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Home My WebLink AboutMisc~-, ' , l i if , I ;:1 • ..• , . t \ •. • STORM DRAINAGE REPORT (Including Downstream Analysis) Lakeside Fairwood Plat Location: 186211161b Ave SE Renton, WA 98055 a.k.a. K.C. PARCEL 3223059113 ") April 26, 2013 Revised August 30,2013 By Hagenson Consultants, LLC Seattle, Washington 98136 HC Job No. 201210 Renton File No. LUA09-079 TABLE OF CONTENTS A. Core and Special Requirements Analysis P j C,, B. Technical Information Report I. Project Overview P 0 l) II. Preliminary Conditions Summary r7 ~ q III. Off-site Analysis (Appendix) P f1 I~ IV. Proposed Drainage Improvements f 'j /) V. Conveyance Systems Analysis and Design f q f-1; VI. Basin and Community Planning Areas P0 4-(( VII. Other Permits ·y Cj It-I\ VIII. Erosion/Sedimentation Control Design P 9 ~~ IX. Bond Quantities Work Sheet, Retention/Detention Facility, P~ S'b Summary Sheet and Sketch, and Declaration of Covenant, Declaration of Covenant Prohibiting Leachable Metals X. Maintenance and Operation Manual Appendix -Post Office Mailbox Approval -Geotechnical Study -Level One Downstream Analysis KING COUNTY. WASHINGTON. SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 1 PROJECT OWNER AND PROJECT ENGINEER ATIN. YlflllJlJ; itii!i Project Owner LAILE51Di: 12£AL.8TA1l: H.JrJE.rrl1E.l!f, Phone __ ~_~_o_~_-_2_q_,_o_-1_1:_7_1 ____ _ Add 35-;,c-, .. .S,i%ol• ',, ress ------------ SGA1liL Wr.. q bl U Project Engineer i-iAL kAl:.Bi ~ow Company i-f~/,,l:lJSD/11 l'OliS!JLTAIJri LlL Phone L DL>-<Hll-t.i lo~, Part 3 TYPE OF PERMIT APPLICATION ~ Landuse Services Subdivlson I Short Subd. I UPD D Building Services M/F / Commerical I SFR D Cleartng and Grading D Right-of-Way Use D Other Parts PLAN AND REPORT INFORMATION Technical Information Report Type of Drainage Review UiiiCli Targeted (circle): Large Site Date (include revision LJ-1.J,-!\ dates): Date of Final: Part 6 ADJUSTMENT APPROVALS I Part 2 PROJECT LOCATION AND DESCRIPTION Project Name LAl(E S !De f P,1 r,Wbo[) p, '" f{2Ll1l>.J ' u A N, n 7n BBES-Permit # _L_r-._c_LM_· w_·_, ___ _ Location Township Range Section 5E I/ 4 !:>-L Site Address I Br,.,?.• 11 (., "E:-AVf:. ::,c: 12. !:\ff ()1•.i Ml"· Part 4 OTHER REVIEWS AND PERMITS D Shoreline Management D DFWHPA 0 COE404 D DOE Dam Safety D FEMA Floodplain D COE Wetlands D Structural RockeryNaultl __ D ESA Section 7 D 0t11er __ _ Site Improvement Plan (Engr. Plans] Type (circle one): ~/ Modified I all Site Date (include revision 3~! -f) dates): Date of Final: Type ( circle one): Standard I Complex I Preapplication / Experimental / Blanket Description: (include conditions in TIR Section 2) Date of Annroval: 2005 Surface Water Design Manual 1/1/05 K.JNG COUNTY. WASHINGTON. SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 7 MONITORING REQUIREMENTS Monitoring Required: Yes//§) Describe: Start Date: Completion Date: Part 8 SITE COMMUNITY AND DRAINAGE BASIN Community Plan : fl.eilfoN C'olV\t liL.AlJ Special District Overlays: ______________________ _ Drainage Basin: P "-1.fftta Cfl.8;:iL. Stonnwater Requirements: L£ur;L1[ F:oaecWl t-LDro 9>WP( -0A£il Mlltfi QQ/1! m. Part 9 ONSITE AND ADJACENT SENSITNE AREAS 0 River/Stream --------- 0 Lake 0 Wetlands LJrr :nr -Er.E:11 or~ r'lu... 0 Closed Depression --------0 Floodplain _________ _ 0 Other ___________ _ Part 10 SOILS {i:3 Steep Slope Exefl\PT· 12Ebilr. tF-2 .s : I 0 Erosion Hazard --------0 Landslide Hazard ______ _ 0 Coal Mine Hazard------- 0 Seismic Hazard -------- 0 Habitat Protection -------0 __________ _ Soil Type Slopes Erosion Potential f:., § ~ -k-l);!\.u,obO bfU,~,~, 1,;_,_, 5-4D<J. mooERMf 0 High Groundwater Table (within 5 feet) 0 Sole Source Aquifer 0 Other 0 Seeps/Springs 0 Additional Sheets Attached 2005 Surface Water Design Manual 2 J/1/05 ·--· KING COUNTY, WASHINGTON, SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 11 DRAINAGE DESIGN LIMITATIONS REFERENCE LIMITATION/ SITE CONSTRAINT C2J Core 2 -Offsite Anal:i:sis N.OtJE (3 Sensitive/Critical Areas NDNE OsEPA D Other D D Additional Sheets Attached Part 12 TIR SUMMARY SHEET forovide one TIR Summary Sheet =r Threshold Discharge Area) Threshold Discharge Area: ( name or description) P/Lo:5Eu SffE Core Requirements (all 8 apply) Discharae at Natural Location Number of Natural DISchame Locations: I Offsite Analysis Level: IJ,)/2/3 dated: 1£VL >-OQ Flow Control Level: 1 I (VI 3 or Exemption Number /incl. facffitv summaru sheet\ Small Site BMPs Conveyance System Spill containment located at r blrirI.o:... k~Wm .: Erosion and Sediment Control ESC Site Supervisor. 1-1 /..L fi L.Cf lt SDN Contact Phone: ~· f>i.,.. o· ':.1i-· ~,:,[ IJ" r After Hours Phone: 'ZD~-Cr",'i, lr,11,t Maintenance and Operation Responsibffity: Private /f Public, If Private, Maintenance Loo Reouired: Yes /No Financial Guarantees and Provided: es / No Liabilitv Water Quality Type: (Basic)/ Sens. Lake / Enhanced Basicm / Bog (include facility summary sheet) or Exemption-No. Landsca"" Manaaement Plan: Yes I /No) Sn<>cial RAnuirements las annlicablel Area Specific Drainage Type: CDA I SDO I MOP / BP / LMP / Shared Fae. / None R..,-,uirements Name: i=loodplain/Floodway Delineation Type: Major / Minor I Exemption / None 100-year Base Flood Elevation (or range): Datum: Flood Protection Facilities Describe: Source Control Describe landuse: ( commJindustrial landuse) Describe any structural controls: 2005 Surface Water Design Manual 3 1/1/05 KJNG COUNTY, WASHINGTON. SURFACE WATER DESIGN MANUAL TECHNICAL INFORMATION REPORT (TIR) WORKSHEET - Oil Control High-use Site: Yes/~ Treatment BMP: Maintenance Agreement: Yes / ~ with whom? Other Drainage Structures Describe: wrr ·LJE1E1.tf1D/.../ ~DIJO Part 13 EROSION AND SEDIMENT CONTROL REQUIREMENTS MINIMUM ESC REQUIREMENTS MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION AFTER CONSTRUCTION 0 Cleartng Limits Ui:I Stabilize Exposed Surfaces ~ Cover Measures t8I Remove and Restore Temporary ESC Facilities !Sil Pertmeter Protection 121 Clean and Remove All Silt and Debrts Ensure tlil Traffic Area Stabilization Operation of Permanent Facilities 0 Sediment Retention 0 Flag Limits of SAO and open space 0 Surface Water Control preservation areas D Other 0 Dust Control CZI Construction S=uence Part 14 STORMWATER FACILITY DESCRIPTIONS lNote: Include Facililv Summarv and Sketch) Flow Control Tv ...... lnescrlolion Water Qualifv TvnAlnescrtolion Cii3 Detention PDIJD 0 Biofiltralion 0 Infiltration (3 Wetpool C:DMbllJEO 0 Regional Facility D Media Filtration 0 Shared Facility 0 Oil Control 0 Small Site BMPs 0 Spill Control 0 Other Q Small Site BMPs 0 Other 2005 Sutface Water Design Manual 4 1/1/05 fl I -- KING COUNTY. WASHINGTON, SURFACE WATER DESIGN MANUAL L TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 15 EASEMENTSffRACTS Part 16 STRUCTURAL ANALYSIS 1:21 Drainage Easement 0 Cast in Place Vault 0 Access Easement 0 Retaining Wall 0 Native Growth Protection Covenant 0 Rockery > 4' High D Tract D Structural on Steep Slope 0 Other 0 Other Part 17 SIGNATURE OF PROFESSIONAL ENGINEER 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 knowledge the information provided here is accurate. fu,,JJ,L, ~~ shLi1.;. Sinned/Dste 2005 Swface Water Design Manual s 1/1/05 A. CORE AND SPECIAL REQUIREMENTS ANALYSIS This section of the TIR is intended to meet agency specific requirements for a report addressing all Core and Special Requirements of the 2005 King County Surface Water Manual and the Renton Surface Water Manual Addendum. Core Requirement I. Discharge at the Natural Location The discharge location from the existing and developed site is identical. Currently, the site slopes northwesterly between 5% and 40%. General drainage patterns run from the site toward the northwest corner of the property. Post development runoff will be conveyed to a wet detention pond, then to a piped conveyance system and rock discharge pad that will release drainage near the northwesterly property corner Core Requirement 2. Offsite Analysis A level one-offsite analysis is required and is provided in the appendix of the Technical Information Report (TIR). Core Requirement 3: Flow Control Per City of Renton Flow Control Applications Map, the site lies in a Conservation (level 2) flow control area. A single cell combined wet/detention pond is proposed to mitigate increased storm water runoff. Storm water modeling is achieved using the 2005 King County Surface Water Manual, under which the project is vested. Section 1.2.3.3 (KCSWM pg 1-44) requires flow control BMP's be applied to individual lots. Per Section 5.2.1.3, and Table 5.2.lA, since the lot is less than 10,000 s.f. then bmp's are required to be applied to 10% of the site/lot. These BMP's will be deferred to the individual building permit stage, at which time limited infiltration, dispersion, rain gardens, permeable pavements or rainwater harvesting may be applied. Normally, Full Dispersion, (see KCSWM Appendix C, page C-24) is required, but since this site is small and will be densely developed, the required native growth flow lengths are not available. Iffull dispersion is not possible, then full infiltration must be used if feasible (see pg. C-38). Feasibility is based on the presence of 4 to 6 feet of cobbles, coarse or medium sands which are not indicated in the project geotech report. The Geotechnical Engineering Study by Geotech Consultants, page 2, dated 6/19/2009 ( see appendix) indicates up to 7 feet of silty sand fill overlaying glacial till. Limited infiltration (per KCSWM Appendix C.2.3 is also not feasible given the character of the soils. The project geotech report indicates the soils conditions up to 7 feet of silty sand fill overlaying glacial till with perched groundwater conditions at 4 to 7 feet depth. Although KCSWM generally allows infiltration in fill if it was placed in accordance with geotechnical recommendations and percs greater than 8 inches per hour, this fill was placed long ago under unknown conditions. Therefore, site and/or roof downspout limited infiltration is not suitable for the site. If full roof dispersion nor full infiltration is feasible, then mitigation BMPs must be applied. (See pg. 5-6 and C-14, including a selection oflimited infiltration (pg C-23), basic dispersion (pg. C- 49-51 ), rain garden, pervious pavement, rainwater harvesting or reduced site impervious coverage covenants and native growth credits. (pg 5-6 and C-52 to C-71). Our conclusion for a BMP design strategy is that since full dispersion and full infiltration and limited infiltration are not possible, we propose that these BMP's will be deferred to the individual building permit stage, at which, rain gardens, permeable pavements or rainwater harvesting may be applied. Table 5.2.IA requires BMPs on 10% of the 43,570 s.f. site or 20% of the 29,645 s.f. target impervious area whichever is less. This goal is therefore met at I 0% of the site or 4,357 s.f. Roof drains will be tight-lined to the detention tank. See Section IV of the TIR for details. Core Requirement 4: Conveyance System A conveyance system has been designed to direct runoff to the combined wet/detention pond. A conveyance analysis is included in section V. Core Requirement 5: Erosion and Sedimentation Control Preliminary Erosion Control Systems are recommended in Section IX of the TIR and include a stabilized construction entrance, silt fence, and seeding. A CSWPP is also provided in Section IX. A separate ESP Plan has been prepared for the Final Construction Document Phase. Core requirement 6: Maintenance and Operations A maintenance and operations manual sections has been included in Section X of the TIR. Core Requirement 7: Financial Guarantees and Liability The proposed project will include improvements to SE 186th Pl and I 16th Ave SE. Therefore, per paragraph I ofKCSWM 1.2.7, financial guarantees are required and provided herewith. See Section IX. Core Requirement 8: Water Quality The Renton Surface Water Manual (Pgl-63) requires that runoff from multifamily projects must meet the enhanced basic water quality menu unless otherwise exempt. Since this is a residential project, and the project lies within the basic water quality area, basic water quality will be provided by the wet/detention pond. Water quality wetpond calculations are included in Section IV. Special Requirement #1: Other adopted area-specific requirements. The site is located in the Panther Creek sub-basin of the Black River Basin. 7 Special Requirement #2: Floodplain/Floodway delineation The project does not contain nor is adjacent to a stream, lake, wetland or closed depression. The project is not listed in a floodplain per FEMA mapping. Therefore, this requirement does not apply to the site. Special Requirement #3: Flood Protection Facilities The project contains no streams nor flood protection facilities. Therefore, this requirement does not apply to the site. Special Requirement #4: Source Controls Since the project does not require a commercial building/commercial site development permit, Source Controls are not required. Special Requirement #5: Oil Control Since the project is not a High Use Site, defined as Commercial, industrial and multifamily projects, Source Controls are not required. I. PROJECT OVERVIEW The Proposed Development consists of 8 lot single family residential project located at 18624 -l l 6th Ave SE on approximately 1.0 acres. Existing Zoning is R-8. The proposed residential development requires a new public access road (SE 186th Pl) and Frontage Road Improvements (I I 6'h Ave SE) consisting of new sidewalks, curb and gutter and storm drainage. Site design criteria are based on the 2005 King County Storm Drainage Manual along with the City of Renton Surface Water Manual Addendum as adopted by the City at the time of the pre-application conference. II. PRELIMINARY CONDITIONS SUMMARY The property has an existing single-family residence with landscaped yard, garage and driveway. The house and all site improvements will be demolished. A small category 3 wetland is located in the NW comer of the property and a Critical Areas Exemption has been granted to allow development in this area. Existing grades slope generally towards the center of the property. The Hearing Examiner's October 5, 2009 report, Page 5, item 10, indicates that a manmade made slope in the northwest comer of the site slopes greater than fifteen percent ( approximately 40% ), but the geotenchincal letter dated 9/14/2009 ( see appendix) suggests the slope can be regraded and development permitted. Drainage from the site is sheet flows southeast to northwest and then travels to the west in pipe and ditch conveyance systems to SR 167 Panther Creek drainage system. Site slopes vary between 2 and 40 percent. Site soils are classified in SCS mapping as Alderwood gravelly sandy loam (AgC), 6 to 15% slopes, hydrologic class C, till soils. Alderwood series have slow permeability; runoff potential is slow to medium and a moderate to server erosion hazard. There are no indications of closed depressions on the property. A review of available information indicates there are no floodplains, wetlands, aquifer protection areas, liquefiable soils, erosion hazards, landslide hazards nor coal mine hazards on the site nor in the inunediate area. As indicated above, there is a small steep slope area which can be regarded and developed at 2.5:1. Ot ! ...... -· i A~~ "' .~~-' '~ 1..1 U f li"IP"' bl,lpolj -elpollljt Jn .bq!I bt !cl1 oJdpn qjrflel cz!LjohlDpvOtLlt iblllgpn lbl\lb~f u:lp~t pvslf t l boeljt It vcK dutpl ci bohf l <jll,pvlloPlici' /IL)oh Dpvou:ln bl n lopl,t q,t tf <><l>tjpotJpsxbatxlljf t.-!f yq,t t t Jpsjn 9file-!bt !tp!bddvllxlz-!dpn qrful of tt-liit f ~ tt-lps~hi u ltphi'f Jvtf l pgt~ci ljog,9'1 bti>o/ U j l lepdvn f,ouj t loplljod oef.elg>!livt f lb t lblt.vM zlq,pevaIILJohfDpvolt!tl bnlopllcf hjklfll1J>Sboz!hf of !l>Altqf ~~oej,t rulj~ oli>Alpsdpotf r vf otjbm ebn bhf t !jo<ne. joh-lcvllopll,ja jd ehp-l rpt ll,t,w ovf t lpllrpt llQll>IIII IQ' t vll)ohllJpn !li f !vt f !plln jt vt f !p~li Mjo1J>91 b,jpol..,Olbjof elpol u jt In bq/1Bozlt brfltpg li jl In bq!pllj()g>s, bti><J!po!u jt In bq ljt lq,pi jcjd elf ydf quczlx ~Ill olqf 91 Jt tJpolpgLJoh!DpvOLtl Ebtf ;13Cl!9m124!!!111!!!!Tpvd ;!Ljoh!Dpvou:IJNBQ. !Q,pqf ,u:IJ,11>91 ·bljpo!}i uq;Clk xx /n f upl <>'hpwH J QN BO' •· . -,• -- I o _sD,5 _____ _ + IC) 2008 Kmg Cov11ty iMAP _______ _..,...-"--. _____________ .----------- ~--~ ----·,\ \ I I 1: \I --- v ;) ' ~ -~~ ',, .. / " .. --------·· \ / ·-------0 .--· ---------, 128ft \ I I .. 'I if !I 'I /1 wl "'' W • >' <( :t .... , <e j -. -., ,! J· i i ... 'it.o I u, I The information included on this map has been compled by King County staff from a variety of sources end is subject to change wilhout notice. King County -makes no•repmsentations ·or warranties, express or Implied , as to aca.aracy, completeness, time liness. or rights to'the use of such informatio n. This document is not intended for use as. survey product. King County shall.not.be fiable for any general, special, indirect. incidental, o r consequential i:·~. 'K "1n_g :.r ·ouoty damages including. but not fimited.to. lost revenues or lost profits resulting from the use or misuse of the infonnaUon contained on this map. Any sale of -~ this•map or information on this·map is prohibited exceptby written penmission of King County. Date: 6123/2009 Source: King County iMAP -Property lnfonnation (http://www.metrokc.gov/GIS/iMAP) I 1 ! ' rz Page 1 18624 116th Ave SE, Renton, WA Google Earth: Directions 2/18/2013 III. OFF-SITE ANALYSIS (LEVEL ONE DOWNSTREAM DRAINAGE ANALYSIS) OFFSITE DRAINAGE ANALYSIS) See Appendix. L IC I/] I ' ' ' IV. PROPOSED DRAINAGED IMPROVEMENTS Flow Control Per City of Renton Flow Control Applications Map, the site lies in a Conservation (level 2) flow control area. A single cell wet/detention pond is proposed to mitigate increased storm water runoff. Storm water modeling is achieved using KCRTS methodology in compliance with the 2005 King County Surface Water Manual (KCSWM). Section 1.2.3.3 (KCSWM pg 1-44) requires flow control BMP's be applied to individual lots. Per Section 5.2.1.3, and Table 5.2.lA, since the lot is less than 10,000 s.f. then bmp's are required to be applied to 10% of the site/lot. These BMP's will be deferred to the individual building permit stage, at which time limited infiltration, dispersion, rain gardens, permeable pavements or rainwater harvesting may be applied. Normally, Full Dispersion, (see KCSWM Appendix C, page C-24) is required, but since this site is small and will be densely developed, the required native growth flow lengths are not available. If full dispersion is not possible, then full infiltration must be used if feasible (see pg. C-38). Feasibility is based on the presence of 4 to 6 feet of cobbles, coarse or medium sands which are not indicated in the project geotech report. The Geotechnical Engineering Study by Geotech Consultants, page 2, dated 6/19/2009 (see appendix) indicates up to 7 feet of silty sand fill overlaying glacial till. Limited infiltration (per KCSWM Appendix C.2.3 is also not feasible given the character of the soils. The project geotech report indicates the soils conditions up to 7 feet of silty sand fill overlaying glacial till with perched groundwater conditions at 4 to 7 feet depth. Although KCSWM generally allows infiltration in fill if it was placed in accordance with geotechnical recommendations and percs greater than 8 inches per hour, this fill was placed long ago under unknown conditions. Therefore, site and/or roof downspout limited infiltration is not suitable for the site. If full roof dispersion nor full infiltration is feasible, then mitigation BMPs must be applied. (See pg. 5-6 and C-14, including a selection oflimited infiltration (pg C-23), basic dispersion (pg. C- 49-51 ), rain garden, pervious pavement, rainwater harvesting or reduced site impervious coverage covenants and native growth credits. (pg 5-6 and C-52 to C-71). Our conclusion for a BMP design strategy is that since full dispersion and full infiltration and limited infiltration are not possible, we propose that these BMP' s will be deferred to the individual building permit stage, at which, rain gardens, permeable pavements or rainwater harvesting may be applied. Table 5.2. lA requires BMPs on 10% of the 43,570 s.f. site or 20% of the 29,645 s.f. target impervious area whichever is less. This goal is therefore met at I 0% of the site or 4,357 s.f. This would typically involve applying BMPs on 2 of the individual lots. Roof drains will be tight-lined to the detention tank. See Section IV of the TIR for details. Installation of a rock pad for storm water outflow at the property line is allowed when 100 year peak flows are less than 0.2 cfs (design peak outflow discharge is 0.084 cfs). Water Quality Treatment The Renton Surface Water Manual (Pgl-63) requires that runoff from single family residential projects must meet the basic water quality menu unless otherwise exempt. The single cell wetpond facility is allowed where the wet pond volume is less than 4,000 c.f. (4,179 c.f. design) or where the length to width ratio is greater than 4:1 (5: 1 design). Access to the pond can be truncated 4 feet above the pond bottom where the pond bottom is less than 1500 s.f. ( 489 s.f design). ' . . (, 5.2.! INDIVIDUAL LOTBMP REQUIREMENTS ' - FIGURE 5.2.1.A FLOW CHART FOR DETERMING INDIVIDUAL LOT BMP REQUIREMENTS Is the project on a sttellot (Yes\ lsttfeasibleand smaller than 22,000 square 1"t? '--.../ applicable to implement full Yes No further BMPs Apply one or more of the following to impervious area dispersion for lhe required. Note: .,_10% of sitJJ/lol. for sifsllot sizes <11,000 sf and .,_w,1, of roof area as per MY proposed sllellot for site/lot sizes between 11,000 and 22,000 sf (For Section C2.1? connection of roof projeels localed in crllical aquifer recharge """'8 these ®· downspouts to impal\llous area amounts double): local dminage 1. Umlted lnftlbmion (Seclion C.2.3) lsit-e system must be 2. Basic Dlspereion (Section C2.4) via perforated 3. Rain Garden (Section C.2.5) and applicable pipe connection 4. Penneable Pavement (Section C.2.6) (§> to implement Yes per Section 5. Rain-Harvesting (Section C.2.7) fuU inlilb attou C.2.11. No 6. Vegamwd Roof (Section C.2.8) of the roof 7. Reduced Impervious Service Crvdlt (Section C.2.9) runoff as per ' 6. -Growth Ratantion Cradit (Section C.2. 10) Section C.2.2? I " , um projeCt on a ::oftll'n.N. "--squant feet Yes Is ft feasible and or larger with Impervious surface applicable to implement coven,-of 45% or less? full dlsperelon on au Yes 18,get lmpal'ilfous No futlher BMPs ...,,_asper required. Note: une or mon, 01 the I -I'S must be implemented . Seclion C.2.1? Aro/ proposed connedionofroof No for !hat portion of larget /mpelVlouS surface not eddressed Not ~tolocal wilh luff dispersio,1 or with full -of roof runoff: drainage syslem 1. Fult lnllnration (Section C.2.2 or Section 5-4) ls It feastbte and applicable to must be via 2. l.imlled Infiltration (Section C.2.3) -No implement full lnfillratlon of pelforated pipe a Besic Dispersion (Section C.2.4) Ille roof nBIOlf as per connactton per 4. Rain Ganlen (Section C.2.5} Sec1ion C.2.2 or Section 5.4? Section C.2.11. 5. -le Pawmellt (Seclion C.2.6) Yest 6. Ralnwatar Hm ,esting (Section C.2.7) Yes ~ ' ' 7. Veg-Roof (Section C.2.8) Is there any ramaining bltget 8. Reduced lmpenrious 5enrice Credit (S-C.2.9) impervious Slllfat:e not No 9. Native Growth Ratentior, Credit,-. C.2.10l addressed wilh ruu dispersion or -I with full lnfiltration of roof runall'? The project must be a sltBllot 22,000 square -Is It feasible and or larger wllh ..._,,;ow, surface applicable to implement co-age of more than 45%? fllll cllsporsion on au ""9at lmpe,vious ~-- No 5""-as per Pro)ecls with impervious area greater than 45% and equal to or Secllon c.2.1? less 1han 65% one or more of 1he following must be appfied to an Yes i ~ area graater 1han or equal to 20% of lite-or 40% of the ""9et"-·---ls""'8 0R for projects greater than 65% imi,en,ious one or more of the following must be No furtber BMPs applied to an impervious an,a greater than or equal to 10% of 8ile required. Nale: or 20% of ta,get tmpen,lou.s surface, whichever Is less: My propo$Bd 1. Full t11fflb-.i (Section SA) COid i8dicii I of roof 2. Limited lnfllbalion (Section C.2.3) ~to 3. Basic Dispersion (Section C.2.4) loa!I drainage 4. Rain Garden (Section C.2.5) SJllffllll1 must be 5. P...-Pavenient (Section C.2.6) via perforalad 6. Rainwater -119 (Se-.. C.2.7) pipe connection 7. "iegeWw Roaf {Section C.2.8) per Section 8. Reduced tn,pervlom Sanrice Credit (Section C.2.9) C.2.11. 9. Native Grvwlll ~n Cn!dlt {Sedion C.2.10) 2005 Sllliilce Water Design Manual 5-11 1124noos . --. 1.l.2 DRAINAGE REVIEW TYPES AND REQUIREMENTS / '6 FIGURE 1.1.2.A FLOW CHART FOR DETERMINING TYPE OF DRAINAGE REVIEW REQUIRED Is the project a single family residan6al or agricultural project that results in "2,000 sf of new impervious surface and meets one of the following criteria? • The project results in ,;10,000 sf of total impervious surface added since 1/8/01 and :;;35,000 sf of new pervious surface, or for sites zoned as RA, F. or A, new pervious surface ,;70,000 sf or 35% of the site, Yes whichever is greater, OR • The project results in ,;4% total impervious surface and :,,15% new pervlous surface on a single parcel site zoned as RA or F, or a single/multiple parcel site zoned as A, and all impervious area on the site, except 10,000 sf of it. will be set back from its natural location of discharge from the site at least 100 fl for every 10,000 sf of total impervious surface? SMAIL PROJECT DRAINAGE JU,VIEVi Section 1.1.2. 