w ..... Dl:meor__ A s s s s 810f»isl%or IeM (a 1" 11.-/raJ a I footwrtical drop I,. mw.tM/or.,..", 100ft horlztNrtaI JJsttmce) plinb" 3 Slopoisl%-2% ~-.2 Slope i.2%.· S% ~ Slope i. groIkI' iwI. 5% poinlJ .. 0 Cltoou Ins pol"" appropnate for 1M. ducriptiOlf. t1Jtll batfth 'M ~getatton In tIw "lHtlmtd iNMI wplQtiofl",."l)IQIII htntt6 troabM 6«1. tMlDlllllrfr;rc6 (> 7'" ctNfI1"), tlItd tI1JCId "'""" !'tOt srm" (K _d and pImrh Q1'fIIttg/w ,~. :om .. ImGUt,. hcdIecoou. vegetdan :.-90% aftho WIIItIaDd anII '- Den .. uaeut.~~011 > III of.. '" 3 DeaIO, woody. YegIItatioa > % of aroa pntl .. 2 DauB. um:ut,1Mrbcoous voptatiCG > 1/4 of.. poiab" I Does DOt meet my ofdle cri .... 1bave for vegetatioa S 2. Does CIte wetlaad oU have dte OIJPOrtualtv to improve w .... qullty? Answer YES ifyoo bow or beUve1hcrc Ire poIluImb in arouo4~ or surfllCCl water C<lmiq into !be wed.-d tfW would oIbenviIO reduce water quIli1y irlllnllmS. bikes or IJCIUftdWller cIowagradi.eat fium ilG wdlIInd. Nm ",'-ell qftIMfoilowl,.. c:oMitlmu ~ 1M 8OIfI'CU of poIIIItoms, A Mit MaJ.' hawr poI/Jdanl8 comjttgfi'otn WlWtlI 8OIoIrru, bIIt ""'" Ilngi. IOfIf'c. wowld qu/ifym ~lY. -Orazing in 1he "MIland or widUD 150ft -UDtroIIod stIJrm"Mtcr di5Cblrges to-Mdmd -Jilled fields,. .... or a-ebanb widriD 1 SO foct of wetlaad Y Resideatial. urbr.t area,. (Ir golf ccu.IIlre wiIbia I SO ft upd~ of wedmd Com ...... WetladIWiqFonn-" ... W~ 11 ...... -wniDIll Updaecl with .... WDFW ~ Oct. 2001 I'" '~''i.~) 0 I 0 I C, til "7 multiplier ....::z.... '\.. 1'-1 1'-1 WdImd_ornamber A r-..,+ S, CIrtxJN the po4tt11 appropriate for tits ducriptlmt tIKII (1Wm1 c( pIatrc Jto.Jd be lhJcl6lOflg/r (tuv4' > 1181,,), or dii1me QIOflgh, to relffOi" U«f JwtlJfl nu/<I« fIowl) I;::;=-? 0IIn1e, uncut. dPI vegdation CO¥a'II > 90% of 1be nil of the M1land. DeIlIe, uncut, ft&Id vegetation> 1/2 II"Ca of wodMd po;m.< 3 Dense.uncut,dPl~> 1/4 .. points .. I ~ More Ibm 114 of IRII ill JRZCd. mowed. tilled. cr ~ is C -'." S .. .. _"lout 0 I 0 ~ ; __ ~ __ i S S -t. Doee th!f wetland Ilaw .. oppottuaity to reclvce fIoodlDg.ad erosion? Is dle WO'IImd ill. ImdscapD poIitiou l'IItere die reductioo in .... _ \'elodty it provides helps protoc:I do'MI*-. property and ~ I"CIOQtCO$ ftom ftooding or excessive lDd/or amive .BOWl? Note whi(;h ofdwfo/lqw"W COlI'diItimu apply. -Wetland hu: surface nznoft'tIW chins to .. riVCl" or *CUIl .... t hu flooding "",Ioms -0Iber 1-:"' ~ NO ifth. trtqJor IOtII'CW ofw«., II C07ftrolWJ by a ruervo.ir (~g . ."etlmrd is Q uep that II Oft lite ew/IItrVtlm INk of a daM) YES multiE!!CI" ill:l NO multi2!* isl S TOTAL • Hydrologic _ .. Mulbply the ""' .. from S ) by S 4 At£i!lCOTf! to mhk on P. 1 I. I c,. Canna .... w~ RmPa: FonD -'In:dIIm WubinpM. 12 ...... -wnio!l 2 ~ wilh ___ WDFW cSofiDitiom; Od. lOOK WIltlaDd IYIIlCI or n_1t« A cIa"", (JUS61Il (124 Ufltwd by CowarrJur)-Stu t1w3ltoldfor each -.l!IcIass is y..ocre 01' mon than IOH ofdN ana iff41lltjssmalk, ,Iran 1.5 ac1"U. , • • b<d / ~IPIIDb =S<:rubIIhniJ (1fOU wbc:to IIhrubIiI ba\'e:>3O%wver) ./ _FontIted (areas Men troet haw:>3O% CO\'CII") I lfths IInit hal aputed elalS efwd ifi 'IbcI bested daa Iw 3 wt of S lItraia (caaopy. JUb..cmopy.1brubs. berbaceocll. -mosaI~) IIhat each caver 20% wi1hiD. the ftnsted. poJ)pI Atidthe munberof~Dtl6ITllCltlTfl' thalqfllllJfY. /fytJll /tm.re; ... IbuctUreI CIt more "lap d CC<Mu'dIrt ~,.... , ......... .- .H~ioda.n pWib""4 poinU -. 1 (1ryJrOfMrlO<b) prumrt willlm tJw v8liawi. TIN vat. ngim.htu to covm-mon than Ilmo/tM 'tHIiandor % ""'"' to ct:1fUII. (lMtcd{or d.n:rlpttOIU tf"1rydropmods) _Pcmmteody flooded or inunda1cd 4 or meR 'YP" preMIdf _Soumally fJoodod a-mun4atl:d 3 typOS preseat _kaa11yO ...... ",1_ 'types_ _----;7_ ... -~only 1 typo_ __ Pennancn1ly tkMina: Itream or river in, or lI4jtcell.t to, tho MIdand _ Seumally ftowiaa: Itream. m. or adjlOellt to, !he wetImd _-2 polo" -; pom -2 :=g- ttl the wdIaad that cover at least 10 oJ. (di/fo,.111 patcltu of tbe It1IfH qI«W can 0. tXIIfIbIJwd to mut 1M stu drruhold) Yow do niX have to name tIM 6p«tu. Do PlOt jrteluJ. Efl1"QIf(llf Mllfol~ Ned canarygra.t.r. (IIlrple 10000000fo. Conaditm Thlrtk ItyoucounMd: ;> 19 .pecie. points -2 Us, speciu bdow tf~ want to: S ~ 19 species ~ <:5lpooics ~ o o c) Total for pasc __ WCIdmII R.tins: Fond. -_tmI W~ 13 vcnion:z Updltod ....... WDPW de6nitionI 0eL 2008 _2004 ,...:r ;,.f.) l- C> 3 Wednd!IIIM or numbc:r A iDterlIpc:nim be4ween Cowudin. vegetatioo 1.1). or the CIUSIIIl ad unvogetatedareu (can include open water or blab. medium. low, or mme. ~~~ ca~~~ ~··:.~I:-t ..... .' ~ad«atc>.~, .. ..-. ~ / [riparian brw.idod dtmncb) NOTE: lfyou have ODdopeo_ . SneciallWJitd Fo.turet.: The IftUffbu of cfMcb l"M. murtber of ptJt7rtt J'I7'I pItlln10 tIY Nt1%t CON"".. , _I..arge. dovmed. woody debris within the weiland (>4iD. diamc_ mel 6 It Ioq). ...... .1'"""" __ Stmdiq; .. (dillDOlor It tile bottom:> -4 inches) in the wctltnd /,,",1 .of _UDdetcnt bank! Ire prcICIIlt for at loa ... 6.6 It (2m) and/or ovcrbIOJing wgatation extend!! at least 3.3 ft (1m) aver allroam (Ot ditch) in. or cont:iguoUl with: tile wti"t,. for at least 33 It (10m) __ Stable sap blllks of fmc mat«ia.l1IW migbt bo usad by bet ..... or muskrat fa" domrins (>3Odeareo dope:) OR sigut ofrecentboaver Ktivity are pnsent (Cj/t Ihn4bs or trf1;a that ~ nof yet fJU'1ISd grq/br'otm) __ At leut Y4 .we of tUa-stemmcd penilteaf ~on. or woody branc:hcl arc prcamt ia areas 1hat &R pcnnaneatlyor teaJOD&Ily inundated.(rtrwctNrufor .,.14y1"8 by amphtblaM) _ Invuivo pImtI cover leu than 25% oftbe WEItIaad IrOl ia eadJ.1InIUm of pianb; NOTE: 17M 20" JtQled In earlY J'rlnltfl/ll Q/"tIw IIUfnIUJl on DQSle 78 is an 111"1"0'. eomrn. ... Wedmd Rltial Form -wemm WIIhiqton 14 wnioa 2 l1pt.Io4 willi _ WDFW dlfiaitioftl Oot. 2008 AD",,""" M.k D 2. CJ 'Z--7 j'r W ..... M!lMlOI"DlIIIlbc __ H 1. DoeI the wedud olt bllft the opportaDity 10 provide habitat for many .pecht? H2.1Bld1'm (>np.'1I) ..... - CItooH the dtUrlptton t/tQt be" ~1fl6 c:ontJtlO1I oflniffor of-.mkw/ turU. TM hightm ~ng crtterlolr ,hdt applJu to IM.",et/QIJ b fa be IUed in 1M ratmg.. Sa tq:t lOT d6finitlDn of ".ttdI,hlrNti. .. -100 m (330ft) ofl'tlalMlyundill1llbod~ ..... rocky.-cas. OCopcrl Mter ;>95% of ei.roomfereaoc. No 1ICnKltUre!I.ro Voilbia 1M UDdilturbod pat ofbaflbr. (reltdvety UIlCli.sUbed .110 mcens oo-snziu& ItO Imcbcapillg, no daily bumGl ute) P ...... -5 -100m (330 ft)ofreidYfll),UDdiJ1urbod \IIOgdaI«I ueu, rocty uaa, oropea wa1I:Ir > :so% dtaurlf«Cllco. ......-. -SO 111 (170ft) of rebltivdy undisturbed. ~ anu. roclcy IRa, or opec WIIhIr >9~% --Polnb-4 -100 m (33Oft)ofNlatiwly1llldisMbed vepldedareu, rocky..-cu,. «open .... ;> 25% -. PoWa-3 -~ at (170ft) of reIatiYeI:y UIlIdistarbod wplail:d...", rocky .-eel, or opeD wafI:Ir foc ;> -......-. ......-. In ...... does not -1lIV" of .. crIkrIa.~ -N ....... _( ........... lni .. )<rbui ....... wi ... l>m(lOft)of-.......~.::> girwmfereDOC. light 10 mocbdo ...... or 1nm we OK. ~ -2 -No pawd areu or buildiagl wiIlio SUm of wetlmd tOr >50% circ:um:ll:nnoll. Usb! 10 moderate grwziag. cr lawns aro OK.. ...... -2 -Heavy I"liIl8 in batr«. ......-1 -Vcgda10d buft'en Ib'O <2m wide (6.6ft) foc age than 95% ofdle cimJmfrnnce (c.c. tined fieI .................. beokook...,., .... ofM!!'" PoInts-a. z.. -Buffer doeIllOt moel' my «tho cdteria UoYe. ..-a-I ...... _-- H 2.2 Cmjdon 'Ad C '(Rep. II) H 1.2.llsthe-wetImd pmof.~)'~1Dd UDbroka:I. YClpbl corridor (oitbor ripuilD or upllDd) dlat is at IcuII $0 It wide,. tuts. at (cut lO%oover I:I"sbrubt. furest or IUIi1I'O undisturblld prairie, 1hat 00IDICds 10 etlulriol,. adler 'WdImds 0(" IJDdisturbod uplaads'" Ire lit leal 2SO I«OS in ti7.e? (dIatt: .In rlpdrUln con1dt;Jr" '-"'tty rued grav.l roodt. pawd roadt, Gn ~ breab In tiM comb). YES-4 ...... (86toH2.J) NO -BO 10 H 2.2.2 H 2.2.2 Is 1M wetIaDd pIrt of. rclativGly uod.isturbod md bDbrokm wpII.lDd c:crricb" (1CIiIttcI: ripaian oruplaDd) dial ilatlcut'Oft wide,. bas at least.3O% WYa" of .... or fomt. *'" COIIJMKltJ to CIbIIriet, odter WdlaDdI Of UDdiJ1urbcd Uplaod& that In! at least 25 I.CI'OI ill size? OR a I..ab-6inp wadmd. if it docs DOl: bave an uDdislurbed ccnidor u in 111.411 qucstiOli fbuye? YES -2 pGIntI. (go to H 2.1) NO" H2.2.3 H 2.2.3 II the wc6mI: witbiD , lUi (Ikm) of. bnIc:kiab or salt wata CItUcy OR '. "within 3 mi or .... fioIdor punn(>40 1iInI) OR. ( .. .... _20_ (YES-' NO-O __ Total fm' page 3.-. w~ R.linf FonII -wcRcm WadIiItp;Ift 15 --. 2 l1Jtd*d wih IIIOW WDFW ~ Ck:t. lOOt: ....... - ("'(I- 2... ....J WetJm:l,..., ortnlmb. A H2.3N_(I'a4iacont~Dri.~llItedbV-WIlEYv(M'""'a4c~ ~.f'DFWpriDriIy""" .tAt ctHUIIla "'''''** dlqca be/tlMti, iN ,. PHS rqI41tf *P'et"""'r. rmtIbeY*'t1""") \VhidI oflhc folIowin& priority babitds.-e within 33Oft(100m} oflbe WGtlaftd unit1 NOTE: the «»m«:ti()fU do not lien. to btl. relaltwly ,,~tJU'bId. ~SI""': l'tIroormiXfld.andsofupcm .--thlnO.4ba(1 8iCI't1). ~vasItJ Alas and. ConIden: Arou ofbabitatthat _e ftllatively importaIIt 10 various spedos ofnmv. tim and wildlifo(fNl1 ducrlptloru #, WDFW PHS rqJOrr p. IJl). __ B~ Jblds: Variablc size pall::bes of grass and fOrbs OIllhallow lIOib (MIl' bedrock. __ 0Id-pvwth'MaCgn: foma; {OW-cmwgt Mft gfCrmrdr qmfJ SIIInds of at least 2 tree ~ lOnnia,a multi .... yered cmopy with oocuiooaI :AnIlt openia.~ wilb at least 20 'tRIcIIIb (1 treu'acre:) :> 81 em (32 ill) ti or> 200 ~ of lip. IMatpn:! fqgb) Siands with averapdilmdtnmaoding.53 ml (21 in) dbit;.CI'OM'I cover maybe less that 100'%; ctOMl COYer may be Jess u.t 100%;. doc:ay, ~ IlUIIlben of snags. .d quantity of large da«mod materill is pncnUy less daa Uaat found ill okI-croWlh; 80 -2OO)Un old \WIt of tho CacIde mISt. ~ whHt OR: Woodlmcls SImds ofpn 0Ik or OIkIQOIlit« uaociatioDa when opy coverap of1he oK component is imp:ncrt (foil ~ in WDFW PHS nponp. 158). _RIputm: 1'bI:: tRIa .dj.cent to IIqU8tie systMU: wifI. ftowing WId« 1bat contains elements of both ~c: and terreItrl.aI ecoaystemI which mutually influence eac:b o1h«. __ WeIbkIe Pnkin: Hcrbaccous. DOIl-forelted plant oomnuan:ities that CIa either take tic rc.m of. dry pmiric or • .mprUie(/iJlducrlptiolU in ItDFW PHS reportp. 16/). _ .... ream: The combiJIatioa of pbyJi~. biolopc.t. aud dlanical proocncs and conditions Ibat iDIeract to provide ftnK:tionIlJifo history RlquircmClllb fir inItMuD tim and wildlife .......... __ NeanbDn: ReImvely undisturbed neasboJe batrilUl. These include: Cou1a1 NcanbtR, OpeD Coat N~ and Putot Souad NMI'Ihore. (fo1l dncrlpIlOIfI qhabUah and 1M dq'imtiOll o{relativelyMndimuW ~ III WDFW repot1: pp. 167-169andgl<mary In ~A). _Cna: A nahnlly occurrIngcavity. rocns, ~ or symmofinra ...... , t1 pusagM under the CItIb in soils, rock. ice, or 0Ih« geological fonnarioII3111d is large enough to contain a -... _0IfIIa: Greakrhu 7.6 m (25 ft) hiah IQd occurring below SOOO ft. __ TO.: Komopuou ... caofrocA:.rubblenqiaa: ia:.wrage size 0.15 -10m (0.5 -6.5 1\). composed. ofbaalt. andeIite,. aadlor lIIdimeataryroc:k,. inclild.iq riPfIll' slidM. IIld mine ..n .... May be _"'" wi'" <lift. _SMp .... Lap: Trcc!J ala ccmidorocl..,. ifiley are dead CI' dying and cxhibil .ufficimt decaychll'aClcriJlicllo enable cavity ~on'wte by wildlife. Priai1y magi have .. diamckl"lfbr'olsthelalrtof:>'1 cm(20 in} in westan WaJlliAttm and are:>:2 m (6.5 ft) in height. Priorityloga...-e:> 30 Wl(12 in) in diamdw It the larg_end. and> 6 m(20 ft) ' .... If 1Wtt.nd h .. 3 .... 1IIOft priority babitm -.. ,..... lfMtland has 1 pricrity babi1Ea -3", IfWlldand has 1 priorilybabilat-J ..... NobabilUl'" 0 poiatJ }10k: All wgetaMtlwdands 4I'fI! by dfIjI"illon a pna.nty halntat hill tJn net tnch«kd In ,h/J /in. NNrbv tHtlotub are atldruJed i" QJlCJtit)rl H 2& WtllbDdRatiqFonn-'IPOIIcIm Wahinpn. 16 WOlin 2 UpUed 1riIh DeW WDFW ddinitimw Oct. 2008 _200, ,..,'" , Wetland I\IftlICI or ._her ~ l---I H 2.4 WetlUld I m"e'" (<:horu~ tM. tIM ~"n oftlw ~ aroutrd,I.",et1artd,har bu/fiu) (Io.p. ") nere are It Ieut 3 other wetlancli M1bi1l 'It mile. and flc COIlDOCtionl bI!twecn 1bem are relatiVGly \DIdi&turbed (light graziDg ~ ~ OK. u i.1ab more witb !IOmO oo.tmllo but «JllI1CdioIlJ should NOT be bilClOtod by paved road., fiU. field .. or ~1U:.. . .... ,_.... ~ Tho woUUld is lab-friftgo 011. alako wi1h little diJtwbaace md dun IftI ): 0Iber lake-ftiDge wedmds ~thin 'IS. mile points-S Th«o are It leut 3 odtcr WC1Imda wi1bin Ya mila, BUT tho (;(IDDeCti(IG1 betwom tMm arc w""""" --, The wotland ia l&b-tiinp on _lab wUh diaturbaooo and there am 3 odla' lBo-fringe wetland M1hiD % mik pointl-3 1'here i. at loat 1 wca.nd wiCbia % mHo. _-2 There 11'0 110 wodaads wi1biD '" milo. points-O 'S H2. TOTALScoro-opportuoityforprovidi,.baIri1at .-1'-- Add d, .. c~sftono HZ.l HZ.. H2.J. HH • _____ TOTAL for H 1 from page: 14 Total Score lor HabItat FluactIoDi add the points for H 1. H2 and record the reaulton Wetlmd Ratiq:FOIIII--'-W..t.iqtocl 17 wnioG 2 UpdIted wiIh DOW WDFW cWi:DitiooI O;t. 2001 o. I "" .... - C> ----- "t ') Of 7 -II, WdlIndUDlClorllUlllb« A- CATEGORIZATION BASEP ON spEOAL CHARACTERISTICS Pf_ tktennine if the wdbmd _the tJJtribuIG described below an4 drck the tlppropritrte answen ",,4 Category. Docs the wetland unit meet the following criteria for Estuarine wetland .. ? -The dominant water R'gjme is tidal. -V~ •• nd -With. ulinity I!""''"' than o.s ppt. YES -00 to SC 1.1 NO sc 1.1 Is the wetland unitVr'ithin a National Wildlife Refbge. NalionaJ Park,. National Estuary Reserve. Natural Area Preserve, Stale Park or Educational, Environmental, or Scientific Roaervc desi.,natecI under WAC 332~30-1S1? SC 1.2 Is die wedand unit at least 1 acrcin size and meets It least two oftbe following three conditions.7 YES -Category I NO -Clteaor)' n -The wetland i. relativoly undisturbed (has no diking. ditching. fillma. w1tivation. srazins. and has lellS than 1m'. cover of non-native plant 1pCCiCl. lethe non-native SpartimI spp. arc the only species that cover more than 10% ofthc wetland. then Use wct1and should be gil'm a dual ratiOS (lID). The Il'eI. ofSpartina"MHlld be: rated a Category D while the relatively undisturbed upper marsh witb native specie! would be a Category L Do no~ however. exclude the area oC SpartiDa in dctonninins the size threshold of 1 8CR:. -At least s;" oftha landward edge of tile WCldancl has I 100 ft buffer of Ihrub, fCRII. or \Ul-graz.ed or un-mo~ srusland. -The wetland has at least 2 of~ following Ccaturcs: tidal channols. dcprasiOM with opal water, or conti8uoUl freshwl!er wetlands. Wcdud IWin.I Form -WfRm WaUtinpla 18 "...... 