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HomeMy WebLinkAboutTIR-4130Page 1 1 Prepared by: September 10, 2020 Anstey Engineering CIVIL ENGINEERING/CONSULTING 8627 NE 180th Street Bothell, Washington 98011 Phone: (206) 303-7639 Fax: (425) 658-9203 E-mail: benansey@ansteyengineering.com STORM DRAINAGE TARGETED TECHNICAL INFORMATION REPORT BURNETT AVENUE NORTH and North 33rd Place on PARCEL # 3342102005 & 3342102010 Located at 3302 Burnett Avenue North Renton, WA 98055 PARCEL # 3342102005 & 3342102010 FOR: Sound Housing 800 5th Ave Suite101-500, Seattle, WA 98104 ph: (425) 312 3978 Page 2 2 Table of Contents Technical Information Report (TIR) Cover 1 Table of Contents 2 Project Overview 3 Conditions and Requirements Summary 3 1. Discharge at the natural location 3 2. Offsite Analysis 3 3. Flow Control Design 5 4. Conveyance Design 8 5. Erosion Control D Design 8 6.Special Reports and Studies 9 7.Other Permits 9 8. Water Quality Design 9 9. Flow Control BMPs 10 SPECIAL REQUIREMENTS 10 Appendix Soil Data 10&11 King County iMap of Sensitive Areas 12 Figure C.2.11.A Perforated Pipe Connection 13 WWHM Report Page 3 3 PROJECT OVERVIEW This storm drainage technical information report has been prepared to address the City of Renton site development and storm drainage requirements for the 2 underlying lots located at 3302 Burnett Avenue North on Tax parcels # 3342102005 & 3342102010 located at the Southeast corner of the intersection of N 33rd Place and Burnett Avenue North in Renton, WA. The Legal Description is: HILLMANS LK WA GRARDEN OF EDEN NO 1 &LOT 2 WITH THE WEST 5 FEET OF LOT 3 The proposed project is located at 3302 Burnett Avenue North, Renton, WA 98056. The total property is 10,710 square feet and there is an existing house of 2,100 square feet that is to be removed. The remainder of the property is grass and soil. The site slopes from southeast down to northwest at 5% +/-. The proposed project involves two new single-family residences with driveways off of the alley, alley paving, and new sidewalk curb and gutter on N 33rd Place and Burnett Ave N fronting the site. The total impervious area will amount to 7,390 square feet. All surface water will be collected and diverted to the existing stormwater sewer through perforated pipe connections for the new houses. Area Table: Pervious area Lot 1 = 5614.5sf -2,617sf = 2,997.5 sf pervious Pervious area Lot 2 = 5,099.5sf – 2475sf= 2,604.5 sf pervious Planter strip = 1,712sf pervious Total pervious = 7,314SF Proposed Impervious Areas: Lot 1 = House = 2,120 sf Walk = 132 sf Pervious concrete driveway = 365 sf Total Lot 1 Impervious = 2,617 sf Area Table: Lot 2 impervious = House = 2,500 sf Walk = 40sf + 158sf = 198 sf Pervious Concrete wheel-strip Driveway = 179sf Total LOT 2 Impervious area = 2,877sf ROW New Sidewalk = 1,000sf New Road AC = 325sf – 304sf Removed = 21sf net increase + 1,277sf Alley = 1298sf Total project Impervious = 7,792sf Page 4 4 There is an existing piped storm drainage system on N 33rd Place to the north of the site. There are single family residences to the east, and south of the parcel. Currently, the stormwater runoff flows towards the existing catch basins southeast corner of the intersection of N 33rd Place and Burnett Avenue North. As more than 5,000sf of impervious area is created the project requires Full Drainage Review per 1.1.2.3 of the 2014 Renton SWDM. A site location and sensitive areas map can be seen in the Appendix. This map shows that the site is not located near sensitive areas and displays that the runoff will travel north and west towards lake Washington. The site is smaller than 22,000 sf so BMP’s will be used to the extent possible to control stormwater runoff. Conditions and Requirements Summary The 9 core requirements and 5 Special requirements will be addressed in this TIR: CORE REQUIREMENT #1 DISCHARGE AT THE NATURAL LOCATION The flows on this site are kept dispersed and are allowed to continue to flow to the natural downhill flow path. The flows will drain to the roadside ditch of Burnett Avenue North as they do now. CORE REQUIREMENT #2 OFFSITE ANALYSIS This is an urban area and the properties are small and fully developed. There are no significant on or off site flows on this property. No downstream drainage problems were observed. See Level One Downstream Drainage Study below: Offsite Analysis – Level One Downstream Analysis Task 1. Study Area Definition and Maps The properties to the south, and east of this site are small single family residences, and do not discharge any significant amount of runoff onto this site. Burnett Avenue North to the west is lower than the site and North 33rd Place to the north does not drain onto the site. No other significant flows enter the site. No concentrated surface water runoff will be discharged off-site. There are no downstream effects anticipated from the proposed development. The downstream flowpath of stormwater runoff during very large storms is to flow west to the roadside ditch of Burnett Avenue North and north to Lake Washington. A site map and topographical map with downstream flow path can be found in the Appendix on page 13 per KC Imap. Downstream Flow Path Length A. Roadside Ditch and drainage system of Burnett Avenue North 0.2 5 miles Page 5 5 Task 2: Resource Review Using the King County iMap interactive tool, it was found that there are no immediate critical areas upstream or downstream of the property. In addition, the site is not on or near any wetlands. The iMap also confirmed that there are no mitigating rivers, floodplain issues, there are no adopted basin plans, and the water quality is listed as “Basic Water Quality Treatment.” Task 3: Field Inspection There are no reported problems to be investigated. The amount of space and soil types present on the property clearly support the flow control BMPs being implemented. There will not be any destruction of aquatic habitat on-site or downstream. The Site was visited on April 27, 2015 and a 1/4 mile downstream investigation was made. As there are no signs of surface flow no problems were identified. Task 4: Drainage System Description and Problem Descriptions For this small site limited infiltration using perforated pipe connections per Figure C.2.11.A will be used. The Perforated Pipe connections will drain to the existing storm drainage system of North 33rd Place which drains to the storm drainage system of Burnett Avenue South. No problems were observed with the downstream drainage system. The 24 inch ø storm drain in Burnett Avenue South drains north and west to Lake Washington at a slope of 3 to 8%. Manning’s formula gives a capacity of at least 42cfs. The Basin draining to Burnett Ave S is approximately 36 acres and would have a peak 100 year flow of approximately 16.8cfs per WWHM so there should not be any capacity concern. The Drainage system in N 33rd Place drains the south half of N 33rd Place and the block between N 33rd Place and N 33rd Street from Burnett Ave N to Park Avenue N with an area or about 4.3 acres. Per WWHM the runoff from this basin would be approximately 2.1 CFS for the 100 year storm and the 12”ø CP pipe @ 4.8% can pass 8.4 CFS so there should be no capacity problems. Task 5: Mitigation of Existing or Potential Problems There are no existing or potential drainage problems and / or water quality problems. CORE REQUIREMENT #3 FLOW CONTROL Proposed Site and Drainage Part A: Existing Site Hydrology The parcel has an existing house that will be demolished. The site is gently sloped with slopes of 5% +/-. The storm water runoff from the site currently disperses across the site and drains into the Page 6 6 roadside ditch of Burnett Avenue North. There does not appear to be any significant surface flow. There is no evidence of any other on-site flows going off-site. The site does not receive any significant off-site flows from the adjacent properties. The Burnett Avenue North does not have curbs, gutters or sidewalks. It has a roadside ditch which drains into an 18” CP culvert and then to a 24” CVPVC storm drain draining north. North 33rd Place has asphalt wedge curbs and catch basins which collect the road runoff and drain it to the Burnett Avenue North Drainage system through 12” CP. Part B: Developed Site Hydrology When the new houses are constructed they can use limited infiltration using perforated pipe connections to the existing storm drain in Burnett Avenue North per Figure C.2.11.A. The site has been designed to comply with the reduced impervious surface area as the house and drive are smaller than what could be built on the site. Per the PanGeo Geotechnical Report dated Jan 20, 2020 the soils on the site were found to be more of the Alderwood Class C type with a high winter water table which makes infiltration infeasible for flow control. Part C: Performance Standards Flow control BMPs are used on this site to control stormwater using Limited Infiltration using a Perforated Pipe Connection per Figure C.2.11.A., pervious pavement per C.2.7 and the reduced impervious area credit. This is a single family residence on a small lot and as such does not pose any significant threat for pollution. No pollution generating activities are planned. This is not a ‘High Use Site’. It is