1 Note: The project may also be subject to Targeted Drainage Review as determined below. l Does the project result in "2,000 sf of new impervious surface or ~.ooo sf of new pervlous surface, OR is the project a redevelopment project on a parcel Does the project have the characteristics of one or more of the following categories of projects (see the more detailed threshold language on p. 1-14)? or combination of parceis in which No 1. Projects containing or adjacent to a flood, erosion, or steep slope hazard area; projects within a Critical Drainage Area or Landsfide Hazard Drainage Ares; or projects that propose 2:7,000 sf (3 ac if the project is in Smail Project Drainage Review) of land disturbing activity . new plus replaced Impervious >----•• surface totals 2:5,000 sf and whose valuation of proposed improvements (excluding required mitigation and frontage improvements) is >50% of the assessed value of existing 2. Projects proposing to construct or modify a drainage pipe/ditch that is 12" or larger or receives runoff from a 12· or larger drainage pipe/ditch. improvements? 3. Redevelopment projects proposing ;.:$100,000 in improvements to an existing high-use site. Reassess whether drainage review is required per Section 1.1.1 (p. 1-9). Is the project an Urban Planned Development (UPD). OR does tt result in 2:50 acres of new impervious (N;;') surface within a subbasin or multiple subbasins that f-.---... are hydraulically connected, OR does tt have a project site :2:50 acres within a critical aquifer recharge area? Yes 2005 Surrace Water Design Manual 1-11 l Yes TARGETED DRAINAGE REVIEW Section 1.12.2 FULL DRAINAGE REVIEW Section 1.1.2.3 LARGE PROJECT DRAINAGE REVIEW Section 1.12.4 1/24/2005 \ "-lake Youngs \ . ') Groundwater Protection Areas in the City of Renton Public Workll Departmmt, Water Utilit), Eogineeriog Divisioo, J. Wilson, D, Ellis. C. Boatsnum, -------- iT c.,, ,, . . . . r.;;;;, ------1,?UJTDSl t;;ii I' Production v,,r,,11 WeUfteld Capture Zones e SptingbrookSprings O 000 YearCaptun;,Zone [J CityUmils O F111eVearCaptureZone Cedar Valley Sole Source O Tan Year capture Zone Aquifer Project Review Area Aquifer Protection Area Zones StntamllowSoun:eArae @ Zone 1 Cedar Valley Sole Soun:e Aqt.lWer [2 Zone 1 Modified !Z_si Zone 2 N t Reference 11-A Peak Rate Flow Control Standard (Existing Site Conditions) B Flow Contrul Duration Standard (Existing Site Conditions) -Flow Control Duration Standard (Forested Conditions) .... -... i,,_,J Renton C,ty limits ....... L_J Potential Annexation Area Flow Control Application Map N A Plinted 1/14/2010 0 2 Miles ' ' SECTION 3.1 RUNOFF COMPUTATION AND ANALYSIS METHODS FIGURE 3.2.2.A RAINFALL REGIONS AND REGIONAL SCALE FACTORS ST1.1 ST 1.1 ST 1.0 Rainfall Regions and Regional Scale Factors D C:=J Incorporated AreaO -c:::, River/LakeD Major RoadO D 1124/2005 LA 1.0 LA 1.2 !INONOMI ll OUN>~ LA 1.0 2005 Surface Water Design Manual 3-22 3.2.1 KCRTS/RUNOFF FILES METHOD-GENERATING TIME SERIES '; r . .;-. ,:... TABLE 3.2.2.B EQUIVALENCE BETWEEN SCS SOIL TYPES AND KCRTS SOIL TYPES SCS Soil Type scs KCRTS Soil Notes Hydrologic Group Soil Group Alderwood (AgB, AgC, AgD) C TIii Arents, Alderwood Material (AmB. AmC) C TIii Arents, Everett Material /An) B Outwash 1 Beausite(BeC,BeD,BeF) C TIii 2 Bellinoham (Bh) D TIii 3 Brisco! (Br) D TIii 3 Buckley (Bu) D TUI 4 Earlmont !Ea) D TIii 3 Edgewick (Edl C TUI 3 Everett(EvB,EvC,EvD,EwC) A/B Outwash 1 Indianola (lnC, lnA, lnDl A Outwash 1 Kitsap (KDB, KpC, KpD) C TIii Klaus (KsC) C Outwash 1 Neilton INeC) A Outwash 1 Newbern/Ng) B TIii 3 Nooksack fNk) C TIii 3 Nonna (Nol D TIii 3 Orcas (Or) D Wetland Oridia (Os) D TIii 3 Ovall (OVC, OvD, OVF) C TIii 2 Pilchuck /Pc) C TIii 3 Puaet (Pu) D 1111 3 PuvaUuo /Pv) B TIii 3 Raonar /RaC, RaD, RaC, RaE) B Outwash 1 Renton (Rel D TIii 3 Salal (Sa\ C TIil 3 Sammamish (Sh) D Till 3 Seattle (Sk) D WeUand Shalcar (Sm) D TIii 3 Si (Sn) C TIii 3 Snohomish (So. Sr) D Till 3 Sultan (Su) C Till 3 Tukwila fTul D TDI 3 Woodinville (Wo) D TIil 3 Notes: 1. Where outwash soils are saturated or underlain at shallow depth (<5 feet) by glacial 1111, they should be treated as till soils. 2. These are bedrock soils, but calibration of HSPF by King County DNRP shows bedrock soils to have similar hydrologic response to till soils. 3. These are alluvial soils, some of which are underlain by glacial till or have a seasonally high _te, table. In the absence of detailed study, these soils should be treated as till soils. 4. Buckley soils are formed on the low-permeability Osceola mudflow. Hydrologic response is assumed to be similar to that of till soils. 2005 Surface Wmer Design Manual 1/24/2005 3-25 .. EXISTING BASINS 4-23-13 0 40 1 inch = 40 ft [ SHED l --'--••·~'' I ~ ~ . "·••' -·~· .... , . ...;.....;;----"'. ---~---/--1-------iRACT"A" I ~I ~~ I mi!! I . I -}. 65.08' is· LOH $ 4!513 SF' 1:1 1!!1 LOT8 I ii~ I LOT7 ~i I f 4509 sr 4512 sr "' I : I : Jr--., $ IJ_. ;, . . ..· J I ; ~-~03' _:_U__~·~--~ ~ _._. ·~2c_~ : ~ \ ' w w -v( w '---W w .w w I w I--S89"33'01''ii 1 • _ , ' , I I ------Ce----------TIIST1NtllAS111----------. ----. l------I----, --1 . ,__:...l30'----------j-31 j ' 60822 SF = 1.40 ACRES I I }--· (INCLUDES 116TH IMPROVEMENTS) /· i 1 --.... ,. --1 ... ,,,. SH'1l r ----... 73' -T --..... --1 ...... --~ r-1 I I); ~ LOT5 '11· " " z ~ 4!534 Sf" I LOT 4 4st6 sr :. " ~ LOT3 .... ,,. ~ LOT2 ....... I I :. /;! ~ LOT 1 ~?e tr 5' TO BE DtDlCATED AS_~J :geITIONAL I : ~ ,..... I S@.63' I ... . '"·'" L -58.60' _J._ 61,46' ------___i_ ___ ~ ' --' ----' ' _..,. __..._ ....._ I I ~, I ,..J .. 0 PROPOSED BASINS 4-23-13 -----------~---Tt,:--~-;---··---------- ;,J~ . iff: i L017 LOT8 [~zl 4"12SF l SHED\ i)g.95 i;~~ JI : -· i lt---- F-:: ~~ :.-~:. ~:.:. ~·~:. ~·>"" -·-·-·-·"--- 6S.08' 4!513' Sf" I I I · I I I . I . I I i;II I . I r,1 I : j .''/ /'1'.1• / I I I Ii ' . I j ~ .:----'t' ---PAviNc7s15twA K"" -· · t-_-_ -t .. :,··~~ ~1~6~~~-.-_-_--;-... -.---.. -----~= -.-... -.----T~--- 40 1 inch = 40 ft. F: . ------£:----_-_:_-_-_-_ ... --__ -_-:-_-:-_:_-_:_ _:_-_-_-:-_-:-_:_-I---_:_~. r-_-:-_: __ .·.I ....... .__:_--==;.; -K ,..,.- 1 --=-----••~/ --, r••·--/ ~ I' .. I , .1 I 1 1 I I I~ ~ ' ~ I ' "" ~ AL LOT AREA = 3 .~8 SF I • 7 "----.,. "" ( % MAX BLDG COVE 1G PER/ ~ C 4-2-110A = 18, 4. Fv 4 ~ LOT3 ; LOT2y I,.. ,.. 4508 sr SF" ,.. 4514 Sf" r,. I I I /I / / __ ,,a10· _ /_ ••·••· __ / •u•· 4!534 sr LQf 1 46'8 sr LOTS '58,82' ---~-_ _ •• ,a.,,6"'3' __ _ I · I I I I · I · I ti I 1/1 , 11 I ! ~ jl I I I ,L.> Ei.i'ST 0;,L.~i/.j J...I -, ( ll.l:l..vlii:.:. l/1,:::. 1/YifY>Vt.tn:r,) frcofnssr 0~s14 ,: ; r:°d ~dc~1 /; ::.-'..: 1fripr1,!.J(.mer•-~J .:S01w. A 5 B . A~Dcil.Wor:;; S<i!IJAj ?f'AvcllJ ( 5 -;;:; be~l"8,..l. fle?oc..-1) .:: C).72AL lvM, • ,1 vo"P c. TILL " WETPOND DESIGN Project Name: Project Number: Lakeside Fairwood Short Plat 200326 DRAINAGE CRITERIA: RAINFALL METHOD: 2005 King County Surface Water Design Manual King County Runoff Time Series (KCRTS) METHOD OF ANALYSIS: (Section 6.4.1.1 KCSWDM) Step 1) Determine volume factor f. f = 3 Basic: f = 3, Large: f = 4.5 Step 2) Determine rainfall R for mean annual storm R = 0. 039 ft See Figure 6.4.1.A Step 3) Calculate runoff from mean annual storm Vr = (0.9Ai + 0.25Atg + 0.10 Atf + 0.01 Aog) • R Ai= Atg = Atf = Aog = R= Vr= Area of impervious surface Area of till grass Area of till forest Area of outwash grass Rainfall from mean annual storm Vol. runoff from mean annual storm Step 4) Calculate wetpool volume Vb= f Vr f = Volume factor Vr= Vb= Vol. rnnoff frnm mean annual storm Volume of wetpool Step 5) Determine wetpool dimensions a) Determine geometry of first cell Volume in first cell Depth h (1st cell, excl. sed. storage) Required average surface area Provided 1st cell dimensions: width Provided 1st cell ave. surface area or length Provided 1st cell top surface area Provided 1st cell bottom surface area Provided 1st cell ave. surface area Provided Volume m first cell b) Determine geometry of second cell Volume in second cell Depth h (2nd cell, excl. sed. storage) Required surface area Provided 2nd cell dimensions width length 29645 sf 31363 sf 0 sf ____ :;_ ---~O'-sf 0.039 ft 1346 cf 3 1346 ci 4039 cf 1010 cf 4.0 ft 252 sf ____ ft ____ ft ~~1111:: 1089 sf 4356 ___ ___;O:;_cf 0.0 ft #DIV/0! sf ____ ft ____ ft By HEH Date: 4/23/2013 From Step 2 From Step 1 From Step 3 25-35% of total vol., try 25% 3 to 6 feet Aprov'd > Areq'd Aprov'd > Areq'd Aprov'd > Areq'd 65-75% of total vol., try 75% 3 to 6 feet ~-{ j_ i.F 6.4.1 \VETPONDS -BASIC AND LARGE-METHODS OF ANALYSIS FIGURE 6.4.1.A PRECIPITATION FOR MEAN ANNUAL STORM IN INCHES (FEET) ST 1.1 0.54" (0.045'} · · · Incorporated Area ._c:J River/Lake Major Road 0.47" (0.039'} 0.47" (0.039'} NOTE: Areas east of the easternmost isopluvlal should use 0.65 inches unless rainfall data is available for the location of interest 24 The mean annual storm is a conoepwal stonn found by dMding the annual preclpttalion by the total number of storm events per year LA 1.0 LA 1.2 SttOHOMISH co1mn result, generates large amounts of runoff. For this application, till soil types include Buckley and bedrock soils, and alluvial and outwash soils that have a seasonally high water table or are underlain at a shallow depth (less than 5 feet) by glacial till. U.S. Soil Conservation Service (SCS) hydrologic soil groups that are classified as till soils include a few B, most C, and all D soils. See Chapter 3 for classification of specific SCS soil types. 2005 Surface Water Design Manual l/24/2005 6-71 lDLJ(OUIZ. CiJMIY .. tf{i1;!: \JDL .<YJ ___ ~-- 471,..-; 3 I e, -9 .S!::i) s T 1XA !.;; b 1-n-I " ~ ftq -e fl:,!> Ill> /Y\ -e 17t !Je.7 2. C, 0, ZJ,,q 47q t'>DS &Jti '11P~ 4'l>D /0(,,1 C/1;S-/q6/ 4'61 /1!6D !"II 61 IL t'r>I + I rotoq !Db?-Ii I 7v -/ ; I L ', W k,!l;fo W: t_;'_; c Ca';. I/', m<·. : ' ,-,, ' , I U·c,.,-r,".;-,,._·,,:.;_ !_ l ; . " . ,. -,. ' r,,.-r;;:M ::, I · (>,o tr it>-C,. t>/1 /.}, : .·,.,.,. 'DD"(· 'X··-c '··r -'),,'/!, I ~I~ ".,, f-':_::;:-: - , . ' Lakeside Fairwood Short Plat KCRTS Modeling Create a time series and Compute peak flows for conveyance using 15 min time steps Pralo:tioo of P:unoH !iae Series Project location Sea-Tac CotP',lhn;" Series : deve~veyance ts! ieg1cmal fa.le hctm: · 1 ~o let.a Tl'J]e . llstoric Creati11g 15-1.inute Tie Series file I.oadu.,-Tue Series file·C·\J:C_SVDN:C_DUA\STTG15B.rnl 50 :ill Grass U8 acm S::aling !dO loadiag Tile Series File:C:\JC_S1DNC_nm.\Sl'EI15B ml 50 iipervious 0.12 a:I'llll .idd111g Yt:50 Tatal irea l fO acres Peek Disciw9e: 1.75 crs at tU5 Cl! 12:: 2! u 1m Stanng Tae ::e?i.es: File:Ge'lel~.tsl 50 bter the halym TOOLS lo:htle linalvsis Toois Couaid lol«ling Stagc/l)i~ cu:ne:devel~~.tsi Flot frei:('QeOCY mlr,m lD3Peara::m. III C.oeHments ille ~ms File:deorel~.tlean· -U71 Stdfer-" 0.lf.a hoje:t I.ocati1:.r:e8-i&: ~ 1.m Frequm:aes I, Pm saved to File:derelap;o:ooveyance,pb 25.DO 0.%0 ID.DO 0.900 8.00 0 875 I 00 0 800 2 00 0,500 ' 'l'l ,_;a,;"1 .. 1 1• VJ n.91; U!l o.m o.m U!O om 130 0231 ..... "-. • Saft t!l.f,r,~' :JI! l"J, ", " ) ! 25 year peak developed Q=0.971 cfs Create a time series for detention using 1 hour time steps ~~~~'/t1;~~~1~~~~~~~~~1llltl!,i\f~l'fffiil~:}\lf,llWJ5~;! ~ '''""' 1.00 1 fileB rill bi! :rtli!IVnitten in the lmbng Dire::tmy furo:tory:C >;c_svdi"'1tp>t CiF.liTE a IIBl Tie Series Pm!uction of Runoff Tiae S!ries Project locdtiCD ftt.iac I Cmp,hng -: ''"tiog ~I ilogio,al :<al, factor 1.00 ! II,~ Jyp, . listcnc krei:ting brly Tae :ems File ) !J>di'!I I"' r.ri,s Fiie:C 'lC_SWN(_~lllSITFIOR.mf 51 rill fm,st LIO""' :<al"! h:50 Total Ire! UO.:r,s iF"' fu,...,. mm, ,, uo "' Jan y 10 mo Stomg ille ffms File:Wsti.ng.tsf 51 CiEm: a a fae 5imes Pm:luchcm of Raoof! !i1e :eries Proje;t Iooati.cE. : :S--!ac Data ill! HistDl'lC Creati.nq lblrlv Tile Smes Fiie t Cmi,,tiog "''" ~ ts! u:m! 5:ale factor 1.90 I !J>diog Tue "'"' file C\l:_SiltJCJIITllSTffim ml 50 ~ill GI... 0.11 <= Scal10g Yr 50 , wading Tue "'"' File C:'lC_SiMJllTI\SIE!tOR rol 50 11-ia,s 0.18 o:res irldi119 Ir 50 I Yotal lm UO.:r.s ji,,t ~-0.421 ll, at 1:01 on Jan l!o 1991 1 Stomg Tiae :etia.s file:ftic;ed.ts! 50 ' Tie :eries Caip>tel Bl'mI,>lmltO .. , l-311-[C,. !}!a!liaHlm .. Compute existing peak flows i Analysis Tools tam: lDadi..ng Tile Series File:eristmg tsf 50 Flo, r,.,_ loal,sis ~ IT! Co,ffmen~ la, Sen~ File:ensting ts! le,,• -1.111 Stdlle,• 0.111 Pro10:t Jrution:Sea-lac !lsr-~ 1ll I I I 011 JI l/MI J:00 0 OU 18 2.11 I 110 1.oi; II MlilllUO I.Ill II 2.11 IIJO Il.011 13 1m111 23:10 I.II! 11 2.11 0 610 oro1 11 11~YII 1710 1.131 II 2.11 0 110 1.027 JI MlnO 23:10 0011 11 I.II 1.110 1.021 11 12/11/IO 1:11 1.012 II 2.21 1.110 1.061 1 1mm 110 I.OIi 11 1.11 mo 1.111 11 Mini 1:00 0.111 11 I.II I.Ill I.OIi 11 l/11111 I :10 1.111 11 191 1.191 I.OIi 11 !Mini 23:10 1.111 11 Lil 1.171 1.011 1n 11I01nl 11:10 I.Ill 18 111 1110 I.Oil 10 ]/1Vil 19:00 0.011 11 LIi I.IJn 0.021 11 12111m 11:11 I.Ill II LIi 1110 1.011 lo M1m 1:00 0.019 11 LIi 0.191 I.Ill 17 lMVil 110 I.Ill 12 LIi I.Ill 1.011 10 llnl~I 1:10 0.111 ll LIi I.Ill I.~! 11 ll/01~11510 1.111 31 LIi I.Ill 0.010 11 l~l/13 1:00 0.121 31 LIi 1.311 1.111 15 1/11111 U:11 I.Ill J6 Lil 1191 I.Gll 11 Ml/II 1:00 I.Ill 31 Lil 0.171 I.OIi I l/lB/11 20 :01 0.01! Jn 113 1.151 0.011 10 11/lllll I :00 0.021 ~ LIO U.Zll 0.011 II Mlm 12:00 0.011 10 111 1.111 Lill 17 Vllill 11:10 0.011 11 111 1191 l.~I I 1109190 I 00 0011 12 111 0.111 I.Oil I l/05111 2:00 I.Oil ll UB 0151 rn1 31 M111111:00 0.010 II us O.lll 0.021 ]1 3113/IJ 0:00 0.016 II U2 O.ll! 0.001 II 3/llm 1:00 o.m II uo 0.011 D.OII 15 Ml~l 20:00 0.013 17 L08 0.011 0.001 I 2109/11 1 :00 0.013 II LOS 0.051 a.oil 11 1101191 I 00 0.001 II 103 0 .Oll rn1 II llilil811 :00 0.003 50 101 0.011 r..,,,.i Peaks I. Ill 100.00 0.910 .r..,,tal Peaks 0.118 11.00 0.981 .r..,,tal Peaks o.m 15.00 0.960 a.i,,,.i Peaks O.Ull 1000 0.900 li>p,tBI Peaks O.Ool 1.00 0.111 li>p,tal I'm o.m 5.00 0.800 ""Jllllod Peaks 0.131 1.00 0.100 li>p,tod Peaks 0.013 uo 0.111 j)!l'.IIMxx:lm .. , ill001!\I, !:,,,",· 8 .• flQI~!" 1,13~ --. ------.:' 100 yr pre-developed peak Q=0.111 cfs Compute developed peak in flows to flow control facility ~~-.• ,Si"•. c<,' ,•. ' . ,•-?;,: ' . ·:'•-Sc· :'!~ lnoli,1s Tools Cw,,c ~ Ct.pule PillS aml Fla, f"'l'f'l'l!S ioadi,g Tile :<r1es !1le ""toi,,I ~I II Flov F~ balrsis Io,"eam !Ii Crelloc1,.ts Tne "1!ies ille devel{llll 111 lean• ~.661 Stdr.l• I 119 Project l.o:atiot::fa~Tac ~ 1.196 i"ll"'<l!S & Feats ,a,el lo File:develll]Xll pt, II ,,;JI ., 1.m II IMIMHI 1.m II 3.0l mo ~ 1.181 16 1~115516:11 1.211 18 2.81 0.611 0.18! 8 11111,,5 11:11 1.239 II 2.11 I.GIi 1.315 I ~1416816:01 o.m 11 1.51 1.611 0.171 II 11~31!8 15:11 1.125 11 Ul 0.591 1.191 31 1111!10 11:11 0.119 11 1.31 I.Ill 0.181 38 11115!70 8:11 1.111 13 1.11 I.Ill 1.191 I 1mm 1:11 1113 11 1.11 1111 0.161 II 1mm 1:10 OllO 11 1.01 1511 1.105 11 umm 1:11 OIII n 1:% 1.m 0.175 I lMVil ll:11 I.Ill n 1.81 mo 1.171 II IMl/11 11: II 1.116 18 U1 1.m mo JI 8/lVil 1:11 0.113 19 1.15 o.m 1165 ll 1mm 11:01 IW ~ 1.11 I.Ill 0.111 11 1~7911:11 l.l!l 31 1:61 1391 0.111 16 !11MI 11 :II 0111 31 1:11 1311 Ol55 2l llnl/81 ll 01 OJII 33 1:51 1.351 Olbl I lUJU\/81 0:00 rno JI 111 0.3l8 0.1!5 II 11118/Bl 15:11 1.119 35 us 1.311 0.103 19 1m,91 1:11 0.181 36 1:11 1.191 0.161 II 6/0611111 00 1.186 37 131 I lll 0.111 15 1118186 16:11 0.181 38 131 I lll 0.199 6 !OJMf 1:00 1.181 JI uo 0.231 o.m 19 1111188 1:10 I.Ill II 1.27 il.111 0.163 16 8/ll/8117:00 l.llJ II 1.11 1.191 1.111 1 l/11~1 610 I lll 11 Lil 1.171 U80 J ll/11/11 810 1.161 13 1.18 0.151 1.111 JO 11211311110 1.161 II us 0.131 I.Ill 50 1210,91 6:11 0166 15 Lil 0.111 1.141 18 IMMJ11:00 0.163 16 LIO I.Ill 1.112 l1 IMl!91 1:00 1161 11 1:18 0.171 1.111 II l/W96 10 II 1.111 18 1:11 I.Ill 1.111 18 1m,91 6:11 1.m II 1.13 I.OJI 1.111 12 11m~1 1rn 1.111 II Lil 0.111 uaput.t Fm 1.115 IOU.II I.I~ uaputol Feats I.I~ 10.11 OIIO uaputol Feats u,1 25.00 0.160 Ull'"'1 Feats 1.313 10.01 1110 UIJ'l"1 Fm I 301 8.01 D.811 I Ull'tol Fm 1.173 5.11 0.810 UJilll"1 Fm l.lll 2.11 1.110 UJi11"'1 Pm o.m Lll 1.131 I , 1311,x,lullllto... l.!JrllJl,ilH~. {!maa·iiro. :·,~OOIIIII .. p-~!liJ[i~ 100 year post developed peak Q=0.446 cfs inflow to flow control Compute and plot probability exceedence performance curves = = 00 = = :r., ~ = :_;, <I> = "' = <..> .... = = = (XX) "" = 00 rdoutdur c ~rgetdur • .. ~ G· /-, J-. j / Compare durations exceedence ioob Ko:iuie w.lvsis Tools Couand ~ TU! Series File:e:mhng.tsf 50 Co,putmg O,,at101S:Co,plet~ Yr 51 Colputing Dllratiw:Coiplete:1 Yt.50 ~a.lion Ccapariscm AM1lsis Pase file· emti.ng.tsf iB'I File: must tmatlcn i4Jm1S011 Cmpu.te:l and 5nm l).itput File·rotpare.prn Midi '/SIS Tools Couabl f.d.i.t Fa:::ilily I --~!l.ftlJ.[.!.,lll,UJ11.l~tt11li111Il~Jl.111)lrnMna:.J.t .... ,i,111JJ.JJlCi1llll.lJUt~-ffl~Q!Jl~9 ll -Practioo of Tiae---------Oeck oi Tolerar.:e---- Cutof: &se ~~ ~ Pltbabilitv Base lei ~ 1.011 I O.l~-111 1.lli-111 -13.6 I UOE-11 D.011 1.014 -17.7 1.023 I 1.m-11 U7E-111 10.0 I 0.11E-11 1.013 0.014 3.S 1.1111 l.m-111 UIE-11 -1.6 I l.19E-11 I 119 I 019 -ll.7 1.m I o.m-11 011,-111 18.8 1 1.m-11 o.rn 1.131 a.1 I Ill I O !IB-12 Ul!-111 33.1 I l.llE-11 I.Oil 0.011 1.6 I Ol7 I I 6~-03 0.88!-0I 31.1 I o.m-11 1.0!7 0.050 61 0 113 I o.m-13 UIE-01 18.7 I O IIE-113 I.OIi I.OIi U 0.111 I O.JIE-13 UIE-01 -111 I I.IUE-01 I.OIi 0.111 -OJ 1161 I I.IIB-113 O.l~-111 -IU I I.IIB-11, I.OIi 0.111 -5.1 I Ill I 1.111-111 O.IIE-11! -ll.3 I 1.111-13 0.111 0.061 -1.1 I Iii I 1.11!-lli 0.13!-111 -% 11 119!-I! 0.176 0.061 -10.1 1.081 I Ul!-11! o.13!-11 -n I O 11!-I! 0.001 0.011 -11.1 l.081 I UIE-111 O.OOEf00-100.0 I UE-05 0.088 0.075 -lU I091 I U~-111 000!+00 -1100 I 0.13!-111 o.o9! 0.08! -lU W:111J1 i;nsitive ez::un1rm' 0.001 cts; 11.3%) XCU?l'J.Il9' at 0.032 cfs on the Base Data:ensting.tsf :Ind at ll.OJ! cfs CD the iei llata:I'OO'ilt.tsf l!.uiro oegative exc:mim • 0 001 cfs (-21.7%) xcurrag at 0.018 cis III the Base lla.ta:existi11g.tsf :nd at 0.a)( cfs Ill tAe h llata:nbiUs! Although level 2 flow control is based on matching durations, not peaks, peak outflow from the detention facility is computed below. i KCR'l'5 Ccoart: Inter the Ana.lym TOOIS Xaiu1e WlJS;is Tools Ccoald Ccapite PFJ.lS and FllN Fre:iiiercies Loadi.rig iiae !'Enes Fiie:IWlt.tsl 51 Flel' F~ bal~is ~ III Crefficients Tile Series File:l'OOlt.tsf lean= -!.585Stdrtv• Lm Project locatioo.~-Ta: si.,, I.Ill F~1es ~ Pe.us saV&:1 to F1ie:rdcKil.(is ... ~cc·,-,_;~.· o.m 21 Jm/JO 3 II I 019 u, 11 1.31 mo I.Ill 31 1110/70 16.0I I Ill Ul 11 1.11 mo UI 5 1~617112.0D 1.011 I.II 11 Ill 0531 I.Ill 11 lM'il ,:II 1.01, 1.15 15 I.II 1511 U15 16 1110/JI 18:01 1.015 UI 11 1.% U91 1111 ll J/11/1518:11 I015 I.U 11 181 mo I .Ill JI 11~11151010 I 015 1.11 11 181 1.150 I.Ill 50 1n6111 1:01 1.011 I.II 11 1.15 Olli 1011 11 111517118:0I I .Ill UI JI 1.10 I.Ill Ull 18 Im/JI 13:01 I.Oil U2 31 1.61 I.Ill 1.151 6 ll/1111110:01 I.Ill Ul JI 151 0111 1.011 30 11/30/10 11:00 I 011 I.II ll 1.51 0.150 0011 13 10/06111 11:01 011, I.II 31 UI 0.130 I.OIi 11 1/18/13 l:01 I 014 Iii l5 U5 OllO I .011 41 lMJ/il 1:01 I .011 U5 Ji JU 0.111 0011 13 Il!l2/U 2:0a I 011 l.11 31 i.37 0.171 0.017 11 J/lMi ll:00 I C1J 115 31 1.31 1.151 I Oil ~ 1111(111 I :00 I Ill UI JI lll o.m I.Ill 41 1MM1 !:00 I.Ill Ul II 1.11 1111 0011 '5 ll/MI 1:00 I.Ill l.11 11 1.11 o.m I Oil 1/11110 llOO I 011 1.18 II 1.11 0.171 I.Oil I 11111/ll H:00 I.Ill l.11 II 1.18 1.151 0011 11 liMI 1:01 1111 1.11 II 1.15 0.131 I.Ill 11 )/1,/1) 1:01 0011 l.11 Ii 1.11 0.111 I.Ill 19 1110/ll I :00 0.011 l.01 i; 1.ll I.Ill I 011 11 11111111 1 :00 I Ill 1.15 11 1.01 0.011 I 010 I 1/IMI I 00 I.Ill 1.15 1B 101 0. 051 I.I~ I l!OM111:00 0 010 l.l2 ll 1.0) I. Ill O.Oll lO lnl/11 1:00 0.010 111 5i 1.01 0.111 t.i Peaks 0.11! I .7l 100.00 0.110 I UII I.JI 51.01 0.110 O.ll81 I.JO 11.00 0.160 0.160 U4 10.00 0.101 I.OSI 181 1.00 o.m 0.0!5 1.51 1.01 0.101 0 016 UI I 00 1101 o.m I.II 1.11 0.131 . .. :f:l ~ I ~ ~ ·'''" 0Irtxix:.fm,~ .. , ell-L, • !j00\15.itn: ... jmm -~<ffis..,,:::T,,---~~P-1.!~,Jf!l 1,$• 100 year Post developed outflow from flow control facility= 0.119 cfs Detailed tabular summary of the pre and post developed conditions Item Pre-developed Post developed pond outflow ! Till forrest 1.4 ac (includes 1161h improvements) i Till grass 0.72 ac (includes 1161h improvements ' Impervious 0.68 ac (includes 1161h improvements 100 year peak flow 0.111 cfs 0.119 cfs 50 year peak flow 0.098 cfs 0.099 cfs 25 year peak flow 0.084 cfs 0.081 cfs 10 year peak flow 0.067 cfs 0.060 cfs 5 year peak flow 0.053 cfs 0.045 cfs 2 year peak flow 0.034 cfs 0.026 cfs 1.3 yr pk flow 0.023 cfs 0.016 cfs KCRTS Documentation File Retention/Detention Facility Type of Facility: Side Slope: Pond Bottom Length: Pond Bottom Width: Detention Pond 2.22 H:lV 73.25 ft 23.06 ft Pond Bottom Area: Top Area at 1 ft. FE: 1689. sq. ft 5439. sq. ft vs 1689 measured@ el 481.7 vs 5431 measured@ el 488.4 Effective Storage Depth: Stage O Elevation: Storage Volume: Riser Head: Riser Diameter: Number of orifices: Orifice # Height (ft) 1 0.00 2 4.05 3 4.35 0.125 acres 5.70 ft 481. 80 ft 17791. cu. ft 0.408 ac-ft 5.70 ft 12.00 inches 3 Diameter (in) 0.50 1.00 0.88 Full Head Discharge (CFS) 0.016 0.035 0.024 Top Notch Weir: None Outflow Rating Curve: None Pipe Diameter (in) 4.0 4.0 Stage Elevation Storage Discharge Percolation (ft) (ft) (cu. ft) (ac-ft) (cfs) (cfs) 0.00 481.80 0. 0.000 0.000 0.00 0.01 481.81 17. 0.000 0.001 0.00 0.02 481.82 34. 0.001 0.001 0.00 0.03 481.83 51. 0.001 0.001 0.00 0.04 481.84 68. 0.002 0.001 0.00 0.05 481. 85 85. 0.002 0.001 0.00 0.16 481.96 27 6. 0.006 0.003 0.00 0.27 482.07 472. 0. 011 0.004 0.00 0.38 482.18 673. 0.015 0.004 0.00 0. 49 482.29 880. 0.020 0.005 0.00 0.61 4 82. 41 1111. 0.026 0.005 0.00 0. 72 482.52 1329. 0.031 0.006 0.00 0.83 4 82. 63 1553. 0.036 0.006 0.00 0.94 482.74 1782. 0. 041 0.007 0.00 1. 05 482.85 2017. 0. 04 6 0.007 0.00 1.16 482. 96 2257. 0.052 0.007 0.00 l.28 483.08 2526. 0.058 0.008 0.00 1. 39 483.19 2778. 0. 064 0.008 0.00 1. 50 483.30 3037. 0.070 0.008 0.00 1. 61 483.41 3301. 0. 07 6 0.009 0.00 1. 72 483.52 3571. 0.082 0.009 0.00 1. 84 483.64 3873. 0. 08 9 0.009 0.00 1. 95 483.75 4155. 0.095 0.009 0.00 2.06 483.86 4444. 0.102 0.010 0.00 Surf rea (sq. ft) 1689. 1693. 1698. 1702. 1 706. 1710. 1758. 1806. 1854. 1903. 1957. 2007. 2057. 2108. 2160. 2212. 2269. 2321. 2375. 2429. 2483. 2543. 2598. 2654. ·/ t, '] {: 2.17 483.97 4739. 0.109 0.0:iO 0.00 2710. 2.28 484.08 5040. 0 .116 0.010 0.00 2766. 2.39 484.19 5348. 0.123 0.010 0.00 282'. 2.51 484.31 5690. 0.131 0.011 0.00 2886. 2.62 484.42 6011. 0.138 0.011 0.00 2945. 2.73 484.53 6338. 0 .14 6 0. 011 0.00 3003. 2.84 484.64 6672. 0.153 0. 011 0.00 3062. 2.95 484.75 7012. 0.161 0.012 0.00 3122. 3.06 484.86 7359. 0.169 0.012 0.00 3182. 3.18 484.98 7744. 0.178 0.012 0.00 3248. 3.29 485.09 8105. 0.186 0.012 0.00 3309. 3. 40 485.20 8472. 0.194 0. 013 0.00 3371. 3.51 485.31 8847. 0.203 o. 013 0.00 3433. 3. 62 485.42 9228. 0.212 0.013 0.00 3495. 3.74 485.54 9651. 0.222 0. 013 0.00 3564. 3.85 485.65 10047. 0.231 0. 013 0.00 3627. 3.96 485.76 10449. 0.240 0. 013 0.00 3691. 4. 05 485.85 10784. 0.248 0. 014 0.00 3744. 4.06 485.86 10821. 0.248 0.014 0.00 3750. 4. 07 485.87 10859. 0.249 0.014 0.00 3756. 4.08 485.88 10896. 0.250 0.015 0.00 3762. 4.09 485.89 10934. 0.251 0. 017 0.00 3768. 4.10 485.90 10972. 0.252 0.019 0.00 3774. 4 .11 485.91 11010. 0.253 0.021 0.00 3779. 4.12 485.92 11047. 0.254 0. 021 0.00 3785. 4 .13 485.93 1108 5. 0.254 0.022 0.00 3791. 4.14 485.94 11123. 0.255 0.022 0.00 37 97. 4. 26 486.06 11583. 0.266 0.026 0.00 3868. 4.35 486.15 11934. 0.274 0.029 0.00 3922. ' "' 486.16 11973. 0.275 0.029 0.00 3928. ':I • .::iu 4.37 486.17 12012. 0.276 0.030 0.00 3934. 4.38 486.18 12052. 0. 277 0.031 0.00 3940. 4.39 486.19 12091. 0.278 0.032 C.00 3946. 4.40 486.20 12131. 0.278 0.035 0.00 3952. 4.41 486.21 12170. 0.279 0.036 0.00 3958. 4.42 486.22 12210. 0.280 0.036 0.00 3964. 4. 53 486.33 12 64 9. 0.290 0.042 0.00 4031. 4.65 486.45 13137. 0.302 0.047 0.00 4104. 4. 7 6 486.56 13593. 0.312 0.051 0.00 4171. 4.87 486.67 14055. 0.323 0.055 0.00 4239. 4. 98 486.78 14525. 0.333 0.058 0.00 4307. 5.09 486.89 15003. 0.344 0.061 0.00 4 37 6. 5.21 487.01 15532. 0.357 0.064 0.00 4452. 5.32 487.12 16026. 0.368 0. 067 0.00 4522. 5.43 487.23 16527. 0.379 0.069 0.00 4592. 5.54 487.34 17036. 0.391 0. 072 0.00 4663. 5.65 487.45 17553. 0.403 0.074 0.00 4734. 5.70 487.50 17791. 0.408 0.075 0.00 4 7 67. 5.80 487.60 18271. 0.419 0.385 0.00 4832. 5.90 487.70 18757. 0.431 0.950 0.00 4898. 6.00 487.80 19250. 0.442 1. 680 0.00 4 964. 6.10 487.90 19750. 0.453 2.480 0.00 5031. 6.20 488.00 20256. 0.465 2. 760 0.00 5098. 6.30 488.10 20770. 0.477 3.020 0.00 5165. 6. 40 488.20 21290. 0.489 3.250 0.00 5233. 6.50 488.30 21816. 0.501 3.470 0.00 5301. 6.60 488.40 22350. 0 .513 3. 680 0.00 5370. 6.70 488.50 22890. 0.525 3.880 0.00 6. 80 488.60 2 34 38. 0.538 4. 0 60 0.00 6.90 488.70 23992. 0.551 4.240 0.00 7.00 488.80 24553. 0.564 4.410 0.00 7.10 488.90 25122. 0. 577 4.570 0.00 7.20 489.00 25697. 0. 590 4. 730 0.00 7.30 489.10 26279. 0.603 4. 8 90 0.00 7.40 489.20 26869. 0. 617 5.040 0.00 7.50 489.30 27 4 66. 0.631 5.180 0.00 Hyd Inflow Outflow Peak Storage Target Cale Stage Elev (Cu-Ft) (Ac-Ft) 1 0.42 0.11 0.06 5.20 487.00 2 0.24 ******* 0.07 5.40 487.20 3 0.27 ******* 0.07 5.30 487.10 4 0.27 ******* 0.05 4. 