2 1JpdDd with .. WDFW defudtlODI Oct. 1»08 .... ,..,2004 Cot I Cat I CallI Duo! ndug l1li APPENDIXD Contech Stormfilter Sizing Sheets C'I~NTECH' ENGINEERED SOLUTIONS Size and Cost Estimate Prepared by Chris Hass on January 28, 2014 Panther Lake -Stormwater Treatment System Renton, WA Information provided: • Structure ID = • Total Area = • Water Quality Flow, WQF = • Peak Flow, Q100 = Bypass 0.16 0.04 0.21 • Presiding agency = City of Renton Assumptions: • Media = ZPG cartridges Combined 4.32 0.48 2.85 • Drop required from inlet to outlet = 2.3' minimum Size and cost estimates: The StormFilter is a flow-based system, and is therefore sized by calculating the peak water quality flow rate associated with the design storm. The water quality flow rate was calculated by the consulting engineer using KCRTS and was provided to Contech Engineered Solutions LLC for the purposes of developing this estimate. Structure Water Approximate No. of System Estimated Quality ID Flow Depth Cartridges Size Cost Bypass 0.04 8 3 48" MH $16,065 Combined 0.21 8 29 8x14 $58,800 This estimate assumes that the vault is 8 feet deep. The final system cost will depend on the actual depth of the units and whether extras like doors rather than castings are specified. The contractor is responsible for setting the StormFilter and all external plumbing. The Manhole StormFilter has an internal bypass capacity of 1.8 cfs. If the peak discharge off the site is expected to exceed that rate, we recommend placing a high-flow bypass upstream of the StormFilter system. Contech Engineered Solutions could provide our high-flow bypass, the StormGate, which provides a combination weir-orifice control structure to limit the flow to the StormFilter, for approximately $4,500. The final cost would depend on the actual depth and size of the unit. @2012 Contech Engineered Solutions T J ,C \n\\\-,( :olltcchl~~.c( )111 11835 NE Glenn Widing Dr., Portland OR 97220 TolI·free: 800.548.4667 Fax: 800.561.1271 Page 1 of 1 TS·P037 C(~NTECH' ENGINEERED SOLUTIONS CONTECH Stormwater Solutions Inc. Engineer: Date Site Information Project Name Project State Project Location Basin ID Drainage Area, Ad Impervious Area, Ai Pervious Area, Ap % Impervious Runoff CoeffiCient, Rc Water quality flow Peak storm flow Filter System Filtration brand Cartridge height Specific Flow Rate Flow rate per cartridge SUMMARY INumber of Cartridges ©2006 CONTECH Stormwater Solutions contechstormwater.com Determining Number of Cartridges for Flow Based Systems CRH 1/28/2014 Panther Lake Washington Renton Bypass 0.16 ac 0.16 ac 0.00 100% 0.95 0.04 cfs 0.21 cfs StormFilter 18 in 1.00 gpmlW 7.5 gpm 1 of 1 C~'>NTECH' ENGINEERED SOLUTIONS CONTECH Stormwater Solutions Inc. Engineer: Date Site Information Project Name Project State Project Location Basin ID Drainage Area, Ad Impervious Area, Ai Pervious Area, Ap % Impervious Runoff Coefficient, Rc Water quality flow Peak storm flow Filter System Filtration brand Cartridge height Specific Flow Rate Flow rate per cartridge SUMMARY !Number of Cartridges ©2006 CONTECH Stormwater Solutions contechstormwater.com Determining Number of Cartridges for Flow Based Systems CRH 1/28/2014 Panther Lake Washington Renton Combined 4.32 ac 4.32 ac 0,00 100% 0,95 0.48 cfs 2.85 cfs StormFilter 18 in 1.00 gpmlft" 7,5 gpm 1 of 1 Earth Solutions NWLLC Geotechnical Engineering Geology Environmental Scientists Construction Monitoring 1805 , , . . , GEOTECHNICAL ENGINEERING STUDY PROPOSED PANTHER LAKE RESIDENTIAL SUBDIVISION 18647 - 1 OBTH AVENUE SOUTHEAST RENTON, WASHINGTON ES-2995 PREPARED FOR The Conner Homes Group, LLC September 23, 2013 lt4~. Staff Engineer Kyle R. Campbell, P.E. Principal GEOTECHNICAL ENGINEERING STUDY PROPOSED PANTHER LAKE RESIDENTIAL SUBDIVISION 18647 -108TH AVENUE SOUTHEAST RENTON, WASHINGTON ES-2995 Earth Solutions NW, LLC 1805 _136TH Place Northeast, Bellevue, Washington 98005 Ph: 425-284-3300 Fax: 425-449-4711 1-866-336-8710 Impo~tantlnfo~mation About You~ Geotechnical Report SIJi1Sl)rl3v't l)l(}tJlt;,n~ are d {hint'!!),}! f'd:i'-;(-l (ll (It/sir ;r,!,(i," rirJ/f1~!0 L hI I \,c'/ur\:::., C/'-,II77-.., dfl(j j,,)[),/f[l'l • Til; fV//]~fl'il(j {,dO/:TI(1!,(' I i::'! Ie ',i',~,\;Cj tc~ "J,l/f, Y IU rOt" l~lc ~ r~ur ,lSI{::; GlIOtechnlc.1 Slrv1ca8 Are Performed for SpecIftc PurDtIIe8, Perl_, and Projects Geotecf1nical engineers structure their services to meet the specific needs of their clients. A geotechnical engineering study conducted for a civil engi- neer may not fulfi II the needs of a construction contractor or even another civil engineer. Because each geotechnlcal6llgineering study is unique, each gectechnical engineering report is unique, prepared solelyfor the client. No one except you should rely on your geotechnical engineering report without first conferring with the geotechnical6llgineer who prepared it. And no 000 -not even you -should apply the report for any purpose or project exoept the one originally cortenl>laled. R8III ... fill ReJII'I Serious problems have oocurred because those relying on a geotechnical engineering report did not read it ali. Do not rely on an executive summary. Do not read selected elements only. A GlltlclllKIIl$ _=Flls BII8II8I A Unique let.. ,. n Factor. Georechnical engineers consider a number of unique, project-specific fac- tors when establishing the scope of a study. Typical factors include: the client's goals, objectives, and risk management preferences; the general nature of the sbucture involved, its size, and configuration; the location of the structure on the site; and other planned or existing sire improverrents, such as access roads, parking lots, and underground utilities. Unless the geotechnical engineer who conducted the study specffically indicates oth- erwise, do not rely on a geotechnical engineeling report that was: • not prepared for you, • not prepared for your project, • not prepared for the specific sire explored, or • completed before important project changes were made. Typical changes that can erode the reliability 01 an existing geotechnical engineering report include those that affect: • the function of the proposed structure, as when it's changed from a parking garage to an office building, or from a light industrial plant to a refrigerated warehouse, • elevation. configuration, location, ori6lltation, or weight of the proposed structure, • compOSition of the design team, or • project ownership. As a g6lleral rule, always inform your geotechnical engineer of project changBS-ilVen minor ones---und request an assessment of their impact Geotechnical engineers cannot accept responsibility or liability for problems that OCCl.Jr because their reports do not consider developments of which they were not informed. .......... CoIdIIIDu can CIIIIIge A geotechnical6llgineering report is based on conditions that existed at the time the st\Jdy was performed. Do not rely on a geotechnical engineer- ing report whose adequacy may haw been affected by: the passage of time; by man-made events, such as constrUction on or adjacent to the site; or by natural ewnts, such as floods, earthquakes, or groundwater fluctua- tions. Alltayscontact the geotechnical engineer before applying the report to determine if it is still reliable. A minor amount of additional testing or analysis could prevent major problems. Most GIIt8I:hnIcII FIndiIp APe PI'II88IIIInII 111*" Site exploration identifies subsurface conditions only at those points where subsurfall3lllsts are conducted or samples are taken. Geotecf1nlcal engi- neers review field and laboratory data and then apply their professional judgment to render an opinion about subsurface condlions throughout the site. Actual subsurface condttions may differ~me!imes significantly- from those indicaled in your report. Retaining the geotechnical engineer who developed your report to provide construclion observation is the mostefiective method of managing the risks associaled with unanticipated COIIditions. A Repurt'l Rec:o:IHiitillllalllll. Are It1I final Do not owrrely on the construction recommendations included in your report. Those recommendations are not final, because geotechnical engi- neers develop them principally from judgment iII1d opinion. Geotechnical engineers can finalize their recommendations only by observing aclual subsuIface conditions revealed during construction. The geotechnical engineer who developed your repoFI cannot assume responsibility Dr liability for !he f8{Jort's recommendations if that engineer rloes no! perform COfIStrudion observation. A Geotechnical Engine ..... Report Is Subject to M1lnt8rpretatlon Other design team members' misinterpretation of geotechnical engineering reports has resulted in cost~ problems. LOIWr that risk by having your ge0- technical engineer confer with appropriate members of the design team after sUbmitting the report. Also relain your geotechnical engineer to review perti- nent elements of the design team's plans and specnications. Contractors can also misinterpret a geotechnical engineering report Reduce that risk by having your geotechnical engineer participate in prebid and preconstruction conterences, and by providing construction observation. Do Not Redraw till Engner's Logs Geotechnical engineers prepare final boring and testing logs based upon their interpretation of field logs and laboratory data. To prevent errors or omissions, the logs included in a geotechnical engineering report should nel'!1rbe redrawn for inclllSion In architectural or other design drawings. Only photographic or electronic reproduction is acceptable. but recognize that separating logs from Ure fIi{JOrt can efevate risk. GIve CUntractol's a Complete Report and GuIdIIIc8 Some owners and design professionals mistakenly believe they can make contractors liable for unanticipated subsuIface conditions by limiting v.f1at they provide for bid preparation. To help prevent costly problems, give con- tractors the complete geotechnical engi neering report. butprelace n with a clearly written letter of transmittal. In that letter, advise contractors that the report was not prepared for purposes of bid development and that the report's accuracy is limited; encourage them to confer with the geotechnical engineer who prepared the report (a modest fee may be required) and/or to conduct additional studY to obtain the specific types of information they need or prefer. A prebid conference can also be valuable. Be SUIIi conlnlc- tors hal'!1 sufficient time to peIfonn additional study. Only then might you be in a position to give contractors the best infonnation available to you, while requiring them to at least share some of the financial responsibilities stemming from unanticipated conditions. Raad ReIPlJllllblltY ..... vIsIuIlS Closely Some clients, design professionals, and contractors do not recognize that geotechnical engineering is far less exact tIian other engineering disci- plines. This lack of understanding has created unrealistic expectations that have led 10 disappointments, claims, and disputes. To help reduce the risk of such outcomes. geotechnical engineers commonly include a vari~ of explanatory provisions in their reports. Sometimes labeled "limitations' many of these provisions indicate where geotechnical engineers' responsi- bilities begin and end, to help others recognize their own responsibilities and riSks. Rear! these provisions closely. Ask questions. Your geotechnical engineer should respond fully and frankly. GeoenvII'IIIIIIIIIItII ConCll'lS AI'e Not Caverad The equipmenL techniques. and personnel used to peIform a geoenviroo- merrtal study differ significantly from those used to pertorm a geotechnical study. For that reason, a geotechnical engineering report does not usually relate any geoenvironmental findings. conclusions, or recommendations; e.g., about the likelihood of encountering underground storage tanks or regulated contaminants. UnanlicipaterJ errvironmental problems hal'!1 led to numerous project tailures. If you have not yet obtained your own geoen- vironmental information. ask your geotechnical consultant for risk man- agement guidance. Do not rely on an environmental report prepared for someone else. 0btaiJ PI'OflISIIanaI Assisb1nc8 Ta 0881 with MaId Diverse strategies can be applied during building design. construction, operation, and maintenance to prevent significant amounts of mold from growing on indoor surfaces. To be effective, all such strategies sliould be devised for the express purpose of mold prevention. integrated into a com- pret1ensive plan, and executed with diligent oversight by a professional mold prevention consultant. Because just a small amount of water or moisture can lead to the development of severe mold Infestations. a num- ber of mold prevention strategies focus on keeping building surfaces dry. While groundwater, water infiltration. and similar issues may have been addressed as part of the geotechnical engineering study whose findings are conveyed ilrthis report, the geotechnical engineer in charge of this project is not a mold prevention consultant none of the SlIrvit:8s per- fonned In connlll:UOII wItfI/he lIeol8t:lrnJt:81 '1IfIIn,,,,'s IdIItIy WIHII desillned or conducted for IhII fNJIIJlISfI 01 mold preVllll- lion. PfD/IIf Implllmflf1l1lfioo of /h8 IIICOmmtmdations t:fIIWIIysd In /his report will not of fIsIIU btl rufflelent tr1 preve"t mold from growi"'II" or on /h, IIfrIH:IuIf lIM/hied. ReII. III Yaur ASfE-MInDIr Geltei:ta:1II . ~ I ... AdiI ... AnIIbIICB Membership in ASFEfTIle Best People on Earth exposes geotechnical engineers to a wide array of risk management techniques that can be of genuine beneftt for everyone involved wnh a construction project. Confer with you ASfE-mernber geotechnical engineer for more infonnation. TU .n. P.".I II lUll 8811 Colesville Road/Suite G106, Silver Spring. MD 20910 Telephone: 301/565-2733 Facsimile: 301/589·2017 e-mail: Info@asfe.org www.asfe.org Copyright 2004 by ASFE. Inc. DupIJcat/on. mproduct/on. or copy/flg 01 ibis doctnrI.m, Ifl_ or Ifl /IIIrt by any mtIIIIIS II'INItsao .... ts _ ._. -' wfIh ASFE~ >P«I/iC ,.""