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HomeMy WebLinkAboutLUA-07-021_MiscHAZEN RESERVOIR WETLAND AND STREAM RECONNAISSANCE REpORT City of Renton February 2007 ~prepared by RH2 Engineering, Bothell, WashIngton I City of Renton Hazen Reservoir Wetland & Stream Reconnaissance Report Prepared by RH2 Engineering, Inc. February 9, 2007 Project Description The City of Renton is proposing to construct a second water reservoir in the City's 565 Pressure Zone. The proposed reservoir is intended to ensure sufficient storage for normal and emergency uses and allow the existing reservoir to be taken out of service for maintenance. The proposed reservoir will be constructed on City-owned property located south of Sunset Boulevard and west of 142"d Avenue SE. Site Description The 565 Reservoir project site (Site) encompasses approximately 8.7 acres (per survey data) and is accessed via SE 112" Street, which is a private gravel drive (T23N, R5E, Section 3 SE 'I. SW 'I. WM). The parcel number is 0323059061. The Site is largely undeveloped, with the exception of some unimproved trails in the southern portion and some minor residential activity along the borders of the Site. Adjacent properties consist of Hazen High School to the south, an athletic field to the west, single-family homes to the cast and Sunset Highway to the north. \Vithin the northern third of the site, Honey Creek flows from east to west and contains associated riparian wetland habitat. Wetland Habitat RH2's Wetland Scienrist performed a site investigation on November 9, 2006. Wetland reconnaissance and classification of identified wetlands was performed consistent with the Washington Department of Ecology'S lY'aJhiliglon Stat, Wetland Identification and Delineation Manual (McMillan, 1997) and the Washington .flale Wetland Rating System for Western Washingtoll (Hruby, 2004). Wetland data sheets have been included as Appendix A. There were no wetlands identified witl1in the proposed construction limits of the project. The nearest wetland habitat was identified in association with Honey Creek, approximately 400 feet north of the proposed reservoir construction limits (see Figure 1). Wetlands were classified as riparian flow-through, Category II wetlands and were rated as part of a larger, contiguous wetland complex that crosses under 1420d Avenue SE. This larger wetland was previously classified by King County (KC) as a Category II wetland (KC GIS data, 2006). During the pre-design site survey (R.W. Beck, 2004), wetland delineation flagging was identified for a portion of the wetland. During the site visit, RH2 confirmed that this flagging is consistent with the current location of the wetland boundary. RH2 installed pink wire stake flagging to mark the southern boundary of the wetland, although a full delineation was not performed. Within city limits, Category II wetland habitat requires a 50-foot buffer. 1:\dala\REN\ lOS-049\Permitting\Hazen Critical Area~ R<CC(Jn FEB07.JlJC 2/9/200712:50:09 PM City of Renton Hazen Reservoir Wetland & Stream Reconnaissance Report Page 2 Streams RH2's Aquatic and Fishery Scientist performed a site investigation on November 9, 2006. There were no streams identified within the proposed construction limits of the project. Honey Creek is the sole stream on the project site and is located approximately 400 feet north of the proposed reservoir construction limits (see Figure 1). Honey Creek has been classified as a Class 4 stream at this location per the Renton Municipal Code (Figure 4-3-0S0Q4). A delineation of the Ordinary High Water Mark (OHWlvI) was performed during the pre-design site survey (R.W. Beck, 2004), and the OHWM flagging was located along the southern bank of the creek. The surveyed delineation was conflrmed to be an accurate representation of the current OH\V1v11ocation of Honey Creek. The Class 4 designation of Honey Creek at this location is considered appropriate. The stream channel generally consists of muddy substrate or is vegetated, suggesting that flow is seasonal. The stream channel has very poor to no salmonid habitat value at this location. Additionally, Honey Creek continues downstream through a series of significant culverts that would impede the migration of anadromous salmonids upstream to this location. Class 4 streams require a 35-foot buffer within city limits. Sensitive Areas Protection during Construction Prior to the start of clearing and grading at the project site, appropriate Temporary Erosion and Sediment Control (I'ESC) measures will be employed to protect surrounding forested buffers. This project requires a Construction Stolmwatcr Pollution Prevention Plan (CSWPPP), which will be finalized prior to construction, along \,virh an application for compliance to the Construction Stormwater General Permit. The area of nighest concern is the Honey Creek stream corridor and associated wetlands. This area is separated from the project site by approximately 400 feet of naturally forested buffer with permeable forest duff soil (R.W. Beck 2004), making it extremely unlikely that surface water from the construction site could travel to, and adversely impact, the sensitive areas before inftltrating. Trenching will occur to the northwest of the reservoir site for the installation of the water main pipeline. Construction activities for this pipeline installation will remain well outside the Honey Creek stream and wetland buffers with tne closest point being approximately 200 feet from the sensitive areas (see Figure 1). Appropriate TESC measures will be installed along the pipeline trenching and the areas impacted during installation will be stabilized at project completion. Stormwater and Reservoir Overflow Management The completed site's stormwater will bc routed through a detention pond, which discharges to a level-spreader, located approximately 400 feet upslope of the Honey Creek stream corridor. As indicated above, the area between the level-spreader and the stream corridor is naturally forested with associated forest duff soils that have an adequate capacity for infiltration. The detention pond has also been designed and appropriately sized to function as an emergency reservoir overflow facility. Site stormwater analysis and facilities designs were completed using King County Runoff Time Series Program (KCRTS) and King County .J1Ilf'1'" Water Design Manual, 2005 edition (KCSWDM). For detailed j:\data\REN\lOS-049\Permitting\Ha?en Critical Are,l~ Rl'U}Q H:R07,Joc 2/9/200712:50:09 PM City of Renton Hazen Reservoir Wetland & Stream Reconnaissance Report Page 3 ------------------------------- design specifications, please refer to the Hazen Reservoir Technical Information Report prepared by RH2 Engineering (2007). Conclusions There are no sensitive areas (streams, wetlands or buffers) located witbin the Hazen Reservoir project construction limits. The only sensitive areas identified near the project site are located approximately 400 feet north of the proposed construction activities. If stormwater management procedures are carried out as directed in the CSWPPP and the Hazen Reservoir Technical Information Report, it is anticipated that this project will have no negative impacts on the sensitive areas associated with the Honey Creek stream corridor. References Beck, R.W. Prepared for City of Renton. Novcmber 2004. Draft 565 Zone Reservoir Pred,sign Report. Hruby, T. Washington State Department of Ecology. August 2004. Wasbington State Wet/and Rating System for Western lf7asbington -R"'iJed. Washington State Department of Ecology, Olympia, WA. Publication No. 04-06-025. King County GIS Center. April 2005. Published Geographic Information Systems (GIS) data. Obtained May 2005. McMillan, Andy M. Washington State Department of Ecology. March 1997. Washington State Wetlond Identification and Delineation Manual Washington State Department of Ecology, Olympia, WA. Publication No. 94-96. RH2 Engineering, Inc. Prepared for City of Renton. Winter 2007. Hazen Reservoir Technical Information Report. J:\data\REN\ lOS-049\Permitcing\Ha7.en Critical Area~ r(<,con I· r.B07 ,due 2/9/200712:50:09 PM ~ I i I i ,,,,",,, ~lIH ",,,I I i I "-~"--'!".-~ " t APPENDIXA WETLAND DATA SHEETS .. DATA FORM 1 (Revised) Routine Wetland Determination (WA State Wetland Delineation Manual or 1987 C W tI dD tin • M ual) orps ean e eation an , ProjectlSite: ~~rdi) 113W\ \'t~trJO ir- Applicant/owner: cd, ut rtvrJ-o Y1 , .. !,' 'Inves!igator(s): d\illJ pe,-\hb~n~, rh2 tvlqlyh'c l 111(1 Date: 1 \ /'1 loro County: Il..l v:J State: w~; ~ Ie SfTlR:," 2.3 S -Sf: Do Nonna] Circumstanct!s exist on the site?',J 0~ no Community ID:fbl1'st~c\ -fYlil<;-t.f Is the site significantly disturbed (atypical situation)? yes ~ Transect ID: - Is the area a potential Problem AIea? yes n Plot ID: if '"'I Explanation of atypical or problem area: VEGETATION (For strata. indicate T = tree; S = shrub; H = herb; V = vine) Dorrtinant Plant SpeCies Stratum % cover Indicator .Dorrtinant Plant Soecies Stratum % cover Indicator h~~r c'lnim'\1Am s ,FAC- Ac~r rt1a CrQ_pliil\\,{m T 'fAN ft'~lAdOhlt~;) i'l1t~zitSii '\ fACIA o ~!IY\ leli d' ~erasi {u r(I1i s S fACIA f~\\~1~nV\m l11\tnH"-1Yl f JAt\..\ HYDROPHYTICVEGETATION INDICATORS: ' , % of dominants OBL, FACW, & PAC 1.0°/. .. Check all indicators lbat apply & explain below: Visual observation of plant species growing io Physiological/reproductive adaptations -- areas of prolonged inundationlsaturatio~ --Wetland plant database -- MOIphological adaptations --Personal knowledge of regional plant communities -- Technical Literature Other (explain) Hydrophytlc vegetation present? yes ® Rationale for decisionlRemarks,: a" 30-foo-\-raai~~ 4H~3\ rIot II; fAC-ordflrer i\\~iQ<1"\uv-, ()omil\o1rrt v~Jtt.mo~ obStt\/~ N\'IVilll a , , HYD~y Is it the growing season? yes ~., WaterMarks: yes ® Sediment D,epcisits:, yei ® On , Basedon: , soil temp (reeon! !=p' .) . Drift Lines: yes® Drainage Patterns: yei@, J oilier (~J<1llain)'th,~ 10, SOil S\l Nfl' Dept of inundation: ~~jnches \ Oxidized Root (live ro~ lJ>cal, Soil Survey: yes ® Channels <12 in. yes no Depth to tree water In pit: -=-incbes , PAC Neutral: iv/es ~ Water-stained Leaves yes@ Depth to saturated soil: -=-inches o , 4" Vlelllati ~ Check all thai,apply & eXplainbe)ow: Other (expIlIin): Stream,Lakeorgageda~ -- Aerial photograpbs: Other: WetlaildhydrolOlY present?· . yes ~ . ~;ti~t~~grirs&~&1: iYI(\i~aturS' l II \~"'J\()5\ o~~~m~ 'Ih YiCini~ of tt&\-f\at, , , " . SOILS Map Uni~Name Alt!txwooJ amell, ,\\:lVldr IUd 1\1, ~-\sol" (Series & Phase) v' I Taxonomy (subgroup) D1~C D\lroenr~pt Profile Description Depth Horizon Matrix color Mottle colors Mottle abundance (inches) (Munsell (Munsell size & contrast moist) moist) 0-I 'J --- HCn 'J " IO\~ 311--- Drainage Class MoA~'fM~\t 'Nt \ \ Field observations conflrm (y ~ No mapped type? Texture, concretions, Drawing of soil structure, etc, profIle (match descriQtion) Jt~ul'Aio~in~ UV3H\ ic .. ''i~''~:' 3rml\1 SJ~~I \OJI'V\ .... ~- 0." tI , , • /.1· r"_ ..... : -, . l .-~ ..... ' 'I' . ,til '. - . Hydric Soil Indicators: (check all that apply) __ Histosol __ Matrix chroma::; 2 with mottles _. _ Histic Epipedon __ Mg or Fe Concretions ;., __ Sulfidic Odor __ High Organic Content in Surface Layer of San'ay Soils " _. _ Aquic Moisture Regime __ Organic Streaking in Sandy Soils __ Reducing Conditions __ Listed on NationallLocal Hydric Soils List Gleyed or Low-Chroma (= 1) matrix Other (explain in remarks) Hydric soils presCD:t? yes ® ~I~~~:r:~o~~~~~ <iYlc\ is not hidr1C. lio ~\li~el\e~ o~ ~·(d Ii t GUll i\'\Jlc~tv\'f;' were, o~ex'l~~, , .... Wetland Determination (circle) , Hydropbytic vegetation present? yes @ ® HiMe soils preseiJt? yes ® Is the sampling point yes Wetland. hydrology present?· . . yes (ll{;) , within a\vetJaDd? .. , .. . "' .. -. . ~~n~~:r;~s~ ~it ~a~ \Qtahd <1pyroxiV1i<lh;\r i'5-~t~t Y10 r+h orl10\')e1 CHtk Hl~ 'N1)\J.\d ~t COnSl ~tredlJJt\\<l'rt4 d'll~ lo\' .fIT e a rill ~wtf -er ?~\' Rtl1rol'l_ ,r-,hm ICI ~d \ eoq ~, , ,. , .' " /, ' ' NOTES: .. ;; ". . .; Rev,ised 4/97 ,'; ','. . , "',,: , . ,J . DATA FORM 1 (Revised) Routine Wetland Determina.tion (W A State Wetland Delineation Manual or 1987 C ) orps Wetland Delineation Manual .. Project/Site: r~nttl'\ ~an\\ r-eStNO·,r Applicant/owner: ~;1 ~ ~~ fee \~ 11 . f:, • investigator(s): a\I~\a pk\tibQ\1f J r'rJl. ~~ql'llLenY!"1 Date: 1\/9/0 10 County: Ki I1j State: WA ~~ SfI'IR: 3;2.3 5-S'E Do Normal CircumstanceS exist on the site? J ~es no Community !D: "\b 'r~STt~ -'rIl iX e~ Is the site significantly disturbed (atypical situation)? yes no Transect!D: _ Is the area a potential Problem Area? yes no Plot!D: 1f #"7- Explanation of atypical or problem area: VEGETATION (For strata, indicate T -tree; S ~ shrub; H ~ herb; V ~ vine) Dominant Plant SpeCies Stratum % cover Indicator Dominant Plant Species Stratum % cover Indicator Mtr ~\\tiYlaTu.1'V\ S fl\~- RlAb\.\S ~~d·dbi\i~ S fA~T Ac~r Wl3CI1)pVtll\\.tWli' T fACIA . fO\ls\ic~um 1'I1IA.l1itum r fAe\),; .. I • .. HYDROPHYTIC VEGETATION INDICATORS: .kl)~l~af. Vl'\~~f., roY]~t~s canof~ CQV~rJ b~t .. % of dominants OBL. FACW. & PAC 50 oto Y\ ~fH(Wl~ S tft~tl'\ v~l+n 30-etoF teST ,. Y\1· . Check all indicators that apply & explain below: Visual observation of plant species growing in / Physiologica!lreproductive adaptations ../' areas of prolonged inundntionlsaturatioJ.l --Wetland plant database Morphological adaptations --Personal knowledge of regional plant communities -- Technical Literature Other (explain) Hydrophyticvegellilion present? CJ!!). no . .. . .. . . .. ;~;nl=[fo~~1~;~1;0V1 &~tro\\\1JiV1j iestYe(x~ SOO/1l fA~lr ~tit~r.JaC\\-hp~lh~ro-'O~'C'\Jf', .1;moY1' JIV1,I'i~:rtO~ W€rp· obs~ e SlWT> 0 1'+ orYIihJItlCe . iI1e~~ ~V . HYbRf'tJ .Any . I' I· Is it the growing season? yes @ Water Marks: yes ~ Sediment pepcisits: yes ® on . . Bll.\edon: $oillernp (reoord temp· ) . ../ otber(exillain) l(iri~ ('n. ~ol\ \1J.f\Je'i Drift Linell: yes(§) Drainage Patterns: yes ~. Dept of inundation: .....:::.... ;,Icbes • Oxidized Root (live ro~ ~dSOi! ~~tr~~. ~~L Channels <12 in.ves no.. IpI l.l.o.lY) hhd\C '"V Depth to free water in pit: ....Lincbes . . FACNeutr~a'n yes(§) IlWater-sl'ained Leaves yes(® Depth to $aturated soil: ~inches O:2"neCl i'lt. Check all tb~( apply & e~ph,;n below: Otl1~r (expllrln): Stream. Lalre or gage data; --Aerial photographs: . Other: Wetland bydroloey present? . yes DO 3aa~~t~6~drht-~twrlh Ob8tillt~ v'li1hin\lrst Iz-·mcht3 ~ -hst flor. . . . . . son.s Map Unit Name &ha\cat"" M\.\~k (Series & Phase) Taxonom (sub ou) Ttrril\ Med-ISaDrlsts Proffie Description Depth Horizon Matrix oolor Mottle colors (incbes) (Munsell (Munsell moist) moist) 0-1 'J -- . \-12" 11l1R. S" - . Hydric Soil Indicators: (check all tbat apply) __ Histosol __ Histic Epipedon __ Sulfidic Odor .. __ Aquic Moisture Regime __ Reducing Conditions --L. Gleyed or Low-Chroma (=1) matrix Hydric soils present? yes no~ Drainage Class Ytq Poorl1 Field observations confirm Q'~~ No rna ed e? Mottle abundance Texture, concretions, Drawing of soil size & contrast strUcture, etc. profile (match descrilltion) -d~CIlM~OS'lVli O~orYl\C Sal1dllV\lAt~IIOJVVl ' , .... ~'.4~, r -<' I" " "r· Vb "/ .l..1111 __ Matrix chroma::; 2 with mottles __ Mg or Fe Concretions __ High Organic Content in Surface Layer of Sandy Soils __ Organic Streaking in Sandy Soils ~ Listed on NationalJLocal Hydric Soils List Other (explain in remarks) S;~O;~~~1d~ifjfe~~frrVY\t~ tlVl~IS tJ\dric,. fnY'l\a\~Seco~J4~ \Y'\~ita+orS' Ot hid ric., .10\\:; 1J'{~'(e olo~et\lt~. . . Wetland Determination (circle) . Hydropbytic vegetation present? ~ no Hy!!i1c soils present? . yes no Is the sampling point Gili no Wetland hydrology present? . , . yes· no . within a'wetlafld? .. ' ..... -. . RaiioDali!IRemiirkSf" .' .. '. . \a:~in~t ihai~3hrs Ob~-e'/\le~ for all cDYV1toneV1}s:·.l{S'r·fi~ \o~q+ed \"l'I1hro +No ~e~i' of ikYler tf.H\qI'lXV'lQIA.\~ be t~VJ~iAfxe~n~a\l4V) wti\d I14. .. _. '. . ... .--'. , , ., ..... "'~. I' .. Rewsed4l9i " ;" 'T\ • ;{ :'; DRAlfT WETLA1>m RATING FORM -'WESTERN WASHINGTON Name of wetland (ifknown): \\lHIJ R!~trJvIY J'de-Jb\U:i tf{t\( Ripd\1~V\ "~~\bV14S \ \ Location: SEC: _ TWNSHP: _ HNGE: _ (attach map with outline of wetland to rating fonn) Person(s) Rating Wetland: Mie~ P{\\iWnI11'1 Affiliation: R~J (%\,f~" ,c,Date of silevisit; Jlh/o('" DRAFT SVIvIMARY OF RATING Category based on FUNCTIONS prOvided by wetland L-u.Lm rv_ Category I = Score >70 Category II = Score 51-69 Category ill = Score 30~50 CatelmIY IV = Score < 30 Score for Water Quality Functions Score for Hydrologic FunctiOJlll Score for Habitat Functions TOTAL score for functions Category based on SPECIAL CHARACTERISTICS of wetland 1_ IL-Does not ApplyL to 1& 11 55 Final Category (choose t.he "highest" category from above) EI Check the appropriate type and class of wetland being rated. Wetland Rnting Form -weste-l1l Washingion AuguS12004 Western Washington lVetland Classification Key Wetland Name: 'XStY\juil'~itt -\-NIH ~f{ l :>\. l\iM W~\t\\1~::: AUID#: \ 11191010 , ' I) Water levels in AU usually controlled by lides ~ go (0 2 Yes -Tidal Fdnge 2) ~ography is flat and precipitation is only sOllrce (>90%) of waler to the AU ~got03 Yes-Flat 3) AU is contiguous ,vitll >8 ha open waler, and water is deeper than 2 mover 30% of open water area @-gO to 4 Yes -Lacustrine Fringe . 4) ~ water is <8 ha and >2 m deep, but AU is a fringe narrOwer than V, the radius of open water e: go to 5 Yes ~ Lacustrine Fringe . 5) ~rflow in AU is unidirectional on a slope, water is not impounded in the AU ~ go to 6 Yes -Slope 6) AU is located in a ~phic valley with siream or river in the middle No-got09 ~goto7 7) Have data showing area flooded more than once every 2 yrs.; or indicators offIooding are present: o Scour marks common o .-Recent sediment dePosition g Vegetation that is damaged or ben I in one direction o Soils have alternating deposits 8'" Vegetation along bank edge has flood marks No for all indicators -go to 9 8) Flood waters retained rN.)':;)Riverine Flow-through '--reS' -Rh'erine Impounding o Depression in flOOdplain o Constricted. outlet o Pernlanent water ®]!Ir any indicator -go to 8 \I) Has surface water outfIow-Depressional Outflow Has no surface outflow -Deprcssional.C1osed J Procedures -Lowlands W W A Pan 2, Augusl 1999 DntasheelS R R i.l Area the riverine wetland that can trap R sediments during a flooding event: Depressions cover >3/4 area of wetland points = 8 Depressions cover> II2 area ofwet1and points = 4 Depressions present but cover < 112 area of wetland points '" 2 R 1.2 of the vegetation the Forest or shrub > 213 the area of the wetland Forest or shrub > 113 area of the wetland Ungrazed, emergent plants > 2/3 8l'ea of wetland Ungrazed emergent plants> 113 area of wetland < 113 =0 points = 8 points =6 points = 6 points"':! =0 R. Add the points in the boxes above R R 2. Does the wetland haVe the opportunity to improve water quality? (seep. 53) Answer YES if you know or believe there are pollutants in groundwater or surface water coming into the wetland that would otherwise reduce water quality in streams,' lakes or groundwater downgrailient from the wetland? Note Which o/the follawirzg cOllditiOlzsprovide the sources o/pol/wants. R -Grazing in the wetland or within 150ft -Untreated stonnwater discharges to Wetland -Tilled fields or orchards within 150 feet of wetland . - A stieani o:rculvert discharges into wetland that drains. developed areas, residential areas, farmed fields, roads, or clear-cut IOgglng ~ Residential, urban areas, golf courses are within IsOfiofwetland -The river or stieamlinked to the wetland has a contributing basmwhere human. activities have raised levels of sediment, toxic compounds or rrutrfents in the river water above standards for miter quality '. isl NO is1 ...,,~ __ Water Quality Functions Multiply $e score from R 1 by R 2 . table 1 Comments Wetland Rnting Form -western Washlngton 7 August 2004 multiplier 2.0 R of the overbank storage R R Estimate the average width of the wetland perpendicul«r to the direction of the flow «lIIi the width of the stream or river clumnel (distance between banks). Calculate the ratio: (width ofwetlalld)/(width ojstream). If the ratio is more than 20 points = 9 If the ratio is between 10 -20 points = 6 If the ratio is 5-<10 points = 4 If the ratio is 1-<5 points = 2 <1 of vegetation during Treat woody debris as 'Jorest or shrub ". Choose the points app"opriate for the best de.Ycription. Forest or shrub for >1/3 area OR Emergent plants> 213 area Forest or shrub f<iT> 1I10ilrea OR Emergent plants> 1/3 ares points=7 points =4 the points in the boxes above R R 4. Does the wetland have the opportnnity to reduce flooding and erosion? R (seep. 57) Answer YES if the wetland is in a location in the watershed where the flood storage, or reduction in water velocity, it pr~Vid~ helps protect downstream property and aquatic resources from flooding or excessive andlor erosive flows. Not7.hich of the folloWing conditions apply. --There are human structures and activities downstream (roads, buildings, bridges, farms) that can be damaged by flooding. --There are natural resources downStream (e.g. salmon 1'Imds) that can be damaged by flooding -Other _______ ~ ____ ~ _____ ___ (Answer NO if the majO/' sow'ce of water to the wetland is controlled by a resel1 l oir Comments wetland is tidalfi'inge along the sides of a dike) multiplier is 2 NO multiplier is 1 TOTAL -Hydrologic Functions Multiply the score from R 3 R4 Add score to table Oil p. 1 Wetlond Ratmg Form -westem Washington s August 2004 7 multiplier 2.. \~ H 1. Does the wetland have the potential to provide habitat for many H 1.1 (see p. 72) Check the types a/vegetation classes present (as defined by Cawardin) if the class covers more than 10% of the area of the wet/and or ;4 acre. __ Aquatic bed Emergent plants ' 7 Scrub/shrub (areas where shrubs have >30% cover) /Forested (areas where trees have> 30% cover) -./'Forested areas have 3 out of 5 strata (canopy, sub-canopy, shrubs, herbaceous, moss/ground-cover) , Add the number of vegetation types that qualify. If you have: H 1.2. p.73) 4 types or more 3 types 2 types points =4 points =2 points = 1 Check types of water regimes (hydro periods) present within the wetland. The water regime has to cover more than 10% of the wetland or ;4 acre to ciJunt. (see text for descriptions of hydro periods) ,./ Permanently flooded or inundated /Seasonally flooded or inundated __ OccaSionally flooded or inundated __ Saturated only 4 or more types present 3 types present 2 types present __ Permanently flowing stream or river in, or adjacent to, the wetland ./ Seasonally flowing stream in, or adjacent to, the wetland __ Lake-fringe wetland = 2 points __ Freshlvater tidal wetland = 2 points H 1.3. (see p. 75) , points = 3 points = 2 point = 1 Count the nUmber species in the wetland that cover at least 10 ft2. (different patches of the same specil!s C,an be combined to meet the size threshold) You do not have to name the species. Do not include Eurasian Milfoil, reed canarygrass, pUlp/e loosestrife, Canadian Thistle ' If you counted: List species below ifyoll wallt to: bio\\~a~ lVId?