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14-101020 (2)I I hereby state that this Abbreviated Technical Information Report for PowellsWood Garden has been prepared by me or under my supervision, and meets the standard of care and expertise that is usual and customary in this community for professional engineers. I understand that the City of Federal Way does not and will not assume liability for the sufficiency, suitability, or performance of drainage facilities prepared by me. Abbreviated Technical Information Report PREPARED FOR: Monte Powell 430 South Dash Point Road Federal Way, WA 98003 PROJECT.' PowellsWood Garden Overflow Parking Lot 430 South Dash Point Road Federal Way, WA 98003 2140097.10 PREPARED BY.' Ryan M. Jeffries, PE Project Engineer Lucas Johnson, PE, LEED AP Project Engineer REVIEWED BY.' Doreen S. Gavin, PE, LEED AP BD+C Principal DATE.' March 2014 Revised May 2014 Table of Contents 1.0 Project Overview........................................................................................................1-1 1.1 Purpose and Scope..................................................................................................1-1 1.2 Existing Conditions ............................ ....................................................................... 1-1 1.3 Post -Development Conditions ................................................ ................................... 1-1 1.4 Drainage Basins.......................................................................................................1-2 1.5 Wetland Protection...................................................................................................1-2 Section 1.0 Figures Figure 1-1 ......... Site Location Map Figure 1-2 ......... Existing Site Map Figure 1-3 ......... Developed Site Map 2.0 Conditions and Requirements Summary.................................................................... 2-1 2.1 Core Requirements..................................................................................................2-1 2.1.1 C.R. #1— Discharge at the Natural Location..................................................2-1 2.1.2 C.R. #2 — Offsite Analysis.............................................................................2-1 2.1.3 C.R. #3 — Flow Control.................................................................................2-1 2.1.4 C.R. #4 — Conveyance System......................................................................2-1 2.1.5 C.R. #5 — Erosion and Sediment Control........................................................2-1 2.1.6 C.R. #6 — Maintenance and Operations.........................................................2-1 2.1.7 C.R. #7 — Financial Guarantees and Liability ..................................................2-1 2.1.8 C.R. #8 — Water Quality ...............................................................................2-2 2.2 Special Requirements....... _ .......................... ........................................................... 2-2 2.2.1 S.R. #1— Other Adopted Area -Specific Requirements .... ,................. ..............2-2 2.2.2 S.R. #2 — Floodplain/Floodway Delineation....................................................2-2 2.2.3 S.R. #3 — Flood Protection Facilities..............................................................2-2 2.2.4 S.R. #4 — Source Controls............................................................................2-2 2.2.5 S.R. #5 — Oil Control ............. ....................................................................... 2-2 3.0 Offsite Analysis...........................................................................................................3-1 3.1 Level One Downstream Analysis................................................................................3-1 Section 3.0 Figures Figure 3-1......... Level One Map Abbreviated Technical Information Report = a PowellsWood Garden Overflow Parking Lot 2140097.10 4.0 Flow Control and Water Quality Facility Analysis and Design .................................... 4-1 4.1 Flow Control............................................................................................................4-1 4.2 Water Quality System ........................................... .................................................... 4-1 Section 4.0 Figures Figure 4-1 ......... PowellsWood Garden Storm Calculations 5.0 Conveyance System Analysis and Design................................................................... 5-1 6.0 Special Reports and Studies....................................................................................... 6-1 Section 6.0 Figures Figure 6-1 ......... Geotechnical Engineering Report South Sound Geotechnical Consulting 7.0 Other Permits............................................................................................................. 7-1 8.0 ESC Analysis and Design............................................................................................. 8-1 8.1 ESC Plan Analysis and Design...................................................................................8-1 8.2 Sensitive Area Restrictions..................................................... .................................. 8-1 8.3 ESC Maintenance.....................................................................................................8-2 8.3.1 ESC Supervisor............................................................................................8-2 8.3.2 Documentation............................................................................................8-2 8.3.3 Review Timing.............................................................................................8-2 9.0 Bond Quantities, Facility Summaries, and Declaration.of Covenant .......................... 