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HomeMy WebLinkAboutStorm Drainage Report for GRD2014-00005 - GRD Engineering / Geo-Tech Reports - 5/23/2014 Engineering Services Associates, Inc. Friday, May 23, 2014 Loretta Swanson, PE Drainage Engineer Mason County Public Works 100 W Public Works DR, Shelton WA 98584 Subject: Taco Bell site re-development storm drainage planning and design. Dear Loretta, Taco Bell has entered into a land lease agreement with the Cady Family Trust and Mary Jo Cady in Belfair, WA to redevelop the property the Cady Family Trust and Mary Jo Cady own at the corner of Clifton Land and SR 3 in Belfair, WA. ESA Inc. has submitted for review the Civil Design Drawings and the Strom Drainage Report for the proposed Taco Bell re-development of the site. Note that the Cady Family Trust also owns the adjoining parcels to the west where the Reid Realty office and the storm water infiltration pond are located Our approach for the planning and design of the storm drainage control for the redevelopment of Taco Bell site is a follows: 1. We will store and infiltrate all the storm water from the re-development on site. To accomplish this objective we will pave the site with porous concrete pavement. 2. We will not be connecting the drainage system from the Taco Bell site to the existing or proposed WSDOT drainage system in SR 3. No review of our site plan is required by WSDOT for storm drainage entering onto state owned property. 3. We have designed the porous pavement section to store and infiltrate the onsite stormwater in accordance with the most recent edition of the WSDOE Stormwater Management Manual. We dug six— five foot deep - soil logs on the property in February of the 2014 and found the ground water to be between 36 and 42 inches below the surface of the ground. We have included a soil infiltration report prepared by Wnek Engineering with the Storm Water Report. 4. If there is overflow from the porous pavement onto the westerly portions of the Cady Family Trust property for any reason, then the stormwater will flow westerly across the Reid Realty parking lot to a catch basin that drains to a large, existing stormwater detention and infiltration pond. The existing infiltration pond was designed by Marley Young, PE to infiltrate the stormwater from the property that is being redeveloped. We chose not to rely on the existing pond to infiltrate stormwater from the redeveloped site because storm drainage design standards have changed since 2004 when the pond was designed and installed. We have included with this letter of introduction a recent aerial image of the site before the site was recently cleared for re-development. We have also included copies of Marley Young's Engineering Services Associates Inc. 210 N.E.Cherokee Beach, Belfair,Washington-98528 (360)275-7384 1 FAX(360)277-3187 Engineering Services Associates, Inc. reports for the planning and design of the existing stormwater infiltration pond. With regard to erosion control during construction- We will be constructing the project during June, July, and August of this year. We will be installing BMP's per the plan. We did not include a temporary erosion control basin in the erosion control plan because stormwater will not be leaving property owned by the Cady Family Trust. If silt laden water were to flow westerly from the redevelopment site across the Reid Realty site it will flow into the existing stormwater pond which has no outlet to area drainage. With regard to Maintenance of the onsite storm water facilities.- We have recommended to Peter Braun, the Taco Bell restaurant owner, that they vacuum sweep the porous concrete pavement as needed - but no less than twice a year. Yours Truly, Pat McCullough, PE Engineer of Record Taco Bell Project We are including photos of the porous concrete installed at Carl's Junior Hamburger site in Gig Harbor in 2013. I'r ;1 AIM Engineering Services Associates Inc. 210 N.E.Cherokee Beach,Belfair,Washington-88528 (360)275-7384 FAX(360)277-3187 Engineering Services Associates, Inc. li i Engineering Services Associates Inc. 210 N.E.Cherokee Beach,Belfair,Washington-98528 (360)275-7384 FAX(360)277-3187 Ol� REDEVELOPMENTA ,r °Z EXISTING DEVELOPMENT = DRAINAGE AREA- R °0 0.63 AC. 0.61 AC. ,err'''` � • t �� � � I W � r� r PRODUCE SALES OE I D REALTY a "t AZY W cl J o J o ERICS N z „ � z go . G� ` \ x Z o °° 1� 00�•� 41- • � t • A PROPOSED TACO BELL SITE SHOWING EXISTING CONDITIONS BEFORE THE SITE CLEARING WAS COMPLETED FOR REDEVELOPMENT GRAPHIC SCAic. (a MT) 1 ImE�.0 M1 Mason County Review Checklist For a Stormwater Plan Instructions: R`rT This checklist is intended to assist Staff in the review of a Stormwater Plan. The Stormwater Plan is reviewed for completeness with respect to the 2005 Department of Ecology Stormwater Manual. If an item is found to be not applicable, the Plan should explain the basis for the conclusion. The Plan is also reviewed for clarity and consistency. If the drawings, discussion, or recommendations are not understandable, they should be clarified. If they do not appear internally consistent or consistent with the application or observations on site, this needs to be corrected or explained. If resolution is not achieved with the author, staff should refer the case to the Planning Manager or Director. Applicant's Name: �d~mil -�� ( Z;2,a f n ^ L.11 lr-_ Zf�) /2yZ q , ©oevl Permit# !99V —ODOD$' Parcel#� �cr--r- - 0n00 Date(s) of the Document(s) reviewed: SECTION I-Construction SWPPP Narrative (1) Construction Stormwater Pollution Prevention Elements: (a) Describe how each of the Construction Stormwater Pollution Prevention Element has been addressed th gh the Construction S PPPyy OK? Comment: D,c &0f v��f f61� .�1�O�S- ��o, -,ass N j (b) Identify the type and location of BMP's usa�dd to satisfy the required element. '04 OK? t__;__;6omment (c) Written justiTication identifying the reason an element is not applicable to the proposal. OK? Comment: (d) 12 Required Elements-Construction Stormwater Pollution Prevention Plan (1) Mark Clearing Limits. OK?_ Comment: (2) Establish Construction Access. OK? Comment: (3) Control FJpw Rates. OK? V Comment: (4) Install Se ' ent Controls. OK? Comment: (5) Stabilize S _ . OK? Comment: (6) Protect Slo s. 1 OK?Comment: ND ��/'�� �/ 4 ��Q (7) Protect Dpm Inlets. OK? omment: (8) Stabilize Channels and Outlets. OK? Comment: (9) Control P lutants. OK? P Comment: (10)Control 9.pWatering. ..'' // OK? Comment: A/0 9 4t u ireCf' (11)Maintain P's. OK? V Comment: (12)Manage the Project. OK? J� Comment: fi2!�r/) 1��' Page 1 Form Effective May 2009 (2) Project Description. (a) Total project ea(acres/square feet). OK? omment A5'-P'4 ri''-4 D, G 3 (b) Total Proposd impervious area (acres/square feet). OK? /-*- Comment (c)Total prop area to be distu bed, inc ded off- ite borrow and fill areas (acres/square feet). OK? Comment: z". �CT. .y"4', (d)Total volumes f proposed cut and fill (cubic ards). / �- OK? Comment: ��tLRKe,4Yd/ (3) Existing Site Conditions. (a) Description pf the existing topography. OK? V Comment: (b) Descripti9i],0 the existing vegelation. / OK? Comment: X�Co /.� /`�Aow /�� (c) Descriptio the existing drainage. , ,S�uc>�, t-ri OK? Comment: .Al 74 >l'Clr/ lzew (4)Adjacent Areas. (1) Description of adjacent areas which may be affected by the site disturbance (a) Streams OK?_� omment: (b) Lakes / / OK? Comment: A (c)Wetlands ``// OK? Comment: /v~ (d) Residential Areas OK? Comment: (e) Roads � 4n�' 4 uj �file OK? Comment: ,�,�� CJ�l�'Cd/`149� (f) Other OK? Comment: (II) Description of the downstream drainage path ading from the site to the receiving body of water (minimum istance of 400 a s). ©=*WX `�� Ltd Y OK? Comment: O �` (5) Critical Areas: (a) Description f critical areas that re on or adjacent to the site. OK? Comment: e (b) Descrip!io�special require nts for working in or near critical areas. OK? V Comment: O'fGe (6) Soils: Description of on-site soils. (a) Soil name // L OK? l� .Z'Comment: d/Ar, z, �2'DYf i�OvT' (b) Soil mapping unit OK? Comment: (c) Erodibility OK? Comment: (d) Settleability OK? C ment: OK? Comment: (f) Depth OK? Comment: (g) Texture OK?__Comment: jS •��dl" Page 2 IV Form Effective May 2009 !i (h) Soil Stru e OK? Comment: �a. 41,2,0 Y (7) Erosion Problem Areas. (a) De criptio potential erosion problems on site OK. V Comment: (8) Construction Phasing. (a) Constructi equence. c / L _ l /-_ / l , OK?�omment: �fG LcN�� >� L�Dat'SJ�✓' / 1 v` �"7 (b) Constructio hasing (if proposed). �`� OK? Comment: (9) Construction Schedule. I. Provide a posed construction schedul OK? Comment: 57Gcrw, II. Wet Season Construction Activities (a) Proposed w t season construction ap ivities. OK?Comment: AeLP2!-e_ (b) Proposed wet season constru��t�jpAn restraints for envirgnmentally sensitive/critical areas. OK?