\t 'rli\\uvon 2'S\'n 0 l'1~e~~ '1\ V't \"i\\~\ '" ' (\OU~ '~( S\"l~n\f~m Wetland Rating Fornl-western Washington 13 > 19 species 5 -19 species < 5 species points =2 points = 1 points = 0 August 2004 H 1.4. Interspersion of habitats (seep. 76) Decide from the diagrams below whether interspersion between types of vegetation (described in H 1.1), or vegetation types and unvegetated areas (can include open water or mudflats) is high, medium, low, or none. None = 0 points Low = 1 point Moderate = 2.points ~ [riparian braided channels] High = 3 points NOTE: If you. have four or more vegetation types or three vegetation types and 0 water the ratin is always "bi ". H 1.5. Special Habitat Features: (seep. 77) Check the habitat features that are present ill the wetland. The number of checks is the number of points you put illto the next column. . --.LLarge, downed, woody debris..rothin the wetland (>4in. diameter and 6 ft long). __ Standing snags (diameter at the bottom> 4 inches) in the wetland __ Undercut banks are present fot at least 6.6 ft (2m) andlor overhanging vegetation extends at least 3.3 ft (1m) over a stream for. at least 33 ft (10m) __ Stable steep banks of fine material that might be used by beaver or muskrat for deuning (> 30degree slope) OR signs of recent beaver activity are present . ~At least ':4 acre of thin-stemmed persistent vegetation or woody branches are present in areas that are permanently or seasonally inundated.(structuresfor.egg~laJ'ing by amphibians) ./ Invasive plants cover less than 25% of the wetland area in each stratum of plants Comments Wetland Rating F onn -western Washington H 1. TOTAL Score -potential for providing habitat Add the scores ill the column above 14 August 2004 \ \ H 2. Does the wetland have the opportunity to provide habitat for many species? I::'i',\';'> H 2.1 Buffers (seep. 80) Choose the description that best represents condition of buffer of wetland. The highest scoring criterion that applies to the wetland is 10 be used in the rating. See text for definition of "undisturbed. " -100 m (330ft) of relatively undisturbed vegetated areas, rocky areas, or open water >95% of circumference. No developed areas within undisturbed part of buffer. (relatively undisturbed also means no-grazing) Points '" 5 -100 m (330 ft) of relatively undisturbed vegetated areas, rocky areas, or open water > 50% circumference. Points = 4 -50 m (170ft) of relatively tmdisturbed vegetated areas, rocky areas, or open water >95% circumference. Points =4 -100 m (330ft) of relatively undisturbed vegetated areas, rocky areas, or open water /> 25% circumfereoce, . Points = 3 3 -50 m (170ft) of relatively undisturbed vegetated areas, rocky areas, or open water for> 50% circumference. Points = 3 Ifbnffer does not meet any of the criteria above -No paved areas (except paved trails) or buildings within 25 m (80ft) ofwet1and> 95%circumfereoce. Light to moderate grazing, or lawns are OK. Points = 2 -No paved areas or buildings within 50m of wetland for >50% circumference.. . Light to moderate grazing, or lawns are OK. . Points = 2 -Heavy grazing in buffet. . Points = 1 -Vegetated buffers are <2m wide (6.6ft) for more than .. 95% of the circumference . (e.g. tilled fields, paving, basalt bedrock extendto edge of wetland Points = O. -Buffer does not meet any of the criteria above. Points = 1 H 2.2 Corridors and ConnectiOns (seep. 81) H 2.2.1 Is the wetlandpart of a:relatively undisturbed and unbroken vegetate,d corridor (either riparian or upland) that is at least 150 ft wide, has at least30% cover . of shrubs, forest or native undisturbed prairie, that connects to estuaries, other wetlands or undisturbed uplands that are at least250 acres in size? (damsinripariall corridors, heavily used gravel roads, paved roads, are considered breaks in the con·idor). ~. YES = 4 points (go to H 2.3) NO = go to H 2.2.2 H 2.2.2 Is the wetland part of a relatively undistur a.lInd unbro~n vegetated corridor (either riparian or upland) that is at least 50ft wide, has .at least3.0% cover of shrubs or forest, and connects to estuaries, other wetlands or undisturbed upllinds that are at least 25 acres in size? OR a Lake-Cringe wetland, if it does not have an undisturbed corridor as in the question above? YES.= 2 points (go to H 2.3) H 2.2.3 Is the wetland: @=H2.2.3 within 5 mi (8km) of a brackish or saIt water estuary OR within 3 mi of a large field or pasture (>40 acres) OR within 1 mi of a lake greater than 20 acres? YES=1 point Wetland Rating Form -westem Washington 15 (NO)= 0 points August 2004 I . o .. H 2.3 Near or adjacent to other priority habitats listed by WDFW (seep. 82) Which of the following priority habitats are within 330ft (loOm) of the wetland? (see text for a more detailed description of these pri01fty habitats) / Ripariall: The area adjacellt to aquatic systems with flowing water that contains elements of both aquatic and terrestrial ecosystems which mutuaJly influence each other. __ Aspen Stands: Pure or mixed stands of aspen greater than O.S ha (2 acres). __ Cliffs: Greater than 7.6 m (25 ft) high and occurring below 5000 ft. __ Old-growth forests: (Old-growtll west of Cascade crest) Stands of at least 2 tree species, fonninga multi-layered canopy with occasional small openings; with at least 20 treeslha (S trees/acre) > 81 em (32 in) dbh or > 200 years of age. __ Mature forests: Stands with average diameters exceeding 53 em (21 in) dbh; crown cover may be less that 100%; crown cover may be less that 100%; decay, decadence, numbers of snags, and quantity of large downed material is generally Jess than that found in. old-growth; 80 -200 years old west of the Cascade crest. __ Prairies: Relatively undisturbed areas (as indicated by dominance of native plants) where grasses and/or forbs form the natural climax plant community. __ Talus: Homogenous areas of rock rubble rangingin average size 0.15 -2.0 tIl (0.5 - 6.5 ft); composed of basalt, andesite, and/or sedimentary rock, including riprap slides and mine tailings. May be associated with cliffs. __ Caves: A naturally occurring cavity, recess, void, or system of interconnected passages _Oregon whit~ Oak: Woodlands Stands of pure oak or oaklconiferassociatioDS where canopy coverage of the oak component of the stand is 25%. __ Urban Natul'al Open Space: A priority species resides within or is adjacent to the open space and uses it for breeding and/or regular feeding; and/or the open space functions as a corridor connecting other priority habitats,especially those that would otherwise be isolated; and/or the open space is an isolated remnant of natural habitat larger than 4 ha (I 0 acres) and is surrounded by urban development. --..Estuary/Estuary-like: Deepwater tidal habitats and adjacent tidalwetlan!is,Usually- serni-enclosed by lahd but with open, partly obstructed or sporadic access to the open ocean, and in which oCean water is at least occasionally diluted by freshwater runoff from the land. The salinity may be periodically increased above that of the open ocean by evaporation. Along some low-energy coastlines there is appreciable dilution of sea water. EStuarine habitat extends upstream and landward to where oceaiJrderived salts measure less than O.5ppt. during the period of average annual low flow. InCludes both estuaries and lagoons. - __ Marine/Estuarine Shorelines: Shorelines include the intertidal and subtidal zones of beaches, and may also include the baclcshore andlldjacent components oftbe terrestrial landscape (e.g., cliffs, snags, mature trees, dunes, meadows) that are important to shoreline associated fish and wildlife and that contribute to shoreline function (e.g., sand/rockIJog recruitment, nutrient contribution, erosion control). Ifwetland has 3 or more priority habitats"" 4 points If wetland has 2 priority habitats ~ 3 paints Ifwetlandhas 1 prio® habitat = llloint No habitats = 0 points We!land Rating Form -western Washington 16 August 2004 H 2.4 Wetland Landscape (choose the Olle description of the landscape around the wetland that bestfits) (seep. 84) There are at least 3 other wetlands within Y, mile, and the connections between them are relatively undisturbed (light grazing between wetlands OK, as is lake shore with some boating, but connections should NOT be bisected by paved roads, fill, fields, or other development. points = 5 The wetland is Lake-fringe on a hike with little disturbance and there are 3 other Jak:e- fringe wetlands within Yo mile points == 5 1.-There are at least 3 other wetlands within Y, mile, BUT the connections between them are disturbed points:: 3 The wetland is Lake-fringe on a lake with disturbance and there are 3 other lake- fringe wetland within Yo mile points = 3 There is at least 1 wetland within Y, mile. points = 2 There are no wetlands within Y, mile. points = 0 H 2. TOTAL Score -opportunity for providing habitat b Add the scores in the column above Total Score for Habitat Functions -add the points for H 1, H 2 and record the result on n p.1 Wetland Rating Form -western Washington 17 Augnst 2004 CATEGORIZATION BASED ON SPECIAL CHARACTERISTICS Please determine ijtlle wetlalld meets the attributes described below and circle the appropriate answers and Catego/'y. Does the wetland meet the following criteria for Estuarine wetlands? -The dominant water regime is tidal, -Vegetated, and -With a salinity greater than 0.5 ppt. YES = Go to SC 1.1 NO ,/ SC 1.1 Is the wetland within a National Wildlife Refuge, National Park, National Estuary Reserve, Natural Area Preserve, State Park or Educational, Environmental, or Scientific Reserve under WAC 332-30-151? YES = SC 1.2 Is the wetland at least 1 acre in size and meets at least two of the following three conditions? YES = Category I NO = Category n -The wetland is relatively undisturbed (has no diking, ditching, filling, cultivation, grazing, and has less than 10% cover of non-native plant species. If the non-native Spartina spp. are the only species that cover more than 10% of the wetland, then the wetland should be given a dual rating (IITI). The area of Spartina would be rated a Category n while the relatively undisturbed upper marsh with native species would be a Category I. Do not, however, exclude the area of Spartina in determining the size threshold of 1 acre .. -At least % of the landward edge of the wetland has a 100 ft buffer of shrub, forest, or un-grazed or un-mowed grassland. -T4e wetland has at least 2 of the following features: tidal channels, depressions with open water, or contiguous freshwater wetlands. '. ,;";-'.' .. Wetland Rating Fonn -westem Washington· 18 August 2004 Cat. I Cat. I Cat.n Dual rating . lID -."- ", --~--~ -~--~.~-, -------- · , , ' GEOTECHNICAL ENGINEERING SERVICES 565 PRESSURE ZONE RESERVOIR RENTON, WASHINGTON OCTOBER 15, 2004 FOR CITY OF RENTON · J · , J · '\ , Geotechnical Engineering Services 565 Pressure Zone ReserVoir File No. 069-059-00 Prepared for: RWBeck 1001 Fourth Avenue, Suite 25010 Seattle, Washington 98154- Attention: R. Alan Bushley Prepared by: GeoEngineers, Inc. 8410 154th Avenue NE Redmond, Washington 98052 GeoEngineers, Inc. Thomas A. Tobin, PE October 15, 2004 · . 1, Principal Cop)'Iight«l 2004 by GeoEngineers.lnc. AU rights reserved. Disclaimer: Any electronic form, facsimile or hard copy of the Original document (email, text, table, and/or figure), if provided, and any attachments are only I copy of the original document The original document is stored by GeoEnginccrs. Inc. and win serve as the. official document of record. rue No. 0693-059-00 I TABLE OF CONTENTS Page No. INTRODUCTION ..................................................................•...•.................•.................................................. 1 PROJECT DESCRIPTION ...................•....................................................•.......•........•.................................. 1 FIELD EXPLORATIONS AND LABORATORY TESTING .............•.•............................................................ 1 FIELD EXPLORATIONS ......................................................................................................... : ........... 1 LABORATORY TESTING ................................................................................................................... 2 SITE CONDITIONS ..•.....•.............................................................................................................................. 2 GEOLOGy ..........••.........•.............................................................................................................•....... 2 SENSITIVE AREAS ............................................................................................................................. 2 SURFACE CONDITIONS .....................................................•.............................................................. 2 SUBSURFACE CONDITIONS ............................................................................................................ 2 Groundwater CondHions .............................................................................................. : .............. 3 CONCLUSIONS AND RECOMMENDATIONS ............................................................................................. 3 GENERAL. ..........•................................................................................................................................ 3 EARTHQUAKE ENGINEERING ..............................................•........................................................... 3 2003 IBC Seismic Design Information ....................................................................................... 3 SHe Response ............................................................................................................................ 4 EARTHWORK ......................................................•.........•..••....•...................................•......•............... .4 Clearing And Grubbing .............................•...............•.......•........................................................ 4 Subgrade Preparation .............................................•..........•......•............•.................................. .4 Erosion And Sedimentation Control ...............•...................•....................................................... 4 Structural Fill .............................................................•................•............................................... 5 Temporary Slopes .........................................•...........•.......................••.......•............................... 6 SHALLOW FOUNDATIONS .....•................................. : ....•.•.........•...•................................................... 6 General ..........................................................................................................................••........•• 6 Subgrade Preparation ...............................•...•...•...............................................•.•...................... 6 Shallow Foundation Design Criteria ..................................•.•.•...•......•........................................ 7 Mat Foundation .........................................................•.......................................•........................ 7 Lateral Resistance ........................................................•.......................•.... '" ............................. 7 Construction Considerations ..........................................................................................•.........•. 8 DEEP FOUNDATIONS ALTERNATIVES ....................................................................................•...... 8 General ..................................................... , ..........................•.•................................................... 8 PERMANENT GROUND ANCHORS .........................•...................••................................................... 9 DRAINAGE CONSIDERATIONS .......................................•.....................................................•.......... 9 Temporary Construction ...................................••.........•.....•..•••....•.........••.................................. 9 Permanent CondHions ............................................................................................................. 1 0 LIMITATIONS .................•.....................•....................................................•................................................. 10 REFERENCES ..........................................................................................•.....••.....•.................................... 11 List of Tables . Table 1. USGS Peak Ground Accelerations (bedrock) .....................................................................•.......... 2 Table 2. Earthquake Acceleration Time Histories ........................................................................................ 2 Table 3. Dynamic Soil Properties ......•.....•......................................................•..............................•.............. 3 File No. 069·059-00 October 15. 2()()./ Page; GEOENGINEERSg ".', ., .. List of Figures Figure 1. Vicinity Map Figure 2. Site Plan APPENDICES TABLE OF CONTENTS (CONTINUED) Page No. APPENDIX A -FIELD EXPLORATIONS .................................................................................................. A-1 Appendix A Figures Figure A-1 -Key to Exploration Logs Figures A-2...A-5 -Log of Borings APPENDIX B -LABORATORY TESTING ................................................................................................ B-1 Appendix B Figures Figure B-1 -Atterberg Limits Test Results· APPENDIX C -SITE SPECIFIC SEISMIC RESPONSE SPECTRA ..........•............................................. C-1 Appendix C Figures Figures C-1 ... C-2 -5% Damped Acceleration Response Spectra APPENDIX D -REPORT LIMITATIONS AND GUIDELINES FOR USE .....................•.................. D-1 ... D-3 File No. 069;-I!59-1JO OClOber 15. 2004 Pageii GEOENGIHEERSg I GEOTECHNICAL ENGINEERING SERVICES 565 PRESSURE ZONE RESERVOIR RENTON, WASHINGTON FOR CITY OF RENTON INTRODUCTION This report presents the results of our geotechnical engineering services for the proposed 565 Pressure Zone Reservoir project located in Renton, Washington. The project site is located on SE 112th Street in Renton, Washington. The site is shown relative to surrounding physical features on the Vicinity Map, Figure I and the Site Plan, Figure 2. The purpose of this study is to characterize the subsurface soil and groundwater conditions at the site and to provide RW Beck and the reservoir designer with geotechnical engineering design recommendations. GeoEngineers' geotechnical engineering services for this project consisted of reviewing existing geologic data and completing subsurface explorations at the site as a basis for developing geotechnical engineering conclusions and recommendations for the design and construction of the planned facility. Our geotechnical engineering services were completed in general accordance with the contract dated April 30, 2004 between RW Beck and GeoEngineers. PROJECT DESCRIPTION We understand that the City of Renton plans to construct a one-million-gallon water reservoir at the site. The reservoir will be located at the south end of the property near SE 112th Street. The project team initially considered both a standpipe and an elevated tank. We understand that the City has selected a standpipe for the reservoir configuration. The maximum water eleVation in the reservoir will be approximately 118 feet above the ground surface. We understand that the reserVoir foundation will be subjected to significant overturning loads under design seismic loading conditions. Based on discussions with the structural engineers, we understand that the reservoir foundation may incorporate deep foundation element to help resist the overturning loads as ground anchors. FIELD EXPLORATIONS AND LABORATORY TESTING FIELD EXPLORATIONS The subsurface soil and groundwater conditions at the site were evaluated by drilling four borings. Three borings, designated as borings B-1, B-3 and B-4, were drilled around the perimeter of the proposed water reservoir to depths of about 41 Y, feet. A fourth boring, designated as boring B-2, was drilled to a depth of about 70 feet near the middle of the proposed reservoir. The borings were completed on April 30 and May 3, 2004 using track-mounted, continuous-flight, hollow-stem auger drilling equipment. The approximate locations of the explorations completed for this project are presented on the Site Plan, Figure 2. Details of the field exploration program and logs of the explorations are presented in Appendix A. Fil. No. 0693-059-00 October /5. 