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EX_06_RS_TIR_210910_v2
Exhibit 6 RECEIVED 01/04/2022 JDing PLANNING DIVISION DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 TABLE OF CONTENTS PAGE PROJECT N ARRATIVE 1 CONDITIONS AND REQUIREMENTS SUMMARY OFF-SITE ANALYSIS FLOW C ONTROL A ND WATER QUALITY ANALYSIS AND D ESIGN CONVEYANCE SYSTEM ANALYSIS AND DESIGN SPECIAL REPORTS AND STUDIES OTHER PERMITS ESC ANALYSIS AND DESIGN BOND QUANTITIES, SUMMARIES, AND DECLARATION OF C OVENANT OPERATION AND MAINTENANCE MANUAL 2 5 5 8 8 8 8 8 8 TABLE OF APPENDICES A PPENDIX SOIL INFORMATION A SITE PLAN B TESC PLAN C OPERATION AND MAINTENANCE MANUAL D DOWNSTREAM A NALYSIS E WWHM F DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 1 SINGH 6TH ST SHORT PLAT TECHNICAL INFORMATION REPORT 1.0 - PROJECT OVERVIEW This report accompanies the drainage review plan prepared for the Singh 6th Street Short Plat project on parcel 1023059170 in Renton , Washington. The project has been designed to meet the requirements of the City’s 2017 Surface Water Design Manual (SWDM). FIGURE 1 – Vicinity Map The existing 0.46-acre site is a developed single -family residential lot . The neighboring parcels are also developed single-family residential lots. The parcel is a corner lot which has frontage on Northeast 6 th Street along the south property line and frontage on Nile Avenue Northeast along the east property line. The project will consist of dividing the lot into two single -family residential lots, the construction of a new single-family residence and driveway providing access to Northeast 6 th Street and frontage improvements along Nile Avenue Northeast . Stormwater runoff from the new residence will be dispersed on -site. The stormwater Project Site DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 2 from the frontage improvements will be conveyed to the City’s existing stormwater infrastructure. Predeveloped land cover characteristics are provided below in Table 1. TABLE 1. PREDEVELOPED AREAS Description Area (ft2) Total (ft2) Pervious Forest 14,377 14,377 Total 14,377 The soils present on the project site are identified in the NRCS soil survey as, Alderwood gravelly sandy loam (AgC) with shallow groundwater at about 18 to 37 inches below ground. TABLE 2. D EVELOPED AREAS Description Area (ft2) Total (ft2) Impervious New ADU roof a rea (Lot 1) 973 1,837 New driveway (Lot 1) 864 New Residence roof area (Lot 2) 3,411 3,514 New driveway (Lot 2) 103 Frontage Improvements (off-site by-pass) 2,651 2,651 Pervious Landscaping 9,488 9,488 Total 14,377 2.0 CONDITIONS AND REQUIREMENTS SUMMARY Under pre-developed conditions this property contains an existing residence, driveway, landscaping, and detached garage which will remain on proposed Lot 1 . The new Lot 2 is predominantly grassed. Along the south property line is a retaining wall to maintain the elevation of the City’s right -of-way improvements. The general slope of the land is towards the west based on topographic information per Renton’s GIS. On-site soils are identified in the N RCS Soil Survey as primarily Alderwood gravelly, sandy loam (type C soil). A copy of the NRCS soil survey map is provided in Appendix A . The project will result in 8,002 square feet of total impervious surface added and has more than 7,000 square feet of disturbed area . Because this project does not qualify for Simplified D rainage Review and is not subject to Large Project Drainage Review (more than 50 acres of project area), Directed Drainage Review will be required for this project. This report will show how the project complies with Core Requirements 1 through 9 and Special Requirements 1 through 5 , as follows: DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 3 Core Requirement #1: Discharge at Natural Location Under existing conditions, the majority of the stormwater runoff from the project site is naturally dispersed toward the south edge of the property. This project proposes to disperse part of the runoff from the existing and new roofs using infiltration trenches, splashblocks and dispersion trenches. The runoff from the new driveway on Lot 1 will disperse to the northwest with a sheet flow basic dispersion system. The remaining imperv ious area will sheet flow to the south. Core Requirement #2: Off-site Analysis The off-site system analysis is included in Section 3 .0 of this report. Core Requirement #3: Flow Control A WWHM analysis of the historic and developed surfaces has been completed and included with this report. This analysis shows that the 15 -minute, 100 -year peak flow rate under historic conditions from the area that will be disturbed by this project will not be surpassed by the 15-minute, 100-year peak flow rate under developed conditions by more than 0.15 cfs. This project is, theref ore, exempt from providing flow control facilities. Core Requirement #4: Conveyance System The conveyance system for this project consists of 6 -inch diameter PVC pipes that convey the stormwater to dispersion trenches. They are sized appropriately to han dle the stormwater that is anticipated. Core Requirement #5: Erosion and Sediment Control Erosion and sediment control requirements will be met for this project as described in Section 4.0. Core Requirement #6: Maintenance and Operations The on-site st ormwater features will be maintained privately by the property owner. Operations and Maintenance provisions are addressed in Appendix D . Core Requirement #7: Financial Guarantees and Liability Financial guarantees are not anticipated to be required for this single-family project. DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 4 Core Requirement #8: Water Quality The project is exempt from the requirement to provide basic water quality treatment since less than 5,000 square feet of new or replaced pollution -generating impervious surface (PGIS) is proposed that will not be fully dispersed. Core Requirement #9 : Flow Control BMPs This project will be constructed on a lot that is less than 22,000 square feet, therefore, be subject to Small Lot BMP Requirements, as discussed in Section 1.2.9.2.3 of the SWDM. This project will implement the BMPs found in the list in Section 1.2.9.2.3. Special Requirement #1: Other Adopted Area -Specific Requirements There are no known a rea -specific special requirements that apply to this project site. Special Requirement #2: Floodplain/Floodway Analysis There are no known flood hazard areas on or adjacent to this project. Special Requirement #3: Flood Protection Facilities Flood protection facility special requirements do not apply to this project. The project does not propose to construct a new or modify an existing flood protection facility. Special Requirement #4: Source Controls Since the proposed project is a single-family residence, source control measures are not anticipated to be required in conjunction with this projec t. There is no significant proposed outside-use or storage of pollutants. Special Requirement #5: Oil Control The proposed project does not require oil control measure s. The site is not considered high-use since it is a single-family residential project. DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 5 3.0 O FF-SITE ANALYSIS Downstream Basin: A Level 1 downstream analysis was completed for this project in July 2020. A Level 1 downstream analysis was completed using information from King County GIS information. The highest point of the developed site is at an elevation of about 500 feet at the northeast corner of the property. The site gently slopes from there to the southwest. Some of the runoff continues to flow in a south westerly direction to the public stormwater ditch located to the south of the property and some of the runoff passes through the neighboring lot (Parcel No. 7708200060) to the west of the property. The runoff from the property converges at and enters the public storm drain system in NE 6 th Street at the corner of the intersection of NE 6th Street and 147 th Avenue SE. The runoff then flows west through the public storm system to a public detention pond southwest of the property. The pond discharges north to Honey Creek and continues to flow north in the creek until it reaches a point 0.25 mile from the project site. An off-site a nalysis map is included in Appendix E. From a review of the information available relating to the downstream system . There were no recent existing drainage problems included in the C ity’s complaint database and no significant problems are anticipated as a result of the improvements proposed as part of this project. Upstream Tributary Basin: There are no known concentrated sources of stormwater discharge to this property. 