9-1 10.0 Operations and Maintenance Plan............................................................................10-1 11.0 Conclusion................................................................................................................11-1 Abbreviated Technical Information port 13M103 PowellsWood Garden Overflow Parking Lot 2140097.10 1.0 PROJECT OVERVIEW 1.1 Purpose and Scope This abbreviated report accompanies the civil engineering plans and documents for the PowellsWood Garden Overflow Parking Lot project located at Parcel Nos. 052104-9012 and 052104-9055 in the city of Federal Way, King County, Washington. The parcels on which the project is proposed to be constructed are approximately 2.14 acres in size. These parcels are a portion of the Southwest Quarter of Section 5, Township 21 North, Range 4 East of the Willamette Meridian. See Figure 1-1 for a Site Location Map. The project proposes to remove some of the existing outbuildings, fences, and driveway, and to convert the lot (Parcel No. 052104-9012) to an overflow parking lot adjacent to the lot on which PowellsWood Garden is located (Parcel No. 052104-9055). The onsite surfaces are to be gravel, vegetated permeable paving, and pavers, all of which are permeable. A 28-foot wide paved vehicular access is to be constructed off South Dash Point Road. Stormwater management is to comply with the 2009 King County Surface Water Design Manua/ (KCSWOM) and the City of Federal Way Addendum to the KCSWOM. The site is located in a Conservation Flow Control Area and is subject to Level 2 Flow Control standards. It is also located in an area that is subject to the Enhanced Basic Water Quality Treatment menu requirements. These requirements may be reduced to the Basic Water Quality Treatment menu requirements, however. This reduction is discussed in more detail below. 1.2 Existing Conditions The overflow parking lot site is currently a single-family residence (see Figure 1-2, Existing Site Map). The topography of the site is characterized by relatively flat grades, grass lawns, and some trees and bushes. The drainage patterns are analyzed and discussed in further detail in the Level One Downstream Analysis (see Section 3.0). According to the King County Soil Survey, the site consists of Alderwood Soils, AmC, hydrologic soils group C. See Figure 1-1, Site Location Map, and Figure 1-2, Existing Site Map. 1.3 Post -Development Conditions The project proposes to develop an overflow parking lot for PowellsWood Garden. All surface water runoff is to be infiltrated in the existing soils. The site will be regraded and a vegetated permeable pavement parking lot constructed. Post -development surfacing will include 6700 ft2 of vegetated permeable paving, 1600 ft2 of interlocking pavers, 550 ft2 of asphalt pavement, and 1400 ft2 of gravel surfacing. Project improvements will reduce impervious surfaces by approximately 4500 ft2. The proposed developed site, including grading and drainage amenities, can be viewed on the Figure 1-3, Developed Site Map. Abbreviated Technical Information Report PowellsWood Garden Overflow Parking Lot 1-1 101MI30 2140097.10 1.4 Drainage Basins All onsite runoff is infiltrated onsite under the vegetated permeable paving and paver systems used to surface the parking lot and driveway areas. See Figure 1-3, Developed Site Map, for a visual representation. 1.5 Wetland Protection There are no wetlands to be protected during construction within the project vicinity. Abbreviated Technical Information Report M � a PowellsWood Garden Overflow Parking Lot 1-2 2140097.10 IM 01'L600bIZ ;ol 6uiVed MOLPano uapJeg pooMsIlOmOd :poda,d uoi;euUo;uj le�iugoal pa;einaaggy deW @4!S padolanaa""•'•• £-1 ainbi3 deW al!S 5ui4six3........ Z_1 ain5i3 deW uoilmol al!S"'""" i-i ain5i3 sa.in5i:j p•-g uoipaS LEGAL DESCRIPTION PER QUIT CLAIM DEED RECORDED UNDER RECORDING NUMBER 20121111IDDIOM THAT PMTI*H Or 'K "': wow-", QUARTER OF Tort sccwcm lowsw zp NOR w Me. ""c" =ffi I ukmy ROAD AND LYING 30UTH (w THE r&L10wI`4 DE_,C"m uwL BEGINNING AT A POIKI OF THE CAST LoX Ot THE ABOVE g$WjEED rARM NORTH MVig' EASI715.69 FEET FROM THE CENTER tM OF bMLTEly ROAD TO THE TRUE POINT OF OfGWNG OF THIS UHL' THENCE NORTH bnV41* WEST 220 M MORE OR LESS. TO THE WEST LINE OF 7W ABOVE DESC PARCEL AND END OF THIS LINE. VERTICAL DATUM NGYD2a CITY OF FEDERAL WAY VERTICAL BENCH MARK 2172-15--1 HE SIGNAL POLE BOLT AT SW QUAD OF 2ASTH ST AND PADFIC HIGHWAY. V�. ELE434.374' BASIS OF BEARING :1.01= STATE PLANE COORDINATE SYSTEM. NORTH ZONE CITY OF FEDERAL WAY HORIZONTAL CONTROL HOLDING CITY MONUMENT NUMBERS ilg AND 134. POINT NO. TIED M-12571524 E-127476457 I- VtoN Pn NTH TACK sk CAW AT THE INTEASECTION OF -DTH AVE SWTH W/ SOUTH Mm 5TRW, POINT NO. 13 N-13401&78 E.127 954.90 TACK IN CONCRETE IN CASE AT THE INlERSECllON OF 25TH AVE SOUTH W/ SOUTH 772ND STREET A LINE BETWEEN THE TWO FOUND MONUMENTS SEARS NORTH IV45'55 EAST, LEGEND 11 FOUND MONUMENT 11 SET HAIL AND WASHER SET REBAR AND CAP o FOUND PROPERTY CORNER BOLLARD MAIL BOX 51ON AS NOTED TEST PIT SANITARY SEMR CLEANOUT 0 SWARY SEWER MANHOLE 0 STORM CATCH BASIN m YARD GRAIN la GAS METER E— GUY ANCHOR -0- UTILITY POWER POLE 0 POWER METER FIRE HYDRANT IB HOSE 00 IRRGA7104 CONTROL VALVE WATER METER m WATER VALVE -1101 F-FIR. 11 LLY ti M-MADRONE. U-UNKNOWN UTILITY NOTES 1. SUWACe Ull MECAN MON P W-0 LOCATED ON %Fa:V 76- �FV:A - U y r THAT E C21AZefty DEPICTED HEREON. z ummotono =)v'vTIuTIlS SHOW HERZ.Ow ARI� BASED ON 0DIJBIN H.9Ix SURFACE EVIDENCE, MVjrT LOCATOR MARIONGS AND REOM DATA (SUCH AS A5-1RIYl OR un "Tymmm *Um'l) a_SHONN 4�ZES Or ARE NOT SHOWN. 3. ATNWDH LOCATIONS OF LINDEROR"D UTILITIES BASED ON UTUTY IOCATCA MARKINGS AMD ATCOKU DATA (SIX" AS AS --BUILT OR UTIUTY DISIdN 0RAWNGS) ARE OCOUDD RELIABLE. 7. INC. ASWUCZ N* LIABILITY FOR WE ACCURACY OF SAD DATA. 4. CALL 1-4100-424-5555 BEFORE ANY CONSTRUCTION EQUIPMENT USED 3' TOTAL STATION UlILI ONG STANDARD FIELD TRAVERSE 7 METHODS FOR CONTROL AND WAKING. RELIANCE NOTE THIS SURVEY WAS PREPARED AT THE REQUEST OF MON POWRL FOR THE SME AND EXCLOSVE USE OF MORI POWELL IhOM TI) RELY UPON Ahl% OR IrSE: THIS SURVEY DO NOT DaEND TQ MY 011HER PrY MOID-T THI IEIMSS FM=TUqtAT*N RY WEARPROFIESSMAL LAND RMI101 SURVICIrm OMOR STAW AND ScrATILQUE AIIIPLAR HEREON. SURVEYOR'S CERTIFICATE I, DAVID C- FOLLANSBEE, A PROfISSIONAIL LAND SURVEYOR IN WE WATE OF WASHINGITM HERINY CERTWV THAT THIS NAP COMC11.Y REPRESENIM A 5UNVrT MAIX By ME OR LNOCR My DIRECT SaNJRVISICIN N FEBRUARY 2014. AT THE REQUEST OF MONTE POWELL DAVID 0. FOILANSBEE, PL5 A$IM DATE POWELLSWOOD GARDEN A PORTION OF THE SE 1/4 OF THE SW 114 OF SEC. 05, TWN. 21 N., RGE. 04 E. W.M. CITY OF FEDERAL WAY, KING COUNTY, WASHINGTON. FOUND PIN IN CONCRETE IN CASE� Out mar CARPORT' ZA 41A 47t! ry TAL I aE 0 - jju qLa' CONCRETE PILLAR (TYP) STYD 1041 I!M*306-42 8' IRON E te-3m5D �A EE CKS APPNMWA,rE LOGAI)ON OF OUTFALL -4ap— II SiM 921 R(V•3MSC -v Cop I, rE.Z.