79 486.59 5 0.36 ******* 0.04 4.48 486.28 6 0.25 ******* 0.03 4.27 486.07 7 0.15 ******* 0.02 4.19 485.99 8 0.16 ******* 0.01 3.76 485.56 ---------------------------------- Route Time Series through Facility Inflow Time Series File:developed.tsf Outflow Time Series File:rdout Inflow/Outflow Analysis Peak Inflow Discharge: Peak Outflow Discharge: Peak Reservoir Stage: Peak Reservoir Elev: 0.422 0.084 5.70 487.50 CFS CFS Ft Ft at at Peak Reservoir Storage: 17805. Cu-Ft 0.409 Ac-Ft 15475. 16369. 15 92 9. 13722. 12 441. 11630. 11306. 9707. 6:00 on 20:00 O!l Flow Duration from Time Series File:rdout.tsf 0.355 0.376 0.366 0.315 0.286 0. 267 0. 260 0.223 Jan 9 in Feb 9 in Cutoff Count Frequency CDF Exceedence Probability CFS % % % 0.001 214206 48.905 48.905 51. 095 0. 511E+00 0.004 39988 9.130 58.035 41. 965 0.420E+OO 0.006 55180 12.598 70.633 29.367 0.294E+OO 0.008 52743 12.042 82.675 17.325 0.173E+OO 0. 011 37166 8.485 91.160 8.839 0.884E-Ol 0.013 23060 5.265 96. 425 3.575 0.357E-01 0.015 12039 2.749 99.174 0.826 0.826E-02 0.018 242 0.055 99.229 0.771 0.771£-02 0.020 193 0.044 99.273 0.727 0.727E-02 0.022 516 0 .118 99.391 0.609 0.609E-02 0.025 627 0.143 99.534 0.466 0.466E-02 0.027 476 0.109 99.643 0.357 0.357E-02 0.029 421 o. 096 99.739 0. 261 0.261E-02 0.032 112 0.026 99. 765 0.235 0.235E-02 0.034 43 0.010 99.774 0.226 0.226E-02 0.036 128 0.029 99.804 0.196 0.196E-02 ~ .' 0 ': 5439. 5508. 5578. 5648. 5719. 5790. 5861. 5933. 6005. 1990 1951 --- ;'i r, a--: 0.039 146 0.033 99.837 0.163 0.163E-02 0.041 95 0.022 99.859 0.141 0.141E-02 0.043 107 0.024 99.883 0.117 0. ll 7E-02 0.046 97 0.022 99.905 0.095 0.947E-03 0.048 80 0.018 99.924 0.076 0.765E-03 0.050 53 0.012 99.936 0.064 0.644E-03 0.053 57 0.013 99.949 0.051 0.514E-03 0.055 36 0.008 99.957 0.043 0.432E-03 0.057 41 0.009 99. 966 0.034 0.338E-03 0.060 45 0.010 99.976 0.024 0.235E-03 0.062 25 0.006 99.982 0.018 0 .178E-03 0.065 26 0.006 99.988 0.012 0 .119E-03 0.067 9 0.002 99.990 0.010 0.982E-04 0.069 22 0.005 99.995 0.005 0.479E-04 0.072 8 0.002 99.997 0.003 0.297E-04 0.074 7 0.002 99.999 0.001 0.137E-04 0.076 5 0.001 100.000 0.000 0.228E-05 0.079 0 0.000 100.000 0.000 0.228E-05 0.081 0 0.000 100.000 0.000 0.228E-05 0.083 0 0.000 100.000 0.000 0.228E-05 IC,) l-/[_ Yv/A.'X [)OiF'..lltO F{J;/1 r:o;J[. -PEAL. 0:.xrc./XG ;),\ii{l\!Lb, a O,DS" :'"': 'de :\~AL. T,:.-;: F/.\u_ IL.,__JJ'DE.1 ;c)t_ C\a')) < · ,c_ CF; -:')L I OD'1 fL G O ::;V(.:L1) reD a 0. 4H, C..Fs b,44 \. : H•h Mltv Ws c:. 4£7, + ! oo •trL {,; D "V = 0 A~ ~ '.:' P'', Pbf< Vk ~· , ~ 'el St, TOP vr ,::1-IAl::IL ,·, f· ; . [, ! .:z k &,, b 4-4l. OL SECTION 5.3 DETENTION F ACJLJTIES 1/24/2005 Riser Overflow The nomograph in Figure 5.3.4.H may be used to determine the head (in feet) above a riser of given diameter and for a given flow (usually the I 00-ycar peak flow for developed conditions). FIGURE 5.3.4.H RISER INFLOW CURVES '5' C 0 " .. "' ~ 8. -.! 10 " :l:i :, .!!. 0 ....-------,,-1 r ·----. _. HEAD IN FEET (measured from crest of riser) ,. ___ __;__ Q...,,=9.739 DH 312 I a.....,.=3.782 D2 H 112 10 Q in cfs, D and H in feet Slope change occurs at weir-orifice transition I 2005 Surface Water Design Manual / ' ··-._ .. V. CONVEYANCE SYSTEMS ANALYSIS AND DESIGN Conveyance systems will include catch basins and pipes. KCRTS modeling using the 15 min time step for inflow to the pond indicate 25 year peak flows of0.971 CFS and I 00 year peak flow of 1.51 CFS. While the 25 year flow design is required for new conveyance systems, the backwater analysis uses the I 00 year flow for those portions of the storm system from the detention pond outflow to the discharge point from the site as a conservative approach which assumes the pond is full at the time of the I 00 year event. Note that projected 100 year outflow from the pond is substantially less at approximately 0.119 CFS. While the subject site will consist of 1.0 acres after ROW dedication, the 1.4 acre contributory drainage basin includes portions of 116th Ave SE and this area is used to derive flows. Using the Rational Method as a quick check: A= 1.4 acre Area Imperv = 0.68 acre, Area Pervious = 0.72 acre Cave= (0.68 ac x 0.9) + (0.72 ac x 0.2) = .756 (Cn lawn/landscape= 0.2) hs=2.5" Q=CIA = 0.756 x 2.5 x 1.4 =2.46 cfs A 12" smooth bore (n=0.012)@0.3% slope yields 2.2cfs at 3.lfps full flush velocity. 2.2 cfs>0.971 cfs : o.k. full flow velocity= 3. !fps which exceeds 3fps min velocity: o.k. Since the rational method tends to over-estimate peak flows for larger areas, conveyance backwater analysis using the KCRTS modeling flows is providedA backwater analysis has been prepared using Hydraflow Software by lntellisolve which demonstrates the adequate conveyance capacity. Tail water elevations were assumed to be negligible at the rock pad outflow discharge point but were assumed to be the 100 year pond level at elevation 487.4 for downstream conveyance systems. 0 1 inch ! I . . I ,. ' LA~8SJDE F AIRWOOD .·· p~-~, .. TJ/,.5/21 /1 J ' ~ ' ! ,/ ! i ' i ! --"' .. '· . ' ·~ 15' . . ~RAINAGE & E~::ENf , , LOT8 ! : 4509 SF I . I I ' '!.I i 15' SAN I "-J_ SE'JER : EASEMENT I s•; ADS CONNECT ROOF OCVINSPOUT (Ti1'1CAL) CLEANOOT (Ti1'1CAL) ·."•:,: i' i(l8 ~ ' ' , ' !\'PE IH8 TE 49o:rr- lE 481.60 I , EMERGENCY O;{RfLOW . ·' .\. ..TYPE II C8 W/ BIRlicAGE " a\ 1E 487.S2 IE "85,02 , I !.I r I{ ,, hW~l" 0 i'5J"l JU '\.fV.' 6' BLACK ~NYL COA TEO CHAJN LINK FENCE \II \ I' LOf 6 4513' SF T/DETENTION PONO 1WETPON0 477.5 TO 481. VOL REOD = 4039 CF VOL PROVIDED = 4179 DETENTION 481. 7 TO 48' VOL REQD/Pl)!)VIDEO = .".-r. ·~ .- '3j~J ,) . 3 •100 J I J,, 1 l ) . . . cl,Jl;~,l°'!J ' ~" .. <;,.;. LJ .1 , ~ "t. .. .,/~~t) ' \ 1 :I 0 Ao ,1. I L LOT5 4534 SF l LO'l; 4 1 4516 SF (.''.;,'( L ("fa! 1 ··,._.-, ")_.; '! I I I I I I I I I I I I C8#4 -m>E I STA 2+09.60 -9.17'LT TE 489.35 IE 488.85 LOT3 4514 SF I I L0T 2 4508 SF !J '.;;;;a;;ii -~~ LOf 1 4678 SF 5' TO BE DEDICATED ADDITIONAL ROI< i .L; \ .,.\.,-, J ~~./ Lakeside Fairwood Short Plat KCRTS Modeling Create a time series and Compute peak flows for conveyance using 15 min time steps Cilltt a Def Tiie Series Prm:tica of ilb:lff Tiae :ieues Project Imtim ~Tac ~iiq Seri.m : deve.lm.,..._..,,,_..,~.to lleqitllill S:al.11 iac\ar : l . 1111 !eta Tvre · Historic Crel1iig IJ-linte Ti.le Seri.es File ~ TUI: !:en.es File:C:'1.C_SWI\IC_Dln\STTG15lrnf 50 Till Grnss O.U ~ 5:alir,i; Yr:Sll Jo,ii,g Tie Series Fild,l!C_SIINCJllil\SIIllll.ml 10 1-ims I. 72 aaes l,lli,i Yt,10 Total ma · l.10 acres Feai ~-1.11 er; al !UI "' ii,: ll n 1"6 Stllrl!IIJ Tie~ File:~.tsl 50 Enter tbe .iulysis-TOOlS bluie balysis Tools Cmml loadilgS--,..,~~I n .. ,_ llal,m IogF,arsa, ill Caeflicists Tiae £eries file:de9elqiedca~. tm= -ti. 371 5*' G .!ii Project lcat1m:S&-Tac ~ 1.m !~ 4-Peal:s-saved to File:~.pk:s ···----·-· $H1!1ifit·i'.'.J'.f: 1811 I 10/04/9? lt:15 1.111 -10 LO! 0.011 """"" l'eal, ® WU l.lll r..,,tol l'eal, l.22 10.00 me """"" l'eal, 4llt> u U61 """"" l'eal, I l!H UH """"" l'eal, 0.111 1.01 o.m """"" l'eal, I.Ill I.II 0.811 """"" l'eal, OJ~ 2.~ I.Ill --0.33' uo o.m ..... LI-" -· .... r l ' ~jj (1) (2) (3) (4) (5) (6) Pipe Outlet Inlet Segment Q "n" Elev. Elev. CB to CB (els) Value (ft) (ft) OUTLET 5 1.51 0.012 481.00 4S1.60 5 CMH 1.51 0.012 481.60 481.70 CMH POND 1.51 0.012 481.70 480.00 POND 1 I 0.97 0.012 479.70 486.35 0.012 486.35 486.67 0.012 486.67 486.65 0.012 I 491.49 I 491.67 (7) (8) (9) Barrel earrei Barrel Vel. Am Velocity Head (sq it (fps) (ft) 0.79 1.92 0.06 0.79 1.92 0.06 0.79. 1.92 0.06 0.79 1.24 0.02 o}§ 1.24 0.02 0.19 . 1.24 0.02 0.79 1.24 0.02 (10) lW Elev. (ft) 482.00 482.75 482.95 487.40 487.48 487.74 I 487.48 I (11) Friction Loss (ft) 0.191132 0.051575 0.042474 0.026972 0.066979 0.011267 0.011267 --~., \ .. (13) (14) (15) (16) (17) (181 Outlet Inlet Appr. Bend Control conrol Vol. Head Elev. E1ev. Head Loss (ft) (ft (fl) 482.89 ij6;141 0.06 482.88 4~2,52 0.06 483.08 .1\80.85. 0.06 487.46 ~QJ.00 0.02 487.71 481'40 0.02 487.79 487:38 0.02 492.71 492.40 0.02 (19) (20) June. Head HW Ground Loss Elev. Elev. (fl) (fl) 0.00 482.75 0.00 482.95 0.00 483.15 0.00 487.48 0.00 487.74 0.00 487.82 0.00 492.75 0111. (fl) o. ft 7.25 1.00 7.05 1.00 6.85 1.00 0.00 6.69 1.00 1.61 1.00 1.53 1.00 0.00 1.42 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 p 3.14 3.14 3.14 0.00 3.14 3.14 3.14 0.00 3.14 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 .. \., -. \ \ Kj C y slope -HW inlet or outlet pipe surch. 0 0.0398 0.67 0.0048 0.81 0.81 482.69 outlet -7.27 yes 0 0.0398 0.67 0.0029 0.82 0.82 482.88 outlet -0.25 yes 0 0.0398 0.67 -0.0607 0.85 0.85 483.08 outlet -2.15 yes 0 0.0398 0.67 0.1547 d.65 0.65 487.46 outlet -0.13 yes 0.0030 -0.0011 0.0100 -\, i .. s, VI. BASIN AND COMMUNITY PLANNING AREAS (N.A.) Vil. OTHER PERMITS (N.A.) VII. EROSION/SEDIMENTATION CONTROL DESIGN Esc Plan Analysis and Design Erosion Control BMP' s shall consist of a construction limits, rock construction entrance, silt fencing and catch basin protection for downstream facilities. A full ESC design is provided as Sheet C2 of the construction documents. Construction Phasing -In order to prevent erosion and trap sediments within the project site, the following BMPs will be used approximately as shown on the ESC plan and in the order described below: • Clearing limits will be marked by fencing or other means on the ground. • The catch basin insert shown on the plans shall be installed. • At the driveway area the rocked construction entrance shall be installed. • Runoff will not be allowed to concentrate and no water will be allowed to point discharge onto the slopes. • Silt fencing will be placed along slope contours at the down-slope limit of clearing. • Temporary cover measures will be used as required per the ESC notes for wet-season construction. • Sediment trap and ditch conveyance are included for the project. SWPPS (Surface Water Pollution Prevention Plan) Project Description-The Proposed Development consists of 8 lot single family residential project located at 18624 -I 16th Ave SE on approximately 1.0 acres. Existing Zoning is R-8. The proposed residential development requires a new public access road (SE 186th Pl) and Frontage Road Improvements (116th Ave SE) consisting of new sidewalks, curb and gutter and storm drainage. The site consists of a total of 1.0 acres after ROW dedication and is currently developed as a single-family residence with garage, gravel driveway and landscaped yard. The proposed development will create 29,645 s.f. of new impervious surface. The Geotechnical Engineering Study by Geotech Consultants, page 2, dated 6/19/2009 ( see appendix) indicates up to 7 feet of silty sand fill overlaying glacial till. There are no indications of closed depressions on the property. The anticipated volumes of grading cut and fill that are proposed are as follows: Cut< 900 CY Fill< 400 CY Erosion Specialist. The project civil engineer may be contacted in the event that construction observation is required. Contact information is as follows: Civil Engineer: Hagenson Consultants, LLC 6484-48th Ave SW Seattle, WA 98136 Contact: Hal Hagenson, P .E. Ph: 206-938-6168 Email: H.Hagenson@Comcast.net Existing Site Conditions: The property has an existing single-family residence, garage, gravel driveway and landscaped yard. Existing Grades slope generally towards the center. Site slopes vary between 2 and 40 percent. There are no indications of closed depressions on the property. Adjacent Areas: There are no immediate adjacent areas, including streams, lakes, wetlands, residential areas and roads that might be affected by the construction project. Drainage from the site Sheet flows northwesterly towards the adjacent single family residential parcel. Critical Areas-There are no critical areas in the site vicinity that would be impacted by the development other than the small steep slope area which is subject to a critical area exemption and may be developed and regraded and category 3 wetlands which are exempt and allowed to be developed. Soil: The Geotechnical Engineering Study by Geotech Consultants, page 2, dated 6/19/2009 (see appendix) indicates up to 7 feet of silty sand fill overlaying glacial till. Indications of perched groundwater tables are therein noted at between 4 and 7 feet depth Site soils are classified in SCS mapping as Alderwood gravelly sandy loam (AgC), 6 to 15% slopes, hydrologic class C, till soils. Alderwood series have slow permeability; runoff potential is slow to medium and a moderate to server erosion hazard. Potential Erosion Problem areas: The site is slopes moderately with alderwood soils which have moderate to severe erosion hazard. Twelve Elements -Refer to the attached erosion and sedimentation control plan for each BMP and its location. Construction Phasing: In order to prevent erosion and trap sediments within the project site, the following BMPs will be used approximately as shown on the ESC plan and in the order described below: • Clearing limits will be marked by fencing or other means on the ground. • The catch basin insert shown on the plans shall be installed. • At the driveway area the rocked construction entrance shall be installed. • Runoff will not be allowed to concentrate and no water will be allowed to point discharge onto the slopes. • Silt fencing will be placed along slope contours at the down-slope limit of clearing. • Temporary cover measures will be used as required per the ESC notes for wet-season construction. • Sediment retention and flow control will be accomplished in the onsite detention pond, which will be cleaned before final acceptance. • Construction Schedule -The project construction will initiate in the fall of 2013 and will take approximately three to 6 months to complete. Financial Ownership Responsibilities: Bond information is provided in the TlR. Engineering Calculations: There are no required calculations. (-b~) Lr-= qy x T (...- • / . I f. ;._ =-l,. ;, Jt:1n.J-cJ (_M11: ,:1.,-/ocv~-t-CJ ZDD/, / Ir,, e, x (,,() -= -"/\ {l~ j ,-,~Jx I ' /. !~/ 1'-r'.(, if 'l -U,0'1·\ , •"' c,v , f, 'f =: -'-f / 'Cf =.-; I • - IX. BOND QUANTITIES WORK SHEET, RETENTIONIDETENTION FACILITY SUMMARY SHEET AND SKETCH, AND DECLARATION OF COVENANT City of Renton TREE RETENTION WORKSHEET 1. Total number of trees over 6" in diameter1 on project site: 1. ---'4=0 ____ trees 2. Deductions: Certain trees are excluded from the retention calculation: Trees that are dead, diseased or dangerous2 ____ trees Trees in proposed public streets 19 trees Trees in proposed private access easements/tracts ____ trees Trees in critical areas3 and buffers trees Total number of excluded trees: 3. Subtract line 2 from line 1: 2. __ 1""9""----trees 3. __ _,,2,_,1 __ trees 4. Next, to determine the number of trees that must be retained 4 , multiply line 3 by: 0.3 in zones RC, R-1, R-4, or R-8 0.1 in all other residential zones 0.05 in all commercial and industrial zones 4. __ .::c6.,_,.3,_ __ trees 5. List the number of 6" or larger trees that you are proposing 5 to retain 4: 5. 46--/3 trees 6. Subtract line 5 from line 4 for trees to be replaced: (If line 6 is less than zero, stop here. No replacement trees are required). 6. ..a;J-1,,. 7 trees 7. Multiply line 6 by 12" for number of required replacement inches: 7. ______ inches 8. Proposed size of trees to meet additional planting requirement: (Minimum 2" caliper trees required) 8. ------inches 9. Divide line 7 by line 8 for number of replacement trees6 : (if remainder is .5 or greater, round up to the next whole number) 1 · Measured at chest height. per tree 9. ______ trees 2 · Dead, diseased or dangerous trees must be certified as such by a forester, registered landscape architect, or certified arborist, and approved by the City. 3 · Critical Areas, such as wetlands, streams, floodplains and protected slopes, are defined in Section 4-3-050 of the Renton Municipal Code (RMC). 4 · Count only those trees to be retained outside of critical areas and buffers. 5 The City may require modification of the tree retention plan to ensure retention of the maximum number of trees per RMC 4-4-130H7a C:\Documents and Senings\Hal\My Documents\AutoCADD Documentsllob Nos\Hc\2012\201210 Bui Renton\Jaeger Engineering Files\Files Transferred 2-15-12 by Litchfield Engineering\Lakeside\Prelim IT reeRetention Worksheet.docx 12/08 Site Improvement Bond Quantity Worksheet @) King County Department of Development & Environmental Services 900 Oakesdale Avenue Southwest Renton, Washington 98055-1219 206-296-6600 TTY 206-296-7217 Project Name: Lakeside Fairwood Short Plat Location: 18624 116th Ave SE, Renton, WA Clearing greater than or equal to 5,000 board feet of timber? ~~~~~~ yes If yes, Forest Practice Permit Number: (RCW 76.09) Page 1 of 9 x no For alternate formats, call 206-296-6600, Date: 5/3/2013 Project No,: 201210 Activity No,: Note: All prices include labor, equipment, materials, overhead and profit Prices are from RS Means data adjusted for the Seattle area or from local sources if not included in the RS Means database, Renton BOND QUANTITY WORKSHEET 2011-06-06.xlsx Check out the DDES Web site Unit prices updated: 02/12/02 Version 04/22/02 Report Date: 513/2013 Site Improvement Bond Quantity Worksheet Backfill & compaction-embankment IESC-1 I I $ 5.62 I CY Check dams, 4" minus rock IESC-2 I SWDM 5.4.6.3 I$ 67.51 Each 4 Crushed surfacing 1 1/4" minus !ESC-3 I WSDOT 9-03.9(3) I$ 85.45 CY Ditchinl! IESC-4 I I $ 8.08 CY 20 Excavation-bulk IESC-5 I I $ 1.50 CY Fence, silt IESC-6 I SWDM 5.4.3.1 I $ 1.38 LF 484 Fence, Temporary (NGPE) I ESC-7 $ 1.38 LF Hydroseeding I ESC-8 SWDM 5.42.4 $ 0.59 SY 4000 Jute Mesh I ESC-9 SWDM 5.4.2.2 $ 1.45 SY Mulch, by hand, straw, 3" deep ESC-10 SWDM 5.42. 1 $ 2.01 SY Mulch, by machine, straw, 2" deep ESC-11 SWDM 5.42. 1 $ 0.53 SY Piping, temporary, CPP, 6" ESC-12 $ 10.70 LF Piping, temporary,CPP, 8" ESC-13 $ 16. 10 LF Piping, temporary, CPP, 12" ESC-14 $ 20.70 LF Plastic covering, 6mm thick, sandbagged ESC-15 I SWDM 5.42.3 $ 2.30 SY Rip Rap, machinej)laced; slopes ESC-16 I WSDOT 9-13.1(21 $ 39.08 CY Rock Construction Entrance, 50'x15'x1' ESC-17 I SWDM 5.4.4.1 $ 1,464.34 Each Rock Construction Entrance, 100'x15'x1' ESC-18 I SWDM 5.4.4.1 $ 2,928.68 Each Sediment_p_ond riser assembly ESC-19 I SWDM 5.45.2 $ 1,949.38 Each Sediment trap, 5' high berm ESC-20 I SWDM 5.4.5. 1 $ 17.91 LF Sed. trap, 5' high, rlprapped spillway berm section IESC-21 I SWDM 5.4.5. 1 I $ 68.54 0.51 6.03 Seeding, by hand ESC-22 SWDM 5.4.2.4 .L!__ Soddinl!, 1" d_e_e_e, level ground ESC-23 SWDM 5.4.2.5 I $ Sodding, 1"deep, sloped ground IESC-24 I SWDM 5.42.5 I $ 7.45 TESC Supervisor IESC-25 I I$ 74.75 I HR Water truck, dust control ••• .... lt:· .. ·IN·,.•·· '.c~1"•·1iffi:: ·,·,·•:9 .Y,Y,l:'l. .. J::;1. .. ~ !L "-'"-0 ·"',. --• -, ,,; • Each ESC SUBTOTAL: 30% CONTINGENCY & MOBILIZATION: ESC TOTAL: COLUMN: Page 2 of 9 Renton BOND QUANTITY WORKSHEET 2011-06-06.xlsx Check out the DOES Web site - Ct!M. 270 162 668 2360 1464 1949 ------ $ 6,873.28 $ 2,061 98 $ 8,935.26 A Unit prices updated: 02/12/02 Version: 04/22/02 Report Date: 5/3/2013 ~1te Improvement Bond Quantity Worksheet •·-,'-• •··."t:,;,,F -'1f1,:,-f:c·.3$,:"';<,@$/'ci"•i: ·.,-,"/•",,'"" ,-.. ,,} ·-·!i<"'\-·,,ii:;.:'A.>:5•,j,;/ ,_. ;,.·'-I•,',">,-~·",i,", a_,-.. -~-,,·,;· ;, .. ,, L ·,:.,.•·c.;_,·,,-,·-0w.:·;~,'~,'•·'~,,,,"...;_c•_ ·,:~;;--,'<'.;-;."""-~·'· -,o,·-·cc-~, ·''Ve"-, .. ,~·_,, '.!.e£..::;:.' G!f.JeRALdt ./,< .. [;· JJa. '. = ~ Backfill & Compaction-embankment GI -1 $ 5.62 Backfill & Compaction-trench GI -2 $ 8.53 Clear/Remove Brush, by hand GI -3 $ 0.36 Clearing/Grubbing/Tree Removal GI -4 $ 8,876.16 Excavation -bulk Gl-5 $ 1.50 Excavation -Trench GI -6 $ 4.06 Fencing, cedar, 6' high GI -7 $ 18.55 Fencinc, chain link, vinyl coated, 6' hiah GI -8 $ 13.44 Fencina, chain link, aate, vln1wl coated, 2 GI -9 $ 1,271.81 Fencing, split rail, 3' high GI -10 $ 12.12 Fill & compact -common barrow GI -11 $ 22.57 Fill & compact -gravel base GI -12 $ 25.48 Fill & compact -screened topsoil GI -13 $ 37.85 Gabion, 12" deep, stone filled mesh GI -14 $ 54.31 Gabion, 18" deep, stone filled mesh GI -15 $ 74.85 Gabion, 36" deep, stone filled mesh GI -16 $ 132.48 Gradin~, fine, by hand GI -17 $ 2.02 !Grading, fine, with arader GI -18 $ 0.95 1Monuments, 3' long GI -19 $ 135.13 Sensitive Areas Sign GI -20 $ 2.88 Sodding, 1" deeo. slooed around GI -21 $ 7.46 Surveying, line & grade GI -22 $ 788.26 Survevini:i, lot location/lines GI -23 $ 1,556.64 Traffic control crew ( 2 flagaers) GI -24 $ 85.18 Trail. 4" chipped wood GI -25 $ 7.59 Trail, 4" crushed cinder GI -26 $ 8.33 Trail, 4" top course GI -27 $ 8.19 Wall, retaining, concrete GI -28 $ 44.16 !Wall, rockery GI -29 $ 9.49 Page 3 of 9 SUBTOTAL *KCC 27A authorizes only one bond reduction Renton BOND QUANTITY WORKSHEET 2011-06-06.xlsx ,.·,:,:, _,_.,: -· CY CY SY Acre CY CY LF LF Each LF CY CY CY SY SY SY SY SY Each Each SY Day Acre HR SY SY SY SF SF -'.lli~i~!it '. ,; '/.-/ r:/i-,l'!:l!!J~ liil~lla , __ \ _ --. :" · .1~r1Viii§, ~tg!lwi#.Way , • < , .1e,i/iaflfll,1<l,~11riu c: ,'.•, ,-iAi• rtJ~lil,1 ' 1(h;~;f"~ii~(;;~~.~~j ~~~=: ~.~1:j=~ii~1·;~;~ ,;f ~[~f~i~':~' ;-~~~~ , .. Cost 400 4840 900 310 2 270.26 270.26 Check out the DDES Web site 2,248.00 1/42.40 1,350.00 4,166.40 1,271.81 10,778.61 Unit prices updated: 02112102 Version: 4122102 Report Date 513/2013 ~1te Improvement 8ond Quantity VVorKsheet .•.[fj;f'i;'tf !.I·., • ·_.•. •· • g / •-I >i•_· ; I .. / ·-.. _:,_._.•_• {_itl~~~ri,~{'. .i _ _ +Jl/l~ttl!l@i!fi(·• ·· ···· r;)~riy~i~c{{ •_:.i:_• _.· . . Btihd Redu. cti<ln'. .. _._ . · . _ ,;•<. ·. •· < 'j;, > 1<' :~1jjli1.'/11,11ia1 l'lil&lfJml!id)limi!61s . . . tt()prilv'i!iir~li< · · .. · ... . ·.·. · .. :·.·.·····' . '. . ·.• ' i > .... • > I '·• < ;p< ···Unit '.,~u4~~,,;'.i~~t:i~1 < .•• tl:~r:~:~~:~:~~.·\,]i . Qusnt,J .,:: ·~ti~·n ..•... · d~~i1!te · ..... ~cisi . ltQAtl.1Mr11UlVEMElllf'_,>•••·'·'!Nili·• -• /:· . < \-·•· .. •:. ''<<•,.. ;·.·.·• • >-•· _._._•_. ._.: •:.+ • .·_ .. ··-.-_ AC Grinding, 4' wide machine < 1 OOOsy RI -1 $ 23.00 SY AC Grinding, 4' wide machine 1000-200 RI -2 $ 5.75 SY AC Grinding, 4' wide machine > 2000sy RI -3 $ 1.38 SY AC Removal/Disposal/Repair RI -4 $ 41.14 SY Barricade, type I RI -5 $ 30.03 LF Barricade, type Ill (Permanent) RI -6 $ 45.05 LF 20 901.00 Curb& Gutter, rolled RI -7 $ 13.27 LF Curb & Gutter, vertical RI -8 $ 9.69 LF 773 7,490.37 Curb and Gutter, demolition and disposal RI. 9 $ 13.58 LF Curb, extruded asphalt RI -10 $ 2.44 LF Curb, extruded concrete RI -11 $ 2.56 LF Sawcut, asphalt, 3" depth RI -12 $ 1.85 LF Sawcut, concrete, per 1" deoth RI -13 $ 1.69 LF Sealant, asphalt RI -14 $ 0.99 LF Shoulder, AC, ( see AC road unit price) Rl-15 $ SY Shoulder, gravel, 4" thick RI -16 $ 7.53 SY Sidewalk, 4" thick RI -17 $ 30.52 SY 294 8,972.88 Sidewalk, 4" thick, demolition and dispos RI -18 $ 27.73 SY Sidewalk, 5" thick RI -19 $ 34.94 SY Sidewalk, 5" thick, demolition and dispo~ RI -20 $ 34.65 SY Sign, handicap RI -21 $ 85.28 Each Striping, per stall RI -22 $ 5.82 Each Striping, thermoelastic, I for crosswalk) RI -23 $ 2.38 SF Striping, 4" reneclor"'ed line RI -24 $ 0.25 LF Page4of9 SUBTOTAL 17,364.25 *KCC 27A authorizes only one bond reduction Renton BOND QUANTITY WORKSHEET 2011-06-06.xlsx Check out the DDES Web site Unit prices updated• 02112102 Version• 4122102 Report Date: 51312013 ;::,1te Improvement l:jOna Quantity vv'orKsheet .... ) ,.}i~~J.~f~~t1~1ill1 :~1i;~l1t1~tl!ti~t ~:1itfy:.~~E!tl~:;! i\QU\!lll\. ''i< ,.,;~§.t;;c,·::;i "· ijfni;:,: ,,,;'):.·.;;~tk&Ci'.i/i;;!i~n!;i1% ''.:Jt;;.,,~$~f C.ost ~oAb:tiJRFAGIINll•?jil'i'!,t/i/bk ~lslla~i!$ i.su !otle.i\i~J'\~l/f '~:iKcM<!i~'ili<>ll~"'.~\W/i~.~,t;g;.i~~piiu~ff . · ·. ··.-:. : .i For KCRS '93, (additional 2.5" base) addj RS -1 I $ 3.60 I SY AC overlay. 1.5" AC I RS -21 $ AC Overlay. 2" AC RS -31 $ AC Road,_2", 4"roc_k, First 2500 SY RS -41 $ AC Road, 2", 4" rock. Qty. over 2500SY I RS -51 $ AC Road, 3", 4" rock, First 2500 SY I RS -61 $ AC Road, 3", 4" rock, Qty. over 2500 SY I RS -71 $ AC Road,_§", First 2500 SY I RS -8J $ AC Road, 5", Qty. Over 2500 SY RS-91 $ AC Road~ First 2500 SY IRS-1~ $ AC Road, 6", Qty. Over 2500 SY IRS -111 $ Asphalt Treated Base, 4" thick '1S -1 ~ $ Gravel Road,_j" rock, First 2500 SY "S -q $ Gravel Road, 4" rock, Qty. over 2500 SY IRS -14 $ PCC Road2'_, no base, over 2500 SY ~S -1 ~ $ PCC Road, 6'', no base, over 2500 SY IRS -1~ $ Thickened Ed.11_e IRS -1Jj $ 7.39 8.75 17.24 13.36 19.69 15.81 14.57 13.94 16.76 16.12 9.21 11.41 7.53 21.51 21.87 6.89 Page 5 of 9 SUBTOTAL "'KCC 27A authorizes only one bond reduction. Renton BOND QUANTITY WORKSHEET 2011-06-06.xlsx SY SY SY SY SY I ' SY SY SY SY SY SY SY SY SY SY LF r I 8021 15,791.38 ' 15,791.38 Check out the DDES Web site Uni1 prices updated, 02/12/02 Version: 4/22/02 Report Date, 513/2013 Site Improvement ~ond Quantity Worksheet .: cc.:.\y:. ; ··· \ ::{>,· ·· . v,,.. y/i'"·"·i"'I · c:,, ,.: t,.,,;!;;; .• .. , . ii tx:,,,, .. ,,, , ·,>, .. , .111«>,,,,:·.ci/'·. ,.•. .· l)ttd .. ut 10 •· . '}}} jfiifg,(:\· ;~;,,~·1C; .·.. . ) . , '··11~11 ~~!!QlJ~ ······•·· •·· . ~if . ' ii S R~d I h . dMIHA!iiEi ;qzp~~'!;tlf/Ggati\li ~r~~t~i'!i>tNJtir ~t\~jys]~pt)·. ··.;.·. :·. ;;~;H'fo)ii/1'1 t~: Avifiiiu~Bi¥~.t~fii~ii1i@t Alili•~~tii!H'il@i.\a'.~1i~(i\\ketili~ & ii.iia ~Ip), .· ...