4.0 FLOW CONTROL AND WATER Q UALITY FACILITY ANALYSIS AND D ESIGN Flow Control A WWHM analysis of the historic and developed surfaces has been completed and included with this report. This analysis shows that the 15 -minute, 100 -year peak flow rate under historic conditions (forest on type C soils) from the area that will be disturbed by this project will not be surpassed by the 100 -year peak flow rate under developed conditions by more than 0.15 cfs. This project is, therefore, exempt from providing flow control facilities. Analysis credits from Table 1.2.9 .A of the SWDM were applied to the analysis. Under developed conditions, the portion of the property that will be disturbed for construction will be covered by 973 square feet (0.023 acres) of ADU roof and 864 square feet (0.002 acres) of addition driveway on Lot 1. On Lot 2, the portion of the DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 6 property that will be disturbed for construction will be covered by 3,411 square feet (0.078 acres) of new roof and 103 square feet (0.0 16 acres) of new driveway. The runoff from 2 ,333 square feet (0.0 54 acres) of the new roof will be mitigated by the 9 0 cubic foot of gravel, 700 square feet (0.0 16 acres) of the new roof will be mitigated by the splashblocks, and 700 square feet (0.016 acres) of roof area will be mitigated by 10 - foot long basic dispersion trenches on Lot 2. The runoff from 700 square feet (0.0 16 acres) of roof area will be mitigated by splashblocks, and the new driveway will be mitigated with basic dispersion by sheet flow with a 2 -foot-wide gravel trench along the northwest side of the driveway in Lot 1. The impervious area mitigated by full infiltration, basic dispersion trenches, sheet flow , and the splashblocks will be modeled as 10% gr ass and 90% impervious in the WWHM model as allowed in Table 1.2.9.A of the SWDM. Total Modeled as Impervious Lawn Pasture Removed Roof 0.101 acres 0.037 acres 0.0 10 acres 0.000 acres 0.054 acres New Driveway 0.036 acres 0.03 5 acres 0.001 acres 0.000 acres 0.000 acres Sidewalk 0.047 acres 0.047 acres 0.000 acres 0.000 acres 0.000 acres Landscaping 0.146 acres 0.000 acres 0.146 acres 0.000 acres 0.000 acres Totals 0.330 acres 0.119 acres 0.157 acres 0.000 acres 0.054 acres Th e WWHM model for developed conditions produced a 15-minute, 100 -year peak flow of 0.181 cfs. This is less than a 0.15 cfs increase over the predeveloped 15-minute, 100-year peak of 0.0 61 cfs. This project is, therefore, exempt from providing additional flow control facilities. Detailed WWHM results are included in Appendix F. BMPs Section C.1.3.1 of the SWDM applies to projects on lots smaller than 22,000 square feet. Section C.1.3.1 state that, if the proposed project is on a site/lot smaller than 22,000 square feet, then flow control BMPs must be applied as specified in Appendix C, Section C.1.3.1 or the project must comply with the LID performance standard. This project proposes to apply small lot BMPs to the greatest extent feasible. Mitigation of new/replaced impervious surface: This project is required to apply BMPs from the Small Lot BMP Requirements in Section C.1.3.1 of Appendix C of the SWDM. The feasibility of each of those BMPs, in the order of preference required by the manual, is discussed below. Full Dispersion: It is infeasible to implement full dispersion BMP as detailed in Appendix C, Section C.2.1.1 because the native vegetative flow path for full dispersion is required to be at least 100 feet in length, which is not available on the project site. DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 7 Full Infiltration: Full infiltration BMPs is feasible, based on information received from Innovative Geo-Services, LLC dated April 16, 2021 , the characteristics of the soils on -site is medium sand. For each 1,000 square feet of the roof area requires 9 0 cubic foot gravel filled trenches as required by in Appendix C, Section C.2.2.4. There will be a 210 cubic foot of gravel of about 140 square feet basal area and 1.5 feet deep will be installed on the northwest corner of Lot 2 to mitigate total 2,333 square feet of the roof. There is not enough space for full infiltration facilities to mitigate the remaining new impervious area. Limited Infiltration: For the reason discussed in the above section , there is not enough space on site to mitigate the remaining new impervious areas. Therefore, limited infiltration is infeasible and not required to be considered for this project. Bioretention: For the reason discussed in the above section, there is not enough space on site to mitigate the remaining new impervious areas. Therefore, limited infiltration is infeasible and not required to be considered for this project. Permeable Pavement: It is infeasible to implement permeable pavement BMP as detailed in Appendix C, Section C.2.7.1 because the slope of the new driveway ranges from 6.5% to 12.5% on Lot 1, and the driveway on Lot 2 has a slope more than 15%. Therefore, permeable pavement is not feasible for this site. Basic Dispersion: Basic dispersion, as detailed in Appendix C, Section C.2.4, will be applied by allowing the driveway on Lot 1 to sheet flow to the west across the proposed vegetation. There will be two splashblocks that have 50 feet of vegetated flowpath downslope of them to mitigate the runoff from a portion of the existing roof and the new ADU’s roof. For Lot 2, there will be one splashblock that ha s 50 feet of vegetated flowpath downslope of them to mitigate the runoff from the roof of the new residence. There is not enough space to mitigate the runoff from the new 30-foot-long driveway. It would require a minimum 25 -foot setback from the property line to apply sheet flow basic dispersion. On Lot 1, the total new and replaced impervious area will be 1,837 square feet. On Lot 2, 3,514 square feet of new impervious areas are proposed. 3,033 square feet of the Lot 2 impervious areas will be mitigated. A total of 4,805 square feet of impervious areas will be mitigated. The minimum required area to be mitigated by BMP s is 20% of the total lot area. The total property area is approximately 18,812 square feet, therefore, the minimum area to be mitigated for this project is 3,762 square feet. 4,8 05 square feet will be mitigated and this satisfies the requirements of the SWDM. The remaining impervious area is located in ROW and cannot be mitigated. The runoff that will not be mitigated from the site and the frontage improvements will sheet flow towards the existing ditch along the NE 6 th Street. DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 8 Mitigation of Water Quality Impacts: Mitigation will not be required because the project will create less than 5,000 square feet of new pollution -generating impervious surface. 5.0 CONVEYANCE SYSTEM ANALYSIS AND DESIGN Conveyance pipes for this project consist of a typical downspout connection that will connect the roof runoff to the drywell in front of the proposed house. 6 -inch PVC pipe at a minimum slope of 1% will adequately convey all of the runoff from the roof to the catch basin in front of the proposed house. 6.0 SPECIAL REPORTS AND STUDIES A geotechnical report will be provided under a separate cover . 7.0 OTHER PERMITS A building permit for the proposed home and ADU will be required for this project. 8.0 ESC ANALYSIS AND DESIGN Erosion and sediment control requirements will include the delineation of clearing limits via flagging, proper cover measures for the protection of disturbed areas, perimeter protection with silt fencing on an as-needed basis, and a stabilized construction entrance per City of Renton standards. The Erosion and Sediment Control Plan has been included as part of the construction pla ns and is included in Appendix C . 9.0 BOND QUANTITIES, FACILITY SUMM ARIES, AND DECLARATION OF COVENANT A bond quantities worksheet is not expected to be required by the City of Renton. 10.0 OPERATIONS AND MAINTENANCE MANUAL The stormwater BMPs proposed for this project will be maintained privately by the property owner. The operations and maintenance details for this private facility are provided in the Operations and Maintenance Manual found in Appendix D DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 APPENDIX A: SOIL INFORMATION DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 INNOVATIVE GEO-SERVICES, LLC ENGINEERING GEOLOGY SERVICES ENGGEOLOGIST.COM 17903 82nd ST E, Bonney Lake, WA 98391 253 279-4205 c rex@enggeologist.com HS Construction and Investments, LLC April 29, 2021 5140 S 172nd Lane Seatac, Washington 98188 Attn: Raman Sidhu Singh 6th ST Short Plat Geotechnical Evaluation Address: 615 Nile AV NE Renton, WA Parcel No. 1023059026 Site Visit 4/16/2021 INTRODUCTION It is the intent of this evaluation to describe the surface and subsurface conditions on the nearly 0.44-acre residential parcel (approx. 19,351 sf) located on the west side of Nile AV NE and north of NE 6th ST in Renton, WA. Development plans call for creating 1 new single family residential lot with access from NE 6th Street near the southeast corner of the new lot. The parent parcel is rectangular shaped and is approximately 200 ft long (E/W) and approximately 100 ft. (N/S) wide. The parent parcel will be divided into 2 residential lots which will be 0.24 to 0.20 acres in size with an existing residential structure on the parent lot. The property has a gentle 11% grade to the southwest. Topographically the parcel has 25 ft. of elevation change over 225 ft. The surface is covered with lawn grasses and some berry vines. No geologic or erosion hazards occur on the property as defined by the City of Renton, Chapter 4-3-050, Critical Areas Regulations. Development plans are to create 2 single-family home on the 0.44-acre property. The new homes will utilize a municipal water and sewer, and an on-site storm water control system. The new lot will be situated west of the existing home. This evaluation is for the exclusive use of HS Construction and Investments, LLC, their consultants and contractors for the intended purpose described. Site observations and exploration methods applied and described in this evaluation are standard practices for the industry. Sources of information cited are generally accepted resources when utilized in conjunction with field reconnaissance as confirmation. Opinions are based on use of these standardized practices to adequately characterize the local surficial geology and general conditions at the site. An Engineering Geologist from Innovative GEO-Services, LLC (IGS) visited the site on April 16th, 2021 to observe site conditions, explore near surface soil textures and conditions relating to the development of the residential lots which will be accessed from Nile AV NE to the eastern lot and from NE 6th ST. for the western lot. Preliminary site plans and topography were provided by AP Consulting Engineers, PLLC. Additional information was obtained from the King County GIS system. DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh 6th Street Short Plat Geotechnical Evaluation April 29, 2021 Page 2 17903 82nd ST E, Bonney Lake, WA 98391 253 279-4205 c rex@enggeologist.com SITE AND PROJECT DESCRIPTION The residential parcel is a nearly rectangular shaped property with two distinct topographic areas. The eastern portion of land is level to gently sloping to the west while the western lot slopes to the southwest with gentle grades. The eastern parcel contains a single-family residential structure which is currently being remodeled. The western lot is undeveloped. Access to the property is from SE 270th ST near the northeast corner of the parcel. Development