&o HOUSE/GARAGE fto 1010-mMm PVC N-S IE-32L83 325 ki" rr wvm 6r A�r o,"c W7 [—LANDING S7, �0-- % CATE CCINTAOL: � Ak. w ClXavAw j % rwhD PIN IN crm"Z�� IN CASE-'-S 0"I 1 4, TEE POST o(*,C IE.3..:WFLECI FOuI0 PIN IN-\,jqj Lm� AS MASKER.... .. ... CONCRETE <m CASE J RIM-337.52 lE'm-s3m j%3 339 SOUTH DASH--CPOINT ROAD ssmH 547 W-3414o 11 Sim sm KIM N"So cDxj) NOT Onx 24- DOW K "nw-lz 20, cwc E Mob 24• cm"C R m-Aw.ba '0' W W IE_33LO CNp w Is Ws -DE COW lc'o.-Cwp LADOCIR IN E-334.04 I IMCN . 20 FT. -33 r- 7 L Amok, POI REBAAND C wim*mzwlAP 4 - t 341.59 TACOMA SEATTLE SPOKANII TRI-CITIES 2215 North 301h S.� S.b30D T--.WA98NO3 25LM32422M ZM-"-'k=FAX POWELLSWOOD GARDEN MONTE POWELL 430 SOUTH DASH POINT ROAD FEDERAL WAY, WASHKID3 214ODS7.50 I.... Set & Dote: FEBRUARY28,2014 4 1417111? 2=[=ZLh& Drawn by Checked b)G TAD DF f16 /-L OVERFLOW PARKING LOT, ADJACENT TO POWELLSWOOD GARDEN A PORTION OF THE SE 1/4 OF THE SW 1/4 OF SEC. 05, TWN. 21 N., RGE. 04 E. W.M. CONSTRUCTION NOTES FEDERAL WAY, KING COUNTY, WASHINGTON 1 PROVIDE TYPICAL PAVEMENT SECTION PER DETAIL CS 1 I 2 2 PROVIDE VEGETATED PERMEABLE GRASSPAVE PER DETAIL C31 3 PROVIDE VAN ACCESSIBLE ADA PARKING SIGN PER DETAILS C33 D 403 SOUTH DASH POINT ROAD . 1 PARCEL 0521049055 4 PROVIDE PAVER EDGE PER DETAIL G3.7 5 PROVIDE SLOPE ROUNDING PER DETAIL r . . C3.1 ,• 30102 4TH AVE SOUTH PROVIDE SAT TIE--INT OCAT ON PARCEL 0521049155 -,.• i�F . 6"MIN. COMPACTED CRUSHED ! SURFACING BASE COURSE " C3-2 C32 - .. •MIN. OCIMPACTEQ N 124710.37 V r CRUSHED SURFACING . '.'�'-j , .-' - •.• ._ -- .� E IZE0567-01 335 336 ` BASE CCU SE I + i r � • � I 337 .. a17� 33a �i I I iG:339A9 G: 3m 25 PAVERS (� f1YP.] N 124706.0 I t 7 l f_~o Y f_�A ft3c3%A0 1S E 1Z6%91at, %r,G I 1, 30112 4TH AVE SOUTH - § _ PARCEL 0521049012 � J S•0 5 STALLS 9'•Q' S LANDSCAPE PT: -26." "e• r PROVIDE ACCESSIBLE AppALy 8 STALLS �g'-0' 6' MAN GATE ) ROUTE TO BUILDING f - 9•Q' O ❑ p ENTRANCE jam! u D p D CS a p ' I f e.0' FG: Mn FG 335 - FG: 336.46 •- GATE CONTROL FG: 339.63 E ; CH E R5 0' (RELOCATED) . MATCH EX.� /MATCH EX. PARKING STALL MARKER (TYP.) {241ri5.' d� FG: 337.OD SEE LANDSCAPE PLAN E 12606DD.g9 }{f//J / J R73.e' I 4„ MIN. '-.. 1.... _..._.. _ _ +} o _. ( - - COMPACTED ` BUILDING • ` I S6 S t R29 0' CRUSHED OVERHANG VEGETATED a�IE BASE COURSE FCa-337,p R5.0' R40.0' { ♦^r�'�- I . 10 STALLS @ 9'-0" • g, TE MOTOR RELOCA7E0} N 124E49 0 E 12613513.16 _ N 124652 35 I FG: 337.3$ E 1269665 13 R25.0' 18' GARDEN GATE IRELOCATED) N.124663.31 _ �}[ N 124650 43 E 1269712.1141 _ N 12464529 PC-4.19AS L E 1269697-07 ` E 1269C564•% CHILDREN _ - - FG,33T.07 I (RELOCATED) 34 SY ENTRANCE GATE SEE LANDSCAPE PLAN FG: 337A2 PAVERS(TYP) - - - -- - FLt 337.38 2 'WIDE ASPHALT PAVEMENT DRIVEWAY FG: 33821 APRON .. - - MATCH ETC .. .... .. .. FOUND PIN IN COMCR ETE IN CASE •; • -••- ..,- .� .. - ..... FQ: 336.39` e_ � -._ ,. _ .. MATCH Ek MATCH EX, FG: 337.32 . MATCH EX. 3 N 124601.56 LOWER RIM AS NECESSARY TO E 126967fi.74 CREATE LOW POINT LOW POINT - - SOLIF71i DASI I fyo- I IN r AD LEGEND PERMIT NO.4 CITY OF FEDERAL WAY N \\ VEGETATED PERMEABLE PAVING PROPOSED CONTOUR —332 AKSL Fl04 •r7p Ty Q. ©Q©g MAIL ANO WA9HIR INTERLOCKING PAVER FINISH GRADE FG: 332� :11245e24389 E: 1269755 71 GRAPHIC SCALE f�I ELEV:336 60 CITY ENGINEER 0 5 FO 20 FEET ASPHALT PAVEMENT I I Know what's below. L-�� Call before loll dig. 1"=10 FEET CRUSHED SURFACING DATE 10[000 T A C 0 M A SEATTLE SPOKANE TRI-CITIES 2215 North 30th Street, Suite 300 Tacoma, WA 9W3 253.383.2422 TEL 253.363.2572 FAX www.ahbltom WEB ProiN•1 Ytr" OVERFLOW PARKING LOT, ADJACENT TO POWELLSWOOD GARDEN Client MONTE POWELL FEDERAL WAY, WA 96003 PHONE: (253) 839-4405 Job No 2140097.10 1s�s 5�C �olx. PERMIT SET MAY 2, 2014 C I AL 101[f Rw:aona• Sbee{ T,L� DEVELOPED SITE MAP Oos:enre by Drawn by: :a._2_1_. R JEFFRIES F KATONA D NASON ti I NQ FIGURE 1-3 4 of 6 Sheets 2.0 CONDITIONS AND REQUIREMENTS SUMMARY 2.1 Core Requirements 2.1.1 C.R. #1— Discharge at the Natural Location The project is not proposing to modify the existing drainage patterns on the site. 2.1.2 C.R. #2 — Offsite Analysis AHBL staff performed a Level One Downstream Analysis for the project. The analysis included: Defining and mapping the study area. Reviewing available information on the study area. • Field inspecting the study area. Analyzing the existing drainage system, including its existing and predicted problems, if any. Please refer to Section 3.0 for the full offsite analysis. 2.1.3 C.R. #3 — Flow Control The proposed parking lot will be constructed with permeable surfacing, and flow control will be achieved by infiltrating all of the parking lot runoff. Refer to Figure 4-1 for infiltration calculations. 2.1.4 C.R. #4 — Conveyance System There are no proposed conveyance systems as part of project development. Infiltration will occur by means of pervious pavers, vegetated permeable paving, and landscaped surfaces to the west of the existing house to remain. 2.1.5 C.R. #5 — Erosion and Sediment Control An erosion and sediment control plan has been developed for this site in accordance with the KCSWDM. The full erosion and sediment control plan is described further in Section 8.0 and in the project plans. 2.1.6 C.R. #6 — Maintenance and Operations The onsite drainage facilities will be privately maintained by the owner. 2.1.7 C.R. #7 — Financial Guarantees and Liability The owner will provide the necessary financial guarantees for permitting. Abbreviated Technical Information Report 13MI30 PowellsWood Garden Overflow Parking Lot 2-1 2140097.10 2.1.8 C.R. #8 — Water Quality The project site is subject to the Enhanced Basic Water Quality Treatment menu requirements per the City of Federal Way Water Qua/ityApplications Map. The goal of this treatment menu is to meet the requirements of the Basic Water Quality menu (reduce total suspended solids by 80% for a typical rainfall year) and to reduce zinc levels by 50%. According to Section 1.2.8.1 of the KCSWDM, the Enhanced Basic Water Quality menu may be reduced to the Basic Water Quality menu for treatment of any runoff that is infiltrated (see exception number 2). The proposed parking lot will infiltrate all stormwater runoff. Therefore, the Enhanced Basic Water Quality menu may be reduced to the Basic Water Quality menu. Refer to Section 4.0 for additional water quality facility information. 