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HomeMy WebLinkAboutDrainage Analysis - PLN General - 5/9/2012i WNEK ENGINEERING Consulting Civil Engineer 3388 NW Byron St., Suite 200 Silverdale, WA 98383 360-692-3802 Drainage Analysis Belfair Log Plaza (2012 Redevelopment Project) #23730 NE Highway 3, Belfair WA 12329-44-00010 located in: MASON COUNTY prepared for: Belfair Log Plaza LLC 7728 NE North St. Bainbridge Island, WA 98110 date: May 09, 2012 L F 05-09-12 o023 60 ' rs ° ti NAL NOTE: THIS DOCUMENT IS INSCRIBED WITH A DIGITIZED SIGNATURE dt DATE. THE ORIGINAL SIGNATURE DOCUMENT IS ARCHIVED IN THE ENGINEER'S OFFICE. Contents: MFW Project Number: 553 A. PARCEL DOCUMENTATION B. PROJECT DESCRIPTION By the seal and signature here affixed, C. EXISTING CONDITIONS I certify that the enclosed report was D. DRAINAGE ANALYSIS accomplished by myself, and that I am E. EXHIBITS & CALCULATIONS currently a registered engineer of good standing in the State of Washington. 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DISCLAIMER AND LIMI1AI70N OF LIABILITY: The data used to make this map have been tested for accuracy,and every effort has been made to ensure that these data are timely,accurate and reliable.However,Mason County LEGEND makes no guarantee or warranty to its accuracy as to labeling,dimensions,or placement or location of any map features contained herein.The boundaries depicted by these data are Roads LJ Fedrat Land$ approximate,and are not necessarily accurate to surveying or engineering standards,and arc intended for informational purposes only.Mason County does not assume any legal liability H19riway5 City of Shelton or responsibility arising from the use of this map in a manner not intended by Mason County. In no event shall Mason County be liable for direct,indirect,incidental,consequential, RjYws 9 Streams Cowdy Boundary IDNR) special,or tort damages of any kind,including,but not limited to,loss of anticipated profits parcels COmrrlisstOr+ar Districts or benefits arising from use of or reliance on the information contained herein Sections S Lakes GO0 2009-Mason County GIS I 100 W.Public Works Dr Townships f Puget Bound R MavY lakes Shelton,WA 98584 A-1 MASON COUNTY �f WASHINGTON TAXSIFTER SIMPLE SEARCH SALES SEARCH REETSIFTER COUNTY HOME PAGE CONTACT DISCLAIMER Melody Peterson Mason County Assessor 411 N STH ST Shelton,WA 98584 Parcel Parcel#: 12329-44-00010 Owner Name: BELFAIR LOG PLAZA LLC Land Use Code: 53 -Trade-General Merchandise Addressl: 7728 NE NORTH ST Situs: 23730 NE HIGHWAY 3 BELFAIR Address2: Map Number: City,State: BAINBRIDGE ISLANDWA Status: Zip: 98110 Description: TR 1 OF SE SE S 1/124 Comment: 2012 Market Value 2012 Taxable Value 2012 Assessment Data Land: $392,040 Land: { $392,040,lOieAd: _ . .__...__,...._ 0_2 7_6—.-.-_..T_a_x.-D.—i..s.tic._.�0-2—N7�-6oaI' Improvements: $433,000 Imp rovements: $433,000, CWre Ue/DPI. Permanent Crop: $0 jTotai $825,040, Total $825,040 Total Acres Ownership Owner's Name all N sldp 1r EELFAIR LOG PLAZA LLC l00 M Sale: History Sale Sales # Excise• Grantor Granbee Price Date Document Parcels 1 01/25/12 1984398 1 j 12-12953 XITSAP CREDIT UNION BELFAIR LOG PLAZA LLC 1$497 500 ._.._ _._.._ . 