plans show the new home will be situated in the north third of the parcel where the surface is nearly level. The proposed development is surrounded by similar residential development and access. The surrounding homes are typically wood framed structures which utilize conventional foundation systems. SINGH 6TH STREET PLAT SITE PLAN EXPLORATION MAP Site Plan Provided by AP Consulting Engineers, PLLC (nts) IGS SOIL PITS (4/16/2021) SP 3 SP 4 EXISTING HOUSE 11% DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh 6th Street Short Plat Geotechnical Evaluation April 29, 2021 Page 3 17903 82nd ST E, Bonney Lake, WA 98391 253 279-4205 c rex@enggeologist.com SITE SOILS The Natural Resource Conservation Service (NRCS) describe the soils across the parcel as Alderwood gravelly sandy loam (AgC). NRCS SOIL MAPPING DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh 6th Street Short Plat Geotechnical Evaluation April 29, 2021 Page 4 17903 82nd ST E, Bonney Lake, WA 98391 253 279-4205 c rex@enggeologist.com NRCS SOIL CLASSIFICATION Alderwood AgC – Alderwood gravelly sandy loam, 6 – 15 percent slopes The Alderwood gravelly sandy loam is moderately well drained. It formed in glacial till on broad uplands. It is extensive in the Lake Tapps area. Predominant native vegetation is made up of hardwoods and conifers. The typical elevation of this soil series ranges from 200 to 800 feet. In a typical soil profile, a mat of undecomposed needles and wood fragments rests upon a 1 ½ inch thick very dark grayish brown gravelly sandy loam surface layer. The subsoil and the upper part of the substratum, to a depth of 38 inches, are dark yellowish brown, brown, and dark grayish brown gravelly sandy loam. The lower portion of the substratum, to a depth of more than 60 inches, is weakly cemented compact glacial till. A seasonal water table is perched above the very slowly permeable, weakly cemented and compact part of the substratum during periods of heavy rainfall. However, the perched water table is of short duration because the water flows laterally above this layer to seeps at the bottom of slopes. Very few roots penetrate this dense substratum. The available water capacity is low. Surface runoff is medium, and the erosion hazard is moderate. This rolling Alderwood soil is moderately well drained. It formed in glacial till on broad uplands. It is extensive in the Lake Tapps area. Vegetation is hardwoods and conifers. Elevation ranges from 200 to 800 feet. The mean annual precipitation is about 35 inches, mean annual air temperature is about 50 degrees F, and the frost- free season averages about 180 days. Individual soil areas average about 125 acres in size. Most slopes average about 8 percent. Granite boulders and stones are strewn across some slopes. Included with this soil in mapping are small areas of better drained Indianola loamy sand on the side slopes and poorer drained Norma sandy loam or Dupont muck in troughs. In addition, some areas of Alderwood gravelly sandy loam and Kapowsin gravelly loam, zero to six percent slopes, are included. In a typical soil profile, a mat of undecomposed needles and wood fragments rests upon a 1 ½ inch thick very dark grayish brown gravelly sandy loam surface layer. The subsoil and the upper part of the substratum, to a depth of 38 inches, are dark yellowish brown, brown, and dark grayish brown gravelly sandy loam. The lower parrot of the substratum, to a depth of more than 60 inches, is weakly cemented compact glacial till. Reaction is medium acid. The water table is perched above the very slowly permeable, weakly cemented and compact part of the substratum during periods of heavy rainfall. However, the perched water table is of short duration because the water flows laterally above this layer to seeps at the bottom of slopes. Very few roots penetrate this dense substratum. The available water capacity is low. Surface runoff is medium, and the erosion hazard is moderate. Because of its proximity to urban centers, this Alderwood soil is subject to urbanization pressure. The soil has an inherent ability to support a large load. Soil slope and the weakly cemented, compact substratum are its limiting features. In areas of moderate to high population density, onsite sewage disposal systems often fail or do not function properly during periods of rainfall in winter. Excavation for basements and utility lines is difficult to cover excavated soil material. DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh 6th Street Short Plat Geotechnical Evaluation April 29, 2021 Page 5 17903 82nd ST E, Bonney Lake, WA 98391 253 279-4205 c rex@enggeologist.com SITE GEOLOGY According to maps from the Washington Division of Geology and Earth Resources, this region of King County lies in the glacial lowland area of multiple glacial advance and recessional periods. The surface deposits are described as Proglacial stratified drift deposits of gravelly sands, fine sands described as ground moraine deposits. Moraines may form through a number of processes, depending on the characteristics of sediment, the dynamics on the ice, and the location on the glacier in which the moraine is formed. Moraine forming processes may be loosely divided into passive and active. Passive processes involve the placing of chaotic supraglacial sediments onto the landscape with limited reworking, typically forming hummocky moraines. These moraines are composed of supraglacial sediments from the ice surface. Active processes form or rework moraine sediment directly by the movement of ice, known as glacio-tectonism. These forms push moraines and thrust-block moraines, which are often composed of till and reworked proglacial sediment. Moraine may also form by the accumulation of sand and gravel deposits from glacial streams emanating from the ice margin. These fan deposits may coalesce to form a long moraine bank marking the ice margin. Several processes may combine to form and rework a single moraine, and most moraines record a continuum of processes. Ground moraines are till-covered areas with irregular topography and no ridges, often forming gently rolling hills or plains. They are accumulated at the base of the ice as lodgment till, but may also be deposited as the glacier retreats. In alpine glaciers, ground moraines are often found between the two lateral moraines. Ground moraines may be modified into drumlins by the overriding ice. Geologic Map of King County (Excerpt) Compiled by Booth, Troost & Wisher, March 2007 Qvt SINGH 6TH ST PLAT DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh 6th Street Short Plat Geotechnical Evaluation April 29, 2021 Page 6 17903 82nd ST E, Bonney Lake, WA 98391 253 279-4205 c rex@enggeologist.com City of Renton Critical Area Regulations 4-3-050B APPLICABILITY: 1. Lands to Which These Regulations Apply and Non-regulated Lands: The following critical areas are regulated by this Section. Multiple development standards may apply to a site feature based upon overlapping critical area(s) and/or critical area classifications: a. Flood hazard areas. b. Steep slopes (must have a minimum vertical rise of fifteen feet (15')), landslide hazards, erosion hazards, seismic hazards, and/or coal mine hazards or on sites within fifty feet (50') of steep slopes, landslide hazards, erosion hazards, seismic haz ards, and/or coal mine hazards classified under RMC 4-3-050G5a which are located on abutting or adjacent sites. c. Habitat Conservation Areas. d. Streams and Lakes. All applicable requirements of this Section apply to Class F, Np, and Ns water bodies, as defined in subsection G7 of this Section or on sites within one hundred feet (100') of Class F, Np, and Ns water bodies, except Type S water bodies, inventoried as “Shorelines of the State,” are not subject to this Section, and are regulated in RMC 4-3-090, Shoreline Master Program Regulations, and RMC 4-9-190, Shoreline Permits. e. Wellhead Protection Areas. f. Wetlands, Categories I, II, III, and IV or on sites within two hundred feet (200') of Category I, II, III, and IV wetlands. Wetlands created or restored as a part of a mitigation project are regulated wetlands. Regulated wetlands do not include those artificial wetlands intentionally created from no wetland sites, including, but not limited to, irrigation and drainage ditches, grass-lined swales, canals, detention facilities, wastewater treatment facilities, farm ponds, and landscape amenities, or those wetlands created after July 1, 1990, that were unintentionally created as a result of the construction of a road, street, or h ighway. g. Sites Separated from Critical Areas, Nonregulated: As determined by the Administrator, these regulations may not apply to development proposed on sites that are separated from critical areas by pre-existing, intervening, and lawfully created structures, roads, or other substantial existing improvements. For the purposes of this Section, the intervening lots/parcels, roads, or other substantial improvements shall be found to: i. Separate the subject upland property from the critical area due to their height or width; and ii. Substantially prevent or impair delivery of most functions from the subject upland property to the critical area. Such determination and evidence shall be included in the application file. Public notification shall be given as follows: (a) For applications that are not subject to notices of application pursuant to Chapter 4 -8 RMC, notice of the buffer determination shall be given by posting the site and notifying parties of record, if any, in accordance with Chapter 4-8 RMC. (b) For applications that are subject to notices of application, the buffer determination or request for determination shall be included with notice of application. Upon determination, notification of parties of record, if any, shall be made. DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh 6th Street Short Plat Geotechnical Evaluation April 29, 2021 Page 7 17903 82nd ST E, Bonney Lake, WA 98391 253 279-4205 c rex@enggeologist.com Findings Based on our site observations, explorations and research it is our opinion there are no geologic hazards as defined by the City of Renton occur on or near