." permission. ExtMp6ng, q/J01iII{/. Dr 01 __ ng wonting from ibis documlnt Is permlnBd DIlly wfIh 1hB ... "", _ porm/ssion uf ASFE, and only for PUl1JC*s of schoIsrf.t I'8Sf1i/Iell or tJook review. Only msmlMrs of ASFE may USB this docum~ as a comp/6rnInt to Of SS IJIINmenr of, geoIBthnlcaJ IIt{JlntJetlng report Any othBr firm. IndfvldlllJl. rx other fHItIly thBt so U$9S this docufflfJf/t withoot tmnu an ASFE member could be committing negHgent Of intBfltiOfJaJ (frJuduleot) misrspmentatio", IIGER06045.0M September 23, 2013 ES-2995 The Conner Homes Group, LLC 846 -108th Avenue Northeast Bellevue, Washington 98004 Attention: Ms. Jieun Shon Dear Ms. Shon: Earth Solutions NW LLC • GeotechniGll Engineering • Construction Monitoring • EnvironmenlaJ Sciences Earth Solutions NW, LLC (ESNW) is pleased to present this report titled "Geotechnical Engineering Study, Proposed Panther Lake Residential Subdivision, Renton, Washington". This study has been prepared to address the feasibility of the proposed development from a geotechnical standpoint. The proposed 33 residential lot development is bordered to the west by an off-site steep slope. Based on the conditions observed during our fieldwork, the subject site is underlain primarily by native soils consisting of medium dense to very dense glacial till. Groundwater seepage was observed in one test pit at a depth of approximately five feet below existing grade. Based on the results of our study, the proposed development is feasible from a geotechnical standpoint. The residential buildings and associated structures can be supported on a conventional foundation system bearing on competent native soil or structural fill. Where loose or unsuitable soil conditions are exposed at foundation subgrade elevations, compaction of the soils to the specifications of structural fill, or overexcavation and replacement with structural fill, may be necessary. This report provides recommendations for critical areas assessment, foundation design, structural fill recommendations, and other geotechnical recommendations. The opportunity to be of service to you is appreciated. If you have any questions regarding the content of this geotechnical engineering study, please call. Sincerely, EARTH SOLUTIONS NW, LLC \.A-l ( h:7' Henry T. Wright, E.I.T. Staff Engineer 1805· B6th Place N.E .• Suite 201 • Bellevue. WA 98005 • (425) 449-4704 • FAX (425) 449-4711 TABLE OF CONTENTS ES-2995 PAGE INTRODUCTION ..................................................................... ... 1 General .................................................................... ...... 1 Project Description ........................................................... 2 Surface ............................................................................ 2 Slope Reconnaissance....................................................... 2 Subsurface... .......... .... ..... ......... ... ... ... ... ... ...... ... ... ... ... ... .... 3 Groundwater.............. ....................................................... 3 CRITICAL AREAS AND GEOLOGIC HAZARDOUS AREAS ASSESSMENT............ ...... ........................ ........................... ........ 3 Site and Construction Plans ......................................................... 3 Landslide Hazard... ............................................................. 3 Steep Slopes............................................. ........................... 4 Erosion Hazard............................... ............ ..... ........ ............ 4 Analysis of Proposal..................................................................... 5 Minimum Critical Area Buffer and Setback...... ........................... 5 DISCUSSION AND RECOMMENDATIONS ....................................... 5 General.. ........................................................................... 5 Site Preparation and Earthwork................... ......................... 6 Erosion Control........................... ........... ............................. 6 In-Situ Soils......... ........ .......................... ............................... 6 Wet Season Grading......................... ..................... ............. 6 Structural Fill... ...... ......... .......... ......... ................ .................. 7 Excavations and Slopes ...................................................... 7 Foundations...... ................................................................ 7 Seismic Considerations........... ...... ........ ................................ 8 Slab-on-Grade Floors............... ... ... ... ... ... ... ... ....... ... ... ... ... ... 8 Retaining Walls.................................................... .............. 8 Drainage ............................................................................ 9 Utility Trench Backfill.......................................................... 9 Pavement Sections............ ......... .................. ...................... 10 LIMITATIONS... ......... ............... ........................ ........................... 10 Additional Services......... ............ ..................... ............ ...... 10 Earth Solutions NIN. LLC GRAPHICS PLATE 1 PLATE 2 PLATE 3 PLATE 4 APPENDICES Appendix A Appendix B TABLE OF CONTENTS Continued ES-2995 VICINITY MAP TEST PIT LOCATION PLAN RETAINING WALL DRAINAGE DETAIL FOOTING DRAIN DETAIL Subsurface Exploration Test Pit Logs Laboratory Test Results Sieve Analysis Results Earth Solutions NW, LLC General GEOTECHNICAL ENGINEERING STUDY PROPOSED PANTHER LAKE RESIDENTIAL SUBDIVISION RENTON, WASHINGTON ES·2995 INTRODUCTION This geotechnical engineering study was prepared for the proposed 33 lot residential development at 18647 -108th Avenue Southeast in Renton, Washington. The purpose of this study was to prepare geotechnical recommendations for the proposed development. To complete the scope of services detailed in our proposal PES·2995 dated August 20, 2013, we performed the following: • Subsurface exploration and characterization of soil and groundwater conditions by way of test pits excavated on the accessible areas of the site; • Laboratory testing of soil samples obtained during field exploration; • Engineering analyses, and; • Preparation of this report. The following documents and/or resources were reviewed as part of our report preparation; • Geologic Map of the Renton Quadrangle; • Conceptual Site Plan Provided by the Client, dated May 28, 2013; • The City of Renton online GIS property research database, and; • City of Renton Critical Areas Regulations (4-3-050J). Earth Solutions NW, LLC The Conner Homes Group, LLC September 23,2013 Project Description ES-2995 Page 2 Based on the plans provided to us, the site will be developed with 33 single family residential lots with associated roadways and stormwater facilities. Based on the City of Renton GIS data, sensitive and protected slopes are located along and adjacent to the western margins of the subject site. Grading activities will likely include cuts and fills to establish the planned building lots and access roadway alignments. Site improvements will also include underground utility installations and construction of stormwater detention facilities. Based on the conceptual site plan provided to us, we estimate cuts and fills to establish finish grades throughout the site will be on the order of two to eight feet on average; however, grading plans were not available at the time this report was prepared. Engineered rockeries or modular block walls may also be utilized as part of the overall grading plan. A storm tract is mapped along the western portion of the site. We anticipate the proposed residential structures will consist of relatively lightly loaded wood framing supported on conventional foundations. Based on our experience with similar developments, we estimate wall loads on the order of 2 kips per linear foot and slab-on-grade loading of 150 pounds per square foot (psf). If the above design assumptions are incorrect or change, ESNW should be contacted to review the recommendations in this report. ESNW should review the final design to verify that our geotechnical recommendations have been incorporated into the plans. Surface The subject site is located south of Southeast 186th Street at 18647 -108 th Avenue Southeast in Renton, Washington, as illustrated on the Vicinity Map (Plate 1). The site consists of six parcels totaling approximately 7.18 acres and is comprised of forested land through the northwestern and southwestern portions of the site with multiple residential structures and cleared land in the central and northeast portions of the site. Topography of the site consists of a slight west facing slope which becomes moderate to steep at the western margins of the site. The Test Pit Location Plan (Plate 2) illustrates the approximate limits of the property. Slope Reconnaissance During our fieldwork, we performed a visual slope reconnaissance across portions of the steep slope areas of the site as well as off-site to the west. The main focus of our reconnaissance was to identify signs of instability or erosion hazards along the slope areas. The typical instability indicators include such features as; head scarps, tension cracks, hummocky terrain, groundwater seeps along the surface and erosion features such as gulleys and rills. During the slope reconnaissance, a gulley aligned perpendicular to Panther Creek was observed adjacent to the northwest corner of the site, as well as a shallow head scarp approximately six to eight feet in height west of the property margins indicating minor surficial instability. In general, based on the slope reconnaissance, stability of the slope areas can be characterized as moderate. E.~h Solutions NW. LLC The Conner Homes Group, LLC September 23, 2013 Subsurface ES-2995 Page 3 As part of the subsurface exploration, six test pits were excavated on accessible portions of the site for purpose of assessing the soil conditions. Please refer to the test pit logs provided in Appendix A for a more detailed description of the subsurface conditions. Topsoil was encountered to an average approximate depth of 6 to 12 inches. Underlying the topsoil, medium dense brown sandy silt and silty sand was observed (Unified Soil Classification ML and SM, respectively), transitioning to dense to very dense at an average depth of three to five feet below existing grades. The referenced geologic map of the area identifies glacial till (Qgt) across the site. The soil conditions observed at our test sites generally correlate with glacial till (Qgt). Groundwater Groundwater seepage was encountered during our fieldwork at test pit TP-4. The seepage was observed at approximately five feet below existing grade and likely represents perched groundwater. The presence of groundwater seepage should be expected in deeper site excavations such as deeper foundation and utility trench excavations. Groundwater seepage rates and elevations fluctuate depending on many factors, including precipitation duration and intensity, the time of year, and soil conditions. In general, groundwater elevations and flow rates are higher during the wetter, winter months. CRITICAL AREAS AND GEOLOGIC HAZARDOUS AREAS ASSESSMENT As part of this geotechnical engineering study and critical areas report, the City of Renton Critical Areas Regulations (4-3-050J) were reviewed. Per the City of Renton Critical Areas Regulations requirements, the following topics related to development plans and site conditions are addressed. Site and Construction Plans The attached Test Pit Location Plan (Plate 2) illustrates a conceptual layout of the proposed 33 residential lot development. The building pad elevations witt vary according to existing grades. We anticipate the maximum cuts for the proposed development will be on the order of six to eight feet. A storm tract is mapped along the western margins of the site, adjacent to off-site steep slopes. Based on review of the referenced section of the City of Renton Municipal Code, as well as City of Renton GIS data, landslide hazards, steep slopes, and erosion hazards are considered for the subject development. Landslide Hazard With respect to landslide hazard areas, Part 4-3-050J-1 b of the City of Renton Critical Areas Regulations defines landslide hazard areas as the following: Earth Solutions NW, LLC The Conner Homes Group, LLC September 23,2013 • Low Landslide Hazard: Areas with slopes less than 15 percent. ES-2995 Page 4 • Medium Landslide Hazard: Areas with slopes between 15 percent and 40 percent and underlain by soils that consist largely of sand, gravel or glacial till. • High Landslide Hazards: Areas with slopes greater than 40 percent and areas with slopes between 15 percent and 40 percent and underlain by soils consisting largely of silt and clay. • Very High Landslide Hazards: Areas of known mappable landslide deposits. The off-site natural slope adjacent to the western margins of the site is not mapped as a landslide hazard by the City of Renton GIS data, however, based on a greater than 40 percent slope condition it is considered a high landslide hazard by the City of Renton Critical Areas Regulations. As previously described in the Slope Reconnaissance section of this study, a head scarp approximately six to eight feet in height was observed along the off-site natural slope, indicating recent, minor surficial instability. However, as the slope is underlain by glacial till, the overall global stability of the slope areas can