01/05/11 11968295 1 111-10085 THREE POINT PROPERTIES KITSAP CREDIT UNION 0 08/21/03 1790306 1 i200368134 KENNETH&MICHELE THREE POINT PROPERTIES LLC $340000I BLAKE 08/21/03 1790305 1 1200368133 MICHAEL L DICK,TRUSTEE THREE POINT PROPERTIES LLC $340,000 03/10/94 583778 1 199426678 MICHAEL L DICK MICKAEL L DICK TRSTEE DICK LIVING $0 TRUST OW14/93 564834 1 199322378 MILLY J DICK MICHAEL L DICK $0 11/15/09 501381 1 198904045 LOUIS V DOMINGUEZ ETLIX KENNETH A BLAKE ET UX(MICHELE T) f350,0001 11/15/09 501362 1 198904046,KENNETH A BLAKE ET UX KENNETH BLAKE ETUX A MICHAEL DICKETUX =125,0001 Historical Valuation Info Year Billed Owner 1 Land Impr. PermCrop Value Total Exempt Taxable 2012 MPAIR LOG PLAZA LLC $392,040 $433,0001: ;Q $825,040 $0 $825,040 2010 THREE POINT PROPERTIES ~� $392,040' 356,000 —� �^ 7 8 40 0 8 I 2011 KITSA►CREDIT UNION I $392,040 $433,000 $0 $825,040 $0 $825,040 2009 THREE POINT PROPERTIES �- - { $392,040, -$356,0006 - -OI $748,040 $01 $748,0401 2008 THREE POINT PROPERTIES $392,040; $356,000 0' $748,040 $0 $740,0401 A-2 BELFAIR LOG PLAZA WNEK ENGINEERING Project Documentation May 09, 2012 1. PROJECT DESCRIPTION a. Type of Permits Building Permit Mason County Land Modification Permit Mason County b. Land Use Data Zoning: Mixed Use Urban Growth Area: Belfair c. Proposed Site Improvements - Existing building remodel - Provide 11 new parking spaces - Landscaping d. Total Parcel Area = 1.00 acres e. Impervious Surfaces Proposed: Porous pavement: 7,200 sf = 0.175 acre f. Pervious Surfaces Landscape buffer: 0.043 acre g. Relevant Reports Soils: None required Geotechnical: None required Wetland / Stream: None required Other: None required B-1 BELFAIR LOG PLAZA WNEK ENGINEERING Existing Conditions May 09, 2012 2. EXISTING CONDITIONS a. Topography Average Slope: < 5% Maximum Slope: Approximately 2:1 (landscape buffer) Declivity: Westerly b. Land Cover Existing development, building & parking. c. Land Use Commercial d. Abutting Property Land Cover & Use Along highway = commercial West = vacant residential e. Offsite Drainage Onto Property None, upstream flows are deflected to south f. Environmentally Sensitive Areas Creeks, Lakes, Ponds, Wetlands - None Ravines, Gulleys, Steep Slopes - None Springs, Env. Sensitive Areas - None g. Fuel Tanks, Wells, & Septic Systems Fuel Tanks: None known Wells: The area is served by public water. Septic Systems: Belfair has recently installed public sewers. h. Soils (USDA) The USDA mapping is Eh, Everett gravelly sandy loam. Locally the native soils contain high organic content due to seepages i. Groundwater Exposed soil behind the building show seepage within 3-ft of the surface. j. Adjacent Drainage Facilities Storm Sewers: SR-3 Roadside Ditch & Culverts: SR-3 Upstream Detention: None known Downstream Detention Systems: None known k. Drainage Discharge Points Northwest corner of site, to SR-3 roadside ditch. C-1 i BELFAIR LOG PLAZA WNEK ENGINEERING Drainage Analysis May 09, 2012 3. OVERVIEW The project is a redevelopment. The flow chart for storm mitigation follows at the end of this Section. The availability of public sewer has allowed the demolition of the septic drainfield, and construction of additional parking of approximately 7,200 