2004 Pagel GEOENGINEERS g j. lABORATORY TESTING Soil samples were collecteq during the drilling program and taken to our laboratory for fwther evaluation. Selected samples were tested for the detennination of moisture content, fmes content (material passing the U.S. No. 200 sieve) and Atterberg limits (plasticity characteristics). A description of the laboratory testing and the test results are presented in Appendix B. SITE CONDITIONS GEOLOGY Published geologic information for the project vicinity includes the U.S. Geological Survey Map titled "Geologic Map of Surficial Deposits in the Seattle 30' x 60' Quadrangle, Washington" (yount, et. ai, 1993). The geologic map indicates that the surficial deposits in the vicinity of the site include glacial till and advance outwash. Glacial till typically consists of medium dense to very dense, non-stratified deposits of clay, silt, sand and gravel with occasional cobbles and boulders. Advance outwash consists of deposits of sand and gravel with variable silt content deposited by meltwater streams emanating from an advancing glacier. Advance outwash at the site has also been glacially overridden and is typically dense to very dense. SENSITIVE AREAS A review of the King County and City of Renton Sensitive Areas Maps was completed as part of this study. The project site is mapped within the City of Renton Zone 2 Aquifer Protection Area. Based on .the information published on the maps, the site is not mapped within a floodplain, seismic, wetland, critical erosion, or landslide hazard area. SURFACE CONDITIONS The project site is located on an undeveloped lot located along SE 112tb ,street in Renton, Washington. The site is bounded by SE 1121h Street and Oliver Hazen ,High School to the south, residences to the east, NE Sunset Boulevard to the north, and a soccer field for the high school to the west. We understand that the reservoir will be constructed near the south end of the property. The undeveloped site is forested with' deciduous trees and relatively heavy undergrowth typically consisting of ferns, blackberries and other shrubs. Several paths have been created through the forested area and appear to be used to access the soccer field as well as other parts of the property. The topography at the south end of the lot is relatively level. We did not observe surface water features in the vicinity of the proposed water reservoir during our site reconnaissance. SUBSURFACE CONDITIONS Approximately I to 1 V. feet of forest duff and topsoil containing significant amounts of organic material were observed at,the surface in each of the borings completed at the site. The surficial forest duff and topsoil was typically underlain by approximately 15 to 20 feet of medium stiff to hard silt and clay containing occasional thin sand lenses 1n borings B-1, B-2 and B-4. In boring B-3, we observed layers of silt and clay with interbedded layers of silty sand that extended down to about 33 feet below the surface. The silt and clay was typically underlain by dense to very dense sand with variable silt content and occasional layers of silt and gravel. Borings B-1, B-2 and B-3 were terminated in very dense silty sand at depths of 41 V., 70 and 41 Y, feet, respectively. Boring B-4 was terminated ina layer of very stiff silt at a depth of about 41 V. feet below the surface. File No. 0693..()59'(}(} Oclober 15. 2004 Page 2 GEOENGINEER5~ I'" I Groundwater Conditions Perched groundwater was observed in borings B-1 and B-2 at depths of20 and 18 feet respectively. Two layers of perched groundwater were observed in borings B-3 and B-4 at about 10 and 20 feet below the surface. The depths to groundwater represent conditions observed during drilling and may not represent the true static groundwater level because it can take hours or even days for the grOlmdwater level observed in a boring to reach equilibrium. Each of the borings was only open for a couple hours. It should be noted that the groundwater level will typically fluctuate as a function of season, precipitation and other factors. CONCLUSIONS AND RECOMMENDATIONS GENERAL We conclude that geotechnical site conditions are generally favorable for development of the site as proposed. Based on the results of our subsurface exploration and analyses, it is our opinion that the following considerations are . .appropriate for this site: o The proposed reservoir may be satisfactorily supported on either conventional shallow foundations or a mat foundation bearing on firm, unyielding native soil or compacted structural fill, or on deep foundations. Conventional spread footings should be considered for any ancillary buildings associated with the reservoir. • Several deep foundation options exist for this structure including driven steel pipe piles or H piles, augercast piles, drilled shafts, and drilled micropiles. Design recommendations can be developed for any of these foundation alternatives, lis necessary. o The on-site near surface soils do not meet the criteria for use as structural fill due to plasticity characteristics, fines content, high natural moisture content, and significant organic content. o The site soils meet the criteria 'for Soil Profile Type C in accordance with the 2003 IBC seismic design criteria. GeoEngineers has completed a site specific seismic response analysis for ground motions with a 10 percent and 2 percent probability of exceedance in 50 years. The results of the site specific seismic response analysis are presented in Appendix C. Our specific geotechnical recommendations are presented in the following sections of this report. EARTHQUAKE ENGINEERING 20031BC Seismic Design Information We recommend the use of the following 2003 International Building Code (IBC) parameters for soil profile type, short period spectral response acceleration (Ss), I-second period spectral response acceleration (S,), and seismic coefficients for the project site. . .' ? ' '2003 IBCParameter c::,:".,:,:, " . Soil Profile Type Short Period Spectral Response Acceleration, Ss (percent g) 1-Second Period Spectral Response Acceleration,S, (percent g) Seismic CoeffiCient, FA Seismic Coefficient Fv File No. 0693-1Jj9-00 October l.l. 2004 RecommendedValu;;2 C 134 47 1.0 1.33 GEoENGINEERS.JV Site Response Site-specific response analyses were completed to evaluate the response of the site for the following two design level earthquakes: 1. A ground motion with a 10 percent probability of exceedance in 50 years (475 year return interval). 2. A ground motion with a 2 percent probability of exceedance in 50 years (2,475 year return interval). Acceleration response spectra have been developed for both design level earthquakes for 5 percent structural damping. The methodology used for the site specific ground response analyses and the acceleration response spectra are presented in Appendix C. EARTHWORK Clearing And Grubbing The site is undeveloped and forested with relatively dense vegetation undergrowth. Organic-rich soils (forest duff and topsoil), trees, shrubs, vegetation, and associated root systems should be removed from areas where structures or pavements are planned. Based on our observations during the explorations, we anticipate that the stripping depths to remove the forest duff and topsoil will be on the order of 1 to 2 feet. Jncreased stripping depths may be required in localized areas around trees and large brush where the topsoil may extend deeper than 2 feet. Depressions that result from removal of existing trees that are present in pavement or structure areas should be filled with properly compacted structura1 fill. The stripped material should be placed in non-settlement sensitive areas or disposed of off-site. Subgrade Preparation The exposed subgrade in structure areas should be evaluated after site clearing and grubbing is complete and prior to the placement of any fill. Proof-rolling with heavy, rubber-tired construction equipment should be used for this purpose during dry weather and if access for this equipment is practical. Probing should be used to evaluate the subgrade during periods of wet weather or if access is not feasible for construction equipment. Soft areas noted during proof-rolling or probing should be excavated and replaced with compacted structural fIll. Erosion And Sedimentation Control Potential sources or causes of erosion and sedimentation depend upon construction methods, slope length and gradient, amount of soil exposed and/or disturbed, soil type, construction sequencing and weather. hnplementing an erosion and sedimentation control plan will reduce the project impact on erosion-prone areas and nearby sensitive areas. The plan should be designed in accordance with applicable city and county standards. The plan should incorporate basic planning principles including: • Scheduling grading and construction to reduce soil exposure. • Retaining existing vegetation whenever feasible. • Revegetating or mulching denuded areas. • Directing runoff away from denuded areas. • Reducing the length and steepness of slopes with exposed soils. • Decreasing runoff velocities. File No. 0693-O59"()() Ocwber J 5. 1004 Page 4 GEOENGINEERS g • Preparing drainage ways and outlets to handle concentrated or increased runoff. • Confining sediment to the project site. • Inspecting and maintaining control measures frequently. In addition, we recommend that slope surfaces in exposed or disturbed soil be restored so that surface runoff does not become channeled. Some sloughing and raveling of slopes with exposed or disturbed soil should be expected. Temporary erosion protection should be used and maintained in areas with exposed or disturbed soils to help reduce erosion and reduce transport of sediment to adjacent areas and receiving waters. Permanent erosion protection should be provided by re-establishing vegetation using hydro seeding or landscape planting. Until the permanent erosion protection is established and the site is stabilized, site observation should be performed by qualified personnel to evaluate the effectiveness of the erosion control measures and provide recommendations to repair andlor modify them as appropriate. Provisions for modifications to the erosion control system based on monitoring observations should be included in the erosion and sedimentation control plan. Structural Fill Fill placed to support structures and placed below pavements and sidewalks will need to be specified as structural·fill as described below: 1. Structural fill placed below the reservoir foundation or beneath ancillary building footings and slabs should meet the requirements of gravel borrow as descnbed in Section 9-03.14(1) of the 2004 WSDOT Standard Specifications with the exception that the fines content (percent passing the U.S. No. 200 sieve) should be less than 5 percent. 2. Structural fill placed outside of building areas (such as utility trenches, below pavement and sidewalk areas) should meet the requirements of COrnmon borrow as descnbed in Section 9- 03.14(3) ofthe 2004 WSDOT Standard Specifications. Cornmon borrow will be suitable for use as structural fill during dry weather conditions only. If structural fill is placed during wet weather, the structura1 fill should consist of gravel borrow as described previously. On-site Solis. The on-site soils generally contain a high percentage of fmes (silt and clay) and are sensitive to moisture content. Existing near-surface silty soils do not meet the criteria for common borrow and are unsuitable for use as structural fill. Fill Placement and Compaction Criteria. Structural fill should be mechanically compacted to a firm, non-yielding condition. Structurill fill should be placed in loose lifts not exceeding 8 to 10 inches in thicmess. Each lift should be conditioned to the proper moisture content and compacted to the specified density before placing subsequent lifts. Structural fill placed in building areas (supporting foundations or slab on grade floors) and in pavement and sidewalk areas (including utility trench backfill) should be compacted to at least 95 percent of the maximum dry density (MDD) estimated in accordance with ASTM D-1557. We recommend that GeoEngineers be present during proof-rolling andlor probing of the exposed subgrade soils in building and pavement areas, and placement of structural fill. We will evaluate the adequacy of the subgrade soils and identify areas needing further work, perform in-place moisture-<iensity File No. 0693-1159-00 October 15. 2004 PageS GEOENGINE£RSg tests in the fill to confirm compliance with the compaction specifications, and advise on any modifications to the procedures which may be appropriate for the prevailing conditions. Weather Considerations. The majority of the near surface soils at the site contain a sufficient percentage of fines (silt and clay) to be moisture sensitive. When the moisture content of these soils is more than a few percent above the optimum moisture content, these soils become muddy and unstable and operation of equipment on these soils would be difficult, if not impossible. Additionally, disturbance of near surface soils should be expected if earthwork is completed during periods of wet weather. During wet weather, we recommend that: • The ground surface in and around the work area be sloped so that surface water is directed away from the work area. The ground surface should be graded such that areas of ponded water do not develop. Measures should be taken by the contractor to prevent surface water from collecting in excavations and trenches. Measures should be implemented to remove surface water from the work area. • Slopes with exposed soils should be covered with plastic sheeting or other erosion protection material. • Construction traffic should be restricted to specific areas of the site, preferably areas that are surfaced with materials not susceptible to wet weather disturbance. • Construction activities should be scheduled so that the length of time that soils are left exposed to moisture is reduced to the extent practical. Temporary.Slopes Temporary slopes may be used around the site during construction. We recommend temporary slopes be inclined at IH: 1 V (horizontal to vertical). Flatter slopes may be necessary if seepage is present on the face of the cut slopes or iflocalized sloughing occurs. Since the contractor bas control of the construction operations, the contractor should be made responsible for the stability of cut slopes, as well as the safety of the excavations. Shoring and temporary slopes must conform to applicable local, state and federal safety regulations. SHALLOW FOUNDATIONS General The water reservoir can be supported on either shallow foundations or deep foundations. We understand that if shallow foundations are chosen, the foundation system will consist of either isolated footings, strip footings or a mat foundation. We recommend supporting any ancillary buildings associated with the water reservoir on conventional spread footings. Subgrade Preparation If shallow foundations are chosen for the reservoir or buildings, we recommend supporting these structures on footings bearing on undisturbed, firm and unyielding native soil or compacted structuraJ fill extending down to unyielding native soil. We recommend that all prepared footing subgrades be observed by a representative from our finn prior to placement of reinforcing steel and structural concrete to conflIlD. that the subsurface conditions are as expected and that the hearing surface bas been prepared in a manner consistent with our recommendations. Footing excavations should be evaluated by probing prior to concrete or fill placement, and soft or loose areas should be over-excavated and replaced in accordance with the recommendations of this report. Fi~ No. 0693'()J9-f)O OcIOber H. 1004 Page 6 GEOENGINEE~ Shallow Foundation Design Criteria Assuming the footings are fOWlded on Wldisturbed, firm and Wlyielding native soil or adequately compacted structural fill extending down to unyielding native soil, the footings can be designed in accordance with the following reconnnendations: • The footings may be designed for an allowable bearing capacity of 7 kips per square foot (lest). The allowable soil bearing values apply to the total of dead and long-term live loads and may be increased by up to one-third for wind or seismic loads. • Exterior footings should be fOWlded a minimum of 18 inches below the lowest adjacent grade. Interior footings should be fOWlded a minimum of 12 inches below adjacent soil grade. • Continuous wall footings and individual column footings should have minimum widths of 18 and 24 inches, respectively. • Provided all loose soil is removed and the sub grade is prepared as recommended above, post- construction settlement of shallow fouridations supported as recommended above is estimated to be about I inch. • Post-construction differential settlement along 25 feet of continuous strip· footing or between similarly loaded isolated footings about 25 feet apart is estimated to be about Yl inch. These settlements should occur rapidly, essentially as the loads are applied. Mat Foundation Assuming the mat fOWldation is fOWlded on undisturbed, firm and unyielding native soil or adequately compacted structural fill extending down to Wlyielding native soil, the fOWldation can be design in accordance with the following recommendations: • Mat fOWldations may be designed using a modulus of subgrade reaction of 50 pOWlds per cubic inch. Ibis value applies to the total of dead and long-term live loads and may be increased by up to one-third for wind or seismic loads. • Provided all loose soil is removed and the subgrade is prepared as recommended above, we estimate the total settlement of mat foundations will be on the order of I to I Yl inches. The settlements will occur rapidly, essentially as' loads are applied. Differential settlements are expected to be less than Yl to % inches over a 50-foot length. Lateral Resistance Lateral fOWldation loads may be resisted by passive resistance on the sides offootings and by friction on the base of the footings. For footings supported on native soils or on structura1 fill placed and compacted in accordance with our recommendations, the allowable frictional resistance may be computed using a coefficient of friction of 0.4 applied to vertical dead-load forces. Ibis coefficient of friction value is an allowable value and incorporates a factor of safety of 1.5. The allowable passive resistance may be computed using an equivalent Uuid density of 275 pounds per cubic foot (pct) (triangular distribution). Ibis value is appropriate for fOWldation elements that are poured directly against Wldisturbed native soils or surrounded by structural fill. The passive equivalent fluid density is an allowable value and incorporates a factor of safety of 1.5. File No. 0693-1159-{)O October J 5, 20()4 Page 7 GEOEN.GIHEERS~ ".-J • ., Construction Considerations The condition of all footing excavations should be observed by the geotechnical engineer to evaluate if the work is completed in accordance with our recommendations and that the subsurface conditions are as anticipated. If footing subgrade preparation takes place during the wet weather season, we recommend that the footing concrete be placed as soon as practical after the footing subgrade has been evaluated by a representative from our firm. We anticipate that the footing subgrade will consist of soils with a high fmes content (material passing the U.S. No. 200 sieve). Should the subgrade remain exposed for an extended time during the wet weather season, we recommend that a working mat of lean concrete or minimum 12-inch thickness of compacted crushed rock or 4-inch minus quarry spalls be placed on the footing subgrade. The lean mix concrete, crushed rock or quarry spalls will protect the subgrade from deterioration during placement offorms and structural steel. DEEP FOUNDATIONS ALTERNATIVES General There are several potential options if deep foundations are incorporated into the foundation system for the proposed water reservoir. Deep foundation options include: H-piles, steel pipe piles, augercast piles, drilled shafts, or micropiles. Each deep foundation option will have advantages and potential disadvantages that will need to be considered as a foundation system is chosen. H-piles or steel pipe piles will need to be driven into the ground. Because of the close proximity of the school and adjacent residences, the vibrations that are generated during pile driving conditions may not be acceptable. Should H-piles or steel pipe piles be chosen, pile corrosion will need to be addressed to determine how it might impact the design. The installation of augercast piles will generate minimal vibration as they are not driven into the ground. Based on our experience with similar projects, augercast piles will likely be the most economical deep foundation option. The soil conditions encountered at the site are suitable for drilled shaft construction. We did observe heaving conditions near the bottom of boring B-1. The heaving observed during drilling of boring B-1 may be indicative of unstable soil conditions for open shafts. Therefore, it is likely that the shafts may need to be cased or drilled with slurry or a water head. These conditions will likely result in an increase in the cost of the drilled shafts. Augercast and drilled shaft foundations are capable of accommodating design vertical loads over a wide range of values deperiding on shaft diameter and depth. Typical loads range from less than 100 kips for small diameter shafts (augercast) to several hundred kips for large diameter drilled shafts. Uplift capacities of drilled foundations typically range from about 50 to 75 percent of the downward load capacities of the shafts. Micropiles typically provide relatively high uplift capacities. Micropiles are small diameter (typically 6-to 8-inch), drilled and grouted pile that is typically reinforced. Grouting can be completed under tremie head or by pressure grouting. Post-grouting can also be used to increase capacities. High capacities of several hundred kips can be achieved using a relatively small diameter pile (typically 6-to 8- Fih No. 0693-O59.()() October J 5. 2004 Page 8 GEOENGINEE~ inch diameter) because the pile grout is placed under high pressure. However, they are typically a design- build fOUildation element and can be expensive. Boulders may be encountered in the glacially consolidated soils. The contractor should be prepared to address the presence of boulders during construction. We can provide design recommendation for the preferred deep foundation alternative, as necessary, once the final foundation system has been selected. PERMANENT GROUND ANCHORS If additional uplift capacity is required in the design of the reservoir, permanent ground anchors may be considered. Permanent ground anchors are similar to tiebacks and typically consist of a steel bar or tendon. In gener!ll, the installation process consists of drilling a hole to a specified depth, inserting the ground anchor and tremie grouting the anchor in place. Centralizers should be used to keep the anchor in the center of the hole during grouting. Structural grout or concrete should be used to fill the annulus around the anchor. We recommend that the ground anchors be double-corrosion protected because they will support load on a permanent basis. Secondary grouting can be utilized to improve the anchor capacity. Loose soil and slough should be removed from the holes drilled for ground anchors prior to installing the anchors. The contractor should take necessary precautions to minimize loss of ground and prevent disturbance to previously installed anchors. Heaving soils' were observed in boring B-1 and may be indicative of unstable soil conditions for open boreholes. It may be necessary to drill holes for anchors with casing or slurry to prevent caving. Holes drilled for anchors should be. grouted promptly to reduce the potential for loss of ground. Boulders may be encountered in the glacially consolidated soils. The contractor should be prepared to address the presence of boulders during construction. Ground anchors should develop anchorage in the very dense or very stiff to hard glacially consolidated soils. We recommend a preliminary design adhesion value between the anchor and soil of 1.5 to 2 ksf. Higher adhesion values may be developed depending on the anchor installation technique. The contractor should be given the opportunity to use higher adhesion values by conducting performance tests prior to the start of the production ground anchor installation. Ground anchors are typically performance and proof tested to confirm that the anchors have adequate pullout capacity. The pullout resistance of an anchor should be designed using a factor of safety of 2. The pullout resistance should be verified by completing at least one successful performance test. Each anchor should be proof tested to confirm that they can provide the design pullout capacity. The ground anchor layout and inclination should be checked by the contractor to confirm that the anchors do not interfere with foundation elements for adjacent structures or other existing improvements such as buried utilities. DRAINAGE CONSIDERATIONS Temporary Construction The soils exposed in the base of the excavations will be moisture-sensitive and susceptible to disturbance from construction activities, especially when water is present on the sub grade. A system of curbs, berms, drainage ditches and swales should be installed around the perimeter of the excavation, if necessary, to intercept and collect surface water. File No. 0693..IJ59-00 October 15. 