2.2 Special Requirements 2.2.1 S.R. #1— Other Adopted Area -Specific Requirements To our knowledge, no other adopted area -specific requirements apply to the project site. 2.2.2 S.R. #2 — Floodplain/Floodway Delineation The site is not located in a flood plain. 2.2.3 S.R. #3 — Flood Protection Facilities The project does not contain, will not construct, and is not adjacent to any existing flood protection facilities. 2.2.4 S.R. #4 — Source Controls The proposed project consists of a parking lot; therefore, it does not fit the definition of a commercial, industrial, or multi -family site for source control purposes. 2.2.5 S.R. #5 — Oil Control The project does not fit the definition of a high -use site; therefore, it is not subject to oil control requirements. Abbreviated Technical Information g Lo OM100 PowellsWood Garden Overflow ParkininLot 2-2 2140097.10 3.0 OFFSITE ANALYSIS 3.1 Level One Downstream Analysis The PowellsWood Garden site is located in the Easter Lake drainage basin in Federal Way. The drainage basin is approximately 152 acres in size. It includes Easter Lake, which has a water surface area of approximately 11 acres. The City of Federal Way has named the Easter Lake outlet system Cold Creek. The outlet system consists of enclosed pipes, ravines, and gullies that flow northwest from Easter Lake and ultimately discharge into Poverty Bay in the Puget Sound. Cold Creek passes by the northeast corner of the main PowellsWood Garden parcel (0521049055). Runoff that flows offsite from .the parking lot parcel flows northeast and onto the main PowellsWood Garden parcel. It is then conveyed to the northeast corner of the main PowellsWood Garden parcel by means of overland flow and a series of private culverts, catch basins, and enclosed conveyance pipes. At the northeast corner of the parcel, stormwater discharges into Cold Creek. The creek then flows northwest for approximately 1/2 mile before discharging into Poverty Bay. There are no known problems with the downstream drainage system. The parking lot site receives only a small amount of off -site runon from the South Dash Point Road right-of-way. This runon is generated by a narrow strip of vegetation located between an existing roadside ditch and the parking lot parcel south property line. The roadside ditch and conveyance system along the north side of South Dash Point Road collect and convey runoff from the road and direct it east, where it ultimately discharges into Cold Creek. Project improvements include grading a small berm at the south edge of the parking lot parcel in order to ensure that runoff from South Dash Point Road will not flow onto the site. A small portion of 4th Avenue South drains onto the parking lot site at the west boundary. Stormwater in this area sheet flows north off the site onto parcel 0521049155. Project improvements will reduce the amount of impervious surfaces in this area of the project. Therefore, parcels located north of the project will not be adversely affected by project improvements. The proposed parking lot has been designed to infiltrate all stormwater runoff into the underlying site soils (see Section 4.1 for more information). Runoff is not expected to leave the project site. In the unexpected case that stormwater runoff does in fact overflow from the site, it will be directed northeast towards the PowellsWood Garden site and Cold Creek. This runoff would follow the same downstream path to the Puget Sound that is described above. Project improvements include grading a small berm at the north edge of the parking lot as a measure of protecting parcel 0521049155 from receiving runon from the project site. Runoff from the project site does not flow onto public right-of-ways adjacent to the site in the existing condition, nor will it in the post -development condition. The City of Federal Way commissioned KCM to prepare a comprehensive surface water study for the City of Federal Way. Chapter 8 of the KCM report addresses the Easter Lake Drainage Basin. The City's consultants performed hydrologic and hydraulic modeling to determine the flows in Cold Creek near Dash Point Road. Their study determined that a 25-year flow, under existing land use and existing conditions, is 16 cubic feet per second, and the 100-year, 24-hour storm is 18 cubic feet per second. The City's consultant utilized a 24-hour event model to compute the peak flows for the design storm events. Abbreviated Technical Information Report 01003 PowellsWood Garden Overflow Parking Lot 3-1 2140097.10 The open channel portion of Cold Creek on the Powell property was surveyed at approximately 30-foot contour intervals. Based on this survey and topographic survey, the maximum channel slope is 6.2 percent. Utilizing this maximum slope, a channel section was designed that would carry the flow with a depth of 6.2 inches, and a channel bottom of 4 feet with 3-to-1 side slopes. The calculations from the City's comprehensive surface water report are enclosed, as are the channel dimension calculations. Abbreviated Technical Information Report PowellsWood Garden Overflow Parkin Lot 3-2 2140097.10 10MOM Section 3.0 Figures Figure 3-1 ........Level One Map Abbreviated Technical Information Report 0030 PowellsWood Garden Overflow Parking Lot 2140097.10 WAP 5437210130 7862740i60 7862700700 05270d9077 51521DO070 Lege W 5437213060 i862700790 18627OW90 _ ? } 5437210mo 5437210120 S2w"Pt. �7 r y 47 z7ao1a7 s � �! Gotmty Boundary Parcels 5437210040 1&2700210 3 5437210086 $437210110 1862100350 IW270DOSO W3'' Contours (sit light) Lakes and large Rivers 5437270070 186270D340 5752700ad0 D 5437210030 186270OD70 5152100160 Ss52140 5437210700 . 