square feet. Technical References: - Stormwater Management Manual for Western Washington, WSDOE, February 2005 - Low Impact Development, Puget Sound Action Team, January 2005 4. MINIMUM TECHNICAL REQUIREMENTS (MR) REVIEW a. MR#1, Preparation of Stormwater Site Plans A stormwater site plan has been provided for the project. b. MR#2, Construction Stromwater Pollution Prevention (SWPP) The SWPP controls are incorporated into the grading and erosion control plan. The site will disturb less than 1 acre, therefore an NPDES construction permit is not required. c. MR#3, Source Control of Pollution There is no proposed exterior storage areas proposed. There will be no heavy equipment storage, or significant truck usage. There will be no re-fueling area. There are no source controls warranted. d. MR#4, Preservation of Natural Drainage Systems and Outfalls The proposed condition will discharge to the same location as the existing condition: roadside ditch & storm sewer of SR-3. e. MR#5, On-Site Stormwater Management Stormwater management techniques are required, the following are proposed: Porous Pavement f. MR#6, Runoff Treatment For this project, the pollution-generating impervious surfaces (PGIS) will be comprised of vehicle parking areas. The project meets the minimum threshold for requiring runoff treatment. The native soils have a 'cation exchange capacity' (CEC) value greater than '5' and are therefore adequate to provide treatment beneath the pervious pavement. Table 4.1 Treatment Requirements by Threshold Dischar a Area <%acres of >%acres <5,000 sf >51000 sf PGPS PEPS PGIS PGIS Treatment Facilities Onsitc Stormwater 13MPs POPS=pollution-generating pervious surfaces PGIS—pollution-generating impervious surfaces sf=square feet D-1 BELFAIR LOG PLAZA WNEK ENGINEERING Drainage Analysis May 09, 2012 g. MR#7, Flow Control The project does not meet the minimum threshold for flow control requirements. However, placing an underdrain beneath the porous pavement allowed the storage rock depth to be economized. The outlet of the underdrain is equipped with an orifice control so that the base infiltration flow rate can be balanced with the required Water Quality flow rate. Table 4.2 Flow Control Requirements by Threshold Discharge Area Flo" Control On-site stormntiater Facilities Management BVPs <3/,acres conversion to lair idandscape, or<2.5 acres to pasture >_'/,acres com ersion to hnnrllandscape, v _ or>2.5 acres to pasture <10,000 square feet of effective impervious area >10,000 square feet of effective impervious area >0.1 cubic feet per second increase in the 100-year flood fre uency h. MR#8, Wetlands Protection Not applicable. i. MR#9, Basin/Watershed Planning Not applicable. j. MR#10, Operations and Maintenance A Stormwater O&M Manual for the project will be provided after completion of construction. 5. WATERSHED DESCRIPTION a. Contributing Basin The project basin contributes to an urban watershed that eventually flows to Hood Canal. b. Receiving Waters Adequate Receiving Body No Downstream Enclosed Sewer or Manmade Channel Yes Stream or Wetland No c. Watershed Description A mixture of commercial properties along the SR-3 frontage, with various vacant or residential properties away from the highway. D-2 BELFAIR LOG PLAZA WNEK ENGINEERING Drainage Analysis May 09, 2012 6. DESCRIPTION OF UPSTREAM BASINS a. Sources of Runoff Onto Project Site Minimal. See Section 2.e. 