a single family residence. Part D: Flow Control System The Erosion and Sediment Control Plans along with the Site Plans include the locations of the flow control systems. In addition, cross-sections of the flow control BMPs can be found in the Appendix. BMPs were analyzed for their practicality and limited infiltration using a perforated pipe connection to the storm drainage system in Burnett Avenue North was selected along with pervious pavement, and the reduced impervious area credit as the only practical BMPs. Part E: Water Quality System The site will have less than 5,000sf of pollution generating surface. There-fore no water quality treatment is required. This is not a high use site. No additional facilities will be necessary. FLOW CONTROL BMPs Flow control BMPs are used on this site to control stormwater. See discussion below: Full Dispersion – Unable to achieve the minimum 100 feet of native vegetated flowpath. Therefore, full dispersion is not feasible. Full Infiltration – According to the attached soils information from the NRCS Web Soil Survey, the soils on the site are listed as Indianola Loamy Fine Sand, InC. Full infiltration is only allowed with medium sands, coarse sands, or cobbles. Additionally, the Page 7 7 infiltration test did not yield an infiltration rate to show otherwise. Therefore, full infiltration is not applicable. Since full dispersion or full infiltration of roof runoff is not feasible, one or more of the alternate BMPs (listed in C.1.3.1 A.3) must be applied to (or used to mitigate for) an impervious area equal to at least 10% of the lot for lot sizes up to 11,000 square feet. [Paraphrased from C.1.3.1 A.3]. Limited Infiltration – The soils on the site are specified as InC Indianola Loamy Fine Sand 75 feet of gravel trench per 1,000 square feet of impervious area. There is insufficient space for the minimum amount of gravel trench needed. Basic Dispersion – There is not the minimum 50 feet required space to implement splash blocks and rock pads. In addition, gravel filled trenches and sheet flow are not feasible due to the inability to achieve 25 feet of vegetated flowpath. Rain Garden – The use of a raingarden for stormwater mitigation is infeasible due to constraints of the site, as open-space on the lot is limited. Permeable Pavement – Permeable Pavement is proposed for the residence driveways and walks. Rainwater Harvesting – Rainwater harvesting methods would be fairly large and therefore difficult to site on the lot due to space constraints. The landscaped area that would receive irrigation is also fairly small. Considering the costs and benefits rainwater harvesting is not practical for this site. Vegetated Roof – A Vegetated roof is not proposed for this residence. Reduced Impervious Surface Credit – See calculation below for credited reduction. Since the site is classified as a Small Lot, impervious areas less than a norm of 4,000 s.f. are eligible for Reduced Impervious Surface Credit through the Restricted Footprint allowance per C.2.9.2 of the SWDM. Impervious Area Norm per Zoning 3267 sq.ft. Total Impervious Surface for lot 1 -2,617 sq.ft. Restricted Footprint Credit 650 sq.ft. for lot 1 Applying the credited Restricted Footprint area to the target impervious surface: Target Impervious Surface 2,617 sq.ft. Restricted Footprint Credit -650 sq.ft. Area to be Mitigated 1,967 sq.ft. We use pervious pavement for 365sf and the 650sf Restricted Footprint credit so we have mitigated more than 10% of the lot as required: 1,015sf vs 516,45 required Page 8 8 For Lot 2 Impervious Area Norm per Zoning 5100sf lot= 3267 sq.ft. per zoning Total Impervious Surface for lot 2 -2,877 sq.ft. Restricted Footprint Credit 390 sq.ft. for lot 2 Applying the credited Restricted Footprint area to the target impervious surface: Target Impervious Surface 2,877 sq.ft. Restricted Footprint Credit -390 sq.ft. Area to be Mitigated 2,437 sq.ft. We use pervious pavement for 179sf and the 390sf Restricted Footprint credit so we have mitigated 569sf or more than 10% of the lot as required: 569sf vs 510 required Since full dispersion, full infiltration, and additional BMPs have been ruled-out, a perforated pipe connection per C.2.11.A is specified to allow limited infiltration from stormwater runoff from the roof area. The perforated pipe connection will be in a 2’ by 10’ gravel trench. The cross-section of the perforated pipe can be seen in Figure 2 of the Appendix or Figure C.2.11.A. and COR Standard Plan 263.4. The pipe will then connect to the existing Catch Basin at the Southeast corner of N 33rd Place and Burnett Avenue North. As more than 5,000sf of impervious area is created ( 7,390sf) the project does require Full Drainage Review or flow control per 1.1.2.3 of the 2014 Renton SWDM but is exempt as the peak flow for the 100year peak is 0.154535 which is a less than 0.15csf increase (0.146488) from the pre-developed pasture peak of 0.008047 per WWHM. See WWHM Report attached. CORE REQUIREMENT #4 CONVEYANCE SYSTEM As the flows on this small site are kept dispersed and are minimal there are no conveyance systems needed. The roadside Ditch of Burnett Avenue will be filled and replaced with 107lf of 18” CPVC at 4.4% to match the existing pipe to the south. As we are not adding any flow to this pipe segment the capacity of the new pipe will be adequate to handle the existing flow. Core Requirement #5 EROSION AND SEDIMENT CONTROL Temporary ESC measures will be required as there will be disturbance of the soil to construct the driveway and house, and clearing of the site. All of the flows from the driveway and house will flow onto the lot so no adjacent properties will be affected. A silt fence around the construction area and construction entrance should be provided at a minimum. No special requirements are needed In order to prevent erosion and trap sediment within the project site, the following BMPs will be used approximately as shown on the ESC plan: • Clearing limits will be marked by fencing or other means on the ground. Page 9 9 • Tree protection will be used to mark the trees designated to be preserved and to maintain a barrier from construction equipment. • Topsoil will be stockpiled in a designated area to be reapplied after the completion of construction • A rocked construction entrance will be placed at the location of the driveway throughout construction. • Runoff will not be allowed to concentrate and no water will be allowed to point discharge. • Silt fencing will be placed along slope contours at the downslope limit of clearing. • Mulch will be spread over all cleared areas of the site when they are not being worked. Mulch will consist of air-dried straw and chipped site vegetation. CORE REQUIREMENT #6 MAINTENANCE AND OPERATION The Perforated Pipe Connection will require little maintenance. See attached Maintenance requirements Page 10 10 Perforated Pipe Connection Instructions: Page 11 11 Page 12 12 Page 13 13 Page 14 14 CORE REQUIREMENT #7 FINANCIAL GUARANTEES AND LIABILITY The property owner will be responsible to insure that the project is constructed to the approved plans and that the drainage does not cause any problems. CORE REQUIREMENT #8 WATER QUALITY New/Replaced PGS = walk and drive = 497sf Lot 1+173sf lot 2 = 670 New Road AC = 325sf + 1,277sf alley = 1,602 sf New sidewalk = 1000sf Total new PGS = 3,272 sf As less than 5,000sf of new pollution generating surface area will be created (3,272sf) no special water quality treatment is necessary. Core Requirement #9 FLOW CONTROL BMPS BMPs will be used to the extent feasible to control Stormwater on this site. See Discussion of BMPs in Requirement #3 Flow Control. The only BMPs practical for this small lot are the Pervious Pipe Connection per C.2.11.A, Restricted Footprint Credit, and Pervious Pavement. The roof downspouts will be routed through the pervious pipe connection trench to the piped drainage system in North 33rd Place per C.2.11.A. Pervious pavement will be used for the driveway and walks per C.2.7. SPECIAL REQUIREMENTS: Special Requirement #1: Other Adopted Requirements – None Known Special Requirement # 2: Flood Hazard Delineation – Not required, not in flood area Special Requirement #3: Flood Protection Facilities – Not required, not in flood area Special Requirement #4: Source Control – Not require this is a Single Family residential development Special Requirement #5: Oil Control – Not required this is not a high use site. Appendix: Figure 1:I Imap Pan Geo Geotechnical Report WWHM Reports Page 15 15 Imap of site Page 16 16 Page 17 17 Page 18 18 Page 19 19 King King County iMap Date: 8/11/2020 Notes: The information included on this map has been compiled by King County staff from a variety of sources and is subject to changewithout notice. King County makes no representations or warranties, express or implied, as to accuracy, completeness, timeliness,or rights to the use of such information. This document is not intended for use as a survey product. King County shall not be liablefor any general, special, indirect, incidental, or consequential damages including, but not limited to, lost revenues or lost profitsresulting from the use or misuse of the information contained on this map. Any sale of this map or information on this map isprohibited except by written permission of King County.