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King County makes no representations or warranties, express or implied. as to accuracy, completeness, timeliness, or rights to the use. of such information. This docunfant is not intended for Use as a survey product King County shall not be tlabte for any general, speclat, indirect, Incidental, or cons uenbal damages including. but not limited to, les-1 revenues or lost profits resulting from the use or misuse of the information contained on this map. Any sale of Ibis map or Information on this map Is prohibited except by written permission of King County. King County Date: 316/2014 Source: King County iMAP - Stormwater (hftp:ltwww.metrokc.gov/GIS/iMAP) 4.0 FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN 4.1 Flow Control The project site is located in a Conservation Flow Control Area per the City of Federal Way Flow Control Applications Map. There are no known downstream problems for the project site. Therefore, the site is subject to the Level 2 Flow Control standard per the KCSWDM. The project proposes to construct a vegetated permeable paving parking lot and a permeable interlocking concrete pavement (PICP) paver driveway. The proposed PICP system will be installed on an open -graded aggregate bedding course and consist of joints that are filled with permeable aggregates. Permeable paving surfaces are considered an LID practice. This project will utilize permeable paving surfaces that accommodate pedestrian, bicycle, and automobile traffic. The surfaces will also allow stormwater to infiltrate into the underlying soils, thus providing flow control and treatment. The KCSWDM provides limited design recommendations for permeable pavement and its use as a flow control facility. Therefore, the flow control system has been designed to meet the standards outlined in the Department of Ecology 2012 Stormwater Management Manual for Western Washington (SWMMWW). The applicable sections of the SWMMWWare 2.5.7Minimum Requirement #7: Flow Control of Volume land 3.3.7 Site Suitability Criteria (SSC) of Volume III. Both the parking lot and driveway surfaces will infiltrate all stormwater runoff. A design infiltration of six inches per hour was used to size the infiltration facilities. This rate is the recommendation provided in the Geotechnical Engineering Report (Figure 6-1). The SWMMWW flow control standard is actually exceeded because the parking lot and driveway infiltration facilities have been designed to infiltrate all stormwater runoff. No runoff is expected to discharge off the site. Refer to Figure 4-1 for Western Washington Hydrology Model version 2012 version (WWHM12) model output. 4.2 Water Quality System Pollution generating surfaces for the proposed site include the proposed parking lot and driveway. As mentioned in previous sections, these surfaces are subject to the Basic Water Quality menu requirements of the KCSWDM. The KCSWDM provides limited design standards for permeable pavement and its use as a water quality facility. Therefore, the water quality system has been designed to meet the standards outlined in the SWMMWW. The applicable sections of the SWMMWW are 2.5.6 Minimum Requirement #6: Runoff Treatment of Volume land 3.3.7 Site Suitability Criteria (SSC) of Volume III. The project site has underlying soils with a measured cation exchange capacity of 6.5 milli - equivalents per 100 grams of soil and an organic content of 1.60% (see Figure 6-1, Geotechnical Engineering Report). These capacities exceed the minimum requirements outlined in Section 3.3.7of the SWMMWWfor soils used for treatment. All site stormwater runoff will be infiltrated beneath the parking lot and driveway into the underlying soils. Therefore, the requirements of the SWMMWWwill be met. See Figure 4-1 for supporting calculations. Abbreviated Technical Information Report CIM133 PowellsWood Garden Overflow Parking Lot 4-1 2140097.10 Section 4.0 Figures Figure 4-1 ........PowellsWood Garden Storm Calculations Abbreviated Technical Information Report PowellsWood Garden Overflow Parking Lot MMMM 2140097.10 Powellswood Garden Storm Calculations Project: Overflow Parking Lot, Adjacent to Powellswood Garden Project Number: 2140097.10 Task: Permeable Pavement Calculations Date: 3-5-2014 Performed By: Ryan Jeffries, PE Design Criteria: Design storm treatment system such that 91% of total stormwater runoff is treated and that 100% of runoff is infiltrated during the 100-year event. Reference: King County Surface Water Design Manual, January 9, 2009 edition Software Used: The pervious pavement was sized and analyzed by using WWHM12 Model Schematic Schematic Ptedevelopea ■ v 0 " c-. :ems L ED / 4: 51' 4 , el--/ Permeable Pavement Sizing Eg:• Permeable Pavement 1 tAitigated ,�`^—.• ._ .. Facility Name Permeable Pavemeo T ovrrnstrearn Connection acility Type Outlet 1 Outlet 2 -- Outlet 3 PPetmeahle Paverrrei7t. _ - t uick Pavement f s Facility Dimension Diagram Facility Dimensions Pavement Length (ft) ly7 Pavement Bottom Width (ft) Effective Total Depth (ft) jv.87 Bottom slope (f0t) Effective volume Factor. Fo— Layers for Permeable Pavement Pavement Thickness (it) p� Pavement porosity {U-1) Sublayer 1 Thickness (fl) f3:os t7.I[i7 Sublayer 1 porosity (0.1) Sublayer 2 Thickness (R) Sublayer 2 porosity (0-1] Infiltration YES «� Measured Infr7tration Rate rwVhrl Reduction Factor jinfilt1aetm) Use%#etted SurfaceAtea (sidewallsJ Np Totalktolume infiltrated (ac•ft) 148,203 Total Volume Through Riser(ac-ft) 0 Size Pavement !`! Target %: 105 --H 4 Overflow Data Ponding Depth Above Pavement (ft) Oj0 Diameter Height (in) M Underdrain 0 �--;, Fp Storage Volume at Top of Pavement (aaftj -206. Show Pavement Table 10penTable Inifial Stage UO 0. Total Volume Through Fa,, ty ac• t 146.2©3 Percent Infiltrated 1013 An area equal to 1 acre is used for the modeling; the amount of area used is not relevant because the section is what determines performance. The permeable pavement system infiltrates the surface water at a rate of 6 in/hr into the existing soils as per the geotechnical engineers recommendation. The system's total thickness is 1.26' (manufacturer minimum recommendation) and the surface water infiltrates easily without getting into the top paver section. Water quality mitigation is provided by the existing subgrade soils in which the surface water runoff is to infiltrate because the soils meet the criteria for doing so as noted below. Acceptable groundwater protection is provided by the soil if the first two feet or more of the soil beneath the infiltration facility has a cation exchange capacity greater than 5 and an organic content greater than 0.5%, and meets the following criteria: The soil has a measured infiltration rate less than or equal to 9 inches per hour, and it must be composed of less than 25% gravel by weight with at least 75% of the soil passing the #4 sieve. The portion passing the #4 sieve must meet one of the following gradations: ■ At least 50% must pass the #40 sieve and at least 2% must pass the #100 sieve, or At least 25% must pass the #40 sieve and at least 5% must pass the #200 sieve. Note: The above