'Existing Conditions, Offsite Drainage Onto Property' b. Existing Drainage & Erosion Problems No obvious drainage/erosion problems within the upstream basin. 7. DOWNSTREAM ANALYSIS (Level 1) a. Field Inspection A general field inspection & inventory of the downstream route was performed on April 26, 2012. The project areas discharges to the east roadside ditch of SR-3, then flow south under driveway approaches where it enters the storm sewer system of SR-3. It was not practical to follow the storm sewer route to its outlet point. b. Structures & Channel Driveway approach culverts & open ditches, discharging to storm sewer along SR-3. c. Problem Areas Storm drainage has historically been an problem along SR-3. The storm system components are to be reconstructed in future construction projects for the highway. d. Summary With the flow control provisions added to the porous pavement system, the project wi'I create no increase in runoff to the downstream basin, from the existing condition. 8. SOILS REPORT None warranted. Natives soils are exposed and readily identifiable. See section 11.c. 9. GEOTECHNICAL REPORT None required. 10. BASIN MAPS PROPOSED BASIN PLAN - Shows the proposed redevelopment areas. 11. ANALYSIS & CALCULATIONS a. Methodology The "Western Washington Hydrology Model" (Continuous Simulation) is used for analysis of the pervious (porous) pavement using WWHM4 software. D-3 BELFAIR LOG PLAZA WNEK ENGINEERING Drainage Analysis May 09, 2012 b. References See Section 3, "Overview" c. Soils Native soils were inspected from existing cut banks and trenching east of the existing building. The soils are categorized as loam and have adequate nutrient levels to provide water quality treatment (cation exchange capacity > 5). The native soils have adequate depth to meet infiltration criteria. d. Hydrology Porous Pavement - WWHM4 continuous simulation modeling for infiltration & orifice controls are attached. e. Hydraulic Only the roof area will be transported by underground piping, en-route to the dispersion trenches. f. Flow Control Although flow control criteria is not technically required it is employed to reduce the required depth of storage rock beneath the porous pavement. The control orifice riser is designed to meet the existing condition (forested) runoff rates. g. Treatment Treatment requirements for the PGIS is provided by the native soils having a sufficient CEC factor. 12. EROSION CONTROL There will be minimal disturbed area for this project. Grades within the work area are very flat. The potential for off-site sediment transport is minimal. All the runoff from the construction area must pass through the under-drain, which will provide a filtering mechanism. The native soil classification (Everett) is generally coarse textured, and not easily transported by non-concentrated runoff. In the project area, the soils contain significant organic material, which will be more difficult to settle-out if allowed to become mixed into the storm runoff. The construction of the porous pavement, requiring a bed of drain rock for storage, will provide additional protection to the native soils. 