the proposed development. The proposed new residential lots are proposed across gentle grades. The property is underlain by a massive deposit of glacial till. This glacial till dominates the regions and consists of a very dense, nearly impermeable compressed silty sand and gravel. The upland area and surface deposits are consistent with weathered glacial till. No steep slopes as defined by the City occur on or adjacent to the property. Our site observations and research found no indications of current or past morphology consistent with landslide activity. Site Preparation Preparation of the project site should involve erosion control, temporary drainage, clearing, stripping, cutting, filling, excavations, and subgrade compaction. Erosion Control: Before new construction begins, an appropriate erosion control system should be installed. This system should collect and filter all surface run off through either silt fencing or a series of properly placed and secured straw bales. We anticipate a system of berms and drainage ditches around construction areas will provide an adequate collection system. If silt fencing is selected as a filter, this fencing fabric should meet the requirements of WSDOT Standard Specification 9-33.2 Table 3. In addition, silt fencing should embed a minimum of 6 inches below existing grade. If straw baling is used as a filter, bales should be secured to the ground so that they will not shift under the weight of retained water. Regardless of the silt filter selected, an erosion control system requires occasional observation and maintenance. Specifically, holes in the filter and areas where the filter has shifted above ground surface should be replaced or repaired as soon as they are identified. Temporary Drainage: We recommend intercepting and diverting any potential sources of surface or near-surface water within the construction zones before stripping begins. Because the selection of an appropriate drainage system will depend on the water quantity, season, weather conditions, construction sequence, and contractor's methods, final decisions regarding drainage systems are best made in the field at the time of construction. Based on our current understanding of the construction plans, surface, and subsurface conditions, we anticipate that curbs, berms, or ditches placed around the work areas will adequately intercept surface water runoff. Clearing and Stripping: After surface and near-surface water sources have been controlled, the construction areas should be cleared and stripped of all duff and topsoil. Also, it should be realized that if the stripping operation proceeds during wet weather, a generally greater stripping depth might be necessary to remove disturbed moisture-sensitive soils; therefore, stripping is best performed during a period of dry weather. Site Excavations: Based on our explorations, we expect site excavation will encounter dense to very dense gravelly sand with cobbles. Special teeth on excavators or rippers on bulldozers may be needed to rapidly excavate these soils. Excavations over 4 ft in depth may require side wall support. Dewatering: Explorations did not observe groundwater at elevations where earth work activity will occur, nor do we expect that groundwater will be present in excavations for the planned development. However, DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh 6th Street Short Plat Geotechnical Evaluation April 29, 2021 Page 8 17903 82nd ST E, Bonney Lake, WA 98391 253 279-4205 c rex@enggeologist.com if groundwater is encountered, we anticipate that an internal system of ditches, sump holes, and pumps will be adequate to temporarily dewater excavations. Temporary Cut Slopes: All temporary soil slopes associated with site cutting or excavations should be adequately inclined to prevent sloughing and collapse. Temporary cut slopes in loose gravelly sand should be no steeper than 1½H:1V and should conform to WISHA regulations Subgrade Compaction: Exposed subgrades for footings and floors should be compacted to a firm, unyielding state before new concrete or fill soils are placed. Any localized zones of looser granular soils observed within a subgrade should be compacted to a density commensurate with the surrounding soils. In contrast, any organic, soft, or pumping soils observed within a subgrade should be over excavated and replaced with a suitable structural fill material. Site Filling: Our conclusions regarding the reuse of on-site soils and our comments regarding wet-weather filling are presented subsequently. Regardless of soil type, all fills should be placed and compacted according to our recommendations presented in the Structural Fill section of this report. Specifically, building pad fill soil should be compacted to a uniform density of at least 95 percent (based on ASTM:D - 1557). On-Site Soils: We offer the following evaluation of these on-site soils in relation to potential use as structural fill: • Surficial Organic Soils: The duff and topsoil mantling some of the sites are not suitable for use as structural fill under any circumstances, due to their high organic content. Consequently, these materials can be used only for non-structural purposes, such as in landscaping areas. • Weathered and Unweather Glacial Till: The weathered and weathered glacial till layers are sensitive to moisture content variations. These soils can be reused during dry conditions but will become increasingly difficult to reuse as conditions become wetter. Permanent Slopes: Permanent cut slopes and fill slopes are not anticipated or shown on current designs. If permanent cut or fill slopes are incorporated, they should be adequately inclined to minimize long-term raveling, sloughing, and erosion. We generally recommend no permanent slopes be steeper than 2H:1V. For all soil types, the use of flatter slopes (such as 2½H:1V) would further reduce long-term erosion and facilitate revegetation. Spread Footings In our opinion, conventional spread footings will provide adequate support for the residential structures if the subgrades are properly prepared. Footing Depths and Widths: For frost and erosion protection, the bases of all exterior footings should bear at least 18 inches below adjacent outside grades, whereas the bases of interior footings need bear only 12 inches below the surrounding slab surface level. To reduce post-construction settlements, continuous (wall) and isolated (column) footings should be at least 18 and 24 inches wide, respectively. DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh 6th Street Short Plat Geotechnical Evaluation April 29, 2021 Page 9 17903 82nd ST E, Bonney Lake, WA 98391 253 279-4205 c rex@enggeologist.com Bearing Subgrades: Footings should bear on medium dense or denser, undisturbed native soils which have been stripped of surficial organic soils, or on properly compacted structural fill which bears on undisturbed native soils which have been stripped of surficial organic soils. In general, before footing concrete is placed, any localized zones of loose soils exposed across the footing subgrades should be compacted to a firm, unyielding condition, and any localized zones of soft, organic, or debris-laden soils should be over excavated and replaced with suitable structural fill. Care should be taken in identifying pockets of loose fill, placed during prior grading activities, which may be scattered across the site. Subgrade Observation: All footing subgrades should consist of firm, unyielding, native soils or structural fill materials compacted to a density of at least 95 percent (based on ASTM:D-1557). Footings should never be cast atop loose, soft, or frozen soil, slough, debris, existing uncontrolled fill, or surfaces covered by standing water. Bearing Pressures: For static loading, footings which bear on properly prepared subgrades can be designed for a maximum allowable soil bearing pressure of 2,000 pounds per square foot (psf). A one- third increase in allowable soil bearing capacity may be used for short-term loads created by seismic or wind related activities. Footing Settlements: Assuming structural fill soils are compacted to a medium dense or denser state, we estimate that total post-construction settlements of properly designed footings bearing on properly prepared subgrades will not exceed 1 inch. Differential settlements for comparably loaded elements may approach one-half of the actual total settlement over horizontal distances of approximately 50 feet. Footing Backfill: To provide erosion protection and lateral load resistance, it is recommended all footing excavations be backfilled on both sides of the footings and stem walls after the concrete has cured. Either imported structural fill or non-organic on-site soils can be used for this purpose, contingent on suitable moisture content at the time of placement. Regardless of soil type, all footing backfill soil should be compacted to a density of at least 90 percent (based on ASTM:D-1557). Lateral Resistance: Footings that have been properly backfilled as recommended above will resist lateral movements by means of passive earth pressure and base friction. We recommend using an allowable passive earth pressure of 300 pcf in the glacial till onsite, 250 pcf in the glacial outwash onsite, and 160 pcf for the silt onsite. We recommend an allowable base friction coefficient of 0.35 for glacial till and outwash, and 0.20 for silt. Slab-On-Grade Floors Soil-supported slab-on-grade floors can be used in the proposed structures if the subgrades are properly prepared. We offer the following comments and recommendations concerning slab-on-grade floors. Floor Subbase: Structural fill subbases do not appear to be needed under soil-supported slab-on-grade floors at the site. However, the final decision regarding the need for subbases should be based on actual subgrade conditions observed at the time of construction. If a subbase is needed, all subbase fills should be compacted to a density of at least 95 percent (based on ASTM:D-1557). Capillary Break and Vapor Barrier: To retard the upward wicking of groundwater beneath the floor slab, we recommend that a capillary break be placed over