± WWHM2012 PROJECT REPORT N 33rd Place Basin V2 9/9/2020 4:55:57 PM Page 2 General Model Information Project Name:N 33rd Place Basin V2 Site Name:Burnett Ave N Site Address:3302 Burnett Ave N City:Renton Report Date:9/9/2020 Gage:Seatac Data Start:1948/10/01 Data End:2009/09/30 Timestep:15 Minute Precip Scale:1.000 Version Date:2019/09/13 Version:4.2.17 POC Thresholds Low Flow Threshold for POC1:50 Percent of the 2 Year High Flow Threshold for POC1:50 Year N 33rd Place Basin V2 9/9/2020 4:55:57 PM Page 3 Landuse Basin Data Predeveloped Land Use Basin 1 Bypass:No GroundWater:No Pervious Land Use acre A B, Forest, Mod 8.2 Pervious Total 8.2 Impervious Land Use acre Impervious Total 0 Basin Total 8.2 Element Flows To: Surface Interflow Groundwater N 33rd Place Basin V2 9/9/2020 4:55:57 PM Page 4 Mitigated Land Use Basin 1 Bypass:No GroundWater:No Pervious Land Use acre C, Lawn, Flat 2 Pervious Total 2 Impervious Land Use acre ROADS MOD 4.1 ROOF TOPS FLAT 2.1 Impervious Total 6.2 Basin Total 8.2 Element Flows To: Surface Interflow Groundwater N 33rd Place Basin V2 9/9/2020 4:55:57 PM Page 5 Routing Elements Predeveloped Routing N 33rd Place Basin V2 9/9/2020 4:55:57 PM Page 6 Mitigated Routing N 33rd Place Basin V2 9/9/2020 4:55:57 PM Page 7 Analysis Results POC 1 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area:8.2 Total Impervious Area:0 Mitigated Landuse Totals for POC #1 Total Pervious Area:2 Total Impervious Area:6.2 Flow Frequency Method:Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.007112 5 year 0.011738 10 year 0.015849 25 year 0.022501 50 year 0.028703 100 year 0.036146 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 2.717075 5 year 3.49478 10 year 4.041657 25 year 4.77057 50 year 5.342024 100 year 5.938605 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1949 0.006 3.630 1950 0.017 3.570 1951 0.017 2.192 1952 0.006 1.723 1953 0.006 2.070 1954 0.006 2.191 1955 0.007 2.573 1956 0.007 2.305 1957 0.007 2.721 1958 0.007 2.218 N 33rd Place Basin V2 9/9/2020 4:56:33 PM Page 8 1959 0.007 2.320 1960 0.006 2.421 1961 0.007 2.286 1962 0.006 1.964 1963 0.006 2.385 1964 0.007 2.265 1965 0.006 2.800 1966 0.006 1.909 1967 0.006 3.221 1968 0.006 4.082 1969 0.006 2.562 1970 0.006 2.528 1971 0.007 3.057 1972 0.047 3.079 1973 0.006 1.876 1974 0.007 2.870 1975 0.007 2.940 1976 0.007 2.276 1977 0.005 2.223 1978 0.006 3.083 1979 0.006 3.867 1980 0.006 4.144 1981 0.006 2.693 1982 0.007 3.924 1983 0.006 3.102 1984 0.006 1.949 1985 0.007 2.617 1986 0.006 2.275 1987 0.006 3.529 1988 0.006 2.126 1989 0.007 3.308 1990 0.007 5.061 1991 0.015 4.163 1992 0.006 1.992 1993 0.005 2.207 1994 0.006 2.011 1995 0.006 2.412 1996 0.064 3.056 1997 0.007 2.554 1998 0.006 2.543 1999 0.015 5.625 2000 0.006 2.615 2001 0.007 3.009 2002 0.006 3.322 2003 0.006 3.183 2004 0.007 5.365 2005 0.006 2.199 2006 0.007 2.057 2007 0.095 5.068 2008 0.007 3.935 2009 0.007 3.605 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.0952 5.6252 2 0.0638 5.3649 3 0.0473 5.0680 N 33rd Place Basin V2 9/9/2020 4:56:33 PM Page 9 4 0.0173 5.0610 5 0.0171 4.1635 6 0.0149 4.1444 7 0.0148 4.0823 8 0.0073 3.9350 9 0.0066 3.9240 10 0.0066 3.8671 11 0.0066 3.6304 12 0.0066 3.6053 13 0.0066 3.5697 14 0.0066 3.5294 15 0.0066 3.3221 16 0.0066 3.3081 17 0.0066 3.2214 18 0.0066 3.1833 19 0.0066 3.1024 20 0.0066 3.0829 21 0.0066 3.0792 22 0.0065 3.0570 23 0.0065 3.0557 24 0.0065 3.0090 25 0.0065 2.9398 26 0.0065 2.8701 27 0.0065 2.8000 28 0.0065 2.7212 29 0.0065 2.6928 30 0.0065 2.6168 31 0.0065 2.6152 32 0.0064 2.5726 33 0.0064 2.5622 34 0.0064 2.5540 35 0.0064 2.5432 36 0.0064 2.5283 37 0.0064 2.4213 38 0.0064 2.4124 39 0.0064 2.3850 40 0.0064 2.3204 41 0.0064 2.3052 42 0.0064 2.2861 43 0.0064 2.2758 44 0.0064 2.2747 45 0.0064 2.2646 46 0.0064 2.2230 47 0.0063 2.2178 48 0.0063 2.2073 49 0.0063 2.1987 50 0.0062 2.1919 51 0.0062 2.1914 52 0.0062 2.1256 53 0.0062 2.0704 54 0.0062 2.0567 55 0.0062 2.0115 56 0.0061 1.9920 57 0.0061 1.9640 58 0.0058 1.9494 59 0.0055 1.9089 60 0.0052 1.8762 61 0.0051 1.7226 N 33rd Place Basin V2 9/9/2020 4:56:33 PM Page 10 N 33rd Place Basin V2 9/9/2020 4:56:33 PM Page 11 Duration Flows Flow(cfs)Predev Mit Percentage Pass/Fail 0.0036 2915 637600 21873 Fail 0.0038 2485 624339 25124 Fail 0.0041 2120 611934 28864 Fail 0.0043 1796 600384 33428 Fail 0.0046 1502 589261 39231 Fail 0.0048 1293 578995 44779 Fail 0.0051 1084 569156 52505 Fail 0.0053 849 559531 65904 Fail 0.0056 624 550548 88228 Fail 0.0058 476 541778 113818 Fail 0.0061 329 533437 162138 Fail 0.0064 189 525523 278054 Fail 0.0066 41 517823 1262982 Fail 0.0069 35 510337 1458105 Fail 0.0071 33 503278 1525084 Fail 0.0074 31 496220 1600709 Fail 0.0076 30 489590 1631966 Fail 0.0079 29 483173 1666113 Fail 0.0081 29 476970 1644724 Fail 0.0084 29 470981 1624072 Fail 0.0086 28 464993 1660689 Fail 0.0089 28 459431 1640825 Fail 0.0091 27 453870 1681000 Fail 0.0094 27 448523 1661196 Fail 0.0097 27 443390 1642185 Fail 0.0099 27 438257 1623174 Fail 0.0102 26 433337 1666680 Fail 0.0104 25 428845 1715380 Fail 0.0107 25 424140 1696560 Fail 0.0109 24 419434 1747641 Fail 0.0112 23 415370 1805956 Fail 0.0114 23 410879 1786430 Fail 0.0117 23 406815 1768760 Fail 0.0119 22 402965 1831659 Fail 0.0122 22 398901 1813186 Fail 0.0124 21 395265 1882214 Fail 0.0127 21 391415 1863880 Fail 0.0130 21 387993 1847585 Fail 0.0132 21 384571 1831290 Fail 0.0135 21 381148 1814990 Fail 0.0137 20 377726 1888630 Fail 0.0140 19 374304 1970021 Fail 0.0142 19 371310 1954263 Fail 0.0145 18 368101 2045005 Fail 0.0147 18 365107 2028372 Fail 0.0150 16 362112 2263200 Fail 0.0152 16 359118 2244487 Fail 0.0155 16 356337 2227106 Fail 0.0157 16 353557 2209731 Fail 0.0160 15 350776 2338506 Fail 0.0163 15 347996 2319973 Fail 0.0165 15 345429 2302860 Fail 0.0168 15 342862 2285746 Fail 0.0170 15 340296 2268640 Fail N 33rd Place Basin V2 9/9/2020 4:56:33 PM Page 12 0.0173 14 337943 2413878 Fail 0.0175 13 335590 2581461 Fail 0.0178 13 333024 2561723 Fail 0.0180 13 330885 2545269 Fail 0.0183 13 328532 2527169 Fail 0.0185 13 326179 2509069 Fail 0.0188 13 324040 2492615 Fail 0.0191 12 321901 2682508 Fail 0.0193 11 319763 2906936 Fail 0.0196 11 317624 2887490 Fail 0.0198 11 315485 2868045 Fail 0.0201 11 313560 2850545 Fail 0.0203 11 311635 2833045 Fail 0.0206 10 309710 3097100 Fail 0.0208 10 307785 3077850 Fail 0.0211 10 305860 3058600 Fail 0.0213 9 304149 3379433 Fail 0.0216 9 302224 3358044 Fail 0.0218 9 300513 3339033 Fail 0.0221 9 298588 3317644 Fail 0.0224 9 296877 3298633 Fail 0.0226 8 295165 3689562 Fail 0.0229 8 293454 3668175 Fail 0.0231 8 291957 3649462 Fail 0.0234 8 290460 3630750 Fail 0.0236 8 288749 3609362 Fail 0.0239 8 287252 3590650 Fail 0.0241 8 285754 3571925 Fail 0.0244 8 284257 3553212 Fail 0.0246 8 282760 3534500 Fail 0.0249 8 281263 3515787 Fail 0.0251 8 279766 3497075 Fail 0.0254 8 278268 3478350 Fail 0.0257 8 276985 3462312 Fail 0.0259 8 275702 3446275 Fail 0.0262 8 274204 3427550 Fail 0.0264 8 272921 3411512 Fail 0.0267 8 271638 3395475 Fail 0.0269 8 270354 3379425 Fail 0.0272 8 269071 3363387 Fail 0.0274 8 267788 3347350 Fail 0.0277 8 266504 3331300 Fail 0.0279 8 265435 3317937 Fail 0.0282 8 264152 3301900 Fail 0.0284 8 263082 3288525 Fail 0.0287 8 261799 3272487 Fail The development has an increase in flow durations from 1/2 Predeveloped 2 year flow to the 2 year flow or more than a 10% increase from the 2 year to the 50 year flow. The development has an increase in flow durations for more than 50% of the flows for the range of the duration analysis. N 33rd Place Basin V2 9/9/2020 4:56:33 PM Page 13 Water Quality Water Quality BMP Flow and Volume for POC #1 On-line facility volume:0 acre-feet On-line facility target flow:0 cfs. Adjusted for 15 min:0 cfs. Off-line facility target flow:0 cfs. Adjusted for 15 min:0 cfs. N 33rd Place Basin V2 9/9/2020 4:56:33 PM Page 14 LID Report N 33rd Place Basin V2 9/9/2020 4:56:59 PM Page 15 Model Default Modifications Total of 0 changes have been made. PERLND Changes No PERLND changes have been made. IMPLND Changes No IMPLND changes have been made. N 33rd Place Basin V2 9/9/2020 4:56:59 PM Page 16 Appendix Predeveloped Schematic N 33rd Place Basin V2 9/9/2020 4:57:00 PM Page 17 Mitigated Schematic N 33rd Place Basin V2 9/9/2020 4:57:01 PM Page 18 Predeveloped UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END 2009 09 30 RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 UNIT SYSTEM 1 END GLOBAL FILES <File> <Un#> <-----------File Name------------------------------>*** <-ID-> *** WDM 26 N 33rd Place Basin V2.wdm MESSU 25 PreN 33rd Place Basin V2.MES 27 PreN 33rd Place Basin V2.L61 28 PreN 33rd Place Basin V2.L62 30 POCN 33rd Place Basin V21.