be characterized as moderate. Steep Slopes With respect to steep slope critical areas, the referenced section of the Renton Code defines steep slopes as follows: • Sensitive Slopes: Areas with slopes between 25 percent and 40 percent. • Protected Slopes: Areas with slopes greater than 40 percent. Based on our observations and review of the City of Renton GIS data, sensitive and protected slopes are present along and adjacent to the western margins of the property. In general, based on the slope reconnaissance, stability of the slope areas can be characterized as moderate. Erosion Hazard With respect to erosion hazard areas, the referenced section of the Renton Code defines erosion hazards as follows: • Low Erosion Hazard: Areas with soils characterized by the Natural Resource Conservation Service as having slight or moderate erosion potential, and that slope less than 15 percent. • High Erosion Hazard: Areas with soils characterized by the Natural Resource Conservation Service as having severe or very severe erosion potential, and that slope more steeply than 15 percent. Earth Solutions f'NJ, LLC The Conner Homes Group, LLC September 23, 2013 ES-2995 Page 5 The off-site sloped areas adjacent to the western margins of the site would be severely susceptible to erosion, in our opinion. However, the on-site sloped areas and areas adjacent to the top of off-site slopes are classified as a low erosion hazard and would have a low susceptibility to erosion, in our opinion. In our opinion, the planned development will not increase the erosion hazard at the site, provided appropriate Best Management Practices are implemented during the earthwork and development activities. General guidelines for erosion control are provided in the Site Preparation and Earthwork section of this study. Analysis of Proposal The planned development activity will involve grading and construction of a 33 residential lot development with associated improvements adjacent to the steep slope area to the west. The proposed development activity will include a storm tract adjacent to the off-site slope area west of the site. As previously described, the on-site slopes and areas adjacent to the top of the off- site slopes exhibit good stability, and the planned development activity will not involve alterations to the areas of 40 percent slope. The proposed development activity is feasible in our opinion, and will not decrease stability of the site or surrounding properties. The project designs must comply with the City of Renton Critical Areas Regulations. Minimum Critical Area Buffer and Setback In our opinion, the proposed development activity can be completed as currently planned without adversely impacting the slope area along and adjacent to the western margins of the site. Sections 4-3-050J5 and 4-3-050J6 specify the requirements for development on sites which contain protected and sensitive slopes. The code requires erosion control measures, slope stabilization, and buffer zones. The proposed storm tract structure(s} to be located adjacent to the steep slope area should be setback at least 25 feet from the top of the slope with grading activities setback at least 10 feet from the top of the slope. Given the overall stable characteristics of the on-site slopes and areas adjacent to the top of off-site slopes, it is our opinion that a 25 foot setback of the proposed storm tract structure/s is feasible from a geotechnical standpoint. DISCUSSION AND RECOMMENDATIONS General Based on the results of our study, in our OpiniOn, construction of the proposed residential development at the subject site is feasible from a geotechnical standpoint. The primary geotechnical considerations associated with the proposed development include the steep slope setback, foundation support, structural fill placement, and the suitability of the on-site soils for use as structural fill. The proposed structures can be supported on conventional spread and continuous foundations bearing on undisturbed competent native soil or structural fill. Where loose, organic or other unsuitable materials are encountered at or below the footing subgrade elevation, the material should be removed and replaced with structural fill, as necessary. Earth Solutions mv. LLC The Conner Homes Group, LLC September 23,2013 ES-2995 Page 6 This study has been prepared for the exclusive use of The Conner Homes Group, LLC and their representatives. No warranty, expressed or implied, is made. This study has been prepared in a manner consistent with the level of care and skill ordinarily exercised by other members of the profession currently practicing under similar conditions in this area. Site Preparation and Earthwork Grading plans were not available at the time this report was prepared. However, given the existing grades, grading for the new development is anticipated to consist of cuts and fills of up to eight feet. Once the existing vegetation and topsoil has been cleared, grading operations can commence. Erosion Control Temporary construction entrances and drive lanes, consisting of at least one foot of quarry spa lis can be considered in order to minimize off-site soil tracking and to provide a temporary road surface. Temporary slopes and stockpiles should be covered when not in use. Surface water should not be allowed to flow down the face of any natural or cut slope, nor should water be allowed to pond near the top of any slope. Silt fencing should be installed along the margins of the property as well as at the top of on-site slopes of 40 percent or greater. Proper care and measures should be taken to ensure that development does not adversely affect the natural slope areas. Erosion control measures should conform to the Washington State Department of Ecology (DOE) and city of Renton standards. In-situ Solis The soils encountered throughout the majority of the test sites have a moderate to high sensitivity to moisture and were generally in a moist condition at the time of the exploration (September 2013). The soils anticipated to be exposed at this site will degrade rapidly if exposed to moisture. In general, soils encountered during site excavations that are excessively over the optimum moisture content will require aeration or treatment prior to placement and compaction. Conversely, soils that are substantially below the optimum moisture content will require moisture conditioning through the addition of water prior to use as structural fill. An ESNW representative should determine the suitability of in-situ soils for use as structural fill. If the in-situ soils are determined to not be suitable for use as structural fill, use of a suitable imported soil may be necessary. Wet Season Grading If grading takes place during the wetter, winter or spring months, a contingency in the project budget should be included to allow for export of native soil and/or existing fill and import of structural fill as described below. Earth Solullons NW, LLC The Conner Homes Group, LLC September 23,2013 Structural Fill ES-2995 Page 7 Structural fill is defined as compacted soil placed in foundation, slab-on-grade, and roadway areas. Fills placed to construct permanent slopes and throughout retaining wall and utility trench backfill areas are also considered structural fill. Soils placed in structural areas should be placed in loose lifts of 12 inches or less and compacted to a relative compaction of 90 percent, based on the laboratory maximum dry density as determined by the Modified Proctor Method (ASTM D-1557). For soil placed in utility trenches underlying structural areas, compaction requirements are dictated by the local city, county, or utility district, and in general are specified as 95 percent relative compaction. The upper 12 inches of slab-on-grade and pavement area subgrade should also be compacted to a relative compaction of at least 95 percent. Excavations and Slopes The Federal Occupation Safety and Health Administration (OSHA) and the Washington Industrial Safety and Health Act (WISHA) provide soil classification in terms of temporary slope inclinations. Based on the soil conditions encountered at the test pit locations, the weathered native soils encountered in the upper approximately four feet of the test pit locations and where fill and/or groundwater seepage is exposed are classified as Type C by OSHAIWISHA. Temporary slopes over four feet in height in Type C soils must be sloped no steeper than 1.5H: 1V (Horizontal:Vertical). Medium dense to dense native soils encountered below about four feet where no groundwater seepage is exposed would be classified as Type B by OSHAIWISHA. Temporary slopes over four feet in height in Type B soils must be sloped no steeper than H:1V. The presence of perched groundwater may cause caving of the temporary slopes due to hydrostatic pressure. ESNW should observe site excavations to confirm the soil type and allowable slope inclination are appropriate for the soil exposed by the excavation. If the recommended temporary slope inclination cannot be achieved, temporary shoring may be necessary to support excavations. Permanent slopes should maintain a gradient of 2H:1V, or flatter, and should be planted with vegetation to enhance stability and to minimize erosion. A representative of ESNW should observe temporary and permanent slopes to confirm the slope inclinations are suitable for the exposed soil conditions, and to provide additional excavation and slope recommendations, as necessary. Foundations Based on the results of our study, the proposed buildings can be supported on conventional spread and continuous footings bearing on competent native soil or structural fill. Where loose or unsuitable soil conditions are observed at foundation subgrade elevations, compaction of the soils to the specifications of structural fill, or overexcavation and replacement with granular structural fill may be necessary. Provided the building will be supported as described above, the following parameters can be used for design of the new foundations: Earth Solutions NW, LLC The Conner Homes Group, LLC September 23,2013 • Allowable soil bearing capacity • Passive earth pressure • Coefficient of friction 3,000 psf 300 pcf (equivalent fluid) 0.40 ES-2995 Page 8 A one-third increase in the allowable soil bearing capacity can assumed for short-term wind and seismic loading conditions. With structural loading as expected, total settlement in the range of one inch is anticipated, with differential settlement of about one-half inch. The majority of the settlements should occur during construction, as dead loads are applied. Seismic Considerations The 2009 Intemational Building Code specifies several soil profiles that are used as a basis for seismic design of structures. If the project will be permitted using the 2009 IBC, based on the soil conditions observed at the test sites, Site Class C, from table 1613.5.2, should be used for design. The 2012 IBG recognizes ASCE for seismic site class definitions. If the project will be permitted under the 2012 IBC, in accordance with Table 20.3-1 of ASCE, Minimum Design Loads for Buildings and Other Structures, Site Class C, should be used for design. In our opinion, liquefaction susceptibility at this site is low. The relative density of the site soils and the absence of a uniform, shallow groundwater table is the primary basis for this designation. Slab-On-Grade Floors Slab-on-grade floors should be supported on a firm and unyielding subgrade consisting' of competent native soil or at least 12 inches of structural fill. Unstable or yielding areas of the subgrade should be recompacted or overexcavated and replaced with suitable structural fill prior to construction of the slab. A capillary break consisting of a minimum of four inches of free draining crushed rock or gravel should be placed below the slab. The free draining material should have a fines content of five percent or less (percent passing the #200 sieve, based on the minus three-quarters inch fraction). In areas where slab moisture is undesirable, installation of a vapor barrier below the slab should be considered. If used, the vapor barrier should consist of a material specifically designed to function as a vapor barrier and should be installed in accordance with the manufacturers specifications. Retaining Walls Retaining walls must be designed to resist earth pressures and applicable surcharge loads. The following parameters can be used for retaining wall design: Earth Solutions NW. LLC The Conner Homes Group, LLC September 23,2013 • Active earth pressure (yielding condition) • At-rest earth pressure (restrained condition) • Traffic surcharge (passenger vehicles) • Passive earth pressure • Coefficient of friction • Seismic surcharge 'Where H equals the retained height 35 pcf 55 pcf ES-2995 Page 9 70 psf (rectangular distribution) 350 pcf 0.40 6H* (active condition) 14H* (at rest condition) Additional surcharge loading from adjacent foundations, sloped backfill, or other loads should be included in the retaining wall design. Drainage should be provided behind retaining walls such that hydrostatic pressures do not develop. If drainage is not provided, hydrostatic pressures should be included in the wall design. Retaining walls should be backfilled with free draining material that extends along the height of the wall, and a distance of at least 18 inches behind the wall. The upper one foot of the wall backfill can consist of a less permeable soil, if desired. A perforated drain pipe should be placed along the base of the wall, and connected to an approved discharge location. A typical retaining wall drainage detail is provided on Plate 3. Drainage Groundwater seepage was observed at one test pit location at a depth of five feet below grade during our fieldwork (September 2013). Perched groundwater seepage should be expected in site or utility excavations. Temporary measures to control groundwater seepage and surface water runoff during construction will likely involve interceptor