• , • . Access Road, RID D -1 $ 16.74 Bollards -fixed D-2 $ 240.74 Bollards . removable D-3 $ 452.34 * {CBs Include frame and lid) CB Type I D-4 $ 1,257.64 CB Tv= IL D-5 $ 1,433.59 CB Type II, 48·' diameter D-6 $ 2,033.57 for additional deoth over 4' D-7 $ 436.52 CB Tvpe II, 54" diameter D-8 $ 2,192.54 for additional depth over 4' D-9 $ 486.53 CB Type II, 60" diameter D -10 $ 2,351.52 for additional depth over 4' D-11 $ 536.54 CB Type II, 72" diameter D -12 $ 3,212.64 for additional depth over 4' D -13 $ 692.21 Through-curb Inlet Framework (Add) D -14 $ 366.09 Cleanout, PVC, 4" D -15 $ 130.55 Cleanout, PVC, 6' D -16 $ 174.90 Cleanout, PVC, 8" D-17 $ 224.19 Culvert, PVC, 4" D-18 $ 8.64 Culvert, PVC, 6" D -19 $ 12.60 Culvert, PVC, 8" D -20 $ 13.33 Culvert, PVC, 12" D -21 $ 21.77 Culvert, CMP, 8" D -22 $ 17.25 Culvert, CMP, 12" D -23 $ 26.45 Culvert, CMP, 15" D -24 $ 32.73 Culvert, CMP, 18" D -25 $ 37.74 Culvert, CMP, 24" D-26 $ 53.33 Culvert, CMP, 30" D-27 $ 71.45 Culvert, CMP, 36" D -28 $ 112.11 Culvert, CMP, 48" D -29 $ 140.83 Culvert, CMP, 60" D -30 $ 235.45 Culvert, CMP, 72" D -31 $ 302.58 Page 6 of 9 SUBTOTAL ~Kee 27A authorizes only one bond reduction. Renton BOND QUANTITY WORKSHEET 2011-06-06.xlsx SY Each Each Each Each Each FT Each FT Each FT Each FT Each Each Each Each LF LF LF LF LF LF LF LF LF LF LF LF LF LF Check out the DDES Web site 67 3 6 2 4 1 6 1,121.58 1,357.02 7.545.84 4,067.14 1,746.08 2,192.54 2,919.18 20,949.38 Unit prices updated: 02/12/02 Version: 4/22/02 Report Date: 5/3/2013 ::;,te Improvement Bond Quantity Worksheet Culvert, Concrete, 8" D -32 $ 21.02 LF Culvert, Concrete, 12" D -33 $ 30.05 LF Culvert, Concrete, 15" D -34 $ 37.34 LF Culvert, Concrete, 18" D -35 $ 44.51 LF Culvert, Concrete, 24" D -36 $ 61.07 LF Culvert, Concrete, 30" D -37 $ 104.18 LF Culvert, Concrete, 36" D -38 $ 137.63 LF Culvert, Concrete, 42" D -39 $ 158.42 LF Culvert, Concrete, 48" D -40 $ 175.94 LF Culvert, CPP, 6" D -41 $ 10.70 LF Culvert, CPP, 8" D -42 $ 16.10 LF Culvert, CPP, 12" D -43 $ 20.70 LF Culvert, CPP, 15" D -44 $ 23.00 LF Culvert, CPP, 18" D -45 $ 27.80 LF Culvert, CPP, 24" D -48 $ 36.80 LF Culvert, CPP, 30" D -47 $ 48.30 LF Culvert, CP P, 36" D -48 $ 55.20 LF Ditchini:i D -49 $ 8.08 CY Flow Disoersal Trench (1,436 base+\ D -50 $ 25.99 LF French Drain (3' depth) D -51 $ 22.80 LF Geotextile, laid in trench, polypropylene D -52 $ 2.40 SY Infiltration pond testing D -53 $ 74.75 HR Mid-tank Access Riser, 48" dia, 6' deep D -54 $ 1,805.40 Each Pond Overflow Spillway D -55 $ 14.01 SY Restrictor/Oil Separator, 12'' D -56 $ 1,045.19 Each Restrictor/Oil Separator, 15" D -57 $ 1,095.56 Each Restrictor/011 Separator, 18" D -58 $ 1,148.16 Each Riprap, placed D -59 $ 39.08 CY Tank End Reducer (36" diameter) D -60 $ 1,000.50 Each Trash Rack, 12'' D-61 $ 211.97 Each Trash Rack, 15" D -62 $ 237.27 Each Trash Rack, 18" D -63 $ 268.89 Each Trash Rack, 21" D -64 $ 306.84 Each Page 7 of 9 SUBTOTAL *KCC 27A authorizes only one bond reduction. Renton BOND QUANTITY WORKSHEET 2011-06-06.xlsx ·;,!.,t~~:~~~iif \i:i;ti ~;~llliE:~·~-,j ;·)/: .· .. ; ...... . ·:~o~iiL ·· ... ii\~ ),;;:i?:; ;;;ifuJfil?\ 'b,,;,I'Qt\s1:J. , '· ; .J}ihl~nt;:; ;;.· ) l::0$!, . cost 398 Check out the DDES Web site 8238.6 1045.19 9283.79 Unit prices updated; 02/12/02 Version: 4/22/02 Report Date; 5/3/2013 ~lte Improvement 8ond Quantity vVorKsheet No. 2" AC, 2" top course rock & 4" borrow PL-1 $ 15.84 SY 2" AC, 1.5" top course & 2.5" base cour PL-2 $ 17.24 SY 4" select borrow PL-3 $ 4.55 SY 1.5" to.e_ course rock & 2.5" base course PL-4 $ 1141 SY Wl-t $ 1,200.00 Each I I I I 1 Wl-2 SY Wl-3 CY Wl-4 LF Wl-5 FT Wl-6 Wl-7 Wl-8 Wl-9 Wl-10 SUBTOTAL SUBTOTAL (SUM ALL PAGES): 33,425.89 30% CONTINGENCY & MOBILIZATION: 10,027.77 GRANDTOTAL: 43,453.66 COLUMN: B C Page 8 of 9 *KCC 27A authorizes only one bond reduction. Renton BOND QUANTITY WORKSHEET 2011-06-06.xlsx Check our the DDES Web site Iii.pod ~eduction' - Cost 1,200.00 1,200.00 42,211.78 12,663.53 54,875.31 D E Unit prices updated: 02/12/02 Version 4/22/02 Report Date 5/3/2013 Site Improvement Bond Quantity Worksheet Orlglnal bond computations prepared by: Name: Hal Hagenson, Date: 513/2013 PE Registration Number: 21283 Tel.#: 206-938-6168 Finn Name: Hagenson Consultants, LLC Address: 6484-48th Ave SW, Seattle, WA 98136 Project No: 201210 ROAD IMPROVEMENTS & DRAINAGE FACILITIES FINANCIAL GUARANTEE REQUIREMENTS Stabilization/Erosion Sediment Control (ESC) Existing Right-of-Way Improvements (A) (BJ Future Public Road Improvements & Drainage Facilities (C) Private Improvements (D) Calculated Quantity Completed $ $ $ $ PERFORMANCE BOND• AMOUNT 8,935.3 43,453.7 54,875.3 Total Right-of Way and/or Site Restoration Bond*/"'"' (First $7,500 of bond• shall be cash.) (A+B) $ 8,935.3 Performance Bond* Amount (A+B+C+D) = TOTAL (T) $ 107,264.2 Mm1mum bond* amount 1s $1000. Reduced Performance Bond* Total *** Maintenance/Defect Bond• Total NAME OF PERSON PREPARING BOND" REDUCTION: BOND.AMOUNT REQUIRED AT RECORDING OR TEMPORARY OCCUPANCY ••• (E) $ Tx0.30 $ 32,179.3 OR (T-E) $ 107,264.2 Use larger of Tx30% Or' (T-E) Date: '" NOTE: The word "bond" as used in this document means any financial guarantee acceptable to King County. ""'NOTE: KCC 27A authorizes right of way and site restoration bonds to be combined when both are required. PUBLIC ROAD & DRAINAGE MAINTENANCE/DEFECT BOND• (B+C) x 0.25 = $ 10,863.4 The restoration requirement shall include the total cost for all TESC as a minim11m, not a maximum. In addition, corrective work, both on-and off-site needs to be included. Quantities shall reflect worse case scenarios not just minimum requirements. For example, if a salmonid stream may be damaged, some estimated costs for restoration needs to be reflected in this amount. The 30% contingency and mobilization costs are computed in this quantity . ....... NOTE: Per KCC 27A, total bond amounts remaining after reduction shall not be less than 30% of the original amount (T) or as revised by major design changes. SURETY BOND RIDER NOTE: If a bond rider is used, minimum addttional performance bond shall be j $ 98,329.0 !(C+D)-E REQUIRED BOND· AMOUNTS ARE SUBJECT TO REVIEW AND MODIFICATION BY DDES Page 9 o/9 Renton BOND QUANTITY WORKSHEET 2011-06-06.xlsx Check out the DDES Web site Unit prices updated: 02/12/02 Version: 4/22102 Report Date: 5/312013 KfNG COUNTY. WASHINGTON. SURFACE WATER DESIGN MANUAL STORMWATER FACILITY SUMMARY SHEET DDES Permit Number -~------(provide one Storrnwater Facility Summary Sheet per Natural Discharge Location) Overview: Project Name L AJcEs I DE J:'A.1 rcw DW T IA"T Date ---------------------------------- Downstream Drainage Basins Major Basin Name BLAClc l2..i.1eiL Immediate Basin Name PAIJ1HElL CR.FFK Flow Control: Flow Control Facility Name/Number--------------- Facility Location. ___ i_i_e,,_1._1_-__ 11_t._""_"_A._v_E_· _s_:::-__________________ _ If none, Flow control provided in regional/shared facility (give location) _______________ _ No flow control required Exemption number General Facility Information: Type/Number of detention facilities: Type/Number of infiltration facilities: I ponds ponds vaults tanks --- ---tanks trenches ControlStructureLocation AT 5 \N C DfUJ Er, [! f P D11D 1f'c.A-CT Type of Control Structure _c_o_u_T_t_oL_M_H_. ·_1_'1_rr._1I._· _S-_4_' ___ Number of Orifices/Restrictions ,, - Size of Orifice/Restriction: No. I 1/L 11 No. 2 I 11 N 3 -~7=/-B-,,---- o. ------- No. 4 ------- Flow Control Performance Standard Uc \/E:l 11.. C DI.Is F_V 4 T! c'u t-:..ru.1 2005 Surface Water Design Manual J/1/05 1 KING COUNTY. WASHINGTON, SURFACE WATER DESIGN MANUAL Live Storage Volume __ ~_1 ,_7_'l_l_r_i::" ___ Depth __ S-_. 7_Yi_1 ___ Volume Factor of Safety -& Number of Acres Served I , 4 ---------- Number of Lots B ---------- Dam Safety Regulations (Washington State Department of Ecology) Reservoir Volume above natural grade ___ -&~---- Depth of Reservoir above natural grade------- Facility Summary Sheet Sketch All detention, infiltration and water quality facilities must include a detailed sketch. ( l l "x l 7" reduced size plan sheets may be used) 111/05 2005 Surface Water Design Manual 2 R/D FACITIL Y SKETCH 5-1-13 CB # TYPE II TE 490"°'.0a----, IE 481.60 EMERGENCY OVERFLOW TYPE II CB W / BIRDCAGE ) ,\, TE: 487.52 Ii=' \\ SHED ' J.ji\:i i .. ,'.i 1 '.;J"! . •,' '_, ' ,, . ~\ 1 t n.-: [ 6' BLACK VlNYL COATED CHAIN LINK FENCE -------- ~ --' \ ) ' 26'-1~% ~ ----~~~::~:~--~-----------!-~II ~ WJ LOT6 EASEME~~ ~ 1 ' ; -~ ..... ~-,,_ I LOT? ~: ~"<.· I, 4512 SF " -~ CONTROL.MH ~!!:!!!!:!!!~~:::::::::::::::::: _____ ===: ~\, TYPE 1154" RIM: 490.0 .1 '-'- OUTLET: 481.70 I ____ _ SEE DETAIL GATE I -:_~111/1: 4513 'SF WET /DETENTl<iN POND WETPOND 47/1.5 TO 481.7 VOL REQD J 4039 CF VOL PROVl0ED = 4179 DETENTION' 481.7 TO 487.4 VOL REOf/PROVIDED = 17,7 I 0 '40 ' -117 --:...--,-"'" I I / L 1 ihCh • \ .. ------±o=n~~a::--------------1----, I . . 'TU· . tt. • .., ; r ll. ~· ,,,., ·';-~- , .. / ,.,, ' I --' \ • I .. c-;,·· • \ • "' •. \....,_4_90" "-.. . .. -· . ., . ., 4 · • .,. • . f .. ·. 11· ~. I:~~ " >-'---, n l" ' . ... 1 ·· l~ -~'! r--. ··•·· .. . ' .. • -ca-I --, L.., i' / -:CJ. ....,.... }AJ I! \A/ (if 11 yy I --~-~. -~t -~-~-~--+--~-~-~ 1 2+00 MH I r-- ! -4. . ., -,- 'Tl'• ••• -. -·-• I ·-·--· ~ ,---:r -• ·I .,.--.. ·,-_I''~ ~:.:.._ ·1. 1· · ____ • __ • .f • .,, ., . .., ·. "'I .4· ~-· · • ., · -~ T -,- KING COUNTY. WASHINGTON. SURFACE WATER DESIGN MANUAL Water Quality: Type/Number of water quality facilities/BMPs: biofiltration swale large) above --- ( regular/wet/ or continuous inflow) large) I combined detention/wetpond --- --- ( wetpond portion basic or large) combined detention/wetvault filter strip ___ flow dispersion ___ farm management plan ___ landscape management plan ___ oil/water separator (baffle or coalescing plate) Liner9 _________ _ catch basin inserts: ---Manufacturer ___ sand filter (basic or large) sand filter, linear (basic or --- ___ sand filter vault (basic or sand bed depth. ___ (inches) stonnwater wetland --- storm filter --- ___ wetpond (basic or large) wetvault --- NO Is facility Lined? If so, what marker is used --------------------- ---pre-settling pond ___ pre-settling structure: Manufacturer ___________________ _ ___ high flow bypass structure (e.g., flow-splitter catch basin) source controls --- Design Information Water Quality design flow -------------- Water Quality treated volume (sandfilter) --------- Water Quality storage volume (wetpool) 4D3'l fl....E-1;>[ 417 q ff'O!! iLZ:, Facility Summary Sheet Sketch 2005 Surface Water Design Manual 1/1/05 KTNG COUNTY. WASHINGTON. SURFACE WATER DESIGN MANUAL All detention, infiltration and water quality facilities must include a detailed sketch. (11 "xi 7" reduced size plan sheets may be used) T/1/05 2005 Surfuce Water Design Manual Completed by: Pollution Prevention Team Trtle: Date: Responsible Official: Title: Team Leader. Office Phone: Cell Phone #: Pager#: Responsibilities: (1) Title: Office Phone: Pager#: Cell Phone: Responsibilities: ' (2) Title: Office Phone: Pager#: ' Cell Phone #: Responsibilities: 2005 Surface Water Design Manual (CSWPP Fonns) 1/24/2005 Page 1 MAINTENANCE AND DEFECT AGREEMENT (Two Years) Applicant's Name and Address For public roads and drainage lacftilies Agreement Number Project Number and Name Guarantee Amount Sile Location/Section This AGREEMENT is made and entered into this day of 19 ~ between the City of Renton. hereinafter called the CITY, and the above named APPLICANT, hereinafter called APPLICANT. Basis tor AGREEMENT: WHEREAS the undersigned APPLICANT has constructed public roads and/or drainage facilities in connection with the above-referenced project: and WHEREAS the APPLICANT has agreed to secure the successful maintenance and operation of said improvements for the referenced projects pursuant to RMC 4-6--030 NOW THEREFORE, the APPLICANT hereby agrees and binds itself and its legal representatives, successors, and assigns as follows: Terms of the AGREEMENT: I. The improvements constructed by the APPLICANT or his representative shall successfully operate and shall remain free of defects in design, workmanship, materials, and design for a period of two years from the date of satisfactory completion of the improvements or finai piat approval, whichever is later. As used in this AGREEMENT, the term "defects" includes but is not limited to, damage resulting from construction activities and/or use during the two year period. 2. The APPLICANT is responsible for maintenance of the public road and drainage facilities. including the roadway surface for the two year period from the date of satisfactory construction approval or final plat approval, whichever is later. 3. In the event of any failure of the improvements to satisfactorily operate or in the event of a defect in design, workmanship or materials, the APPLICANT shall promptly and adequately repair and/or correct the failure or defect. 4. The CITY will perform maintenance inspections during fhe two year period. 5. During the two year period upon notification by the CITY, the APPLICANT shall correct and/or make repairs to the right-of-way improvements within the time period specified by the CITY when defects in the design. workmanship, or materials occur. 6. In the event the CITY determines that repairs must be performed immediately to prevent risk to person(s) and property, the CITY may make necessary repairs and the costs of those repairs shall be paid by the APPLICANT upon demand. 7. The APPLICANT shall pay all required fees in accordance with Renton Municipal Code. 8. Af the end of the two year period, the APPLICANT shall clean the drainage system prior to the CITY's final inspection. P!112 Agreement Number Project Number and Name 9. If, at the conclusion of the two year period, the City of Renton, at its sole discretion, determines that the improvements are not adequately maintained, the APPLICANT shall perform prompt maintenance to the CITY's satisfaction. In the event this maintenance is not performed within the time period specified by the CITY, the CITY will invoke the enforcement processes found in RMC 1-3. I 0. Any failure by the APPLICANT to comply with the terms of this AGREEMENT in a timely manner shall constitute default. Any action or inaction by the City of Renton following any default in any term or condition of this AGREEMENT shall not be deemed to waive any rights of the City of Renton pursuant to this AGREEMENT. 11. The APPLICANT shall indemnify and hold the CITY and its agents, employees and/or officers harmless from and shall process and defend at its own expense all claims, damages, suits at law or equity, actions, penalties, losses, or costs of whatsoever kind or nature, brought against the CITY arising out of, in connection with, or incident to the execution of this AGREEMENT and/or the APPLICANT's performance or failure to perform any aspect of the AGREEMENT. Provided, however, that if such claims ore caused by or result from concurrent negligence of the APPLICANT and the CITY, its agents, employees and/or officers, this provision shall be valid and enforceable only to the extent of the negligence of the APPLICANT, and provided further, that nothing herein shall require the APPLICANT to hold harmless or defend the CITY from any claim arising from the sole negligence of the CITY's agents, employees and/or officers. 12. In the event that any parfy deems it necessary to institute legal action or proceedings to enforce any right or obligation under this AGREEMENT, the parties hereto agree that any such action or proceeding shall be brought in a court of competent jurisdiction situated in King County, Washington. Release Requirements: This AGREEMENT shall remain in full force and effect and shall not be released until all terms of this AGREEMENT have been completed to the satisfaction of the City of Renton. IN WITNESS THEREOF, the parties hereto have executed this AGREEMENT as of the day and year first above written. APPLICANT By TIiie Date Received for City of Renton By Dote 116/2010 RECORDING REQUESTED BY AND WHEN RECORDED MAIL TO: CITY CLERK'S OFFICE CITY OR RENTON 1055 SOUTH GRADY WAY RENTON WA 98057 DECLARATION OF COVENANT FOR INSPECTION AND MAINTENANCE OF STORMWATER FACILITIES AND BMPS Grantor: -------------- Grantee: City or Renton Legal Description:--------------------------- Additional Legal(s) on:------------------------- Assessor's Tax Parcel ID#:------------------------ IN CONSIDERATION of the approved City or Renton permit for application file No. LUA/SWP relating to the real property ("Property") described above, the Grant or( s ), the owner( s) in fee of that Property, hereby covenants( covenant) with the City or Renton, a political subdivision of the state of Washington, that he/she(they) will observe, consent to, and abide by the conditions and obligations set forth and described in Paragraphs 1 through 10 below with regard to the Property, and hereby grants(grant) an easement as described in Paragraphs 2 and 3. Grantor(s) hereby grants(grant), covenants(covenant), and agrees(agree) as follows: 1. The Grantor(s) or his/her(their) successors in interest and assigns ("Owners") shall at their own cost, operate, maintain, and keep in good repair, the Property's stormwater facilities and best management practices ("BMPs") identified in the plans and specifications submitted to King County for the review and approval of permit(s) #: . Stormwater facilities include pipes, swales, tanks, vaults, ponds, and other engineered structures designed to manage stormwater on the Property. Stormwater BMPs include dispersion and infiltration devices, native vegetated areas, permeable pavements, vegetated roofs, rainwater harvesting systems, reduced impervious surface coverage, and other measures designed to reduce the amount of stormwater runoff on the Property. 2. City or Renton shall have the right to ingress and egress over those portions of the Property necessary to perform inspections of the storm water facilities and BMPs and conduct other activities specified in this Declaration of Covenant and in accordance with RMS 4-6-030. This right of ingress and egress, right to inspect, and right to perform required maintenance or repair as provided for in Section 3 below, shall not extend over those portions of the Property shown in Exhibit "A." 3. If City of Renton determines that maintenance or repair work is required to be done to any of the stormwater facilities or BMPs, City of Renton shall give notice of the specific maintenance and/or repair work required pursuant to RMC 4-6-030. The City shall also set a reasonable time in which such work is to be completed by the Owners. If the above required maintenance or repair is not completed within the time set by the City, the City may perform the required maintenance or repair, and hereby is given access to the Property, subject to the exclusion in Paragraph 2 above, for such purposes. Written notice will be sent to the Owners stating the City's intention to perform such work. This work will not commence until at least seven (7) days after such notice is mailed. If, within the sole discretion of the City, there exists an imminent or present danger, the seven (7) day notice period will be waived and maintenance and/or repair work will begin immediately. 4. !fat any time the City of Renton reasonably determines that a stormwater facility or BMP on the Property creates any of the hazardous conditions listed in KCC 9.04.130 or relevant municipal successor's codes as applicable and herein incorporated by reference, The City may take measures specified therein. 5. The Owners shall assume all responsibility for the cost of any maintenance or repair work completed by the City as described in Paragraph 3 or any measures taken by the County to address hazardous conditions as described in Paragraph 4. Such responsibility shall include reimbursement to the County within thirty (30) days of the receipt of the invoice for any such work performed. Overdue payments will require payment of interest at the current legal rate as liquidated damages. If legal action ensues, the prevailing party is entitled to costs or fees. 6. The Owners are hereby required to obtain written approval from City of Renton prior to filling, piping, cutting, or removing vegetation ( except in routine landscape maintenance) in open vegetated stormwater facilities (such as swales, channels, ditches, ponds, etc.), or performing any alterations or modifications to the stormwater facilities and BMPs referenced in this Declaration of Covenant. 7. Any notice or consent required to be given or otherwise provided for by the provisions of this Agreement shall be effective upon personal delivery, or three (3) days after mailing by Certified Mail, return receipt requested. 8. With regard to the matters addressed herein, this agreement constitutes the entire agreement between the parties, and supersedes all prior discussions, negotiations, and all agreements whatsoever whether oral or written. 9. This Declaration of Covenant is intended to protect the value and desirability of the real property described above, and shall inure to the benefit ofall the citizens of the City of Renton and its successors and assigns. This Declaration of Covenant shall run with the land and be binding upon Grantor(s), and Grantor's(s') successors in interest, and assigns. 3 10. This Declaration of Covenant may be terminated by execution ofa written agreement by the Owners and the City that is recorded by King County in its real property records.IN WITNESS WHEREOF, this Declaration of Covenant for the Inspection and Maintenance of Storm water Facilities and BMPs is executed this __ day of _________ , 20 __ GRANTOR, owner of the Property GRANTOR, owner of the Property STATE OF WASHINGTON ) COUNTY OF KING )ss. On this day personally appeared before me: ------------------'tome known to be the individual(s) described in and who executed the within and foregoing instrument and acknowledged that they signed the same as their free and voluntary act and deed, for the uses and purposes therein stated. Given under my hand and official seal this __ day of _________ , 20 __ Printed name Notary Public in and for the State of Washington, residing at My appointment expires---------- Return Address: City Clerk's Office City of Renton 1055 South Grady Way Renton, WA 98057 Title: DRAINAGE EASEMENT Project File #: Property Tax Parcel Number: Street Intersection or Project Name: Reference Number(s) of Documents assigned or released: Additional reference numbers are on page __ . Grantor(s): Grantee(s): 1. 1. City of Renton, a Municipal Corporation Additional legal is on page __ of document. (Abbreviated legal description MUST go here.) LEGAL DESCRIPTION: That said Grantor(s), for and in consideration of mutual benefits, do by these presents, grant, bargain, sell, convey, and warrants unto the said Grantee, its successors and assigns, an easement for drainage with necessary appurtenances over, under, through, across and upon the following described property (the right- of-way) in King County, Washington, more particularly described above. For the purpose of constructing1 reconstructing, installing, repairing, replacing, enlarging, operating and maintaining storm drainage lines and manholes, together with the right of ingress and egress thereto without prior institution of any suit or proceedings of law and without incurring any legal obligation or liability therefor. Following the initial construction of its facilities, Grantee may from time to time construct such additional facilities as it may require. This easement is granted subject to the following terms and conditions: 1. The Grantee shall1 upon completion of any work within the property covered by the easement, restore the surface of the easement, and any private improvements disturbed or destroyed during execution of the work, as nearly as practicable to the condition they were in immediately before commencement of the work or entry by the Grantee. 2. Granter shall retain the right to use the surface of the easement as long as such use does not interfere with the easement rights granted to the Grantee. Granter shall not, however, have the right to: a. Erect or maintain any buildings or structures within the easement; or b. Plant trees, shrubs or vegetation having deep root patterns which may cause damage to or interfere with the drainage facilities to be placed within the easement by the Grantee; or c. Develop, landscape, or beautify the easement area in any way which would unreasonably increase the costs to the Grantee of restoring the easement area and any private improvements therein. d. Dig, tunnel or perform other forms of construction activities on the property which would disturb the compaction or unearth Grantee's facilities on the right-of-way, or endanger the lateral support facilities. e. Blast within fifteen {15) feet of the right-of-way. f. Erect fences in such a way as to prevent access by the Grantee's vehicles to the Grantee's facilities. Any fence construction must provide for an opening {gated, removeable sections, barriers, etc.) of at least ten (10) feet in width. This easement shall run with the land described herein, and shall be binding upon the parties, their heirs, successors in interest and assigns. Granters covenant that they are the lawful owners of the above properties and that they have a good and lawful right to execute this agreement. By this conveyance, Grantor will warrant and defend the sale hereby made unto the Grantee against all and every person or persons, whomsoever, lawfully claiming or to claim the same. This conveyance shall bind the heirs, executors, administrators and assigns forever. IN WITNESS WHEREOF, I have hereunto set my hand and seal the day and year as written below. CORPORATE FORM DF ACKNOWI.EDGMENT Notary Seal must be within box STATE OF WASHINGTON ) ss COUN1Y OF KING ) On this ___ day of 20_, before me personally appeared to me known to be of the corporation that executed the within instrument, and acknowledge the said instrument to be the free and voluntary act and deed of said corporation, for the uses and purposes therein mentioned, and each on oath stated that he/she was authorized to execute said instrument and that the seal affixed is the corporate seal of said corporation. Notary Public in and for the State of Washington Notary (Print) My appointment expires: Dated: Exhibit A Legal Description Project: WO# PIO GRANTOR, Street: Map Exhibit X. MAINTENANCE AND OPERATIONS MANUAL KING COUNTY. WASHINGTON. SURF ACE WATER DESIGN MANUAL APPENDIX A MAINTENANCE REQUIREMENTS FOR FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES NO. 1 -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 Any 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 Seattle-King County Health Department Contaminants and Oil, gasoline, or other contaminants of one gallon No contaminants present other than Pollution or more, or any amount found that could: a surface film. (Coordination with 1} cause damage to plant, animal, or marine life; Seattle/King County Health 2) constitute a fire hazard; or 3) be flushed Department) downstream during rain stonns. Unmowed If facility is located in private residential area, When mowing is needed, Grass/Ground 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. policy is to make the pond site match adjacent Mowing of selected higher use areas ground cover and terrain as long as there is no rather 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 When 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 interferes with maintenance activity (i.e., slope be 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. 