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 2 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 Basin 1 MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 END TIMESERIES END COPY GENER OPCODE # # OPCD *** END OPCODE PARM # # K *** END PARM END GENER PERLND GEN-INFO <PLS ><-------Name------->NBLKS Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 2 A/B, Forest, Mod 1 1 1 1 27 0 END GEN-INFO *** Section PWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC *** 2 0 0 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ***************************** PIVL PYR # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC ********* 2 0 0 4 0 0 0 0 0 0 0 0 0 1 9 END PRINT-INFO N 33rd Place Basin V2 9/9/2020 4:57:01 PM Page 19 PWAT-PARM1 <PLS > PWATER variable monthly parameter value flags *** # - # CSNO RTOP UZFG VCS VUZ VNN VIFW VIRC VLE INFC HWT *** 2 0 0 0 0 0 0 0 0 0 0 0 END PWAT-PARM1 PWAT-PARM2 <PLS > PWATER input info: Part 2 *** # - # ***FOREST LZSN INFILT LSUR SLSUR KVARY AGWRC 2 0 5 2 400 0.1 0.3 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 2 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 2 0.2 0.5 0.35 0 0.7 0.7 END PWAT-PARM4 PWAT-STATE1 <PLS > *** Initial conditions at start of simulation ran from 1990 to end of 1992 (pat 1-11-95) RUN 21 *** # - # *** CEPS SURS UZS IFWS LZS AGWS GWVS 2 0 0 0 0 3 1 0 END PWAT-STATE1 END PERLND IMPLND GEN-INFO <PLS ><-------Name-------> Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* END PRINT-INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** END IWAT-PARM1 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS END IWAT-STATE1 N 33rd Place Basin V2 9/9/2020 4:57:01 PM Page 20 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Basin 1*** PERLND 2 8.2 COPY 501 12 PERLND 2 8.2 COPY 501 13 ******Routing****** END SCHEMATIC NETWORK <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** COPY 501 OUTPUT MEAN 1 1 48.4 DISPLY 1 INPUT TIMSER 1 <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** END NETWORK RCHRES GEN-INFO RCHRES Name Nexits Unit Systems Printer *** # - #<------------------><---> User T-series Engl Metr LKFG *** in out *** END GEN-INFO *** Section RCHRES*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG *** END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ******************* PIVL PYR # - # HYDR ADCA CONS HEAT SED GQL OXRX NUTR PLNK PHCB PIVL PYR ********* END PRINT-INFO HYDR-PARM1 RCHRES Flags for each HYDR Section *** # - # VC A1 A2 A3 ODFVFG for each *** ODGTFG for each FUNCT for each FG FG FG FG possible exit *** possible exit possible exit * * * * * * * * * * * * * * *** END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** <------><--------><--------><--------><--------><--------><--------> *** END HYDR-PARM2 HYDR-INIT RCHRES Initial conditions for each HYDR section *** # - # *** VOL Initial value of COLIND Initial value of OUTDGT *** ac-ft for each possible exit for each possible exit <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> END HYDR-INIT END RCHRES SPEC-ACTIONS END SPEC-ACTIONS FTABLES END FTABLES EXT SOURCES <-Volume-> <Member> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # tem strg<-factor->strg <Name> # # <Name> # # *** WDM 2 PREC ENGL 1 PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1 IMPLND 1 999 EXTNL PREC N 33rd Place Basin V2 9/9/2020 4:57:01 PM Page 21 WDM 1 EVAP ENGL 0.76 PERLND 1 999 EXTNL PETINP WDM 1 EVAP ENGL 0.76 IMPLND 1 999 EXTNL PETINP END EXT SOURCES EXT TARGETS <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Volume-> <Member> Tsys Tgap Amd *** <Name> # <Name> # #<-factor->strg <Name> # <Name> tem strg strg*** COPY 501 OUTPUT MEAN 1 1 48.4 WDM 501 FLOW ENGL REPL END EXT TARGETS MASS-LINK <Volume> <-Grp> <-Member-><--Mult--> <Target> <-Grp> <-Member->*** <Name> <Name> # #<-factor-> <Name> <Name> # #*** MASS-LINK 12 PERLND PWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 12 MASS-LINK 13 PERLND PWATER IFWO 0.083333 COPY INPUT MEAN END MASS-LINK 13 END MASS-LINK END RUN N 33rd Place Basin V2 9/9/2020 4:57:01 PM Page 22 Mitigated UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END 2009 09 30 RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 UNIT SYSTEM 1 END GLOBAL FILES <File> <Un#> <-----------File Name------------------------------>*** <-ID-> *** WDM 26 N 33rd Place Basin V2.wdm MESSU 25 MitN 33rd Place Basin V2.MES 27 MitN 33rd Place Basin V2.L61 28 MitN 33rd Place Basin V2.L62 30 POCN 33rd Place Basin V21.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 16 IMPLND 2 IMPLND 4 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 Basin 1 MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 END TIMESERIES END COPY GENER OPCODE # # OPCD *** END OPCODE PARM # # K *** END PARM END GENER PERLND GEN-INFO <PLS ><-------Name------->NBLKS Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 16 C, Lawn, Flat 1 1 1 1 27 0 END GEN-INFO *** Section PWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC *** 16 0 0 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ***************************** PIVL PYR # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC ********* 16 0 0 4 0 0 0 0 0 0 0 0 0 1 9 N 33rd Place Basin V2 9/9/2020 4:57:01 PM Page 23 END PRINT-INFO PWAT-PARM1 <PLS > PWATER variable monthly parameter value flags *** # - # CSNO RTOP UZFG VCS VUZ VNN VIFW VIRC VLE INFC HWT *** 16 0 0 0 0 0 0 0 0 0 0 0 END PWAT-PARM1 PWAT-PARM2 <PLS > PWATER input info: Part 2 *** # - # ***FOREST LZSN INFILT LSUR SLSUR KVARY AGWRC 16 0 4.5 0.03 400 0.05 0.5 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 16 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 16 0.1 0.25 0.25 6 0.5 0.25 END PWAT-PARM4 PWAT-STATE1 <PLS > *** Initial conditions at start of simulation ran from 1990 to end of 1992 (pat 1-11-95) RUN 21 *** # - # *** CEPS SURS UZS IFWS LZS AGWS GWVS 16 0 0 0 0 2.5 1 0 END PWAT-STATE1 END PERLND IMPLND GEN-INFO <PLS ><-------Name-------> Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 2 ROADS/MOD 1 1 1 27 0 4 ROOF TOPS/FLAT 1 1 1 27 0 END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** 2 0 0 1 0 0 0 4 0 0 1 0 0 0 END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* 2 0 0 4 0 0 0 1 9 4 0 0 4 0 0 0 1 9 END PRINT-INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** 2 0 0 0 0 0 4 0 0 0 0 0 END IWAT-PARM1 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC 2 400 0.05 0.1 0.08 4 400 0.01 0.1 0.1 N 33rd Place Basin V2 9/9/2020 4:57:01 PM Page 24 END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN 2 0 0 4 0 0 END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 2 0 0 4 0 0 END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Basin 1*** PERLND 16 2 COPY 501 12 PERLND 16 2 COPY 501 13 IMPLND 2 4.1 COPY 501 15 IMPLND 4 2.1 COPY 501 15 ******Routing****** END SCHEMATIC NETWORK <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** COPY 501 OUTPUT MEAN 1 1 48.4 DISPLY 1 INPUT TIMSER 1 <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** END NETWORK RCHRES GEN-INFO RCHRES Name Nexits Unit Systems Printer *** # - #<------------------><---> User T-series Engl Metr LKFG *** in out *** END GEN-INFO *** Section RCHRES*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG *** END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ******************* PIVL PYR # - # HYDR ADCA CONS HEAT SED GQL OXRX NUTR PLNK PHCB PIVL PYR ********* END PRINT-INFO HYDR-PARM1 RCHRES Flags for each HYDR Section *** # - # VC A1 A2 A3 ODFVFG for each *** ODGTFG for each FUNCT for each FG FG FG FG possible exit *** possible exit possible exit * * * * * * * * * * * * * * *** END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** <------><--------><--------><--------><--------><--------><--------> *** END HYDR-PARM2 N 33rd Place Basin V2 9/9/2020 4:57:01 PM Page 25 HYDR-INIT RCHRES Initial conditions for each HYDR section *** # - # *** VOL Initial value of COLIND Initial value of OUTDGT *** ac-ft for each possible exit for each possible exit <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> END HYDR-INIT END RCHRES SPEC-ACTIONS END SPEC-ACTIONS FTABLES END FTABLES EXT SOURCES <-Volume-> <Member> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # tem strg<-factor->strg <Name> # # <Name> # # *** WDM 2 PREC ENGL 1 PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1 IMPLND 1 999 EXTNL PREC WDM 1 EVAP ENGL 0.76 PERLND 1 999 EXTNL PETINP WDM 1 EVAP ENGL 0.76 IMPLND 1 999 EXTNL PETINP END EXT SOURCES EXT TARGETS <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Volume-> <Member> Tsys Tgap Amd *** <Name> # <Name> # #<-factor->strg <Name> # <Name> tem strg strg*** COPY 1 OUTPUT MEAN 1 1 48.4 WDM 701 FLOW ENGL REPL COPY 501 OUTPUT MEAN 1 1 48.4 WDM 801 FLOW ENGL REPL END EXT TARGETS MASS-LINK <Volume> <-Grp> <-Member-><--Mult--> <Target> <-Grp> <-Member->*** <Name> <Name> # #<-factor-> <Name> <Name> # #*** MASS-LINK 12 PERLND PWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 12 MASS-LINK 13 PERLND PWATER IFWO 0.083333 COPY INPUT MEAN END MASS-LINK 13 MASS-LINK 15 IMPLND IWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 15 END MASS-LINK END RUN N 33rd Place Basin V2 9/9/2020 4:57:01 PM Page 26 Predeveloped HSPF Message File N 33rd Place Basin V2 9/9/2020 4:57:01 PM Page 27 Mitigated HSPF Message File N 33rd Place Basin V2 9/9/2020 4:57:01 PM Page 28 Disclaimer Legal Notice This program and accompanying documentation are provided 'as-is' without warranty of any kind. The entire risk regarding the performance and results of this program is assumed by End User. Clear Creek Solutions Inc. and the governmental licensee or sublicensees disclaim 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. or their authorized representatives have been advised of the possibility of such damages. Software Copyright © by : Clear Creek Solutions, Inc. 