13. OPERATIONS & MAINTENANCE An operations & maintenance covenant for stormwater will need to be recorded with Mason County prior to final acceptance of the completed work. D-4 BELFAIR LOG PLAZA Do the new,replaced,or new plus replaced impervious surfaces total 2,000 square feet or more? 77.200 sf OR Does the land disturbing activity total 7,000 square feet or more? Yes No Minimum Requirements#1 through#5 Apply Minimum Requirement#2, apply to the new and replaced impervious Construction Stormwater Pollution surfaces and the land disturbed. Prevention Next Question Does the project add 5,000 square feet or more of new impervious surfaces? 7 00 sf OR Convert 3/e acres or more of native vegetation to lawn or landscaped areas? OR Convert 2.5 acres or more of native vegetation to pasture? Yes Next No Minimum Requirements#1 through#10 Question 10, Is this a road- apply to the new impervious surfaces and related project? the converted pervious surfaces. Yes No Does the project add 5,000 square feet or more of new impervious surfaces? Yes No Do new impervious surfaces add 50%or Is the total of the new plus replaced more to the existing impervious surfaces impervious surfaces 5,000 square feet or within the project limits? more,AND does the value of the proposed improvements—including No Yes interior improvements—exceed 50%of the assessed value(or replacement value) No additional of the existing site improvements? requirements Yes No No additional Minimum Requirements#1 through#10 requirements apply to the new and replaced impervious surfaces. Figure 2.3— Flow Chart for Determining Requirements for Redevelopment 2-10 Volume I—Minimum Technical Requirements February 2005 D-5 BELFAIR LOG PLAZA WNEK ENGINEERING Drainage Analysis May 09, 2012 PROPOSED BASIN PLAN / Dom Bled \ SCALE. ` \ t, Tole maker P.O.Pa4r4 %l-'8 Pic P�4�--��,•p"c `— / Utacr 6'wooe trace L S89'0po8'02'E 166.04' P \ p M \4 utility 0 Bend Mark p ` Top /MAG Noil \ (� r E1=51.61'NAVD88 ) Q Cont.Pod^• f Propane \. 6 Power Took Filling 1 Station •6•�Lonc<ete. \\ ��0 : •.�..efeiting wal \ y 58 c/o `o .......•••••••. c . / Spor-�= •••••••••• ••• Cigh rs G J / t Sign —7 L.B. Post . rC "�:: h Top-48.66' •pq I o �Q \ O CL 1E-47.46'6"West CC Gj /4� If to East Un nown pales 4 .N E y�t4ity .. .... . Meters ^',..... . N Si A e a •S 3 A h 6•Con Sub—Basin #2 retain' roN Power 4 a n \ _ Vault ••~5•• •ti o / l W >1: o Buffet Acres L—P I :.:......� 1`B57 SF \ 2 a4r .......... \ •�•Gay>ie.. L` ref'o:h:n9' o�T A Bench Mork Top of MAC Noil {j E1-49.47'NAV088 I • • • •• •• • rq�RsyFo J N �' 6'Concrete N89'08'07'w 209,02'_ / retaining wall I ' C Found I"Iron Pipe 'v 08'West of cam r. I \ E-1 WWHM4 PROJECT REPORT Project Name: Porous Concrete 2 Site Name Belfair Log Plaza Site Address: #23730 NE SR-3 City Mason Co. Report Date : 5/9/2012 Gage Quilcene Data Start 1955/10/01 Data End 1999/09/30 Precip Scale: 1.22 Version 2011/12/23 PREDEVELOPED LAND USE Name Basin 1 Bypass: No Groundwater: No Pervious Land Use Acres C, Forest, Steep .208 Impervious Land Use Acres Element Flows To: Surface Interflow Groundwater MITIGATED LAND USE Name Basin 1 Bypass: No Groundwater: No Pervious Land Use Acres C, Lawn, Flat .043 Impervious Land Use Acres SIDEWALKS FLAT 0.061 (standard concrete) Porous Pavement 0.104 (porous concrete) Element Flows To: Surface Interflow Groundwater Gravel Trench Bed 1 Gravel Trench Bed 1 E-2 Name Gravel Trench Bed 1 Bottom Length: 185.00 ft. (Bed area includes area under sidewalk) Bottom Width : 38 . 