2005 Surface Water Design Manual -Appendix A t/24/2005 A-1 APPENDIX A MAINTENANCE REQUIREMENTS FLOW CONTROL CONVEYANCE. AND WQ F ACJLITIES NO. 1 -DETENTION PONDS Maintenance Defect or Problem Conditions When Maintenance Is Needed Results Expected When Component Maintenance Is Performed Side Slopes of Pond Erosion Eroded damage over 2 inches deep where cause Slopes should be stabilized by using of damage is still present or where there is appropriate erosion control potential for continued erosion. measure(s); e.g., rock Any erosion observed on a compacted berm reinforcement, planting of grass, embankment. compaction. lf 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 Liner is visible and has more than three 11.-inch Liner repaired or replaced. (If Applicable) holes in it. Pond Berms {Dikes) Settlement 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 Overtlow/Spillway blockage problems and may cause failure of the system is small (base less than 4 and Berms over 4 berm due to uncontrolled overtopping. inches) the root system may be left feet in height. Tree grmvth on benns over 4 feet in height may in place. Otherwise the roots should be removed and the berm restored. lead to piping through the bem, which could lead A licensed civil engineer should be to failure of the berm. consulted for proper berm/spillway restoration. Emergency Rock 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 top of out flow path of spillway. Rip-rap on inside slopes need not be replaced. 1/24/2005 2005 Surface Water Design Manual -Appendix A A-2 APPENDIX A MAINTENANCE REQUIREMENTS FOR FLOW CONTROL. CONVEYANCE. AND WQ F ACIL!TIES NO. 4-CONTROL STRUCTURE/FLOW RESTRICTOR Maintenance Defect or Problem Condition When Maintenance is Needed Results Expected When Component Maintenance is Perfonned General Trash and Debris Distance between debris build-up and bottom of AJI 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 ouliet pipe structure should support at and outlet pipe. least 1,000 lbs 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 waterti~t and Connections to outlet pipe are water show signs of rust. tight; structure repaired or replaced and works as designed. Any hole-er than designed holes-in the Structure has no hoJes other than structure. designed hrnes. 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 prope~y 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. worl<s as designed. Overt101.-v 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 See "Detention Tanks See "Detention Tanks and Vaults" Table No. 3 See "Detention Tanks and Vaults" and Vaults" Table No. 3 2005 Surface Water Design Manual -Appendix A 1/24/2005 A-5 APPENDIX A MAINTENANCE REQUIREMENTS FLOW CONTROL. CONVEYANCE. AND WQ F ACILffiES NO. 5-CATCH BASINS Maintenance Defect or Problem COnditions When Maintenance Is Needed Results Expected When Component Maintenance Is perfonned General Trash & Debris Trash or debris of more than Xr cubic foot whieh No Trash or debris located (lndudes Sediment) is located immediately in front of the catch basin immeclialely in front oi catch basin opening or is blocking capacity of the basin by opening. more than 10%. Trash or debris On the basin) that exceeds 1/, the No trash or debris in the catch deplt> from the bottom of basin lo Invert the basin. lowest pipe into or out of the basin. Trash or-in any Inlet or outlet pipe blocking Inlet and outlet pipes free of trash or more than 11, of its height. debris. Dead animals or vegetation that could generate No dead animals or vegetation odors that could cause complalnls or dangemus p,esent within the catch basin. gases (e.g., methane~ Deposits of gart>age exceeding 1 cubic fool in No condition praoent which -,kj volume. attract or support the breeding of insects or rodents. Structure Damage lo Comer of frame ""'8nds more than % inch past Frame is even with curt,_ Frame and/or Top curb face into the -(If applicable). Slab Top slab hes holes larger than 2 square inches Top slab Is free of holes and cracks. or aad<s wider than 14 inch ftntent i5 to make sure all material is ruming into basin). Frame not silting flush on lop slab, i.e., Frame is sitting flush on top slab. ~ of more than% inch of the frame from the lop slab. Cracks in Basin Cracks wider than 14 inch end longer then 3 -. Basin replaced or n,paired lo design Walls/Bollom any evidence of son particles entering c:at,;h 91andards. basin through cracks, ormainlenarn:e peison judges that s1ruc1ure is unsound. Cracks wider than ;,.; inch end longer then 1 foot No aacks more than 11. inch wide at at the joint of any inlet/outlet pipe or any the joint of inlel/oullel pipe. evidence of soil particles entering catch basin through cracks. Sel1lement/ Basin has -more than 1 inch or has rotated Besln replaced or repaired lo design Misaffgnment more than 2 inches out of alignment --Fire Hazan! Presence of chemicals such as natural gas, all No flammable chemicals -t. and gasoline. Vegetation V-1Bfi00 growing acrt!S$ end blocking more No vegetation bloc:king opmw,g to than 10% of the basin opening. basin. Vegelalion growing In inlet/outlet pipe joinls that No wgetallon or root growth is more than 6 Inches tall and less than 6 inches pn,sent. apart Pollution Nonflammable chemicals of more than 14 cubic No pd/ullon present -tt,an fool -three -of basin length. surfaco fflm. Catch Basin Cover Cover Not in Place Cover Is missing or only partially in plare. Arry Catch basin cover is - open catch basin requires maintenance. LDckingMechanism Mechanism cannot be opened by on Mechanism opens With proper IDOis. Nol Worl<ing mainlenance person with pn:rper tools. SoHs inlo frame have Jess than 14 inch oflhread. Cover Difficult lo One 1ll0linleralce per.ron cannot remove ffd after Cover can be removed by one Remove applying 80 lbs. of Ill!; intent ls keep~ from maintenance-· sealing off access lo mal11lenanc:e. Lad-Ladder Rungs Unsafe laddel' Is unsafe due to missing rungg, Ladder meets design slsndards and misalignment, rus~ mocks. or sharp edges. allows maintenance person safe access. ··-- 1/24/2005 2005 Suriace Water Design Manual -Appendix A A-6 APPENDIX A MAINTENANCE REQUIREMENTS FOR FLOW CONTROL. CONVEYANCE. AND WQ FACILITIES NO. 5 -CATCH BASINS Maintenance Defect or Problem Conditions When Maintenance is Needed Results Expected When ~--· Component Maintenance Is performed Melal Grates Unsafe Grate Grate with opening wider than 7 /8 inch. Grate opening meets design (If AppHcable) Opening standards. Trash and Debris Trash and debris that is blocking more than 20% Grate free of trash and dabris. of grate surface. Damaged or Missing. Grate missing or broken member(s) of the grate. Grate is in place and meets design standards. NO. 6-DEBRIS BARRIERS (E.G., TRASH RACKS) Malntanance Defect or Ptoblem Condition When llllalntenance is Needed Resulls Expaclad When Component Maintenance Is Perfonned. General Trash and Debris Trash or debris that is plugging more than 20% Barrier clear to receive capacity of the apermgs in the banier. flow. Metal Damaged/Missing Bars are bent out of shape more than 3 inches. Bars in p!ace with no bends more Bars. than% inch. Bars are missing or entire barrier missing. Bars in ptace according to design. Bars are loose and rust is causing 50% RepaiT or replace banier to design deterioration to any part of -· standards. ~--I NO. 7 -ENERGY DISSIPATERS Malrananca I 1>e1e<;t or P obtw,, I Cond!llons When Mamtanance Is -( Resulls E,._.i When . Component Maintenance is Performed. -= Rock Pad Missing or Moved Only one layer of rock exists above native soil in Replace rocks to design standerds. Rock aree five square -or larger, or any exposure of native soil. Dispersion Trench Pipe Plugged with AccumUlated sediment that exceeds 20% of the Pipe deaned/ftushed so that tt sediment design depth. matches~ Not Discharging V,sual evidance of water cfischarglng at Trench must be ~ed or Water Properly co,.:&11bated points along trench (normal rebuHt to Standards. condition is a "sheet flow'" of water along trench). Intent Is to prevent en:,sion ..._. Perto.allous Plugged. Over % of pe,forattons in pipe are plugged with Cl-, or replace pe,forated pipe. debris and sediment. Water Flows Qui Tap Maintenance person obsel""" -er flowing out Facfflly must be rebuilt or of "Oistribulor" catch duing any SIOm1 less than the design storm or ~tostandards. Basin. its causing or appears likely to cause damage. Receiving Alea Ove.--Water In receiving araa is causing or has No danger of-. Saturated potential of causing landsllde problems. Internal: Manhole/Chamber Worn or Damaged Struclw8 dissipating ffow delBllorates to % or Replace structure to design PosL Baffles, Side of origlnal size or arry concentraled WDm spot standards. Chamber exceeding one squara foot which would make structure unsoun:I. 2005 Suriilce Water Design Manual -Appendix A l/24/2005 A-7 APPENDIX A MAINTENANCE REQUIREMENTS FLOW CONTROL, CONVEYANCE. AND WQ FACILITIES NO. 8 -FENCING Maintenance Defect or Problem Conditions When Maintenance is Needed Results Expected When Component Maintenance is Performed General Missing or Broken Any defect in the fence that permits easy entry to Parts in place to provide adequate Parts a facility. security. Erosion Erosion more than 4 inches high and 12~ 18 No opening under the 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 Yi inches. 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. 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 more than 2% inches between posts. % inch sag between post. Extension arm missing, broken, or bent out of Extension arm in place with no shape more than 1% inches. bends larger than% inch. Deteriorated Paint or Part or parts that have a rusting or scaling Structurally adequate posts or parts Protective Coating condition that has affected structural adequacy. with a uniform protective coating. Openings in Fabric Openings in fabric are such that an 8-inch No openings in fabric. diameter ball could fit through. N0.9-GATES Maintenance Defect or Problem Conditions When Maintenance is Needed Results Expected When Component Maintenance is Performed General Damaged or Missing Missing gate or locking devices. Gates and Locking devices in place. Members Broken or missing hinges such that gate cannot Hinges intact and lubed. Gate is be easily opened and closed by a maintenance working freely. person. Gate is out of plumb more than 6 inches and Gate is aligned and vertical. more than 1 foot out of design alignment. Missing stretcher bar, stretcher bands, and ties. Stretcher bar, bands, and ties in place. Openings in Fabric See NFencing~ Table No. 8 See ~Fencing" Table No. 8 1/24/2005 A-8 2005 Surface Water Design Manual -Appendix A APPENDIX A MAINTENANCE REQUIREMENTS FOR FLOW CONTROL, CONVEYANCE. AND WQ F ACILIT!ES NO. 10-CONVEYANCE PIPES AND DITCHES Maintenance Defect or Problem Conditions When Malntenanc:e is Needed Results Expected When Component Maintenance Is Perfonned Pipes Sediment & Debris Accumulated sediment that exceeds 20% of the Pipe cleaned of all sediment and diameter of the pipe. debris. Vegetation Vegetation that reduces free movement of water All vegetation removed so water through pipes. flows keely through pipes. Damaged Protective coating is damaged; rust is causing Pipe repaired or replaced. more than 50% deterioration to any part of pipe. Any dent that decreases the cross section area Pipe repaired or replaced. of pipe by more than 20%. Open Ditches Trash & Debris Trash and debris exceeds 1 cubic foot per 1,000 Trash and debris cleared Imm square feet of ditch and slopes. ditches. Sediment Accumulated sediment that exceeds 20% of the Ditch cleaned/flushed of an design depth. sediment and debris so that It matches design. Vegetation Vegetativ11 that reduces free movement of water Water flows ~Y through ditches. through ditches. Erosion Damage to See "Detention Ponds .. Table No. 1 See "Detention Ponds" Table No. 1 Slopes Roel< Lining Out of Maintenance pe,son can see nathle soil beneath Replace rocks to design standards. Place or Missing (If the rock Hning. Applicable). NO. 11 -GROUNDS (LANDSCAPING) Maintenance Defect or P1oblen1 Conditions When Maintenance is Needed Results Expected When C omponern Maintenance is Performed General Weeds Weeds growing in more than 20% of the Weeds present in less than 5% of (Nonpoisonous. not landscaped area (treas and shrubs only). the landscaped area. noxious) Safety Hazard Any presence of poison ivy or other poisonous No poisonous vegetation ~t in veg-n. landscaped area. Trash or Utter Paper, cans, bottles, toteHng more than 1 cubic Area clear of litter. fool wilhin a landscaped area (trees and shrubs only) of 1,000 square feel Treas and Shrubs Damaged limbs or parts of treas or shrubs that are spilt or Trees and shrubs with lass than 5% broken -ch -.:t more than 25% of the total of totel foliage with split or broken foliage of the tree or shrub. imbs. Trees or shrubs tha1 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 adeqummy supported; remove any of the roots. dead or diseased trees. 2005 Surface Water Design Manual -Appendix A 1/24/2005 A-9 APPENDIX A MAINTENANCE REQUIREMENTS FLOW CONTROL, CONVEYANCE, AND WQ F AC!LITIES N0.12-ACCESS ROADS Maintenance Defect or Problem Condition When Maintenance is Needed Results Expected When Component Maintenance is Perlormed 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 Roadway free of debris which could or metal). damage tires. Any obstruction which reduces ciearance 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-foot 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, When any surface defect exceeds 6 inches in Road surlace 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. Modular Grid Build-up of sediment mildly contaminated with Removal of sediment and disposal Pavement petroleum hydrocarbons. in keeping with Health Department recommendations for mildly contaminated soils or catch basin sediments. Shoulders and Erosion Damage Erosion 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. 1/24/2005 2005 Surface Water Design Manual ~ Appendix A A-10 APPENDIX A MAINTENANCE REQUIREMENTS FOR FLOW CONTROL, CONVEYANCE. AND WQ FACILITIES NO. 16-WETPOND Maintenance Defect or Problem Condition When Maintenance is Needed Recommended Maintenance to Component Correct Problem Pond Area Water Level First cell empty, doesn't hold water. Line the first cell to maintain at least 4 feet of water. Although the second cell may drain, the first cell must remain full lo control turbulence of the incoming flow and reduce sediment resuspension. Defective Vegetation Vegetation such as grass and weeds need to be Vegetation should be mowed to 4 to mowed when it starts to impede aesthetics of 5 inches in height. Trees and pond. Mowing is generally required when height bushes should be removed where exceeds 18 inches. Mowed vegetation should be they are interfering with pond removed from areas where it could enter the maintenance activities; that is, at the pond. either when the pond level rises, or by inlet, outlet and near engineered rainfall runoff. structures. Algae Mats When algae mats develop over more than 10% Algae mats that cover more than of the water surtace, they should be removed. 10% of the surface of any cell Also remove mats in the late summer before fall should be removed. A rake or rains. especially in Sensitive Lake Protection mechanical device should be used Areas. Excessive algae mats interfere with to remove the algae. Removed dissolved oxygen content in the water and pose a algae can be left to dry on the pond threat to downstream ~kes if excess nutrients slope above the 100-year water are released. surface. Trash and Debris Accumulation that exceeds 1 cubic foot per 1000 Trash and debris removed from square foot of pond area. pond. Sediment Sediment accumulations in pond bottom that Removal of sediment from pond Accumulation exceeds the depth of sediment zone plus 6 bottom. inches, usually in the first cell. Oil Sheen on Water Prevalent and visible oil sheen. Remove oil from water by use of oil- absorbent pads or by vector truck. Refer probiem to ioc:ate source and correct. If chronic low levels of oil persist, pjant wetland plants such as Juncus effusus (soft rush) which can uptake small concentrations of oil. Erosion Erosion of the pond's side slopes and/or Slopes should be stabilized by using scouring of the pond bottom, that exceeds 6 proper erosion control measures, inches, or where continued erosion is prevalent. and repair methods. Pond Dike/Berm Settlement Any part of these components that has settled 4 Dike/berm is repaired to inches or lower than the design elevation, or specifications. inspector determines dike/berm is unsound. Internal Berm Concentrated Flow Berm dividing cells should be level. Build up low areas of berm or lower high areas so that the berm surface is level and water flows evenly over the entire length of the berm from the first cell to the second. lnleUOutlet Pipe Sediment and Debris Inlet/Outlet pipe clogged with sediment and/or No clogging or blockage in the inlet debris material. and outlet piping. Overflow Spillway Rock Missing Rock is missing and soil is exposed at top of Replace rocks to specifications. spillway or outside slope. 2005 Surface Water Design Manual~ Appendix A 1/24/2005 A-13 APPENDIX MAILBOX REQUIREMENTS NOTICE FOR ALL NEW PLATS AND SHORT PLATS City of Renton Planning Division 1055 South Grady Way-Renton, WA 98057 Phone: 425-430-7200 Fax: 425-430-7231 The Post Office wants to be involved in helping you locate your mailboxes before construction begins. Please call 1-800-275-8777 for the location of the Post Office that will service your plat. Then, take a copy of your plat map along with this form to the specified Post Office for their sign-off. Please submit the signed form along with your application. Property Location:18621 116th Ave SE Renton WA 98055 Owner's Name:~Y=vo=n=n=e~B=u~i ----------Phone Number: (206) 280-2272 Land Use Application Number:~LU,._A,_,0"'9._-.,_07,_,9.__ ______ --, Po,t()!f~-lc ~bare C:\Documents and Settings\Hal\My Documents\HC\Job Nos\HC\20121201210 Bui Renton\engineering\mailbox.doc -1 -08/07 LAKESIDE FAIRWOOO PLAT 5/21/1.3 I SHED I --i7I;:; ;;-2 5 DJS'II«: LIMNAIRE~ l I j .,..,. -.,., .. --~~-t BLDG ~VELOPE ------------w---C~13·~r ~I j 8 CJ Iii·: 30'~1-----00• I ' ' ~ jjli LOTT ' . I .J - 1 LOT 8 ih 4512 s,-'· ·1 I .,.,, "' - i I c.:'D L / ,_~!, -~m-1, • 1: 0 f S8..61)' I 1 inch .,,.,,,,...,, I I """ .0$ I STA. 1+94 -T 12. Lt / LOT 1 / 1--HYIJIANT . , 4618 SF" = 1~1 I_ 2-M!UST BL J~ LOT" 2 5' TC IIE '~· ,' : I ~ LOT 5 LO 4 ~ LOT 3 ~ 4508 SF" ~ii~i~:J:A A~ , 4534 SF° 4516 ·SF" I"' 4:514 Sf" IW\J ' o---f.1" I I I I I I I !! n,1 !•1 L__ _ 58,82' __l --~,·~·•,,,,_. __ _ :~ _ >&'3· _ / _ __ , ... ,. I ---~I 61.-46' _ jbj :1 f i- 1-12") 1-lHR GEOTECH CONSULTANTS, INC. lakeside Real Estate Investments 3520 South 198th Street SeaTac, Washington 98188 Attention: Michal Nguyen Subject: Clarification of Slope Regrading for Northwestern Lot (Lot 8) Proposed Short-Plat 18621 -116th Avenue Southeast Renton, Washington 13256 Northeast 20th Street, Suite 16 Bellevue, Washington 98005 (425) 747-5618 FAX (425) 747-8561 September 14, 2009 JN 09120 Reference: Geotechnical Engineering Study; same site; Geotech Consultants, Inc.; June 19, 2009. Dear Mr. Nguyen: via email This letter is intended to clarify our recommendations related to mitigation of any potential steep slope hazard presented to the planned residence for the northwestern lot (lot 8) of the short-plat. As discussed in our above-referenced geotechnical report, the short slope in the northwestern portion of the site is only approximately 10 feet in height, and has been created by previous fill placement in that area. The natural inclination of the ground in close proximity to this slope is substantially Jess than 40 percent. From this, it is readily apparent that the steep slope on lot 8 was created by previous grading. It is our professional opinion that no slope setback or buffer are needed on Lot 8 if the existing slope is regraded to an inclination of less than 40 percent, or 2.5:1 (Horizontal:Vertical). This would be accomplished by removing some of the existing fill soils, and could occur in conjunction with construction of a daylight basement home on the lot. All foundations, including those for rear decks, would be excavated down to dense, native soils. Placing quarry spalls or similar scour protection at the toe of the slope would also be appropriate, considering the potential for future water flow in the shallow channel along the north property line. These conclusions and recommendations were previously presented in the second paragraph of the General section in our June 19, 2009 geotechnical report. If you have any questions, or if we may be of further service, please do not hesitate to contact us. EOTECH CONSULTANTS, INC. arc R. McGinnis, P.E. Principal GEOTECH CONSULT ANTS, INC. Lakeside Real Estate Investments 3520 South 198th Street Seatac, Washington 98188 Attention: Michael Nguyen and Yvonne Bui 13256 Northeast 20th Street, Suite 16 Bellevue. Washington 98005 (425) 747-5618 FAX (425) 747-8561 June 19, 2009 -JN 09120 via email Subject: Transmittal Letter -Geotechnical Engineering Study Proposed Short Plat 18621 -116th Avenue Southeast . Renton, Washington Dear Mr. Nguyen and Ms. Bui: We are pleased to present this geotechnical engineering report for the proposed short plat to be constructed in Renton. The scope of our services consisted of exploring site surface and subsurface conditions, and then developing this report to provide recommendations for general earthwork and design criteria for foundations, retaining walls, and pavements. This work was authorized by your acceptance of our proposal, P-7798, dated May 29, 2009. The attached report contains a discussion of the study and our recommendations. Please contact us if there are any questions regarding this report, or for furthe; assistance during the design and construction phases of this project. cc: Cramer N,W, JMJ/MRM: jyb Respectfully submitted, GEOTECH CONSULTANTS, INC. Marc R McGinnis, P.E. Principal GEOTECHNICAL ENGINEERING STUDY Proposed Short Plat 18621 -116th Avenue Southeast Renton, Washington This report presents the findings and recommendations of our geotechnical engineering study for the site of the proposed short plat to be located in Renton, Washington. Development of the property is in the planning stage, and detailed plans were not made available to us. The plat plan provided to us showed site topography and the proposed configuration of.eight potential lots. Based on this information, we anticipate that the existing house and outbuilding will be removed, a new road constructed east to west at approximately the midline of the property, and a new single-family residence constructed in each new Jot. Information regarding final grades and actual house designs had not yet been completed. If storm detention is needed, it would possibly be located on the proposed northwestern lot, or under the new road. There is a 25-foot wetland buffer indicated at the northwest site comer, along the north sides of two proposed lots .. If the scope of the project changes from what we have described above, we should be provided with revised plans in order to determine if modifications to the recommendations and conclusions of this report are warranted. SITE CONDITIONS SURFACE The Vicinity Map, Plate 1, illustrates the general location of the site. The rectangular-shaped lot has 195 feet of road frontage along 116th Avenue Southeast and a depth of approximately 301 feet. It is neighbored to the south by Benson Hill Elementary School and to the north, east, and west by single-family residences. None of the residences is directly adjacent to the subject site. The residences to the north are on relatively small lots, while the houses to the west and east are on small-acreage lots. Site topography consists of mostly gentle slopes that decline toward the center of the site. Exceptions to this include a steep slope that declines steeply to very steeply over a height of approximately 10 feet to the wetland in the northwestern site comer, and a 6-foot soil berm that has been mounded along the east side of the property for landscape purposes. The short slope in the northwestern corner of the property is inconsistent with the gentle to moderate natural topography of the surrounding area, and has obviously been created by previous grading. We saw no signs of recent instability on the northwestern slope at the time of our site visits. The subject site is currently developed with a single family residence on its eastern side with an asphalt driveway running in front of the residence, and a detached garage situated at the south- central portion of the property. The central backyard is mostly gently sloping grass with a few trees. The site perimeter is overgrown with blackberry vines and numerous medium-sized deciduous trees. The area around the residence has more formal landscaping. r-FnTFr.H r.nN~l 11 TANT!