2004 Page 9 GEOENGINEERS ~ Perched groWldwater may be encOlmtered on top of less permeable layers dining excavation for footings. We anticipate that this perched water may be temporarily bandied dining construction by ditching and sump pumping, as nece.ssary. Water collected dining construction should be routed to suitable discharge points. PertnanenfCondHions We recommend that all surfaces be sloped to drain away from the proposed building or reservoir areas. Pavement surfaces and open space areas should be sloped such that the sUrface water is collected and routed to suitable discharge points. Roof drains should be connected to tightlines that discharge into the storm sewer disposal system or engineered surface water control system. LIMITATIONS We have prepared this report for the exclusive ·use of the City of Renton, R W Beck and their authorized agents for the 565 Pressure Zone Reservoir project. . Within the limitationsohcope, schedule and budget, our services have been executed in accordance with generally accepted practices in the field of geotechnical engineering in this area at the time this report was prepared. No warranty or other conditions, express or implied, should be understood. , Any electronic form, facsimile or hard copy of the original docuri1ent (email, text, table, andlor figure), if provided, and any attachments are only a copy of the original document. The original document is stored 'by GeoEngineers, Inc. and will serve as the official document ofrecord. Please refer to Appendix D titled Report Limitations and Guidelines for Use for additional information pertaining to use of this report. File No. 0693-059-00 October 15, 2004 Page 10 GEOENGINEER~ REFERENCES City of Renton, Sensitive Areas Maps, 1992. EduPro Civil Systems, Inc. (1998). ProShake, Ground Response Analysis Program, Version 1.1 Frankel, A., Mueller, C., Barnhard, T., Perkins, D., Leyendecker, E., Dickman, N., Hanson, S., and Hopper, M. (1996). National Seismic-Hazard Maps: Documentation. U.S. Geological Survey Open-File Report 96-532, 110 pp. Frankel, A.D.; Petersen, M.D.; Mueller, C.S.; Haller, K.M.; Wheeler, R.L.; Leyendecker, E.Y.; Wesson, R.L.; Harmsen, S.C.; Cramer, C.H.; Perkins, D.M.; and, Rukstales, K.S. (2002). Documentation for the 2002 Update of the National Seismic Hazard Maps. U.S. Geological Survey· Open-File Report 02-420. mc (2003). International Building Code 2003. King County, Sensitive Areas Maps. U.S. Geological Survey -National Seismic Hazard Mapping Project -Interactive Deaggregations. URL: http://eqint.cr.usgs.gov/eqlhtmVdeaggint.html WSDOT, 2004, "Standard Specifications for Road, Bridge and Municipal Construction." Yount, et. al, 1985, "Map Showing Depth to Bedrock in the Seattle 30' 1\ 60' Quadrangle, Washington." Yount, et. aI, 1993, "Geologic Map of Surficial Deposits in the Seattle 30' x 60' Quadrangle, Washington. " Fik No. 0693-1JS9-(}() Daober 15. 2004 Page 11 GEoENGINEER~ 'J o I 2000 ! SCALE IN FEET .. REN 4000 w;th perm;ss;on granted by THOMAS BROS. MAPS. Th;s map ;s copyr;gl\ted by THOMAS BROS. MAPS. to or 011 or thereof whether for or resole. without VICINITY MAP GEoENGINEERS IiJ FIGURE 1 1) ~ w w ~ Z --..£:-z 0 • 0 ~ 0= ~ ~ z 4 ~ ~ Q. X w 0 I [, ;-[, " z i? 0 ro + , ro l>O/OI/90 t', ;; • <; Z ;; o c ~ '" • '" N W a: ::> '" ii: ~ a:: ... ... Z 1!1 Z W @ l!) !)M()·VOO6;or690\(]'v'::J\OO\6c,;;or690\d\ri03~ . , . , GEoENGINEERS!IJ ApPENDIX A FIELD EXPLORA TIONS SOil CLASSIFICA nON CHART MAJOR 1lMSI0NS SYMBOLS 'TYPICAL DESCRIPTIONS -GRAlHED sou ".. ....... 0 SOLS ----"" ... ..... ..... 0 ANO .... OY SOlLS -"""-......... -....... "" . .... SILTS AND etAYS • • •• •• GP ~~·~h· PJH.IH .. L~---r----------~ OH ~cu.ftANO!II.l1IOP .1. IoIIOIJM 1'0 I4IiH I'UoItICIT't HIGHI. Y ORGANIC SOfl.S Sampler Symbol Descriptions II 2.4-inch I.D. spilt barrel [I Standard Penetration rest (SPT) o Shelby tube ~ Piston IJ DIrect·Push tgI Bulk or grab Blowcount is recorded for driven samplers as the number afblows required to advance sampler 12 Inches (or dfstance noted). Sa. exploration log for hammer weight and drop. A "PO Indl_ sampler pushed using the weight of the drRl rig. ADDmONAL MATERIAL SYMBOl.S %F At CA CP CS OS HA MC 1\10 OC PM PP SA TX UC VS NS SS MS HS NT CC Cement Concrete . AC Asphal Canaetts CR Crushed Rockl Quany Spalla TS TopsolU Forest DuffiSod Moasunod g"nmd .. "tar level In exploration, well, or piezometer Groundwater obMrved at tfme of exploration Perched water observed at time of exploration Measured free product in W'tIn or piezometer' . Stratigraphic Contact DIstinct contact between soU strata or geologic units Gradual change between 5011_ or geologic units Approximate location of soIl_ change within a geoJoglc soil unit Laboratory I Field Tests Percent fines Attetb<orgJlmits Chemical analysis Laboratory compactfon test Consolidation test Oirocishear Hydrometer analysis Moisture content Motstu,.. content and dry density Organic content Perm .. billty or hy<lraulio conductivity Pocket penetrometer Sieve analysis TrlaxiaJ compression Unconfined compression Vane shear Sheen Classlflcation No VIsIble S_n Saght Shean Mcderala Sheen HeavySheon Not Teslad NOTE; The ruder mUSl mfer to the discussion in the report !ext and ttl_logs of txploradons for a proper understanding of subsurface conditions. 0escriptic11l on ttl_logs apply only at !he ",ecfflc axptoraticln locations and at the time the explOrations were made; they ate notwaranied to be representative of sUbsurface condIUons at ather IDeations or tines. KEY TO EXPLORATION LOGS GEoENGINEERS CJ Figure A"1 08te(5) 04/30/04 Logged KGO Checked MWS Drilled By By Orifting Holt Drilling DfIInng Hollow-stem Auger Sampling SPT Contractor Method M.thOds Auger 4.25-inch 10 Hammer 140 (Ib) hammer/3D (in) drop orilnng Umited Access Rig Date Data automatic Equipment Total 41.5 Surface Approximately 456 Groundwater 20 Dapth (It) EieVlItion (ft) LIIV8I(ft.bgs) oa .. mI System SAMPIFS = I~ I, 0: 01 OTHER TESTS MATERIAL DESCRIPTION 1f. B .c ;~ li §~ AND NOTES ;; !j .' .!! :~ 5~ Forest UU," 'U",u,j with organic matter . ML B",.w,,-~ilt with thill_' I lay .... of fine S8lId . (stiff to very stiff, moist) 1 I 14 10 20 AL 5- 12 S -- 23 'Y.f-98% ~ 3, 18 ML ~~::7Ei~;r~!~ Sll~:~= ~ fine sand -21 10- ] 4 i 18 -- 38 ] 5 118 28 Grades to gray 15- ] 6 118 SM -Gray~ ! . ai~~ii : silty : - 23 WI occaslon ="'"', woiStto wet) - SM . u(:~~~ "0' ,,~ Silty fine sand 20- ] 7 IS V _ wet) - ~ 41 28 ~ <,."JUT _ Gra,i;~!~) . with silty fine sand l. ~ 25-] 18 43' - - , . . . , . , . , . 30- ] 9 -- IS 35 .. ' SP·SM Brown fine sana with silt l dense to very dense, wet) :: ' .. ~ See Figure A-I for ~ianat;an of ~ala -~ LOG OF BORING B-1 GEoENGINEERS (ij 'V,vv', 565 Pressure Zone "~Q~; .vn Project Location: Renton, Washington , ~'!.:t0l ~;2 Number. 0693-059-00 ,. " ," " ," SAMPLES MATERIAL DESCRIPTION c ~ 1 0 ... "8 ~ :5 -I!! ~ ~ " ; I -J ~ 0.:8 >-0.-~ .i J!~ "" "-"E w_ e.g! .!! " .. g3' e» 35 .s za: 3: (!J Ul, J 10 8 OISVa ", " , 40-1-1 1111 12 57 UL-L~-L-ll~ __ -L ______________________ _ ,'-::: : ,3M r-BlOwn ,Uty fine sand (very dens., wet) OTHER TESTS AND NOTES Silt in abo< , , :,,~;~===================='======================~ LOG OF BORING B·1 (continued) i GEoENGINEERS UJ Project: 565 Pressure Zone Reservoir Project Location: Renton, Washington Project Number: 0693-059-00 Figure: A-2 Sheet 2 of2 Oate(s) 04/30/04 Logged KGO Checked MWS Onled By By Drilling Holt Drilling OriDing Hollow·stem Auger Sampling SPT Conlractor Method MethQds Auger 4.25·inch 10 Hammer 140 (Ib) hammerl 30 Qn) drop Onliing . Limited Access Rig De .. 0 ... automatic Equipment Total 70.5 Surlace Approximately 456 Groundwater 18 Depth (ft) 9"""lIon (ft) Level (11. bgs) . 0aIumI System ,:: ...... "1 t:,:: " ig It ~ OTHER TESTS i l~ MATERIAL DESCRIPTION ..,. .II r1 § AND NOTES i;Qj It iIiS j, ~. 0 IU farest dull" and topsoil .: matter · . ML Gray witll or~ge : silt I . :to very · . ] I ,12 s·tiff. moist) S 22 " 5- . f-- ] 21 0 20 ; SM Gnt~e~rawn with : silty fine sand ' moist) ] l il8 20 14 %F-45% . 10-~ 'In ML f-Brown with orange : silt with sand.~!~Vel _ 37 and occasional lenses or-fine sand (hard. . pol I S0/2" ML _ Gray I (very stiff, maist) 15-~6 ... - 18 30 22 %F.-92% If. .•. SM G(~~~. fine to medium sand with, I gravel dense, wet) · 20- ] 7 18 · . -- I 61 Thin layer Qfgravel at21 f=t · . · . ~ ML Grath:\th orang,_ mOttlin~ ~ilt witll:'~n and , 25- layers of fine sand (hard, 'uv.st'n wet) -~ ]8 -Occasional horizonrallaminations 18 SO/SO · Ocoasional horizontal. laminations · · · 30-]9 -- 2 6t · · SM Brown silty fme to medium sand (dense, wet) ~ See Figure A·l far explanation af';"bals - N LOG OF BORING 8-2 " GEoENGINEERS CJ ro VJ""'. 565 Pressure Zone Project Location: Renton. Washington Figure: A·3 Number: 0693·059-00 Sheet 1 al2 SAMPLES is g "0 ~ OTHER TESTS " C i; MATERIAL DESCRIPTION ;f. &I ;0 I!! AND NOTES " .c ~ § 1 ....I .lI c.:8 ~i .:a..; :>-i'i "iii ! dlJ ! I -a ;j"" E "E 1= ~,S!' oJ! " .. I! 8' e". 35 .s zc:: iii (!)..J elm ~8 Q~ J 10 " ' 18 45 "-. . : .. , " " , . " SP-sM Gray1slibrownTme to medium IlUIdWitll'lit and " occasional thin layers of silt (v~ dense, wet) , " 40-]11 ~ - 18 n ' " I- " ", l- I- " I- 45-fJlI2 4 5014" k • GP I-CliiIy line to coarse gravel with ,and and trace ,ilt (very_ • d~et wet) • • • .; SM Gray silty fine to medium ,and Wlth gravel (very dense, Glw:ialtill fabric ,', moist) , , , , , ' , , . SO-t! 13 10 SOI4" ' , ~ -: , " : , , -: : : , " SM Gray 'ilty fine sand (very dense, wet) .;. ' ' 55-~14 ' , I--, , ' , 18 63 ' ' , , , ' " , ',' , ' , ' " , , 60-~lS . -: .. ~ Grades to mOist'to wet - II 68 , , " , , : Glacial till fabric '," SM Gray silty fIDe to medium sand with gravel (very dense, , ' moist) , ~ 65-~16 .. I--'.' -' 1i · 14 71 ' . 5 .. ' ... :;: , . " .' ;0 · '-: .. .:. ' ' ill · ," . ~ 70-b; 17 . -: : . t,--.. 4 SOlS" ' , "' ',' I Refusal for limited access rig -insufficient torque I !:l .. '" ~ ~ LOG OF BORING 8-2 (continued) ~ Project: 565 Pressure Zone Reservoir i GEoENGINEERS CJ Project Location: Renton, Washington Figure: A·3 i Project Number: 0693-059-00 Sheet 2 012 Dale(') 00_ D_g Contractor Auger Data Total Daplh 1ft) Daluml Syelam 05103/04 Holt Drilling 4.25-inch 10 41.5 ML SM ML SM ML SM CH ML SM TS:! Ched<od By Oriling Hollow-stem Auger Sampling Method Methods Hammer drop Drilling o.ta Equipment Surface Approximately 456 G"",_ Elevation (ft) Live! (ft. bgs) MATERIAL DESCRIPTION 19 24 Becomes wet See Figull: A-I for explanation of symbols GEoENGINEERS CJ LOG OF BORING 8-3 Zone Reservoir Project Location: Renton, Washington Number: 0693-059-00 MWS SPT Limited Access Rig 19.5 OTHER TESTS AND NOTES %P'"'3S% Occasional slickensides. diced fabric SAMPLES c g Ii ~ OTHER TESTS 0 i! 0 ,. MATERIAL DESCRIPTION ;l-.e :; .. AND NOTES .s:: 4; g ~ -' :l! "i ~:e 11 ic 1 ~ 8 ~ a.Q ~D ~ ~ a. ,,'" i c => .. co!! I!'" 01: d~ w_ " .. ~ ... 3:8 35 .s zo: iii (!loS (!lo> J 10 ,' .. 18 67 .: ' . . :. · . ' .. ' .. . '. · . · . · . " .. 40-111 · . · . -' - 18 54 · . · . ,,' . , . '. ~ li l- S '" ~ ;: I ~ I .. ~ '" .. ~ r; LOG OFBORING B-3 (continued) ~ Project: 565 Pressure Zone Reservoir I GEoENGINEERS CJ Project Location: Renton, Washington Figure: A-4 i Project Number. 0693-059-00 Sheet 2 of 2 Oate(.) OMlIe< Drilling Contractor AU9er Data Total Depth 1ft) Cstwn/ System - 05103104 Holt Drilling 4.25-inch 10 41.5 """'''' ,:" ~I I 9 5-~ 2 1 '8 58 ~ 118 43 10-] 4 18 24 ] 5 18 II 15-] 6 ,18 26 20-] ,,- 7 1'8 41 25- ] 8 18 73 ' '. 30- ] 9 18 S4 Legge< By Orilllng Method TB2 Hollow-stem Auger Checke< By SampHng Methods ~:mer 140 (Ib)~, I 30 (in jdrOP !?"lIng Surfaca Elevation {ft} Approximately 455 MATERIAL DESCRIPTION Groundwater Level (ft. bgs) ML _ . gray with , : silt with sand _ (hard, moist} 18 19 , gravel (very stiff, _ 8M nrowTiiSlli!igraiYySiltY Sllty'fiDe' tine,,~andll ([deiiSdensee.;" moinoiSi,st))--. -- ML -' t (hard, moISt) -- -r - SM " tme sand (dellse to very , "J -- , , ' --See Figure A-I for e>pianation of symbol, LOG OF BORING B-4 GEoENGINEERS CJ Project: 565 Pressure Zone Reservoir ~roject Location: Renton, Washington Number: 0693-059-00 MWS SPT Limited Access Rig 20 OTHER TESTS AND NOTES %F-60% Occasional slickensides, diced. filbric AL I SAAIPLES ;;; } c '" ;; OTHER TESTS 0 ) (j ,. MATERIAL DESCRIPTION .. = .<:: j .j .. . AND NOTES .. OJ .! ~ ail) Ci.-j ~l =.2 ,!J a E "-s= ::J", IDS s " ~ as ~8 g~ 3S S z Cl", ~ 10 ',' . ' IS 40 .: ... , , '" .. .... . ML Brown silt with sand and ocoasional gravel (very stitt, moist to wet) 40-~ll -- 18 29 ~ ;;; .. c ~ ~ ~ ~ 1; I ~ I ... ~ .. ~ ~ LOG OF BORING B-4(continued) iii '" Project: 565' Pressure Zone Reservoir 8 GEoENGINEERS (jJ I Project Location: Renton, Washington Figure: A-5 Project Number: 0693-059-00 Sheet2of2 GEoENGINEERS Ii) ApPENDlxB • LABORATORY TESTING GENERAL APPENDIXB LABORATORY TESTING - Soil samples obtained from the explorations were transported to our laboratory and evaluated to confirm or modify field classifications, as well as to evaluate engineering properties of the soil samples. Representative samples were selected for laboratory testing consisting of the detennination of moisture content, percent fines (material passing the U.S. No. 200 sieve) and the Atterberg limits. The tests were performed in general accordance with test methods of the American Society for Testing and Materials (AS1M) or other applicable procedures. The results of the moisture content and percent fines tests are presented on the exploration logs at the respective sample depths in Appendix A. The results of the Atterberg Limits testing are presented in Figure B-1. MOISTURE CONTENT-TESTING Moisture content tests were completed in general accordance with ASTM D 2216 for representative samples obtained froin the explorations. The results of these tests are presented on the exploration logs in Appendix A at the depths at which the samples were obtained. PERCENT PASSING U.S. No. 200 SIEVE (%F) Selected samples were ''washed'' through the No. 200 mesh sieve to estimate the relative percentages of coarse and fine-grained particles in the soil. The percent passing value represents the percentage by weight of the sample finer than the U.S. No. 200 sieve. 'These tests were conducted to verify field descriptions and to estimate the fines content for analysis purposes. The tests were conducted in accordance with ASTM D 1140, and the results are shown on the exploration logs at the respective sample depths. ATTERBERG LIMITS Atterberg limits testing was performed on selected fine-grained soil samples. The tests were used to classify the soil as well as to evaluate index properties. The liquid limit and the plastic limit were estimated through a procedure performed in general accordance with ASTM D 4318. The results of the Atterberg limits testing are summarized in Figure B-1. File No. 069.()j9-OO October 15. 1004 Page B-1 GEOENGINEiR~ 0693-059-00 MWS: MR4: Jvj ·5-10-04 (Atterbergs.ppl) 1l'G\ PLASTICITY CHART !t m ~O 60 !m / .. / ~z .,/ /' ~G'I ./ ..-& 50 S-z / ,/ V I:! m m ... / .... CH or OH/ ::u >< 40 ~ w / ./' ~ /' 0 I z ~ 30 ,/ OC" , () L ~~~/ / i= 0' , en ..-OH orMH ~ 20 / /" / V //~:.: V ry ..... ~ 10 / / ./ 111 / CL-ML ...". Ml orOl :u '/ m 0 m :u 0 10 20 30 40 50 60 70 80 90 100 J! .., .., C LIQUID LIMIT c ;: :u ::j 111 1/1 m -I • 111 EXPLORA TtON SAMPLE MOISTURE lIOUID PLASTICITY -~ SYMBOL NUMBER DEPTH CONTENT("") LIMIT (%) INDEX("") SOIL DESCRIPTION :u m 1/1 C !:j : B-1 3.0' 20 28 6 Brown sUI (ML) 1/1 B-4 13.0' 19 60 34 Oray clay (CH) . GEoENGINEERS I;; ApPEND/XC SITE SPECIFIC SEISMIC RESPONSE SPECTRA APPENDIXC SITE SPECIFIC SEISMIC RESPONSE SPECTRA SITE SPECIFIC GROUND RESPONSE ANALYSES General Site specific ground response analyses were completed to develop acceleration response spectra at the project site for the following risk levels: 1. A ground motion with a 10 percent probability ofexceedance in 50 years (475-year event). 2. A grolmd motion with a 2 percent probability of exceedance in 50 years (2,475-year event). A summary of the methodology used to develop the site specific seismic response spectra is presented in the following sections of this report. Earthquake Source Zones General. Seismicity in the Puget Sound area is primarily driven by the Cascadia Subduction Zone (CSZ), which is the zone where the westward advancing North American Plate is overriding the . subducting Juan de Fuca Plate. The interaction of these two plates results in three potential seistiric source zones for the Puget SOlmd area: (I) shallow crusta! earthquakes within the overriding North . American Plate associated with known and/or Wlknown faults; (2) CSZ interplate earthquakes, which occur along the boundary located between the Juan de Fuca and North American plates; and (3) CSZ intraplate earthquakes, which occur within the subducting Juan de Fuca Plate (deep subcrustal earthquakes). Shallow Crustal Earthquakes. The shallow crustal source zone is characterized as being capable of . generating earthquakes up to about magnitude 7.5 between depths of about 5 to 30 k:m. Shallow crustal faults with known or suspected Quaternary displacements within the project area include the Seattle Fault, located within approximately 3 kilometers of the site. The Seattle Fault is believed to have generated an approximate magnitude 7.0 earthquake 1100 years ago. CSZ Interplate Earthquakes. There is no instrumentally recorded seismicity of large interplate earthquakes for the CSZ. The CSZ interplate source zone generally extends along the coast from northern California to British Columbia and is characterized by researchers as being capable of generating earthquakes of magnitude 8 to magnitude 9. Recurrence intervals for CSZ interplate earthquakes are thought to be on the order of 500 years, which is substantially less frequent than shallow crustal or CSZ intraplate earthquakes. The most recent CSZ event is believed to have occurred in the year 1700, and paleogeologic evidence suggests five to seven interplate earthquakes may have been generated along the CSZ over the last 3,500 years. CSZ Intraplate Earthquakes. CSZ intraplate earthquakes occur within the subducting Juan de Fuca Plate between depths of 40 and 60 kilometers within the Puget SOlmd area. The Olympia 1949 (M = 7.1), the Seattle 1965 (M = 6.5), and the February 28, 200 I Nisqua1ly (M = 6.8) earthquakes are considered to be intraplate earthquakes. The CSZ. intraplate source zone is characterized by researchers as being capable of generating earthquakes up to magnitude 7.5. The recurrence interval for large earthquakes· originating from the CSZ intraplate source zone is believed to be shorter than for the sha1Iow crustal and File No. 0691'()S9'()O October is. 2004 Page C-l GeoEHGINEERS ..0 CSZ interplate source zones. However, the deep focal depth of these earthquakes tends to dampen the shaking intensity somewhat Peak Ground Acceleration The peak hOrizontal ground acceleration (FGA) is one of the primary parameters used to defme the design shaking levels. The United States Geological Smvey (USGS) bas developed probabilistic seismic hazard maps for the region that present PGA's for risk levels corresponding to events with a 10,5 and 2 percent chance of exceedance in 50 years (Frankel, et aI., 1996, 2002). The USGS PGA values are for very stiff soillbedrock sites and do not include the effects of soil amplification/dampening. According to USGS, the probabilistic PGA's for the two design levels of shaking identified for the 565 Pressure Reservoir project site are as shown in Table 1. Table 1. USGS Peak Ground Accelerations (bedrock) The USGS seismic hazard maps also include a deaggregation module, which presents the relative contribution from the three regional source zones to the probabilistic ground motions. For the 565 Pressure Reservoir site, all three source zones contnbute to the probabilistic ground motion with the shallow crustal zone contnbuting more than the intraplate or interplate for each risk level. Time histories representative of each of these source zones were used for assessing the site specific seismic response. Earthquake Acceleration Time Histories Earthquake acceleration time histories used to evaluate the site response were selected based on the fault mechanism of the earthquake source zone, the soillrock profile type at the site where the earthquake time history was recorded, the distance from the epicenter to the recording site, the PGA of the record, the predominate period, and the earthquake magnitude. Ideally, the parameters of the time histories used for analyses correspond closely to the site conditions. Table 2 presents the earthquake acceleration time histories used in our analyses. These recordings were selected based on their compatibility with the screening criteria described above. Whittier 1987 FIhI No. 069.fJ59..fJO October JJ. 2004 Table 2. Earthquake Acceleration TIme Histories Mt. Wilson Caltech Seismic Station 6.1 Page C-2 0.17 Methodology/Analyses The ground response analyses were perfonned with the computer program ProShake Version 1.1 0 (EduPro Civil Systems, Inc., 1999) using the selected earthquake acceleration time histories scaled to the design bedrock PGA values. The engineering behavior of the site soils during a seismic event was modeled