_Comment: ICIP— (10)Engineering Calculations. Provide design calculations. (a) Sediment P nds/Traps. OK? Comment: (b) Diversions.OK? Comment: (a) Waterways. OK? Comment: �'It-C. (b) Runoff/Sto water Detention Calculations. / - OK? V Comment -Cor-e (11)Operations and Maintenance (a). An operation and maintenance schedule shall be provided for all proposed stormwater facilities and BMPs, and the party(or parties) responsible for maintenance and operation shall be identified. An operation and maintenance (0&M) Declaration of Covenant will be required to cover all privately owned and maintained stormwater facilities. 0& M Declaration of Covenant forms are available at the Mason County Permit Assistance Center, 426 W. Cedar Street, Shelton, WA 98584. The proponent shall record a copy of the completed Declaration with the Mason County Auditors'office.A copy of the recorded document must be submitted to the Permit Assistance Center together with this completed Checklist. OK? Comment: SECTION II—Erosion and Sediment Control Plans (1) General. (a) Vicinity Map a OK?_Comment: ✓`!P� 1^��,�rLrll (b) Clearing and Grading Approval Block. OK?_/,,,' Comment: (c) Erosion and diment Control Notes. OK? Comment: (2) Site Plan. (a) Legal desc tion of subject property. OK? Comment: (b) North Arrow OK? Comment: Page 3 Form Effective May 2009 (c) Indicate b daries of existing vegetation, e.g. tree lines, pasture areas, etc. • OK?Comment: (d) Identify ano label areas of potential erosion problems. OK? Comment: ,&�,� (e) Identify any�on-site or adjacent syrface waters, critical areas and associated buffers. OK? t Comment: d�+( (f) Identify FEYA base flood bou�nPnes and Shoreline Management boundaries (if applicable). OK? Comment: A4A-ty (g) Show exist and proposed contours. OK? Comment: (h) Indicate�d3ainage basins and direction of flow for' dividual drainage areas. OK? V Comment: ::i (i) Label final grade contours and identify de eloped condition drainage basins. OK?_Z Comment: (j) Delineate as that are to be cleared and graded. OK? Comment: (k) Show all cpt"and fill slopes indicating top and bottom of slope catch lines. OK? V Comment: (3) Conveyance Systems. (a) Designate Jpcations for swales, interceptor trenches, or ditches. OK? Comment: (b) Show all to porary and permanent drainage pipes, ditches, or cut-off trenches. OK? Comment: (c) Provide minimum slope and cover for all temporary pipes or call out pipe inverts. OK? Comment: (d) Show gra es, dimensions, and direction of flow in all ditches, sw les, culverts, and pipes. OK? Comment: Cmr47`mvrs milli (e) Provide details for bypassing o -site runoff around disturbed areas. OK? V Comment: rn l (f) Indicate to tionsand outlets of any dewatering systems. OK? Comment (4) Location of Detention BMP's. (a) Identify locagpn of detention PIs. OK? Comment: (5) Erosion and Sediment Control Facilities. (a) Show the jpcabons of sedim n trap(s), pond(s), .and s ructures. OK? Comment: ?t3 Zl rr��/�i �La> '� (b) Dimension pond berm widths�nd inside and outside ppp nd slopes. OK? V Comment: ,�'ON/a ' (c) Indicate the ap/pond storage/required and the depth, length, and width dimensions. OK? omment: (d) Provide tyOcal section views through pond and outlet structure. OK? 1/ Comment: 1C1~ (e) Provide typical details of gravel cone and standpipe, and/or other filtering devices. OK?_Comment 64rg:Q (f) Detail stabilijation techniques or outlettinlet. OK? l/" Comment: (g) Detail con!5pUrestrictor device I9cafion and details. OK. Comment: (h) Specify mul and/or recomMjended cover of berms and slopes. OK? omment: I (i) Provide roSK specifications end detail for rock check dams. OK? Comment: _Al"V (j) Specify sgacing for rock check Xams as required. OK? V Comment: Page 4 Form Effective May 2009 (k) Provide fr9nt and side sections of typical rock check dams. OK? l/ Comment: (1) Indicate th_,g locations and prrovid de ails and specifications for silt fabric. OK? V Comment: (m) Locate tile(construction entrance and rovid etail. / OK? Y Comment: ,� i�@t L� z- /�fuNS (6) Detailed Drawings. (a) Any structural practices used that are not referenced in the Ecology Manual should be explained and illustra d with detailed drawings.OK? Comment: , C 3 C /9✓��lii �7 (7) Other Pollutant BMP's. G l C-r (a) Indicated on the site plan the location of BMP's to be used for the control of pollutants other than sediment, g. concrete wash water. OK? Comment: S C-e- A"/- chi Z (8) Monitoring Locations. (a) Indicate on the site plan the water quality sampling locations to be used for monitoring water quality on >6construction site, if ap livable. OK? V Comment: pl ica Are the Documents signed and stamped? Type and#of License: �roSS id1L� If not approved, what is the next action/recommendation for further action? Reviewed by on Time spent in review: SECOND REVIEW/ UPDATE: Reviewed by on Time spent in second review: THIRD REVIEW/ UPDATE: Reviewed by on Time spent in third review: Disclaimer: Mason County does not certify the quality of the work done in this Stormwater Plan. Page 5 Form Effective May 2009 PERMIT NO. Nr� MASON COUNTY DEPARTMENT OF COMMUNITY DEVELOPMENT * i BUILDING•PLANNING•FIRE MARSHAL WWW.CO.MASON.WA.US (360)427-9670 Shelton ext.352 Mason County Bldg. III,426 West Cedar Street (360)2754467 Belfair ext 352 l.Yil PO Box 279, Shelton,WA 98W4 (360)482-5269 Elma ext 352 LAND MODIFICATION PERMIT OWNER INFORMATION: CONTRACTOR INFORMATION: NAME: a.-le-har-d G11e-c NAME: 1-24f MAILING ADDRESS: •f rowwA&,dierry 11,�,1 MAILING ADDRESS: Z/omff G CITY: STATE:__ZIP: jga83 CITY: STATE:/+ZIP:VY-9 PHONE: 7jk-64B-4WaocCELL: PHONE: o-Z7s-T3f CELL: -Za4 -z3S4, EMAIL:A,&r a4 a ©r gh.rr f-,toady- C dopV EMAIL : L&I RE # — EXP._-.t PARCEL INFORMATION: �2 3 —•¢-r o� PARCEL NUMBER(12 DIGIT NUMBER) /- FIRE DISTRICT_ LEGAL DESCRIPTION(ABBREVIATED): W/ -00 SITE ADDRESS /SIB L�/i 44~ 4d oe CITY DIRECTIONS TO SITE ADDRESS — C/ IS PROPERTY WITHIN 200 FT: SALTWATER❑ LAKE ❑ RIVER/CREEK❑ POND❑ WETLAND❑ SEASONAL RUNOFF❑ STREAM ❑ DOES PROPERTY HAVE SLOPE(S)WITHIN 300 FT OF THE PROJECT-GREATER THAN 14% YES❑ NO� WILL TIMBER BE CUT AND SOLD IN PARCEL PREPARATION ? YES ❑ NO❑ TYPE OF JOB: EXCAVATION ❑ FILLING ❑ GRADING CUTTING ❑ OTHER ❑ TOTAL SIZE OF PARCEL Q-0?i CRE /SQ FT SIZE OF AREA TO BE EFFECTED e:D4 3 CRES Q FT ESTIMATED AMOUNTY OF CUBIC YARDS 00 DOES THE SITE HAVE SLOPES 14%OR GREATER ES❑ NOK DES WORK WBE SCOPE OF WORr-WCV"1q � C~,W ar"ff&faAZ(-- r e �" WILL FILL BE BROUGHT ON SITE? IF YES,SITE ADDRESS: lA D c.Y WILL EXCAVATED MATERIAL BETAKEN OFF SITE?IF YES,SITE ADDRESS: rv- .4 DOES FILL CONTAIN POTENTIAL HAZARDOUS MATERIALS? YES❑ NO HAS A SOILS REPORT BEEN COMPLETED ON SITE?IF YES,INCLUDE A COPY.—*/v ��sn YES❑ N WILL PROPSAL RESULT IN REDIRECTION OF ANY SURFACE WWATER RUNOFF? YES❑ NONZ_ WILL WORK ALTER WHERE STORMWATER OF GROUND WATER ENTERS OR EXISTS THE SITE? YES❑ NO WILL QUALITY,QUANTITY OR VELOCITY OF STORM/GROUND WATER BE ALTERED? YES❑ NOg-- WILL THE RUNOFF BE COLLETED/CONTROLLED BY INTERCEPTORS,CUILTAIN DRAINS OR OTHER DEVICES? YES❑ NO�-- WILL THE LAND BE REPLANTED UPON COMPLETION. —L-st�a/f c-0t0 0 or9kl YES WNO❑ WILL THE PROPOSAL RESULT IN SLOPES STEEPER THAN THOSE CURRENTLY ON SITE? YES❑ NO Q� IS THE SITE WITHIN 200 FT OF A DESIGNATED SHORELINE OR A WETLAND? YES❑ NO OWNER/BUILDER acknowledges submission of inaccurate information may result in a stop work order or permit revocation. Acknowledgement of such is by signature below. I declare that I am the owner,owners legal representative,or contractor. I further declare that I am entitled to receive this permit and to do the work as proposed. I have obtained permission from all the necessary parties, including any easement holder or parties of interest regarding this project.The owner or authorized agent represents that the information provided is accurate and grants employees of Mason County access to the above described property and structure(s)for review and inspection.This permit/application becomes null&void if work or authorized construction is not commenced within 180 days or if construction work is suspended for a period of 180 days.PROOF OF CONTINUATION OF WORK IS BY MEANS OF INSPE CACT OF IS PERMIT APPLICATION OF 190 DAYS WILL INVAU TE T E APPUCATION. X Cat/ ;� S�? /¢— Signature of ApplicfinJ, Date x �Q� u//pyQGf� / i OWNER I PRESENTATIVONTRACTOR Print Name ( CATE) Storm Drainage Report Project Name: TACO BELL SEC 29,TWP 23 N,RGE 1 W,W.M. Assessor's Account No's: 1232941-00080& 123-41-00081 MASON COUNTY,WASHINGTON Proponent: Peter Bruan Orchard Group LLC 4550 NW Newberry Hill Silverdale, WA 98383 Ph. (360) 620-5500 Project Engineer: Pat McCullough, P.E. ESA Engineering, Inc. NE 210 Cherokee Beach Road Belfair, WA. 98528 Ph. (360)275-7384 Email: path@wavecablecom May 21, 2014 Mc W �a�� IONAL�U TABLE OF CONTENTS SECTION PAGE 1.0 PROJECT LOCATION& VICINITY ....................................................... 