=: INr. Lakeside Real Estate Investments June 19, 2009 SUBSURFACE JN 09120 Page 2 The subsurface conditions of the property were explored by excavating eight test pits at the approximate·· locations shown on the Site Exploration Plan, Plate 2. Our exploration program was based on the proposed construction, anticipated subsurface conditions and those . encountered · during exploration,andthe scope of work outlined in our proposal. The test pits were excavated on June 8, 2009 with a: rubber-tired backhoe. · A geotechnical .· engineer from our staff. observed the excavation process, logged the test pits,. and obtained . representative samples of· the soil encountered. "Grab" samples of selected subsurface soil were collected Imm the backhoe bucket. The Test Pit Logs are attached to ti1is report as Plates 3 through 6. Soil Conditions Our explorations .encountered up to 7-feet of fill soils overlying the native soils, .. The native soils typically consisted of one-half to one foot of topsoil overlying loose to medium-dense weathered silty sand with gravel that became dense and unweathered approximately 2 to 3 feet below the topsoil layer. This dense, silty sand with gravel has been compressed under the weight of glacial ice, and is commonly referred to as glacial till. We have commonly found similar weathered and glacial till soils on other sites in the vicinity. Overlying the native, glacial deposits in most of the test location were loose, silty sand fill soils as follows: 7 feet in TP-1 at ti1e northwest portion of the site, 4.5 feet in TP-2 at the southwest, 2 feet in TP-3 at the north-central, 1 to 1.5 feet in TP-3 and TP-4 at the center, 1 foot in TP-7 at the northeast, and 3 feet in TP-8 at the southeast. The results of TP-1 confirm that the steep slope in the northwest comer of the property was created by previous grading. Test pit TP-4 encountered gravel from the old septic drainfield and was terminated close to the ground surface. No obstructions were revealed by our explorations. However, debris, buried utilities, and old foundation and slab elements are commonly encountered nn sites that have had previous development. Although our explorations did not encounter cobbles or boulders, they are often found in soils that have been deposited by glaciers or fast-moving water. Groundwater Conditions Perched groundwater seepage was observed at a depth of 4 to 7 feet in test pits TP-5 and TP-8. The test pits were conducted following a relatively wet fall and winter, but were left open for only a short time period. Therefore, the seepage levels on the logs represent the location of transient water seepage and may not indicate the static groundwater·level. It should be noted that groundwater levels vary seasonally with rainfall and other factors. It is typical to find at least localized seepage perched on top of low permeability glacial till soils following extended wet weather. The stratification lines on the logs represent the approximate boundaries between soil types at the exploration locations. The actual transition between soil types may be gradual, and subsurface conditions can vary between exploration locations. The logs provide specific subsurface infonmation Lakeside Real Estate Investments June 19, 2009 JN 0912Q Page 3 only at the locations tested. The relative densities and moisture descriptions indicated on the test pit logs are interpretive descriptions based on the conditions observed during excavation . ... . ·· The compaction of test pit backfill was not in the scope of our services. Loose soil will therefore be · · found in the area of the test pits. If-this presents a problem, the backfill will need:to be removed ·· and replaced with structural-fill during construction. CONCLUSIONS AND RECOMMENDATIONS GENERAL THIS SECTION CONTAINS A SUMMARY OF OUR STUDY AND FINDINGS FOR THE PURPOSES OF A. GENERAL OVERVIEW ONLY. MORE SPECIFIC RECOMMENDATIONS AND CONCLUSIONS ARE CONTAINED IN THE REMAINDER OF THIS REPORT. ANY PARTY RELYING ON THIS REPORT SHOULD READ THE ENTIRE. DOCUMENT. The test pits conducted for this study encountered up to' 7 feet of loose, silty sand fill soils overlying native soils, though fill depths were typically on the order of 1 to 3 feet. The native soils typically. · consisted of one-half to one foot of topsoil overlying loose to medium-dense weathered silty sand with gravel that became dense and unweathered approximately 2 to 3 feet below the topsoil layer. Single-family residences may be supported on conventional foundations bearing on the medium- dense or dense, native silty sand, or on structural fill placed above this competent, native soil. No foundations, slabs or other settlement-sensitive elements should bear over the existing fill soils. In areas of deeper fill soils, particularly the northwest site comer, basements should be considered to reduce the amount of overexcavation needed to reach bearing soils. Adjacent to the steep northwest slope, structures should bear directly on dense, native soils as discussed below. The steep slope at the northwest corner of the property was created during previous grading activities and consists mostly of loose, silty sand fill soils. This slope is currently at, or near, its angle of repose, particularly near the toe of the slope. Depending on conditions at the base of the slope, future undercutting is possible from water flowing in the wetland area which could decrease the stability of the slope. This and continued weathering of the surface of the slope create the potential for some movement of the slope. .If allowed by the building department, this slope's stability could be increased by grading it back to an inclination of no more than 2.5:1 (Horizontal:Vertical), and installing large rock at the toe of the slope for scour resistance. If this slope cannot be modified to increase its stability, we recommend that all structures be set back a minimum of 15 feet from the top of the slope, and bear directly on the dense glacial till. In that way, any future soil movement on the steep slope would not adversely impact structures. Additionally, it would be importantto not place any more fill in the area above, and on, the steep slope, in order to avoid reducing Its stabilitY further. If storm water detention for the site is needed in the northwestportion of the site, a detention pond should not be used; rather a detention vault bearing on the glacial till-soils would be appropriate. If the northwest slope is not stabilized, any outlet for the storm system that extends down the northwest slope should be Installed with as limited disturbance to the slope as possible. This would require a relatively narrow and shallow trench, or installing the pipe on the surface of the slope. Also, setting catch basins or other control structures near the top of the steep slope should be avoided, as they could settle or shift due to soil movement. · Lakeside Real Estate Investments June 19, 2009 JN 09120 Page4 ' A significant geotechnica/ consideration for development of this site· is the overly moist to .wet • · , condition 0f the silty soils. Based on our observations; and the results of our laboratory tests, the moisture contents of the on-site soils are generally 10 or more percent above the-optimum moisture · content necessary .for. the• required structural fill compaction. These fine-grained, silty, soils are. , Sensitive to moisture, which· makes them. impossible· .to adequately compact when. they"have · moisture. contents even 2 to 3 percent above their optimum moisture content. The reuse of.these .. soils as structural fill to level the site will be difficult and only possible during hot, dry. weather. Aeration of each loose lift c,f soil will be required to dry it before the lift is,compacted. Alternatively, the soil cquJd be'cherriically dried by adding lime, kiln dust, or cement, .provided thisds al/Gwed by ... ·. · · responsible building department. Regardless of the method of drying, the earthwork process will . · be slowed dramatically, and we have typically found that having to dry soil before compaction is not efficient in small areas, such as beneath foundations and behind retaining walls. The earthwork contractor must be prepared to rework areas that don't achieve proper compaction due to high ·. · moisture content: Utility trench·backfill in structural areas, such as pavements; must also be dried. · before it can be adequately compacted. Improper compaction of backfill in utility trenches and arouni;l control structures . is a common reason for pavement distress and failures .. Imported granular fill· will be needed wherever it is not possible to dry the on-site ·soils sufficiently before. ·· compaction. · The erosion control measures .needed during the site development will depend · heavily on the weather conditions that are encountered. We anticipate that a silt fence will be needed around the downslope sides of any cleared areas. Rocked construction access roads should be extended into the site to reduce the amount of soil or mud carried off the property by trucks and equipment. Wherever possible, these roads should follow the alignment of planned pavements, and trucks should not be allowed to drive off of the rock-covered areas. Depending on the -construction sequencing, it would be prudent to clear on!y the areas that will be immediately worked .. Installing the road and storm system early in the project is often beneficial, as it reduces erosion problems substantially. Cut slopes and soil stockpiles should be covered with plastic during wet weather. Following rough grading, it may be necessary to mulch or hydroseed bare areas that will not be immediately covered with landscaping or an impervious surface. The drainage and/or waterproofing recommendations presented in this report are intended only to prevent active seepage from flowing through concrete walls or slabs. Even in the absence of active seepage into and beneath structures, water vapor can migrate through walls, slabs, and floors from the surrounding soil, and can even be transmitted from slabs and foundation walls due to the concrete curing process. · Water vapor also results from occupant uses, such as cooking and bathing. Excessive water vapor trapped within structures can result in a variety of undesirable conditions, including, but not limited to, moisture problems with flooring systems, excessively moist air within occupied areas, and·the growth of molds, fungi, and other biological organisms that may be harmful to the health of the occupants. The designer or architect must consider the potential vapor sources and likely occupant uses, and provide sufficient ventilation, either passive or mechanical, to prevent a build up of excessive water vapor within the planned structure. Geotech Corisu/tants, lhc. should be allowed to review the final development.plans to verify that the recommendations presented in this report are adequately addressed in the design. Such a plan review would be additional work beyond the current scope of work for this study, and it may include revisions to our recommendations to accommodate site, development, and geotechnical constraints that become more evident during the review process. Lakeside Real Estate Investments June 19, 2009 JN 09120 Page 5 : We recommend including this report; ·in its-entirety, in the project contract ·documents. This·report · ·. should also be provided to any·future property owners .. so they will be aware of our findings and ·• recommendations. · SEISMIC CONSIDERATIONS · In accordance with Table 1613,5.2 Of the 2006 ·International Building Code .(IBC), the site soil ·,.:profile within 100ieet of the .ground surface is best represented by Site.Class Type C (Very Dense -Soil and· Soft Rock). As noted in the USGS website, ·the mapped spectral acceleration value for a · 0.2 second (S,) and 1.0 second period (S 1) equals 1.36g and 0.46g, respectively.· · The dense soils that will support the new structures are not susceptible to seismic liquefaction. CONVENTIONAL FOUNDATIONS The proposed structures can· be supported on conventional continuous ahd spread footings bearing on undisturbed, medium-dense and dense, native silty sand or on structural fill placed above this competent native soil. See the section entitled· Genera/ Earthwork and Structural FIii for recommendations regarding the placement and compaction of structural fill beneath structures. Adequate compaction of structural fill should be verified with frequent density testing during fill placement. Prior to placing structural fill beneath foundations, the excavation should be observed by the geotechnical engineer to document that adequate bearing soils have been exposed. We recommend that continuous and individual spread footings have minimum widths of 16 and 24 inches, respectively. Exterior footings should also be bottomed at least 18 inches belov; the 10',vest adjacent finish ground surface for protection against frost and erosion. The local building codes should be reviewed to determine if different footing widths or embedment depths are required. Depending on the final site grades, overexcavation may be required below the footings to expose competent native soil. Unless lean concrete is used to fill an overexcavated hole, the overexcavation must be at least as wide at · the bottom as the sum of the depth of the overexcavation and the footing Width. For example, an overexcavation extending 2 feet below the bottom of a 2-foot-wide footing must be at least 4 feet wide at the base of the excavation. If lean concrete is used, the overexcavation need only extend 6 inches beyond the edges of the footing. An allowable bearing pressure of 2,500 pounds per square foot (psi) is appropriate for footings supported on medium-dense and silty sand or structural fill placed above this competent native soil. A bearing pressure of 5,000 psi can be used for the design of detention vault or retaining wall footings bearing directly on dense glacial till at least 5 feet below the existing ground surface. A one-third increase in these design bearing pressures may be used when considering short-term wind or seismic loads. For the above design .criteria, it is anticipated that the total post-construction settlement of footings founded on competent native soil, or on structural fill up to 5 feet in . thickness, will be about one-half inch, with differential settlements on the order of one-quarter inch in a distance of 50 feet along a continuous footing with a uniform load. Lateral loads due to wind or seismic forces may be resisted by friction between the foundation and the bearing soil, or by passive earth pressure acting on the vertical,. embedded portions of the foundation. For the latter condition, the foundation must be either poured directly against relatively level, undisturbed soil or be surrounded by level structural fill. Lakeside Real Estate Investments June 19, 2009 JN 09120 Page6 We· recommend· using ·11:Je following. ultimate values for the foundation'.s · resistance. to lateral, loading: Coefficient of Friction 0.45 Passive Earth P1essun,, ' .. 350 pcf . · . Where; (i) -pcf Is .pounds· per cubic foot, and (ii) passive earth pressure is computed using the equivalent fluid density. If the ground i~ front of a foundation is loose or sloping, the passive earth pressure given above will. not be appropriate. We recommend maintaining a safety factor of at least 1.5 for the foundation's resistance to lateral loading, when using the above ultimate values. PERMANENT FOVNDATION AND RETAINING WALLS Retaining walls backfilled on only one side should be designed to resist the lateral earth pressures imposed by the soil they retain. The following recommended parameters are for walls that restrain level backfill: · ~~ ,-~---·-1 I r,rn 1,rr r r1< 1 1 1u r Active Earth Pressure • 35 pcf Passive Earth Pressure · · 350 pcf Coefficient of Friction 0.45 Soll Unit Weight 135 pcf Where: (I) pcf Is pounds per cubic too~ and ~I) active and passive earth pressures are computed using the equivalent fluid pl'88SUre&. * For a restrained wall that cannot deflect at least 0.002 times Its height; a unifonn lateral pressure equal to 1 O psf times the height of the wall should be added to the above active equivalent fluid pressure. The values given above are to. be used to design only permanent foundation and retaining walls that are to be backfilled, such as conventional walls constructed of reinforced concrete or masonry. It is not appropriate to use the above earth pressures and soil unit weight to back-calculate soil strength parameters for design of other types of retaining walls, such as soldier pile, reinforced earth, modular or soil nail walls. We can assist with design of these types of walls, .if desired, The passive pressure given is appropriate for the depth of level structural fill placed in front of a retaining or foundation wall only. The values for friction and passive resistance are ultimate values and do not include a safety factor. We recommend a safety factor of at least 1.5 for overturning and sliding, when using the above values to design the walls. Restrained wall soil parameters should be utilized for a distance of 1.5 times the wall height from comers or bends in the walls. Lakeside Real Estate Investments June 19, 2009 JN 09120 Page 7 This is intended to reduce, the amount of cracking. that. can occur where a .wall is,restrained .by a. comer. The design values·given above do not ihclt.ide the effects of any hydrostatic·pressures .:behind·the' ·walls and assum!;!Jhat no-surcharges, ,such ,as those caused by slopes,vehicles, or·adjacenl'-·· · foundations will be exerted on the walls. · 1f these conditions exist, those pressures should,be added to the above lateral soil pressures. Where sloping backfill is desired behind the walls, wewill need to be given the wall dimensions and the slope of the backfill in order to provide the appropriate design earth pressures. Heavy·construction equipment should not be operated behind retaining .. · and foundation walls within. a distance equal to the height of a wall, unless the,walls · are designed . · for the additional lateral pressures resulting from the equipment. Retaining Wall Backfill Backfill · placed behind retaining or foundation walls should be coarse, free-draining structural fill containing no organics. This backfill should contain no more than 5 percent silt· or clay particles and have no gravel greater than 4 inches in diameter. The percentage of particles passing the No. 4 sieve should be between 25 and 70 percent. The on-site -soils have a high·.silt content, and are not free-draining. If the on-site soils can be dried· enough to adequately compact as wall backfill, a minimum 12-inch width of free-draining gravel should be placed against the walls for vertical drainage down to the footing drain. The purpose of these backfill requirements is to ensure that the design criteria for a retaining wall are not exceeded because of a build-up of hydrostatic pressure behind the wall. The top 12 to 18 inches of the backfill should consist of a compacted, relatively impermeable soil or topsoil, or the surface should be paved. The ground surface must also slope away from backfilled walls to reduce the potential for surface water to percolate into the backfill. It is critical that the wall backfill be placed in lifts and be properly compacted, in order for the above-recommended design earth pressures to be appropriate. The wall design criteria assume that the backfill will be well-compacted in lifts no thicker than 12 inches. The compaction of backfill near the walls should be accomplished with hand-operated equipment to prevent the walls from being overloaded by the higher soil forces that occur during .compaction. The section entitled· General Earthwork and Structural Fill contains additional recommendations regarding the placement and compaction of structural fill behind retaining and foundation walls. The above recommendations are not intended to waterproof below-grade walls, or to prevent the fonmation of mold, mildew or fungi in interior spaces. Over time, the performance of subsurface drainage systems can degrade, subsurface groundwater flow patterns can change, and utilities can break or develop leaks. Therefore, waterproofing should be provided where future seepage through the walls is not acceptable. This typically includes . limiting cold-joints and wall penetrations, and using bentonite panels or membranes on the outside of the walls. There are a variety of different waterproofing materials and systems, which should be installed by an experienced contractor familiar with the anticipated construction and subsurface conditions. Applying a thin coat of asphalt emulsion to the outside face of-a wall is not considered waterproofing, and will only help to reduce moisture generated from water vapor or capillary action from seeping through the concrete. As with any project, adequate ventilation of basement and crawl space areas is important to prevent a build up of water vapor that is commonly transmitted through concrete walls from the surrounding soil, even when seepage is not present. This is appropriate even when waterproofing is applied to the outside of foundation and retaining r.:F=nn:c:H ~nN~l II TANT~ INC: Lakeside Real Estate Investments June 19, 2009 JN 09120 Page8 walls: We recommend that you .contact a specialty consultant if detailed recommendations·· or specifications related to waterproofing design, or minimizing the potential. for infestations of mold and mildew are desired. SLABS-QNoGRADE The building floors can be constructed as slabs-on-grade atop non-organic native soils, or on structural fill. The subgrade soil must be in a finm, norFyielding condition at the time of slab · construction or underslab fill placement. Any soft areas encountered should be excavated and replaced with select, imported structural fill. Even where the exposed soils appear dry, water vapor will tend to naturally migrate upward through the soil to the new constructed space above it. This can affect moisture-sensitive flooring, cause. imperfections or damage to the slab, or simply allow excessive water vapor into the space above the slab. All interior slabs-on-grade should be underlain by a capillary break. or drainage layer consisting of ·a minimum 4sinch thickness of gravel or crushed rock that has a fines content (percent passing the No. 200 sieve) of less than 3 percent and a sand content (percent passing the No. 4 sieve) of no more than 10 percent. Where basements are utilized, a minimal underslab drainage system should be included to capture any groundwater that may bypass the perimeter footing drains. Such an underslab system would consist of at least 6 inches of gravel, in which perforated pipes would be buried on 20-to 25-foot spacing. These pipes can be laid essentially level, and be tied into the perimeter footing drain system. As noted by the American Concrete Institute (ACI) in the Guides for Concrete Floor and Slab structures; proper moisture protection is desirable immediately below any on-grade slab that wi!! be covered by tile, wood, carpet, impermeable floor coverings, or any moisture-sensitive equipment or products. ACI also notes that vapor retarders, such as 6-mil plastic sheeting, have been used in the past, but are now recommending a minimum 10-mil thickness. A vapor retarder is defined as a material with a penmeance of less than 0.3 perms, as determined by ASTM E 96. It is possible that concrete admixtures may meet this specification, although the manufacturers of the admixtures should be consulted, Where vapor retarders are used under slabs, their edges should overlap by at least 6 inches and be sealed with adhesive tape. The sheeting should extend to the foundation walls for maximum vapor protection. If no potential for vapor passage-through the slab is desired, a vapor barrier should be used. A vapor barrier, as defined by ACI, is a product with a water transmission rate of 0.01 perms when tested in accordance with ASTM E 96. Reinforced membranes having sealed overlaps can meet this requirement. DRAINAGE CDNSIDERA nDNS Foundation drains should be used where {1) crawl spaces or basements will be below a structure, (2) a slab is below the outside grade, or (3) the outside grade does not slope downward from a building. Drains should also be placed at the base of all earth-retaining