2005-2020; All Rights Reserved. Clear Creek Solutions, Inc. 6200 Capitol Blvd. Ste F Olympia, WA. 98501 Toll Free 1(866)943-0304 Local (360)943-0304 www.clearcreeksolutions.com WWHM2012 PROJECT REPORT Burnett Ave N Site 9/9/2020 4:42:06 PM Page 2 General Model Information Project Name:Burnett Ave N Site Site Name:Burnett Ave N Site Address:3302 Burnett Ave N City:Renton Report Date:9/9/2020 Gage:Seatac Data Start:1948/10/01 Data End:2009/09/30 Timestep:15 Minute Precip Scale:1.000 Version Date:2019/09/13 Version:4.2.17 POC Thresholds Low Flow Threshold for POC1:50 Percent of the 2 Year High Flow Threshold for POC1:50 Year Burnett Ave N Site 9/9/2020 4:42:06 PM Page 3 Landuse Basin Data Predeveloped Land Use Basin 1 Bypass:No GroundWater:No Pervious Land Use acre A B, Lawn, Flat 0.216 Pervious Total 0.216 Impervious Land Use acre ROOF TOPS FLAT 0.096 DRIVEWAYS FLAT 0.018 Impervious Total 0.114 Basin Total 0.33 Element Flows To: Surface Interflow Groundwater Burnett Ave N Site 9/9/2020 4:42:06 PM Page 4 Mitigated Land Use Basin 1 Bypass:No GroundWater:No Pervious Land Use acre A B, Lawn, Flat 0.157 Pervious Total 0.157 Impervious Land Use acre ROADS MOD 0.04 ROOF TOPS FLAT 0.1 DRIVEWAYS FLAT 0.013 SIDEWALKS FLAT 0.02 Impervious Total 0.173 Basin Total 0.33 Element Flows To: Surface Interflow Groundwater Burnett Ave N Site 9/9/2020 4:42:06 PM Page 5 Routing Elements Predeveloped Routing Burnett Ave N Site 9/9/2020 4:42:06 PM Page 6 Mitigated Routing Burnett Ave N Site 9/9/2020 4:42:06 PM Page 7 Analysis Results POC 1 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area:0.216 Total Impervious Area:0.114 Mitigated Landuse Totals for POC #1 Total Pervious Area:0.157 Total Impervious Area:0.173 Flow Frequency Method:Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.044595 5 year 0.059288 10 year 0.070322 25 year 0.085824 50 year 0.09856 100 year 0.112362 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.069053 5 year 0.088878 10 year 0.102826 25 year 0.121425 50 year 0.136011 100 year 0.151244 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1949 0.057 0.089 1950 0.066 0.094 1951 0.042 0.059 1952 0.031 0.048 1953 0.034 0.053 1954 0.038 0.057 1955 0.040 0.064 1956 0.039 0.060 1957 0.045 0.069 1958 0.036 0.057 Burnett Ave N Site 9/9/2020 4:43:31 PM Page 8 1959 0.037 0.059 1960 0.037 0.058 1961 0.038 0.058 1962 0.033 0.052 1963 0.038 0.059 1964 0.036 0.058 1965 0.048 0.072 1966 0.031 0.047 1967 0.063 0.085 1968 0.060 0.098 1969 0.042 0.065 1970 0.041 0.063 1971 0.048 0.076 1972 0.064 0.086 1973 0.030 0.048 1974 0.044 0.070 1975 0.051 0.079 1976 0.035 0.055 1977 0.037 0.058 1978 0.045 0.075 1979 0.062 0.098 1980 0.056 0.090 1981 0.045 0.070 1982 0.064 0.099 1983 0.052 0.081 1984 0.033 0.050 1985 0.045 0.069 1986 0.039 0.060 1987 0.061 0.094 1988 0.037 0.057 1989 0.046 0.078 1990 0.121 0.150 1991 0.073 0.105 1992 0.033 0.050 1993 0.028 0.048 1994 0.031 0.049 1995 0.040 0.062 1996 0.057 0.078 1997 0.047 0.068 1998 0.042 0.066 1999 0.086 0.136 2000 0.043 0.067 2001 0.047 0.076 2002 0.055 0.084 2003 0.044 0.072 2004 0.081 0.129 2005 0.037 0.056 2006 0.037 0.054 2007 0.121 0.144 2008 0.072 0.100 2009 0.056 0.089 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.1210 0.1501 2 0.1205 0.1437 3 0.0863 0.1362 Burnett Ave N Site 9/9/2020 4:43:31 PM Page 9 4 0.0808 0.1287 5 0.0733 0.1054 6 0.0722 0.1001 7 0.0658 0.0991 8 0.0641 0.0985 9 0.0636 0.0977 10 0.0629 0.0944 11 0.0619 0.0936 12 0.0606 0.0896 13 0.0604 0.0894 14 0.0573 0.0889 15 0.0566 0.0861 16 0.0562 0.0848 17 0.0556 0.0838 18 0.0551 0.0810 19 0.0521 0.0788 20 0.0508 0.0779 21 0.0483 0.0777 22 0.0477 0.0760 23 0.0472 0.0756 24 0.0468 0.0745 25 0.0460 0.0719 26 0.0454 0.0719 27 0.0453 0.0700 28 0.0452 0.0697 29 0.0448 0.0690 30 0.0441 0.0689 31 0.0441 0.0679 32 0.0433 0.0667 33 0.0422 0.0658 34 0.0420 0.0645 35 0.0416 0.0638 36 0.0405 0.0634 37 0.0403 0.0624 38 0.0401 0.0605 39 0.0395 0.0604 40 0.0393 0.0593 41 0.0382 0.0590 42 0.0382 0.0590 43 0.0377 0.0580 44 0.0375 0.0579 45 0.0371 0.0577 46 0.0370 0.0577 47 0.0370 0.0571 48 0.0369 0.0570 49 0.0368 0.0566 50 0.0363 0.0564 51 0.0361 0.0549 52 0.0346 0.0541 53 0.0338 0.0533 54 0.0333 0.0516 55 0.0331 0.0503 56 0.0326 0.0501 57 0.0314 0.0494 58 0.0310 0.0481 59 0.0308 0.0480 60 0.0302 0.0476 61 0.0282 0.0472 Burnett Ave N Site 9/9/2020 4:43:31 PM Page 10 Burnett Ave N Site 9/9/2020 4:43:31 PM Page 11 Duration Flows Flow(cfs)Predev Mit Percentage Pass/Fail 0.0223 1709 6363 372 Fail 0.0231 1503 5833 388 Fail 0.0238 1344 5341 397 Fail 0.0246 1182 4855 410 Fail 0.0254 1052 4434 421 Fail 0.0261 946 4040 427 Fail 0.0269 862 3696 428 Fail 0.0277 773 3416 441 Fail 0.0285 693 3131 451 Fail 0.0292 632 2890 457 Fail 0.0300 578 2650 458 Fail 0.0308 524 2434 464 Fail 0.0315 471 2259 479 Fail 0.0323 433 2058 475 Fail 0.0331 411 1901 462 Fail 0.0339 378 1759 465 Fail 0.0346 351 1634 465 Fail 0.0354 323 1506 466 Fail 0.0362 296 1384 467 Fail 0.0369 276 1281 464 Fail 0.0377 247 1195 483 Fail 0.0385 230 1106 480 Fail 0.0392 208 1030 495 Fail 0.0400 192 953 496 Fail 0.0408 173 879 508 Fail 0.0416 161 829 514 Fail 0.0423 149 777 521 Fail 0.0431 138 719 521 Fail 0.0439 130 666 512 Fail 0.0446 124 633 510 Fail 0.0454 115 596 518 Fail 0.0462 108 559 517 Fail 0.0469 103 523 507 Fail 0.0477 95 486 511 Fail 0.0485 86 455 529 Fail 0.0493 83 438 527 Fail 0.0500 80 410 512 Fail 0.0508 76 389 511 Fail 0.0516 73 376 515 Fail 0.0523 69 358 518 Fail 0.0531 64 340 531 Fail 0.0539 61 323 529 Fail 0.0547 54 308 570 Fail 0.0554 49 280 571 Fail 0.0562 46 269 584 Fail 0.0570 42 249 592 Fail 0.0577 40 237 592 Fail 0.0585 37 224 605 Fail 0.0593 35 207 591 Fail 0.0600 33 198 600 Fail 0.0608 29 182 627 Fail 0.0616 26 179 688 Fail 0.0624 22 166 754 Fail 0.0631 21 160 761 Fail Burnett Ave N Site 9/9/2020 4:43:31 PM Page 12 0.0639 20 153 765 Fail 0.0647 19 146 768 Fail 0.0654 18 142 788 Fail 0.0662 16 134 837 Fail 0.0670 15 128 853 Fail 0.0677 15 125 833 Fail 0.0685 15 117 780 Fail 0.0693 15 113 753 Fail 0.0701 15 105 700 Fail 0.0708 15 104 693 Fail 0.0716 15 99 660 Fail 0.0724 13 92 707 Fail 0.0731 13 86 661 Fail 0.0739 12 86 716 Fail 0.0747 11 84 763 Fail 0.0755 11 80 727 Fail 0.0762 10 72 720 Fail 0.0770 9 70 777 Fail 0.0778 9 68 755 Fail 0.0785 9 65 722 Fail 0.0793 7 61 871 Fail 0.0801 7 61 871 Fail 0.0808 5 60 1200 Fail 0.0816 5 58 1160 Fail 0.0824 5 55 1100 Fail 0.0832 5 49 980 Fail 0.0839 5 47 939 Fail 0.0847 5 44 880 Fail 0.0855 4 42 1050 Fail 0.0862 4 36 900 Fail 0.0870 3 35 1166 Fail 0.0878 3 35 1166 Fail 0.0885 3 34 1133 Fail 0.0893 3 31 1033 Fail 0.0901 3 28 933 Fail 0.0909 3 25 833 Fail 0.0916 3 23 766 Fail 0.0924 3 23 766 Fail 0.0932 3 23 766 Fail 0.0939 3 21 700 Fail 0.0947 3 20 666 Fail 0.0955 3 20 666 Fail 0.0962 3 20 666 Fail 0.0970 3 20 666 Fail 0.0978 2 19 950 Fail 0.0986 2 17 850 Fail The development has an increase in flow durations from 1/2 Predeveloped 2 year flow to the 2 year flow or more than a 10% increase from the 2 year to the 50 year flow. The development has an increase in flow durations for more than 50% of the flows for the range of the duration analysis. Burnett Ave N Site 9/9/2020 4:43:31 PM Page 13 Water Quality Water Quality BMP Flow and Volume for POC #1 On-line facility volume:0 acre-feet On-line facility target flow:0 cfs. Adjusted for 15 min:0 cfs. Off-line facility target flow:0 cfs. Adjusted for 15 min:0 cfs. Burnett Ave N Site 9/9/2020 4:43:31 PM Page 14 LID Report Burnett Ave N Site 9/9/2020 4:44:01 PM Page 15 Model Default Modifications Total of 0 changes have been made. PERLND Changes No PERLND changes have been made. IMPLND Changes No IMPLND changes have been made. Burnett Ave N Site 9/9/2020 4:44:01 PM Page 16 Appendix Predeveloped Schematic Burnett Ave N Site 9/9/2020 4:44:02 PM Page 17 Mitigated Schematic Burnett Ave N Site 9/9/2020 4:44:03 PM Page 18 Predeveloped UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END 2009 09 30 RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 UNIT SYSTEM 1 END GLOBAL FILES <File> <Un#> <-----------File Name------------------------------>*** <-ID-> *** WDM 26 Burnett Ave N Site.wdm MESSU 25 PreBurnett Ave N Site.MES 27 PreBurnett Ave N Site.L61 28 PreBurnett Ave N Site.L62 30 POCBurnett Ave N Site1.