90 ft. Trench bottom slope 1: 0.001 To 1 Trench Left side slope 0: 0 To 1 Trench right side slope 2: 0 To 1 Material thickness of first layer : 0.583 Pour Space of material for first layer : 0.2 Material thickness of second layer : 0.417 Pour Space of material for second layer 0.33 Material thickness of third layer : 0 Pour Space of material for third layer 0 Infiltration On Infiltration rate 0.5 (USDA chart value = loam) Infiltration saftey factor 0.75 Discharge Structure Riser Height: 1 ft. Riser Diameter: 6 in. Orifice 1 Diameter: 0.75 in. Elevation: -1 ft. 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 0.165 0.000 0. 014 0.000 0.0222 0. 165 0.000 0. 014 0.062 0.0444 0.165 0.001 0.015 0.062 0.0667 0.165 0.002 0.015 0. 062 0. 0889 0.165 0.002 0.015 0.062 0. 1111 0.165 0.003 0.015 0.062 0.1333 0.165 0.004 0.015 0.062 0.1556 0.165 0.005 0.015 0.062 0.1778 0.165 0.005 0.016 0.062 0.2000 0.165 0.006 0.016 0.062 0.2222 0.165 0.007 0.016 0.062 0.2444 0.165 0.008 0.016 0.062 0.2667 0.165 0.008 0. 016 0.062 0.2889 0.165 0.009 0.016 0.062 0.3111 0.165 0.010 0.016 0.062 0.3333 0.165 0.011 0.017 0.062 0.3556 0.165 0.011 0.017 0.062 0.3778 0.165 0.012 0.017 0.062 0.4000 0.165 0.013 0. 017 0.062 0.4222 0.165 0.014 0.017 0.062 0.4444 0.165 0.014 0.017 0.062 0.4667 0.165 0.015 0.017 0.062 0.4889 0. 165 0.016 0.018 0.062 0.5111 0.165 0.016 0.018 0. 062 0.5333 0.165 0.017 0.018 0.062 0.5556 0.165 0.018 0.018 0.062 0.5778 0.165 0.019 0.018 0.062 E-3 0.6000 0.165 0.020 0. 018 0.062 0.6222 0. 165 0.021 0.018 0.062 0.6444 0.165 0.022 0.018 0.062 0.6667 0.165 0.023 0.019 0.062 0.6889 0.165 0.025 0.019 0.062 0.7111 0.165 0.026 0.019 0.062 0.7333 0.165 0.027 0.019 0.062 0.7556 0.165 0.028 0.019 0. 062 0.7778 0.165 0.030 0. 019 0.062 0.8000 0.165 0.031 0. 019 0.062 0.8222 0.165 0.032 0.019 0.062 0.8444 0.165 0.033 0.020 0.062 0.8667 0.165 0.034 0. 020 0.062 0.8889 0.165 0.036 0. 020 0.062 0. 9111 0.165 0.037 0.020 0.062 0. 9333 0.165 0.038 0.020 0.062 0.9556 0.165 0.039 0. 020 0.062 0.9778 0. 165 0.040 0. 020 0.062 1.0000 0. 165 0.044 0. 020 0.062 1.0222 0. 165 0.048 0.037 0.062 1.0444 0.165 0.051 0. 066 0.062 1.0667 0.165 0.055 0.105 0.062 1.0889 0.165 0.059 0. 150 0.062 1.1111 0.165 0.062 0.201 0.062 1.1333 0.165 0.066 0.258 0.062 1. 1556 0.165 0.070 0.320 0.062 1.1778 0.165 0.073 0.386 0.062 1.2000 0.165 0.077 0.457 0. 062 1.2222 0.165 0.081 0.532 0.062 1.2444 0.165 0.085 0.610 0.062 1.2667 0.165 0.088 0.692 0.062 1.2889 0.165 0.092 0.778 0.062 1.3111 0.165 0.096 0.867 0.062 1.3333 0.165 0:099 0. 959 0.062 1.3556 0.165 0. 103 1.055 0.062 1.3778 0.165 0.107 1.153 0.062 1.4000 0. 165 0.110 1.254 0.062 1.4222 0.165 0.114 1.359 0.062 1.4444 0.165 0.118 1.465 0.062 1.4667 0.165 0.121 1.575 0.062 1.4889 0.165 0.125 1.687 0.062 1.5111 0.165 0.129 1.802 0.062 1.5333 0.165 0. 132 1. 