trenches and sumps, as necessary. In our opinion, perimeter footing drains should be installed at or below the invert of the building footings. A typical footing drain detail is provided on Plate 4 of this report. Utility Trench Backfill In our opinion, the soils observed at the test sites are generally suitable for support of utilities. In general, the soils observed at the test pit locations should be suitable for use as structural backfill in the utility trench excavations, provided the soil is at or near the optimum moisture content at the time of placement and compaction. Moisture conditioning of the soils may be necessary at some locations prior to use as structural fill. Utility trench backfill should be placed and compacted to the specifications of structural fill provided in this report, or to the applicable requirements of the city of Renton. Earth Solutions Wo/, LLC The Conner Homes Group, LLC September 23, 2013 Pavement Sections ES-2995 Page 10 The performance of site pavements is largely related to the condition of the underlying subgrade. To ensure adequate pavement performance, the subgrade should be in a firm and unyielding condition when subjected to proofrolling with a loaded dump truck . Structural fill in pavement areas should be compacted to the specifications detailed in the Site Preparation and Earthwork section of this report . It is possible that soft , wet , or otherwise unsuitable subgrade areas may still exist after base 9rading activities . Areas containing unsuitable or yielding subgrade conditions may require remedial measures such as overexcavation and thicker crushed rock or structural fill sections prior to pavement. Cement treatment of the subgrade soil can also be considered for stabilizing pavement subgrade areas . For relatively lightly loaded pavements subjected to automobiles and occasional truck traffic , for preliminary design purposes , the following pavement sections can be considered : • Two inches of HMA placed over four inches of CRB , or ; • Two inches of HMA placed over three inches of ATB . Heavier truck-traffic areas generally require thicker pavement sections depending on site usage, pavement life expectancy , and site traffic . For preliminary design purposes , the following pavement sections for heavy traffic areas can be considered : • Three inches of hot mix asphalt (HMA) placed over six inches of crushed rock base (CRB), or; • Three inches of HMA placed over four and one-half inches of asphalt treated base (ATB). The HMA, ATB and CRB materials should conform to WSDOT specifications . LIMITATIONS The recommendations and conclusions provided in this geotechn ical engineering study are professional opinions consistent with the level of care and skill that is typical of other members in the profession currently practicing under similar conditions in this area . A warranty is not expressed or implied . Variations in the soil and groundwater conditions observed at the test pit locations may exist, and may not become evident until construction . ESNW should reevaluate the conclusions in this geotechnical engineering study if variations are encountered . Additional Services ESNW should have an opportunity to review the final design with respect to the geotechnical recommendations provided in this report . ESNW should also be retained to provide testing and consultation services during construction. Earth Solutions NW, LLC 'WI' fI .• ,JJIf' ... J' Refe ren ce: King Co unty , Wash ington Map 6 86 By The Tho ma s Gu ide Rand Mc Na lly 32 nd Edit ion NOT E: This plate may contain areas of color. ESNW can no t be responsible for any subsequen t misinterpre ta tion of the informa tion resulting fro m bla ck & wh ite reprocluct ions of th is plate . Vicinity Map Panther Lake Subdiv is ion Renton , Washi ngton Drw n. G LS Date 09/16/2013 Proj . No . 2995 Checked HT W Dat e Sep t. 2013 Plate ;" <!: (j) <' \ '- ~: ~. {- n', !j I I TP-3 1---, I , 3!~-'1 ,., TP-41 -0- I -----'I ",' " I -0- TP-61 Ie , I I ....:..:....._ 'TP-11 , 'r TP-21 -0- I. ---------------,---- I c ') 4 :3 ? 29 30 J./.18/ -j ~:'G ;jb J I 31 .V 1 1 'I 'I 33-l- TP-51 ~----- -'_. ----- C~'ee; ~>;'I,'it j 1 , ___ 1 :! . .: ::3 L' -l , 1 21 I 19 18 --, D(Ne','/c:y I -r-- . _______ J-- -1 uJ vi u.J :J 6J ~ J: I-- 00 o o 100 200 1"=100' i ~ LEGEND TP-1-!-Approximate Location of ESNW Test Pit, Proj. No. ES-2995, Sept. 2013 1 -l I 1 ___ I Subject Site -l4 Proposed Lot Number NOTE: The graphics shown on this plate are not intended for design purposes or precise scale measurements, but only to illustrate the approximate tesllocations relative to the approximate locations of existing and lor proposed site features. The information illustrated is largely based on data provided by the client at the time of our study. ESNW ""nnot be responsible for subsequent design changes or interpretation of the data by others. NOTE: This plate may contain areas of color. ESNW cannot be responsible for any subsequent miSinterpretation of the information resulting from black & white reproductions of this plate. <: s:::::.Q ~.~ g a....~ - <:"'C Cl o..c .~ :;:::::::::I..c <Il (J) CI) Uai-!J 0-",> -'<Il .-=: ---1 C c-~o _Q)"'E (J)'<: ai ~"En:: <Il C- Drwn. By GLS Checked By HTW Date 09/16/2013 Proj. No. 2995 Plate 2 18" Min. 0" 0" .. 0" .. 0" cO .. .0 00 .. "0" 0" NOTES: o Q'b 0 0"'0 CI 0 OO€)"Q0 0.. '" .. 0 "0 0 .. o 0 0 o <> 0 ",0 .. "00 00 ,,0 0'" .... 0" °",000 A .. 0 .. ac() • .... .. v '" 00"" 0 .. on 0° .... 0° .. 0 i!f 0 .. 0 .. 0'"'" .. o ° 0 " "'0 0" 0 00 0 0000°900°0 .. Q 00 00 q og 00000000°000 .. ,.p 0 .. 0 .. .. u 00 00 .. "0 .. '" 0.. .... 0 00 °0 °0 0", 000" .. 0 d .. .." 0", " .. (J.,'" .. .. .. St -0" OOOOOOCl~U .. .. .... ooQoot;° °0° 000000 QOn'g .. 00 .. IY 0 00 0 .. 0 .. 0 .. .. 0 0 0 00 .. 00 .. .. .. 0... 0° .. oOO-X 000 .. " 00 0 0 0 6' o Ii .. 0 00% '" o • Free Draining Backfill should consist of soil having less than 5 percent fines. Percent passing #4 should be 25 to 75 percent. Structural Fill Perforated Drain Pipe (Surround In Drain Rock) • Sheet Drain may be feasible in lieu of Free Draining Backfill, per ESNW recommendations. SCHEMATIC ONLY -NOTTO SCALE NOT A CONSTRUCTION DRAWING • Drain Pipe should consist of perforated, rigid PVC Pipe surrounded with 1" Drain Rock. LEGEND: Free Draining Structural Backfill 1 inch Drain Rock RETAINING WALL DRAINAGE DETAIL Panther Lake Subdivision Renton, Washington Drwn. GLS No. 2995 Checked HTW Date Sept. 2013 Plate 3 NOTES: • Do NOT tie roof downspouts to Footing Drain. • Surface Seal to consist of Perforated (Surround 12" of less permeable, suitable soil. Slope away from building. LEGEND: Surface Seal; native soil or other low permeability material. 1" Drain Rock 2" (Min.) Drain Pipe 1" Rock) SCHEMATIC ONLY -NOT TO SCALE NOT A CONSTRUCTION DRAWING ~ Earth ~ Solutions NWw ~ h Solutions NWLL< leal Engineering Const! ucrion tv' 0111toll ~ ~ and Environmental SClenCQS FOOTING DRAIN DETAIL Panther Lake Subdivision Renton, Washington Drwn. GLS Date 09/16/2013 Proj. No. 2995 Checked HTW Date Sept. 2013 Plate 4 Appendix A Subsurface Exploration ES-2995 The subsurface conditions at the site were explored by excavating six test pits at the approximate locations illustrated on Plate 2 of this report. The test pit logs are provided in this Appendix. The subsurface explorations were completed in September 2013. The test pits were advanced to a maximum depth of 11.5 feet below existing grades. Logs of the test pits advanced by ESNW are presented in Appendix A. The final logs represent the interpretations of the field logs and the results of laboratory analyses. The stratification lines on the logs represent the approximate boundaries between soil types. In actuality, the transitions may be more gradual. Earth Solutions NW, LLC JOB NO. E.S~2 ~~'5" CLIENT CO",~, }\O~ O~,,~\O~~~ TEST PIT NO. DATE Q/l?:./I'3 BY HTV\J I ELEVAnON y,. 2-TP-I CONTRACTOR N W E."",c..o-'IIo,+, (\~ SHEET I of \ .5O SURFACE CONDITIONS ~ i ~ -8 erOOC't'l 'o\~~ " -8 oj!! ::> 8 NOTE: DEPTH OF TOPSOIL & SOD I'l: Or Tl'SL. I-"tc?'~~~'=~_\~: - - --------------- - - ------------- r--t-I-.s-,--t-6-.fQ-l :r S M r!~;C~:LSj!~ ~_~l? -¥!~ f¥-q.yt\" J:1E!.4 LQ!,:! ~!. ... - - --- r r------------------------------------------- 1----11----11----1 3 r 1----1,..----11----1 4 r 1- I----t---II-----i 5- 1-------------------------------------------- -------------------------------------------- SS' \ ..... 0 ~\LP.-~~~':--:f6-~~-m--~-lJ-.r~--;D:·::~~:-::~·-SSI~rcr:cr::..L· ~&i-~--~: ~D. . .1 M.i:-~-.rcr.".~--~-..f: "-}g--~-s&--:.:-=1- J---+--+--I s-I-i 1'1 L Moi,.t 6,S' 15.0 t-tr~~-~-~~:.fi :+6.]-~i£ia,;""" .. '"'~. ~s.w;~·J;~.-5Ul'lLJT-:~-]MO.:-~;':1'~'.iQl..:-~0t!~~~;;.;~"K-~.;..=J J---+--I----I rl-M L N\ _, .L I • Lun~L _____________________________________ _ 1----11----11----1 8 J---+8_,_5-1' _I T_, '3--1 g-H_~~-O\\1--=---_-_-_-_--_-_-_-_--_-_-_-_--_-_-_-_--_-_-_-_--_-_-_-_--_-_-_-_--_-_-_-_---1- ---------------------------------------------I---II---t----I 0-- 1----+--+----1 1-- 1----+--+----1 2-- - I---II---t----I 3 ~ J---t--+---I 4-: I----t---I----I 5-r 1- 1----I1--+-----1 6 r 1----1---1---1 7+ r 1---1---1--; 8 r r--t---I----I 9-r Or Test Pit terminated at ~.S -------------------------------------------- -------------------------------------------- -------------------------------------------- r------------------------------------------- r------------------------------------------- r------------------------------------------- 1--------------------------------------------• ~------------------------------------------- t-------------------------------------------- 1-------------------------------------------- feet below eXisting grade. @ Groundwater (table I seepage) encountered at feet during excavation. Earth Solutions NWLLC JOB NO. CS-'2.0.0. '5 CLIENT (OO("lQ;>r ~ \)~.....(IO?~ TEST PIT NO . . --.-.. ~ TP-2. DATE ~/\?J/\~ BY HTW I ELEVATION L\~O CONTRACTOR NW E. "1.c.o.vo.+'C\ 0... SHEET lof \ "'~ -" 0..'<> '" 0..<: .!;; SURFACE CONDITIONS !ii ~ ~ t ;~\G ~f""It.SS EE m~ Ea. mOl OJ" " .! => 8 NOTE: DEPTH OF TOPSOIL & SOD \ ,," a mL 'TQ~SQ~I" ttd'1'~ _____________________________ _ J----+--+--------j 1 f-~\.. ~'O_~_'1_-SLI"T ... J.:1e.d\..'lI'S:\..~ ..... Mcb:r.t------ I-----I--f-----l 2- "2..S"' 16~ f-1-------------------------------------------- 1---____jf__-f__---'-1 3 f- I---____jf__-f______j 4 f- 1- I-----I--f-----l s- f- I---____j-~f______j 6 ~ \11.~ ,.::: 8 1----+---+------19- I---____jf__-f______j 0+ -------------------------------------------- -------------------------------------------- ~~~~_OJ1~~~~n----------------------- 1-------------------------------------------- !-------------------------------------------- ~___1~~.~___1 ~f-1-------------------------------------------- II.S \/0." 2-f-\:lO\\ ------------------------------------------- 1---+-------1r-----i 3- I---+--+-~ 4-f- t----+--+----i S-f- f- I-----+--+---j 6-f- f- 1 I---____jf__-f______j 8+ I-----I--f-----l 9- Of- Test Pit terminated at I \.5" 1-------------------------------------------- r------------------------------------------- 1-------------------------------------------- 1-------------------------------------------- 1--------------------------------------------• r------------------------------------------- !-------------------------------------------- feet below existing grade. @Groundwater (table I seepage) encountered at feet during excavation. Earth Solutions NWLLc JOB NO. E.S-2"" S-CLIENT Coone.('" \-\C*'I2!" ~\Oercv~.C'l-t TEST PIT NO. DATE Qh'?>/13 BY I-ITW I ELEVAnON 4YY TP-3 CONTRACTOR NW E"f..c.o.Vo.ti()~ SHEET I of \ GJ~ J! I!! .5 _GJ ~ .s::; 0..<:1 0.:6 EE Eo. a-mE m~ 0 ~Jl E 0 1 \.'5' q:?> I- 2- I- 3+ 0' \I.Li 4+ 1- 5+ (J) r.>GJ ~8 "'~L SM SURFACE CONDITIONS Li~'n+ 6n,)~ ,y NOTE: DEPTH OF TOPSOIL & SOD OD TQ~O"L.. -to '-" -fi - - -~~:-~Y~ii'.t;f!5~;4i.,-f'.---:.r li...::l"----" - ---tJj;";~ • I~------o-----~~-------------------------- I r------------------------------------------- r~~~-~-9J~-~u~~~----------------- f--------------------------------------------- ~~~Vj~-~~~-------------------------- 6' \'l.b 6 "o~ f------______________________________________ _ I---I--+----I 1-1- B-1- I----t---I---I ~ I---i---i-----i 0 I----t---I---I 1- 1---+--+------1 2- 1----+------1-----1---1 3- 1----1---+---1 4-= - I------l-----lf------l 5 - 1---1--+------1 6-- r- 7'1- I- I-----i-----'i-----i 8+ Test Pit terminated at <0 r------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- f---------------------------------------------• f--------------------------------------------- f--------------------------------------------- f--------------------------------------------- feet below existing grade_ @ Groundwater (table (seepage) encountered at feet during excavation. Earth Solutions NWLLC JOB NO. ES-1'W; CLIENT (onoe(' \-\O~ \h~lopt'C\en;-TEST PIT NO. DATE qjl';/I"!, BY I4-rW I ELEVATION l1~'S TP~4 CONTRACTOR NVJ E )(t.o-vQ+in<3 SHEET lof\ G>~ _G> o..Q E E mE ., Q.£ Eo. .. G> .. -C .!: III SURFACE CONDITIONS R a; [;l ~ SrG\W'\ b\~ ...... ~ .!! :l 8 NOTE: DEPTH OF TOPSOIL & SOD \ , Of--m.L..I-",[~P~Ql~ ~ JX ______________________________ _ 1---+--+---1 1 M L rll)ro~.!!. c:" .l·_r .s..u....l:: .... t1ed;\l'Cr\..,~ ... J~,!)js.i _____ _ 1---+--+-'" 2-f-7..' \9::\ 1-~f!\eL~!L~_~~~ ____________________ _ I----If--I---I 3-f- 1----11---1----1 4 IlH 4' 1---+--+----1 5+ 1---+--+----1 6-f- 1---+--+----1 rf- f- 1---+--+-'" 8-f-5' 1'1_"1 f-1---+--=-+----1 !rf- 1-------------------------------------------- ~CP~ __ Q.\.!~ j,,{:Q.~_~/J)~OlL ________________ _ r~~~~-~?~~~----------------------------- 1-------------------------------------------- -------------------------------------------- ~ f--------------------------------------------- 1---+--+----1 0 &:11'\ 10' \~~ --------------------------------------------1---+--+-'" 1-f- I---+---+-----tc 1---+---+-----t3- 1---+---+-----t4- 1----11--1---1 5- 1----11--1---1 6 7- -------------------------------------------- -------------------------------------------- -------------------------------------------- -------------------------------------------- --------------~----------------------------- -~------------------------------------------- 1---1--1---1 8 - ~ ~-------------------------------------------1---+---+--1 !r- 0'-1-------------------------------------------- Test Pit tenninated at 10 feet below existing grade. (NO) Groundwater (table €!pag3) encountered at S feet during excavation. Earth Solutions NWLLC JOB NO. 