walls. These drains should be surrounded by at least 6 inches of 1-inch-minus, washed rock and then wrapped in non-woven, geotextile filter fabric (Mirafi 140N, Supac 4NP, or similar material). The potential need for underslab drainage is discussed in the previous section. At its highest point, a perforated pipe invert should be at least 6 inches below the bottom of a slab floor or the level of a crawl space, and it should be sloped for drainage. All roof and surface water drains must be kept separate from the . foundation drain system. A typical drain detail is attached to this report as Plate 8. For the best long-term performance, perforated PVC pipe is recommended for all subsurface drains. Lakeside Real Estate Investments June 19, 2009 JN 09120 Page 9 As a minimum; a vapor retarder; as defined in the -Slabs-On-Grade section;. should .. be provided in any crawl space area to limit the transmission of water vapor from the underlying s.oils. Also, an outlet drain is recommended for all crawl spaces to prevent a build up of any. water· that. may . bypass the footing drains. Groundwater was observed during our field work. If seepage is encountered in an excavation, it. should be drained from the-·site by directing it through drainage ditches, perforated pipe, or, French drains, or by pumping it from: sumps interconnected by shallow connector treRches at the bottom of the excavation. · The excavation and site should be graded so that surface water is directed off the site and away from the tops of slopes. Water should not be allowed to stand in any·area where foundations, slabs, or pavements are to be constructed. Final site grading in areas adjacent to a building should slope away at least 2 percent, except where the area is paved. Surface drains should be provided where necessary to prevent ponding of water behind foundation or retaining walls. · .Water from roof, storm water, and foundation .drains should not be discharged onto slopes; it should be tightlined to a suitable outfall located away from any slopes. PAVEMENT AREAS The pavement section may be supported on competent, non-organic native soil, structural fill or on existing fill compacted to a 95 percent density. Because the site soils are silty and moisture sensitive, we recommend that the pavement subgrade be in a stable, non-yielding condition at the time of paving. Granular stn.ictura! fl!! or geotextile fabric may be needed to stabilize soft, wet, or unstable areas. To evaluate pavement subgrade strength, we recommend that a proof roll be completed with a loaded dump truck immediately before paving. In most instances where unstable subgrade conditions are encountered, an additional 12 inches of granular structural fill will stabilize the subgrade, except for very soft areas where additional fill could be required. The subgrade should be evaluated by Geotech Consultants, Inc., after the site is stripped and cut to grade. Recommendations for the compaction of structural fill beneath pavements are· given in the section entitled General Earthwork and Structural Fill. The ·performance of site pavements is directly related to the strength and stability of the underlying subgrade. The pavement for lightly loaded traffic and parking areas should consist of 2 inches of asphalt concrete (AC} over 4 inches of crushed rock base (CRB) or 3 inches of asphalt-treated base (ATB). We recommend providing heavily loaded areas, such as the new roadway, with 3 inches of AC over 6 inches of CRB or 4 inches of ATB. Increased maintenance and more frequent repairs should be expected if thinner pavement sections are used. GENERAL EARTHWORK AND STRUCTURAL FILL All building and pavement areas should be stripped of surface vegetation, topsoil, organic soil, and other deleterious material. It is important that existing foundations be removed before site development. The stripped or removed materials should not be mixed with any materials to be used as structural fill, but they could be used in non-structural areas, such as landscape beds. Structural fill is defined as any fill, including utility backfill, placed under, or close to, a building, behind permanent retaining or foundation walls, or in other areas where the underlying soil needs Lakeside Real Estate Investments June 19, 2009 JN 09120 Page 10 to support loads. All structural fill should be placed in horizontal lifts with a moisture. content at; or near, ·the optimum moisture content. The optimum.moisture .content is that moisture content that results in the greatest compacted dry density, · The moisture content of fill.· is very ·important and · must be closely controlled during the· fillin·g·and compaction process.· The allowable thickness of the fill lift will depend on the material type selected, the compaction equipment used, and the number of passes. made to compact the lift .. The. loose lift thickness. should ·not exceed 12 inches. We •recommend :testing the fill as it is placed. ·. lf the .fill is not sufficiently .compacted, it can be recompacted: before another lift is placed. -This eliminates the need to. remove the. fill-to achieve the required -compaction. The· following .table presents recommended relative compactions for structural fill: --------------------- Use of On-Site Soil I 0( \ 110:\ or I· II I I\IINl\ll 11 RI I \ rl\ I l'I \( I ~I I \ I I C O Ill'\( 110'\ Beneath footings,. slabs 95% or walkwavs .. ·.· . Filled slopes and behind . ' .. 90% retainino walls 95% for upper 12 inches of· Beneath pavements subgrade; 90% below that level Where: Minimum Relative Compaction is the ratio, expressed in percentages1 of the compacted dry density to the maximum ctry density, as detennined In accordance with ASTM Test Designation D 1557-91 (Modified Proctor). If grading activities take place during wet weather, or when the silty, on-site soil is wet, site preparation costs may be higher because of delays due to rain and the potential need to import granular flit. The on-site soil is generally silty and therefore moisture sensitive. Grading operations will be difficult during wet weather, or when the moisture content of this soil exceeds the optimum moisture content The moisture content of the silty, on-site soil must be at, or near, the optimum moisture content, as the soil cannot be consistently compacted to the required density when the moisture content is significantly greater than optimum. The moisture content of the on-site soil was generally 10 percent, or more, above the estimated optimum moisture content at the time of our explorations. The use of the underlying site soils will be difficult and are only possible if grading operations are conducted during hot, dry weather, when drying the wetter soil by aeration is possible. During excessively dry weather, however, it may be necessary to add water to achieve the optimum moisture content. Moisture-sensitive soil may also be susceptible lo excessive softening and "pumping" from construction equipment, or even foot traffic, when the moisture content is greater than the optimum moisture content. It may be beneficial to protect subgrades with a layer of imported sand or crushed rock to limit disturbance from traffic. The General section should also be reviewed for considerations related to the reuse of on-site soils. Structural fill that will be placed in wet weather should consist of a coarse, granular soil with Lakeside Real Estate investments June 19, 2009 JN 09120 Page 11 a silt or clay content of no· more than 5 percent. The percentage of particles passing the No. 200 sieve should be measuredJrom·that .portion of -soil passing the three-quarter-inch sieve. LIMITATIONS The conclusions and recommendations contained in this report are based on site conditions.as · they existed at the.time .of our exploration and cassume that the soil and groundwater .conditions encountered .in the test pits are· representative of-subsurface conditions on· the site: If the · subsurface conditions encountered during · construction are significantly · different from· those observed in our explorations, we should be advised at once so that we can review these conditions and reconsider our recommendations where necessary. Unanticipated soil conditions ·are comm·only.encountered .on construction sites, and cannot be fully anticipated by merely.tal<;ing soil samples irHest· pits,· Subsurface conditions can also vary between exploration locations, Such unexpected conditions frequently require making additional expenditures to attain a properly constructed project. It is recommended that the owner consider providing a contingency fund to . accommodate such potential extra costs and risks. This is a standard recommendation for all projects. This report has been prepared for the exclusive use of Lakeside Real Estate Investments, and its representatives, for specific application to this project and site. Our conclusions and recommendations are professional opinions derived in accordance with current standards of practice within the scope of our services and within budget and time constraints. No warranty is expressed or implied. The scope of our services does not include services related to construction safety precautions, and our recommendations are not intended to direct the contractor's methods, techniques, sequences, or procedures, except as .specifically described in our report for consideration in design. Our services also do not include assessing or minimizing the potential for biological hazards, such as mold, bacteria, mildew and fungi in either the existing or proposed site development. ADDITIONAL SERVICES In addition to reviewing the final plans, Geotech Consultants, Inc. should be retained to provide geotechnical consultation, testing, and observation services during construction. This is to confirm that subsurface conditions· are consistent with those indicated by our exploration, to evaluate whether earthwork and foundation construction activities comply with the general intent of the recommendations presented in this report, and to provide suggestions for design changes in the event subsurface conditions differ from those· anticipated prior to the start of construction. However, our work would not include the supervision or direction of the actual work of the contractor and its employees or agents. Also, job and site safety, and dimensional measurements, will be the responsibility of the contractor. During the construction phase, we will provide geotechnical observation and testing services when requested by you or your representatives. Please be aware that we can only document site work we actually observe. It is still the responsibility of your contractor or on-site construction team to verify that our recommendations are being followed, whether we are present at the site or not. The following plates are attached to complete this report: Plate 1 Vicinity Map Lakeside Real Estate Investments June 19, 2009 ,,Plate2 Plates 3-6 · Plate 7 • ,,Plate.8. ·• . ·Site Exploration Plan Test Pit Logs Grain-Size Analysis Typical Footing Drain Detail JN 09120 Page 12 We appreciate the opportunity to be of service on this project .. ff you have any questions, or ·if we . may be of further service, please do not hesitate to contact us. JMJ/MRM: jyb Respectfully submitted, GEOTECH CONSULTANTS, INC,. (tJ/&-~ Jeffrey M. Johnson _ Geote.chnical Engineer Marc R. McGinnis, P.E. Principal ..... GEOTECH ~~..,.j•.._.,..C0"1111!lNl!!SUI.;!!!!!!!•:r•~--S,•IN-C.,.. p 7 VICINITY MAP 18621 -116th Avenue Southeast Renton, Washington 'Job No: 09120 l oa'!~ne 2000 l I Plate: ,.... .. _ ··-··-. ·-··-·· ··-··-··-·· ··-··-··-r-··-··-··, ~ N ~ \ ' TP-2 ~ ·-·-·--·-·-.. _ .. __________ _ Existing Garage TP-6 ~ ---·-·---.. --_,_ .. _________ _ TP-5 ~ TP-4 ~ TP-1 \ I I I I !~ !! I Q) I ::, \ 0- t O" \ §: I O> t -\ \, ....... >-~-J / .. / /~[A • . I • ··-·--·------··-··-··--; 1-·-··-··-·-·-----·-·-·----·-·--r~--~ TP-7 . . I . . . TP-8 I;iil Existing Residence ~ -.. -··-··-· ·-··-·. -.. -· ·-··-...... ·-·· -· ·-·· -··-.. -...... • $ 116th Avenue Southeast GEOTECH CONSULTANTS, INC. fa SITE EXPLORATION PLAN 18621 -116th Avenue Southeast Renton, Washington I Job No, I Dale, I I Plate, 09120 June 2009 No Scale 2 5 10 ·15 5 10 FILL 9.8% TEST PIT 1 Description Gray-brown silty SAND with gravel, fine-to medium-grained, moist, loose (FILL) . Orange-brown silty SAND with gravel, fine-to medium-grained, moist, loose to medium-dense -becomes medium-dense -becomes gray-brown, medium-dense to dense (Sandy Glacial Till) -becomes very moist to wet * Test Pit was terminated at 14 feet on June 8, 2009. * No groundwater seepage was observed during excavation. TEST PIT 2 Description Gray-brown silty SAND with gravel, fine-to medium-grained, moist, loose (FLL) I Orange-brown silty SAND with gravel, fine-to medium-9rained, very moist, loose to medium-dense (Weathered Glacial Till) -becomes gray-brown, dense (Glacial TIii) -becomes cemented, very dense * Test Pit was terminated at 10 feet on June 8, 2009. * No groundwater seepage was observed during excavation. .. .... GEOTECH ~ CONSULTANTS,INC. TEST PIT LOG 18621 -116th Avenue SE Renton, Washington 1-.... ·~"'0!!!1£;;l!!!!!!!!!!III--!!!"' -¢ -I Date· I Logged by: I Plate: Jun~ 2009 JMJ 3 20.4% 5 10 15 15 • $ TEST PIT 3 Description , very mo1s, • Test Pit was terminated at 13 feet on June 8, 2009. · * No groundwater seepage was observed·during excavation. TEST PIT 4 Description Septic field * Test Pit was terminated at 1 foot due to Septic Field on June 8, 2009. * No groundwater seepage was observed during excavation. GEOTECH TEST PIT LOG 18621 -116th Avenue SE · Renton, Washington CONSULTANTS, INC. ;s Jpb 09120 4 Date: Logged by: Plate: June 2009 JMJ 18.8% 5 15 15.6% 5 10 15 • $ 1111111 rown s1 y loose FILL To SOI TEST PIT 5 Description Orange-brown silty SAND with gravel, fine-to medium-grained, very moist, loose -becomes gray-brown, mottled with orange, very moist to wet, medium-dense -becomes gray-brown, very moist, dense (Glacial Till) * Test Pit was terminated at 8 feet on June 8, 2009. * Slight perched groundwater seepage, between 4 to 5 feet, was observed during excavation. * Slight caving between 4 to 5 feet, was observed during excavation. TEST PIT 6 Description ray-brown mo e wit orange silty wit grave , 1ne--to medium-grained, moist, medium-dense (Glacial Till) -becomes tan-brown, dense -becomes gray-brown, cemented, very dense * Test Pit was terminated at 5.5 feet on June 8, 2009. * No groundwater seepage was observed during excavation. GEOTECH TEST PIT LOG 18621 -116th Avenue SE Renton, Washington CONSULTANTS, INC. )'-IJob 98120 I Date: I Logged by: I Piste: !!me 2PPfl JM I § 22.2% 15 • $ FILL TEST PIT7 Description • very moist, Orange-brown silty SAND with gravel, fine-to medium-grained, very moist, loose to medium-dense -becomes gray-brown, mottled with orange, dense (Glacial Till) -becomes gray-brown, partially cemented, very moist to wet * Test Pit was tenninated at 7 .5 feet on June 8, 2009. * No groundwater was observed during excavation. TEST PIT 8 Description Brown silty SAND, fine-to medium-grained, very moist, loose (FILL) Topsoil range-brown si loose to medium-dense -becomes tan-brown mottled with orange, medium-dense to dense (Glacial Till) -becomes tan-brown, dense, very moist to wet • Test Pit was tenninated at 9.5 feet on June 8, 2009. • Slight perched groundwater seepage at 7 feet was observed during excavation. * Slight caving at feet was observed during excavation. GEOTECH TEST PIT LOG 18621 -116th Avenue SE Renton, Washington CONSULTANTS, INC. I Job 09120 I O:-2009 I L~ by: I Plate: 6 Percent Passed 8 0 0 0 0 0 0 0 0 ~· 0 ..... "!:' 0, "' ... "' "' .,. "' N· 0 - #200 , 0 V . #100 / . /v ' j ...,. / ~ ~ E ·~ #40 .g g .§. C .... ., .. "' -"' ! I .. .,; II) ~ !. , 2. 1f -, 0 ~ ' "' ID .5 -!! ..: C N !. <O .!!! / ii: II) 0 #10 .i ;; 1----··-f I ID '" II) + I .I. r #4 0 0 3/8' ~ I 3/4" ~ 11/2" ~ ~ 0 ~ ~" SIEVE ANALYSIS ------·------ GEOTECH 18621 -116th Avenue Southeast CONSULTANTS, INC. Renton, Washington , • Job No: Dale: 'Plate: IJl !,II!! 09120 June 2009 7 .. ---. --.. ------- Slope backfill away from foundation. Provide surface drains where necessary. · Backfill (See text for requirements) Washed Rock (7 /8" min. size) Nonwoven Geotextile Filter Fabric· 4" min. Tlghtline Roof Drain (Do not connect to footing drain) Vapor Retarder/Barrier and Capillary Break/Drainage Layer (Refer to Report text) L_ 4" Perforated Hard PVC Pipe (Invert at least 6 inches below slab or crawl space. Slope to drain to appropriate outfall. Place holes downward.) NOTES: (1) In crawl spaces, provide an outlet drain to prevent buildup of water that bypasses the perimeter footing drains. (2) Refer to report text for additional drainage, waterproofing, and slab considerations. GEOTECH CONSULTANTS, INC. ~i/ ,. ._.,.ll!!s--p!!!!!!!!!,... ____ _ FOOTING DRAIN DETAIL 18621 -116th Avenue Southeast Renton, Washington 'Job No: 09120 I Date: I June 2009 Cramer Northwest, Inc. • Surveyors •Planners •Engineers LEVEL 1 DRAINAGE ANALYSIS OF LAKESIDE REI RENTON SHORT PLAT 18621 116TR AVE SE RENTON, WA 98058 FOR MICHAEL ~UYEN 3518 S 198 ST SEATAC, WA 98188 December 7, 2007 (REVISED JUNE 23, 2008) C.N.I. JOB NO. 2007 -115 Prepared by Paul J Nitardy, P.E. 945 N. Central. Suite #104 Kent WA 98032 (253) 852-4880 Fax (253) 852-4955 EXPIRES 11/26/2009 I w,,",_. .cramen1w .corn E-mail: cnirivcramemw.com I. TASK1 II. TASK2 Ill. TASK 3 IV. TASK4 V. TASKS TABLE OF CONTENTS STUDY AREA DEFINITION AND MAPS RESOURCE REVIEW FIELD INSPECTION DRAINAGE SYSTEM DESCRIPTION AND PROBLEM DESCRIPTIONS MITIGATION OF EXISTING OR POTENTIAL PROBLEMS TASK1 STUDY AREA D1EFINITION AND MAPS TASK 1 STUDY AREA DEFINITION This project is located at 18621 116TH AVE SE in Renton, Washington. The property is approximately 1.34 acres. WE! are proposing that the property be divided into 7 residential lots. All lots will gain access from a new subaccess road which will connect to 116th ST. The property has an existing home, gara1ie, and driveway. All existing improvements on the site will be removec! to make way for the new homes. The remainder of the site consists of a large c.entral grassy portion with trees and brush concentrated around the perimeter. The existing site drainage mainly sheet flows from the southeast to the northwest. No significant amounts of upstream flow enter the site. MAPS A vicinity map, sensitive areas map, aerial/topo map, and offsite drainage map can be found in the proceeding pages. NGUYEN -VIIClNITY MAP' S26Tk ST SE 187Tti ST S31STST $£ :'61!TH s; s lG'rtt sr ~, .. "' ~ .. ~ -s.., Q IJi \ ~ ~ ~ s. '(I,, S£ 173ROST -,. <·-. ;J\lls< ~·~_..'¢.<f '1 SE 1~'!ilff'ST-~--.. _ ~ ,t,,, SE 18'.ITTI ST # ,# SE 181ST ST SE 'lfltSTST S£ 191JT'tl ST If, Iii \;! < ·, j, ~ " i SE 19lmi ST SE t9!Ttt ST S 199TJ,t,:ST Iii Ill ~ Ii! ~ ~ 1 .i:.~i ~ \;! " ~ . < 2: i< ~~ !! ?; 'II, S£~HST SE21aTH'PI.. I~ on map hlllll been com KiDg County -atsl"f from s variety d ttxfflM Is lllblect to wlttlOLlt notk:e. Klrv countyfflllkesno repn!lll!lefll8lla.orwa1111mtios. axpi'8S& or Implied, 811 to accuracy, co.upl&M.-1, timelflw •. or ,ahls'to the u..·d such lnfQrmatlon. This document 18 not lranded for uee a a surv.y produc:t.'Kl~ County·ahall rJOt bt,liebl* for .anygeneml. apeoiil. mcllrec:t. Incidental. or COONquentlal demagn mcluctw,g, but mt llmled to, lost .wenuea-or loat prdlta 19Suting fmm1he use or misuse,i:lttre lnrCnnBllon c:ootainedoo this map. lW/ al8 d this map or Honnallon on thiS map Is prahfblted except by wrtttsn permission of King County. % :: ~ ~ w r. a' ! w ., .. > < "' ~ ~ 1903ft • ~ Ii! ~ ~ .. fP, § SE 181ST?"_ Ii! a: \ Q i " ~ r ill, IJi ~ ~ 0 :t ~ i fl! If. IJi i t ~ -- ··lQ King County NGUYEN -SENSITIVE AREAS SE 1&J'T'M P. ~t82NOST SE 1MTH' ST SE1W1TttST SC 186llt P'a.. SE1MTHST SE 1ll1fH UI. SE 191STST SE 19CITi1 I.ti SE 1tJtST CT NGUYEN -SENISITIVE AREAS (II Highlighted Feature Legend SAO Stream :';3 Chi nook Distribution f •• :,;?.. -, County Boundary ~ C-1 • Sensitive Area Noti<ae on Title I_ X Mountain Peaks Cla!l!l 2 f>canfllal CAO Shoreline Condition ti C!ass2Salmonid p_ H,gn ,.,_,/ c-3 f ~.l M.ed1urn Unclnsif,ad ¢ Low r---c Lakes and l.arge Rivers l_i Hi9'hways Streams ~ Incorporated Area ~ Floodway Streets D 100 Year Floodplain H,gnw.ry ti) SAO Wetland Anenats E:2.1 SAO Landslide l.0<.11 ~ SAO Seismic Parcels SAO Erosi1111 lnfonn8Uon lncludad on this map h8!l been QQmplled ~. King County staff from a YBnllty « 'IOlm!!l5-&na , ,.. ~-to cllanga ,wfthoUl notice. Nng County makes no 11!1J11WWWi1ta!i.lt1S or warranties, ·express or~ied, as to ac:cumcy, comptetaneus; tmellness, or ·rtlhl:a to the use cf such lnforrnaliDn. This tfocum&111. ls not irtflnded for use as a SUN8Y product. KIIJI County shall not-bl!ll llabla for·arn1 genera~·apeclal, lndiracl. Incidental. Of conseqaential· . ·ti • damages Including, but ncit lmitod to, lost reve,'ILl9Sor lost proftt!I l85Ulling from the U&e or misu911 rlthei lrlormatlon contained on ttlls ITTIQ), Any sal& of . · King County this map or Information on thlS map is prchlblled except by written permiSSlon d. KWIQ County. · NGUYEN -AERIAL The h,1i:;irmatlon Included on this map has been compiled by King county staff from a vsrtety d ~ and·ls .subpct to change without notx;;e. King County makes no ~s or warranties, express or implled, as to aca.JIBC)', complet9rle!i&. timeliness, or rtitrts to th8 use d :such-Information. This document is not Intended for use as a survey product. King County shall not be liable for anir general, .special, Indirect, Incidental, or consequentifll damages including, but oot limited to, lost revenues or IDSt profits resulting from the use or mi5uso, ~ the Information ooniained on this map. My sale of this map or information on this map Is protilbited eKCept by writton permission of King County. '· "'--'-"'.t• ... tQ King County NGUYEN-CONTOURS / 1. ! ··-- --.... ___ _ -----~ ·--· ' ,,..------ --n· ..--..... ----~---)' \ '· ' i \ l \ I / !........ __ \. ·,. _________ !. .SE 1M™ ~1· ,, ··-----· \ \ \ ·,_~..P . .,. ··-.... ) \....__ \ ___________ .. ------~------~,,,,. _____ "-->J/ _:.:=::-,' ~5,, ________ ---------------------·1~·-.• '1 .. (_,. -~ . ------I ~ ------- ---- -... __ _ ___ .,.. ...... ------- ------ ___ / ____ _ + ·, \ ... _J \ \ { / , ___ ........... ______ .-·' ------. \ ' .. .i _ __.__ __ _...,,..· ------ ·----··, .. .,. ........ , I, __ .. / ,' ' .. 0 ·,Iii 1. __ -, 'l The tnfomlllllon Included on this map haa ccmplllld by King C umy 81afffrom a variety ao1R85 a il$1Jbjaet to cnange JJOtice. Kiili County mattes no repreaentatlDna orwanantles. express or implied, as to accuracy, completl!lnes1, timeliness, er rights 1D the-1188 d 81JCh lrirormatloo. This doc:Llment is not mnded for use as.a aUMt)' product. King County lhall nol be liable for any geneml, specill, indirect. iACidental, or ~I damages including, bUt not Umited to, toat revenl.Jl!IS or lost Pfdi1s res~ from the use or mllU&e ·of tho information contained on this nap. Any sale d this map or inlormetlon on this mop la prohlblt.ed except by wriUBn permission of King County. __ I) r:..-., ( ·--- ··~.~j ____ .- ,,.. ,, ·,_ .. -.. ____ . ( ---- .,,.._ 1,) ,,;,;, . '2 ~---- ---. \ i ----- ·-------- 505 r-·----. ! 12611 ~ King County NGUYEN -CONTOURS (1/4 MILE FROM \SITE SHADED) ' ·-~,-..I ··~-,_ I._ ', ·--, r ' ' . 1.--·,. "· ti King County ~ ..... (3) . ::===== I Iii l2) • OFFSITE DRAINAGE MAP: 1 ,, -·AOO' .' .·.,.... . . ! . if Jr .", Renton School Dis1ricl Mo. 403 w-¢-, " . s 30().05 -5 F ) , waj-oist. 9:1 !ID 30 u , N~ 8 ;f J ti ,,,, 'i@ ,.sue. ~-I tCJ, @ -~,1 6m • 10 TASK 2 RESOURCE REVIEW TASK 2 RESOURCE REVIEW Adopted Basin Plans and Finalized Drainage Studies: This site is not located within a known Basin Plan. Basin Reconnaissance Summary Reports: No known reports are known to exist. Critical Drainage Area Maps: The site is not known to be located in any critical drainage areas. (FEMA) Maps: The site is located outside the 100 year fiood plain. Other Offsite Analysis Reports: Cramer Northwest, Inc. has a TIR and a Level 1 Drainage analysis for a nearby site to the east with a job number of 200:;1-042, the king county project number is L01 S0021. Sensitive Areas Folio: There are no sensitive areas located on this site. DNR Drainage Problems Maps: Not applicable. Road Drainage Problems: Not applicable. King County Soils Survey: Soil on this site consists of (AgB), Alderwood gravelly sandy loam, 0 to 6 percent slopes. Wetlands Inventory Maps: There is a wetland in the northwest corner of the site per the wetland assessment for Yvone Bui by J.S. Jones and Associates that is being prepared. Migrating River Studies: Not applicable. Drainage Complaints: There were no relevant complaints in th,e area. VV1,l1",LVV/ 1,L/llfl II• 11 \.