using the shear wave velocity and the unit weight of the soil along with damping and shear modulus reduction relationships typical for the soil types underlying the site. The deepest exploration completed at the site extends to an approximate depth of 70 feet and was terminated in glacially consolidated silty sand soils. The contact. between the overlying glacially consolidated soils and bedrock was modeled at 150 feet based on depth to bedrock estimates presented by Yount et. ai, 1985. The shear wave velocities of the soil located within the exploration depth were estimated based on correlation with the blow counts obtained during drilling at the site. Table 3 summarizes the initial, small strain, dynamic, soil properties used in the ProShake model. Table 3. Dynamic Soil Properties Ot020 Silt 115 900 20 to 40 Silty Sand 125 1200 40 to 150 Silty Sand 125 1350 Response Spectra Response spectra for 5 percent structural damping for each of the two risk levels were developed for the site by propagating the earthquake acceleration time histories presented in Table 2 through the soil profile defmed in Table 3 using ProShake. Orthogonal pairs for each of the eight records were used to assess site response for the two risk levels resulting in 16 evaluations for each risk level. The input time histories (from recording stations on bedrock) were scaled to the bedrock PGA corresponding to the design risk level being evaluated (see Table I). The dominant component of each of the acceleration time histories was scaled to the design PGA, and their orthogonal component was scaled based on the ratio of the design PGA to the recorded PGA for the dominant component (e .g. if the dominate component had to be scaled by a factor of 12 to match the design bedrock PGA, the orthogonal pair was also scaled by a factor of 1.2). The response spectra from the eight design earthquake acceleration time histories are presented in Figures C-l and C-2 for the 10 percent in 50-year and the 2 percent in 50-year risk levels, respectively. Figures C-l and C-2 also present the resulting average response spectra (both orthogonal components were used to calculate the average) determined from the ProShake analyses along with the IBC 2003 design response spectra for Soil Site Class C. The average response spectra generally is less than the IBC Soil Site Class C design spectra. We recommend that the IBC Soil Site Class C design spectra be used for design. File No. 069·059-00 October 15, 2004 Page C-3 GeoENGINeER~ .5 o - 2 1.8 I 1.6 1.4 o 1 MexIco 1985 IN-S.I [SI ---Ch,1e 1965 <E-WI [51 ---MexIco Las Vtgas (N-St {II ---Lorna Prieta iE·Wi [Cj San Femando IN-SJ (CJ WhIttier Narrow tE-W! [Cj [C] = Crustal Earthquakes Acceleration Reeponse Spectra (10% In 50 years) 2 Period (secondsl Mexico 1985 lEW; [SI ---. N1squally tN-51 [II 3 ---MeXICO Las Vigas (E-WJ (I] .. __ . Nonhndge IN·S, [C[ ---San Fernando IE-Wi [C) -Iscse 4 Chile <985 <N-SI [5] ---Nlsq\Jalty iE-W) [Ii - Lorna Pneta IN-S; [C] Northndge iE·W) iCJ Whittier Narrow 1N·S', [CJ Avetage [~ = Intraplate Earthquakes [S] = Subduction Earthquakes 5 5% Damped Acceleration Response Spectra Figure C·1 " " 5l .S N ! ~ I a: S iii ~ ~ ~ ~ I! ~ 2.5 2 3 1.5 ~ I II> 0.5 Acceleration Response Spectra (2% in 50 years) MexIco 1985 /N-S, [SI --Chile !985,E-W:'iSj ---MexIco Las IJlgas iN-SI fll Lorna Prieta iE,\"1"I [e] San Ft!rnando IN-SI [t] Wh!!ller Narrow IE-W) (q 2 3 Period (seconds) MexIco 1985 fE·INI lSI NISGt....3ih .. I'N-S! [I] ---M€(jcc L<;i5 Vigas IE-WI [11 Ncnnr":;ge \N-$. [CJ Sa:l r.-!!~r,af1·JO fE-vVl {C] ':""erage Chile 1985 (N·S', [51 ---N1squally \E-Wllll ---Loma Pflela I N·S) [Cl NCrlhndge IE-WI [Cj Whlr'!ier Narrow IN-51 [C] -IBC SC MCE Spect~ljm [C) = Crustal Earthquakes [I) = Intra~ate Earthquakes IS) = Subduction Earthquakes 5 ~~------------------~------------------~ g en l!l GEoENGINEERS III _SCltln .. +T .... ....., 5% Damped Acceleration Response Spectra Figure C-2 3Sn HOd S3NI13Gmf) GN'ff SNOll 'rtlIWl1 lHOd3~ a X/ON3ddt!· ~ .. · . · . .. · , ., , · . .,..,... APPENDIX D REPORT LIMITATIONS AND GUIDELINES FOR USE1 This appendix provides information to help you manage your risks with respect to the use of this report. GEOTECHNICAL SERVICES ARE PERFORMED FOR SPECIFIC PURPOSES, PERSONS AND PROJECTS . This report has been prepared for the exclusive use of the City of Renton, RW Beck and their authorized agents. This report may be made available to prospective contractors for their bidding or estimating purposes, but our report, conclusions and interpretations should not be construed as a warranty of the subsurface conditions. The information contained herein is not applicable to other sites. GeoEngineers structures our services to meet the specific needs of our clients. For example, a geotechnical or geologic study conducted for a civil engineer or architect may not fulfill the needs of a construction contractor or even another civil engineer or architect that are involved in the same project. Because each geotechnical or geologic study is unique, each geotechnical engineering or geologic report is unique, prepared solely for the specific client and project site. Our report is prepared for the exclusive use of oUr Client and their authorized agents. Within the limitations of scope, schedule and budget, our services have been executed in accordance with our Agreement with the Client and generally accepted geotechnical practices in this area at the time this report was prepared. This report should not be applied for any purpose or project except the one originally contemplated. A GEOTECHNICAL ENGINEERING OR GEOLOGIC REPORT Is BASED ON A UNIQUE SET OF PROJECT-5PECIFIC FACTORS This report has been prepared for the 565 Pressure Zone Reservoir in Renton, Washington. GeoEngineers considered a number of unique, prOject-specific factors when establishing the scope of services for this project and report. Unless GeoEngineers specifically indicates otherwise, do not rely on this report if it was: • not prepared for you, • not prepared for your project, • not prepared for the specific site explored, or • completed before important project changes were made. For example, changes that can affect the applicability of this report include those that affect: • the function of the proposed structure; • elevation, configuration, location, orientation or weight of the proposed structure; • composition of the design tearn; or • project ownership. 1 Developed based-on material provided by ASFE. Professional Finns Practicing in the Geosciences; www.asfe.org. File No. 0693-059-00 October 15, 2004 PageD-1 GEoENGINEERSg SUBSURFACE CONDITIONS CAN CHANGE This geotechnical or geologic report is based on conditions that existed at the time the study was performed. The findings and conclusions of this report may be affected by the passage of time, by manmade events such as construction on or adjacent to the site, or by natural events such as floods, earthquakes, slope instability or groundwater fluctuations. MOST GEOTECHNICAL AND GEOLOGIC FINDINGS ARE PROFESSIONAL OPINIONS Our interpretations of subsurface conditions are based on field observations from widely SpaCed sampling locations at the site. Site exploration identifies subsurface conditions only at those points where subsurface tests are conducted or samples are taken. GeoEngineers reviewed field and laboratory data and then applied our professional judgment to render an opinion about subsurface conditions throughout the site. Actual subsurface conditions may differ, sometimes significantly, from those indicated in this report. Our report, conclusions and interpretations should not be construed as a warranty of the . subsurface conditions: GEOTECHNICAL ENGINEERING REPORT RECOMMENDATIONS ARE NOT FINAL Do not over-rely on the preliminary construction recommendations included in this report. These reconunendations are not final, because they were developed principally from GeoEngineers' professional judgment and opinion. Geotechnical recommendations can be finalized only by observing actual subsurface conditions revealed during construction.· GeoEngineers cannot assume responsibility or liability for this report's recommendations if we do not perform construction observation. Sufficient monitoring, testing and consultation by GeoEngineers should be provided during construction to confinn that the conditions encountered are consistent with those indicated by the explorations, to provide recommendations for design changes should the conditions revealed during the work differ from those anticipated, and to evaluate whether or not earthwork activities are completed in accordance with our recommendations. Retaining GeoEngineers for construction observation for this project is the most effective method of managing the risks associated with unanticipated conditions. A GEOTECHNICAL ENGINEERING OR GEOLOGIC REPORT COULD BE SUBJECT To MISINTERPRETATION Misinterpretation of this report by other design team members can result in costly problems. You could lower that risk by having GeoEngineers confer with appropriate members of the design team after submitting the report. Also retain GeoEngineers to review pertinent elements of the design team's plans and specifications. Cimtractors can also misinterpret a geotechnical engineering or geologic report. Reduce that risk by having GeoEngineers participate in pre-bid and pre construction conferences, and by providing construction observation. Do NOT REDRAW THE EXPLORATION LOGS Geotechnical engineers and geologists prepare final boring and testing logs based upon their interpretation of field logs and laboratory data. To prevent errors or o1irissions, the logs included in a geotechnical engineering or geologic report should never be redrawn for inclusion in architectural or other design drawings. Only photographic or electronic reproduction is acceptable, but recognize that separating logs from the report can elevate risk. File No. 069-()59-00 October /S, 2004 PageD-2 GEoENGINEER~ GIVE CONTRACTORS A COMPLETE REPORT AND GUIDANCE Some owners and design professionals believe they can make contractors liable for unanticipated subsurface conditions by limiting what they provide for bid preparation. To help prevent costly problems, give contractors the complete geotechnical engineering or geologic report, but preface it with a clearly written letter of transmittal. In that letter, advise contractors that the report's accuracy is limited; encourage them to confer with GeoEngineers andlor to conduct additional study to obtain the specific types of information they need or prefer. A pre-bid conference can also be valuable. Be sure contractors have sufficient time to perform additional study. Only then might an owner be in a position to give contractors the best information available, while requiring them to at least share the financial responsibilities stemming from unanticipated conditions. Further, a contingency for unanticipated conditions should be included in your project budget and schedule. CONTRACTORS ARE RESPONSIBLE FOR SITE SAFETY ON THEIR OWN CONSTRUCTION PROJECTS Our geotechnical recommendations are not intended to direct the contractor's procedures, methods, schedule or management of the work site. The contractor is solely responsible for job site safety and for managing construction operations to minimize risks to on-site personnel and to adjacent properties. READ THESE PROVISIONS CLOSELY Some clients, design professionals and contractors may not recognize that the geoscience practices (geotechnical engineering or geology) are far less exact than other engineering and natural science disciplines. This lack of understanding can create unrealistic expectations that could lead to disappointments, claims and disputes. GeoEngineers includes these explanatory "limitations" provisions in our reports to help reduce such risks. Please confer with GeoEngineers if you are unclear how these "Report Limitations and Guidelines for Use" apply to your project or site. GEOTECHNICAL, GEOLOGIC AND ENVIRONMENTAL REPORTS SHOULD NOT BE INTERCHANGED The equipment, techniques and personnel used to perfonn an environmental study differ significantly from those used to perform a geotechnical or geologic study and vice versa. For that reason, a geotechnical engineering or geologic .report does not usually relate any environmental fmdings, conclusions or recommendations; e.g., about the likelihood of encountering underground storage tanks or regulated contaminants. Similarly, environmental reports are not used to address geotechnical or geologic concerns regarding a specific project. BIOLOGICAL POLLUTANTS GeoEngineers' Scope of Work specifically excludes the investigation, detection, prevention, or assessment of the presence of Biological Pollutants in or around any structure. Accordingly, this report includes no interpretations, recommendations, findings, or conclusions for the purpose of detecting, preventing, assessing, or abating Biological Pollutants. The term "Biological Pollutants" includes, but is not limited to, molds, fungi, spores, bacteria, and viruses, andlor any of their byproducts. File No. 069-059-0Q October J 5. 1004 PageD-3 GEoENGJNEERS~ Hazen Reservoir Prepared for: City of Renton Prepared by: 10555 Grady Way 5th Floor Renton, WA 98055 Bothell East Wenatchee Port Orchard Bellingham Tacoma 800.720.8052 RH2 Project: REN 105.049.01.102 Prepared: Winter 2007 TECHNICAL INFORMATION REPORT H.uen Reservoir -----=c~__, 'EX_PlRESJ/14108 Prepared by: RI-l2 Engineering, Inc. (800) 720-8052 Winter 2007 11/11/07 EXPIRES I Oil toB 11/11/07 Section 1.0 - Section 2.0 - Section 3.0 - Section 4.0 - Section 5.0 - Section 6.0 - Section 7.0 - Section 8.0 - Section 9.0 - Section 10.0 - Technical Infonnation Report City of Renton Hazen Reservoir TabJe of Contents Project Overview ............................................................................................................. 1 Conditions and Requirements Summary ................................................................. 1 Off-site Analysis ."" ................................................................ __ . __ .................................... 1 Flow Control and Water Quality Facility Analysis and Design .... ____ ................. 3 Conveyance System Analysis and Design .............. __ ...... ______ .. ________ .......... __ ............. 6 Special Reports and Studies ................... __ ...... __ ......................................... __ ................. 7 Other Permits ____ .......................................... __ .... '" __ . __ .. __ .......... __ ................ __ ....... __ . __ ......... 7 Construction Stonnwater Pollution Prevention Plan Analysis and Design __ ' 7 Bond Quantities, F aciliry Summaries, and Declaration of Covenant... ......... __ 7 Operations and Maintenance Manual. __ ................................................. __ ................ 8 Appendix A -Worksheets and Fonns Appendix B -KCRTS and Stonn Calculations Appendix C -FEMA Map Appendix D -Off-site Analysis Appendix E -Conveyance System Calculations Appendix F -Operation and Maintenance Manual © RI12 Engineering, Inc., 2(X)6 1/IS/21K17 2:]8:5n Pi\{ J;\dala \RFN\ 105-().j.'J\r>c~1W'\.storm\ 11R\ hdl Infu Rcpondoc Technical Information Report Winter 2007 Section 1.0 -Project Overview City of Renton Hazen Reserooir The City of Renton is adding a second water reservoir in the City's 565 Pressure Zone to ensure sufficient storage for normal and emergency uses and to allow the existing reservoir to be taken out of service for maintenance. RW Beck, Inc. previously prepared the predesign report that evaluated three alternative sites for the reservoir's location. The selected alternative was a standpipe located on property owned by the City south of Sunset Boulevard and west of 142nd Avenue SE. RH2 was selected by the City to provide engineeting services for the design of the reservoir, including site design and surface water management. A site survey and a geotechnical report for that property was completed as part of the predesign and this information has been provided to RH2 for their use in designing this project. The existing property is owned by the City of Renton and encompasses approximately 8.7 acres (according to the survey data). It is located in T23N RSE Section 3 SE '/. SW '/. WM, and is accessed by Southeast 112th Street, a private gravel road. The parcel number is 0323059061 and the site address is 140XX Southeast 112th Street, Renton, Washington 98059. The site is undeveloped, except the gravel access road that runs through it, and is bounded on the south by Hazen High School, on the west by an athletic field for the school, on the east by single~family homes and on the north by Southeast Renton~Issaquah Road (Sunset Highway -Primary State Highway No.2). Honey Creek runs through the northern portion of the property. Refer to the cover page of the plan set for a vicinity map. The Technical Information Report (rIR) Worksheet are located in Appendix A. A Geotechnical Report, tided Geotec/miml Iingineering Semees 565 Pressure Zone Reserooir Renton, Washington, has been prepared by GeoEngineers, Inc. for this project site and included with the submittal package for additional soils information. Section 2.0 -Conditions and Requirements Summary The subject property is located within the city limits of the City of Renton; therefore, the governing drainage code is that of the City of Renton. According to the City Planning Department, the King Coullty SIIr/tHe lPater Design Manila/, 2005 edition (KCSWDM) is the design manual for the City. The project proposes to construct approximately 0.71 acres of new impervious surface in the form of a new water reservoir, paving and gravel access roads. In reviewing the flow chart in KCSWDM Figure 1.1.2 . .1\, the project is subject to Full Drainage Review because it will result in greater than 2,000 square feet of new impervious surface. Section 3.0 -Off-site Analysis Upstream The basin draining to the project site has been identified and shown in Appendix B. The offsite upstream area tributary to the project site is estimated to be approximately 0.31 acres, and surface water from the upstream basin reaches the project site via sheet flow. It is not anticipated the proposed project will create significant flooding or erosion © RI12 En,l.,rinccring, Inc., 2(K16 1 /lS/2tJ072,3851J PM 1 J: \data \REN\ t()5-049\Dc~ign \Storm \HR \TL"i:h Info Report.doc Ciry of Renton H a<fn Reserooir Technical Information Report Winter 2007 to it. From this information, a runoff time series was created to estimate peak flows for the basin. Please refer to the calculations in Appendix B. The following table summarizes the results. Return Period Peak (years) Flow (efs) tOO 0.06 25 0.04 to 0.03 5 0.03 2 0.03 An analysis was performed for the developed conditions of the project site to determine that the tOO-year peak flow from the project site is 0.38 cfs. Therefore, in accordance with KCSWDM Section 1.2.3.2.F, it is acceptable for the upstream tributary area to flow through the proposed detention facility. Downstream A Levell Analysis (qualitative analysis) was completed for this project. Resource View -Adopted basin plans, fmalized drainage studies, Basin Reconnaissance Summary Reports, other off-site analysis reports in the same subbasin and/or migrating river studies are not known to exist for the project drainage area. The City of Renton did not indicate any drainage complaints or road drainage problems downstream of the project site. Floodplain/floodway (FEMA) maps were reviewed and indicate the site in Zone X, which are areas determined to be outside the 500-year floodplain. The FEMA map for the project site is located in Appendix C. According to the City of Renton mapping, the proposed project does not lie within identified areas for coal mine hazard, erosion hazard, flood hazard or seismic hazard. The proposed project does lie within Aquifer Protection Zone 2. Critical areas exist on the project property, but are 500 linear feet away from the proposed project site. Honey Creek crosses the property at the north edge of the site and wetlands associated with the creek exist adjacent to it. Honey Creek is a Category 4 stream. Field Inspection and Drainage System Description -Surface water runoff from the project site travels north within the boundaries of the property down the slope toward Honey Creek. Runoff becomes tributary to Honey Creek near the north edge of the property (Honey Creek runs east-west across the property). Honey Creek then travels west through a residential development area and continues until it reaches Duvall Avenue. At Duvall Avenue, the Creek enters a closed-pipe system where it is conveyed beneath an existing parking lot for a commercial area. The Creek continues in a westerly direction in pipes and crosses under Southeast Renton-Issaquah Road (Sunset Highway - Primary State Highway No.2) in a west-northwest fashion. The Creek discharges from o RlJ2 Engineering, Inc" 2006 1/15/2007203850 PM 2 J:\data \REN\105~049\Design\St()nn\ llR\Tcch Tnfo Rc..-port.doc Technical Information Report Winfer2007 City of Renton H a'(fn Reservoir the pipe system at a 42-inch diameter pipe approximately 400 feet east of Union Avenue (a.k.a. 132"d Avenue Southeast) on the north side of Southeast Renton-Issaquah Road. The Creek then travels the 400 feet west where it is collected by two 42-inch diameter culverts for conveyance under Union Avenue for discharge on the west side of Union Avenue. The Creek then continues from this point in a northwest fashion, traveling between Southeast Renton-Issaquah Road (south side) and residential homes (north side). It continues on westerly and is eventually tributary to Lake Washington. Refer to Appendix D for photos from the site reconnaissance and a map showing the location and direction of the pictures taken. Existing drainage problems were not identified during the downstream analysis. Signs of erosion, scour or capacity problems were not visible. It is not anticipated the proposed project will have adverse effect on the downstream system. Section 4.0 -Flow Control and Water Quality Facility Analysis and Design The Existing Site Hydrology constitutes 0.91 acres of till soils. The soils were modeled using forested land cover. The following schematic summarizes the flow characteristics for the existing site. Off-site Tributary Predeveloped On-site f<low The following table surnmari,es the off-site tributary and predeveloped on-site areas. Existing and Off-site Tributary (predev.tsI) Land Cover Offsite Tributary Till I'otest Offsite Tributary' rill Pasture Offsite Tributary Impervious Onsite Till Forest Total © RIT2 Engineering, Inc., 2006 1/15/20072:38:50 PM 3 Area (acl 0.151 0.072 0.086 0.906 1.214 J:\data \RI·:N\ 1()5-049\Dc~jgn\5t()nn\1'IR\'rcch Info Rt.porLuoc Ciry of Renton Ha"en Reservoir Technical Information Report Winter 2007 The devdoped site hydrology consists of the disturbed areas to be landscaped/ hydroseeded, the reservoir, future booster station, future utility pad, paved driving and parking surfaces. All of the disturbed areas of the project site will be directed to the proposed stormwater pond, except some minor hydroseeded areas. The following schematic summarizes the flow characteristics for the devdoped site. Off-site Tributary Devdoped On-site Developed On-site Bypass Detention Pond The following table summanzes the off-site tributary and developed on -site areas, followed by the developed on-site bypass area. Developed and Off-site Tributary to Detention (rdin. tsf) Land Cover Offsite Tributary Till Forest Offsite Tributary Till Pasture Offsite Tributary Impervious On site Till Grass Onsite Impervious Total Develo Land Cover Bass -Till Grass Total © RH2 Engineering, Inc., 2006 1/15/2!Kl7HS,SO PM Mea (ac) 0.151 0.072 0.086 0.160 0.707 1.175 0.039 0.039 4 J: \data \REN\ 105-049\De&igtl \Stann \ 11R\ Tech Info Rl.