2 2.0 PROJECT DESCRIPTION.......................................................................2 3.0 EXISTING CONDITIONS......................................................................3 4.0 DEVELOPED SITE DRAINAGE CONDITIONS...........................................3-5 5.0 DRAINAGE BASIN DESCRIPTION.........................................................6 6.0 DESCRIPTION OF UPSTREAM BASINS...................................................6 7.0 DOWNSTREAM ANALYSIS...................................................................6 8.0 SOILS REPORT...................................................................................7 9.0 HYDROLOGICAL ANALYSIS................................................................ 8-31 10.0 EROSION AND SEDIMENT CONTROL....................................................31 APPENDIX APPENDIX A Wnek Infiltration Report..............................................................32 Page 1 1. PROJECT LOCATION & VICINITY MAP The site is located on the southwest corner of the intersection of Highway 3 &NE Clifton Lane (See Figure 1 —Vicinity Map). BELFAIR J T PROJECT LOCATION To Cr 0 300 7 iF' Oct ® Q FIGURE 1: VICINITY MAP 2. PROJECT DESCRIPTION The proponent is applying for a Mason County permit to develop a Taco Bell restaurant at the corner of Highway 3 and NE Clifton Lane. The project will include the restaurant, parking lot, drive-thru lane, ingress& egress to Highway 3 and NE Clifton Lane, along with water, sewer, storm drainage,and utilities. The site includes two parcels with a total site area of 0.63 acres. The tax parcel numbers are 12329-41-00080 and 1232941-00081 with the following legal description: LEGAL DESCRIPTION: PARCEL NO. 12329-41-00080(SEE QUIT CLAIM DEED AUDITOR'S FILE NO. 1975143) ALL THAT PORTION OF THE NORTHEAST QUARTER OF THE SOUTHEAST QUARTER OF SECTION 29, TOWNSHIP 23 NORTH,RANGE 1 WEST,W.M.,PARTICULARLY DESCRIBED AS FOLLOWS: BEGINNING AT A POINT NORTH 0°52'WEST,783.50 FEET AND NORTH 88°18'EAST,539.20 FEET FROM THE SOUTHWEST CORNER OF SAID NORTHEAST QUARTER OF THE SOUTHEAST QUARTER(WHICH IS MARKED BY AN IRON POST DRIVEN 10 INCHES BELOW THE SURFACE);THENCE NORTH 88'18'EAST, 145 FEET TO THE SOUTHWESTERLY MARGIN OF THE"OLD COUNTY ROAD TO ALLYN"AS IT EXISTED ON JANUARY 13, 1953;THENCE SOUTH 32°EAST,ALONG SAID MARGIN, 130 FEET TO THE NORTHWESTERLY RIGHT OF WAY LINE OF STATE ROUTE 3;THENCE SOUTH 63°37'WEST,ALONG SAID NORTHWESTERLY RIGHT OF WAY LINE,235 FEET;THENCE NORTH 0152'WEST,210.40 FEET TO THE POINT OF BEGINNING. EXCEPTING THEREFROM,ALL THAT PORTION THEREOF WHICH LIES WESTERLY OF THE EASTERLY LINE OF A TRACT OF LAND PARTICULARLY DESCRIBED AS FOLLOWS: BEGINNING AT A POINT NORTH 88°18'EAST,614.2 FEET FROM A POINT ON THE WEST LINE OF SAID NORTHEAST QUARTER OF THE SOUTHEAST QUARTER,NORTH 0°52'WEST,783.5 FEET FROM ITS SOUTHWEST CORNER;THENCE SOUTHERLY ALONG THE EASTERLY LINE OF A TRACT OF LAND CONVEYED TO JIM R.CADY IN DEED RECORDED UNDER AUDITOR'S FILE NO. 196035,TO THE NORTHERLY LINE OF STATE ROUTE 3;THENCE NORTHEASTERLY,ALONG SAID NORTHERLY LINE,30 FEET;THENCE NORTHWESTERLY,TO THE POINT OF BEGINNING. EXCEPTING THEREFROM RIGHT OF WAY FOR CLIFTON LANE,COUNTY ROAD NO. 86750. PARCEL NO. 12329-41-00081 RESULTING PARCEL 3 OF BOUNDARY LINE ADJUSTMENT NO.04-37, AUDITOR'S FILE NO'S 1814989 AND 1814990,RECORDS OF MASON COUNTY, WASHINGTON. TOGETHER WITH AND SUBJECT TO EASEMENTS,RESTRICTIONS AND RESERVATIONS OF RECORD. 3. EXISTING CONDITIONS The topography of the site is fairly flat, sloping south to southwest around 4%. The site is cleared of trees and brush with the exception of a small area along the north property line. The site includes crushed rock, concrete and asphalt from previous businesses. It also has an 8-inch water pipe traveling through the property along with a temporary power pole from the previous business owner. The land abutting the property includes an apartment to the north, real estate company to the west, Highway 3 to the south and NE Clifton Lane to the east. The site contains no critical areas with soils classified as sand and sandy loam. There are no existing natural or manmade drainage facilities on the site(See Figure 2 -Existing Site). 4. DEVELOPED SITE DRAINAGE CONDITIONS The land cover from the proposed project will include the proposed building, porous concrete parking lot, drive-thru lane, and landscape. The proposed stormwater design will include porous concrete pavement with clean drainage rock designed to support the pavement section along with storing storm water to infiltrate into the existing soils. The existing soils were tested for infiltration rates and Cation Exchange Capacity (CEC) per Washington State's Department of Ecology's stormwater manual. The infiltration rates varied from around 0.5 inches per hour along Highway 3 to 10 inches per hour further north. The infiltration rates along Highway 3 were low due to traffic compacting the area with the previous businesses. Therefore,the subgrade was designed to spread the stormwater out as much as possible to take advantage of the soils that have not been compacted. The subgrade will also be scarified to loosen up the subgrade prior to placing the pavement section. The pavement design will also include and emergency overflow pipe that will discharge stormwater west of the site(See Figure 3 - Proposed Drainage Areas). IYOLIN � � n EXISTING SITE ► ```�-A p I y� EXISTING SITE LW ;� Z r Of SO GRAMC sc a r �rsr� 1 W N Il FIGURE 2: EXISTING TOPOGRAPHY Page 4 rc>?^us a ', IN'A •r-�r y c •r• ri I .�. ` �•Sly I ' \ I Cg SIDChA_c Vr! t 1 v;FURi. 111133!!WAv sry„. i DESIGN CRITERIA FOR STORMWATER CALCULATIONS ca5 N A o Jd A �_ CRAM11C. KAIX ©'� JSOA S::I CL ASS•-CAI�C% i GW SAS: C._SG. N L:RA ON RAl nORCLS PAV=ME\• AREA Sr PAV-'Y?t' GRAVIF 7--:C(%'SS ® HAS\ C.'a AC7f5 uS:A SO: CIANO1 A':CV SAY,' D-S 7 1'_IRA!I^.A -M I = '.5 %/1IR -Mij% AY"Vc\' AR-A 7!5) 5' YAVIYLN ;:@AY•I. 'M'C<M1:SS - :7!%C-t:S ?'S\ C ,t7 ACRES ❑ uS'A 51), MASS:'-I" CAW SAY: NS.".\ 1W.-RA*IC\ WF '.5 ',/!IR �C7R.gI:S,AV Y 1' AR A 7'd1 S FIGURE 3: PROPOSED DRAINAGE AREAS Page 5 5. DRAINAGE BASIN DESCRIPTION The site was analyzed as three separate drainage basins. The basin areas are shown in Figure 3. The roof drainage from the proposed building will infiltrate within Basin A under the porous pavement section. The design of the drainage rock thickness will include the pavement area along with any tributary area draining to pavement. 6. DESCRIPTION OF UPSTREAM BASINS Upstream drainage areas are shown in Figure 3. The site will not receive stormwater from NE Clifton Lane as there is an existing curb & gutter along the south side of the street. The area shown along Highway 3 is the area from the future back of sidewalk once the State completes their highway improvements. 7. DOWNSTREAM ANALYSIS Stormwater from the developed site will infiltration into the existing soils. Therefore,there is no stormwater discharge from the developed site. The drainage system is designed with multiple drainage areas underneath the porous pavement to allow stormwater to infiltration into the existing soils. If one area exceeds its capacity, stormwater will overtop the seepage barrier beneath the porous pavement to the next drainage basin. The lowest basin in the system is the porous pavement just west of the parking area near the Highway 3 entrance. If this system exceeds its capacity,the system has an emergency overflow just west of the site; storm water will bubble up out of a catch basin within the existing parking lot(See Figure 4 -USGS Map). (30 r -y«_ , 1. • L 4 �-^ gel alY' 1 FIGURE 4: USGS MAP Page 6 8. SOILS REPORT Soil testing was completed to determine the infiltration rates and Cation Exchange Capacity (CEC). Five percolation tests were completed by Wnek Engineering and their report is included in the appendix. The soils are good for infiltration with USDA Soil P PP Classification of sand for test pit# I and loamy sand for test pit#4&5. With these soil texture classes, infiltration rates typically are 4-20 inches per hour as shown in Table 1. The infiltration rates are much lower near Highway 3 due to the vehicular traffic compacting the existing soils over the years. As you move away from the highway,the infiltration rates are more typical of what you would expect with these soil classes. A design infiltration rate of 1.5 inches per hour was used for this parking lot design. To achieve this rate,the subgrade material around test pit#1 will be scarified to a depth of 24- inches and compacted to 92%maximum dry density (MDD)per ASTM D 1557 or ASSHTO T180. With this compaction rate,the infiltration rates should be closer to the rates shown in Table 1. The rest of the pavement area will have the subgrade scarified to a depth of 12-inches and compacted to 92%MDD. This includes the area around test pit# 5 that shows an infiltration rate of 0.48 inches per hour. This drainage area is connected to the area near test pit#3 which showed an infiltration rate of 10.7 inches per hour. Stormwater will spread out within the drainage rock to take advantage of soils that have the higher infiltration rate. With a design infiltration rate of 1.5 inches per hour and the existing soils scarified, we expect to get infiltration rates around 3 to 4 inches per hour. At those rates the design rate would have a safety factor of 2 to 2.7 which is a reasonable long term safety factor for the project. Table 1 INFILTRATION RATES BASED ON USDA SOIL CLASSIFICATION Table 5-4 SOIL INFILTRATIONBASED ON 1. Gravel coarse sand 1 min/inch 2. Sand 5 min/inch 3. Loamv sand 15 min/inch 4. Sand loam 30 min/inch 5. Loam Unsuitable 9. HYDROLOGIC ANALYSIS Runoff computations utilized the Department of Ecology Western Washington Hydrology Model, 2012. Design parameters were as follows: 1. Area Mitigated—Both parcels, 0.63 acres. 