'E.~'lC\q $' DATE 0.. /l~"~ CONTRACTOR .. ~ -'" a..<l EE ll~ NW CLIENT (ot"lne.<, \-\O\'l\el. \»W\Ot>~flt TEST PIT NO. BY HlW E.. ')( co-vCX+iC\ ~ I ELEVATION '-\ C09 TP-S SHEET \ of I SURFACE CONDITIONS Gl'OISS ,_,. NOTE: DEPTH OF TOPSOIL & SOD 10 o 11>S\. 1 ML I -------------------------------------------- _ee~_~_~i~~_~~ ______________________ _ -------------------------------------------- r------------------------------------------- q' q.O r ~ r------------------------------------------- I-____ii__~i______i 0 1----+--+-.., 1-r 1----+--+-.., 2+ 1----+--+-.., 3-~ 1----+--+-.., 4-~ r I--Ji__-r-____i 5-r 1- 1---1---1----1 6+ 1---1---1----1 7 r I--i__-r-____i 8 1----+---1----1 9-- 0- Test Pit tenninated at q r------------------------------------------- r------------------------------------------- r------------------------------------------- r------------------------------------------- r------------------------------------------- r------------------------------------------- r-------------------------------------------• -------------------------------------------- feet below existing grade. ® Groundwater (table I seepage) encountered at feet during excavation. Earth Solutions NWl1.c JOB NO. E':l.~qq'S" CLIENT (O'l){)~ \1o~ D~ 1~Q.o-+ TEST PIT NO. DATE o,,/rM,'1;, BY HTW I ELEVATION 44 0 TP-6 CONTRACTOR NW E.x{.o.v~-tin~ SHEET \ 01\ .9!~ o.ll E E .E (f) SURFACE CONDITIONS ~~ 0-8 8~b\~S • OJ ::l Ul c: -8 J ~ 8 NOTE: DEPTH OF TOPSOIL & SOD \'2: C T~L .l9~9J~_!~_~~ _____________________________ _ ~-l----I---I 1 f--1"\ L e("C)Wt"I +0 _'i~~ _ ~ _ § llL .MctOiIlro ~~ ... .M.a:1S\: \b,~ ~ ------------------------------------------- ~___i~-~___i 3+ 4+ f-- ~-l----I---I 5+ 5' \,?>,C ~___i~-~--l 6+ ~-l----I---I rf-- ~------------------------------------------- f-. ~.-. N::;;;'"l::l.--:.-;..-...... -~ ... -------- ---- ---- - --- ~------------------------------------------- 1---1-8::"'-1-1 \.:....:T~ :~ 'aO~f...------------------------------------------- f--f...------------------------------------------- ~~~-~___i 0+ I----J.---J...-~ 1-f-- f-- 1---+--1---1 2- f-- 1---+--1---1 3- 1---+--1---1 4- I----J.---J...-~ 5-~ ~-+--+----I &1- f... 7 I--~-I____l 8-1- f... I----J.---J...--J 9-1- o Test Pit tennlnated at e ~------------------------------------------- ~------------------------------------------- f...------------------------------------------- f...------------------------------------------- f...-------------------------------------------• f...------------------------------------------- f...------------------------------------------- feet below existing grade. @ Groundwater (table I seepage) encountered at feet during excavation. Earth Solutions NWLlC Appendix B Laboratory Test Results ES-2995 Earth Solutions NW, LLC • Earth Solutions NW GRAIN SIZE DISTRIBUTION I' ! • 1805 -1361h Place N.E., Suite 201 Bellevue, WA 98005 Telephone: 425-264-3300 CUENT Conner Homes DevelQQm~nt PROJECT NAME Panther Lake Subdivision PROJECT NUMBER ES-2995 PROJECT LOCA nON Renton u.s. SIEVE OPENING IN INCH~S I U.S. SIEVE NUMBERS I HYDROMETER 8 ... 3 2 1.5 1 1/2 3 6 810 1416 20 30 40 5060 1001040200 100 I I [\' I I 95 r-.. \ 90 1\ 85 I~\ 80 I"-. i'-, '\ 75 "-[\ 70 ,\\ 65 ... :!: ~ 60 1\ ~ 55 II: 1\ w 50 z \ u: ... 45 z 1\ w 0 40 II: \ w n. 35 30 25 20 15 10 5 a 100 10 1 0.1 0.01 0.001 GRAIN SIZE IN MILLIMETERS I COBBLES I GRAVEL I SAND I SILT OR CLAY coarse fin. I coarse medium I fine J Specimen Identification Classification LL PL PI Cc Cu 0 TP-2 2.5ft. Brown Sandy SILT, ML ~ TP-4 10.Oft. Gray Blue Sandy SILT. ML l> TP~ 6.Oft. Gray Silty SAND with Gravel, 8M Specimen Identification 0100 060 030 010 %Gravel %Sand %Silt 1 %Clay 0 TP-2 2.5ft. 19 0.086 2.8 39.7 57.6 ~ TP-4 10.Oft. 9,5 0.4 37.2 62,3 l> TP~ 6.Oft. 19 0.374 16,6 53.3 30,1 EMAIL ONLY REPORT DISTRIBUTION ES-2995 The Conner Homes Group, LLC 846 _108th Avenue Northeast Bellevue, Washington 98004 Attention: Ms. Jieun Shon Earth Solutions NW, LLC Renton PANTHER LAKE PLAT TRIP GENERATION, ACCESS REVIEW AND TIF TRAFFIC LETTER January 22, 2014 JTE . Jake Traffic Engineering, Inc. Mark J. Jacobs. PE . PTOE. Pr esi dent 2614 39th Av e SW -Seatt le. WA 98116 -2503 Tel. 206.762 .1978· Cell 206.799 .5692 E-mail jaketraffic@comcasLnet RECEIVED FEB 1 3 2014 CITY OF RENTON PLANNING D~~::-__ _ JTE . Jake Traffic Engineering, Inc. . CONNER HOMES Attn: Rob Ri singer. Deve lopme nt Pr oject Manager 846 108"' Ave N E Bell ev ue. WA 98004 Re: Panther Lake Plat -Re nton Rent on Pr e-ap pl ica ti on #13-000413. Hark J. Jacobs, PE, PTOE President 261439 " Ave. SW -Seatde. WA 98116 -21 03 Tel. 106.761 .1978 -Cell 106.799.1691 E .... ij jakttralfi<@<omwlntt January 22. 2014 Trip Gen eration . Access Rev iew and T1F Traff ic Letter Dear Mr. Ri sin ger. I am pleased to pr ese nt th is Trip Gene rati on. Access and TIF Traffi c Letter for the 34 lot (32 net new) Panth e r Lak e Plat loc ated at 18655 108"' Ave. SE. in Renton . Primary access to t h e site is pro po se d via a new stre et intersec ti on with 108"' Av e. SE (SR -515) at th e SE 187'" Lan e alignm ent. Th e Ci ty of Renton required a second access be provided to the si t e. Thi s second access is also located on lOath Av e. SE about 260' so uth of th e primary access. I co ndu cted a field review t he si te and su rrounding street system. The study scope was det ermined pursua nt to pri o r work in the City of Renton on a sim i lar proje ct. review of th e City 's T1A Guidelines f or new devel o pmen ts and the Pre-application Meeting Notes . April 25, 2013 note s. Th e City pe ak hour trip threshold is 20 trips. The gen e ral format of this report is to describe th e proposed proje ct , calculate the traffic t hat would be generated by the project. review th e site accesses and ascerta in the Traffic Impact Fee for the project PROJECT INFORMATION Below is an aeria l i mage of t he s ite obtained from King County IMap: Figure 1 is a vicinity map showing the location of the proposed site and surrounding street network. Figu re 2 shows a preliminary site plan prepared by ESM Consulting Engineers . LLC . The site plan cons ist s of the 34 lot (32 net new ) Panther Lake Plat development and internal circu lation . Access to the site is proposed via a new street intersection with 108"' Avenue Southeast. >.1......-1 ,,,,,-,,,_,,,,0.1<11:"'" ._ .... r.r.~_ •• _~,~_ ....... __ ·.L_ .... COL~ coPY ONlY JTE, Inc. CONNER HOMES Attn: Rob Risinger, Development Project Manager January 22, 2014 Page -2- Full development and occupancy of the proposed Panther lake Plat project is anticipated to occur by 2014/2015, presuming the permits are issued in a timely manner. EXISTING ENVIRONMENT Project Site The project site is presently developed with two Single family detached homes that are to be removed to make way for the proposed development. Street System The primary streets within the study area and their classifications per the City of Renton Comprehensive Plan Figure 1-6 are depicted in the graphic to the right: One hundred eighth Avenue SE (SR -515) is a developed 5-lane Principal Arterial with a posted speed limit of 40 MPH. Traffic Volumes r; ,. The WSDOT Annual Traffic Reoort, 2012 identifies that 27,000 to 28,000 vpd use SR -515 in the site vicinity. Pedestrian Facilitjes Curb, gutter and sidewalk exist on both sides of 108"' Ave. SE (SR -515). Schools Renton School District identified students living in the subdivision would attend the following schools: ... Benson Hill Elementary: );> Nelsen Middle School: );> Lindbergh High School: 18665 -116"' Ave. SE Renton WA 98058 2403 Jones Ave. S. Renton WA 98055 16426 -128'" Ave. SE Renton WA 98058 Students attending the above schools would be eligible for bus transportation. Accident H istorv WSDOT electronically provided 3 years (January 1, 2010 to December 31, 2012) of accident data for SR -515 in the vicinity of the development site. I have reviewed the data, in ,.~ ...... " "" .,., ., .'J:, ','" .• ,'.. ., ,h.ot,.,".,'''' .................. J' •• COLOR COP~ ONl v CONNER HOMES Attn: Rob Risinger, Development Project Manager January 22, 2014 Page -3- JTE, Inc. particular in the site vicinity, -MP 4.3. Thirteen incidents are between MP 4.11 (n/o SE 192"" St.) and 4.B7 (s/o SE 200'" St.) in the 3 year time period. These 13 incidents correlate into an accident rate of about 0.6 incidents per million vehicle miles. The WSDOT 2011 Washington State Collision Data Summary identifies a collision rate of 2.07 and 2.57 incidents per million vehicle miles for Urban Principal and Minor Arterials, respectively. The above WSDOT accident rates are per million vehicle miles. SR -515 is a Principal Arterial. The calculated accident rate on SR -515 in the site vicinity is lower than the average and no apparent issue is noted. STREET IMPROVEMENT PROJECTS The City of Renton 6 year Transportation Improyement Proeram, 2012 to 2017 was reviewed. A portion of Exhibit 'A' from the program is depicted to the right: No TIP project is noted on 10Bth Ave. SE (SR -525). I have included the project map index in the Appendix of this letter. The 6 year TIP is available on the City's web site. I also reviewed WSDOT's web site for projects on SR -515 in the site vicinity. No project is noted. TRIP GENERATION AND DISTRIBUTION Definitions A vehicle trip is defined as a single or one direction vehicle movement with either the 41 !~ I Project Site ! ® • • ~I origin or destination (existing or entering) inside the proposed development. T"""';""-~."...~" ... '1O"~JI ,.".,_.,.,,, .. ",~ .... "." .""""'''."·,~,,",,<;'",,,,,,,,.T'-,'''r.'' COLOR coPY ~l Y JTE, Inc. CONNER HOMES Attn: Rob Risinger, Development Project Manager January 22, 2014 Page -4- Traffic generated by development projects consists of the following types: Pass-By Trips: Diverted Link Trips: Captured Trips: Primary (New) Trips: Trip Generation Trips made as intermediate stops on the way from an origin to a primary trip destination. Trips attracted from the traffic volume on a roadway within the vicinity of the generator but which require a diversion from that roadway to another roadway in order to gain access to the site. Site trips shared by more than one land use in a multi-use deve lopment. Trips made for the specific purpose of using the services of the project. The project site is currently developed with 2 single family detached homes that are to be removed to make way for the proposed development. I have taken into account the trips associated with the existing uses and have credited them towards the trips generated by the proposed development. The proposed Panther Lake Plat is expected to generate the vehicular trips during the average weekday, street traffic AM and PM peak hours as shown in Table 1. The trip generation for the project is calculated using trip rates from the Institute of Transportation Engineers (ITE) Trip Generation, 9 th Edition, for Single Family Detached Housing (ITE Land Use Codes 210). All site trips made by all vehicles for all purposes, including commuter, visitor, and service and delivery vehicle trips are included in the trip generation values. Based on my analysis, the trips generated by the Panther Lake Plat are calculated to be 305, 24 and 32 trips during the weekday, AM and PM peak hour, respectively. Trip Distribution The site traffic would is projected disperse to the north and south on 108th Ave. SE with a likely split of 60 and 40%, respectively. Renton's traffic effect threshold is 20 peak hour trips. No significant City intersections would be effected by site traffic. SITE ACCESS Sight Access Visibility: I field inspected the available stopping sight distance (SSD) and entering sight distance (ESD) at the proposed site access. The posted speed limit on 108'" Ave SE is 40 MPH and per prior correspondence with City of Renton, I understand the American Association of State Highway and Transportation Officials (AASHTO) criteria for sight distance is used. The ''-........ "._. "'_.' ..... _,: " .• ,.,_"" ." .. ~., •• _"" •• ''',,''"',< ........... ·' ...... 00' COLOR COPY OfItl ~ CONNER HOMES Attn: Rob Risinger, Development Project Manager January 22, 2014 Page -5- JTE,lnc_ AASHTO sight lines criteria are 305' for Stopping Sight Distance and 445' for Entering Sight Distance as obtained from the AASHTO A Policy on Geometric Design of Highways an Streets. The photographs below were taken in the vicinity of the primary site access intersection with 108th Avenue Southeast: Review of the proposed primary site access shows good sight lines. Vegetation, mail boxes and power pole items will need to be cleared appropriately. A second access to the project was incorporated pursuant Renton requirements. This access is about 260' south of the primary access. Good sight lines also exist at this location with appropriate clearing of vegetation and any other incidental impediment(s). Access Intersection Review: The project site traffic during the PM peak hour is projected at 34 PMPHT's (32 net new) with 21 entering the site (14 from the north and 8 from the south) and 13 exiting the site. A two way left turn lane exists on 108th Ave. East that provides left turn channelization. WSDOT Design Manual Figure 910-15 "Right Turn Lane Guidelines" was reviewed. Based on the WSDOT right turn figure a right turn radius would be appropriate. Right turning traffic is well below the minimum 20 PMPHT threshold needed to warrant a right turn pocket. A copy of the WSDOT figure is attached. 