-port.doc Technical Information Report Winter 2007 City of Renton Hazen ReJe1wir A drainage analysis was performed using the King County Runoff Time Series Program (KCRTS) with a regional scalc factor of 1.0, as interpolated from Figure 3.2.2.A of the KCSWDM. The areas were entered into the KCRTS program to create time series ftles. KCRTS was then used to calculate peak flows and durations, along with a target duration for matching the threshold discharge arca to 50 percent of the 2-year peak flow up to the 50-ycar pcak flow during existing conditions. A reservoir ftle containing stage-storage- discharge data was created in KCRTS based on volume information generated from AutoCAD and orifice flows from functions in KCRTS. The performance of the proposed detention pond was analyzed by routing developed and off-site tributary time series file (rdin.ts£) through the reservoir to create the reservoir outflow time series fue (rdout. ts£). The on-site bypass area (bypass. ts£) was then added to the reservoir outflow time series fue (rdout.ts£) to get the point of compliance time series ftle (dsoutts£). This point of compliance time series was then analyzed to determine the flow durations and exceedance values. This was then plotted against the flow durations and exceedance values of the target values developed from the predevc10ped time scties (for 50 percent of the 2-year peak flow up to the 50-year peak flow). The bypass flow durations and exceedance values are also shown on the graph for reference. All of the data entered into KCRTS, the KCRTS output and stormwater analysis can be located in Appendix B. The proposed pond's capacity is 46,200 cubic feet before an overflow dcvice in the control structure is used within the pond. The pond storage used to meet the minimum stormwater requirements is approximately 16,300 cubic feet for the 50-year design event. This leaves approximately 29,900 cubic feet of storage available in the pond for a reservoir overflow event that could occur during the 50-year design storm. Assuming a pump is stuck "on" and causing overflow of 4,000 gpm (8.91 cfs) to the pond, and approximately 0.1 cfs (45 !''Pm) leaving through thc pond's control structure, we estimate the 29,900 cf will provide approximately 57 minutes of response time before thc reservoir overflow would cause a storage pond overflow. The City must respond to a reservoir overflow situation within that 57 minutes or significant downstream damage may occur if water overflows at the pond's emergency overflow spillway. The existing conditions 100-year peak flow is 0.13 cfs, and the developed conditions pond 100-ycar peak outflow is (j.07 cfs. In accordance with KCSWDM Section 1.2.1, it is acceptable for the pond outfall pipe to be discharged onto a rock pad. However, it is preferred for the outfall pipe to discharge to a level spreader to distribute flow and minimize chances of point source erosion at the outfall pipe. An emergency overflow spillway has been designed and incorporated into the pond wall as identified on the design plans. The spillway has been sized to pass the reservoir overflow event of 8.91 cfs. After discussions with the City staff, a formal conveyance system downstream of the overflow spillway has not been designed. This is due to the unlikely event of a reservoir overflow overtopping the pond, the environmental damage thc conveyance system would cause and the added cost to the public for design, permitting and construction of that conveyance system. The City has indicated that in the last ten years, omy one reservoir overflow has occurred and it was responded to in less than 57 minutes. to RI 12 Engim.:r.::nng, Tnc., 2006 1/15/200n3R5() PM 5 J: \data \ RI':N\ 1 05-049\Dcsign \Stonn \'1 'IR \'J'cch Info )h:port.doc City uf Renton H az,en Reservoir Technical Information Report Winter 2007 A formal stormwater quality control facility is not proposed for this project since the proposed conditions of the site will not contain pollution generating surfaces by definition (see KCSWDM Chapter 1 Defmitions). The impervious surfaces will not be subject to vehicular trafftc beyond occasional maintenance vehicle access to the site (estimated at once per week during the year and two-to-three times per week during summer months). Therefore, the City requests an exemption from providing a formal water quality control facility. The ftnal site will be stabilized using paving, gravel, vegetation and quarry spalls to prevent sediment from leaving the site in surface water runoff. After reviewing options for source control using guidance from the Stormwatcr Management Manual for Western Washington prepared by the Department of Ecology, it was determined that the proposed use of the project site does not conform to those identified in the manual and, hence, standard source control measures were not available. Based on the proposed use of the project site as a water storage tank and future booster pump station, it is not anticipated that the uses will create a situation where significant sources of pollution will be present and able to enter the stormwater system. Therefore, source control measures beyond maintaining the ground cover around the site (identified in the Operations and Maintenance Manual) are not proposed. Section 5.0 -Conveyance System Analysis and Design KCRTS was used with 15-minute time steps to determine the peak flow for the project site (Inclusive of the tributary upstream area). The longest unconcentrated flow path for the till grass results in a length of 34 feet and an average slope of 7.4 percent. The longest unconcentrated flow path for the impervious results in a length of 90 feet and an average slope of 2.2 percent. In accordance with Section 1.2.4.1 and Table 3.2 of the KCSWDM, it is acceptable to design the conveyance system using the peak flows from the 15-minute time steps for the 25-year event. The conveyance system is capable of conveying the required 0.97 cfs, which is the 25-year peak flow using the 15-minute time steps. The conveyance swale around the perimeter of the proposed water tank will have 3-to-1 side slopes, an overall depth of 1.25 feet and a minimum slope of 0.5 percent. For conservancy, the swale was analyzed with a 0.25-foot freeboard, assuming the full 25- year peak flow drained to the lowest conveyance capacity swale. A Manning's value of 0.030 was selected to represent grass with weeds. The result of 0.97 cfs flow (the 25-year peak flow) is a channel depth of 0.5 feet, and the channel has a maximum capacity of 6.39 cfs. The two proposed culverts were analyzed using the conservative approach of assuming the full 25-year peak flow drained to each culvert and that the pond was ftlled to capacity (elevation 453). The culvert under the pond access road resulted in a headwater depth of 0.7 feet. The culvert under the reservoir access road resulted in a headwater depth of 0.65 feet. © RI J2 Engineering, Inc., 20()6 1/15/200723"050 PM 6 J: \clata \REN\ 1 05-049\Dc~hrn \Stonn \ l1R \ Tech Info Report-doc Technical Information Report Winter 2007 City of Renton H azrn Reservoir Although the culvert headwater depths are slighdy higher than the depth calculated for the conveyance swale (approximately 2.4 inches), a full backwater analysis of the swales and culverts is likely not warranted based on the conservatism used in the analyses as described above and the excess remaining capacity in all conveyance components. Please refer to Appendix E for the conveyance system calculations. Section 6.0 -Special Reports and Studies A geotechnical investigation was performed for the project site. Refer to the Geotechnical Engineering Services 565 Pre.wire Zone Reservoir Renton, Washington, prepared by GeoEngineers, Inc. for this project site and included with the submittal package for additional soils infonnation. Other special reports and studies were not required for this project. Section 7.0 -Other Permits It is anticipated that compliance with the Department of Ecology's NPDES General Permit for discharge of construction stormwater will be required. This will necessitate the development of a Construction Stormwater Pollution Prevention Plan. Other permits are not anticipated to be required for this project. Section 8.0 -Construction Stormwater Pollution Prevention Plan Analysis and Design The Construction Stonnwater Pollution Prevention Plan (CSWPPP) identifies specific practices that the contractor for the project must comply with. Because this project is a public works project and will be competitively bid, the CSWPPP has been generated as a separate document. The purpose for this is that it may be included as an appendix to the project specifications so that each prospective bidder will understand the requirements for the CSWPPP. The CSWPl'P complies with the requirements of the KCSWDM and uses guidance from the Department of Ecology's Stormwater Management Manualfor WeJtern Washington. Please refer to that separate document for CSWPPP infonnation. Section 9.0 -Bond Quantities, Facility Summaries, and Declaration of Covenant The proposed project is for a public agency (City of Renton), and therefore this section does not apply. © RTTZ Engineering, Inc., 2006 1/15/20072:3B:50 PM 7 J:\data\RJ':N\ l05-049\Dcsign\Storm\nn\'I'cch Info RLTHlrt.doc City ufRcnton Ha"en ReseTVoir Technical Information Report Winter 2007 Section 10.0 -Operations and Maintenance Manual The operations and maintenance manual can be found in Appendix F. The elements covered are: • Detention Ponds; • Control Structure/Flow Restrictor; • Catch Basins; • Debris Barriers; • Energy Dissipaters; • Fencing; • Gates; • Conveyance Pipes And Ditches; • Grounds (Landscaping); and • Access Roads. This concludes the Technical Information Report for the City of Renton's Hazen Reservoir Project. C> RTl2 Engineering, Inc., 2O()(1 1/15/200723850 PM 8 J: \data \REN\ 105-049\Dcsign \Stonn \'I'IR \TC(;h Info Report.doc Appendices Appendix A KING COUNTY. WASHINGTON. SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 1 PROJECT OWNER AND PROJECT ENGINEER Project Owner C \ \-~ cJ <:. Phone __________ _ Address __________ ._ Project Engineer \3, ... d-B~ c;, f ' Company R H 7.. E. "'5'£ I,' '" , .C· f' . Phone LI'Z. S. "'\S I . S' ,." ~ ~~--~~~~~~-~---- Part 3 TYPE OF PERMIT APPLICATION [J Landuse Services Subdlvison I Short Subd. I UPD [J Building Services M/F I Commerical I SFR [J Clearing and Grading [J Right-ol-Way Use til Other ~.\.,,-i-;,--li c F c... . Part 5 PLAN AND REPORT INFORMATION Tecllnlcal information Report Type 01 Drainage Revie~ Targeted I (Circle): e Site Date (include revision S· . --:~-'~~--~-~~--~b- dates): ~ (' --,',,''''.J!l::J:. Date 01 Final: - Part 6 ADJUSTMENT APPROVALS it.. Part 2 PROJECT LOCATION AND DESCRIPTION DOES Permtt # _...:N~},-,f>,,-,-____ _ Location Township -'-::30 tJ Range 5E Section 3 StteAddress I'-/OXX SE. tI"l.~ s,1- K'.UA~ VJA Part <I OTHER REVIEWS AND PERMITS [J DFWHPA [J COE<lO<l [J DOE Dam Salely [J FEMA Floodplain [J COE Wetlands [J Other [J Shoreline Management ~tural ocke aulll ESA Section 7 SIIe Improvement Plen (Engr. Plans) Type (circle one): ~ Moonied I all Site Date (include revision Si~ PL~ dates): Dale 01 Final: Type (circle one): Standard I Complex , Preapplicalion I Experimental I Blanket '7 , , Description: (include condttions in TIR Section 2) -~ ----~-~---- Date 01 Approval: - 2005 Surface Waler Design Manual 111/05 KING COUNTV. WASHINGTON. SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 7 MONITORING REOUIREMENTS Monijoring Required: ves(§) Describe: Start Date: Completfon Date: Part 8 SITE COMMUNITY .... ND DRAINAGE BASIN Community Plan : tJ fA ~~D~Ow~rt~a~~~:~T/l~-------------- Drainage Basin: -:-_-,-_,-/-~-,--______ _ Stormwater Requirements: Part 9 ONSITE .... ND ADJACENT SENSITIVE AREAS ..ra RiveriStream !d~ &u.dL [J Steep Slope ______ _ [J Lake [J Erosion Hazard _________ _ [J Wetlands [J Landslide Hazard ______ _ [J Closed Depression [J Coal Mine Hazard ______ _ [J Floodplain [J Seismic Hazard ______ _ [J Other [J Habitat Protection ______ _ [J ________ _ Part 10 SOILS Soil Type Slopes Erosion Potential 'S. E:~ /SEO R.E" AJ121 [J High Groundwater Table (wijhin 5 feet) [J Sole Source Aquifer [J Other [J Seeps/Springs [J Additional Sheets Attached 2005 Surface Wale, Design Manual 111/05 2 KING COUNTY. WASHINGTON. SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET ,----------~~~-~-----------------, Part 11 DRAINAGE DESIGN LIMITATIONS I-----------~~~-~~-~-----------------I REFERENCE I:] Core 2 -Offsile Analysis I:] SenSitive/Critical Areas I:] SEPA I:] Other LIMITATION / SITE CONSTRAINT f'Ju,"". ? ( 1:] _________ _ I-=,------------.-~--~---------------j I:] Additional Sheets AHached Part 12 TIR SUMMARY SHEET Threshold Discharge Area: (name or descrjptiori) Core Requirements <an 8 eppIy) Discharge at Natural Location Offsite Analysis ~~~~ .. ~~~~ _____________ _____.J (provide one TlR Summary Sheet per Th .... hoId DischarJIe Area) Numberof Natural Discharge Locations: 1 Tav"l: "9 2 I 3 dated: ______ _ '''(-iinc-;t::-:~-~-iliC=-t:-~-'-tr-07"lm-ary-s-he-e-t)----~:=1lisile k~ 3 or Exemption Number ----- Conveyance System Spill containment located at: Hoc 01 C.~n bu'! S h,.,.. c i '~"F- Erosion and Sediment Control Maintenance and Operation Financial Guarantees and Liability Water Quality (include lacilHy summary sheet) ESC Site Supervisor:'o \::.A.. cJv.-)r,-""'-' ...... cJ Contact Phone: b ( or.." LleJ..L . ) l Alter Hours Phone: '6 . ....-~I V'-"', "'" Responsibility: Private 1(f'Ubi1?J ~-------l If Private, Maintenance Ltv1 RAt1ulred: Yes I No Provided: Yes /~ Type: Basic I Sens. Lake I Enhanced BaSicm I Bog or Exemption No. ,J~ Pe t1u..h",,·"1<,.., v",hJ\~ ~.u.-I, us; Landscape Management Plan: Yes I (i:lq) Special Requirements I .. aDDIlcableL~~~ ...... ~"" Req~;r:~!,:,ilicDrainage.. ...... .... ~:.:~: CDA I SDO I MDP / BP I LMP I Shared Fac./~ FloOdPIainiFloOdWayDelineation Type: Major I Minor I Exemption @ 100·year Base Flood Elevation (or range): _____ _ Dalum: Describe: -;Jj;..~'-~--~--------~~~~~'~~- I-~~~~~-----~-~ Source Control Describe landuse: iNGJ c,; e..s,.v'Jo',~ (comm./industriallanduse) --~~--------- Describe any structural controls: to' G"f\..;.. 200S Surface Water Design Manual 1/1105 KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Oil Control High-use SRe: Yes I ~tJ/A Treatment BMP: M,aintenance Agreement: Yes I ~ ;c.J / A- with whom? Other Drainage Structures Describe: Part 13 EROSION AND SEDIMENT CONTROL REQUIREMENTS MINIMUM ESC REQUIREMENTS MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION AFTER CONSTRUCTION li'J Clearing Limits BStabilize Exposed Surfaces ,El Cover Measures ;::::I Remove and ResJore Temporary ESC Facilities ~ Perimeter Protection ;;Ef Clean and Remove An Sib and Debris Ensure )ji,iI Traffic Area Stabilization Operation 01 Permanent Facilities eJ Sediment Retention [J Flag Limits of SAO and open space Jla Surface Water Control preservation areas [J Other ~ Dust Control :e Construction S6quence Part 14 STORMWATER FACILITY DESCRIPTIONS {Note: Include FacilHv: and Sketchl Flow Control T ion Water Quality T n )9 Detention PoY\cl, [J Biofiltration [J Infiltration [JWetpooI [J Regional Facility [J Media Filtration [J Shared Facility [J Oil Control D Sma. SRe SMPs [J SpiU Control [J Other [J Sman SRe BMPs [J~,% 10 fA 2005 Surface Water Design Manu.1 4 KING COUNTY. WASHI:\(iTON. SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part15 EASEMENT5nRACTS Part 16 STRUCTURAL ANALYSIS o Drainage Easement o Cast in Place Vault o Retaining Wall ;il Rockery> 4' High \Y.N ~ W • ../.) ... o Access Easement o Native Growth Protection Covenant o Tract o Structural on Steep Slope o Other o Other ... + __ .. _ .. ~-L ________________ --' "'Pa=-=rt;cl""7'----'S'"IG"'N"'A"T"U"R"'E""O"'F"""PR""O"'F"'E=SSIONAL-E-NG'"IN"'E"'E""R------------------, I, or a civil engineer under my supervision. have visited the site. Actual site conditions as observed were incorporated into this worksheet and the attached Technical Information Report. To the best of my know~~tion pr~here is accurate. ~ rs::;.'""--r.-') il / \ 0 /O(a f I SignedlDat .. __ .. ___ .. ________ . ___ .....J -_ .. _._-_ ... -.-_ ... _----- 2005 Surface Water Design Manual 5 1/1105 1400 I Southeast I 12th Street, renton, WA -Google Maps Gougle oS); ....... N)~~) I '-'1") arj~ rJr· rar· .~. .,~. GreePwOOd Memorial Park Address 14001 SE 112th St Renton, WA 98059 I\t"'-:ll'~ r;Jr~ < ., 1: •. "h ." " , " " ". se I 28th St .'f _\.' "',.' ;; " Page I ofl 'v'apJe Val i H~ Q11S r a $E t2"3Ch St http://www.google.comlmaps?f-=q&h1=en&q~ 14001 +Southeast+ 112th+Street,+renton, + W... 1113/2006 Appendix B ON3E>31 --~ "3" 10 ,,01 .::il..-"'-.-['9-.-_- • <' / --'" . '" '" r I ~ ...... -q; .----...... ...- or -.1 SNIS'18 DNI!SIX3 \ ~ r ..... / / / I .J J / /' -\ .-\ \ --- I ~ '" / / I ------ ----<'" ~~, z-# L-# -_ ..I / / I '" ,/ -.J / ,f+~ ..-4, _.,) ) , I ,/ / / I ./ ( / I - --- --z.., ~/ '\. , " .. ~ ...,(- ---' /' '\ \ .. ~ \ \ \ / / / ,----I \' r- \ " ,/ ,/ ,/ I / / / / 1', I \ '\. I , ',I ( . ,/ J / ~ /' ,/ / "'~ /1) / ,/ ./ ..- '" I f / ,/ / / -' \C;'r - ----..,. r / / I / I ----- ---' ........ ..-'\ '\. , ..-/ \ / /----\ ./ /' , /./ ..-' /'0'" ~ _ _ , " r:-/ I ~.' ) (j "l I " '\ \ ( ~/ f ___ \\\ / I 1/ \\'\. / I I I r C;'rY -"\', I', \ 111// ") \ -\ \ \ \ \ \\ ., / I ., I I I / I ........ -- '---~ --LCp - / ,/ lON 51 ~V8 JI ~NOl .l SI ~N IMVil a ]w:)S 01 lON 0 / / / / I I I I I I -t .. ,:;f't ': - I I I I I I Ij I \ / I I / \ . ./ I ,or = .l SNIS"8 03S0dOHd • - ON3D31 .--' /' '" . I /' . ! I I ( / -/--- • '\. '\. , '-~ ~"---- ------r--Z~---" ! 'c: S' .. .-- / I / ./ /' '\. I "" '" /' /' -/ ,/ /--- '- / -' #'''' / .. I/'\ "\ I ~ / /' ~--, \ ! / b~" I ~\..... ) \ / I I / _""" ( j I _ . \ \ \ \ I • .-- ----~--.. ---"., ....... /-. - /,"" /--...... - ( j/ ..-1 - ./ --'"""- / /' ---- / I <t>,1 1 /'~ 1 /' I 1 1 I ~ r ---Lf / 1 • I . I I 1 1 I \ I 1 -" 1 1 \" I /' '\. /' l \ ... .--/1) / \ ?-~.!\ \ f / i \ \ 1 \ ) -__ ,+t..~ , / I I ,- I I I I · /' f :l ..- I I J If I I i I I J I I I I I I / I I / I I f / I II \ I / I I I f I I / I I I I Iff I ~ 1,,;,/ I 1 I f I '/ ~ . I I / I I j , I I " I , ------------------- City of Renton Hazen Reservoir REN 105.049 Calculations for Upstream Flow-Through of the Detention Facility Prepared by RH2 Engineering Offsite Tributary (upstream.tst) Land Cover Area (ae) Offsite Tributary Impervious 0.086 Offslte Tributary Till Forest 0.151 Offslte Tributary Till Pasture 0.072 Total 0.308 Developed (site-dev.tst) Land Cover Area (ae) Onslte Impervious 0.707 Onslte Till Grass 0.160 Bypass -Till Grass 0.039 Total 0.906 Upstream Tributary 100-Yr Peak Flow = Developed Site 100-Yr Peak Flow = Upstream 100-Y r to Developed 100-Y r = 0.06 cfs 0.38 cfs 16% The 100-year peak flow rate from the Upstream Tributary area (0.06 cfs) is less than 50% of the 1 ~O-year developed peak flow rate (undetalned. 0.38 cfs • 50% = 0.19 cfs) for the area that Is to be mitigated. therefore It is acceptable to have the upstream area flow through the proposed water quantity control facility. (KCSWDM Section 1.2.3.2.F) J:lOataIRENll05·Q491DeslgnISlormITIRISlorm Cales.xls: Flow·TIlru upstream.pks Flow Frequency Analysis Time Series File:upstream.tsf Project Locatlon:Sea-Tac ---Annual Peak Flow Rates--------Flow Frequency Analysls------- Flow Rate Rank Time of Peak -Peaks Rank Return Prob (CFS) (CFS) Period 0.031 5 2/09/01 2:00 0.060 1 100.00 0.990 0.023 7 1105/02 16:00 0.035 2 25.00 0.960 0.035 2 2127/03 7:00 0.033 3 10.00 0.900 0.022 8 8126/04 2:00 0.031 4 5.00 0.800 0.026 6 10128/04 16:00 0.031 5 3.00 0.667 0.033 3 1118/06 16:00 0.026 6 2.00 0.500 0.031 4 10126/06 0:00 0.023 7 1.30 0.231 0.060 1 1109/08 6:00 0.022 8 1.10 0.091 Computed Peaks 0.052 50.00 0.980 Page I, Monday, November 06, 2006, 5:12:34 PM site-dev.pks Flow Frequency Analysis Time Series File:site-dev.tsf Project Locatlon:Sea-Tac ---Annual Peak Flow Rates--------Flow Frequency Analysls------- Flow Rate Rank Time of Peak -Peaks Rank Return Prob (CFS) (CFS) Period 0.189 6 2109/01 2:00 0.376 1 100.00 0.990 0.160 8 1/05/02 16:00 0.262 2 25.00 0.960 0.226 3 12108/02 18:00 0.226 3 10.00 0.900 0.180 7 8126/04 2:00 0.215 4 5.00 0.800 0.215 4 10128/04 16:00 0.202 5 3.00 0.667 0.202 5 1118/06 16:00 0.189 6 2.00 0.500 0.262 2 10126/06 0:00 0.180 7 1.30 0.231 0.376 1 1/09/08 6:00 0.160 8 1.10 0.091 Computed Peaks 0.338 50.00 0.980 Page 1. Monday. November 06. 2006. 