920 0.062 1.5556 0.165 0.136 2.040 0.062 1.5778 0.165 0.140 2.162 0.062 1.6000 0.165 0.143 2.287 0.062 1.6222 0.165 0.147 2.413 0.062 1.6444 0.165 0.151 2 .543 0.062 1.6667 0.165 0.154 2 .674 0.062 1.6889 0.165 0.158 2 .808 0.062 1.7111 0.165 0.162 2 .944 0.062 1.7333 0.165 0. 165 3 .082 0.062 1.7556 0.165 0.169 3.222 0.062 1.7778 0.165 0.173 3 .364 0.062 1.8000 0.165 0.176 3.509 0.062 1.8222 0.165 0.180 3.655 0.062 1.8444 0.165 0.184 3 .803 0.062 E-4 1.8667 0.165 0.187 3. 953 0.062 1.8889 0.165 0.191 4.106 0. 062 1.9111 0.165 0.195 4 .260 0.062 1.9333 0.165 0.198 4 .416 0.062 1. 9556 0.165 0.202 4 .573 0.062 1. 9778 0.165 0.206 4 .733 0.062 2. 0000 0.165 0.209 4 .895 0.062 ANALYSIS RESULTS Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.032803 5 year 0.047834 10 year 0.059723 25 year 0.07716 50 year 0.092044 100 year 0.108675 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.015558 5 year 0.016347 10 year 0.016839 25 year 0.017433 50 year 0.017857 100 year 0.018268 Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1956 0. 151 0.018 1957 0.031 0.016 1958 0.043 0.016 1959 0.056 0.016 1960 0.037 0.015 1961 0.042 0.015 1962 0.036 0.015 1963 0.031 0.015 1964 0.025 0. 015 1965 0.015 0.015 1966 0.084 0.017 1967 0.038 0.016 1968 0.032 0.015 1969 0.029 0.015 1970 0.034 0.015 1971 0.045 0.016 1972 0.038 0.016 1973 0.035 0.015 1974 0.045 0.016 1975 0.032 0.016 1976 0.040 0.016 1977 0.025 0.015 1978 0.027 0.016 E-5 1979 0.032 0.015 1980 0.030 0. 015 1981 0.025 0.015 1982 0.026 0.015 1983 0.058 0.019 1984 0.016 0.015 1985 0.023 0.016 1986 0.032 0.015 1987 0.031 0.016 1988 0.025 0. 015 1989 0.015 0. 015 1990 0. 019 0.015 1991 0.038 0.017 1992 0.036 0.015 1993 0.024 0.015 1994 0.058 0.018 1995 0.034 0.015 1996 0.036 0.015 1997 0.035 0.015 1998 0.033 0.015 1999 0.061 0.018 Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0. 1511 0.0191 2 0. 0839 0.0180 3 0. 0614 0.0176 4 0. 0584 0.0176 5 0.0583 0.0168 6 0.0564 0.0166 7 0.0453 0.0164 8 0.0451 0.0163 9 0.0432 0.0160 10 0.0419 0.0159 11 0.0396 0.0158 12 0.0384 0. 0158 13 0.0384 0. 0157 14 0. 0379 0.0157 15 0.0374 0.0157 16 0. 0363 0.0156 17 0.0359 0.0156 18 0.0357 0.0155 19 0.0350 0 .0155 20 0.0346 0.0154 21 0.0345 0.0154 22 0.0337 0.0154 23 0.0335 0.0154 24 0. 0324 0.0154 25 0. 0323 0. 0153 26 0.0321 0.0153 27 0.0319 0.0153 28 0.0314 0.0152 29 0.0312 0.0152 30 0.0309 0.0152 31 0.0304 0.0152 32 0.0287 0.0152 E-6 33 0.0268 0.0151 34 0.0263 0.0151 35 0.0254 0.0151 36 0.0252 0.0151 37 0.0252 0.0151 38 0.0247 0.0150 39 0.0239 0.0150 40 0.0226 0.0150 41 0.0188 0.0149 42 0.0162 0.0149 43 0.0155 0.0149 44 0.0155 0.0149 POC #1 The Facility PASSED The Facility PASSED. Flow(cfs) Predev Mit Percentage Pass/Fail 0.0164 3055 27 0 Pass 0. 0172 2728 14 0 Pass 0. 0179 2441 7 0 Pass 0.0187 2178 3 0 Pass 0.0195 1926 0 0 Pass 0.0202 1703 0 0 Pass 0.0210 1492 0 0 Pass 0. 0217 1313 0 0 Pass 0.0225 1160 0 0 Pass 0.0233 1033 0 0 Pass 0. 0240 904 0 0 Pass 0. 0248 800 0 0 Pass 0.0256 682 0 0 Pass 0.0263 589 0 0 Pass 0.0271 509 0 0 Pass 0.0279 443 0 0 Pass 0.0286 382 0 0 Pass 0.0294 333 0 0 Pass 0.0302 288 0 0 Pass 0.0309 244 0 0 Pass 0.0317 211 0 0 Pass 0.0324 181 0 0 Pass 0.0332 157 0 0 Pass 0.0340 132 0 0 Pass 0.0347 118 0 0 Pass 0. 