< l'V, !I -I\ LI King County Water and Land Resources (WLR) Division 201 S Jackson St, Suite 600 Seattle, WA 98104-3855 FAX To:~ Fax: ~319$) Phone;-------- Date: Number of pages including cover sheet: __ From: Cindy Torkelson WLR Stormwater Services Section Phone: 206-296-1900 Fax Number: 206-296-0192 IMPORTANT LEVEL 1 ANALYSIS NOTE: We do not send copies of certain complaint types that are not relevant such as BCW, Fl, FIR, FIH and WQA, and we do not send CL and LS types. See key below. Type S 1, S2 and S3 will not be faxed due to size constraints. • IF YOU ARB USING THE 2005 SWM DESIGN MANUAL YOU ONLY NEED IOYRS WORTII OF COMPLA...Th!T.S The following is a list of complaint types recei,red by the Warer and Land Resources Stormwater Services Section. Complaint numbers beginning.prior to 1990-:XXXX have been archived and are no longer in our possession. They can still be retrieved, if necessary, but will take additional time and may not be beneficial to your research due to their age, development which has occurred, etc. If you are interested in reviewing the actual complaints, they can be pulled (time permitting) for your review. Copies can be obtained for$ .15 per page, and $2.00 per page for plans. Km;. Type of lnyestigatlgu C Action Rcquost BCW Be.sines.,' for Clean Waicr CCF R,spons• u, Inquiry •ct Claim EM l:!nf:oreement on Hold ER E,,forcen,ent Roview PCC,FCR,FCS Facility Complamta FI SWM Fee Inquiry FIR SWM F<e Review Fill SWM Fee on Hold "LS l.n,ruit RR Facility l!nginecring Rovi'"" NDA Neigbbolllood Drainage Assistance WQC Warec Q"'1ity Compmm WQE W-Q"'1ityED-.Ot WQR Wm Quality Engino,ring R,view WQA W-QuaJity Aud~ WQO W<1ZrQuality-Othcr Sl,S2,SN3 Engino,ringSrudies Type of Problem DCA DDM DBS Dlll PTA INQ MMA MMF MMG MMM MNM MNW SWf WQB WQD WQI REM GRT NW]) Developmel\t/Con<lrllCtion D1'aintte ~ Miscellaneol!S Drainage-&orion/Sedimentation Dnlmage-undslide/Earth Movement Diaimr.ge Teclmicll A.ui!lmrtct Drainage-G,,,,,,Hnquny M!intenanoe -Aesa:beties Mainienance • Ploodi11g Main""'""". °"""'' --Mowing Maintenance -Needs Maintenance Maitttenance-Nox.io~ Weeds SWM Fee Quc;tion, Wator Q<,.iity-Bc,t Mon,goment Praoti<cs Water Quality-Dumping WaterQuali!,y-Tilicit Connection SWM :Ft!.e-Remeasun!m!mt SWMFcc-()w,l SWM PctwNew Ois~tmt •Subject kl Public. Disc1~ ~rcmcnts l. Roccipt of writtm m:iutst. fur documents 2. Rev'i~ and appr0wl by Pro$CCUtinS Attorney's office oc-. 24 20C7 1: 111M KJNo Cv. WLKU IV\J. !"LL C. LI J DI D1WttY Water 8111 Land llesllna lliviaill -hinage Services Saclilo Clmlllallt l8arCll Pnnted: 10/23/2007 2:58:57 PM CIIIQllllllt : TffHf Prollam M*UllfPl'llllla c..iem Tlml'lul i.mllar 1975-0076 C FLOG RD WY/FLD'D/112TH AVE SE/SE 186TH ST 686E2 1979-0047 C 11403 SE204TH ST SOIL BULLDOZED/PANTHER LI< AREA 686E2 1984-0298 C FILL .18504 112THAVESE ILLEGAL NEA~ 17409 126TH AVE SE 6BBE1 1986-1166 C FLDG 11202 SE 186TH ST STORM OVE:RFLOW 686E2 1986-1185 C FLDG 11202 SE 186TH ST SEE; 86-1166 BRYANT, BILL 686E2 1986-1190 C FLOG 11001 SE 186TH ST BASEMENT GEITING WATER 686E2 1987.0334 C DRNG 11202 SE 186TH ST CULVE:RTS BLOCKED 86-1166, 1185 6B6E2 1987--0471 C FLOG 11202 SE 186TH ST SPRING GLEN 86-1166,1185 686E2 1987--0545 C DRNG 18627 109TH AVE SE INADl:QUATE SYSTEM 686E2 1989-0650 C DRNG 18631 111THPL SE S/W DRNG AND DAMAGE 68652 1989-0700 X DRNG 18631 111THPL SE WATER ON SIDEWALK/89-0650 FRITON 686E2 1990-0075 C DRNG 11254 SE 186TH ST PLUGGED CULVERT/STORM 686E2 1990-0141 C FLDG 18400 112THAVE SE POND OVERFLOW/90--0149,235,372/STOR B86E2 1990-0149 C FLOG 11202 SE 186TH ST RID POND OVERFLOW/ROBERT/ STORM E 686E2 1990-0231 C DRNG 18425 112THAVE SE RID POND OVERFLOW/STORM 90-274,37 686E2 1990-0235 C FLOG 11202 SE 186TH ST WATER IN BASEMENT/STORM/90-141,149, 686E2 1990-0274 C FLOG 11022 SE 184TH PL RID POND FLOODED/STORM 686E2 1990--0342 C FLOG 11202 SE 1Bl'ITH ST RID POND/ROBERTI STORM EVENT 686E2 1990--0372 X DRNG 11202 SE 186TH ST RID PONDS OVERFLOW9/90-141,149,235,2 686E2 1990-0709 CL FLOG 18504 112THAVE SE: CL#12959 Sl:E CL#13224 DUE DECEMBE 686E2 1990-0884 C DRNG 18427 112TH AVE SE RIO POND DRAINAGE/STORM 686E2 1990-1061 CL FLOG 11202 SE 186TH ST CL:#13224 SEE CL:#12959 GARAGE FLOO 686E2 1990-1186 CL FLDG 11044 SI: 186TH ST MEMO/RUDDELLS STUDY TO PA 686E2 1990--1212 C DITCH 11044 SE 186TH ST RD/SIDE DITCH.f'ILL/90-1186 686E2 1990-1212 E FILL/DIT 11044 SE 186TH ST WILL ST ART WORK 09/20 CHK ON Oll/30/93 686E2 1990-1212 ER FIWDIT 11044 SE 186TH ST RUDELL$ STUDY 6861:2 1990-1226 C DRNG 18615 107THAVE SE: FLOODED BASE:MENT/BAD ROADWAY 686E2 1990-1445 C DRNG 18427 112THAVE SE RID POND OVERFLOWING TO STUDY/91-1 686E2 1990-1530 SR FLOG 18427 112THAVE SE STORM EVENT 686E2 1990-1531 SR FLOG 18427 11ZTHAVE SI: STORM E:VENT NOT NDAP 6861:2 1991--0150 C DRNG 18624 112THAVE SE 686E2 1991--0150 SR DRNG 18624 112THAVE SE NOTNDAP 686E2 1991--0196 C FLOG 18425 112THAVE SE: 686E2 1991--0196 SR FLDG 18426 112TH AVE SE NOTNOAP 686E2 1991--0253 C DRNG 11254 SE 186TH ST 686E2 1991-0438 S1 SPK TO FINISH S1 3/4 -S2 TO '92 CON 68BE2 1991--0667 CL DRNG 18427 112THAVE SE SEE 91.0438 SEE RUDDELLS 686E2 v i_f) (I T'ilf'.fl 19 yrit;· Page 1 of2 ~ r,J•T 1 µVfS :-1 Gil-•ff) V\J I, L-:, l V\1 f , L I Ill cmnJ)llllt TJt)D TJJB uf l'nllllm Adnss of Prt*IBII ca-ts Tlrlll'IP ...... cad& 1991-<JB37 C DAMAGECB 19001 11ITTHAVE SE GIB BELOW GRADE 686E2 1991-1096 C FLDG 11200 SE 186TH ST RUDDELL POND OVERFLOW 686E2 .;;. "'- 1991-1132 C DRAINAGE 19006 116THAVE SE INFOTOPM&D 6861:2 :1:- 1991-1149 X FLDGRID 11200 SE 184TH ST CCF# SWM-1031 RID POND CAPICrTY 686E2 -: " -1994-0038 C PONDING 11430 SE 192ND ST POSS GRADING/FILLING VIOLATION 686E2 <' !: "'-> 1994-0144 C DRNG 17925 116TH AVE SE POSS FILLING VIOUACT PLAT MORNING G 6B6E1 ;. ~ 1995.0200 C DITCH ?S 18204 116TH AVE SE LACK OF CONVEYAYNCE ON PVT PROPE 6B6E1 ~ 1--"' . 1096-0805 C DRNG 19400 120TH AVE SE DRAINGE FLOW QUESTION DEVELOP INF 686E2 -l :.. C '-' 1996-1564 C DRNG 18908 113THWAY SE P~IVATE PROPERTY IMPACT TO PVT ORN 686E2 1996-2071 C FLDG 11828 SE 180TH ST INADEQUATE CONVEYANCE OFFSITE FLO 686E1 1996-2071 R FLOG 11a2a SE 180TH ST INADEQUATE CONVEYANCE OFFSITE FLO 686E1 N/fi 1997-1123 C GRADING 18908 113THWAY SE PVT PROP IMPACT NO DRNG INSTALLED 686E2 >'II/ 1997-1123 R GRADING 18908 113THWAY SE PVT PROP IMPACT NO DRNG INSTALLED 686E2 /ill? 1998-0019 C DRAINAGE 19016 116THAVE SE NEW GRAVEL RD POSSIBLE PVT PROP IM 6B6E2 /J /If 1998-0058 C DRAINAGE 18820 116THAVE SE SFR CONST IMPACTING ADJACENT PROP 686E2 tv/1, 1999-<1306 C DRAINAGE 11618 SE 188TH ST ADJACENT PROP PAVED 2500 SQ FT 686E2 µ /ti 2000-0572 C DDM ACROS 19029 120TH AVE SE APPARENT FILLING OF ROADSIDE DITCH. 6B6E2 HJ/:. 2000.0572 R DOM ACROS 19029 120TH AVE SE APPARENT FILLING OF ROADSIDE DITCH. 6B6E2 11/n 2001-0322 woo 11631 SE 184TH ST APPARENT GREY WATER DISCHARGE INT 686E1 ti/ti 2001-0322 woe woo 11631 SE 18411-1 sT APPARENT GREY WATER DISCHARGE INT 686E1 f'IIA 2001-<1389 WQC WQI SE 180T &118THAVE SE POTIENTIAL GRAY WATER DISCHARGE. C 686E1 /v/fi 2001-<1389 WOE Wal SE 180T &11BTHAVE SE POTENTIALGRAYVVATER DISCHARGE. C 686E~ N/A 2001-0389 WQR WQI SE 1BOT & 11BTHAVE SE POTENTIALGRAYWATER DISCHARGE. C 686E1 ('J)f/ 2002-0314 C DOM 18524 114THAVESE SHEETFLOW ONTO PROPERTY FROM UP 686E1 /J/tl 2002-0381 C DOM 11625 SE 184TH ST SOGGYAREAINYARD. MAY8E11-!ERES 686E1 rJ Jf! 2002--0563 C DTA 19013 114TH CTSE CONCERN REGARDING POSSIBLE SLOUG 686E2 rJ/11 2003--0847 C DOM 19230 116THAVESE APPARENT OBSTRUCTION OF OFl'SITE C 686E2 f,J//j 2003--0847 NOA-DOM 19230 116THAVESE APPARENT OBSTRUCTION OF OFFSITE C 686E2 /viii 2003-0847 R DDM 19230 116TH AVE SE APPARENT OBSTRUCTION OF OFFSITE C 686E2 f/fi 2005-<1428 C RFN 19128 113TH WY SE w.i,,r flows aoross sidewalk from water meter. 686E2 /J/Jl 2005-0440 woe WQDR 11447 SE 180TI-I PL DUMPING FROM RV 686E1 (v In 2005-0468 woe WOI 11700 SE 184TI-I ST 6B6E1 N/P 2005-0491 C DCA 17830 116THAVE SE Filling/re-grading on neighbor's property. Inv di 686E1 /V/ f! 2005-06B2 FCR MNM 19133 113THWY SE Referml from KC Health. Rat• in D91898. Inv I 68BE2 ,;/Fi 2006-0173 woe WODR 11447 SE 180TH PL RV leaving \!al of sewage. 686E1 ,,1// 2006-0173 WOR WQOR 11447 SE 180TH PL RV leaving \ran of sawage.Letter ,ent RV was 686E1 * 2006-0209 C RFN 1B621 116TH AVE SE Broken drainage pipe @ Benson Hill Elem Sch 688E2 ~ 2006-<l450 C OTA 18621 116THAVE SE School const causing water seepage into yard. 686E2 HIP 2007.oosa woe WQDR 18005 113TI-IAVE SE Car leaks gas/oil. B86E1 fll/11 2007-0221 C OTA 19128 113TI-I WY SE Request pe1T11ission to remove wg from traet. I 686E2 Pags2 of2 ' U~,.LJ,/VGI /:JUAW' ~lllo VJ. WLKU l~'J, I": J \) King County Water and Land Resources (WLR) Division 201 S Jackson St, Suite 600 Seattle, WA 98104-3855 Date: /0/2@'7 ·---"--,7'-~f-. ~------ FAX Number of pages including cover sheet: To: Fax: From: Candi McKay, Eng Tech II WLR Stormwater Services Section Phone: 206-296-1900 Fax Number: 206-296-0192 IMPORTANT LEVEL 1 ANALYSIS NOTE: We do not send copies of certain complaint types that are not relevant such as BCW, FI, Fm, FIH, SUP and WQA, and we do not send CL and LS types. See key below. Type S1, S2 and S3 will not be faxed due to size constraints. The following is a list of complainl tn,es received by fae Water Olld Land Resources Division Drainage Services Section. Complaint numbers beginning prior to 1990-XXXX hlJvo been archived and are no longer in our possess.ion. They can still be retrieved, if necessery, but will take additional time and may not be beneficial to your research due to their age, development which bas occurred, etc. If you are interested in reviewing the actual complaints, they can be pulled (time pennitting) for your review. Copies can be obtained for S .15 per page, and $2.00 porpage fur plans. Keys: Type oflnve.stigatlon Type of Prpblem BCW Busloess' for Clean Water ACS C Action Reqnert ~:Sll *CL Oalm (!l)T E-H/R Enfore~me:nt Dh Ho~ew DCA EM Mainbm.ance. Euian:emellt IlDM FCcyCR,FCS Facility Complainh IIES FI-R/H ·swM Fee ln.quiry Re.view/Hold I1LE I Inquiry DTA •LS LBW!1t1it ERQ NOA Neighborllood Drainage .Anistance ORT RET Retrofll f.lclllty IJ~Q R/Rll Engloeertng Revlew/Facllily Re•""' r.~G Sl,S2,SN3 Enginetrln~ Stodl<r LSP SUP/F Special Use Pt:rmit/F1nal MMA WQC w,i.r Quality Complaint MMFIG/lll WQAPIP Wmr Quality Andi< Jo Progr..,/Pennit MSQ WQE/R Water Quality Ertforcement/Revie.w fi,'WI)JSFl'I) X CCF or R;~ponse to Inquiry llFN REM/GRT = SGN SK!! Stl< SWF ·TRE WQRIM Accw Bioswale r-otront Cotnmotcial neten:ntn~tJon DBW1apm1mt/Constructlon Dn.imge .. Mls"lb.D80US Dninage-Erosion/Sedimentation ))nl11.11ge-Lmdsllde/E.uth Mowment Dr11inage Technica:1.Auhtan~ Eortbquake Gront Praft11}n G....-.II•qwty lnipllo• Land,"'plng Mainteunce Aestlletict Maiateuance Floodi.ng/Genenil/Mo-.ring Mosquitoes Nffi Dlseoants / 65~10 Discount Runoff from N~bbo, SWM Fee Re-mcasnnment/Grant Reln>fit f<lo!llty Signs stnkBole Storage SWM Fee Que.,tions TreeRemo..i Water Quality -11:ut Man.11gement Ptacticti/Dumpingll.lUdt connection tn Utility !nm Ration YRD \/ .,.d Extenllon •Subject to Public Disclosure requirements 1. Receipt of written request for' documents 2. Review and approv•l by Prosecuting Attorney's office ,l, VVl,L.1•0:.VV' ,J'J"'" ,..,, __ KING COUNTY WATER AND LMID RESOURCES DIVISION DRAINAGE INVESTIGATION REPORT LJ.:1 :"/ , INVESpGATIONREQlJEST Type~ PROBLEM: ~ {£fl.dl/N fJl/1V ft REcE!VBDBY: ~ Date:,~rlotr, OK'd by: Ll it FILE NO, 2006-oJl/' Received from: .I ~ ~ =... ~ ~;t~~1!;J;~-~?1a{ LoCATION OF PROBLEM, IF DIFFERENT: .,-x.(j ;,..!Id N\'l>'J ~ ·fJ.;/1'1Q,dJf?t.PI/ Plat name: N'/700-1 f:,11rIV/V' fotNo: Block No: Parcel No,,6 .J. 45(12-2/f:1 Kron i::fd_ Th.Bros: New (?nf (5,2 RDP Basin f;(J< Council District 5 _ City ___ Charge No. ______ _ RliSPON$£: Citizen notified on _____ by, _ phone __ letter _ in person DJSrosmoN: Turned to on _...J../ _ _,_/ _ by __ OR: No further action recommended because: _ Lead agency has been notified:. _____________________ _ _ · _ Problem has been corrected. _ No problem has bE:en identified. _ Prior investigation addresses problem: / SJ:E FILE# . _ Private problem -NDAP will not consider because: (D1{i't4 t"4"'• hl:M ,0 r,..,r, er S:~e, 'l::it,ct1c r{J,, LA110•"'"). __ Water originates onsite and/or onnei:ghboringparcei. tff·~~-1/'f,'O. __ Other (Specify): DATECLOSED: 'f-((.,..::;oh By: T'- INfo Tt:uvw~p ',. ®'~;~~~"o~~~~~7~~~~=' Department ofNatural Resou;ces ADDRESS 18621 1161h AVE SE Water and Land Resource Division PHONE 206-799--4?04 686E2 TIIPAGE DRAINAGE INVESTIGATION REPORT FIELD INVESTIGATION DETAlLS OF INVESTIGATION: KROLLPAGE MAINT. DIVlS!ON 604 DATE 4-19-06 4 INITIALS· SAB N'tS Met with Roger to investigate his report of a possible storm water pipe broken on the Benson Hill Elementary School property adjacent to his property. Roger claims the pipe had become broken in the past and it was repaired fixing his water problem. He feels that the pipeline has become broken again during the remodel of the school last year. The pipe is old 12" T&G concrete. I was unable to find any obvious breaks in the line. I spoke with the ODES inspector Jay Huh who was inspecting the construction and he said he 'had not heard of the 'problem. I 12" CP ~I + -~--~~~=--~ 2:.m!f----- l~V. I 't JIJ I' 0 Cqmplaint 2006-0299 Photos taken by: Bergrud, Shawn Photo !: Facing east looking at Property line between school ond pfluger's property. Photo 3: Facing e4St looking at wet area on roger's property. Photo 2: Facing west looking at port of drainage system that Roger believes is causing the problem. Photo 4: Facing east. ~I, LJ, Ltll)/ I , ) I r\1VI I\. I'll, V\J, II L 1\U KING COUNTY WATER ANO LAND RESOURCES DIVISION DRAINAGE lNvESTIGATION REPORT INVESTIGATION REQUEST PROBLEM: fi/2.u.,,v.4 /JJ'rH.? RECEIVED BY: :3&%~ OK'dby: FILENo. 2006-t1f'5c'J Received from: NA.ME: f2o.DS6,e PPL vtie& ADDRESS: /$2/ //{/ .. ,.,.! ,4U/£ c;c.. (Day) q,;>6 l ;<,:(-(Eve) PHONE '170'-/ ) ------ City ~~ State_M_ Zip __ LocATION OF PROBLEM, IF DIFFBRENT: Access Permission Granted O Call First (Would Like To Be Present) D ~ 5~fr+-1:J up r"-1 y¥o poif ~ (7w< ~~~. l9G-111..r Plat name: Lot No: Block No: 4 L S T R Parcel No..3ct:d::30S~ //,3 Iv:oll Id)!{ Th.Bros: New b'[fof,).. RDP Basin f;lK Couo.cilDistrict 5 _ City_~--ChllrgeNo. ______ _ R.l'SPoNSE: Citizen notified on by: _ phone __ lotter _ in pei:son f.1'7/· w/ fdD~ e>.r 6'11..(y;6 • · /jWlPV,-\t, ~ v,,.,~ f~ ~ tGff ,v,.f,b HAI. --JAE b-~Cl{,:, -$pPJ-e I: ;6 6 -zf> jtt11t;f-,.,v/, ~ b -z.c, -01,o HI,. ,,_µ.J 4/?fJ ffe...r. 7"I:) f>w-d-,t.Pi,/.. 7 {:::airo~d~ef/r!/rJ,6 on / / by __ OR: No further action recommended because: ..:f_ Lead agency has been notified:.~l~<_c __ .b_2l_l~S _______________ _ _ · _ Problem has been corrected. _ No problem has been identified. _ Prior investigation addresses problem: SEE FILE# --- _ Private problem -NDAP will oot consider because: __ Water origioates onsite and/or on neighboring parcel. _Other (Specify): DATECLOSED: & 1 8 /OP By: TL f?..EFF:Qct, t'o ./)!) ES DRAINAGE INVESTIGATION REPORT FIELD INVESTIGATION DETAILS OF INVESTIGATION: FILE NO. NAME Rod erPflu er ADDRESS 18621116thAVESE PHONE 799-4704 TB PAGE 686E2 KROLLPAGE 604 DATE 6-16-06 MAINT.DIVISION 4 INITIALS SAB ~ On site to investigate Rodgers report of a ground water problem post ROW construction.NT& Rodger believes that the construction has increased the flow of storm water into the ground near the comer of his property. He believes this ground water is following the sewer main ditch line in the ROW and then down his sidti sewer ditch line and surfacing in his back yard. During the my investigation I found what appears to be a defective joint in the pipe that drains the schools storm water into the ROW storm sys1em. The joint is directly above the sanitary sewer line. The water from the defective joint may be saturating the sewer ditch line and following the ditch line to surface in Rodger's property. The ROW improvements are still under performance bond. I contacted Jae Huh at DOES. We met on 6-20-06 and Jae added testing and possible repair of the pipe joint in question to the construction punch list (see attached e-mail). SKETCH: • f • Parking V\il,L'.J,LV\JI ,',Jln!TI <\ .l I'll.I \IV, !1 "-1\\.1 "-,L.13.JJl'-••ttilmi ;---.. UM Complaint 2006-0450 ;IQ.!&$2 Photos taken by: Bergrud, Shawn Photo 1: Fttcing west looking ttt soturated area in Rodger's property. Photo 3: Facing north looking from ROW. Photo 2: Facing west looking from ROW. Photo 4: Facing north looking at bioswale CB from parking lot. Vi., I. L '). L l' U ,I I : J I hlVI 1\111(: VV, 11LI\L.I "'-'' i ; .JV ' • V ~i..·---·------. Complaint 2006-0450 ·"4...-, '-,_I ,- ·.; • ' ,,~ ll" Photos taken by: Bergrud, Shawn Photo 5: Facing south looking ot rodger's driveway and ROW improvements. Photo 7 Photo 6: Facing west looking down toward Rodger's property. Photo 8 ·1 ' 01/10/2008 12: 41 213£9337478 !UrrON STATON PAGE 02/02 ··1 . ,_ . ...., . ,.-Ii c/1£/-lj; '/.D INFILTRATJONTEST&OBSERVATIONS Date: Ocrober 2!.Z®7 Site addral: 18621 11(;11> Ave.$. Ren,ton WA Job No. 2007-J 15 . . ... . • Client: Michael Ngyuen SQILLQGS: As requested, soil log boles were dug 81 th1! a!YOYe .referem:ed. pan.:e! of land. Soil log# l: 0 -. 30" +di$1:urlied soil Soil log # 2: o -24" + di5tutbed/ fill soil, 24" -34n + disturbed black Sand}> loam wilh poor stru.:ture. Soil log # 3: 0 -10" + distlllbed &Oil 1'iith latge eonaete pic,ces. Soil log# 4: 0 -24" +dilitUtbedsoil1'iith large ~pieces. Soil log# 5: 0-IO" distmbed :soil, 10" -30" +washed rook mixed with washed M«lium to COU111e• sand. (oo ltUetute)- Soil log # 6: 0 -38" + disturbed soil/ fill ··f)H!CeS of plastic found @ 34~. WATER DRQPTEST; Soil logs: due to fill and disturbed ll>ils no Wltllf droJ> test was~ This sire appeaa to •w had a sigJiiii.eant llll1GUllt of~. with fill dirt and debris placed and buried over a large porlion of this property. Oiisiteimiltratioo.·appc,alSto.not be.appropriate fur this site. No other oignifil:am ssonn -water issue& Wl!R tJbServed on this site or ~ ptoperlies. If you have any question$please \:Olltllllt meat ~93,1-7478. TASK 3 FIELD INSPECTION TASK 3 FIELD INSPECTION A field inspection was conducted on Octooer 23, 2007, to inspect the onsite drainage system of the site. Offsite drainage systems were also inspected downstream approximately 1/4 mile(s) from the discharge point of the site. The inspection involved investigation of the ten specific items of a Level 1 Inspection per the King County Surface Vlater Design Manual, 2005. The inspection yielded the following findings: 1. There were no existing or potential pmblems observed. 2. The existing drainage system capacity was adequate. 3. There were no existing or potential flo,:>ding problems. 4. There were no existing or potential sedimentation, scouring or bank sloughing problems. 5. No significant destruction of aquatic habitat or organisms was noticeable. 6. Qualitative data such as land use, impervious surfaces, topography, and soil types was noted and can be found in Task 4 information. 7. Information was collected on pipes, ditches, and structures. This information is also included in the Task 4 information. 8. Tributary basins delineated in Task 1 were verified. 9. No neighbors were contacted. 1 O. The weather conditions at the time c~ the inspection were sunny and mild. TASK 4 DRAINAGE SYSTEM DESCRIPTION AND PROBLEM DESCRIPTIONS TASK 4 DRAINAGE SYSTEM DESCRIPTION AND PROBLEM DESCRIPTIONS Site Drainage This project is located at 18621116TH AVE SE in Renton, Washington. The property is approximately 1.34 acres. We are proposing that the property be divided into 7 residential lots. All lots wil! gain access from a new subaccess road which will connect to 1161h ST. The property has an existing home, gara,;ie, and driveway. All existing improvements on the site will be removed to make way for the new homes. The remainder of the site consists of a large c-.entral grassy portion with trees and brush concentrated around the perimeter. The existing site drainage mainly sheet flows from the southeast to the northwest. No significant amounts of upstream flow enter the site. Soil on this site consists of (AgB), Alderwood gravelly sandy loam, 0 to 6 percent slopes. Offsite Drainage Off-Site Analysis Drainage System Tables are provided on the following pages that describe in detail the offsite drainage components at least Y4 mile downstream from the project discharge location. Please refer to the offsite drainage map in Task 1 because the map symbols listed in the tables correspond to drainage component symbols on the offsite drainage map. Please note that the dotted line on the offsite drainage map represents the approximate flow path that the water uses to leave the site. Part A begins at the western property line since the following tables are for the offsite information. More notes on part A and the northwest part of the site. Please aware that since the initial level ' was done, a wetland has been identified in the northwest corner of the site. The flows have and will continue to flow through this wetland. The wetland has two basic modes that would allow water to leave it. First, water can soak into the ground, second, water could sheet flow across the properties that occupy the space between the site and SE 1861h ST. (*) = SEE PHOTO Basin: Black River Symbol I Drainage Component Type, Name, and Size see map I Type; she'et flow, swale, stream, channel, pipe, pond; Size: diameter, surface area A I Sheet flow B I 12" CPP w/CB's C f 12" pipe w/Cb's j (CPP and Cone) Pl OFF-SITE ANALYSIS DRAINAGE SYSTEM TABLE SURFACE WATER DESIGN MANUAL, CORE REQUIREMENT #2 Subbasin Name: Subbasin Number: Drainage Slope Distance Existing Potential Observations of field Component from site Problems Problems inspector, resource Description discharge reviewer, or resident_ drainage basin, vegetation, % %ml= 1,320ft. constrictions, under capacity, ponding, tributary area, likelihood of problem, cover, depth, type of sensitive overtopplng, Hooding, habitat or organism overflow pathways, potential area, volume destruction, scouring, bank sloughing, Impacts sedimentation, Incision. other erosion Flows NW over dirt 3 O' -300' None None Added water near house and grass (*) Flows west Small 300' -380' None None No problems observed (*) Flows north Small 380'-410' None None No problems observed (*) !' ,s i i P2 P3 Top of picture is towards the NW. The back of Top of picture is towards the west. The Top of picture is towards the north. The end the house on lot 4 can be seen in the beginning of "B". of "B", and the beginning of "C" background. 98-4\inB04 (*) = SEE PHOTO Basin: Black River Symbol I Drainage Component Type, Name, and Size see map I Type: sheet fiow, swale, stream, channel, pipe, pond; Size: diameter, surface area D I 12" pipe w/CB 's (CPP and Cone.) E j 12" Cone. w/CB's (CPP at bend) F I 12" Cone. w/CB's f P4 OFF-SITE ANALYSIS DRAINAGE SYSTEM TABLE SURFACE WATER DESIGN MANUAL, CORE REQUIREMENT #2 Subbasin Name: Subbasin Number: Drainage Slope Distance Existing Potential Observations of field Component from site Problems Problems inspector, resource Description discharge reviewer, or resident drainage basin, vegetation, % %ml= 1,320ft. constrictions, under capacity, ponding, tributary area, likelihood Of problem, cover, depth, type of sensitive overtopping, Hooding, habitat or organism overflow pathways, potential area, volume destruction, scouring, bank sloughing, Impacts sedimentation Incision. other erosion Flows northwest Small 410'-465' None I None I No problems observed (*) I Flows north. I Small I 465'-545' I None I None I No problems observed (*) I Flows west I 6 I 545'-1,175' !None I None I No problems observed (*) Ill' 1 i'; ;,,i,17 PS P6 Top of picture is towards the north. The end of "C" and the beginning of"D". Top of picture is towards the north. The end of "D" and the beginning of "E". Top of picture is towards the east The end of"F" and the beginnin~ of"G". 98-4\inl:304 (*) = SEE PHOTO Basin: Black River Symbol G H I I f ,6 see map Drainage Component Type, Name, and Size Type: sheet How, swale, stream, channel, pipe, pond; Size: diameter, surface area 24" PVC w/CB's (also CPP used) Pond, grass and p ......... ..-1 ~ '""S""tat~ ..... .,., I uuu ·~ ~ .. u .. 24" CPP w/CB's P7 OFF-SITE ANALYSIS DRAINAGE SYSTEM TABLE SURFACE WATER DESIGN MANUAL, CORE REQUIREMENT #2 Subbasin Name: Subbasin Number: Drainage Slope !Distance Existing Potential Observations of field Component from site Problems Problems inspector, resource Description discharae reviewer, or resident drainage basin, vegetation, % %ml= 1,320ft. constricUons, under capacity, ponding, tributary area, likelihood of problem, oover, depth, type of sensitive overtopplng, flooding, habitat or organism overflow pathways, potential area, volume destruction, scouring, bank sloughing, impacts sedimentation Incision. other erosion Flows north and then Small l,175'-1,445' None None No problems observed (*) northwest Flows west, see next Small l,445'-1,545' None None No problems observed (*) I two pages fer mere. Flows west I Small J 1,545' -1, 775' None None No problems observed (*) J: c~~~ ~., .\ E r1c i ", .-i;,,, -----, P8 P9 Top of picture is towards the northwest. This is Top of picture is towards the east. A pond inlet Top of picture is towards the north. in the last structure upstream of the pond. can be seen in the background. 98-4\in804 PROJECT NO. FACILITY SKETCH SHEET TB PAGE MAINT. DIVISION OUT OF SERVICE D SPECIAL USE PERMIT 0NOMOW • MOW 2 I oo SQ IJ.i) S . D SPECIAL MOW 5 FT CHAIN LINK FENCE SE 184TH PL PVT RD U 7 c> '71 Lf 6B&D1 090914 FOUR NO J TYPE POND DATE 05 4 9 INITIALS • PJS w en w > <( :c ... N or-- TASK 5 MITIGATION OF EXISTING OR POTENTIAL PROBLEMS TASK 5 MITIGATION OF EXISTING OR POTENTIAL PROBLEMS After a thorough field inspection and a detailed resource review there were no existing or potential documented problems. Complaint numbers 2006-0299 and 2006-0454 are upstream from our site and if any problem still exists it can be addressed when our site is being developed. The proposed improvements will not produce a significant impact to the existing drainage patterns once the site has been stabilized, and the runoff has been controlled via a combined detention/wet vault. A temporary erosion and sedimentation control plan will be created at the final design stage to minimize the transport of sediment laden runoff to the downstream conveyance system.