2. Water Quality Mitigation —Through low impact development with the use of porous concrete pavement. The WA DOE stormwater manual requires the existing soils have a CEC greater than 5 meq/100g. The soils were tested and the CEC values were 9.5-15 meq/100g. 3. Water Quantity Mitigation—Water quantity mitigation will be through infiltration under the porous pavement. The pavement will be design to infiltrate 100%of the developed stormwater. WWHN2012 PROJECT REPORT Project Name: Tacobell Site Name: Taco Bell Site Address: City : Belfair Report Date: 5/21/2014 Gage : Quilcene Data Start : 1955/10/01 Data End : 2008/09/30 Precip Scale: 1.22 Version : 2013/06/26 Low Flow Threshold for POC 1 50 Percent of the 2 Year High Flow Threshold for POC 1: 50 year Low Flow Threshold for POC 2 : 50 Percent of the 2 Year High Flow Threshold for POC 2: 50 year Low Flow Threshold for POC 3 : 50 Percent of the 2 Year High Flow Threshold for POC 3: 50 year PREDEVELOPED LAND USE tic'-` Name : Basin A Bypass: No Groundwater: No Pervious Land Use Acres C, Forest, Flat .38 Pervious Total 0.38 Impervious Land Use Acres Impervious Total 0 Basin Total 0.38 Element Flows To: Surface Interflow Groundwater Name Basin B Bypass: No Groundwater: No Pervious Land Use Acres C, Forest, Flat .16 Pervious Total 0.16 Impervious Land Use Acres Impervious Total 0 Basin Total 0.16 Element Flows To: Surface Interflow Groundwater Name Basin C Bypass: No Groundwater: No Pervious Land Use Acres C, Forest, Flat .17 Pervious Total 0.17 Impervious Land Use Acres Impervious Total 0 Basin Total 0.17 Element Flows To: Surface Interflow Groundwater MITIGATED LAND USE Name : Basin A Bypass: No GroundWater: No Pervious Land Use Acres C, Forest, Steep .1 Pervious Total 0.1 Impervious Land Use Acres DRIVEWAYS FLAT 0.28 Impervious Total 0.28 Basin Total 0.38 Element Flows To: Surface Interflow Groundwater Gravel Trench Bed A Gravel Trench Bed A Name : Gravel Trench Bed A Bottom Length: 100.00 ft. Bottom Width: 78.00 ft. Trench bottom slope 1: 0.0001 To 1 Trench Left side slope 0: 0 To 1 Trench right side slope 2: 0 To 1 Material thickness of first layer: 0.5 Pour Space of material for first layer: 0.33 Material thickness of second layer: 0 Pour Space of material for second layer: 0 Material thickness of third layer: 0 Pour Space of material for third layer: 0 Infiltration On Infiltration rate: 1.5 Infiltration safety factor: 1 Discharge Structure Riser Height: 0.5 ft. Riser Diameter: 10 in. Element Flows To: Outlet 1 Outlet 2 Gravel Trench Bed Hydraulic Table Stage(ft) Area(ac) yolume(ac-ft) Discharge(cfs) Infilt(cfs) 0.0000 0.179 0.000 0.000 0.000 0.0167 0.179 0.001 0.000 0.270 0.0333 0.179 0.002 0.000 0.270 0.0500 0.179 0.003 0.000 0.270 0.0667 0.179 0.003 0.000 0.270 0.0833 0.179 0.004 0.000 0.270 0.1000 0.179 0.005 0.000 0.270 0.1167 0.179 0.006 0.000 0.270 0.1333 0.179 0.007 0.000 0.270 0.1500 0.179 0.008 0.000 0.270 0.1667 0.179 0.009 0.000 0.270 0.1833 0.179 0.010 0.000 0.270 0.2000 0.179 0.011 0.000 0.270 0.2167 0.179 0.012 0.000 0.270 0.2333 0.179 0.013 0.000 0.270 0.2500 0.179 0.014 0.000 0.270 0.2667 0.179 0.015 0.000 0.270 0.2833 0.179 0.016 0.000 0.270 0.3000 0.179 0.017 0.000 0.270 0.3167 0.179 0.018 0.000 0.270 0.3333 0.179 0.019 0.000 0.270 0.3500 0.179 0.020 0.000 0.270 0.3667 0.179 0.021 0.000 0.270 0.3833 0.179 0.022 0.000 0.270 0.4000 0.179 0.023 0.000 0.270 0.4167 0.179 0.024 0.000 0.270 0.4333 0.179 0.025 0.000 0.270 0.4500 0.179 0.026 0.000 0.270 0.4667 0.179 0.027 0.000 0.270 0.4833 0.179 0.028 0.000 0.270 0.5000 0.179 0.029 0.000 0.270 0.5167 0.179 0.032 0.017 0.270 0.5333 0.179 0.035 0.049 0.270 0.5500 0.179 0.038 0.090 0.270 0.5667 0.179 0.041 0.139 0.270 0.5833 0.179 0.044 0.195 0.270 0.6000 0.179 0.047 0.256 0.270 0.6167 0.179 0.050 0.323 0.270 0.6333 0.179 0.053 0.395 0.270 0.6500 0.179 0.056 0.471 0.270 Page 11 0.6667 0.179 0.059 0.552 0.270 0.6833 0.179 0.062 0.637 0.270 0.7000 0.179 0.065 0.725 0.270 0.7167 0.179 0.068 0.818 0.270 0.7333 0.179 0.071 0.914 0.270 0.7500 0.179 0.074 1.014 0.270 0.7667 0.179 0.077 1.117 0.270 0.7833 0.179 0.080 1.224 0.270 0.8000 0.179 0.083 1.333 0.270 0.8167 0.179 0.086 1.446 0.270 0.8333 0.179 0.089 1.561 0.270 0.8500 0.179 0.092 1.680 0.270 0.8667 0.179 0.095 1.801 0.270 0.8833 0.179 0.098 1.926 0.270 0.9000 0.179 0.101 2.053 0.270 0.9167 0.179 0.104 2.182 0.270 0.9333 0.179 0.107 2.315 0.270 0.9500 0.179 0.110 2.449 0.270 0.9667 0.179 0.113 2.587 0.270 0.9833 0.179 0.116 2.727 0.270 1.0000 0.179 0.119 2.869 0.270 1.0167 0.179 0.122 3.014 0.270 1.0333 0.179 0.125 3.161 0.270 1.0500 0.179 0.128 3.310 0.270 1.0667 0.179 0.131 3.462 0.270 1.0833 0.179 0.134 3.615 0.270 1.1000 0.179 0.137 3.771 0.270 1.1167 0.179 0.140 3.930 0.270 1.1333 0.179 0.143 4.090 0.270 1.1500 0.179 0.145 4.253 0.270 1.1667 0.179 0.148 4.417 0.270 1.1833 0.179 0.151 4.584 0.270 1.2000 0.179 0.154 4.753 0.270 1.2167 0.179 0.157 4.923 0.270 1.2333 0.179 0.160 5.096 0.270 1.2500 0.179 0.163 5.271 0.270 1.2667 0.179 0.166 5.448 0.270 1.2833 0.179 0.169 5.626 0.270 1.3000 0.179 0.172 5.807 0.270 1.3167 0.179 0.175 5.989 0.270 1.3333 0.179 0.178 6.173 0.270 1.3500 0.179 0.181 6.360 0.270 1.3667 0.179 0.184 6.548 0.270 1.3833 0.179 0.187 6.737 0.270 1.4000 0.179 0.190 6.929 0.270 1.4167 0.179 0.193 7.122 0.270 1.4333 0.179 0.196 7.317 0.270 1.4500 0.179 0.199 7.514 0.270 1.4667 0.179 0.202 7.713 0.270 1.4833 0.179 0.205 7.913 0.270 1.5000 0.179 0.208 8.115 0.270 Name Basin B Bypass: No GroundWater: No Pervious Land Use Acres A B, Lawn, Mod .08 Pervious Total 0.08 Impervious Land Use Acres DRIVEWAYS FLAT 0.08 Impervious Total 0.08 Basin Total 0.16 Element Flows To: Surface Interflow Groundwater Gravel Trench Bed B Gravel Trench Bed B Name : Gravel Trench Bed B Bottom Length: 100.00 ft. Bottom Width: 24.50 ft. Trench bottom slope 1: 0.0001 To 1 Trench Left side slope 0: 0 To 1 Trench right side slope 2: 0 To 1 Material thickness of first layer: 1 Pour Space of material for first layer: 0.333 Material thickness of second layer: 0 Pour Space of material for second layer: 0 Material thickness of third layer: 0 Pour Space of material for third layer: 0 Infiltration On Infiltration rate: 1 .5 Infiltration safety factor: 1 Discharge Structure Riser Height: 1 ft. Riser Diameter: 10 in. Element Flows To: Outlet 1 Outlet 2 Gravel Trench Bed Hydraulic Table _Stage(ft) Area(ac) volume(ac-ft) Discharge(cfs) Infilt(cfs) 0.0000 0.056 0.000 0.000 0.000 0.0222 0.056 0.000 0.000 0.085 0.0444 0.056 0.000 0.000 0.085 0.0667 0.056 0.001 0.000 0.085 0.0889 0.056 0.001 0.000 0.085 0.1111 0.056 0.002 0.000 0.085 0.1333 0.056 0.002 0.000 0.085 0.1556 0.056 0.002 0.000 0.085 0.1778 0.056 0.003 0.000 0.085 0.2000 0.056 0.003 0.000 0.085 0.2222 0.056 0.004 0.000 0.085 0.2444 0.056 0.004 0.000 0.085 0.2667 0.056 0.005 0.000 0.085 Page 13 S80'0 T91'E 6b0'0 9S0'0 EEES'T 980'0 996'Z 860'0 990'0 TTTS'T 980'0 6LL'Z L60'0 99010 688b'T 980'0 L89'Z 950'0 990'0 L99b'T 980'0 bOb'Z bWo 990'0 vvWT 980'0 9ZZ'Z Eb0'0 990'0 ZZZ6'T 1380'0 ESO'Z Zb0'0 990'0 00W T 980'0 b88'T Ob0'O 990'0 BLLE'T 980'0 OZL'T 6E0'0 990'0 999E'T 980'0 T9S'T 8£0'0 99010 EEEE'T S80'0 8W T LEO'O 990'0 TTTE'T 980'0 09Z'T S£0'0 99010 688Z'T 98010 LTT'T 6E0'0 990'0 L99Z'T 980'0 086'0 EEO'O 990'0 VVbZ'T S80'0 OS8'0 ZEO'0 990'0 ZZZZ'T S80'0 SZL'0 0£0'0 990'0 OOOZ'T 98010 809'0 6ZO'O 990'0 8LLT'T 980'0 LW O 8Z0'0 990'0 999T'T 980'0 96E'0 LZO'O 990'0 £E£T'T 980'0 OOE'0 SZO'O 9S0'0 TTTT'T S80'0 13TZ'0 6ZO'O 91;0'0 6880'T 980'0 6ET'O EZO'O 9S0'0 L990'T 980'0 9LO'O ZZO'O 9S0'0 b O'T S80'0 9Z0'0 OZ0'0 990'0 ZZZO'T 980'0 000'0 6TO'O 990'0 0000'T 980'0 00010 8T0'0 990'0 8LL6'0 98010 000'0 LTO'O 990'0 9996'0 S8010 000'0 LTO'0 9S0'0 EEE6'0 980'0 000'0 LTO'0 9S0'0 TTT6'0 980'0 000'0 910'0 990'0 6888'0 S80'0 000'0 9TO'O 990'0 L998'0 S80'0 000'0 STO'0 990'0 bb68'0 S80'0 000'0 STO'0 9S0'0 