0355 107 0 0 Pass 0.0363 94 0 0 Pass 0.0370 84 0 0 Pass 0.0378 77 0 0 Pass 0.0386 66 0 0 Pass 0.0393 61 0 0 Pass 0.0401 55 0 0 Pass 0.0409 52 0 0 Pass 0.0416 46 0 0 Pass 0.0424 43 0 0 Pass 0.0431 40 0 0 Pass 0.0439 34 0 0 Pass E-7 0.0447 33 0 0 Pass 0. 0454 28 0 0 Pass 0.0462 28 0 0 Pass 0.0470 27 0 0 Pass 0.0477 21 0 0 Pass 0.0485 19 0 0 Pass 0. 0493 17 0 0 Pass 0. 0500 14 0 0 Pass 0.0508 12 0 0 Pass 0.0515 11 0 0 Pass 0.0523 11 0 0 Pass 0.0531 10 0 0 Pass 0.0538 6 0 0 Pass 0.0546 6 0 0 Pass 0.0554 6 0 0 Pass 0.0561 6 0 0 Pass 0.0569 5 0 0 Pass 0.0577 5 0 0 Pass 0.0584 3 0 0 Pass 0.0592 3 0 0 Pass 0.0600 3 0 0 Pass 0.0607 3 0 0 Pass 0.0615 2 0 0 Pass 0.0622 2 0 0 Pass 0. 0630 2 0 0 Pass 0. 0638 2 0 0 Pass 0. 0645 2 0 0 Pass 0.0653 2 0 0 Pass 0.0661 2 0 0 Pass 0.0668 2 0 0 Pass 0. 0676 2 0 0 Pass 0. 0684 2 0 0 Pass 0. 0691 2 0 0 Pass 0.0699 2 0 0 Pass 0.0707 2 0 0 Pass 0.0714 2 0 0 Pass 0.0722 2 0 0 Pass 0.0729 2 0 0 Pass 0.0737 2 0 0 Pass 0.0745 2 0 0 Pass 0.0752 2 0 0 Pass 0.0760 2 0 0 Pass 0.0768 2 0 0 Pass 0.0775 2 0 0 Pass 0.0783 2 0 0 Pass 0.0791 2 0 0 Pass 0.0798 2 0 0 Pass 0.0806 2 0 0 Pass 0.0813 2 0 0 Pass 0.0821 2 0 0 Pass 0.0829 2 0 0 Pass 0. 0836 2 0 0 Pass 0.0844 1 0 0 Pass 0.0852 1 0 0 Pass 0.0859 1 0 0 Pass 0.0867 1 0 0 Pass 0.0875 1 0 0 Pass E-8 0.0882 1 0 0 Pass 0.0890 1 0 0 Pass 0.0898 1 0 0 Pass 0.0905 1 0 0 Pass 0.0913 1 0 0 Pass 0.0920 1 0 0 Pass Water Quality BMP Flow and Volume for POC #1 On-line facility volume: 0.0552 acre-feet On-line facility target flow: 0.01 cfs. Adjusted for 15 min: 0.0608 cfs. Off-line facility target flow: 0. 0322 cfs. Adjusted for 15 min: 0.0355 cfs. Gravel trench bed infiltration rate = 0.062 cfs (> than off-line, 15-min. min. ) Perind and Impind Changes No changes have been made. This program and accompanying documentation is providedIas-is' without warranty of any kind. The entire risk regarding the performance and results of this program is assumed by the user. Clear Creek Solutions, Inc. disclaims all warranties, either expressed or implied, including but not limited to implied warranties of program and accompanying documentation. In no event shall Clear Creek Solutions, Inc. be liable for any damages whatsoever (including without limitation to damages for loss of business profits, loss of business information, business interruption, and the like) arising out of the use of, or inability to use this program even if Clear Creek Solutions, Inc. has been advised of the possibility of such damages. STAGE GRAPH 2.00 1.50 0.51 o �Op o 0. 10E-4 10E-3 10E-2 10E-1 1 10 100 (0.0o01) (OMI) (0.01) (D.1) F�rc�rbt Tirn� Exc-n�dirvp E-9 STAGE REPORT Facility No. 1003 "Gravel Trench Bed 1" Stage Occurances (feet) (hours in 40-years) 0.0100 2494 0.0301 335 0.0502 223 0.0703 150 0.0904 117 0.1105 87 0.1306 73 0.1507 55 0.1708 45 0.1909 39 0.2110 32 0.2311 29 0.2512 25 0.2713 22 0.2914 19 0.3115 17 0.3316 16 0.3517 16 0.3718 14 0.3919 13 0.4120 13 0.4321 10 0.4522 7 0.4723 7 0.4924 6 0.5125 6 0.5326 4 0.5527 4 0.5728 4 0.5929 2 0.6130 2 0.6331 2 0.6532 2 <---PEAK STAGE 0.6733 0 0.6934 0 0.7135 0 0.7336 0 0.7537 0 0.7738 0 0.7939 0 0.8140 0 0.8341 0 0.8542 0 0.8743 0 0.8944 0 0.9145 0 0.9346 0 0.9547 0 0.9748 0 0.9949 0 1.0151 0 E-10