5:13:21 PM City of Renton Hazen Reservoir REN 105.049 Calculations for KCRTS Areas Prepared by RH2 Engineering ExIsting and OtTslte Tributary (predev.tsf) Land Cover Area (ac) Offslte Tributary Till Forest 0.151 Offsite Tributary Till Pasture 0.072 Offsite Tributary Impervious 0.086 Onsite Till Forest 0.906 Total 1.214 Developed and Off site Tributary to Detention (rdln.tsf) Land Cover Area (ac) Offsite Tributary Till Forest 0.151 Offsite Tributary Till Pasture 0.072 Off site Tributary Impervious 0.086 Onsite Till Grass 0.160 Onsite Impervious 0.707 Total 1.175 Developed Site Bypass (bypass.tsf) Land Cover Area (ac) Bypass -Till Grass 0.039 Total 0.039 J:lDataIRENI105·049IDeslgnISlormITIRISlorm Calcs.xls: Areas Flow Frequency Analysis Time Series Flle:predev.tsf Project Location:Sea-Tac ---Annual Peak Flow Rates--- Flow Rate Rank Time of Peak (CFS) 0.085 2 2/09/01 15:00 0.037 7 1105/02 16:00 0.076 3 2/28/03 3:00 0.022 8 8/26/04 2:00 0.045 6 1105/05 8:00 0.074 4 1118/06 16:00 0.067 5 11124/06 4:00 0.127 1 1109/08 9:00 Computed Peaks Predev.pks -----Flow Frequency Analysls------- -Peaks Rank Return Prob (CFS) Period 0.127 1 100.00 0.990 0.085 2 25.00 0.960 0.076 3 10.00 0.900 0.074 4 5.00 0.800 0.067 5 3.00 0.667 0.045 6 2.00 0.500 0.037 7 1.30 0.231 0.022 8 1.10 0.091 0.113 50.00 0.980 Page 1, Monday, November 06, 2006, 5:25:23 PM Flow Frequency Analysis Time Series File:dev.tsf Project Locatlon:Sea-Tac ---Annual Peak Flow Rates--- Flow Rate Rank Time of Peak (CFS) 0.186 6 2109/01 2:00 0.158 8 1105/02 16:00 0.223 3 12108/02 18:00 0.179 7 8/26/04 2:00 0.214 4 10/28/04 16:00 0.198 5 1118/06 16:00 0.261 2 10/26/06 0:00 0.368 1 1109/08 6:00 Computed Peaks Dev.pks -----Flow Frequency Analysls------- -Peaks Rank Return Prob (CFS) Period 0.368 1 100.00 0.990 0.261 2 25.00 0.960 0.223 3 10.00 0.900 0.214 4 5.00 0.800 0.198 5 3.00 0.667 0.186 6 2.00 0.500 0.179 7 1.30 0.231 0.158 8 1.10 0.091 0.332 50.00 0.980 Page I, Monday, November 06, 2006, 5:25:55 PM Flow Frequency Analysis Time Series Flle:rdln.tsf Project Locatlon:Sea-Tac ---Annual Peak Flow Rates--- Flow Rate Rank Time of Peak (CFS) 0.216 6 2109/01 2:00 0.181 8 1105/02 16:00 0.257 3 2127103 7:00 0.201 7 8126/04 2:00 0.240 4 10128/04 16:00 0.231 5 1118/06 16:00 0.292 2 10126/06 0:00 0.428 1 1109/08 6:00 Computed Peaks Rdln.pks -----Flow Frequency Analysls------- -Peaks Rank Return Prob (CFS) Period 0.428 1 100.00 0.990 0.292 2 25.00 0.960 0.257 3 10.00 0.900 0.240 4 5.00 0.800 0.231 5 3.00 0.667 0.216 6 2.00 0.500 0.201 7 1.30 0.231 0.181 8 1.10 0.091 0.383 50.00 0.980 Page I, Monday, November 06, 2006, 5:26:51 PM Flow Frequency Analysis Time Series File:bypass.tsf Project Locatlon:Sea-Tac ---Annual Peak Flow Rates--- Flow Rate Rank Time of Peak (CFS) 0.004 4 2/09/01 2:00 0.002 6 1105/02 16: 00 0.004 2 2121103 7:00 0.001 8 3124/04 19:00 0.002 7 1105/05 8:00 0.004 3 1118/06 16:00 0.003 5 11124/06 3:00 0.008 1 1109/08 6:00 Computed Peaks Bypass.pks -----Flow Frequency Analysls------- -Peaks Rank Return Prob (CFS) Period 0.008 1 100.00 0.990 0.004 2 25.00 0.960 0.004 3 10.00 0.900 0.004 4 5.00 0.800 0.003 5 3.00 0.667 0.002 6 2.00 0.500 0.002 7 1.30 0.231 0.001 8 1.10 0.091 0.007 50.00 0.980 Page I, Monday, November 06, 2006, 5:27:39 PM Retention/Detention Facility Type cf Facility: Dete~t ~~ Pond Side Slope: .18 H: IV Pond Bottom Length: : 4 .00 ft Pond Bottom Width: 7 .00 :t Pond Bottom Area: ge c' sq. ft Top Area at 1 ft. FB: 12694. sq. ft 0.29: acres Effective Storage Depth: .. " ~.;)v ft Stage a Elevation: ;;';2.50 ft Storage Volume: 492~<'. cu. ft 1.~3l ac-ft Riser Head: L50 ft Riser Diameter: 18.00 inches Number of orifices: 2 ,,:J(l~ - t·)o-\c· : Orifice • Height (ft) 0.00 1.00 Dia"'D.e:er ( i:> ) Full Head Jischarge (CFS) 0.028 0.130 Pipe Diameter (in) r-..(..4,.....· ~_~~ f""'-'--$. CNfV' ......... I ~t. . .?-..J'Y'"" ~ { (' "~~.' t,.. -J_ t -: ')v." 1 2 Top Notch Weir: None Outflow Rating Curve: None 0.70 1. 6C Stage Elevation St~orage (ft) (ft) (cu. f+-I "0 , ~a(:-ft) 0.00 448.50 c. 0.000 0.01 448.51 98. 0.002 0.02 448.52 196. 0.005 0.03 448.53 294. C.007 0.04 448.54 392. 0.009 0.05 448.55 491-0.011 0.06 448.56 589. 0.014 0.16 448.66 1574. 0.036 0.26 448.76 2565. 0.059 0.36 448.86 3560. 0.082 0.46 448.96 4561. 0.105 0.56 449.06 5566. 0.128 0.66 449.16 6577 . 0.151 0.76 449.26 7592. 0.174 0.86 449.36 8613. 0.198 0.96 449.46 9638. 0.221 1.00 449.50 10050. 0.231 1.02 449.52 10256. 0.235 1.03 449.53 10359. 0.238 1.05 449.55 1056',. 0.243 1. 07 449.57 10772. 0.247 1.08 449.58 10875. 0.250 1.10 449.60 11082. 0.254 1.12 449.62 11289. 0.259 1.13 449.63 11393. 0.262 1.15 449.65 11601. 0.266 1. 25 449.75 12641. 0.290 1. 35 449.85 13686. 0.314 4.0 :...s; ..f+-... S':;...rY}(. "'-S 1 -------------------~" V Discharge Percolation Surf Area (cfs) (cis) (sq. ft) 0.000 0.00 9800. 0.002 0.00 9805. 0.002 0.00 9810. 0.002 0.00 9815. 0.003 0.00 9820. 0.003 0.00 9825. 0.003 0.00 9830. 0.005 0.00 9879. 0.007 0.00 9929. 0.008 0.00 9979. 0.009 0.00 10029. 0.010 0.00 10079. 0.011 0.00 10130. 0.012 0.00 10180. 0.012 0.00 10230. 0.013 0.00 10281. 0.013 0.00 10301. 0.014 0.00 10311. 0.016 0.00 10316. 0.018 0.00 10327. 0.022 0.00 10337. 0.027 0.00 10342. 0.033 0.00 10352. 0.038 0.00 10362. 0.040 0.00 10367. 0.041 0.00 10377. 0.050 0.00 10428. 0.057 0.00 10479. 1. 45 449.95 1473, . . 338 0.063 0.00 10530 . 1. 55 450.05 15]}2. .363 0.068 0.00 10582. 1. 65 450.15 16833. .387 0.073 0.00 10633. 1. 75 450.25 17919. .411 0.078 0.00 10684. 1. 85 450.35 189SC. :.436 0.082 0.00 10736. 1. 95 450.45 200615. J.461 0.086 0.00 10788. 2.05 450.55 2114~; . J.485 0.090 0.00 10839. 2.15 450.65 22234. J.510 0.094 0.00 10891. 2.25 450.75 2332E. J.535 0.098 0.00 10943. 2.35 450.85 24423. :.561 0.101 0.00 10995. 2.45 450.95 2552'0. :'.586 0.104 0.00 11048. 2.55 451. 05 26632. J.611 0.108 0.00 ll100. 2.65 451.15 27745. (). 637 0.111 0.00 1ll52. 2.75 451. 25 28863. ).663 0.114 0.00 11205. 2.85 451. 35 29986. :'.688 0.117 0.00 11258. 2.95 451.45 31114. J.714 0.120 0.00 11310. 3.05 451. 55 32248. '::.740 0.123 0.00 11363. 3.15 451. 65 33387. 0.766 0.125 0.00 11416. 3.25 451. 75 3453l. c.793 0.128 0.00 11470. 3.35 451.85 35681. 0.819 0.131 0.00 11523. 3.45 451. 95 36836. 0.846 0.133 0.00 11576. 3.55 452.05 37996 . 0.872 0.136 0.00 11630. 3.65 452.15 39162. 1).899 0.138 0.00 11683. 3.75 452.25 40333. ).926 0.141 0.00 11737. 3.85 452.35 41509. J.953 0.143 0.00 11791. 3.95 452.45 42691. 0.980 0.146 0.00 11845. 4.05 452.55 43870. 1.007 0.148 0.00 11899. 4.15 452.65 4507C. 1.035 0.150 0.00 11953. 4.25 452.75 46268. 1.062 0.153 0.00 12007. 4.35 452.85 47472. 1.090 0.155 0.00 12061. 4.45 452.95 48681. 1.118 0.157 0.00 12116. 4.50 453.00 49287. 1.131 0.158 0.00 12143. 4.60 453.10 505C4. 1.159 0.622 0.00 12198. 4.70 453.20 51727 . 1.187 1.470 0.00 12252. 4. 80 453.30 52955. 1.216 2.560 0.00 12307. 4.90 453.40 54188. 1. 244 3.860 0.00 12362. 5.00 453.50 55427. 1.272 5.330 0.00 12417. 5.10 453.60 56672' . 1.301 6.760 0.00 12472. 5.20 453.70 5792~ . 1.330 7.290 0.00 12528. 5.30 453.80 59177. 1.359 7.790 0.00 12583. 5.40 453.90 60438. 1.387 8.250 0.00 12639. 5.50 454.00 617CO. 1.417 8.690 0.00 12694. 5.60 454.10 62977. 1. 446 9.110 0.00 12750. 5.70 454.20 6425'0. 1. 475 9.500 0.00 12806. 5.80 454.30 65538. 1.505 9.890 0.00 12862. 5.90 454.40 66827. 1.534 10.250 0.00 129l8. 6.00 454.50 68122 . 1.564 10.610 0.00 12974. 6.10 454.60 69422 . 1.594 10.950 0.00 13030. 6.20 454.70 70728. 1.624 11. 290 0.00 13087. 6.30 454.80 72039. 1.654 11. 610 0.00 13143. 6.40 454.90 73357. 1. 684 11. 920 0.00 13200. 6.50 455.00 74679. 1.714 12.230 0.00 13257. Hyd Inflow Outflow Pe3~ Storage Sta?e Elev leu-Ft) IAc-Ft) 1 0.43 0.07 1. 63 450.13 16665. 0.383 2 0.29 0.01 o.,g 3 449.33 8357. 0.192 3 0.26 0.06 1.3·g 44~.88 13962. 4 0.24 0.01 O. 4 ~ ~ 4 8. 94 4376. 5 0.23 0.03 1 . ~: 9 1,;'; 9.59 10946. 6 0.22 0.06 1. ~ 9 "G.99 15110. 7 0.20 0.01 C. 6~ 4~:;. :'4 6407. 8 0.18 0.01 1. 01 4~9, 51 10117. Hyd R/D Facility Tributary s.es£;!."I.'oir poe Outflow Outflow Inflow ::::1c,· .... 1 0.01 0.01 .. ,. ~ ..... ,.. .,.. 2 0.01 0.00 .. '" .. '"' ~ ,;. .. ,. 3 0.C6 0.00 ,. .... ,.** ... ,.. 4 0.01 0.00 * ... *~"ir..,** 5 0.03 0.00 *"'~""'*T'" 6 0.06 0.00 ........... * ....... 1 0.01 0.00 .... *,..,.,;..;. ..... 8 0.01 0.00 ... ,.. .......... '* ---------------------------------- Route Time Series through Faci:~~y Inflow Time Series File:rdin.:sf Outflow Time Series Fi1e:rdou: POC Time Series File:dsou: Inflow/Outflow Analysis Peak Inflow Discharge: Peak Outflow Discharge: Peak Reservoir Stage: Peak Reservoir Elev: ~! ,I, 28 :,. ~';2 1.63 ';5J.13 CFS CFS Ft Ft Target 0.13 .* ..... * 0.08 ******* ******* ******* ******* ******* at 6:00 at 14 :00 Peak Reservoir Storage: 16666. ~u-Ft D.333 Ac-Ft Add Time Series:bypass.tsf Calc 0.07 0.01 0.06 0.01 0.03 0.07 0.01 0.01 on Jan on Jan 0.321 0.100 0.251 0.347 0.14 7 0.232 9 in Year 8 9 in Year 8 Peak Summed Discharge: 0.875 :::,S at 14: 00 on Jan 9 in Year 8 Point of Compliance File:dsout.ts: Flow Duration from Time Seri~s fi.l.e:rdout.tsf Cutoff Count Frequency C:".l!=' EX2eedence_Probability eFS % , % 0.001 26687 43.521 43. 52: 56.419 0.565E+00 0.003 8649 14 .105 57.626 42.374 0.424E+00 0.005 8261 13.482 71.:J7 28.893 0.289E+00 0.001 5542 9.038 8e . : 40 19.855 0.199E+00 0.009 5411 8.834 88.97? 11.021 o . 110E+00 0.011 2935 4.786 93.76'0 6.235 0.623E-01 0.013 2650 4.322 98.')87 1.913 0.191E-01 0.014 736 1.200 99.29i 8.713 0.113E-02 0.016 51 0.093 9'i.33~ 0.620 0.620E-02 0.018 77 0.126 93.:)~)6 0.494 0.494E-02 0.020 25 0.041 9'~.547 0.453 0.453E-02 0.022 21 0.044 93.59 0.409 0.409E-02 0.024 12 0.020 99.61 0.390 0.390E-02 0.026 12 0.020 9':1.63 0.370 0.310E-02 0.028 16 0.026 9'=1.6S 0.344 0.344E-02 0.030 20 0.033 93.6 :).311 0.311E-02 0.032 12 0.020 99.7 0.292 0.292E-02 0.033 9 0.015 99.7 0.277 0.271E-02 0.035 22 0.036 99.7S~~ 0.241 0.241E-02 0.037 8 0.013 99.77;' J.228 0.228E-02 0.039 7 0.011 99.1 93 0.217 0.217E-02 0.041 20 0.033 99.816 0.184 0.184E-02 0.043 9 0.015 99.83(' 0.170 0.170E-02 0.045 -, 0.011 99.34~ 0.158 0.158£-02 0.047 11 0.018 99.860 0.140 0.140£-02 C. 04 9 5 0.008 99.868 0.132 0.132£-02 C.051 12 0.020 99.887 0.113 o • 113E-02 0.052 8 0.013 99.90: 0.099 0.995£-03 0.054 14 0.023 99.923 0.077 0.766E-03 0.056 7 0.011 99.935 0.065 0.652E-03 0.058 10 0.016 99.951 0.049 0.489E-03 0.060 11 0.018 99.969 0.031 0.310£-03 0.062 3 0.005 99.974 0.026 0.261E-03 0.064 3 0.005 99.979 0.021 0.212E-03 0.066 5 0.008 99.987 0.013 0.130E-03 0.068 4 0.007 99.993 0.007 0.652E-04 Flow Duration from Time Series Fi~_e:dsout.t5f Cutoff Count Frequency cor ~xceedence Probability CFS % % 0.001 26755 43.632 4].632 56.368 0.564E+00 0.003 6159 10.044 53.676 1.6.324 0.463E+00 0.005 10591 17.272 70.947 29.053 0.291E+00 0.C07 5628 9.178 80.126 :9.874 0.199E+00 0.C09 5552 9.054 89.iB'; 10.820 C .108£+00 0.011 2943 4.799 93.973 6.021 0.602E-01 0.013 2458 4.008 97.983 2.012 0.201E-01 0.015 792 1.292 99.279 0.721 0.721E-02 0.017 62 0.101 99.380 0.620 0.620E-02 0.019 71 0.116 99.496 0.504 0.504E-02 0.021 30 0.049 99.545 0.455 0.455E-02 0.023 27 0.044 99.589 0.411 O.411E-02 0.025 12 0.020 99.609 0.391 0.391E-02 0.027 14 0.023 99.632. 0.369 0.369E-02 0.029 14 0.023 99.654 0.346 0.346E-02 0.031 19 0.031 99.685 0.315 0.315E-02 0.033 14 0.023 99.708 0.292 0.292E-02 0.035 12 0.020 99.728 0.272 0.272E-02 0.037 19 0.031 99.759 0.241 0.241E-02 0.039 8 0.013 99.7 72 0.228 0.228E-02 0.041 7 0.011 99.78·J 0.217 0.217E-02 0.043 22 0.036 99.819 0.181 0.181E-02 0.045 9 0.015 99.834 0.166 0.166E-02 0.047 8 0.013 99.847 0.153 0.153E-02 0.049 8 0.013 99.860 0.140 0.140E-02 0.051 7 0.011 99.871 0.129 o .129E-02 0.053 11 0.018 99.98ij C.111 0.111E-02 0.055 9 0.015 99.90,. 0.096 0.962E-03 0.057 13 0.021 99.925 0.075 0.750E-03 0.059 8 0.013 99.93e 0.062 0.620E-03 0.060 15 0.024 99.962 0.038 0.375E-03 0.062 4 0.007 99.969 0.031 0.310E-03 0.064 3 0.005 99.974 0.026 0.261E-03 0.066 3 0.005 99.979 0.021 0.212E-03 0.068 4 0.007 99.985 0.015 0.14 7E-03 0.070 5 0.008 9:;.993 8.007 0.652£-04 Duration Comparison Anaylsis Base File: predev.t.sf New File: dsout.tsf Cutoff Units: Discharge in CFS -----Fraction of ': ~l'",;:;:--------------Check of Cutoff Base New "Cha:1je Probability 0.023 0.66£-02 0.40E-02 -32.6 , 0.66E-02 0.028 0.50E-02 0.35E-02 -30.3 0.50E-02 0.033 0.38E-02 O.29E-02 ,-0 -":::::::. v' 0.38E-02 0.038 0.28E-02 0.23£-02 -:'2.4 0.28E-02 0.043 0.20E-02 0.19E-02 -S.8 0.20E-02 0.047 0.14E-02 D.15E-02 7. J 0.14E-02 0.052 0.10E-02 0.12E-02 18.9 0.10E-02 0.057 , 0.85E-03 0.73E-03 -13.5 ! 0.85E-03 0.062 0.57E-03 0.33E-03 -42.9 0.51£-03 0.066 0.41E-03 0.21E-03 -~8.C 0.41E-03 0.071 0.16E-03 0.16E-04 -90.0 0.16E-03 0.076 0.98E-04 O.OOE+OO -18C'.O ! 0.98E-04 0.081 0.49E-04 O.OOE+OO -2-~C.C 0.49E-04 Maximum positive excursion = O.:~C;:: c:s 4.1%) occurring at 0.049 cfs on the 3ase Ca~Q:predev.tsf and at 0.051 cfs on the New Ca~a:dsGu:.tsf Maximum negative excursio:l = C. ~)C9 c::s ~-32. 7%) occurring at 0.028 cfs on the 3ase Sa:a:predev.tsf and at 0.019 cfs on the New Data:dsou~.tsf Base 0.023 0.028 0.033 0.038 0.043 0.047 0.052 0.057 0.062 0.066 0.071 0.076 0.081 Tolerance------- New %Change 0.016 -30.8 0.019 -32.7 0.025 -23.2 0.033 -11.5 0.042 -1.6 0.049 2.5 0.053 2.3 0.056 -2.1 0.059 -4.1 0.060 -9.5 0.068 -5.0 0.070 -8.3 0.071 -12.7 City of Renton Hazen Reservoir REN 105.049 STAGE-STORAGE-DISCHARGE Table for Irregular-Shaped Pond (Live Storage) Prepared by RH2 Engineering Orifice 1 Orifice 2 0.70 diameter (inches) 1.60 diameter (inches) 'ULa, rermeau, 'ULa, Outfiow eArea Outfiow Elev (ft) Stage (ft) (ets)" Storage (cf) (sf) (cts) 448.50 0.00 0.000 0 0 0.000 448.51 0.01 0.002 184 0 0.002 448.52 0.02 0.002 280 0 0.002 448.53 0.03 0.002 376 0 0.002 448.54 0.04 0.003 472 0 0.003 448.55 0.05 0.003 568 0 0.003 448.56 0.06 0.003 664 0 0.003 448.66 0.16 0.005 1625 0 0.005 448.76 0.26 0.007 2589 0 0.007 448.86 0.36 0.008 3556 0 0.008 448.96 0.46 0.009 4526 0 0.009 449.06 0.56 0.010 5499 0 0.010 449.16 0.66 0.011 6475 0 0.011 449.26 0.76 0.012 7454 0 0.012 449.36 0.86 0.012 8436 0 0.012 449.46 0.96 0.013 9421 0 0.013 449.50 1.00 0.013 9816 0 0.013 449.52 1.02 0.014 10014 0 0.014 449.53 1.03 0.016 10113 0 0.016 449.55 1.05 0.018 10310 0 0.018 449.57 1.07 0.022 10508 0 0.022 449.58 1.08 0.027 10607 0 0.027 449.60 1.10 0.033 10805 0 0.033 449.62 1.12 0.038 11004 0 0.038 449.63 1.13 0.040 11103 0 0.040 449.65 1.15 0.041 11301 0 0.041 449.75 1.25 0.050 12295 0 0.050 449.85 1.35 0.057 13291 0 0.057 449.95 1.45 0.063 14291 0 0.063 450.05 1.55 0.068 15294 0 0.068 450.15 1.65 0.073 16299 0 0.073 450.25 1.75 0.078 17308 0 0.078 450.35 1.85 0.082 18319 0 0.082 450.45 1.95 0.086 19334 0 0.086 450.55 2.05 0.090 20352 0 0.090 450.65 2.15 0.094 21372 0 0.094 450.75 2.25 0.098 22396 0 0.098 450.85 2.35 0.101 23422 0 0.101 J:IDataIRENI105-Q491DesignlStarmITIRIStOlm Calcs.xls: Stage-Star (2) 450.95 2.45 0.104 24452 0 0.104 451.05 2.55 0.108 25484 0 0.108 451.15 2.65 0.111 26520 0 0.111 451.25 2.75 0.114 27558 0 0.114 451.35 2.85 0.117 28600 0 0.117 451.45 2.95 0.120 29644 0 0.120 451.55 3.05 0.123 30691 0 0.123 451.65 3.15 0.125 31742 0 0.125 451.75 3.25 0.128 32795 0 0.128 451.85 3.35 0.131 33852 0 0.131 451.95 3.45 0.133 34911 0 0.133 452.05 3.55 0.136 35973 0 0.136 452.15 3.65 0.138 37039 0 0.138 452.25 3.75 0.141 38107 0 0.141 452.35 3.85 0.143 39178 0 0.143 452.45 3.95 0.146 40253 0 0.146 452.55 4.05 0.148 41330 0 0.148 452.65 4.15 0.150 42410 0 0.150 452.75 4.25 0.153 43493 0 0.153 452.85 4.35 0.155 44580 0 0.155 452.95 4.45 0.157 45669 0 0.157 453.00 4.50 0.158 46215 0 0.158 453.10 4.60 0.622 47308 0 0.622 453.20 4.70 1.47 48405 0 1.47 453.30 4.80 2.56 49505 0 2.56 453.40 4.90 3.86 50607 0 3.86 453.50 5.00 5.33 51713 0 5.33 453.60 5.10 6.76 52822 0 6.76 453.70 5.20 7.29 53933 0 7.29 453.80 5.30 7.79 55048 0 7.79 453.90 5.40 8.25 56166 0 8.25 454.00 5.50 8.69 57286 0 8.69 454.10 5.60 9.11 58410 0 9.11 454.20 5.70 9.50 59536 0 9.50 454.30 5.80 9.89 60666 0 9.89 454.40 5.90 10.25 61798 0 10.25 454.50 6.00 10.61 62934 0 10.61 454.60 6.10 10.95 64072 0 10.95 454.70 6.20 11.29 65214 0 11.29 454.80 6.30 11.61 66358 0 11.61 454.90 6.40 11.92 67506 0 11.92 455.00 6.50 12.23 68656 0 12.23 J:IOataIRENI10&-049\OeslgnlStormITIRlStorm Cales.xls: Stage-Stor (2) Res-pond.rs1 one outlet Reservoir Routing File stage (Ft) 0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.16 0.26 0.36 0.46 0.56 0.66 0.76 0.86 0.96 1.00 1.02 1.03 1.05 1.07 1.08 1.10 1.12 1.13 1.15 1.25 1.35 1.45 1.55 1.65 1.75 1.85 1.95 2.05 2.15 2.25 2.35 2.45 2.55 2.65 2.75 2.85 2.95 3.05 3.15 3.25 3.35 3.45 3.55 3.65 3.75 3.85 3.95 4.05 4.15 4.25 4.35 4.45 Discharge (CFS) 0.000 0.002 0.002 0.002 0.003 0.003 0.003 0.005 0.007 0.008 0.009 0.010 0.011 0.012 0.012 0.013 0.013 0.014 0.016 0.018 0.022 0.027 0.033 0.038 0.040 0.041 0.050 0.057 0.063 0.068 0.073 0.078 0.082 0.086 0.090 0.094 0.098 0.101 0.104 0.108 0.111 0.114 0.117 0.120 0.123 0.125 0.128 0.131 0.133 0.136 0.138 0.141 0.143 0.146 0.148 0.150 0.153 0.155 0.157 page I, storage (Cu-Ft) O. 184. 280. 376. 472. 568. 664. 1625. 2589. 3556. 4526. 5499. 6475. 7454. 8436. 942l. 9816. 10014. 10113. 10310. 10508. 10607. 10805. 11004. 11103. 1130l. 12295. 1329l. 14291. 15294. 16299. 17308. 18319. 19334. 20352. 21372. 22396. 23422. 24452. 25484. 26520. 27558. 28600. 29644. 3069l. 31742. 32795. 33852. 34911. 35973, 37039. 38107. 39178. 40253. 41330. 42410. 43493. 44580. 45669. Monday. November 06, K C RTS (:::Jt: .(cv po" J ( D",,---o-L<-.\-~ ~ perm-Area (Sq-Ft) O. o. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. 2006, 5:23:30 PM 4.50 4.60 4.70 4.80 4.90 5.00 5.10 5.20 5.30 5.40 5.50 5.60 5.70 5.80 5.90 6.00 6.10 6.20 6.30 6.40 6.50 0.158 0.622 1.470 2.560 3.860 5.330 6.760 7.290 7.790 8.250 8.690 9.110 9.500 9.890 10.250 10.610 10.950 11.290 11.610 11.920 12.230 Res-pond. rs1 46215. 47308. 48405. 49505. 50607. 51713 . 52822. 53933. 55048. 56166. 57286. 58410. 59536. 60666. 61798. 62934. 64072 . 65214. 66358. 67506. 68656. 448.50 Ft : Base Reservoir Elevation 0.0 Minutes/Inch: Average perm-Rate o. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. O. page 2, MOnday. November 06, 2006, 5:23:30 PM Flow Frequency Analysis Time Series File:rdout.tsf Project Locatlon:Sea-Tac ---Annual Peak Flow Rates--- Flow Rate Rank Time of Peak (CFS) 0.070 2 2/09/01 20:00 0.015 7 1107/02 4:00 0.059 3 3/06/03 22:00 0.01l 8 8/26/04 7:00 0.017 6 1108/05 5:00 0.037 5 1119/06 0:00 0.056 4 11124/06 8:00 0.074 1 1109/08 14:00 Computed Peaks rdout.pks -----Flow Frequency Analysls------- --Peaks --Rank Return Prob CCFS) Cft) Period 0.074 1.68 1 100.00 0.990 0.070 1.59 2 25.00 0.960 0.059 1.39 3 10.00 0.900 0.056 1.34 4 5.00 0.800 0.037 1.12 5 3.00 0.667 0.017 1.04 6 2.00 0.500 0.015 1.02 7 1.30 0.231 0.011 0.66 8 1.10 0.091 0.073 1.65 50.00 0.980 Page I, Monday, November 06, 2006, 5:30:55 PM Flow Frequency Analysis Time Series Fl1e:dsout.tsf Project Location:Sea-Tac ---Annual Peak Flow Rates--- Flow Rate Rank Time of Peak (CFS) 0.073 2 2/09/01 20:00 0.015 7 1/07102 3:00 0.061 3 3/06/03 21:00 0.012 8 8/26/04 5:00 0.017 6 1108/05 2:00 0.039 5 1118/06 23:00 0.059 4 11/24/06 7:00 0.077 1 1109/08 11: 00 Computed Peaks dsout.pks -----Flow Frequency Analysls------- -Peaks Rank Return Prob (CFS) Period 0.077 1 100.00 0.990 0.073 2 25.00 0.960 0.061 3 10.00 0.900 0.059 4 5.00 0.800 0.039 5 3.00 0.667 0.017 6 2.00 0.500 0.015 7 1.30 0.231 0.012 8 1.10 0.091 0.076 50.00 0.980 Page I, Monday, November 06, 2006, 5:30:35 PM 0+0 J> < <; . o ~ .. " t-{··· f"{ ...... o o ..- ~ • o ..- N • 0 ..- M • 0 ..- o ..- on r------+------~------+_----~------~. o O~'O 80'0 90'0 '0 lO'O 00' ..- Q) 0 II: Q) "tJ Q) Q) ~ .2:-= :a as .c e Q. I I I I I I I I I I I I I I I I I I I EMERGENCY OVERFLOW SPILLWAY City of Renton Hazen Reservoir Pond Spillway REN 105.049 Q = (213) • C • b' (2g)0.5 • H'5 C = Weir Coeeficient (0.5 to 0.57 for braod-crested weirs) b = Bottom width of weir g = Acceleration of gravity (32.2 fIIs2) H = Depth of water at weir crest c= b= H= 0= 0.50 (dimensionless) 13.3 ft 0.4 ft 9.00 cfs' • This flow was selected based on the maximum reservoir overflow. 453.00 Design Water Surface Elevation (It) 453.30 Overflow Water Surface Elevation 9 0'00 (cfs) 0.4 H (ftl 10.12 = L calculated 10.1 Weir Length, L (ft) 453.70 Max. Water Height during overflow (ft) 454.00 Top Berm Elevation (ft) J:\OalaIREN\105·04910esignlSlormITlRIStorm Calts.x1s : Spillway Appendix C , " j i ~ .- 'j ; :; ;;i ii 0 • \ , , , i : , l ii ~O i. ~I II r ,I J Ii ., I! II 'I I. LJiii IT • 0; I i! i i 1 " 1 I • II g.l' ! " , i 1 ~ J: j:; I! ~g • . , I [H ~ ! -a~ ., " _i. .: , I g -$ .. -t: ',~ @. 'I I :i , ' il ii": I ~ --... -, .-------=~-,_.__.·;r I Appendix D •• •• • • - .. . ~- .. J ' , j , .. • .' 11- I • ___ 1 • t . • J ~ ~' • ~ , • ...--::---, >r - ~ Q '~AV • * • • • ( . . - , • ., -.. -' .' ... • • • .-0 .~ T ---• . I ..' . '-~ , . Jit • , I ,,' __ ,f" -. t -1 , o;r • --' ~. '.-f" I I ~ _ \ I (_.L .' • __ "._ .u • ,\J.~ I " ...... • ·-i.t.;; ... · . . r. ~ • • • ,'" ~ '.;. . ,,~.., ,.:1 ~ ... ;~"'j •. ,' -• -r " oj . , • I I ( • • • , -, .. • ~t ••• • ••• • • . - • • .' u"J~ /~ ... - • ..., ___ .... 11.. • -'"' .. .. ......_ ..... ~_ ..... -a. .. -w , ----- L ~\ , . .~ ... o~ / <.) .., .~ / '-' ~\ ~ -~r ---J ., r O ' , I ' ~ .-o ' L\ ,/ v i f I r '" / / I No. 1-Site Looking Northwest No . 3- No. 4 - No . 5- No. 6- No. 7- No. 8- I I I I I I I I I I I I I I I I I I I N o. 11- N o. 12- I N o . 15- N o. 16- No. 17- No. 18- Appendix E Flow Frequency Analysis Time Series File:convey.tsf Project Location:Sea-Tac - --Annual Flow Rate (CFS) 0.534 0.359 0.972 0.374 0.542 0.555 0.577 1.15 Peak Flow Rates--- Rank Time of Peak 6 8/27/01 18:00 8 1/06/02 1:00 2 12/08/02 17:15 7 8/25104 23:45 5 10/28/04 16:00 4 10/22/05 10:00 3 10/25/06 22:45 1 1/09108 6:30 Computed Peaks convey.pks -----Flow Frequency Analysis------- -Peaks Rank Return Prob (CFS) Period 1.15 1 100.00 0.972 2 25.00 0.577 3 10.00 0.555 4 5.00 0.542 5 3.00 0.534 6 2.00 0.374 7 1.30 0.359 8 1.10 1.09 50.00 0.990 0.960 0.900 0.800 0.667 0.500 0.231 0.091 0.980 Page I, Wednesday, November 08, 2006, 2:06:51 PM Project Description Project File Worksheet Flow Element Method Solve For Input Data Worksheet Worksheet for Triangular Channel j:ldatalrenI105-049Idesignlstormltirlapp e -conveyancelflow_mas.fm2 Renton Hazen Reservoir Triangular Channel Manning's Formula Channel Depth Mannings Coefficient 0.030 Channel Slope Left S ide Slope Right Side Slope Discharae ResuHs Depth Flow Area Wetted Perimeter Top Width Critical Depth Critical Slope Velocity Velocity Head Specific Energy Froude Number Flow is subcritical. 11108/06 12:29:30 PM 0.005000 filII 3.000000 H : V 3.000000 H : V 0.97 cIs 0.49 ft 0.73 ft' 3.12 ft 2.96 II 0.37 II 0.024798 ftIft 1.33 fils 0.03 ft 0.52 ft 0.47 Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 AawMaster vS.15 Page 1 of 1 Project Description Project File Worksheet Flow Element Method Solve For Input Data Worksheet Worksheet for Triangular Channel j:ldatalrenI105-049ldesignlstormltirlapp e -conveyancelflow_mas.fm2 Renton Hazen Reservoir Triangular Channel Manning's Formula Discharge Mannings Coefficient Channel Slope Depth 0.030 0.005000 ftlft 1.00 ft Left Side Slope Right Side Slope Results Discharge Flow Area Wetted Perimeter Top Width Critical Depth Critical Slope Velocity Velocity Head Specific Energy Froude Number Flow is subcritical. 