soil properties must be met by the native soils onsite. Soil may not be imported in order to meet groundwater protection criteria without an approved adjustment. t�'i/! / i i 5.0 CONVEYANCE SYSTEM ANALYSIS AND DESIGN There are no proposed conveyance systems for this redevelopment. Abbreviated Technical Information Report 1518130 PowellsWood Garden Overflow Parking Lot 5-1 2140097.10 6.0 SPECIAL REPORTS AND STUDIES A Geotechnical Engineering Report from South Sound Geotechnical Consulting is provided as Figure 6-1. Abbreviated Technical Information Report PowellsWood Garden Overflow Parking Lot 2140097.10 6-1 Section 6.0 Figures Figure 6-1 ........Geotechnical Engineering Report South Sound Geotechnical Consulting Abbreviated Technical Information Report 13033 PowellsWood Garden Overflow Parking Lot 2140097.10 South Sound Geotechnical Consulting March 4, 2014 Powellswood Gardens c/o AHBL, Cnc. 2215 North 30"' Street, Suite 300 Tacoma, WA 98403-3350 Attention: Ms. Doreen Gavin, P.E. Subject: Geotechnical Engineering Report Infiltration Assessment Powellswood Gardens Overflow Parking Area Federal Way, Washington SSGC Project No. 14012 Dear Ms. Gavin: South Sound Geotechnical Consulting (SSGC) has completed our infiltration assessment for the planned parking area for Powellswood Gardens at 30.112 - 411 Avenue South in Federal Way, Washington. Our services have been completed in general conformance with our proposal (P14008, dated .February, 2014) and authorized by Mr. Monte Powell on the same day. The purpose of our services was to assess infiltration characteristics of native subgrade soils for pervious parking sections. Our scope of services included completing two Pilot Infiltration Tests (PIT), laboratory testing, engineering analyses, and preparation of this report. PROJECT INFORMATION The lot is bordered by Dash Point Road (Hwy 509) to the south, 4' Avenue South to the west, Powellswood Gardens to the east, and a residential lot to the north. The planned parking area is a residential lot with one home and several outbuildings (garagcs/shops). We understand plans include removal of the outbuildings and eastern portion of the residence, and converting most of the lot to overflow parking for :Powellswood Gardens. The GrassPave2 porous pavement system has been selected for the parking surface to assist in stormwater control. Vehicle traffic is assumed to consist of principally light vehicles (cars). We understand that finish parking surface grades will be near existing grades. SITE AND SUBSURFACE CONDITIONS The lot is relatively level with non -building areas principally landscaped as grass lawn with some deciduous and evergreen trees, and bushes. Subsurface conditions were assessed by observing three hand -dug excavations in the planned parking area on February 27, 2014. Two of these holes were used :for infiltration tests (IT-1 and IT-2) and were located in the eastern portion of the planned parking area. A third excavation, Pot Hole I (PH-1) was located in the western portion of the parking area to assess conformity of soils across the site. P.U. Box 39500, Lakewood, WA 98496 (253) 973-0515 / Geotechn.ical Engineering Report Powellswood Gardens Parking Area Federal Way, Washington SSGC Project No. 14012 March 4, 2014 SSGC Approximate locations of the excavations are shown on Figure 1 Site Plan. Observed soil conditions in the test holes are described below: Soil Conditions Infiltration Test I (1T-1): 0 - 0.25 feet: Sod and topsoil. 0.25 — 2.75 feet: Medium dense, moist, gray, gravelly SAND with trace silt and occasional cobble. Tnflt3ration Test 2 IT-2 0 -.0.83 feet 0 0 inches): Sod and topsoil. 0.83 — 1.5 feet: Medium dense, moist, may, gravelly SAND with trace silt and occasional cobble. Pot Hole 1 PIi-1 0 - 0.75 feet: Sod and topsoil. 0.75 — 1.5 feet: Medium dense, moist, brown, gravelly SAND with trace silt. In addition to the above described test .holes, two holes had been previously dug on the Powellswood Gardens lot, immediately east of the fence that separates the two properties. These .holes were on the order of 2.75 to 3 feet deep and soil conditions were similar to those observed in the test holes in the parking area. Groundwater Conditions Groundwater was not observed in the test holes at the time of our fieldwork on February 27, 2014. Surface grades drop moderately to the east and .north of the parking area. No evidence of seepage or other indications of shallow groundwater were observed on adjacent slopes. As such, we estimate that permanent groundwater levels below the planned parking area are on the order of 10 feet or deeper below surface grades. Geologic Setting Soils on the site have been surveyed and classified by the U.S. Soil Conservation Service. The report of this survey is presented in the "Soil Survey of King County Area, Washington", originally issued in 1973. This report indicates that surface soils on the site are mapped as Alderwood gravelly sandy loam. 2 Geotechnical Engineering Report Powellswood Gardens Parking Area Federal Way, Washington SSGC Project No, 14012 March 4, 2014 SSGC Alderwood gravelly sandy loam reportedly consists of moderately well drained soil that formed in glacial till. Native soils observed in the test holes at this site appeared to contain much less loam (silt) than typical glacial till soils in the area. Soils observed are considered to be more representative of glacial outwash or sandy glacial till. GEOTECHNICAL DESIGN CONSIDERATIONS Site soils and infiltration characteristics are considered suitable for the GrassPave2 porous pavement system. Recommendations presented in the following sections are based upon the subsurface conditions observed in the test holes and our current understanding of project plans. However, it should be noted that subsurface conditions across the site may vary from those observed and can change with time. Therefore, proper site preparation will depend upon the weather and soil conditions encountered at the time of construction. We recommend that SSGC review final plans and assess subgrade conditions for foundations at the time of construction. The native glacial gravelly sand will provide suitable support and infiltration for porous pavements. Pavement subgrades should consist of the native gravelly sand below the sod/topsoil layer. Infiltration Characteristics Two (2) Pilot Infiltration