the subgrade. Ideally, this capillary break wo uld consist of a 4-inch-thick layer of pea gravel or other clean, uniform, well-rounded gravel, such as “Gravel DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh 6th Street Short Plat Geotechnical Evaluation April 29, 2021 Page 10 17903 82nd ST E, Bonney Lake, WA 98391 253 279-4205 c rex@enggeologist.com Backfill for Drains” per WSDOT Standard Specification 9-03.12(4), but clean angular gravel can be used if it adequately prevents capillary wicking. In addition, a layer of plastic sheeting (such as Crosstuff, Visqueen, or Moistop) should be placed over the capillary break to serve as a vapor barrier. During subsequent casting of the concrete slab, the contractor should exercise care to avoid puncturing this vapor barrier. Drainage Systems In our opinion, the proposed new structures should be provided with permanent drainage systems to reduce the risk of future moisture problems. We offer the following recommendations and comments for drainage design and construction purposes. Perimeter Drains: Site soil characteristics observed indicate the use of footing drains is optional. Footing drains if utilized are a perimeter drain system to collect seepage water. This drain should consist of a 4- inch-diameter perforated pipe within an envelope of pea gravel or washed rock, extending at least 6 inches on all sides of the pipe, and the gravel envelope should be wrapped with filter fabric to reduce the migration of fines from the surrounding soils. Ideally, the drain invert would be installed no more than 8 inches above the base of the perimeter footings. Subfloor Drains: Based on the groundwater conditions observed in our site explorations, we do not infer a need for subfloor drains. Discharge Considerations: If possible, all storm water drains should discharge to an approved infiltration system or other suitable location by gravity flow. Check valves should be installed along any drainpipes that discharge to a sewer system, to prevent sewage backflow into the drain system. Runoff Water: Roof-runoff and surface-runoff water should not discharge into the perimeter drain system. Instead, these sources should discharge into separate tight line pipes and be routed away from the building to a storm drain or other appropriate location. Grading and Capping: Final site grades should slope downward away from the buildings so that runoff water will flow by gravity to suitable collection points, rather than ponding near the building. Ideally, the area surrounding the building would be capped with concrete, asphalt, or low-permeability (silty) soils to minimize or preclude surface-water infiltration. Infiltration Rates: Soil characteristics and grain size observed in two soil pits excavated across the parcel found the native soil to be a fine sand and silt with some gravel (weathered Glacial Till) transitioning to a very dense gray glacial till. Raw infiltration rates in the upper 36 to 48 inches of soil can anticipate 10 in/hr. or less in the Alderwood soil based on the observed soil and grain size. We recommend storm water control plans use surface dispersion to the north side of the new home. Soil infiltration logs are attached to this report. Structural Fill The term "structural fill" refers to any placed under foundations, retaining walls, slab-on-grade floors, sidewalks, pavements, and other structures. Our comments, conclusions, and recommendations concerning structural fill are presented in the following paragraphs. DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh 6th Street Short Plat Geotechnical Evaluation April 29, 2021 Page 11 17903 82nd ST E, Bonney Lake, WA 98391 253 279-4205 c rex@enggeologist.com Materials: Typical structural fill materials include clean sand, gravel, pea gravel, washed rock, crushed rock, well-graded mixtures of sand and gravel (commonly called "gravel borrow" or "pit-run"), and miscellaneous mixtures of silt, sand, and gravel. Recycled asphalt, concrete, and glass, which are derived from pulverizing the parent materials, are also potentially useful as structural fill in certain applications. Soils used for structural fill should not contain any organic matter or debris, nor any individual particles greater than about 6 inches in diameter. Fill Placement: Clean sand, gravel, crushed rock, soil mixtures, and recycled materials should be placed in horizontal lifts not exceeding 8 inches in loose thickness, and each lift should be thoroughly compacted with a mechanical compactor. Compaction Criteria: Using the Modified Proctor test (ASTM:D-1557) as a standard, we recommend that structural fill used for various on-site applications be compacted to the following minimum densities: Fill Application Minimum Compaction Footing subgrade and bearing pad Foundation backfills Slab-on-grade floor subgrade and subbase 95 percent 90 percent 95 percent Subgrade Observation and Compaction Testing: Regardless of material or location, all structural fills should be placed over firm, unyielding subgrades prepared in accordance with the Site Preparation section of this report. The condition of all subgrades should be observed by geotechnical personnel before filling or construction begins. Also, fill soil compaction should be verified by means of in-place density tests performed during fill placement so that adequacy of soil compaction efforts may be evaluated as earthwork progresses. Soil Moisture Considerations: The suitability of soils used for structural fill depends primarily on their grain-size distribution and moisture content when they are placed. As the "fines" content (that soil fraction passing the U.S. No. 200 Sieve) increases, soils become more sensitive to small changes in moisture content. Soils containing more than about 5 percent fines (by weight) cannot be consistently compacted to a firm, unyielding condition when the moisture content is more than 2 percentage points above or below optimum. For fill placement during wet-weather site work, we recommend using "clean" fill, which refers to soils that have a fines content of 5 percent or less (by weight) based on the soil fraction passing the U.S. No. 4 Sieve. RECOMMENDED ADDITIONAL SERVICES Because the future performance and integrity of the structural elements will depend largely on proper site preparation, drainage, fill placement, and construction procedures, monitoring and testing by experienced geotechnical personnel should be considered an integral part of the construction process. Consequently, we recommend that IGS be retained to provide the following post-report services: • Review all construction plans and specifications to verify that our design criteria presented in this report have been properly integrated into the design. • Prepare a letter summarizing all review comments (if required by the City of Renton). DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh 6th Street Short Plat Geotechnical Evaluation April 29, 2021 Page 12 17903 82nd ST E, Bonney Lake, WA 98391 253 279-4205 c rex@enggeologist.com • Check all completed subgrades for footings and slab-on-grade floors before concrete is poured, to verify their bearing capacity; and • Prepare a post-construction letter summarizing all field observations, inspections, and test results (if required). CLOSURE The conclusions and recommendations presented in this report are based, in part, on the explorations that we performed for this study; therefore, if variations in the subgrade conditions are observed at a later time, we may need to modify this report to reflect those changes. Also, because the future performance and integrity of the project elements depend largely on proper initial site preparation, drainage, and construction procedures, monitoring and testing by experienced geotechnical personnel should be considered an integral part of the construction process. IGS is available to provide geotechnical monitoring of soils throughout construction. Innovative GEO-Services, LLC Rex Humphrey, L.E.G. Engineering Geologist 04/30/2021 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh 6th Street Short Plat Geotechnical Evaluation April 29, 2021 Page 14 17903 82nd ST E, Bonney Lake, WA 98391 253 279-4205 c rex@enggeologist.com SOIL TEST PIT LOGS SOIL TEST PITS 1 THROUGH 4 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 494.5 493.0 492.0 491.5 CL- ML SP- SC SP- SM SP 0.5 2.0 3.0 3.5 (CL-ML) SOD TOPSOIL, ORGANIC, SANDY, SOME GRAVEL, DARK BROWN, DRY (SP-SC) SAND, GRAVELLY, BROWN, ROCKY, LOOSE TO MEDIUM DENSE, DRY (SP-SM) SAND, GRAVELLY, TAN, MEDIUM DENSE, DRY (SP) GLACIAL TILL, GRAY, SLIGHTLY MOTTLED, ROCKY, DRY Bottom of test pit at 3.5 feet. NOTES GROUND ELEVATION 495 ft msl LOGGED BY RBH EXCAVATION METHOD MiniExcavator TEST PIT SIZE 2' X 4' EXCAVATION CONTRACTOR Owner GROUND WATER LEVELS: CHECKED BY RBH DATE STARTED 4/16/21 COMPLETED 4/16/21 AT TIME OF EXCAVATION --- AT END OF EXCAVATION --- AFTER EXCAVATION ---DEPTH(ft)0 1 2 3 SAMPLE TYPENUMBERPAGE 1 OF 1 SOIL PIT NUMBER TP 1 PROJECT NAME Singh 6th Street Short Plat PROJECT LOCATION 56XX NE 6th Street, Renton CLIENT Raman Sidhu PROJECT NUMBER 042113 GENERAL BH / TP / WELL - GINT STD US.GDT - 4/29/21 14:17 - F:\2021 PROJECTS\032112 SIDHU PLAT GEO\DATA\SIGNH 6TH STREET SHORT PLAT SOIL PITS.GPJINNOVATIVE GEO-SERVICES, LLC Engineering Geology and Septic Design 253 279-4205 rex@enggeologist.com U.S.C.S.MATERIAL DESCRIPTION GRAPHICLOGDocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 489.0 488.5 487.5 487.0 CL- ML SP- SC SP- SM SP 1.0 1.5 2.5 3.0 (CL-ML) SOD TOPSOIL, ORGANIC, SANDY, SOME GRAVEL, DARK BROWN, DRY (SP-SC) SAND, GRAVELLY, BROWN, ROCKY, LOOSE TO MEDIUM DENSE, DRY (SP-SM) SAND, GRAVELLY, TAN, MEDIUM DENSE, DRY (SP) GLACIAL TILL, GRAY, SLIGHTLY MOTTLED, ROCKY, DRY Bottom of test pit at 3.0 feet. NOTES GROUND ELEVATION 490 ft msl LOGGED BY RBH EXCAVATION METHOD MiniExcavator TEST PIT SIZE 2' X 4' EXCAVATION CONTRACTOR Owner GROUND WATER LEVELS: CHECKED BY RBH DATE STARTED 4/16/21 COMPLETED 4/16/21 AT TIME OF EXCAVATION --- AT END OF EXCAVATION --- AFTER EXCAVATION ---DEPTH(ft)0 1 2 3 SAMPLE TYPENUMBERPAGE 1 OF 1 SOIL PIT NUMBER TP 2 PROJECT NAME Singh 6th Street Short Plat PROJECT