11108/06 12:31:06 PM 3.000000 H : V 3.000000 H : V 6.39 cfs 3.00 ft2 6.32 ft 6.00 ft 0.78 ft 0.019287ftlft 2.13 ftls 0.07 ft 1.07 ft 0.53 Haestad Methods, Inc. 37 Brookside Road Walerbury, CT 06708 (203) 755-1666 FlowMaster vS.15 Page 1 of 1 Solve For: Headwater Elevation Culvert Summary Allowable HW Elevation Computed Headwater Elevation Inlet Control HW Elev Outlet Control HW Elev Grades Upstream Invert Length Hydraulic Profile Profile Slope Type 454.90 ft 453.08 ft 453.00 ft 453.08 ft 452.40 ft 32.00 ft 81 Steep Subcritical Culvert Calculator Report Culvert 1 Headwater Depthl Height Discharge T ailwaler Elevation Control Type Downstream Invert Constructed Slope Depth, Downstream Normal Depth Critical Depth 0.68 0.97 cIs 453.00 ft Outlet Control 452.00 ft 0.012500 ftIft 1.00 ft 0.34 ft 0.41 ft Flow Regime Velocity Downstream 1.24 ftis Critical Slope 0.005785 ftIft Section Section Shape Section Material Section Size Number Sections Qultet Control Properties Outlet Control HW Elev Ke Inlet Control Properties Inlet Control HW Elev Circular CPEP 12 inch 1 453.08 ft 0.50 453.00 ft Inlet Type K M C Y End-Section Conforming to fill slope 0.00980 2.00000 0.03980 0.67000 Project Title: Hazen Reservoir j:\. .. \ 1 05~049\design\stolTTl\tjr\appe-c-1 \hazen.cvm 11/08106 11:45:46 AM @HaestadMethods, Inc. Mannings Coefficient Span Rise Upstream Velocity Head Entrance Loss 0.013 1.00 ft 1.00 ft 0.06 ft 0.03 ft Flow Control Unsubmerged Area Full HD8 5 Chart HDS 5 Scale Equation Form RH2 Engineering 37 Brookside Road Waterbury, CT 06708 USA 0.8 1 1 ft· Project Engineer: Brei Beaupain CulvertMaster v1.0 (203) 755-1666 Page 1 of 1 Solve For; Headwater Elevation Culvert Summary Allowable HW Elevation Computed Headwater Elevation Inlet Control HW Elev Outlet Control HW Elev Grades Upstream Invert Length Hydraulic Profile Profile Slope Type 456.00 ft 455.65 ft 455.58 ft 455.65 ft 455.00 ft 61.00 ft S2 Steep Supercritical Culvert Calculator Report Culvert 2 Headwater DepthJ Height Discharge Tailwater Elevation Conlrol Type Downstream Invert Constructed Slope Depth, Downstream Normal Depth Critical Depth 0.65 0.97 cis 453.00 ft Oullet Control 454.00 ft 0.016393 fVfI 0.31 ft 0.31 ft 0.41 ft Flow Regime Velocity Downstream 4.61 Ills Critical Slope 0.005785 ft/ft Section Section Shape Section Material Section Size Number Sections Oullet Control Properties Dudel Control HW Elev Ke Inlet Control Properties Circular CPEP 12 inch 1 455.65 ft 0.50 Inlet Control HW Elev 455.58 ft Inlet Type End-Section Conforming to fill slope K 0.00980 M C Y Project Title: Hazen Reservoir 2.00000 0.03980 0.67000 j:L.\ 1 0S-049\design\storm\tinappe-c-1 \hazen.cvm 11/08J06 11:47:36 AM © Haeslad Methods, Inc. Mannings Coefficient Span Rise Upstream Velocity Head Entrance Loss Flow Control Area Full HDS 5 Chart HDS 5 Scale Equation Form RH2 Engineering 0.013 1.00 ft 1.00 ft 0.16 ft 0.08 ft Unsubmerged 0.8 ft2 Project Engineer: Brei Beaupain CulvertMaster v1.0 37 Brookside Road Waterbury, CT 06708 USA (203) 755-1666 Page 1 of 1 Appendix F OPERATIONS AND MAINTENANCE MANUAL FOR HAZEN RESERVOIR STORMW ATER FACILITIES DETENTION PONDS Maintenance Defect or Problem Conditions When Maintenance Is Needed Results Expected When Component Maintenance Is Performed General Trash & DebriS Any trash and debris which exceed 1 cubic foot Trash and debris cleared from site. per 1,000 square feet (this is about equal to the amount of trash it would take to fill up one standard size office garbage can). In general, there should be no visual evidence of dumping. Poisonous Vegetation ArTy poisonous or nuisance vegetation which may No danger of poisonous vegetation or Noxious Weeds constitute a hazard to County personnel or the where County personnel or the public. public might normally be. Coordination with SeaWe-King County Health Department Contaminants and Oil, gasoline, or other contaminants of one gallon No contaminants present other than PolluUon or more, or any amount found that could: 1) a surface film. (Coordination with cause damage to plant, animal, or marine life; 2) SeaWe/King County Health constitute a fire hazard; or 3) be flushed Department) downstream during rain storms. Unmowed If facility is located in private residential area, When mowing is needed, GrasslGround Cover mowing is needed when grass exceeds 18 grass/ground cover should be Inches in height. In other areas, the general mowed to 2 inches in height. Mowing policy is to make the pond site match adjacent of selected higher use areas rather ground cover and terrain as long as there is no than the entire slope may be Interference with the function of the facility. acceptable for some situations. Rodent Holes Any evidence of rodent holes if facility is acting Rodents destroyed and dam or berm as a dam or berm, or any evidence of water repaired. (Coordination with piping through dam or berm via rodent holes or Seattle/King County Health other causes. Department) Insects VVhen insects such as wasps and hornets Insects destroyed or removed from interfere with maintenance activities. Mosquito site. Mosquito control: Swallow complaints accompanied by presence of high nesting boxes or approved larvicide mosqUito larvae concentrations (aquatic phase). applied. Tree Growth Tree growth threatens integrity of berms acting Trees do not hinder maintenance as dams, does not allow maintenance access, or activities. Harvested trees should be interferes with maintenance activity (i.e., slope recycled into mulch or other mowing, silt removal, vactoring, or equipment beneficial uses (e.g., alders for movements). If trees are a threat to berm firewood). integrity or not interfering with access, leave trees alone. DETENTION PONDS (continued) Maintenance Defect or Problem Conditions When Maintenance Is Needed Results Expected When Component Maintenance Is Performed Side Slopes of Pond Erosion Slopes should be stabilized by using appropriate erosion control Eroded damage over 2 Inches deep where cause measure(s); e.g., rock reinforcement, of damage is still present Of where there is planting of grass, compaction. potential for continued erosion. Any erosion observed on a compacted berm embankment. If erosion is occurring on compacted berms a licensed civil engineer should be consulted to resolve source of erosion. Storage Area Sediment Accumulated sediment that exceeds 10% of the Sediment cleaned out to designed designed pond depth, pond shape and depth; pond reseeded if necessary to control erosion. Liner Damage (If Liner is visible and has more than three Xlnch Liner repaired or replaced. Applicable) holes in it. Pond Benms (Dikes) Seltlement Any part of berm that has settled 4 inches lower Dike should be built back to the than the design elevation. Settling can be an design elevation. indication of more severe problems with the berm or outlet works. A licensed civil engineer should be consulted to determine the source of the settlement. Emergency Tree Growth Tree growth on emergency spillways create Trees should be removed. If root Overflow/Spillway blockage problems and may cause failure of the system is small (base less than 4 and Benns over 4 benn due to uncontrolled overtopping. Tree inches) the root system may be left feet In height. growth on berms over 4 feet in height may lead to in place. otherwise the roots should piping through the benm which could lead to be removed and the berm restored. failure of the berm. A licensed civil engineer should be consulted for proper berm/spillway restoration. Emergency Rack Missing Only one layer of rock exists above native soil in Replace rocks to design standards. Overflow/Spillway area five square feet or larger, or any exposure of native soil at the tap of out flow path of spillway. Rip-rap on inside slopes need not be replaced. CONTROL STRUCTURE/FLOW RESTRICTOR Maintenance Defect or Problem Condition When Maintenance Is Needed Results Expected When Component Maintenance is Performed General Trash and Debris Distance between debris bulld-up and bottom of All trash and debris removed. (Includes Sediment) orifice plate is less than 1,5 feet. Structural Damage Structure is not securely attached to manhole Structure securely attached to wall wall and outlet pipe structure should support at and outlet pipe. least 1,000 Ibs of up or down pressure, Structure is not in upright position (allow up to Structure in correct position. 10% from plumb). Connections to outlet pipe are not watertight and Connections to outlet pipe are water show signs of rust. tight; structure repaired or replaced and works as deSigned. Any holes-other than designed holes-in the Structure has no holes other than structure. designed holes. Cleanout Gate Damaged or Missing Cleanout gate is not watertight or Is missing. Gate is watertight and works as designed. Gate cannot be moved up and down by one Gate moves up and down easily and maintenance person. is watertight. Chain/rod leading to gate is missing or damaged. Chain Is In place and works as designed. Gate is rusted over 50% of its surface area. Gate is repaired or replaced to meet design standards. Orifice Plate Damaged or Missing Control device is not working property due to Plate is in place and works as missing, out of place, or bent orifice plate. designed. Obstructions Any traSh, debris, sediment, or vegetation Plate is free of all obstructions and blocking the plate. works as designed. Overflow Pipe Obstructions Any trash or debris blocking (or having the Pipe is free of all obstructions and potential of blocking) the overflow pipe. works as designed. Manhole Cover Not in Place Cover is missing or only partially in place. Any Manhole is closed. open manhole requires maintenance. Locking Mechanism Mechanism cannot be opened by one Mechanism opens with proper tools. Not Working maintenance person with proper tools. Bolts into frame have less than Y~.i~ch of thread (may not aDDlv to self-Iockina lids. Cover Difficult to One maintenance person cannot remove lid after Cover can be removed and Remove applying 80lbs of lift. I ntent Is to keep cover from reinstalled by one maintenance sealfno' off access to maintenance. I oerson. Ladder Rungs Unsafe King County Safety Office and/or maintenance Ladder meets design standards. person judges that ladder is unsafe due to Allows maintenance person safe mlsslno' runas, misalianment, rust. or cracks. access. CATCH BASINS Maintenance Defect or Problem Conditions When Maintenance Is Neaded Results Expected When Component Maintenance Is performed General Trash & Debrts Trash or debris of more than ~ cubic foot which No Trash or debris located (Includes Sediment) is located immediately in front of the catch basin immediately in front of catch basin opening or is blocking capacity of the basin by opening. more than 10%. Trash or debris (in the basin) that exceeds 1h the No trash or debris in the catch depth from the bottom of basin to Invert the basin. lowest pipe into or out of the basin. Trash or debris in any inlet or outlet pipe blocking Inlet and outlet pipes free of trash or more than 1/3 of its height. debris. Dead animals or vegetation that could generate No dead animals or vegetation odors that could cause complaints or dangerous present within the catch basin. gases (e.g., methane). Deposits of garbage exceeding 1 cubic foot in No condition present which would volume. attract or support the breeding of Insects or rodents. Structure Damage to Comer of frame extends more than % Inch past Frame is even with curb. Frame and/or Top curb face into the street (If applicable). Slab Top slab has holes larger than 2 square inches Top slab is free of holes and cracks. or cracks wider than X inch (intent is to make sure all material is running into basin). Frame not sitting flush on top slab, i.e., Frame is sitting flush on top slab. separation of more than % inch of the frame from the top slab. Cracks in Basin Cracks wider than 1h inch and longer than 3 feet, Basin replaced or repaired to design Wails/Bottom any evidence of soil particles entering catch standards. basin through cracks, or maintenance person judges that structure is unsound. Cracks wider than 1h inch and longer than 1 foot No cracks more than 1/4 inch wide at at the joint of any inleUoutlet pipe or any evidence the Joint of Inlet/outlet pipe. of soil particles entering catch basin through cracks. Settlement/ Basin has settled more than 1 inch or has rotated Basin replaced or repaired to design Misalignment more than 2 inches out of alignment. standards. Fire Hazard Presence of chemicals such as natural gas, oil No flammable chemicals present. and gasoline. Vegetation Vegetation growing across and blocking more No vegetation blocking opening to than 10% of the basin opening. basin. Vegetation growing in inleUoutlet pipe joints that No vegetation or root growth is more than 6 inches tall and less than 6 inches present. apart. Pollution Nonflammable chemicals of more than % cubic No pollution present other than foot per three feet of basin length. surface film. Catch Basin Cover Cover Not in Place Cover is missing or only partially in place. Any Catch basin cover is closed open catch basin requires maintenance. Locking Mechanism Mechanism cannot be opened by on Mechanism opens with proper tools. Not Working maintenance person with proper tools. Bolts into frame have less than % inch of thread. Cover Difficult to One maintenance person cannot remove lid after Cover can be removed by one Remove applying 80 Ibs. of lift; intent is keep cover from maintenance person. sealing off access to maintenance. CATCH BASINS (continued) Malmenance Defect or Problem Conditions When Maintenance Is Needed Results Expected When Component Maintenance Is perfonnad Ladder Ladder Rungs Unsafe Ladder is unsafe due to missing rungs, Ladder meets design standards and misalignment, rust, cracks, or sharp edges. allows maintenance person safe access. Melal Grates (If Unsafe Grate Grate with opening wider than 7/8 inch. Grate opening meets design Applicable) Opening standards. Trash and Debris Trash and debris that is blocking more than 20% Grate free of trash and debris. of grate surface. Damaged or Missing. Grate missing or broken member(s) of the grate. Grate is in place and meets design standards. DEBRIS BARRIERS (E.G., TRASH RACKS) Maintenance Defect or Problem Condition When Maintenance Is Needed Results Expected When Component Maintenance Is Performed. General Trash and Debris Trash or debris that is plugging more than 20% at the openings in the barrier. Barrier clear to receive capacity flow. Melal Damaged/Missing Bars are bent out of shape more than 3 inches. Bars In place with no bends more Bars. than % Inch. Bars are missing or entire barrier missing. Bars In place according to design. Bars are loose and rust is causing 50% Repair or replace barrier to design deterioration to any part at barrier. standards. ENERGY DISSIPATERS Maintenance Detect or Problem Conditions When Maintenance Is Needed Results Expected When Component Maintenance Is Performed. Extemal: Rock Pad Missing or Moved Only one layer of rock exists above native soil in Replace rocks to design standards. Rock area five square teet or larger, or any exposure of native soil. Dispersion Trench Pipe Plugged wilh Accumulated sediment that exceeds 20% at the Pipe cleanedtnushed so Ihat It Sediment design depth. matches design. Not Discharging VIsual evidence of water discharging at Trench must be redesigned or Water Properly concentrated paints along trench (normal rebuilt to standards. condition is a "sheet floW' otwater along trench). Intent is to prevent erosion damage. Perforations Plugged. Over % of perforations in pipe are plugged with Clean or replace perforated pipe. debris and sediment. Water Flows Out Top Maintenance person observes water flowing out Facility must be rebuilt or redesigned of ~Distributor" Catch during any storm less than the design storm or Its to standards. Basin. causing or appears likely to cause damage. Receiving Area Over-Water in receiving area is causing or has No danger of landslides. Saturated potential of causing landslide problems. Internal: Manhole/Chamber Worn or Damaged Structure dissipating flow deteriorates to "XI or Replace structure to design Post. Baffles, Side of Original size or any concentrated worn spot standards. Chamber exceeding one square foot which would make structure unsound. I I FENCING Maintenance Delect or Problem Conditions When Maintenance is Needed Results Expected When I Component Maintenance 1& Partonned General Missing or Broken Any defect in the fence that permits easy entry to Parts in place to provide adequate Parts a facility. security. I Erosion Erosion more than 4 inches high and 12-18 No opening under \he fence that Inches wide permitting an opening under a fence. exceeds 4 Inches in height. Wire Fences Damaged Parts Post out of plumb more than 6 inches. Post plumb to within 1% inches. I Top rails bent more than 6 inches. Top rail free of bends greater than 1 Inch. Any part of fence (including post, top rails, and Fence Is aligned and meets design fabric) more than 1 foot out of design alignment. standards. I Missing or loose tension wire, Tension wire in place and holding fabric. Missing or loose barbed wire that is sagging Barbed wire in place with less than I more than 214 inches between posts. % inch sag betw'een post Extension arm missing, broken, or bent out of Extension ann in place with no shape more than 1% inches. bends larger than % inch, I Deteriorated Paint or Part or parts that have a rusting or scaling Slru<::turally adequate posts or parts Protective Coating condition that has affected structural adeq:uacy. with a uniform protective coating, Openings in Fabric Openings in fabriC are such that an &-inch No opernngs In fabric. I diameter ban could fit through. I GATES Maintenance Defect or Problem Conditions When Maintenance 18 N"ded Results Expected When Component Maintenance Is I'!Irformed I General Damaged or Missing Missing gate or locking devices. Gates and lOCking devJces in place. Members Broken or missing hinges such that gate cannot Hinges Intact and lubed. Gate is I be easily opened and closeO by a maintenance worKing freely. person. Gate Is out of plumb more than 6 inches and Gate is aligned and vertical. I more than 1 foot out of des!gn alignment Missing stretcher bar, stretcher bands, and ties. Stretcher bar, bands, and ties in place. I Openings in Fabric Openings in fabric are such that an 8-lnch No openings In fabric. diameter ball could fit throullh. I I I I I CONVEYANCE PIPES AND DITCHES Maintenance Defect or Problem Conditions When Maintenance Is Needed Results Expected When Component Maintenance Is Performed Pipes Sediment & Oebrts Accumulated sediment that exceeds 20% of the Pipe cleaned of all sediment and diameter of the pipe. debris. Vegetation Vegetation that reduces free movement atwater All vegetation removed so water through pipes. flows freely through pipes. Damaged Protective coating is damaged; rust Is causing Pipe repaired or replaced. more than 50% deterioration to any part of pipe. Ally dent that decreases the cross section area of Pipe repaired or replaced. pipe by more than 20%. Open Ditches Trash & Debris Trash and debris exceeds 1 cubic foot per 1,000 Trash and debris cleared from square feet of ditch and slopes. ditches. Sediment Accumulated sediment that exceeds 20% of the design depth. Ditch cleaned/flushed of all sediment and debris so that it matches design. Vegetation Vegetation that reduces free movement of water Water flows freely through ditches. through ditches. Eroded damage over 2 inches deep where cause Slopes should be stabilized by using of damage is stili present or where there is appropriate erosion control potential for continued erosion. measure(s); e.g., rock reinforcement, planting of grass, Erosion Damage to Any erosion observed on a compacted berm compaction. Slopes embankment. If erosion is occurring on compacted berms a licensed civil engineer should be consulted to resolve source of erosion. Rock Lining Out of Maintenance person can see native soli beneath Replace rocks to design standards. Place or Missing (If the rock lining. Applicable). GROUNDS (LANDSCAPING) Maintenance Defect or Problem Conditions When Maintenance Is Needed Results Expected When Component Maintenance Is Perfonned General Weeds weeds growing in more than 20% of the Weeds present in less than 5% of (Nonpoisonous, not landscaped area (trees and shrubs only). the landscaped area. noxious) Safety Hazard AIly presence of poison ivy or other poisonous No poisonous vegetation present in vegetation. landscaped area. Trash or Litler Paper, cans, bottles, totaling more than 1 cubic Area clear of litler. foot within a landscaped area (trees and shrubs only) of 1,000 square feet. Trees and Shrubs Damaged Limbs or parts of trees or shrubs that are split or Trees and shrubs with less than 5% broken which affect more than 25% of the total of total foliage with split or broken foliage of the tree or shrub. limbs. Trees or shrubs that have been blown down or Tree or shrub in place free of injury. knocked over. Trees or shrubs which are not adequately Tree or shrub in place and supported or are leaning over, causing exposure adequately supported; remove any of the roots. dead or diseased trees. ACCESS ROADS Maintenance Defect or Problem Condition When Maintenance Is Needed Results Expected When Component Maintenance Is Perfonned General Trash and Debris Trash and debris exceeds 1 cubic foot per 1,000 RoadWay free of debris which could square feet (i.e., trash and debris would fill up damage tires. one standards size garbage can). Blocked Roadway Debris which could damage vehicle tires (glass or Roadway free of debris which could metal). damage tires. Any obstruction which reduces clearance above Roadway overhead clear to 14 feet road surface to less than 14 feet. high. Any obstruction restricting the access to a 10-to Obstruction removed to allow at 12-100t width for a distance of more than 12 feet least a 12-foot access. or any point restricting access to less than a 10- foot width. Road Surface Settlement, Potholes, \JVhen any surface defect exceeds 6 inches In Road surface uniformly smooth with Mush Spots, Ruts depth and 6 square feet in area. In general. any no evidence of settlement, potholes, surface defect which hinders or prevents mush spots, or ruts. maintenance access. Vegetation In Road Weeds growing in the road surface that are more Road surface free of weeds taller Surface than 6 inches tall and less than 6 Inches tall and than 2 inches. less than 6 inches apart within a 400~square foot area. ModularGrtd Build-up of sediment mildly contaminated with Removal of sediment and disposal in Pavement petroleum hydrocarbons. keeping with Heatth Department recommendations for mildly contaminated soils or catch basin sediments. Shoulders and Erosion Damage Erasion within 1 foot of the roadway more than 8 Shoulder free of erosion and Ditches inches wide and 6 inches deep. matching the surrounding road. Weeds and Brush Weeds and brush exceed 18 Inches In height or Weeds and brush cut to 2 inches in hinder maintenance access. height or cleared in such a way as to allow maintenance access.