Tests (PIT) were performed in the planned parking area in general conformance with Section 3.3.6 of the 2012 Washington State Department of Ecology (DOE) Stormwater Management Manual , for Western Washington. These tests were completed at depths near the anticipated su.bgrade elevation of the porous pavement section. Results of the infiltration tests are presented in the table below. Infiltration Test Results Depth of Test Uncorrected (Field) Corrected Infiltration from surface Infiltration Rate Infiltration Rate Correction Factors* Test No. (inches) (in/hr) (Whr) {CFvICFt/CFtn) IT.] 20 12 4.3 (0.8/0.5/0.9) IT-2 18 24 8.6 (0.8/0.5/0.9) *Correction Factors from Table 3.3.1 of the 2012 DOE Stormwater Management Manual for Western Washington. Infiltration test site IT-] was advanced to a depth of I foot below the test elevation. Similar soils were observed to the completion depth. Also, as stated previously, two holes extending to a maximum depth of 3 feet on the eastern perimeter of the parking area indicated similar soils to at least that depth. The corrected infiltration rates of 4.3 to 8.6 inches per hour (in/hr) are considered appropriate for the soils observed. As soils in the two infiltration test holes and the pot hole appear similar, it is our opinion that these rates could be averaged for design purposes across the site. We recommend that an average Geotechn.i.cal Engineering Report Powellswood Gardens Parking Area Federal Way, Washington SSGC Project No. 14012 March 4, 2014 SSGC infiltration rate of 6 in/hr is used in design to account for soil variability. It is our opinion that groundwater .levels will not adversely impact infiltration below the porous pavement section. A Cation Exchange Capacity (CEC) and organic content test were completed on representative pavement subgrade soils. CEC and organic content results indicate the soils wilt generally satisfy DOE requirements. Test results are summarized in the following table. CEC and Organic Content Results Sample Test No. CEC Results CEC Required* Organic Content Organic Content and Depth (milliequivalents) (milliequivalents) Results (%) Required* {%} PT-1, 18 inches 6.5 > 5 1.50 >1.0 *Per Section 3.3.7 of the 2012 DOE Stormwater .Management Manual for Western Washington, Porous Pavement Subgrade Preparation We recommend that the sod/topsoil and any fill or other deleterious materials encountered during site preparation are removed from porous pavement areas. Subgrades should consist of the native gravelly sand. Stripping depths are anticipated to range from about 4 to 10 inches based on observed conditions in the test holes, but may be deeper in other areas across the site. Subgrade preparation guidelines for porous (pervious) pavements typically recommend limiting or eliminating compaction of subgrades so densi.fication and reduction of infiltration capacity will not occur. Subgrades in porous (pervious) pavement areas should not be proofrolled following stripping. Wheeled vehicles should not be allowed to drive over porous pavement Subgrades. Tracked equipment traffic should be limited to the extent possible. Porous pavement sections typically use a storage bed of free —draining imported granular material under the surface pavement section and above the prepared subgrade. The thickness of the storage layer should be sized for the amount of sormwater to be stored. Storage bed material should conform to the gradation criteria presented in Section 9-03.12(5) "Gravel Back -fill for Drywells" of the WSDOT Specifications for Road, Bridge, and Municipal Construction (Publication M 41-10), or as approved by the City of Federal Way. REPORT CONDITIONS This report has been prepared for the exclusive use of AHBL and Powellswood Garden for specific application to the project discussed and has been prepared in accordance with generally accepted geotechnical engineering practices in the area. No warranties, either express or implied, are intended or made. Site safety and earthwork construction procedures are the responsibility of others. In the event 4 Geotechnical .Engineering Report Powellswood Gardens Parking Area Federal Way, Washington SSGC Project No. 14012 March 4, 2014 SSGC that changes in the nature, design, or location of the project as outlined in this report are planned, the conclusions and recommendations contained in this report shall not be considered valid unless SSGC reviews the changes and either verifies or modifies the conclusions of this report in writing. The analysis and recommendations presented in this report are based on observed soil conditions in the test holes at the indicated location and from other information discussed. This report does not reflect variations that may occur between explorations, across the site, or due to the modifying effects of construction or weather. The nature and extent of such variations may not become evident until during or after construction. If variations appear, we should be immediately notified so that further evaluation and supplemental recommendations can be provided. The scope of services for this project does not include either specifically or by implication any environmental or biological (e.g., mold, fungi, bacteria) assessment of the site or identification or prevention of pollutants, hazardous materials or conditions. If the owner is concerned about the potential for such contamination or pollution, other studies should be undertaken. We appreciate the opportunity to work with you on this project. Please contact us if additional information is .required or we can be of further assistance. Respectfully, South Sound Geotechnical Consulting EL Ro 1 r� .N 1 Timothy H. Roberts, P.E., R.G. Member/Geotechnical Engineer Attachments: Figure 1: Site Plan Laboratory Results (CEC and Organic Tests) 5 i EE� J m S Q E b w C � m �i^ysl w 3 a C O UD c, _u 00 p- •LJ Ln Ol ilh! W X o M o rn u d Ln w o � o +.j O l� r t�U d O � _ D 4 W OJ m to x O x 0 OL CL a a C � ~® I d Z 0 2 V- ■ $ z © � _ u A _ u n $ ' 0 e � 0 $ $ w CD I490 40 a z o 0 cm § R a 2 $ 2 0 0 LO k � z t w 2 5 = k U 2 e \ � 2 @ - 2E )�{!N /& k k/§ )# o 0 LO ) { (& k {|&CL ƒ � )& E BE z :i ;I!% =a 2 t.