108/h Ave. SE Street Frontage: One hundred eighth Avenue SE (SR -515) is a developed 5-lane Principal Arterial. Renton Municipal Code identifies the standards for streets based on classification. Title IV Chapter 6 provides the Street Standards. Per the RMC a "Principal Arterial" can be between 4 and 7 -lanes. Adjacent to the site 108'" Ave SE is a developed 5-lane Principal Arterial street with a daily traffic volume of "-.:0-'_"" .j".,.." _",r,I."" ~ .. ,,~ '"~ ',.~, .. "'G_ k_ "~"""""""''''''''''''''''.'''''''_ COLD'! COPY ONLY CONNER HOMES Attn: Rob Risinger, Development Project Manager January 22. 2014 Page ·6· JTE, Inc. about 27,000 to 28,000 vpd. City staff commented on the street frontage in Pre-application Meeting Notes as follows: L Fxisting right-of-way width in Benson Road fronting the sile is 82 feeL Benson Road (SR 515) is dassifif"d as Prindpal Artf'fial To me-et the City's complete street st<lndards, str("ct improvements induding an 8-foot planting strip behind the existing curb, a 12-foot sidewalk (shared bike/pedestrian), a 2-loot strip back of sidewalk. storm drainage. and street lighting will be required. To buitd this street section, approximately 12.5 leet 01 right-ol-way will be required to be dedicated to the City along the project side in Benson. Final dE:>terrninalion of specific right-of way dNiiration will be confirmed when the survey and preliminary engineering. desisn is complete. 3 Applicant may submIt an application to the City requesting a modification of the street frontage improvements a'i outlined in City code 4~9-2S0CSd. I understand that a modification request to the City is to be made to maintain the existing developed street section; that makes sense. AGENCY TRAFFIC IMPACT MITIGATION REQUIREMENTS The City of Renton has a Traffic Impact Fee program per Ordinance #5670 effective January 1, 2013. The TIF is scheduled to be phased in over time. The Pre-application Meeting Notes identify the 2013 TIF at $717.75 per SFDU and the 2014 rate at $1,430.72. City of Renton online data, attached, indicates the 2014 at $1,452.30. Thus the TIF for the 32 net new SFDU's is projected to be $46,473.60 in 2014. The rate adjusts to $2,154.59 in 2015 and then to $2,856.89 in 2016. Access improvements per City and WSDOT requirements will be required. A modification request to maintain the exiting street frontage improvements is to be provided. Construct the internal street in conformance to City requirements. SUMMARY AND CONCLUSION This letter was prepared to identify the Trip Generation of the proposed project, review the Site Access Sight Lines and calculate the City's Traffic Impact Fee. Based on my analysis the proposed Panther Lake Plat project is expected to generate 305 net new daily and 32 PM peak hour trips. The City trip threshold is 20 peak hour trips, no City classified intersection would be effected by site traffic. Sight lines at the proposed accesses on 108'" Ave SE are good with provision appropriate vegetation clearing and removal of sight obstructions. A traffic impact fee of $22,968 is calculated to be contributed to the City of Renton's traffic impact fee program. ."H.·" ....... ~_.-~ r ..... ,"'"'''"' ... " ... l~'''''.·'''' COL~ COPY ONL ~ JTE. Inc. CONNER HOMES Attn: Rob Risinger, Development Project Manager January 22, 2014 Page '7 Based on my analysis I recommend that Panther Lake Plat be allowed with the following traffic impact mitigation measures. J, Construct site in accordance with applicable City requirements. , Install the site access intersections on 108"' Ave. SE to applicable Citv/WSDOT requirements );0 Pay lawful traffic impact mitigation fee. );0 Prepare a formal street modification request to allow 108"' Ave. SE street geometrics to be maintained. );0 Construct the internal subdivision street to City requireme"Ls. No other traffic mitigation should be necessary. Please contact me at 206.762.1978 or email me at if you have any questions. MJJ: mjj I EXPIRES 4131? D l'l Sincerely, Mark J. Jacobs, PE, PTOE, President JAKE TRAFFIC ENGINEERING, INC O/.i!.l.ZO/'{ J"' ..... ,,/ •. , ..• , .... ~ .. " """" ... , ..... ", .. ,'",_, __ " ~ ...... ~\'~""<·' ... ,S .......... l~, ... ..-" COl OR COPY ONt y JTE, Inc. VEHICULAR TRIP GENERATION TABLE 1 PANTHER LAKE PLAT -RENTON TRIP GENERATION, ACCESS REVIEW AND TIF TRAFFIC LETTER TIME TRIP TRIPS TRIPS TOTAL PERIOD RATE ENTERING EXITING Single Family Detached Housing (ITE Land Use Code 210, 32 net new lots) Average T ~ 9.52X 153 (50%) 152 (50%) Weekday AM Peak T ~ 0.75X 6 (25%) 18 (75%) Hour PM peak T ~ 1.0X 20 (63%) 12 (37%) Hour T ~ trips; X ~ number of net new lots (29) A vehicle trip is defined as a single or one direction vehicle movement with either the origin or destination (existing or entering) inside the study site. The above trip generation values account for all the site trips made by all vehicles for all purposes, including commuter, visitor, recreation, and service and delivery vehicle trips 305 24 32 .•.••. ,., .... ,,',_ ,.-.''0" .. _.-"'" .-•• _-......,.. ,_,p..-"' ..... "'-.,_.n" .... · ... , COLOR COPY OIliL Y JTE, Inc. 100 I I 80 " " E .:l 0 > c ....... ___ .-~ Consider right-tum lane 81 Con..oer right-tum ~ ~ podet or taper 1'1 ~ E 60 ~ '" 13 SBRI's and an .: i' ~ approach volume 840 (1) ~ '" a: PMPHT's :; 40 0 :x: "" .. .. "-20 Ra<I ... only P: ~ ~ ... ~:.-------- ® o o 100 200 300 400 500 600 700 Peak Hour Approach VolUme (OOHV)" NMin: [1) For taoo-L.ar"l' hignw.ays. uwo,.... P4'al'lOur DOH\.' idwough'" nghl-twnl. For multJl.an4.. "'Ig~ h!g"-a."s IpOSWdi ~ 45 fI"C)t\ or .abov.t us. h right-~ pull. haur ~ 'oo'OIurne (ttwoug:h + ngtlt-tum! Rl ~.aU 1hr" d ~ foItowtnog cor\drtlOMs ¥I' 1TNf1. rwc:k.IoP ~ nght-tum DDHV by 20 Th4' poRed spMd I!o -45 tnpf'I or ~5 • Th,. ~-tutTI volume is g~.r ~ -40 VPH' . Th4I.-_ now-~ro.cn votume (DOHV)tS IH5 th~ 300 VPH {3J For ~--tum ~r desq'1. Mil F IQU"" Q 11J.-11 [4J FI)I" ~-tlIm poctl't or """' deSlgf'l. Sft Faogure "1o.'e (e;) F'cw nght..tum ~ dntgrI. we F'igln "10-1; [6] For oMkhtion.,r ~1Cb~. Me Q1D.D7(3} DMi9n "~nu .. ' "12·01.02 tlCWH1""" 1007 Right-Tum Lane Guidelineslll Fi!lu,. i'O·t5 PiM#'# Pt0-37 (1) -The daily traffic volume on 1(}8th Ave SE is 27,000 to 28.000 vpd. The PM peak hour traffic is typically about 10% of the daily traffK:. thus about 2.800 vehicles during the PM peak hour. Projecting a 60/40 direcHonal split 58 and NS t respectively, about 1,680 vehicles are 58 in 2-lanes. thus 840 vpl .'~'_l.,,· "''!'''<'F''''''''''~'''' h~"'''' ,~ .... ~''' ... M-.'_ .. "\~ .... "","""""''''''''~''"'''''''' COlOff (X)py ONl 'f Project: Panther Lake Plat -Renton Location: 18655 108'" Ave. SE NORTH JTE. Inc. FIGURE 1 PANTHER LAKE PLAT -RENTON TRIP GENERATION, ACCESS REVIEW AND TIF TRAFFIC LETTER VICINITY MAP Project: Location: Panther lake Plat -Renton 18655 108th Ave. SE Note: An 8.5 )I 11 W copy of the site plan is included with this Traffic Letter ---------.. --------- ... ,.f ."".OM h'''''''''.''-....... --._ .. __ .. -_.-..... ------ ----~-.--..... ... ~-.--... - ----_ .... --_ . .!o':::_Y::'!. __ ------------------..... ------fJ!;' ...... ....-.. ~~seyr" ... !"' ... tr:" . -~.rpIib'!", __ PANTHER LAKE PLAT -RENTON NORTH Giit'uu --__ 1 __ - ==::.----------===_.- JTE, Inc. FIGURE 2 TRIP GENERATION, ACCESS REVIEW AND TIF TRAFFIC LETTER SITE PLAN .. I~l ....=: I --, -=.;- W<I~,,,,,,,,,,,,.,,, !>i' I~~ :.::= -,;:; ,., ~L~;, ,~\~i~';:f;e; IlIIiIiII !-•. , I, -'"+:; -' Iiij , I 1,lmmli!il!I,1 1 1~llm ",I 'j ~ .. w.~ ..• _ •...••.. , ~§~:;U$;I!.~ ~ , ~ i ~!j~,:m~l! ! -~ ............ "' ..... § § ,,,,,,,,,,,, ~ " i!mmn"~ ! w z -N'fId lYld ~ 3>1Vl 1::l3H.lNVd S3V140H 1::13NN08 1 PCI_ JO.w:J ~ , . I ' . , 9 , Iii ~ ~ , J " .. ~ ~ ; 11111';' . , !,! 'M I __ , ... _ _a._' .... '_ ----~ .• ...-....-.--, •. APPENDIX PREAPPLICATION MEETING FOR PANTHER LAKE PLAT PRE 13-000413 CITY OF RENTON Department of Community & Economic Development Planning Division April 25, 2013 Contact Information: Planner: Rocale Timmons, 425.430.7219 Public Works Plan Reviewer: Jan lilian, 425.430.7216 Fire Prevention Reviewer: Corey Thomas, 425.430.7024 Building Department Reviewer: Craig Burnell, 425.430.7290 Please retain this packet throughout the course of your project as a reference. Consider giving copies of it to any engineers, architects, and contractors who work on the project. You will need to submit a copy of this packet when you apply for land use and/or environmental permits. Pre-screening: When you have the project application ready for submittal, call and schedule an appointment with the project manager to have it pre-screened before making all ofthe required copies. The pre-application meeting is informal and non-binding. The comments provided on the proposal are based on the codes and policies in effect at the time of review. The applicant is cautioned that the development regulations are regularly amended and the proposal will be formally reviewed under the regulations in effect at the time of project submittal. The information contained in this summary is subject to modification and/or concurrence by official decision-makers (e.g., Hearing Examiner, Planning Director, Development Services Director, Department of Community & Economic Development Administrator, Public Works Administrator and City Council). DEPARTMENT OF COMMUNITY AND ECONOMIC DEVELOPMENT MEMORANDUM DATE: April 24, 2013 TO: Rocale Timmons, Planner FROM: Jan lliian, Plan Review ~ Panther Lake Plat SUBJECT: 18655 -lOS"' Avenue 5E PRE13-o1lO413 NOTE: The applicant is cautioned that information contained in this summary is preliminary and non- binding and may be subject to modification and/or concurrence by official city decision-makers. Review comments may also need to be revised based on site planning and other design changes required by City staff or made by the applicant. I have completed a preliminary review for the above-referenced proposal. The following comments are based on the pre-application submittal made to the City of Renton by the applicant. WATER Water service will be provided by Soos Creek Water and Sewer District. A water availability certificate will be required to be submitted to the City with the site plan application. SANITARY SEWER Sewer service will be provided by Saos Creek Water and Sewer District. A sewer availability certificate will be required to be submitted to the City with the site plan application. SURFACE WATER 1. There Is limited storm water conveyance system in Benson Road SE. 2. A drainage plan and drainage report will be required with the site plan application. The report shall comply with the City adopted 2009 King County Surface Water Manual and the 2009 City of Renton Amendments to the KCSWM, Chapters 1 and 2. All core and any special requirements shall be contained in the report. Based on the city's flow control map, this site falls within the Flow Control Duration Standard, Forested Site Conditions. The drainage report will need to follow the area specific flow control requirements under Core Requirement #3. Panther lake plat -PRE 13-00041 page 2 of 7. April 24, 2013 3. A geotechnical report for the site is required. Information on the water table and soil permeability, with recommendations of appropriate flow control BMP options with typical designs for the site from the geotechnical engineer, shall be submitted with the application. 4. Surface water system development fee is $1,120.00 for each new lot. Credit will be given to the existing homes. This is payable prior to issuance of the construction permit. 5. Separate structural plans will be required to be submitted for review and approval under a building permit for detention and or/water quality vault. Special inspection from the building department is required. 6. A Construction Stormwater General Permit from Department of Ecology is required if clearing and grading of the site exceeds one acre. The application is included with the pre-application packet. TRANSPORTATION 1. Existing right-of-way width in Benson Road fronting the site is 8Z feet. Benson Road (SR 515) is classified as Principal Arterial. To meet the City's complete street standards, street improvements including an 8-foot planting strip behind the existing curb, a 12-foot sidewalk (shared bike/pedestrian I, a Z-foot strip back of sidewalk, storm drainage, and street lighting will be required. To build this street section, approximately 12.5 feet of right-of-way will be required to be dedicated to the City along the project side in Benson. Final determination of specific right-of-way dedication will be confirmed when the survey and preliminary engineering design is complete. Z. Curb cuts proposed off SR 515 will require review by WSDOT. 3. Applicant may submit an application to the City requesting a modification o!the street frontage improvements as outlined in City code 4-9-Z50CSd. 4. LED street lighting will be required per City of Renton Standards. 5. Payment olthe transportation impact fee is applicable on the construction of the single family houses at the time of application for the building permit. The current rate of transportation impact fee is $717.75 per single family house. The impact fee forthis type of land use will increase on 1/1/Z014 to $1,430.72 per single family house. The transportation impact fee that is current at the time of building permit application will be levied, payable at,building pen)1it . l.. + I issue. o~ (;~e A../h.-.. r/'J r j,H&~..A 6. A traffic impact analysis is required when estimated vehicular traffic generated from a proposed development exceeds ZO vehicles per hour in either the AM (6:00 -9:00) or PM (3:00 -6:00) peak periods. A peak hour volume of ZO vehicles per hour would reiate to daily volume of approximately 200 vehicles per day. Generally. this includes residential plats of ZO lots or more and commercial sites that generate 20 vehicles per hour. Traffic study guidelines are included A4 with the pre-application packet. . \ .. < f< J /" ~ r r f\J () C-,~.,...r d-1 L-17( .) k (I ,,"~b-2;:) or '-"',"--f"" GENERAL COMMENTS -/11t-i~ IfJ ' Any proposed rockeries or retaining walls greater than four feet (4') in height will require a separate building permit, structural plans, and special inspection. H:\CED\Planning\Current Planning\PRFAPPS\13-()()()413.Rocale\Plan Review Comments PREB-Q00413.doc §'-~ N , -, ~ ~ ~il ~ " .. ~ M :g ~ '" 30;1 ~~ ·U ! ;;. ~ Ih ~ ~ ~ ~ ~ " In :;::: :;! ~ , ~ . : i ~ i ;,;~ ~;i I ~i IiI ! "'! "': ~ m m ~ ~ I 1'1-m ~ ~ ~ ;!; I . · ~ ~~j H ~ 0 ~! ~~ 1,,-Hl : ~ ~ ~ N N ~ ~ 0 1'1-• • ~ ~ il i • ~ ~ · . .5-5 :til ~ ~ ~-H g g 1,,-I t t f Ul -£ -£ '5 -5 g < ~ g < 0 11-~. f • ~ ~1 • • • -£-£ ~ 01 g g g g HI • • !f H g g ! g 1 I I I ~ ~ ~ :;; I ~ ~ ii ~ ~v: v: ~. .! I ! ~ ~ :;( ,,~ .! I ! 