ZZZ8'0 S80'0 000'0 9TO'O 990'0 000810 980'0 000'0 6T0'0 990'0 BLLL'0 980'0 000'0 VTO'O 990'0 9SSL'0 980'0 00010 ETO'0 990'0 EEEL'O S80'0 000'0 £TO'0 990'0 TTTL'0 1380'0 00010 ZTO'O 990'0 6889'0 980'0 000'0 Z10'0 990'0 L999'0 1380'0 00010 ZTO'0 99010 V669'0 980'0 00010 TTO'O 990'0 ZZZ9'0 980'0 000'0 TTO'O 990'0 0009'0 980'0 000'0 OTO'O 9S0'0 8LLS'0 98010 000'0 OTO'O 99010 9999'0 980'0 000'0 OTO'O 990'0 E££910 98010 000'0 600'0 9S0'0 TTTS'O 980'0 000'0 600'0 9S0'0 68W O 1380'0 00010 80010 990'0 L99V'0 980'0 000'0 800'0 990'0 V6W o 980'0 00010 L00'0 990'0 ZZZ6'0 980'0 000'0 L00'0 9S0'0 0006'0 980'0 00010 L00'O 9S0'0 BLLE'0 980'0 000'0 900'0 990'0 99SE'0 980'0 00010 900'0 99010 EE£E10 980'0 00010 S00'0 990'0 TTT£'O 980'0 000'0 900'0 990'0 688Z'0 1.5556 0.056 0.050 3.360 0.085 1.5778 0.056 0.052 3.564 0.085 1.6000 0.056 0.053 3.771 0.085 1.6222 0.056 0.054 3.983 0.085 1.6444 0.056 0.055 4.198 0.085 1.6667 0.056 0.057 4.417 0.085 1.6889 0.056 0.058 4.640 0.085 1.7111 0.056 0.059 4.866 0.085 1.7333 0.056 0.060 5.096 0.085 1.7556 0.056 0.062 5.330 0.085 1.7778 0.056 0.063 5.566 0.085 1.8000 0.056 0.064 5.807 0.085 1.8222 0.056 0.065 6.050 0.085 1.8444 0.056 0.067 6.297 0.085 1.8667 0.056 0.068 6.548 0.085 1.8889 0.056 0.069 6.801 0.085 1.9111 0.056 0.070 7.058 0.085 1.9333 0.056 0.072 7.317 0.085 1.9556 0.056 0.073 7.580 0.085 1.9778 0.056 0.074 7.846 0.085 2.0000 0.056 0.075 8.115 0.085 Name Basin C Bypass: No Groundwater: No Pervious Land Use Acres A B, Lawn, Steep .05 Pervious Total 0.05 Impervious Land Use Acres DRIVEWAYS FLAT 0.12 Impervious Total 0.12 Basin Total 0.17 Element Flows To: Surface Interflow Groundwater Gravel Trench Bed C Gravel Trench Bed C Name : Gravel Trench Bed C Bottom Length: 100.00 ft. Bottom Width: 52.00 ft. Trench bottom slope 1: 0.0001 To 1 Trench Left side slope 0: 0 To 1 Trench right side slope 2: 0 To 1 Material thickness of first layer: 0.5 Pour Space of material for first layer: 0.333 Material thickness of second layer: 0 Pour Space of material for second layer: 0 Material thickness of third layer: 0 Pour Space of material for third layer: 0 Infiltration On Infiltration rate: 1.5 Infiltration safety factor: 1 Discharge Structure Riser Height: 0.5 ft. Riser Diameter: 12 in. Element Flows To: Outlet 1 Outlet 2 Gravel Trench Bed Hydraulic Table Stage(ft) Area(ac) Volume(ac-ft) Discharge(cfs) Infilt(cfs) 0.0000 0.119 0.000 0.000 0.000 0.0167 0.119 0.000 0.000 0.180 0.0333 0.119 0.001 0.000 0.180 0.0500 0.119 0.002 0.000 0.180 0.0667 0.119 0.002 0.000 0.180 0.0833 0.119 0.003 0.000 0.180 0.1000 0.119 0.004 0.000 0.180 0.1167 0.119 0.004 0.000 0.180 0.1333 0.119 0.005 0.000 0.180 0.1500 0.119 0.006 0.000 0.180 0.1667 0.119 0.006 0.000 0.180 0.1833 0.119 0.007 0.000 0.180 0.2000 0.119 0.008 0.000 0.180 0.2167 0.119 0.008 0.000 0.180 0.2333 0.119 0.009 0.000 0.180 0.2500 0.119 0.009 0.000 0.180 0.2667 0.119 0.010 0.000 0.180 0.2833 0.119 0.011 0.000 0.180 0.3000 0.119 0.011 0.000 0.180 0.3167 0.119 0.012 0.000 0.180 0.3333 0.119 0.013 0.000 0.180 0.3500 0.119 0.013 0.000 0.180 0.3667 0.119 0.014 0.000 0.180 0.3833 0.119 0.015 0.000 0.180 0.4000 0.119 0.015 0.000 0.180 0.4167 0.119 0.016 0.000 0.180 0.4333 0.119 0.017 0.000 0.180 0.4500 0.119 0.017 0.000 0.180 0.4667 0.119 0.018 0.000 0.180 0.4833 0.119 0.019 0.000 0.180 0.5000 0.119 0.019 0.000 0.180 0.5167 0.119 0.021 0.021 0.180 0.5333 0.119 0.023 0.059 0.180 0.5500 0.119 0.025 0.108 0.180 0.5667 0.119 0.027 0.167 0.180 0.5833 0.119 0.029 0.234 0.180 0.6000 0.119 0.031 0.308 0.180 0.6167 0.119 0.033 0.388 0.180 0.6333 0.119 0.035 0.474 0.180 0.6500 0.119 0.037 0.565 0.180 Page 16 0.6667 0.119 0.039 0.662 0.180 0.6833 0.119 0.041 0.764 0.180 0.7000 0.119 0.043 0.871 0.180 0.7167 0.119 0.045 0.982 0.180 0.7333 0.119 0.047 1.097 0.180 0.7500 0.119 0.049 1.217 0.180 0.7667 0.119 0.051 1.341 0.180 0.7833 0.119 0.053 1.468 0.180 0.8000 0.119 0.055 1.600 0.180 0.8167 0.119 0.057 1.735 0.180 0.8333 0.119 0.059 1.874 0.180 0.8500 0.119 0.061 2.016 0.180 0.8667 0.119 0.063 2.162 0.180 0.8833 0.119 0.065 2.311 0.180 0.9000 0.119 0.067 2.463 0.180 0.9167 0.119 0.069 2.619 0.180 0.9333 0.119 0.071 2.778 0.180 0.9500 0.119 0.073 2.939 0.180 0.9667 0.119 0.075 3.104 0.180 0.9833 0.119 0.077 3.272 0.180 1.0000 0.119 0.079 3.443 0.180 7 0.180 1.016 0.119 0.081 3.616 1.0333 0.119 0.083 3.793 0.180 1.0500 0.119 0.085 3.972 0.180 1.0667 0.119 0.087 4.154 0.180 1.0833 0.119 0.089 4.339 0.180 1.1000 0.119 0.091 4.526 0.180 1.1167 0.119 0.093 4.716 0.180 1.1333 0.119 0.095 4.908 0.180 1.1500 0.119 0.097 5.103 0.180 1.1667 0.119 0.099 5.301 0.180 1.1833 0.119 0.101 5.501 0.180 1.2000 0.119 0.103 5.703 0.180 1.2167 0.119 0.105 5.908 0.180 1.2333 0.119 0.107 6.116 0.180 1.2500 0.119 0.109 6.325 0.180 1.2667 0.119 0.111 6.537 0.180 1.2833 0.119 0.113 6.752 0.180 1.3000 0.119 0.115 6.968 0.180 1.3167 0.119 0.117 7.187 0.180 1.3333 0.119 0.119 7.408 0.180 1.3500 0.119 0.121 7.632 0.180 1.3667 0.119 0.123 7.857 0.180 1.3833 0.119 0.125 8.085 0.180 1.4000 0.119 0.127 8.315 0.180 1.4167 0.119 0.129 8.547 0.180 1.4333 0.119 0.131 8.781 0.180 1.4500 0.119 0.133 9.017 0.180 1.4667 0.119 0.135 9.256 0.180 1.4833 0.119 0.137 9.496 0.180 1.5000 0.119 0.139 9.739 0.180 ANALYSIS RESULTS Stream Protection Duration Page 17 Predeveloped Landuse Totals for POC #1 Total Pervious Area:0.38 Total Impervious Area:O Mitigated Landuse Totals for POC #1 Total Pervious Area:0.1 Total Impervious Area:0.28 Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.030048 5 year 0.049993 10 year 0.065234 25 year 0.08664 50 year 0.104071 100 year 0.122727 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0 5 year 0 10 year 0 25 year 0 50 year 0 100 year 0 Stream Protection Duration Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1956 0.026 0.000 1957 0.059 0.000 1958 0.017 0.000 1959 0.025 0.000 1960 0.042 0.000 1961 0.024 0.000 1962 0.010 0.000 1963 0.059 0.000 1964 0.033 0.000 1965 0.031 0.000 1966 0.018 0.000 1967 0.024 0.000 1968 0.019 0.000 1969 0.013 0.000 1970 0.021 0.000 1971 0.026 0.000 1972 0.060 0.000 1973 0.023 0.000 1974 0.021 0.000 1975 0.081 0.000 1976 0.049 0.000 1977 0.036 0.000 1978 0.035 0.000 1979 0.060 0.000 FkayC- 1980 0.024 0.000 1981 0.055 0.000 1982 0.025 0.000 1983 0.044 0.000 1984 0.035 0.000 1985 0.013 0.000 1986 0.042 0.000 1987 0.079 0.000 1988 0.019 0.000 1989 0.027 0.000 1990 0.072 0.000 1991 0.089 0.000 1992 0.016 0.000 1993 0.011 0.000 1994 0.010 0.000 1995 0.026 0.000 1996 0.041 0.000 1997 0.024 0.000 1998 0.038 0.000 1999 0.031 0.000 2000 0.039 0.000 2001 0.007 0.000 2002 0.032 0.000 2003 0.015 0.000 2004 0.033 0.000 2005 0.024 0.000 2006 0.030 0.000 2007 0.070 0.000 2008 0.114 0.000 Stream Protection Duration Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.1138 0.0000 2 0.0893 0.0000 3 0.0811 0.0000 4 0.0792 0.0000 5 0.0717 0.0000 6 0.0696 0.0000 7 0.0600 0.0000 8 0.0596 0.0000 9 0.0594 0.0000 10 0.0585 0.0000 11 0.0555 0.0000 12 0.0487 0.0000 13 0.0440 0.0000 14 0.0425 0.0000 15 0.0419 0.0000 16 0.0413 0.0000 17 0.0389 0.0000 18 0.0379 0.0000 19 0.0362 0.0000 20 0.0352 0.0000 21 0.0346 0.0000 22 0.0333 0.0000 23 0.0331 0.0000 24 0.0322 0.0000 25 0.0314 0.0000 26 0.0312 0.0000 27 0.0303 0.0000 28 0.0270 0.0000 29 0.0264 0.0000 30 0.0263 0.0000 31 0.0262 0.0000 32 0.0253 0.0000 33 0.0247 0.0000 34 0.0244 0.0000 35 0.0243 0.0000 36 0.0238 0.0000 37 0.0236 0.0000 38 0.0236 0.0000 39 0.0232 0.0000 40 0.0215 0.0000 41 0.0214 0.0000 42 0.0193 0.0000 43 0.0186 0.0000 44 0.0175 0.0000 45 0.0169 0.0000 46 0.0161 0.0000 47 0.0148 0.0000 48 0.0130 0.0000 49 0.0130 0.0000 50 0.0109 0.0000 51 0.0101 0.0000 52 0.0095 0.0000 53 0.0074 0.0000 Stream Protection Duration POC $1 The Facility PASSED The Facility PASSED. Flow(cfs) Predev Mit Percentage Pass/Fail 0.0150 11004 0 0 Pass 0.0159 9374 0 0 Pass 0.0168 7936 0 0 Pass 0.0177 6674 0 0 Pass 0.0186 5642 0 0 Pass 0.0195 4802 0 0 Pass 0.0204 4035 0 0 Pass 0.0213 3470 0 0 Pass 0.0222 2938 0 0 Pass 0.0231 2468 0 0 Pass 0.0240 2132 0 0 Pass 0.0249 1877 0 0 Pass 0.0258 1645 0 0 Pass 0.0267 1440 0 0 Pass 0.0276 1260 0 0 Pass 0.0285 1118 0 0 Pass 0.0294 983 0 0 Pass 0.0303 874 0 0 Pass m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m m ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro a a a a a a 01 a s 04 a 04 a a a a a, a s as a a a a a a, a s a, a a a a a a a a a a4 a a a a4 a s al a a a a4 a a a as a4 a. a . O O O O O O O O O O O O O O O o 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 O O O O O 0 0 0 O O O O O o 0 0 O O O o 0 0 0 0 0 0 0 0 0 0 0 O o 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 C. 0 0 OD m N O ri M M OO m M N Lo .-i M C LO m O m Lo C ri N O C (D r M 0 0) m r l0 LO C M N N r-1 O r 0 00 r M O C m v' m ri M LO C M M r-I r w LO C M m N N N r-I r-i ri r-I ri r-I ri ri r-1 r-I ri m m r l0 l0 LO LO 'cT C M M N ri ri ri r-I ri m 0) m m 0) 0) r 110 l0 110 l0 LO LO LO C C M N r-I O 0) OD r l0 Ln C M (N r-i O a) OD r l0 Lo C lM N .