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 7 IMPLND 4 IMPLND 5 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 Basin 1 MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 END TIMESERIES END COPY GENER OPCODE # # OPCD *** END OPCODE PARM # # K *** END PARM END GENER PERLND GEN-INFO <PLS ><-------Name------->NBLKS Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 7 A/B, Lawn, Flat 1 1 1 1 27 0 END GEN-INFO *** Section PWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC *** 7 0 0 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ***************************** PIVL PYR # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC ********* 7 0 0 4 0 0 0 0 0 0 0 0 0 1 9 Burnett Ave N Site 9/9/2020 4:44:03 PM Page 19 END PRINT-INFO PWAT-PARM1 <PLS > PWATER variable monthly parameter value flags *** # - # CSNO RTOP UZFG VCS VUZ VNN VIFW VIRC VLE INFC HWT *** 7 0 0 0 0 0 0 0 0 0 0 0 END PWAT-PARM1 PWAT-PARM2 <PLS > PWATER input info: Part 2 *** # - # ***FOREST LZSN INFILT LSUR SLSUR KVARY AGWRC 7 0 5 0.8 400 0.05 0.3 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 7 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 7 0.1 0.5 0.25 0 0.7 0.25 END PWAT-PARM4 PWAT-STATE1 <PLS > *** Initial conditions at start of simulation ran from 1990 to end of 1992 (pat 1-11-95) RUN 21 *** # - # *** CEPS SURS UZS IFWS LZS AGWS GWVS 7 0 0 0 0 3 1 0 END PWAT-STATE1 END PERLND IMPLND GEN-INFO <PLS ><-------Name-------> Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 4 ROOF TOPS/FLAT 1 1 1 27 0 5 DRIVEWAYS/FLAT 1 1 1 27 0 END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** 4 0 0 1 0 0 0 5 0 0 1 0 0 0 END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* 4 0 0 4 0 0 0 1 9 5 0 0 4 0 0 0 1 9 END PRINT-INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** 4 0 0 0 0 0 5 0 0 0 0 0 END IWAT-PARM1 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC 4 400 0.01 0.1 0.1 5 400 0.01 0.1 0.1 Burnett Ave N Site 9/9/2020 4:44:03 PM Page 20 END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN 4 0 0 5 0 0 END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 4 0 0 5 0 0 END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Basin 1*** PERLND 7 0.216 COPY 501 12 PERLND 7 0.216 COPY 501 13 IMPLND 4 0.096 COPY 501 15 IMPLND 5 0.018 COPY 501 15 ******Routing****** END SCHEMATIC NETWORK <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** COPY 501 OUTPUT MEAN 1 1 48.4 DISPLY 1 INPUT TIMSER 1 <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** END NETWORK RCHRES GEN-INFO RCHRES Name Nexits Unit Systems Printer *** # - #<------------------><---> User T-series Engl Metr LKFG *** in out *** END GEN-INFO *** Section RCHRES*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG *** END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ******************* PIVL PYR # - # HYDR ADCA CONS HEAT SED GQL OXRX NUTR PLNK PHCB PIVL PYR ********* END PRINT-INFO HYDR-PARM1 RCHRES Flags for each HYDR Section *** # - # VC A1 A2 A3 ODFVFG for each *** ODGTFG for each FUNCT for each FG FG FG FG possible exit *** possible exit possible exit * * * * * * * * * * * * * * *** END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** <------><--------><--------><--------><--------><--------><--------> *** END HYDR-PARM2 Burnett Ave N Site 9/9/2020 4:44:03 PM Page 21 HYDR-INIT RCHRES Initial conditions for each HYDR section *** # - # *** VOL Initial value of COLIND Initial value of OUTDGT *** ac-ft for each possible exit for each possible exit <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> END HYDR-INIT END RCHRES SPEC-ACTIONS END SPEC-ACTIONS FTABLES END FTABLES EXT SOURCES <-Volume-> <Member> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # tem strg<-factor->strg <Name> # # <Name> # # *** WDM 2 PREC ENGL 1 PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1 IMPLND 1 999 EXTNL PREC WDM 1 EVAP ENGL 0.76 PERLND 1 999 EXTNL PETINP WDM 1 EVAP ENGL 0.76 IMPLND 1 999 EXTNL PETINP END EXT SOURCES EXT TARGETS <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Volume-> <Member> Tsys Tgap Amd *** <Name> # <Name> # #<-factor->strg <Name> # <Name> tem strg strg*** COPY 501 OUTPUT MEAN 1 1 48.4 WDM 501 FLOW ENGL REPL END EXT TARGETS MASS-LINK <Volume> <-Grp> <-Member-><--Mult--> <Target> <-Grp> <-Member->*** <Name> <Name> # #<-factor-> <Name> <Name> # #*** MASS-LINK 12 PERLND PWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 12 MASS-LINK 13 PERLND PWATER IFWO 0.083333 COPY INPUT MEAN END MASS-LINK 13 MASS-LINK 15 IMPLND IWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 15 END MASS-LINK END RUN Burnett Ave N Site 9/9/2020 4:44:03 PM Page 22 Mitigated UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END 2009 09 30 RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 UNIT SYSTEM 1 END GLOBAL FILES <File> <Un#> <-----------File Name------------------------------>*** <-ID-> *** WDM 26 Burnett Ave N Site.wdm MESSU 25 MitBurnett Ave N Site.MES 27 MitBurnett Ave N Site.L61 28 MitBurnett Ave N Site.L62 30 POCBurnett Ave N Site1.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 7 IMPLND 2 IMPLND 4 IMPLND 5 IMPLND 8 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 Basin 1 MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 END TIMESERIES END COPY GENER OPCODE # # OPCD *** END OPCODE PARM # # K *** END PARM END GENER PERLND GEN-INFO <PLS ><-------Name------->NBLKS Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 7 A/B, Lawn, Flat 1 1 1 1 27 0 END GEN-INFO *** Section PWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC *** 7 0 0 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ***************************** PIVL PYR Burnett Ave N Site 9/9/2020 4:44:03 PM Page 23 # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC ********* 7 0 0 4 0 0 0 0 0 0 0 0 0 1 9 END PRINT-INFO PWAT-PARM1 <PLS > PWATER variable monthly parameter value flags *** # - # CSNO RTOP UZFG VCS VUZ VNN VIFW VIRC VLE INFC HWT *** 7 0 0 0 0 0 0 0 0 0 0 0 END PWAT-PARM1 PWAT-PARM2 <PLS > PWATER input info: Part 2 *** # - # ***FOREST LZSN INFILT LSUR SLSUR KVARY AGWRC 7 0 5 0.8 400 0.05 0.3 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 7 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 7 0.1 0.5 0.25 0 0.7 0.25 END PWAT-PARM4 PWAT-STATE1 <PLS > *** Initial conditions at start of simulation ran from 1990 to end of 1992 (pat 1-11-95) RUN 21 *** # - # *** CEPS SURS UZS IFWS LZS AGWS GWVS 7 0 0 0 0 3 1 0 END PWAT-STATE1 END PERLND IMPLND GEN-INFO <PLS ><-------Name-------> Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 2 ROADS/MOD 1 1 1 27 0 4 ROOF TOPS/FLAT 1 1 1 27 0 5 DRIVEWAYS/FLAT 1 1 1 27 0 8 SIDEWALKS/FLAT 1 1 1 27 0 END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** 2 0 0 1 0 0 0 4 0 0 1 0 0 0 5 0 0 1 0 0 0 8 0 0 1 0 0 0 END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* 2 0 0 4 0 0 0 1 9 4 0 0 4 0 0 0 1 9 5 0 0 4 0 0 0 1 9 8 0 0 4 0 0 0 1 9 END PRINT-INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** 2 0 0 0 0 0 Burnett Ave N Site 9/9/2020 4:44:03 PM Page 24 4 0 0 0 0 0 5 0 0 0 0 0 8 0 0 0 0 0 END IWAT-PARM1 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC 2 400 0.05 0.1 0.08 4 400 0.01 0.1 0.1 5 400 0.01 0.1 0.1 8 400 0.01 0.1 0.1 END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN 2 0 0 4 0 0 5 0 0 8 0 0 END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 2 0 0 4 0 0 5 0 0 8 0 0 END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Basin 1*** PERLND 7 0.157 COPY 501 12 PERLND 7 0.157 COPY 501 13 IMPLND 2 0.04 COPY 501 15 IMPLND 4 0.1 COPY 501 15 IMPLND 5 0.013 COPY 501 15 IMPLND 8 0.02 COPY 501 15 ******Routing****** END SCHEMATIC NETWORK <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** COPY 501 OUTPUT MEAN 1 1 48.4 DISPLY 1 INPUT TIMSER 1 <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** END NETWORK RCHRES GEN-INFO RCHRES Name Nexits Unit Systems Printer *** # - #<------------------><---> User T-series Engl Metr LKFG *** in out *** END GEN-INFO *** Section RCHRES*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG *** Burnett Ave N Site 9/9/2020 4:44:03 PM Page 25 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ******************* PIVL PYR # - # HYDR ADCA CONS HEAT SED GQL OXRX NUTR PLNK PHCB PIVL PYR ********* END PRINT-INFO HYDR-PARM1 RCHRES Flags for each HYDR Section *** # - # VC A1 A2 A3 ODFVFG for each *** ODGTFG for each FUNCT for each FG FG FG FG possible exit *** possible exit possible exit * * * * * * * * * * * * * * *** END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** <------><--------><--------><--------><--------><--------><--------> *** END HYDR-PARM2 HYDR-INIT RCHRES Initial conditions for each HYDR section *** # - # *** VOL Initial value of COLIND Initial value of OUTDGT *** ac-ft for each possible exit for each possible exit <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> END HYDR-INIT END RCHRES SPEC-ACTIONS END SPEC-ACTIONS FTABLES END FTABLES EXT SOURCES <-Volume-> <Member> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # tem strg<-factor->strg <Name> # # <Name> # # *** WDM 2 PREC ENGL 1 PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1 IMPLND 1 999 EXTNL PREC WDM 1 EVAP ENGL 0.76 PERLND 1 999 EXTNL PETINP WDM 1 EVAP ENGL 0.76 IMPLND 1 999 EXTNL PETINP END EXT SOURCES EXT TARGETS <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Volume-> <Member> Tsys Tgap Amd *** <Name> # <Name> # #<-factor->strg <Name> # <Name> tem strg strg*** COPY 1 OUTPUT MEAN 1 1 48.4 WDM 701 FLOW ENGL REPL COPY 501 OUTPUT MEAN 1 1 48.4 WDM 801 FLOW ENGL REPL END EXT TARGETS MASS-LINK <Volume> <-Grp> <-Member-><--Mult--> <Target> <-Grp> <-Member->*** <Name> <Name> # #<-factor-> <Name> <Name> # #*** MASS-LINK 12 PERLND PWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 12 MASS-LINK 13 PERLND PWATER IFWO 0.083333 COPY INPUT MEAN END MASS-LINK 13 MASS-LINK 15 IMPLND IWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 15 END MASS-LINK END RUN Burnett Ave N Site 9/9/2020 4:44:03 PM Page 26 Predeveloped HSPF Message File Burnett Ave N Site 9/9/2020 4:44:03 PM Page 27 Mitigated HSPF Message File Burnett Ave N Site 9/9/2020 4:44:03 PM Page 28 Disclaimer Legal Notice This program and accompanying documentation are provided 'as-is' without warranty of any kind. The entire risk regarding the performance and results of this program is assumed by End User. Clear