8 -~ ~ ~ , j ~ ~ s: ~ ~ ~ '" -' ~ ~ ~ .! :;; :: ~ 1 ~ $:;;'. < < • ~ h " . ' ~ ~ . e .. ~ a 1; . -~ < ~ Washington State Department of Transportation lynn Peterson SecretarY ot Tfans.portallur. (ktnheT X. :0 I "1, \1r. \lark Jacobs .III· Illc. ::614 _,9 111 .'\ \'t~ ~ \)" Seattle. WA 4X 116 Re: Collision Ilata Tr'ln~pon,lhon BlJIldlllq J:C M<ipl~ fJ,Jrl'-. .... ,~·".t· '~:'.I pc, Bc,~ .\ 73 IX, ('\!'1""'::'~<1 '.V,A :!~~<,' 1 -,-y.', JGO ;0:. ;00;,: (~I"T""( /...ft! e (ec..f/o-; <. +, I ~ "'.t'. i I. j,1 (. '-"'f'-- ..--eo, oJ .... i+ ~~h.(:+/c1t. t~ (.:J""'(~Jt . ..,4 In response t(1 your SC~lher 25 request. we have prepared a history of reponed collisions that occurrL·d on StatL' ROllte 51' I'~-' 1 to 11.28) Irom SF ~to S :3rd Sl. Oil '" in the \idnitv of SF Carr Rd hetween !"Iho' Rd S 10 I Illth A \L' SI and on or in the 'ieinit, of BCI1Sllll Rd S hetwccn SR 515 and S Puget Dr ill Renlon .... 20 I I) -2012 I'cderallaw 23 ,Inited Stales ('ode Section .JO'! governs usc of the dma you requested. I :nder this la\\. dala maintained t~)f pUTJliISCS oft!\-aluating potential highway safety enhancements: . slltlll nul he \lIhi('('llo discm'l'l:v or admiued into ~yid~nc~ in a fcdcrall)r state coun pWl..'ccding or cot1side,.cd.1hr plher ,"'rposes in w't)" (/c(ionfor titlmages arising from any occurrence at a location mentioned or addressed in such rcpons. surveys. schedules. lists. or data." I EmJllw.I'i.1 added. J The Washington State /)epanmenl of Tmnsponation (WSDOTi is releasing this data tn you with the understanding that ~llU \\ill nul usc lhis Jaw contrur: tll the reslrictions in Section 409. which means lOU \I ill nlH lI~C thb data in Jis1i:ov\.'ry \)r as \?vidence at trial in any action tlJr damages against the \\rSDOT. the Slale uf\\:-ashington. or an) other .iuri~dkti()n involved ill the locillions I1ll.!ntioneu in the data. If you should attcmrt to usc thi~ Jaw in an actil11l f()[ damages against \VSDO"I. tht' State 01-\Vashington. or any nthcr jurisdk:tion involycd in tbe [tK:ations mentioned in the Jal<l. these: r:nlitil,..'"s cxpn:~ ... ly reserve the right. und~r SCL"tion 409. to ohje(:1 Itl the liSt: orlhe dala. including an~ opinions drawn from Ihe data_ I 'i' 0 +-3 "f-St--f "f.. H If "C may pc of any fun her assistance'. pkasc conta,', m~sdf Or Me. Dan !lavis. (,(]~ion l)at2 td Anal,sis Supcnisur. at I :;(,0 I 570-245 I, or ,,-mail address davi,J<i \\SUol. \\a.gov / t 6 -;; ,~. ~ . ., oJ 1\1 ichael L. Bernard Collision !lala .-\nal) sl Statc\\ide Travel & Colii,ion Dala IWice Strategic Planning f)i, j"jl.)n ('ewe: '\aiisa Peshtal & Lauretta I.e\\. WSI)UI "'"nh\\esl Region I ~ 2. ~.!' ,.....-r;> \. loD I"(~ ;J.H" ~.H. Z.:l'{~ 1.3/ IDOT-RNB160J STATE OF WASHINGTON -DEPARTMEN'!' OF TRANSPORTATION DATE 02/04;'13 T R I P S SYSTEM TIME: 17;04;35 STATE HIGHWAY LOG PAGB :"473 SR 515 MAINLINE STATE ROUTE -SRSH COUNTY KING DOT DISTRICT 1 -------WIDTH Ah~ SURFACE INFORMATION------- :DIRECTION TO INVENTORY ;LEFT/RIGHT INDICATOR SRMP B ARM I FEATURE ID LRjDESCRIPTION 1_-_1- 4.41 4.38 4.53 4.50 !NTRSECTN a 5E 196TH 5T 4.60 4 .57 ":NTRSECTN B SE 1B4TH LN 4.75 4 . 7:2 INTRSECTN R 5E 182ND 5T 4.76 4.73 MIse FEATR L BUS PULLOUT 4.80 4.77 :::NTRSEcrN R SE 181ST 5T 4.83 4.80 Et-."D SU LN C TWO WAY TURN llA 4.8B 4.85 INTRSECTN L SE 180TH 8T ENT/EXIT R FIRE STATION 4.98 4.95 MP MARKER R 5 5.02 4.99 ENT/EXIT L SHOPPING CENTER 5.08 5.05 5.14 5.11 INTRSECTN L SE CARR RD :NTRSECTN R 5E 176TH 5T 5.22 5.19 :i:NTRSEC'TN L SE 174TH ST 5.29 5.26 END ST I l08TH AVE SE BEG ST I BENSON DR S INTRSECTN R BENSON RD 5.43 5.40 5.47 5.44 INTRSECTN L SE 172ND 5T 5.63 5.60 5.90 5.B7 6.00 5.97 MP MARKER R 6 6.03 6.00 INTRSECTN R S 27TH 5T 6.16 6.13 6.24 6.21 UXIl\G B PED XING BRDG NUM 515/010 6.26 6.23 -: N'I'RS E CTN R S 23RD 5T 6.32 6.29 6,37 6.34 INTRSECTN L S 21ST 5T INTRSECTN R PVT RD 6.50 6.4." INTERSECTION DETAIL ~---~-----TURN LANES---------- L NEAR R NEAR L FAR RFAR SRMP B ARM LGT WD LGT WD LGTWD LGT WD ------- 4.88 4.85 ,03 12 ,07 12 5.02 4..99 .03 11 5.14 5,11 .06 22 .07 21 5.29 5.26 ,03 11 6.03 6.00 .03 11 6.37 6.34 .03 12 .03 1:2 -BRIDGE DECREAS/DIV -UXING-NBR LFT RHT -XROAD-LNS SHD RDY SHD MEDIAN- OW TC :. o I W!S W!S W!S WD!S BR _1_1-_1-_1_1-_1- 2 2 CT Y PV Y CT N CT Y 2 2 CT SG Y PV SG Y PV Y 2 2 CT SG Y CT SG Y CT Y 2 2 CT SG Y 2 2 CT Y 2 2 2 2 CT Y 2 2 ST CT Y 2 2 CT SG Y CT SG Y 2 2 ------ACCELERATION LANES------ LEFT--L-CNTR R-CNTR RIGHT- LGT WD LGT WD LGT WD LGT WD .03 11 INCRES/UND! SPC ------CLASSIFICATIONS--- LFT RHT USE TOT LEGAL 5H::' RDY SHD LNS RDY MTCEICITYIST SPE.E:) TIS w/s W/5 w/s WID WID A SE NBR FC D :B R K T _1 __ 1-_1 __ -_1- C 49A C 11 60 4 01 1070 U:2 45 R P • C 50A C $S$ 60 4 01 1070 U2 45 R P • C 66A C 66 4. 01 1070 U2 45 R P • C 60A C 60 4 01 1070 U2 45 R P .. C 4.8A C 48 4. 01 1070 U2 45. R P C 48A C 48 4 01 1070 U2 35 R P .. C GOA C 60 4. 01 1070 U2 35 R P '* C 48A C 48 4. 01 1070 U2 35 R P '* C 60A C 50 4. 01 1070 U:2 35 R P '* C 4BA C 48 4 01 1070 U2 35 R P ." ,'11NCT T"lIH:t: I'I".IH·':N[/,':I-".:' i""" ,'" n"','/.f,1 .I\~' ~;N':I. li'll. IKII"r n':/L ,'I< I L" c ',,~" K''' I' e(c 4G BU'OR}: J("1 IIIE PAClFIC PL WYI; (,CNll ,]0 efl ",J AI'lI'.1l .)('11'0;1 I'A,'IIIf"' I:, ilYI' -01'11' J\~ ItW .Il"; 7",111 AVt, He 'lYi. ('PIIIIII < , ':' I '.1' li~f'll~r 1'"'1 "'AWl' ':l<lf'" I'If'Jo!lIl'i~1 1,1< " <, " (;'. ~FTI~ ",'. Nt'. WIN"t.HM~:l't. 11U '" (HI' A~ ''I',~ .H"I '"H ",I', >!IV I "olm ',1' <'I' ";1' ',J' q, "j !Uil~·H'1 :P',I.',lllJNlJ rr') ~2 1I~:t'\H~: ,1"1 ~:~ 'JC)I" c())NI)~;': '·')lIl'I.t:I"· 'V ,',1<11 I.t, I', Ila" ,'1' '.,' '11'11 ;~. 0', "1'01 I:; Jaceo 4J('{:O P.; co ! ~[CO ~,CGO ... hl CO 1 '1,(;'1 ~ HeO ; ~ I. 1: II' 1 ncn· ," IN I' 1401 t lHH } I ncr ?~I)(. 1.'11: ; .,.,' ) 3eee' I.(LI' ,.;. 1/ I'r-<II'; " ' n.OI:u J~O£O I,OLl; lUKe -' ~ II!'" ~·.CI.:I' "2"~ 1'11:11{' 1 ',oen 'I H~( llA:>bl) ON ACTUAL COUNT ~f)URr:J; Of" TRUC!! PJ;RCJ;NT"';F,;; OFFICER REPORTED COUiSIONS THAT OCCURRED ON STATE ROUTE 515 IMP 3.37· '.50) 1/1/2010· 12/31/2012 ... ,','filII.',' '.llll'\1111~('(JIII ~ll'nil\-III'} .'UI,\/).J/,l{ IV.\II/HI r'.\!II{,\/)!,\("Jllfl)',-!/1.1S11"!/,/',\'{"f- ." ~ I 11<1. t1 IX .. 1.\ f .I( "/111\ I (I/o: II-IH-II d:S H ,--I/,V,I,/ 'il loiS! ~ I ,( IR ,.j \ t ./1 N/.\/I/I III !,\.\ 1.\'1 (Ii 1"1'/1/\' IIII' J '_I f_~ COMP OIST OIR -"t"UK I MOST SEVERE I NIIM.'. DATE TIME INJURY TYPE fROM IMI fROM REFERENCE STATE MilE BLOCK INTERSECTING REf I~ REf POINT JURISDICTION ROUTE I POST NUMBER POINT POINT NAME ~~=--E~~~~ __ -r ______ +-~-+ __ ~ ____ +IEl~1:8~2~' 5:55PMIPo"lblelnju~ St.te Route 515 3.38 St.te Rout. 515 3.31 ~~~ __ ~~-+~~ ____ ~ ______ 1-__ 1-+-__ +-____ 11~338~2: 4:45PMI~"ibl~ury St.te Route 515 3.38 I E1382: 11, 21 201 4:09 PM INo Inju~ St.t. Rout. 515 3.38 I 3398149 4:00 PM INo Inju~ ".t. Rout. 515 3.'2 itat. Rout. 515 3.4: .,.t. Route 51 5 3." I 3257422 5:51 AM ~ 3/2: {2C 4:15 PM INo Injury , E089329 7:" AM !Po>sibie Inju~ ,St.te Rout. 515 3.46 , 3300911 111:10 AM ,No Inju~ ISt.t. Rout. 515 3.46 ISt.te Route i15 3.56 IState Rout. 515 3.62 1-1 1 3398: 11:48 PM INo I~i~t~.ne I 3384959 12:33 ISt.te Route 515 3.62 I 3338027 1:49 PM IPo>sible Iniu,,! ISt.te Route Jill: 3.62 I El15069 2;51 PM I Possible Inju,,! ISt.t. Rout. 515 3.62 I 3347054 10:55 AM I Died in Hospital ~::: SIS ~ 515 IState tout. SIS 3.62 ~~~-f~--~~~~r------1---+-r--+-----~1"~'21 ~ ~:~:~~INotniu"! I "06345 11/16/2012 12:37 PM INo tnju,,! ISt.te Route 515 3.62 IState Route SIS 3.62 IStat. Route 15 3.62 IState Route IS 3.6' I State Route as 3.62 IState Route i15 '.62 ,.. IState Route i1S 3.66 IStat. Rout. SIS 3.66 IState Rout. 515 3.70 ISt.te Route i15 3. IStat. Route 515 3.72 ,V>UU, 'U~IA S· bL fG- 1. f-b s Il... 1..(./':> rr.. ee;, 0 c S' ~. 11 I U I-;:. Sf. ~ ..-J {$2. -N. 21 101:,'= f+· (" 1"03838 11/5/2012 1:3::AMINotnju~ I E143099 1:0" AM INo tnju~ 1:5H p~ IPossible Inju,,! 338~ 3:33 PM INo Iniu~ I 3381218 11:30 AM INo Iniu~ I El43108 5:54 PM IPossible Iniu"! I E045465 {2010 3:07 PM IPossible Inju"! I El98625 ;:;;;;;;t 8:28 AM INo Inju~ 3381 16 I 1l/1 ~ ) Iniu~ 2781 j2 l2:13 I . 'Injury "03 17 1:53 PM INo Inju~ S I'~ -J .1-J S t" ~ ..... ,.A:cd s ,") -~ ,.1T.,!' I -:l. /,.... c ,CJ. e-....f.., ,.... v ~ ,"J ~c-/,f-J ffif'~~ 13 O. 6 0 102 o 1 12 10 11 101011 10 1010 1110 1010 l2 161013 1010 " " Stat. Rout. 515 3.86 El 76 "njury stot. Route 515 3.86 t'\, E117098 11:26 AM No Inju')' State Route 515 3.86 'V' 3205596 110,58. , Inju')' State Route lS 3.86 34082, 5/7/2010 2:10AM Nolnju,), State Route 515 3.95 3384435 8:30 PM No In)u')' State Route 515 3.98 3300541 8:07 PM No Inju')' State Route 515 3.98 ~ 10:38 , Inju')' State Route ;15 4.02 EOS0239 9:10 PM No Inju')' State Route 515 4.03 3381413 12/7/2010 9:02 PM No Inju')' State Rou'e 515 4.04 33111502 4:41 PM No Inju')' State Route 515 4.06 3381837 5/12/201: 4:45 PM No Inju')' State Route 515 4.07 E162032 3/31/201: 5:57 PM No Inju')' State Route 515 4.10 E079920 6:49 , Inju,), ~st~a~'R~oute~t5~"15~~~4.l.~'0 __ ~r-____ ~ __ -+~ __ +-____ +~~ 13 12 1:37 tlnju')' ~s,~a~'R~oute~t5~11!5~~~4 .. ~'0 __ ~r-____ ~ __ -+~ __ +-____ +~~)27 12:45 ,State Route ,515 4.10 1E183424 7/27/201: 6:46 AMINo Inju')' Istate Route 1515 4.10 I 3398659 111:07 AMINo In;u')' Istate Route 1515 4.10 I E074004 12:56 PMINo Inju')' Elsta~te'R~o,uu~te~I~51'7-!5-+~4~.'0~ __ ~ ______ +-~-+ __ 1-____ +I~~ 4:49 PMINo Inju')' Ist.te Route 1515 4.10 I EJ 8131201: 3:43 PM INa Inju')' Istate Route 1515 4.10 I EOS0146 4. 7:20 I "nju')' Istate Route 1515 4.10 I El84011 1:04 "nju')' Istat. Route 15 _ 4:10 I E19493, /27/20 :13~lnju')' Istate Route 1515 4.10 t 7<; ~ I E093860 /27/201 3:50 I "nju')' Istate Route 1515 4.10 -~ I E093274 12:04. E,sta~te'R~oure~~15~-r74 .. 1~0 __ ~ ______ ~ __ ~~ __ +-____ ~IE~~l 6:48 ,'nju,), Istot. Route 1515 4.10 I Ei44826 l1:lOAMINo Inju')' Istate Route 1515 4.10 I E157194 "nju')' 15tat. Rout. 1515 4.10 I ~ ,'nju')' Istat. Rout. 1515 4.10 I E164931 ,'nju')' !5t.t. Route '515 4.10 I E167486 4:01 PM INo Inju')' 15t.te Rout. i515 4.10 I El 8547 8:OS ,'nju,), IState Route !515 4.10 I EOS1345 , Inju')' Istate Route 1515 4.10 3378509 E/l/201 7:25 AM INa Inju')' ISt.te Rout. 1515 4.10 I 3398328 7:03 AM INo Inju')' IState Route 15 4. I EHlO988 6:40 PM INa Inju,), , U" .2 1 ; 1 1 o " 2 12 ,2 12 12 11 12 12 13 State Route 515 4.10 3522376 6/1/2012 5:54AM No Injury o 0 2 --SiS 4.10 3378W2 2/26/2012 1:40PM Evident Injury 2 2 State Route SIS 4.10 E093858 2/25/2011 3:53 PM No Injury 002 State Roule 515 4.10 E044179 2/15/2010 5:54PM Possible Injury 102 St.ate Route 515 4.10 -f055742 6/9/2010 2:50AM No I~jury o 0 2 State Route 515 -=11 £106179 5/23/2011 4:39PM Possible Injury 102 State Route 515 4.13 E074682 11/1/2010 7:15 PM No Injury 002 State Route 515 4.14 E128162 10/l/2011 2:49 PM No Injury 002 State Route 515 4.1S E045342 3/10/2010 5:34 PM No Injury o 0 2 State Route SIS 4.16 E164683 4/15/2012 2:30 PM No Injury o 0 2 State Route 515 4.18 E118023 7/22/2011 3:56 PM Evident Injury 102 State Route 515 4.18 E064946 8/26/2010 3:41 PM Possibte Injury 1 0 2 State Route 515 4.19 E084081 12/20/2010 6:19 PM Possible Injury 1 0 3 State Route SIS 4.20 E218618 12/30/2012 12:26 PM Possible Injury 102 State Route 515 4.23 E166664 4/26/2012 10:08 PM Unknown 001 State Route 515 4.36 E072614 10/20/2010 1:36PM POssible Injury 202 State Route 515 4.38 E052086 5/13/2010 1:55AM Possible Injury 101 State Route SIS 4.44 E092676 2/22/2011 10:44 PM No Injury 002 '1. II W5DOT • COLLISION DATA 10/11/13 15 of 21 Rfp9ttrd cpUWpm Chat qcgtUfd on SIpk Routr SJ51mq .... 5J to fi.ZSJ frgm Sf JMh Sf to Sl3rd Sf. on Of III rhf IIIdnlhr D'S{ (WRIt bftwem To/bot Rd S to lJ§1h A .... Sf lIIIdJiMmo Rd S bctwnn 58 ill pnd S PII!Kt Dr JII Rmfpr! .lQID -zqu UNDER 11 !JNIT£D1I~In {QQl :.H~~JWH~""~.~"'~OT8E ug~ IfW LHSWVERY QfI' AS EVW(-'Y.U ~I_t!fIAL IN ANY ACIJON FOR lMMAGES AGAINST tHf WSDQT. ORANYJIJIII,SD!CTf(W tNVDf.tnlHN mf Do41A PRIMARY MILE BLOCK , , TRAfFICWAY POST I NUj,\BE' ,,, 't .. , ""'" S1S '.sa """ ""'" S1S .... " .. , Ro,,, .. S~" '"" .. 5." S. 5'''' ""'to 51< 5"" '""" 5)< '''-'''0.'' 5IS 5.1< Prrp,lIre-d by; WSOOT/STCDO/CDAB/MD lO/08/B C' 'J INTERSECTING TRAFFICWAY I COM? 0151 DIR FROM fROM REf 'EF REfERENCE POINT REPORT I PO'NT Mlorn POtNT NAME I NUM'" ~ I EllS70J l.EQ9.J "" ~ I''''' I "697" 12638' "'''''' 12 ... EO'~ E204<09 I E202". I "19120 MOST SEVERE DATI TIME INJURY TYPE , , , "'J'" 3 07/1>/' '''0' ° 0 , '~ 0 losll' I'''''' , o 0 , , , I" , ""." 12/ 12,,, PM No I,;.", ~ 0 , , Nol 0 111/0 r;'" 0 , 103/: ffiik ,,"",. NO:"'~ D 0 08/04. ",. , I,;.", 0 I 61 of 90 Reportrd collisions ctrcrt mwrcd Oft Statr 8oIItI! 515 (mp 4.5J to 6.2BI from Sf JMh Sf to s 23rd $(' 9ft qr in thf yIdnity p' Sf Ccur Btl bttwnn TpIbqt Btl s f9 J1Ah All! SEaM 8mwq Rd s btfwua $B 515 pad S "., Dr" In Radw! •. .2flJq -29J2 V!:!!Qf,ll n IJIIItT{D STATES CQO£ . 5ECT!0ftI49? THIS LM T A CANHO! IE USED IN OIscovPl'Y ClfI AS MOiNq AT TJUAL IN ANY ACTION FOR QoW.!G{S AGAINST THE WSDQr Ott ANY J!JffISlJICOON IIIIVIXV£DIN THfllollTA PRIMARY MILE JURISDICTION TRAffICWAY POST 1m 1m 45' .. ," """" m I 15 454 , .. " -" 15 "'''-" m 4.80 "",Roo" * 4." i , .. " Rooto m "'" 'D.," m 4.88 4." ill ~red by: WSOOT/STCDO/COAB/M8 10/08/13 0<" IC:P ''''M FROM BLOCK INTERSECTING '" Ref REFERENCE POINT NU .... E. PO'"' M", FT PO'"' NAME REPORT MOST SEVERE IN~R DATE TIME INJURY TYPE I,,", If.T , , 1 .. 56 ... ' .,. '21/10 0 0 1 IE .. "" '24/: 2 0 2 is ' .'" 0 0 2 , 2 , 103/30, Eli loa 1:05 P. No ,,"'" 0 0 ~;I ; "'I'''' 3 0 2 11090' !"'S81 , "j'" 0 ~ ~ , 0 2 , 2:45 PMINo' ~IT """'" 0 0 2 ~: , ..... " 1109115' "",. No";..,,, 0 0 2 ~ 8:15'. ND :~'''' 0 0 2 , 0 3 5S 0190