-i O Ol O r w Lo C (M N ri O Ol co r w Lo C M N ri O m 00 r l0 LO C M N r-I O m co r w ri N M M C LO l0 r OD (3) O r-I N N M C to l0 r 00 al O ri -A N M C LO W r 00 Ol O O ri N M C Lo l0 r OD 0\ M O r4 N f+') C Lo W r O OJ Ol O ri M M M M M M M M M M C C C C C C C C C C C LO LO LO LO LO LO LO LO LO LO LO l0 w w l0 110 l0 l0 l0 110 l0 110 l0 r r r r r r r r r r r OD 00 O O O O O O O O O O O O O O O O 0 0 0 0 0 0 0 0 O O 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 C. 0 0 0 0 0 . . . . C. . . . . . . C. . C. C. C. . . C. C. . . . . . C. C. . . . . . C. C. . . . C. . . . . . . . . C. . . . C. . . C. . C. C. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.0825 3 0 0 Pass 0.0834 3 0 0 Pass 0.0843 3 0 0 Pass 0.0852 3 0 0 Pass 0.0861 3 0 0 Pass 0.0870 3 0 0 Pass 0.0879 3 0 0 Pass 0.0888 3 0 0 Pass 0.0897 2 0 0 Pass 0.0906 2 0 0 Pass 0.0915 2 0 0 Pass 0.0924 2 0 0 Pass 0.0933 1 0 0 Pass 0.0942 1 0 0 Pass 0.0951 1 0 0 Pass 0.0960 1 0 0 Pass 0.0969 1 0 0 Pass 0.0978 1 0 0 Pass 0.0987 1 0 0 Pass 0.0996 1 0 0 Pass 0.1005 1 0 0 Pass 0.1014 1 0 0 Pass 0.1023 1 0 0 Pass 0.1032 1 0 0 Pass 0.1041 1 0 0 Pass Water Quality Me Flow and Volume for POC #1 On-line facility volume: 0.0321 acre-feet On-line facility target flow: 0.0171 cfs. Off-line facility target flow: 0.096 cfs. Stream Protection Duration Predeveloped Landuse Totals for POC #2 Total Pervious Area:0.16 Total Impervious Area:O Mitigated Landuse Totals for POC #2 Total Pervious Area:0.08 Total Impervious Area:0.08 Flow Frequency Return Periods for Predeveloped. POC #2 Return Period Flow(cfs) 2 year 0.012652 5 year 0.02105 10 year 0.027467 25 year 0.03648 50 year 0.043819 100 year 0.051675 Flow Frequency Return Periods for Mitigated. POC #2 Return Period Flow(cfs) 2 year 0 5 year 0 10 year 0 25 year 0 50 year 0 100 year 0 Stream Protection Duration Annual Peaks for Predeveloped and Mitigated. POC #2 Year Predeveloped Mitigated 1956 0.011 0.000 1957 0.025 0.000 1958 0.007 0.000 1959 0.011 0.000 1960 0.018 0.000 1961 0.010 0.000 1962 0.004 0.000 1963 0.025 0.000 1964 0.014 0.000 1965 0.013 0.000 1966 0.007 0.000 1967 0.010 0.000 1968 0.008 0.000 1969 0.005 0.000 1970 0.009 0.000 1971 0.011 0.000 1972 0.025 0.000 1973 0.010 0.000 1974 0.009 0.000 1975 0.034 0.000 1976 0.021 0.000 1977 0.015 0.000 1978 0.015 0.000 1979 0.025 0.000 1980 0.010 0.000 1981 0.023 0.000 1982 0.010 0.000 1983 0.019 0.000 1984 0.015 0.000 1985 0.005 0.000 1986 0.018 0.000 1987 0.033 0.000 1988 0.008 0.000 1989 0.011 0.000 1990 0.030 0.000 1991 0.038 0.000 1992 0.007 0.000 1993 0.005 0.000 1994 0.004 0.000 1995 0.011 0.000 1996 0.017 0.000 1997 0.010 0.000 1998 0.016 0.000 1999 0.013 0.000 2000 0.016 0.000 2001 0.003 0.000 2002 0.014 0.000 2003 0.006 0.000 2004 0.014 0.000 2005 0.010 0.000 2006 0.013 0.000 2007 0.029 0.000 2008 0.048 0.000 Stream Protection Duration Ranked Annual Peaks for Predeveloped and Mitigated. POC #2 Rank Predeveloped Mitigated 1 0.0479 0.0000 2 0.0376 0.0000 3 0.0342 0.0000 4 0.0334 0.0000 5 0.0302 0.0000 6 0.0293 0.0000 7 0.0253 0.0000 8 0.0251 0.0000 9 0.0250 0.0000 10 0.0246 0.0000 11 0.0234 0.0000 12 0.0205 0.0000 13 0.0185 0.0000 14 0.0179 0.0000 15 0.0177 0.0000 16 0.0174 0.0000 17 0.0164 0.0000 18 0.0160 0.0000 19 0.0152 0.0000 20 0.0148 0.0000 21 0.0146 0.0000 22 0.0140 0.0000 23 0.0139 0.0000 24 0.0135 0.0000 25 0.0132 0.0000 26 0.0132 0.0000 27 0.0128 0.0000 28 0.0114 0.0000 29 0.0111 0.0000 30 0.0111 0.0000 31 0.0110 0.0000 32 0.0107 0.0000 33 0.0104 0.0000 34 0.0103 0.0000 35 0.0102 0.0000 36 0.0100 0.0000 37 0.0100 0.0000 38 0.0099 0.0000 39 0.0098 0.0000 40 0.0090 0.0000 41 0.0090 0.0000 42 0.0081 0.0000 43 0.0078 0.0000 44 0.0074 0.0000 45 0.0071 0.0000 46 0.0068 0.0000 47 0.0062 0.0000 48 0.0055 0.0000 49 0.0055 0.0000 50 0.0046 0.0000 51 0.0042 0.0000 52 0.0040 0.0000 53 0.0031 0.0000 Stream Protection Duration POC #2 The Facility PASSED The Facility PASSED. Flow(cfs) Predev Hit Percentage Pass/Fail 0.0063 10995 0 0 Pass 0.0067 9372 0 0 Pass 0.0071 7934 0 0 Pass 0.0075 6670 0 0 Pass 0.0078 5642 0 0 Pass 0.0082 4802 0 0 Pass 0.0086 4035 0 0 Pass 0.0090 3468 0 0 Pass 0.0094 2936 0 0 Pass 0.0097 2462 0 0 Pass 0.0101 2132 0 0 Pass 0.0105 1875 0 0 Pass 0.0109 1644 0 0 Pass 0.0112 1446 0 0 Pass 0.0116 1263 0 0 Pass 0.0120 1119 0 0 Pass 0.0124 984 0 0 Pass 0.0128 874 0 0 Pass 0.0131 748 0 0 Pass 0.0135 619 0 0 Pass 0.0139 522 0 0 Pass 0.0143 401 0 0 Pass 0.0147 342 0 0 Pass 0.0150 303 0 0 Pass 0.0154 273 0 0 Pass 0.0158 238 0 0 Pass 0.0162 209 0 0 Pass 0.0166 193 0 0 Pass 0.0169 184 0 0 Pass 0.0173 175 0 0 Pass 0.0177 161 0 0 Pass 0.0181 153 0 0 Pass 0.0184 144 0 0 Pass 0.0188 135 0 0 Pass 0.0192 128 0 0 Pass 0.0196 120 0 0 Pass 0.0200 113 0 0 Pass 0.0203 105 0 0 Pass 0.0207 97 0 0 Pass 0.0211 91 0 0 Pass 0.0215 78 0 0 Pass 0.0219 67 0 0 Pass 0.0222 63 0 0 Pass 0.0226 58 0 0 Pass 0.0230 54 0 0 Pass 0.0234 49 0 0 Pass 0.0237 44 0 0 Pass 0.0241 39 0 0 Pass 0.0245 31 0 0 Pass 0.0249 23 0 0 Pass 0.0253 15 0 0 Pass 0.0256 14 0 0 Pass 0.0260 13 0 0 Pass 0.0264 13 0 0 Pass 0.0268 11 0 0 Pass 0.0272 9 0 0 Pass 0.0275 9 0 0 Pass 0.0279 9 0 0 Pass 0.0283 9 0 0 Pass 0.0287 9 0 0 Pass 0.0290 9 0 0 Pass 0.0294 7 0 0 Pass 0.0298 7 0 0 Pass 0.0302 7 0 0 Pass 0.0306 6 0 0 Pass 0.0309 6 0 0 Pass 0.0313 6 0 0 Pass 0.0317 6 0 0 Pass 0.0321 6 0 0 Pass 0.0325 5 0 0 Pass 0.0328 5 0 0 Pass 0.0332 5 0 0 Pass 0.0336 4 0 0 Pass 0.0340 4 0 0 Pass 0.0344 3 0 0 Pass 0.0347 3 0 0 Pass 0.0351 3 0 0 Pass 0.0355 3 0 0 Pass 0.0359 3 0 0 Pass 0.0362 3 0 0 Pass 0.0366 3 0 0 Pass 0.0370 3 0 0 Pass 0.0374 3 0 0 Pass 0.0378 2 0 0 Pass 0.0381 2 0 0 Pass 0.0385 2 0 0 Pass 0.0389 2 0 0 Pass 0.0393 1 0 0 Pass 0.0397 1 0 0 Pass 0.0400 1 0 0 Pass 0.0404 1 0 0 Pass 0.0408 1 0 0 Pass 0.0412 1 0 0 Pass 0.0415 1 0 0 Pass 0.0419 1 0 0 Pass 0.0423 1 0 0 Pass 0.0427 1 0 0 Pass 0.0431 1 0 0 Pass 0.0434 1 0 0 Pass 0.0438 1 0 0 Pass water Quality BHP Flow and Volume for POC #2 On-line facility volume: 0.0135 acre-feet On-line facility target flow: 0.0072 cfs. Off-line facility target flow: 0.0040 cfs. Stream Protection Duration Predeveloped Landuse Totals for POC #3 Total Pervious Area:0.17 Total Impervious Area:O Mitigated Landuse Totals for POC #3 Total Pervious Area:0.05 Total Impervious Area:0.12 Flow Frequency Return Periods for Predeveloped. POC #3 Return Period Flow(cfs) 2 year 0.013443 5 year 0.022365 10 year 0.029184 25 year 0.03876 50 year 0.046558 100 year 0.054904 Flow Frequency Return Periods for Mitigated. POC #3 Return Period Flow(cfs) 2 year 0 5 year 0 10 year 0 25 year 0 50 year 0 100 year 0 Stream Protection Duration Annual Peaks for Predeveloped and Mitigated. POC #3 Year Predeveloped Mitigated 1956 0.012 0.000 1957 0.026 0.000 1958 0.008 0.000 1959 0.011 0.000 1960 0.019 0.000 1961 0.011 0.000 1962 0.004 0.000 1963 0.027 0.000 1964 0.015 0.000 1965 0.014 0.000 1966 0.008 0.000 1967 0.011 0.000 1968 0.009 0.000 1969 0.006 0.000 1970 0.010 0.000 1971 0.012 0.000 1972 0.027 0.000 1973 0.010 0.000 1974 0.010 0.000 1975 0.036 0.000 1976 0.022 0.000 1977 0.016 0.000 1978 0.015 0.000 1979 0.027 0.000 1980 0.011 0.000 1981 0.025 0.000 1982 0.011 0.000 1983 0.020 0.000 1984 0.016 0.000 1985 0.006 0.000 1986 0.019 0.000 1987 0.035 0.000 1988 0.008 0.000 1989 0.012 0.000 1990 0.032 0.000 1991 0.040 0.000 1992 0.007 0.000 1993 0.005 0.000 1994 0.005 0.000 1995 0.012 0.000 1996 0.018 0.000 1997 0.011 0.000 1998 0.017 0.000 1999 0.014 0.000 2000 0.017 0.000 2001 0.003 0.000 2002 0.014 0.000 2003 0.007 0.000 2004 0.015 0.000 2005 0.011 0.000 2006 0.014 0.000 2007 0.031 0.000 2008 0.051 0.000 Stream Protection Duration Ranked Annual Peaks for Predeveloped and Mitigated. POC #3 Rank Predeveloped Mitigated 1 0.0509 0.0000 2 0.0400 0.0000 3 0.0363 0.0000 4 0.0354 0.0000 5 0.0321 0.0000 6 0.0311 0.0000 7 0.0269 0.0000 8 0.0267 0.0000 9 0.0266 0.0000 10 0.0262 0.0000 11 0.0248 0.0000 12 0.0218 0.0000 13 0.0197 0.0000 14 0.0190 0.0000 15 0.0188 0.0000 16 0.0185 0.0000 17 0.0174 0.0000 18 0.0170 0.0000 19 0.0162 0.0000 20 0.0158 0.0000 21 0.0155 0.0000 22 0.0149 0.0000 23 0.0148 0.0000 24 0.0144 0.0000 25 0.0141 0.0000 26 0.0140 0.0000 27 0.0136 0.0000 28 0.0121 0.0000 29 0.0118 0.0000 30 0.0117 0.0000 31 0.0117 0.0000 32 0.0113 0.0000 33 0.0111 0.0000 34 0.0109 0.0000 35 0.0109 0.0000 36 0.0107 0.0000 37 0.0106 0.0000 38 0.0106 0.0000 39 0.0104 0.0000 40 0.0096 0.0000 41 0.0096 0.0000 42 0.0086 0.0000 43 0.0083 0.0000 44 0.0078 0.0000 45 0.0076 0.0000 46 0.0072 0.0000 47 0.0066 0.0000 48 0.0058 0.0000 49 0.0058 0.0000 50 0.0049 0.0000 51 0.0045 0.0000 52 0.0043 0.0000 53 0.0033 0.0000 Stream Protection Duration POC #3 The Facility PASSED The Facility PASSED. Flow(cfs) Predev Hit Percentage Pass/Fail 0.0067 10998 0 0 Pass 0.0071 9372 0 0 Pass 0.0075 7934 0 0 Pass 0.0079 6672 0 0 Pass 0.0083 5640 0 0 Pass 0.0087 4802 0 0 Pass 0.0091 4035 0 0 Pass ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro ro aaaa, a, a. aaaaaaaaaaaaaaaaaa, aaaaaaao, aaaaaaaaaa, aaaaa. aaaaaaaa, a, a, aa 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Cl 0 0 0 0 0 0 Co 0 0 0 0 0 0 0 0 0 0 0 0 0 o O o 0 0 0 0 0 0 0 0 0 0 0 0 0 o O o 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 o O o 0 0 0 0 0 0 0 0 O k0 w N ri C' O r-I m l� M l0 M O C' V' r-i ur) V' N N CT O ri M C' CO m M In In ri m C' to O O M o C' m C' 1-1 O lfl IT N r-I 00 1` C' N N O V' O (- M O M O I` lO Ln C' M N N '-1 0 t- .