Creek Solutions Inc. and the governmental licensee or sublicensees disclaim 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. or their authorized representatives have been advised of the possibility of such damages. Software Copyright © by : Clear Creek Solutions, Inc. 2005-2020; All Rights Reserved. Clear Creek Solutions, Inc. 6200 Capitol Blvd. Ste F Olympia, WA. 98501 Toll Free 1(866)943-0304 Local (360)943-0304 www.clearcreeksolutions.com ________________________________________________ 3213 Eastlake Ave E Ste B Seattle, WA 98102 T. (206) 262-0370 F. (206) 262-0374 Geotechnical & Earthquake Engineering Consultants August 25, 2016 Revised on January 30, 2020 File No. 16-204 Ms. Tatiana Gershanovich Sound Housing, LLC 8005 5th Ave, Suite 101-500 Seattle, WA 98104 Subject: Geotechnical Evaluation for Stormwater Drainage Design Proposed Short-Plat and Development 3302 Burnett Avenue North, Renton, Washington Dear Ms. Gershanovich, As requested, PanGEO completed a geotechnical evaluation to assist you with the stormwater drainage design at the above referenced property. We understand that the proposed development consists of subdividing the property into two single-family residential lots, and to construct one single family residence on each subdivided lot (see Figures 1 and 2). We also understand that the current stormwater drainage design includes a ten-foot long perforated pipe which will be connected to an existing catch basin in the city right of way for each parcel. We further understand that a geotechnical evaluation is required by the City of Renton to evaluate the groundwater and soil conditions for the proposed flow control and BMP design. Our service scope consisted of reviewing readily-available geologic and geotechnical data, observing excavations of three test pits, logging the soil conditions, and summarizing the test results. SUBSURFACE EXPLORATION AND CONDITIONS CURRENT EXPLORATION On July 10, 2016, three test pits were excavated at the subject property. The test pits were completed to the maximum depths of five to six feet below the existing ground surface. After each test pit was logged, the excavation was backfilled with the excavated soils and the surface was tamped and re-graded smooth. Geotechnical Evaluation for Stormwater Drainage Design Proposed Short-Plat and Development: 3302 Burnett Avenue N, Renton, WA Revised on January 30, 2020 16-204 3302 Burnett Ave N Rpt Rev01 PanGEO, Inc. 2 A geologist from PanGEO was present during the field exploration to observe the test pit excavations, obtain representative soil samples, and describe and document the subsurface conditions encountered. The system used to classify the soils is summarized on Figure A-1, Terms and Symbols for Boring and Test Pit Logs. The relative in-situ density of cohesionless soils, or the relative consistency of fine-grained soils, was estimated from the excavating action of the excavator, and the stability of the test pit sidewalls. Summary test pit logs are presented in Appendix A. The logs provide descriptions of the materials encountered, depths to soil contacts, and depths of seepage or caving, if present, observed in the test pit sidewalls. In general, the soils encountered at the test pit locations consisted of a surficial topsoil layer over approximately two feet of dense, grey-brown, silty sand with gravel (weathered till) which became very dense and cemented at depth (glacial till, or hardpan). No groundwater was present at the time of excavation. However, the contractor should also be aware that groundwater levels will fluctuate depending on the season, precipitation, and the surface water level in Lake Washington. Generally, the water level is higher and seepage rates are greater in the wetter, winter months (typically October through May). PREVIOUS EXPLORATIONS As part of our study, we also reviewed the results of previous explorations conducted in the project vicinity to gain an understanding of the subsurface conditions in the area. Specifically, the summary logs of test borings from the following previous explorations were reviewed: • Summary Test Borings B-10, B-23, and B-24, Hydrogeologic Report for Proposed Kennydale Tunnel, prepared by Robertson & Roberts, 1961 The approximate locations of these previous test borings and their summary logs are included in Appendix B for reference. In summary, the previous exploration encountered about 50 feet of glacial till at B-23 (the boring nearest the subject property) and B-24 (downslope from subject property), and about 10 feet of recessional outwash overlying 60 feet of glacial till at B-10 (upslope from subject property). Geotechnical Evaluation for Stormwater Drainage Design Proposed Short-Plat and Development: 3302 Burnett Avenue N, Renton, WA Revised on January 30, 2020 16-204 3302 Burnett Ave N Rpt Rev01 PanGEO, Inc. 3 OPTIONS AND CONCLUSIONS The subject property is underlain by glacial till (Hardpan) at shallow depths. As a result, stormwater disposal using infiltration is not feasible. Based on the Storm Drainage Small Site Technical Information Report (Anstey Engineering, 2015), the current drainage design consisted of a perforated pipe section in a minimum 2 feet wide and 10 feet long gravel trench at least 18 inches deep. The perforated pipe is connected to the existing catch basin in the right of way. Based on the surface and subsurface conditions at the site, the current drainage design is considered appropriate from a geotechnical engineering standpoint. It is also our opinion that the current drainage design will not have adverse impacts of the site stability of the subject and surrounding properties. LIMITATIONS We have prepared this report for use by Ms. Tatiana Gershanovich. Recommendations contained in this report are based on a site reconnaissance, a subsurface exploration program, review of pertinent subsurface information, and our understanding of the project. The study was performed using a mutually agreed-upon scope of work. This report may be used only by the client and for the purposes stated, within a reasonable time from its issuance. Land use, site conditions (both off and on-site), or other factors including advances in our understanding of applied science, may change over time and could materially affect our findings. Therefore, this report should not be relied upon after 24 months from its issuance. PanGEO should be notified if the project is delayed by more than 24 months from the date of this report so that we may review the applicability of our conclusions considering the time lapse. Within the limitation of scope, schedule and budget, PanGEO engages in the practice of geotechnical engineering and endeavors to perform its services in accordance with generally accepted professional principles and practices at the time the Report or its contents were prepared. No warranty, express or implied, is made. We appreciate the opportunity to be of service to you on this project. Please feel free to contact our office with any questions you have regarding our study, this report, or any geotechnical engineering related project issues. Geotechnical Evaluation for Stormwater Drainage Design Proposed Short-Plat and Development: 3302 Burnett Avenue N, Renton, WA Revised on January 30, 2020 16-204 3302 Burnett Ave N Rpt Rev01 PanGEO, Inc. 4 Sincerely, 12/30/2020 Bart Weitering, G.I.T. H. Michael Xue, P.E. Staff Geologist Principal Geotechnical Engineer Enclosures: Figure 1 Vicinity Map Figure 2 Site and Exploration Plan Appendix A: Summary Test Pit Logs Figure A-1 Terms and Symbols for Boring and Test Pit Logs Figure A-2 Log of Test Pit TP-1 Figure A-3 Log of Test Pit TP-2 Figure A-4 Log of Test Pit TP-3 Appendix B: Previous Subsurface Explorations Figure B-1 Previous Boring Locations Figure B-2 Cross Section with Logs of Borings B-10, B-23, and B-24 Geotechnical Evaluation for Stormwater Drainage Design Proposed Short-Plat and Development: 3302 Burnett Avenue N, Renton, WA Revised on January 30, 2020 16-204 3302 Burnett Ave N Rpt Rev01 PanGEO, Inc. 5 REFERENCES: Anstey Engineering, Storm Drainage Small Site Technical Information Report – Proposed Two Lot Short Plat Located at 3302 Burnett Avenue North, Renton, Washington 98055, November 25, 2015. City of Renton Department of Community and Economic Development Planning Division, Pre- Application Meeting Comments for 3302 Kennydale Short Plat, Pre 15-000530, July 30, 2015. Roberts & Robertson, Summary Test Pit Logs, B-10, B-23, and B-24, Hydrogeologic Report for Proposed Kennydale Tunnel, Burnett Avenue N, Renton, Washington, October 30, 1961. 