£)§ i! ! k ) {& 2 } � }E ! § \E . CD /k} � ! / : 2 )E ƒ § _ ] k (k \ � kk a e £a , » = rA o 7.0 OTHER PERMITS No additional permits will be required for redevelopment of the site. Abbreviated Technical Information Report 101803 PowellsWood Garden Overflow Parking Lot 7-1 2140097.10 8.0 ESC ANALYSIS AND DESIGN The proposed development will comply with guidelines set forth in the 2009 KCSWDM. The plan includes erosion/sedimentation control features designed to prevent sediment -laden runoff from leaving the site or from adversely affecting critical water resources during construction. 8.1 ESC Plan Analysis and Design The erosion potential of the site is influenced by four major factors: soil characteristics, vegetative cover, topography, and climate. Erosion/sedimentation control is achieved by a combination of structural measures, cover measures, and construction practices that are tailored to fit the specific site. The following measures will be used to control sedimentation/erosion processes: • Clearing Limits: All areas to remain undisturbed during the construction of the plat will be delineated prior to any site clearing or grading. ■ Cover Measures: Disturbed areas shall be covered as required in Section D.4.2 of the KCSWDM. • Construction Entrances: A stabilized construction entrance consisting of quarry spalls will be placed at the entrances to the existing site and as necessary. • Perimeter Protection: Filter fabric fencing will be provided along the northern, eastern, and western perimeters to protect the sensitive wetland areas and to prevent sediment laden runoff migration. • Storm Drain Inlet Protection: Filter fabric protection will be provided on all new and existing catch basins downstream of construction activities. • Surface Water Control: Interceptor ditches will be used to direct runoff from construction areas to the sediment trap and pond. • Dust Control: Dust control measures will be implemented when exposed soils are dry to the point that wind transport is possible and roadways, drainage ways, or surface waters are likely to be impacted. A temporary sediment trap is not an appropriate BMP for the project for the following reasons: 1. given the site topography, the maximum tributary area for the trap would be insignificant (approximately 0.3 acres), 2. the excavated parking lot will serve as a temporary infiltration facility for potential runoff during construction, and 3. construction will occur during the dry season, which will minimize the potential for erosion. 8.2 Sensitive Area Restrictions There are no sensitive areas onsite. Abbreviated Technical Information Report PowellsWood Garden Overflow Parking Lot 8-1 [alums 2140097.10 8.3 ESC Maintenance All ESC measures shall be maintained and reviewed on a regular basis, as prescribed in the maintenance requirements of each BMP included in Figure 8-1 of this section. 8.3.1 ESC Supervisor The applicant shall designate an ESC supervisor who shall be responsible for maintenance and review of ESC and for compliance with all permit conditions relating to ESC. The ESC supervisor must be available for rapid response to ESC problems. The ESC supervisor shall review the site at least once a month during the dry season, weekly during the wet season, and within 24 hours of significant storms. The City may require that a written record of theses reviews be kept onsite with copies submitted to the City within 48 hours (also see section 8.3.3 below). The City may also require that the applicant designate an ESC supervisor with demonstrated expertise in ESC to perform these reviews and to be responsible for ESC due to the sensitive areas on or within the project site. The qualifications of such a person shall include at least several years of construction supervision or inspection and a background in geology, soil science, or agronomy. This role can typically be filled by the geotechnical consultant, wetland consultant, or design engineer. 8.3.2 Documentation If the City requires that a written record be maintained, all required maintenance reports shall be kept onsite throughout the duration of construction. Detailed maintenance requirements for each ESC measure are provided on the plans. 8.3.3 Review Timing During the wet season, weekly reviews shall be carried out every 6 to 8 calendar days. During the dry season, monthly reviews shall be carried out within 3 days of the calendar day for the last inspection (e.g., if an inspection occurred on June 6, then the next inspection must occur between July 3 and July 9). Reviews shall also take place within 24 hours of significant storms. In general, a significant storm is one with more than 0.5 inch of rain in 24 hours or less. Another indication that a storm is "significant" is if gullies form as a result of the runoff. Abbreviated Technical Information Report 13MOB PowellsWood Garden Overflow Parking Lot 8-2 2140097.10 9.0 BOND QUANTITIES, FACILITY SUMMARIES, AND DECLARATION OF COVENANT This section does not apply. Abbreviated Technical Information Report PowellsWood Garden Overflow Parking Lot 2140097.10 9-1 10.0 OPERATIONS AND MAINTENANCE PLAN The drainage facilities detailed in this report will be privately maintained. Abbreviated Technical Information Report MM130 PowellsWood Garden Overflow Parking Lot 10-1 2140097.10 11.0 CONCLUSION This site has been designed to meet the 2009 KCSWDM and as per the City of Federal Way addendum. The site incorporates infiltration facilities to mitigate stormwater on the site. Flow calculations/modeling utilized King County standards for sizing stormwater conveyance networks and treatment facilities. It was determined using these criteria that: Level 2 flow control is provided by the parking lot infiltration facility. Water quality is provided at the Basic Water Quality Treatment Level for the site. This analysis is based on data and records either supplied to or obtained by AHBL. These documents are referenced within the text of the analysis. The analysis has been prepared utilizing procedures and practices within the standard accepted practices of the industry. We conclude that this project, as schematically represented, will not create any new problems within the downstream drainage system. This project will not noticeably aggravate any existing downstream problems due to either water quality or quantity. AHBL, Inc. Lucas Johnson, PE, LEED AP Project Engineer LDJ/lsk May 2014 Q:\2014\2140097\10_QV\NON_CAD\REPORTS\TIR\Abbreviated_TIR. dooc Abbreviated Technical Information Report D PowellsWood Garden Overflow Parking Lot 11-1 2140097.10