--1 O0 O l•1 CO C' dl C' Ol ri M I.f) d' M M r-I M N N N r-i ri r-I r-I .--I M OD I- �,o Ln d' (Y) M N N N ri ri ri ri ri r-i r-i r-i r-i r-I r-I d\ m I- 1,o lO u) In C' aT M m N r-i r-I ri ri ri M M Ol Ol M M r- [� Ln M M I- ri l0 O d' O N l0 O C' M N l0 O d' O N �,0 O cP O N l0 O d' OD N l0 O Cr OD N l0 O '�:I' 00 N l0 O C' OD N w O Ln Ol (M 1- r-1 LO m M I- ri 0) 0) O O 1-4 1-1 N N N M M CT v' V' LO 0 lO lO l0 I- 1` O O N M M 0 0 0 r-1 ri N N (N M M C' C' C' U) LO lD lO lO (- (- M O M M M 0 0 0 r-I r-i N O O r-4 r-i .-i .l ri ri r-1 ri ri .--1 ri -1 ri ri r-I ri ri r--1 ri r-1 r-i ri r-i r-I N N N N N N N N N N N N N N N N N N N N N N N N N M M M M M iM O O O O Co O O O O O O O O O O O O 0 0 0 0 0 0 0 0 0 Cl 0 0 0 0 0 0 0 0 0 O O O O O O O O O O O O O O O O O O Cl O O . . . C. . . . . . . . . . . C. . . . . . . C. C. . . . C. . . . . . C. . . . . . . C. C. . C. . C. . C. C. C. . . . . . . . . 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.0325 6 0 0 Pass 0.0329 6 0 0 Pass 0.0333 6 0 0 Pass 0.0337 6 0 0 Pass 0.0341 6 0 0 Pass 0.0345 5 0 0 Pass 0.0349 5 0 0 Pass 0.0353 5 0 0 Pass 0.0357 4 0 0 Pass 0.0361 4 0 0 Pass 0.0365 3 0 0 Pass 0.0369 3 0 0 Pass 0.0373 3 0 0 Pass 0.0377 3 0 0 Pass 0.0381 3 0 0 Pass 0.0385 3 0 0 Pass 0.0389 3 0 0 Pass 0.0393 3 0 0 Pass 0.0397 3 0 0 Pass 0.0401 2 0 0 Pass 0.0405 2 0 0 Pass 0.0409 2 0 0 Pass 0.0413 2 0 0 Pass 0.0417 1 0 0 Pass 0.0421 1 0 0 Pass 0.0425 1 0 0 Pass 0.0429 1 0 0 Pass 0.0433 1 0 0 Pass 0.0437 1 0 0 Pass 0.0441 1 0 0 Pass 0.0445 1 0 0 Pass 0.0449 1 0 0 Pass 0.0454 1 0 0 Pass 0.0458 1 0 0 Pass 0.0462 1 0 0 Pass 0.0466 1 0 0 Pass Water Quality BW Flow and Volume for POC #3 On-line facility volume: 0.0143 acre-feet On-line facility target flow: 0.0076 cfe. Off-line facility target flow: 0.0043 cfe. 10. EROSION AND SEDIMENT CONTROL Erosion and sediment control work is a continuous and ongoing element of the construction phase of the project. Erosion and sediment control work is the first aspect of project construction and will continue beyond the active construction phase of the project. The Temporary Erosion and Sediment Control Plan include the standard notes for the Best Management Practice along for measures directed specifically for this site. The erosion control measures used for this site include a construction entrance and silt fence at the south end of the swale and fill sections. Page 31 APPENDIX A Wnek Engineering Infiltration Report WNEK ENGINEERING Consulting Civil Engineer 3388 NW Byron St., Suite 200, Silverdale, WA 98383 360-692-3802 (fax)-692-1051 Infiltration Report Taco Bell SR 3 & NE Old Clifton Rd located in: BELFAIR, WA prepared for: Pat McCullough 210 Cherokee Beach Rd. NE Belfair, WA 98528 date: May 19, 2014 Contents: SUMMARY.................................Pg 1 APPENDIX A..............................Pg 3 SITE PLAN & PIT LOCATIONS......Pg 4 TEST PIT DATA..........................Pg 5 USDA SOIL CLASSIFICATION......Pg 10 CEC TESTING............................Pg 12 MFW Project Number: 624 By the seal and signature here affixed, I certify that the enclosed report was accomplished by myself, and that I am currently a registered engineer of good standing in the State of Washington. i Taco Bell — Belfair WNEK ENGINEERING Infiltration Testing Report May 19, 2014 SUMMARY In accordance with our proposal, Wnek Engineering performed infiltration tests at five locations on the referenced site on April 30, 2014. The percolation tests were performed using the Falling Head Percolation Test Procedure. Percolation tests were performed on all five test pits. Soil samples for Cation Exchange Capacity(CEC)and USDA sieve analysis were also collected from locations TP #1, TP#4 and TP#5. The remainder of the test pits were logged. At the time of the site visit the area of the parcel was a vacant lot with a gravelly driving surface to the southeast along S.R. 3,and pasture to the northwest. Test pits TP #1 through TP #5 were located throughout the porous pavement area. Test pits were excavated by a hand using a pickaxe and shovel. Test pit logs are attached to this letter. The test pits were excavated to depths ranging from 1.5 to 2.5 feet in depth. Groundwater seepage was not encountered in any test pits. Soil samples were collected from the bottom of test pit TP #1, TP #4 and TP #5. Soil samples were submitted to Phoenix Soil Research for USDA Sieve Analysis and also were submitted to Twiss Analytical Laboratories for Cation Exchange Capacity (CEC) analysis. Laboratory test results are attached to this letter. Each test pit was a 14 to 30-inch deep hole approximately 6 inches in diameter at the anticipated elevation of the bottom of the porous pavement subgrade. Each test hole was presoaked with water prior to the infiltration test. Test holes were filled with 10-12 inches of water which was allowed to drain while measurements were taken at 5 minute intervals for each test. Water was placed in each test hole and measured from a fixed reference point. The tests were performed until a steady state was reached in percolation measurements. Each percolation rate is then modified according to Washington DOE standard for the design rate, calculations are attached in Appendix A. The percolation rates based on the test results are as follows: Test Pit#1 — 1.20 inches per hour;0.39 inches per hour design rate. Test Pit#2—6.96 inches per hour; 2.26 inches per hour design rate. Test Pit#3— 10.68 inches per hour; 3.46 inches per hour design rate. Test Pit#4—3.00 inches per hour; 1.03 inches per hour design rate. Test Pit#5—0.48 inches per hour; 0.16 inches per hour design rate. Page-1 Taco Bell - Belfair WNEK ENGINEERING Infiltration Testing Report May 19, 2014 USDA sieve results from the collected soil samples classified the soils in test pits (TP#4 and TP #5) as loamy sand, and pit TP#1 as sand. Sieve analysis results are attached to this letter. Cation exchange capacity (CEC) tests utilizing EPA Method 9081 was performed on the soil samples from the same test pits by Twiss Analytical to estimate the ability of in-place soils to provide storm treatment. The results of the tests are attached to this report. The test pit sample results were 15.0 milliequivalents/100grams for test pit TP#1, 9.52 meq/100g for test pit TP#4, 9.54 meq/100g for test pit TP #5. Current guidelines require a CEC equal to or greater than 5 for storm treatment facilities using infiltration. We have prepared this letter based on standard practices, currently used in this area at the time of preparation. The conclusions are based on the observations made during the site visit. The information presented in this letter was collected and interpreted in a manner consistent with the level of care and skill ordinarily exercised by members of the profession currently practicing under similar conditions. No other warranty, expressed or implied, including (but not limited to) any warranty of merchantability or fitness for a particular use has been made. Should you have any questions or concerns, which have not been addressed,or if we may be of additional assistance,please call our office at(360)692-3802. Page-2 Taco Bell— Belfair WNEK ENGINEERING Infiltration Testing Report May 19, 2014 APPENDIX A The Dept. of Ecology guidelines for correction factors are used to reduce the initial measurements to a design infiltration rate for hydrology modeling. The total correction factor is the product of three factors: Site Variability, CFv =0.90 The site was tested in multiple locations to determine any variability and account for that in the design of the porous pavement. Test Method,CFt 0.40 Infiltration test pits used a falling head method of measuring infiltration rates. Each pit was pre-soaked to give infiltration rates in saturated soil conditions. These methods are less time and cost intensive than larger scale testing methods,but can give an accurate description of infiltration rates when used in multiple locations on a project site. Influent Control, CFm =0.9 Soil infiltration rates will decline as stormwater passes through the soil profile. Typical maintenance calls for sediment removal when the facility is infiltrating at 90%of design capacity,therefore a correction factor of 0.9 is applied. CFT=CFv*CFt*CF.