16-204 Proposed Short-Plat and Development 3302 Burnett Avenue N Renton, Washington 1 VICINITY MAP BH-1 Figure No.Project No. Reference: Google Terrain Map Project Site Not to Scale Figure No.Project No.16-204 2 Proposed Short-Plat and Development 3302 Burnett Avenue N Renton, Washington SITE AND EXPLORATION PLAN Note: Basemap modified from Tree Replacement Plan by GHA Landscape Architects, stamp dated February 11, 2016. Approx. Scale 1" = 20' Test Pit Location Legend: Approx. Outline of Proposed Development PG-1 North Lot Middle Lot South Lot PIT-1 133rd Ave NE TP-1 TP-2 TP-3 APPENDIX A SUMMARY TEST PIT LOGS MOISTURE CONTENT 2-inch OD Split Spoon, SPT (140-lb. hammer, 30" drop) 3.25-inch OD Spilt Spoon (300-lb hammer, 30" drop) Non-standard penetration test (see boring log for details) Thin wall (Shelby) tube Grab Rock core Vane Shear Dusty, dry to the touch Damp but no visible water Visible free water Terms and Symbols for Boring and Test Pit Logs Density SILT / CLAY GRAVEL (<5% fines) GRAVEL (>12% fines) SAND (<5% fines) SAND (>12% fines) Liquid Limit < 50 Liquid Limit > 50 Breaks along defined planes Fracture planes that are polished or glossy Angular soil lumps that resist breakdown Soil that is broken and mixed Less than one per foot More than one per foot Angle between bedding plane and a planenormal to core axis Very Loose Loose Med. Dense Dense Very Dense SPTN-values Approx. Undrained ShearStrength (psf) <4 4 to 10 10 to 30 30 to 50 >50 <2 2 to 4 4 to 8 8 to 15 15 to 30 >30 SPTN-values Units of material distinguished by color and/orcomposition from material units above and below Layers of soil typically 0.05 to 1mm thick, max. 1 cm Layer of soil that pinches out laterally Alternating layers of differing soil material Erratic, discontinuous deposit of limited extent Soil with uniform color and composition throughout Approx. RelativeDensity (%) Gravel Layered: Laminated: Lens: Interlayered: Pocket: Homogeneous: Highly Organic Soils #4 to #10 sieve (4.5 to 2.0 mm) #10 to #40 sieve (2.0 to 0.42 mm) #40 to #200 sieve (0.42 to 0.074 mm) 0.074 to 0.002 mm <0.002 mm UNIFIED SOIL CLASSIFICATION SYSTEM MAJOR DIVISIONS GROUP DESCRIPTIONS Notes: MONITORING WELL <15 15 - 35 35 - 65 65 - 85 85 - 100 GW GP GM GC SW SP SM SC ML CL OL MH CH OH PT TEST SYMBOLS 50%or more passing #200 sieve Groundwater Level at time of drilling (ATD)Static Groundwater Level Cement / Concrete Seal Bentonite grout / seal Silica sand backfill Slotted tip Slough <250 250 - 500 500 - 1000 1000 - 2000 2000 - 4000 >4000 RELATIVE DENSITY / CONSISTENCY Fissured: Slickensided: Blocky: Disrupted: Scattered: Numerous: BCN: COMPONENT DEFINITIONS Dry Moist Wet 1. Soil exploration logs contain material descriptions based on visual observation and field tests using a systemmodified from the Uniform Soil Classification System (USCS). Where necessary laboratory tests have beenconducted (as noted in the "Other Tests" column), unit descriptions may include a classification. Please refer to thediscussions in the report text for a more complete description of the subsurface conditions. 2. The graphic symbols given above are not inclusive of all symbols that may appear on the borehole logs.Other symbols may be used where field observations indicated mixed soil constituents or dual constituent materials. COMPONENT SIZE / SIEVE RANGE COMPONENT SIZE / SIEVE RANGE SYMBOLS Sample/In Situ test types and intervals Silt and Clay Consistency SAND / GRAVEL Very Soft Soft Med. Stiff Stiff Very Stiff Hard Phone: 206.262.0370 Bottom of BoringBoulder: Cobbles: Gravel Coarse Gravel: Fine Gravel: Sand Coarse Sand: Medium Sand: Fine Sand: Silt Clay > 12 inches 3 to 12 inches 3 to 3/4 inches 3/4 inches to #4 sieve Atterberg Limit Test Compaction Tests Consolidation Dry Density Direct Shear Fines Content Grain Size Permeability Pocket Penetrometer R-value Specific Gravity Torvane Triaxial Compression Unconfined Compression Sand 50% or more of the coarsefraction passing the #4 sieve.Use dual symbols (eg. SP-SM)for 5% to 12% fines. for In Situ and Laboratory Testslisted in "Other Tests" column. 50% or more of the coarsefraction retained on the #4sieve. Use dual symbols (eg.GP-GM) for 5% to 12% fines. DESCRIPTIONS OF SOIL STRUCTURES Well-graded GRAVEL Poorly-graded GRAVEL Silty GRAVEL Clayey GRAVEL Well-graded SAND Poorly-graded SAND Silty SAND Clayey SAND SILT Lean CLAY Organic SILT or CLAY Elastic SILT Fat CLAY Organic SILT or CLAY PEAT ATT Comp Con DD DS %F GS Perm PP R SG TV TXC UCC Figure $LOG KEY 13-104_LOGS.GPJ PANGEO.GDT 6/18/13APPENDIX A Figure A-2 Test Pit No. TP-1 Approximate ground surface elevation: 86 Approximate location (WGS84): 47.52104, -122.20683 Depth (ft) USCS Material Description 0 – 2 SM/ML Grass and sod over medium dense, dark brown, slightly organic silty fine SAND/sandy SILT with trace gravel (SM/ML); dry to moist; poorly graded, roots [Topsoil] 2 – 4 SP-SM Dense, light grey-brown to orange-brown, slightly silty, gravelly fine SAND (SP-SM); dry to moist; poorly graded, iron-oxide staining [Weathered Till] 4 – 6 SM Very dense, olive brown, silty, gravelly fine SAND (SM); moist; poorly graded, cemented, cobbles up to one foot in diameter [Glacial Till] Plate 1 at right shows TP-1 at approximately 6-feet in depth TP-1 was terminated approximately 6 feet below ground surface. Groundwater seepage was not observed. APPENDIX A Figure A-3 Test Pit No. TP-2 Approximate ground surface elevation: 84 Approximate location (WGS84): 47.52124, -122.20690 Depth (ft) USCS Material Description 0 – ½ SM Grass and sod over medium dense, brown, silty fine SAND with trace gravel (SM); dry to moist; poorly graded, roots [Topsoil] ½ – 2 SM Dense, light grey-brown, silty, gravelly fine SAND (SM); dry to moist; poorly graded, trace iron-oxide staining, weakly cemented [Weathered Till] 2 – 5½ SM Very dense, olive brown to mottled red-brown, silty, gravelly fine SAND (SM); moist; poorly graded, cemented, cobbles up to six inches in diameter [Glacial Till] Plate 2 at right shows TP-2 at approximately 5½ feet in depth. TP-2 was terminated approximately 5½ feet below ground surface. Groundwater seepage was not observed. APPENDIX A Figure A-4 Date of Test Pit excavations: August 10, 2016 Test Pits Logged by: B. Weitering Test Pit No. TP-3 Approximate ground surface elevation: 84 Approximate location (WGS84): 47.52128, -122.20670 Depth (ft) USCS Material Description 0 – 1 SM/ML Grass and sod over medium dense, dark brown, slightly organic silty fine SAND/sandy SILT with trace gravel (SM/ML); dry to moist; poorly graded, roots [Topsoil] 1 – 3½ SM Dense, light grey-brown, silty, gravelly fine SAND (SM); dry to moist; poorly graded, trace iron-oxide staining, weakly to moderately cemented [Weathered Till] 3½ – 5 SP-SM Dense, grey-brown to red-brown, slightly silty, fine SAND with trace gravel (SP-SM); moist; poorly graded, iron-oxide staining [Glacial Till] Plate 3 at right shows TP-3 at Approximately 5 feet in depth. TP-3 was terminated approximately 5 feet below ground surface. Groundwater seepage was not observed. APPENDIX A APPENDIX B PREVIOUS SUBSURFACE EXPLORATIONS Project No.Figure No.16-204 B-1 16-153 Fig 2 Site Exploration Plan.grf 8/24/16 (13:47) NER Proposed Short-Plat and Development 3302 Burnett Avenue N Renton, Washington LEGEND: PREVIOUS BORING LOCATIONS Carleton Ave SouthApprox. Scale 1" = 300' Parcel A 84 80 Property L i n e (Elevation) 84 16th Avenue S Proposed 3-Story Rowhouse Proposed 3-Story Townhouses 90 82 78 Parcel B 82 Existing Residential Buildings to be Removed 84 86 AlleyTP-1 IT-1 TP-1 TP-2TP-3 TP-4 B-2A B-2B B-3 B-4 N Project Site B-24 B-23 B-10 Approximate Location of Previous Test Borings (Robertson & Roberts, 1961) Reference: King County iMap Proposed Short-Plat and Development 3302 Burnett Avenue NRenton, Washington Cross Section with Logs of Previous Test Borings B-10, B-23, and B-24 16-204 Figure B-216-204file.grf w/ file.dat 8/24/16 (14:21) TEA2Project No.Figure No. Legend: Approximate Location of Subject Property along Cross-Section Note: Figure modified from Cross Section by Robertson & Roberts dated October 30, 1961 ________________________________________________ 3213 Eastlake Ave E Ste B Seattle, WA 98102 T. (206) 262-0370 F. (206) 262-0374 Geotechnical & Earthquake Engineering Consultants July 31, 2020 File No. 16-204.200 Mr. Glen Merkel Avalon Project Inc. 15731 NE 8th St, POB 7447 Bellevue, WA 98008 Subject: Geotechnical Options Permeable Pavement 3302 Burnett Avenue North, Renton, Washington Dear Mr. Merkel, This letter is prepared to present our opinions regarding the feasibility of permeable pavement at the site. PanGEO excavated three (3) test pits during our field exploration in 2016. In general, the soils encountered at the test pit locations consisted of about 2 feet of silty sand with gravel (topsoil/fill and weathered till) overlying very dense and cemented glacial till (hardpan). Based on the soil conditions encountered in the test pits, it is our opinion that infiltration using drywells and infiltration trench is not feasible due to the shallow depth of the very dense glacial till (hardpan) encountered. However, in our opinion, the site soils are considered feasible to support low volume dispersion from the proposed permeable pavement, provided no additional collected stormwater from other areas (i.e. roof areas) is discharged onto the permeable pavement areas. Based on our experience with similar soils, it is also our opinion that the upper 2 feet of the site soils will provide a field infiltration rate of 0.3 in/hr or more. We appreciate the opportunity to be of service to you on this project. Please feel free to contact our office with any questions. Geotechnical Options for Permeable Pavement 3302 Burnett Avenue N, Renton, WA July 31, 2020 16-204 3302 Burnett Ave N Infiltration Ltr PanGEO, Inc. 2 Sincerely, 7/31/2020 H. Michael Xue, P.E. Principal Geotechnical Engineer