=0.90 * 0.40 * 0.90= 0.342 total correction factor. The testing method used was a falling head test. The testing method is as follows: 1. Each infiltration test pit was excavated to the approximate depth of the porous pavement subgrade. 2. Each pit was filled to a specified mark to pre-soak the soils in order to create a saturated condition and provide infiltration rates found during large storm events. Each pit was maintained in this condition for thirty minutes. 3. After pre-soaking the soils,the pit was allowed to drain,with depth measurements taken every five minutes for thirty minutes to indicate the infiltration rate. Each test pit was averaged across the measurements taken for each five minute interval to give an initial hourly infiltration rate. The initial rates are then reduced based on the correction factors provided by the Dept. of Ecology. Page-3 Taco Bell - Belfair WNEK ENGINEERING Infiltration Pit Locations May 1, 2014 NORTH SITE PLAN & PIT LOCATIONS NOT TO SCALE 8 ° ® Z 57.50 88............ ---, .50 TEST PIT' I 3 0 � Q �G -A TEST PIT #4 n TEST PIT #2 Z $ rp :•+ 1 YI jv N 4 R 'ry`i• TEST PIT #5 UTILITY 1 4 �� BOXES TEST PIT 1 c BPS Page 4 WNEK ENGINEERING Consulting Civil Engineer 3388 NW Byron St., Suite 200, Silverdale, WA 98383 360-692-3802 (fax}692-1051 SOIL INFILTRATION TEST Date: April 30, 2014 Project: Taco Bell - Belfair Method: Hand Tools, Pre-soak, 30 minute infiltration test, repeat until constant Number: Test Pit - 2 Location: West side of property, center of drive lane Pit Total Depth: 30 (inches) Pit Water Level: 0.77 (feet) Pit setup: Dig pit to expected depth of infiltration facility: —101, Time (min) Depth (ft) Depth(T-5)-Depth(T) Infiltration rate (in/hr) 0 0.77 0 0 5 0.63 0.14 10.08 10 0.52 0.11 7.92 15 0.44 0.08 5.76 20 0.34 0.10 7.20 25 0.29 0.05 3.60 30 0.19 0.10 7.20 Average Infiltration Rate: 6.96 inches/hour Page 6 WNEK ENGINEERING Consulting Civil Engineer 3388 NW Byron St., Suite 200, Silverdale, WA 98383 360-692-3802 (fax}692-1051 SOIL INFILTRATION TEST Date: April 30, 2014 Project: Taco Bell - Belfair Method: Hand Tools, Pre-soak, 30 minute infiltration test, repeat until constant Number: Test Pit - 3 Location: Northern part of property, center of main parking area. Pit Total Depth: 14 (inches) Pit Water Level: 10 (inches) Pit setup: Dig pit to expected depth of infiltration facility: -r101, Time (min) Depth (ft) Depth(T-5)-Depth(T) Infiltration rate (in/hr) 0 0.59 0 0 5 0.41 0.18 12.96 10 0.24 0.17 12.24 15 (filled to 0.50)* 0.10 0.14 10.08 20 0.31 0.19 13.68 25 0.21 0.10 7.20 30 0.10 1 0.11 7.92 Average Infiltration Rate: 10.68 inches/hour Page 7 WNEK ENGINEERING Consulting Civil Engineer 3388 NW Byron St., Suite 200, Silverdale, WA 98383 360-692-3802 (fax}692-1051 SOIL INFILTRATION TEST Date: April 30, 2014 Project: Taco Bell - Belfair Method: Hand Tools, Pre-soak, 30 minute infiltration test, repeat until constant Number: Test Pit -4 Location: East property line, center of lot. Pit Total Depth: 14 (inches) Pit Water Level: 10 (inches) Pit setup: Dig pit to expected depth of infiltration facility: —101, Time (min) Depth (ft) Depth(T-5)-Depth(T) Infiltration rate (in/hr) 0 0.77 0 0 5 0.71 0.06 4.32 10 0.67 0.04 2.88 15 0.62 0.05 3.60 20 0.59 0.03 2.16 25 0.57 0.02 1.44 30 0.52 0.05 3.60 Average Infiltration Rate: 3.0 inches/hour Sample taken @ 14" depth Page 8 WNEK ENGINEERING Consulting Civil Engineer 3388 NW Byron St., Suite 200, Silverdale, WA 98383 360-692-3802 (fmx 692-1051 SOIL INFILTRATION TEST Date: April 30, 2014 Project: Taco Bell - Belfair Method: Hand Tools, Pre-soak, 30 minute infiltration test, repeat until constant Number: Test Pit - 5 Location: South property line, center of lot, drive through lane. Pit Total Depth: 14 (inches) Pit Water Level: 10 (inches) Pit setup: Dig pit to expected depth of infiltration facility: —101, Time (min) Depth (ft) Depth(T-5)-Depth(T) Infiltration rate (in/hr) 0 0.67 0 0 5 0.66 0.01 0.72 10 0.65 0.01 0.72 15 0.63 0.02 1.44 20 0.63 0.00 0 25 0.63 0.00 0 30 0.63 0.00 0 Average Infiltration Rate: 0.48 inches/hour Sample taken @ 14"depth Page 9 F _ USDA Soil Classification KO 80 ry 70 IV / \ L \ �C silty �. tay s ndy lay siltyy � lay Loam clay to m o sandy la loam 8 silty. / loam , — and loam loamy / s nd\ san\ silt 8 0 $ 1b Z 5 115 1b 115 16o PlIIID111flt Sand SOIL DATA Source Sample Depth Percentages From Material Passing a#10 Sieve Classification No. Sand Silt Clay TP1 87.6 11.2 1.2 Sand ■ TP4 76.3 21.3 2.4 Loamy sand • TP5 75.8 21.8 2.4 Loamy sand Phoenix Soil Research Client: Wnek Engineering Project: Taco Bell Belfair 624 Kingston, WA Project No.: PSR14-23-0503 Figure 2 Page 10 Particle Size Distribution Report < _ C C C � C C tt►► G NC G a C �0 C V (Gy 100 I I I I I I I I I I I I I 90 - I I I I I I I I I I I I I I I I I I I I I I I I 80 I I I I I I I I I I I I I I 70 I I I I I I I I I I I I I Z 60 I I I I I I I I I I Z 50 I I I I I I I I w I I I I I I I I I I I w 40 - a30 I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I 20 I I I I I I I I I I I I I I I I I I I I I I I I I 10 I I I I I I I I I I I I I Ml_ 0 100 10 1 0.1 0.01 0.001 0.0001 GRAIN SIZE-mm. +3" %GRAVEL %SAND %SILT %CLAY USCS AASHTO PL LL 0 0.0 42.0 50.8 7.2 ❑ 43.9 13.6 0.0 42.2 43.8 14.0 SIEVE PERCENT FINER SIEVE PERCENT FINER Material Descri to ion inches 0 El ° number O ❑ ° 0 size size 1 100.0 #4 69.8 68.1 69.2 .75 100.0 91.8 100.0 #10 58.0 57.5 57.8 ❑ .5 96.5 86.4 82.1 #18 50.8 51.5 52.7 .375 84.0 82.1 80.1 #35 42.4 45.0 45.9 #60 25.6 32.3 32.8 ° #140 12.2 20.0 20.4 #200 9.3 16.5 16.9 GRAIN SIZE #270 7.2 13.6 14.0 REMARKS: D60 2.3293 2.6010 2.5085 0 D30 0.2993 0.21% 0.2140 D10 0.0825 ❑ COEFFICIENTS Cc 0.47 ° Cu 28.24 If 0 Sample Number:TPI Sample Number:TP4 Sample Number:TP5 Phoenix Soil Research Client: Wnek Engineering Project: Taco Bell Belfair 624 Kingston, WA Project No.: PSR14-23-0503 Fg ure 1 Page 11 4 • LABORATORIES ENVIROSTARS it a SPECTRA Laboratories company May 14, 2014 Michael Wnek Wnek Engineering 3388 Byron St Ste 200 Silverdale,WA 98383 Project: Taco Bell Belfair Lab Work Order#: 140419 Sample Date: 4/30/14 Date Received: 5/2/14 Sample ID: TP#1 Lab No: 140419-01 Parameter Method Result Units Date Analyzed CEC EPA 9081 Mod 15.0 meq/100g 5/13/14 Sample ID: TP#4 Lab No: 140419-02 Parameter Method Result Units Date Analyzed CEC EPA 9081 Mod 9.52 meq/100g 5/13/14 Sample ID: TP#5 Lab No: 140419-03 Parameter Method Result Units Date Analyzed CEC EPA 9081 Mod 9.54 meq/100g 5/13/14 Approved for Release, Steven G. ffibbs Laboratory Manager WDOE Accreditation#C594 This report is issued solely for the person or company to whom it is addressed. This laboratory accepts responsibility only for the due performance of analysis according to industry accepted practice. Twiss Laboratories,Inc.or its employees are not responsible for consequential damages in any kind or in any amount. 26276 Twelve Trees Lane,Suite C A Poulsbo,WA 98370 A (360) 779-5141 A Fax: (360)779-5150 www.twisslabs.com Page 12 f Twiss Laboratories Quality Control Report Project: Taco Bell Belfair Lab Work Order#: 140419 Sample Date: 4/30/14 Date Received: 5/2/14 Method EPA 9081 Mod Blank Parameter Result Date CEC <1 meq/4-00g 5/13/14 Laboratory Check Standard Parameter QC Sample ID True Value Result % Recovery Date CEC 2013-119 9.70 meq/100g 7.37 meq/IOOg 76.0 5/13/14 Sample Duplicate Parameter QC Sample ID Sample Result Duplicate Result %RPD Date CEC 140419-03 dup 9.54 meq/100g 10.0 meq/100g 4.7 5/13/14 Approved for Release, *6�/1q. / 6 A� Steven G.Hibbs Laboratory Manager WDOE Accreditation#C594 This report is issued solely for the person or company to whom it is addressed. This laboratory accepts responsibility only for the due performance of analysis according to industry accepted practice. Twiss Laboratories,Inc.or its employees are not responsible for consequential damages in any kind or in any amount. 2 Page 13 Twiss Analyticpl Laboratories, Inc. 26276 Twelve Trees Lane, Suite C Poulsbo,WA 98370 (360)779-51411 FAX(360)779-5150 Date: Environmental Company: W r,e- km"►����� a a Address:_3388 Byron Street Ste 200 City:_Silverdale State: WA Zip:_98383 w z f F a W �,I� z 6 x a► LL Project Manager/Report To: [Y`t� W�e v a d 0 V G N Project Name: - � � 's 9 m 0 V 0 V W Phone/Fax No.: 36o 0 2- SID Z °D E M W o U 0 O z J x ri O Sample ID Date Time Matrix Lab ID 12:oo Sa\ -U 30 VW 50 14— H ILE - -O I Ifi I i Sample Receipt Standard TAT II� SIGNATURES(Name,Co pany,Date, e . Total#of Containers 10 working days orlless (� 1. Relinquished By: COC Seals Present? TAT: RUSH COC Seals Intact? 5 working days or less: (specify) OAM C 5 A�Y' S — (Printed Name,C pany bate and Time) Temp at Receipt Non-Standard TAT 3- 7 T t Received Intact? (Specify) Received By: i 7 1 L- Received Via: Return Sample to Client 2. Relinquished By: Spec4l Instructions: v , I (Printed Name,Company,Date and Time) A ? Received By: i I