LOCATION 56XX NE 6th Street, Renton CLIENT Raman Sidhu PROJECT NUMBER 042113 GENERAL BH / TP / WELL - GINT STD US.GDT - 4/29/21 14:17 - F:\2021 PROJECTS\032112 SIDHU PLAT GEO\DATA\SIGNH 6TH STREET SHORT PLAT SOIL PITS.GPJINNOVATIVE GEO-SERVICES, LLC Engineering Geology and Septic Design 253 279-4205 rex@enggeologist.com U.S.C.S.MATERIAL DESCRIPTION GRAPHICLOGDocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 484.5 483.0 482.5 482.0 CL- ML SP- SC SP- SM SP 0.5 2.0 2.5 3.0 (CL-ML) SOD TOPSOIL, ORGANIC, SANDY, SOME GRAVEL, DARK BROWN, DRY (SP-SC) SAND, GRAVELLY, BROWN, ROCKY, LOOSE TO MEDIUM DENSE, DRY (SP-SM) SAND, GRAVELLY, TAN, MEDIUM DENSE, DRY (SP) GLACIAL TILL, GRAY, SLIGHTLY MOTTLED, ROCKY, DRY Bottom of test pit at 3.0 feet. NOTES GROUND ELEVATION 485 ft msl LOGGED BY RBH EXCAVATION METHOD MiniExcavator TEST PIT SIZE 2' X 4' EXCAVATION CONTRACTOR Owner GROUND WATER LEVELS: CHECKED BY RBH DATE STARTED 4/16/21 COMPLETED 4/16/21 AT TIME OF EXCAVATION --- AT END OF EXCAVATION --- AFTER EXCAVATION ---DEPTH(ft)0 1 2 3 SAMPLE TYPENUMBERPAGE 1 OF 1 SOIL PIT NUMBER TP 3 PROJECT NAME Singh 6th Street Short Plat PROJECT LOCATION 56XX NE 6th Street, Renton CLIENT Raman Sidhu PROJECT NUMBER 042113 GENERAL BH / TP / WELL - GINT STD US.GDT - 4/29/21 14:17 - F:\2021 PROJECTS\032112 SIDHU PLAT GEO\DATA\SIGNH 6TH STREET SHORT PLAT SOIL PITS.GPJINNOVATIVE GEO-SERVICES, LLC Engineering Geology and Septic Design 253 279-4205 rex@enggeologist.com U.S.C.S.MATERIAL DESCRIPTION GRAPHICLOGDocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 484.5 482.5 482.0 481.5 CL- ML SP- SC SP- SM SP 0.5 2.5 3.0 3.5 (CL-ML) SOD TOPSOIL, ORGANIC, SANDY, SOME GRAVEL, DARK BROWN, DRY (SP-SC) SAND, GRAVELLY, BROWN, ROCKY, LOOSE TO MEDIUM DENSE, DRY (SP-SM) SAND, GRAVELLY, TAN, MEDIUM DENSE, DRY (SP) GLACIAL TILL, GRAY, SLIGHTLY MOTTLED, ROCKY, DRY Bottom of test pit at 4.0 feet. NOTES GROUND ELEVATION 485 ft msl LOGGED BY RBH EXCAVATION METHOD MiniExcavator TEST PIT SIZE 2' X 4' EXCAVATION CONTRACTOR Owner GROUND WATER LEVELS: CHECKED BY RBH DATE STARTED 4/16/21 COMPLETED 4/16/21 AT TIME OF EXCAVATION --- AT END OF EXCAVATION --- AFTER EXCAVATION ---DEPTH(ft)0 1 2 3 4 SAMPLE TYPENUMBERPAGE 1 OF 1 SOIL PIT NUMBER TP 4 PROJECT NAME Singh 6th Street Short Plat PROJECT LOCATION 56XX NE 6th Street, Renton CLIENT Raman Sidhu PROJECT NUMBER 042113 GENERAL BH / TP / WELL - GINT STD US.GDT - 4/29/21 14:17 - F:\2021 PROJECTS\032112 SIDHU PLAT GEO\DATA\SIGNH 6TH STREET SHORT PLAT SOIL PITS.GPJINNOVATIVE GEO-SERVICES, LLC Engineering Geology and Septic Design 253 279-4205 rex@enggeologist.com U.S.C.S.MATERIAL DESCRIPTION GRAPHICLOGDocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh 6th Street Short Plat Geotechnical Evaluation April 29, 2021 Page 13 17903 82nd ST E, Bonney Lake, WA 98391 253 279-4205 c rex@enggeologist.com Soil Log Number: 3 Sheet 1 of 1 1. Site Address: 56XX NE 6th Street, Renton 2. Parcel Number: 102305170 3. Site Description: Glacial Terrace 4. List methods used to expose, sample, & test soils: Excavation of Test Pits and Field Examination 5. Number of test holes logged: 4 6. Saturated Percolation Rate: 10 in/hr. 7. Has fill material been placed over the proposed infiltration area? No 8. SCS Soil Series Alderwood 9. Hydrologic Soil Group C 10. Depth to seasonal high water: ➢ 4 ft. 11. Current water depth > 4 ft. 12. Depth to impermeable layer: >/= 4 ft. 13. Soil profile description: 1 – Dk Brown, Sandy Loam w/ gravel 2 - Lt Brown Sandy loam w/ gravel 3 – Glacial Till, gray, dry Horizon Depth Textural Class Mottling Induration 1 2 3 0 – 4 in. 4 - 36 in. 36 – 48 in IV IV IV - - Slight . I hereby state that I prepared this report and conducted or supervised the performance of related work. I state that I am qualified to do this work. I represent my work to be complete and accurate within the bounds of uncertainty inherent to the practice of soil science, and to be suitable for its intended use. Date: 04/29/2021 Registration No.: 1811 Stamp 4/29/2021 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 9 Custom Soil Resource Report Soil Map 5260180526020052602205260240526026052602805260300526032052601805260200526022052602405260260526028052603005260320564390 564410 564430 564450 564470 564490 564510 564530 564550 564570 564590 564610 564390 564410 564430 564450 564470 564490 564510 564530 564550 564570 564590 564610 47° 29' 35'' N 122° 8' 43'' W47° 29' 35'' N122° 8' 31'' W47° 29' 30'' N 122° 8' 43'' W47° 29' 30'' N 122° 8' 31'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 10N WGS84 0 50 100 200 300 Feet 0 15 30 60 90 Meters Map Scale: 1:1,090 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI AgB Alderwood gravelly sandy loam, 0 to 8 percent slopes 0.3 5.6% AgC Alderwood gravelly sandy loam, 8 to 15 percent slopes 4.5 94.4% Totals for Area of Interest 4.7 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, Custom Soil Resource Report 11 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 APPENDIX B: SITE PLAN DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 APPENDIX C: TEMPORARY EROSION AND SEDIMENT CONTROL PLAN DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 APPENDIX D: OPERATION & MAINTENANCE MANUAL DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 SIGNH 6TH STREETS SHORT PLAT STORM DRAINAGE FACILITIES OPERATION AND MAINTENANCE MANUAL Site Address: The development will occur on tax parcel number 1023059170. The existing residence on Lot 1 of this project’s short plat is located at 603 Nile Avenue NE in Renton, WA. The new residence on Lot 2 of this project’s short plat is located at 56XX NE 6th Street in Renton, WA. Introduction: This storm drainage report has been prepared to address the City of Renton’s site development and storm drainage requirements for the proposed Singh 6th Street Short Plat for parcel number 1023059170. The portion of the site that will be disturbed for construction has an area of approximately 0.225 acres. The subject site will be divided into two single-family lots and be developed by constructing of a new single-family residence and driveway with stormwater control features and frontage improvements for the new lots. According to the City of Renton’s standards for stormwater management, the City requires stormwater quantity and quality control for all proposed developments where they meet the thresholds in the City’s Surface Water Design Manual. We have proposed to construct dispersion systems consisting of infiltration trenches, splash blocks, dispersion trenches, yard drain/catch basins, and tightlines to address the required portion of the stormwater coming from the new impervious areas. Plan Goal: The specific purpose for the stormwater facility is to mitigate runoff from the proposed impervious areas. Attached to this narrative is a maintenance manual, which offers guidelines to the owner for stormwater facility maintenance. Prevention BMP’s: Any catch basins shall have stenciled on them “DUMP NO WASTE – DRAINS TO STREAM.” The owner shall be responsible for sweeping the lot, installing storm drainage stenciling and providing spill control procedures. In case of spill call the Washington State Department of Ecology at (425) 649-7000. The catch basins must be visually inspected for accumulation of debris and silt and will be maintained as required by this operation and maintenance manual and attachments. DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Maintenance Standards for Drainage Facilities: No. 2 – Infiltration Facilities No. 5 - Catch Basins No. 27 - Dispersion Trenches Treatment BMP’s: The City of Renton Utilities Section is to review and approve any changes to this Operation and Maintenance Manual prior to changes in its implementation. Additionally, any changes in ownership or person of responsibility are to be reported to the City Utilities Section. Inspection/Maintenance: Regular inspections of the drainage facilities should be carried out twice per year, in the spring and fall. The responsible party should keep records of these inspections available for review by the City. Additional inspections may be required after severe seasonal storms. Routine maintenance of the site will include mowing, care of landscaping, and the removal of trash and debris from the drainage system. The driveway should be kept clean and in repair. Events such as major storms or heavy winds will require immediate inspections for damages. Catch basins shall be cleaned when sump contains four inches or more of sediment or debris. Person of Responsibility: Harry Singh & Molly Sablok 603 Nile Ave NE Renton, WA 98059 Design Engineer: AP Consulting Engineers PLLC Adam E. Paul, PE PO Box 162 Auburn, WA 98071 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 INSPECTION/MAINTENANCE CHECKLIST STRUCTURE RESULTS/ MAINTENANCE DATE NOTES All Catch Basins Inspection results Maintenance Done Control Structures Inspection Results Maintenance Done Dispersion Trenches Inspection Results Maintenance Done The facility-specific maintenance standards that follow this checklist are intended to be conditions for determining through inspection if maintenance actions are required. Exceeding these conditions at any time between inspections and/or maintenance actions does not automatically constitute a violation of these standards. However, based upon inspection observations, the inspection and maintenance schedules shall be adjusted to minimize the length of time that a facility is in a condition that requires a maintenance action. DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 APPENDIX A MAINTENANCE REQUIREMENTS FOR FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES NO. 2 – INFILTRATION FACILITIES Maintenance Component Defect or Problem Conditions When Maintenance Is Needed Results Expected When Maintenance Is Performed Site Trash and debris Any trash and debris which exceed 1 cubic foot per 1,000 square feet (this is about equal to the amount of trash it would take to fill up one standard size office garbage can). In general, there should be no visual evidence of dumping. Trash and debris cleared from site. Noxious weeds Any noxious or nuisance vegetation which may constitute a hazard to County personnel or the public. Noxious and nuisance vegetation removed according to applicable regulations. No danger of noxious vegetation where County personnel or the public might normally be. Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries or paint. Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Grass/groundcover Grass or groundcover exceeds 18 inches in height. Grass or groundcover mowed to a height no greater than 6 inches. Infiltration Pond, Top or Side Slopes of Dam, Berm or Embankment Rodent holes Any evidence of rodent holes if facility is acting as a dam or berm, or any evidence of water piping through dam or berm via rodent holes. Rodents removed or destroyed and dam or berm repaired. Tree growth Tree growth threatens integrity of dams, berms or slopes, does not allow maintenance access, or interferes with maintenance activity. If trees are not a threat to dam, berm, or embankment integrity or not interfering with access or maintenance, they do not need to be removed. Trees do not hinder facility performance or maintenance activities. Erosion Eroded damage over 2 inches deep where cause of damage is still present or where there is potential for continued erosion. Any erosion observed on a compacted slope. Slopes stabilized using appropriate erosion control measures. If erosion is occurring on compacted slope, a licensed civil engineer should be consulted to resolve source of erosion. Settlement Any part of a dam, berm or embankment that has settled 4 inches lower than the design elevation. Top or side slope restored to design dimensions. If settlement is significant, a licensed civil engineer should be consulted to determine the cause of the settlement. Infiltration Pond, Tank, Vault, Trench, or Small Basin Storage Area Sediment accumulation If two inches or more sediment is present or a percolation test indicates facility is working at or less than 90% of design. Facility infiltrates as designed. Liner damaged (If Applicable) Liner is visible or pond does not hold water as designed. Liner repaired or replaced. Infiltration Tank Structure Plugged air vent Any blockage of the vent. Tank or vault freely vents. Tank bent out of shape Any part of tank/pipe is bent out of shape more than 10% of its design shape. Tank repaired or replaced to design. Gaps between sections, damaged joints or cracks or tears in wall A gap wider than ½-inch at the joint of any tank sections or any evidence of soil particles entering the tank at a joint or through a wall. No water or soil entering tank through joints or walls. Infiltration Vault Structure Damage to wall, frame, bottom, and/or top slab Cracks wider than ½-inch, any evidence of soil entering the structure through cracks or qualified inspection personnel determines that the vault is not structurally sound. Vault is sealed and structurally sound. 2016 Surface Water Design Manual – Appendix A 4/24/2016 A-3 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 APPENDIX A MAINTENANCE REQUIREMENTS FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES NO. 2 – INFILTRATION FACILITIES Maintenance Component Defect or Problem Conditions When Maintenance Is Needed Results Expected When Maintenance Is Performed Inlet/Outlet Pipes Sediment accumulation Sediment filling 20% or more of the pipe. Inlet/outlet pipes clear of sediment. Trash and debris Trash and debris accumulated in inlet/outlet pipes (includes floatables and non-floatables). No trash or debris in pipes. Damaged Cracks wider than ½-inch at the joint of the inlet/outlet pipes or any evidence of soil entering at the joints of the inlet/outlet pipes. No cracks more than ¼-inch wide at the joint of the inlet/outlet pipe. Access Manhole Cover/lid not in place Cover/lid is missing or only partially in place. Any open manhole requires immediate maintenance. Manhole access covered. Locking mechanism not working Mechanism cannot be opened by one maintenance person with proper tools. Bolts cannot be seated. Self-locking cover/lid does not work. Mechanism opens with proper tools. Cover/lid difficult to remove One maintenance person cannot remove cover/lid after applying 80 lbs of lift. Cover/lid can be removed and reinstalled by one maintenance person. Ladder rungs unsafe Missing rungs, misalignment, rust, or cracks. Ladder meets design standards. Allows maintenance person safe access. Large access doors/plate Damaged or difficult to open Large access doors or plates cannot be opened/removed using normal equipment. Replace or repair access door so it can opened as designed. Gaps, doesn't cover completely Large access doors not flat and/or access opening not completely covered. Doors close flat; covers access opening completely. Lifting Rings missing, rusted Lifting rings not capable of lifting weight of door or plate. Lifting rings sufficient to lift or remove door or plate. Infiltration Pond, Tank, Vault, Trench, or Small Basin Filter Bags Plugged Filter bag more than 1/2 full. Replace filter bag or redesign system. Infiltration Pond, Tank, Vault, Trench, or Small Basin Pre- settling Ponds and Vaults Sediment accumulation 6" or more of sediment has accumulated. Pre-settling occurs as designed Infiltration Pond, Rock Filter Plugged High water level on upstream side of filter remains for extended period of time or little or no water flows through filter during heavy rain storms. Rock filter replaced evaluate need for filter and remove if not necessary. Infiltration Pond Emergency Overflow Spillway Rock missing Only one layer of rock exists above native soil in area five square feet or larger, or any exposure of native soil at the top of out flow path of spillway. Rip-rap on inside slopes need not be replaced. Spillway restored to design standards. Tree growth Tree growth impedes flow or threatens stability of spillway. Trees removed. 4/24/2016 2016 Surface Water Design Manual – Appendix A A-4 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 APPENDIX A MAINTENANCE REQUIREMENTS FOR STORMWATER FACILITIES AND ON-SITE BMPS 12/12/2016 2017 City of Renton Surface Water Design Manual A-12 NO. 6 – CONVEYANCE PIPES AND DITCHES MAINTENANCE COMPONENT DEFECT OR PROBLEM CONDITIONS WHEN MAINTENANCE IS NEEDED RESULTS EXPECTED WHEN MAINTENANCE IS PERFORMED Pipes Sediment & debris accumulation Accumulated sediment or debris that exceeds 20% of the diameter of the pipe. Water flows freely through pipes. Vegetation/root growth in pipe Vegetation/roots that reduce free movement of water through pipes. Water flows freely through pipes. Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries or paint. Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Damage to protective coating or corrosion Protective coating is damaged; rust or corrosion is weakening the structural integrity of any part of pipe. Pipe repaired or replaced. Damaged pipes Any dent that decreases the cross section area of pipe by more than 20% or is determined to have weakened structural integrity of the pipe. Pipe repaired or replaced. Ditches Trash and debris Trash and debris exceeds 1 cubic foot per 1,000 square feet of ditch and slopes. Trash and debris cleared from ditches. Sediment accumulation Accumulated sediment that exceeds 20% of the design depth. Ditch cleaned/flushed of all sediment and debris so that it matches design. Noxious weeds Any noxious or nuisance vegetation which may constitute a hazard to City personnel or the public. Noxious and nuisance vegetation removed according to applicable regulations. No danger of noxious vegetation where City personnel or the public might normally be. Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries or paint. Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Excessive vegetation growth Vegetation that reduces free movement of water through ditches. Water flows freely through ditches. Erosion damage to slopes Any erosion observed on a ditch slope. Slopes are not eroding. Rock lining out of place or missing (If applicable) One layer or less of rock exists above native soil area 5 square feet or more, any exposed native soil. Replace rocks to design standards. DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 APPENDIX A MAINTENANCE REQUIREMENTS FOR FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES NO. 5 – CATCH BASINS AND MANHOLES Maintenance Component Defect or Problem Condition When Maintenance is Needed Results Expected When Maintenance is Performed Structure Sediment Sediment exceeds 60% of the depth from the bottom of the catch basin to the invert of the lowest pipe into or out of the catch basin or is within 6 inches of the invert of the lowest pipe into or out of the catch basin. Sump of catch basin contains no sediment. Trash and debris Trash or debris of more than ½ cubic foot which is located immediately in front of the catch basin opening or is blocking capacity of the catch basin by more than 10%. No Trash or debris blocking or potentially blocking entrance to catch basin. Trash or debris in the catch basin that exceeds 1/3 the depth from the bottom of basin to invert the lowest pipe into or out of the basin. No trash or debris in the catch basin. Dead animals or vegetation that could generate odors that could cause complaints or dangerous gases (e.g., methane). No dead animals or vegetation present within catch basin. Deposits of garbage exceeding 1 cubic foot in volume. No condition present which would attract or support the breeding of insects or rodents. Damage to frame and/or top slab Corner of frame extends more than ¾ inch past curb face into the street (If applicable). Frame is even with curb. Top slab has holes larger than 2 square inches or cracks wider than ¼ inch. Top slab is free of holes and cracks. Frame not sitting flush on top slab, i.e., separation of more than ¾ inch of the frame from the top slab. Frame is sitting flush on top slab. Cracks in walls or bottom Cracks wider than ½ inch and longer than 3 feet, any evidence of soil particles entering catch basin through cracks, or maintenance person judges that catch basin is unsound. Catch basin is sealed and is structurally sound. Cracks wider than ½ inch and longer than 1 foot at the joint of any inlet/outlet pipe or any evidence of soil particles entering catch basin through cracks. No cracks more than 1/4 inch wide at the joint of inlet/outlet pipe. Settlement/ misalignment Catch basin has settled more than 1 inch or has rotated more than 2 inches out of alignment. Basin replaced or repaired to design standards. Damaged pipe joints Cracks wider than ½-inch at the joint of the inlet/outlet pipes or any evidence of soil entering the catch basin at the joint of the inlet/outlet pipes. No cracks more than ¼-inch wide at the joint of inlet/outlet pipes. Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries or paint. Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Inlet/Outlet Pipe Sediment accumulation Sediment filling 20% or more of the pipe. Inlet/outlet pipes clear of sediment. Trash and debris Trash and debris accumulated in inlet/outlet pipes (includes floatables and non-floatables). No trash or debris in pipes. Damaged Cracks wider than ½-inch at the joint of the inlet/outlet pipes or any evidence of soil entering at the joints of the inlet/outlet pipes. No cracks more than ¼-inch wide at the joint of the inlet/outlet pipe. 2016 Surface Water Design Manual – Appendix A 4/24/2016 A-9 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 APPENDIX A MAINTENANCE REQUIREMENTS FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES NO. 5 – CATCH BASINS AND MANHOLES Maintenance Component Defect or Problem Condition When Maintenance is Needed Results Expected When Maintenance is Performed Metal Grates (Catch Basins) Unsafe grate opening Grate with opening wider than 7/8 inch. Grate opening meets design standards. Trash and debris Trash and debris that is blocking more than 20% of grate surface. Grate free of trash and debris. footnote to guidelines for disposal Damaged or missing Grate missing or broken member(s) of the grate. Any open structure requires urgent maintenance. Grate is in place and meets design standards. Manhole Cover/Lid Cover/lid not in place Cover/lid is missing or only partially in place. Any open structure requires urgent maintenance. Cover/lid protects opening to structure. Locking mechanism Not Working Mechanism cannot be opened by one maintenance person with proper tools. Bolts cannot be seated. Self-locking cover/lid does not work. Mechanism opens with proper tools. Cover/lid difficult to Remove One maintenance person cannot remove cover/lid after applying 80 lbs. of lift. Cover/lid can be removed and reinstalled by one maintenance person. 4/24/2016 2016 Surface Water Design Manual – Appendix A A-10 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 APPENDIX A MAINTENANCE REQUIREMENTS FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES NO. 27 – GRAVEL FILLED DISPERSION TRENCH BMP Maintenance Component Defect or Problem Conditions When Maintenance is Needed Results Expected When Maintenance is Performed Preventative Blocking, obstructions Debris or trash limiting flow to dispersion trench or preventing spreader function. Dispersion trench able to receive full flow prior to and during wet season. Site Trash and debris Trash or debris that could end up in the dispersion trench is evident. No trash or debris that could get into the dispersion trench can be found. Pipes Inlet is plugged The entrance to the pipe is restricted due to sediment, trash, or debris. The entrance to the pipe is not restricted. Vegetation/roots Vegetation/roots that reduce free movement of water through pipes. Water flows freely through pipes. Plugged Sediment or other material prevents free flow of water through the pipe. Water flows freely through pipes. Broken joint or joint leaks. Damage to the pipe or pipe joints allowing water to seep out. Pipe does not allow water to exit other than at the outlet to the trench. Cleanout caps Cleanout caps are broken, missing, or buried. Cleanout caps are accessible and intact. Structure Flow not reaching trench Flows are not getting into the trench as designed. Water enters and exits trench as designed. Perforated pipe plugged Flow not able to enter or properly exit from perforated pipe. Water freely enters and exits perforated pipe. Flow not spreading evenly at outlet of trench Outlet flows channelizing or not spreading evenly from trench. Sheet flow occurs at the outlet of the trench. Cleanout/inspection access does not allow cleaning or inspection of perforated pipe The cleanout/inspection access is not available. Cleanout/inspection access is available. Filter Media Filter media plugged Filter media plugged. Flow through filter media is normal. Inspection Frequency Annually and prior to and following significant storms. Inspect dispersion trench system for any defects of deficiencies. 4/24/2016 2016 Surface Water Design Manual – Appendix A A-36 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 APPENDIX E: DOWNSTREAM ANALYSIS DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 2,108.4 ft 156.9 ft156.9 ft287.1 ft287.1 ft204.3 ft204.3 ft70.5 ft70.5 ft174.8 ft174.8 ft 420.6 ft420.6 ft 794.3 ft King County King County iMap Date: 6/17/2020 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.± Head of Honey Creek Analysis ends 1/4 mile from project site Pond outflows north to Honey Creek Exg storm system outfall to detention pond. Exg CB at corner of Mount Baker Ave and 6th St. Existing roadside drainage ditch along the north side of NE 6th St. Stormwater enters the ditch from 4 CBs along 6th St and flows west. Project Location DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 APPENDIX F: WWHM REPORT DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 WWHM2012 PROJECT REPORT DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:05:16 PM Page 2 General Model Information Project Name:Singh6thstreetSP_11.23.2021 Site Name:Nile Lot 2 Site Address: City: Report Date:12/7/2021 Gage:Seatac Data Start:1948/10/01 Data End:2009/09/30 Timestep:15 Minute Precip Scale:1.167 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 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:05:16 PM Page 3 Landuse Basin Data Predeveloped Land Use Basin 1 Bypass:No GroundWater:No Pervious Land Use acre C, Forest, Mod 0.33 Pervious Total 0.33 Impervious Land Use acre Impervious Total 0 Basin Total 0.33 Element Flows To: Surface Interflow Groundwater DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:05:16 PM Page 4 Mitigated Land Use Basin 1 Bypass:No GroundWater:No Pervious Land Use acre C, Lawn, Flat 0.157 Pervious Total 0.157 Impervious Land Use acre ROOF TOPS FLAT 0.037 DRIVEWAYS FLAT 0.035 SIDEWALKS FLAT 0.047 Impervious Total 0.119 Basin Total 0.276 Element Flows To: Surface Interflow Groundwater DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:05:16 PM Page 5 Routing Elements Predeveloped Routing DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:05:16 PM Page 6 Mitigated Routing DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:05:16 PM Page 7 Analysis Results POC 1 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area:0.33 Total Impervious Area:0 Mitigated Landuse Totals for POC #1 Total Pervious Area:0.157 Total Impervious Area:0.119 Flow Frequency Method:Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.013601 5 year 0.023116 10 year 0.030683 25 year 0.041685 50 year 0.050937 100 year 0.061102 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.072879 5 year 0.099017 10 year 0.117405 25 year 0.141897 50 year 0.161071 100 year 0.181055 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1949 0.020 0.108 1950 0.021 0.099 1951 0.027 0.066 1952 0.009 0.043 1953 0.007 0.046 1954 0.011 0.060 1955 0.017 0.065 1956 0.015 0.062 1957 0.014 0.081 1958 0.012 0.055 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:05:57 PM Page 8 1959 0.011 0.048 1960 0.021 0.067 1961 0.010 0.066 1962 0.007 0.047 1963 0.010 0.066 1964 0.014 0.058 1965 0.011 0.083 1966 0.008 0.049 1967 0.023 0.099 1968 0.013 0.101 1969 0.012 0.079 1970 0.010 0.069 1971 0.013 0.080 1972 0.021 0.102 1973 0.010 0.041 1974 0.013 0.078 1975 0.016 0.081 1976 0.012 0.059 1977 0.005 0.063 1978 0.010 0.070 1979 0.006 0.087 1980 0.037 0.114 1981 0.008 0.075 1982 0.022 0.120 1983 0.014 0.078 1984 0.009 0.054 1985 0.005 0.074 1986 0.022 0.064 1987 0.020 0.090 1988 0.009 0.046 1989 0.005 0.062 1990 0.063 0.175 1991 0.029 0.133 1992 0.011 0.053 1993 0.010 0.042 1994 0.004 0.040 1995 0.013 0.062 1996 0.035 0.083 1997 0.025 0.076 1998 0.010 0.063 1999 0.040 0.161 2000 0.010 0.074 2001 0.002 0.070 2002 0.014 0.105 2003 0.023 0.085 2004 0.022 0.148 2005 0.015 0.066 2006 0.015 0.061 2007 0.048 0.159 2008 0.049 0.130 2009 0.021 0.082 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.0628 0.1745 2 0.0489 0.1612 3 0.0481 0.1586 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:05:57 PM Page 9 4 0.0403 0.1476 5 0.0371 0.1328 6 0.0354 0.1301 7 0.0287 0.1198 8 0.0267 0.1142 9 0.0253 0.1079 10 0.0232 0.1052 11 0.0232 0.1018 12 0.0218 0.1010 13 0.0217 0.0991 14 0.0216 0.0986 15 0.0213 0.0904 16 0.0212 0.0872 17 0.0209 0.0846 18 0.0208 0.0832 19 0.0201 0.0831 20 0.0198 0.0818 21 0.0167 0.0811 22 0.0164 0.0805 23 0.0154 0.0802 24 0.0150 0.0788 25 0.0147 0.0784 26 0.0142 0.0776 27 0.0139 0.0760 28 0.0135 0.0752 29 0.0135 0.0744 30 0.0134 0.0744 31 0.0128 0.0700 32 0.0128 0.0698 33 0.0126 0.0690 34 0.0125 0.0671 35 0.0120 0.0664 36 0.0119 0.0658 37 0.0113 0.0657 38 0.0108 0.0656 39 0.0106 0.0646 40 0.0105 0.0642 41 0.0103 0.0633 42 0.0101 0.0626 43 0.0100 0.0623 44 0.0098 0.0620 45 0.0097 0.0617 46 0.0097 0.0607 47 0.0096 0.0604 48 0.0096 0.0592 49 0.0089 0.0580 50 0.0087 0.0550 51 0.0085 0.0539 52 0.0084 0.0534 53 0.0083 0.0493 54 0.0075 0.0479 55 0.0070 0.0471 56 0.0057 0.0463 57 0.0055 0.0456 58 0.0051 0.0428 59 0.0050 0.0422 60 0.0043 0.0409 61 0.0025 0.0395 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:05:57 PM Page 10 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:05:57 PM Page 11 Duration Flows Flow(cfs)Predev Mit Percentage Pass/Fail 0.0068 16208 66070 407 Fail 0.0072 14117 60381 427 Fail 0.0077 12192 55183 452 Fail 0.0081 10508 50649 482 Fail 0.0086 9163 46521 507 Fail 0.0090 7961 42820 537 Fail 0.0095 6949 39527 568 Fail 0.0099 6141 36425 593 Fail 0.0104 5454 33709 618 Fail 0.0108 4864 31163 640 Fail 0.0113 4368 28832 660 Fail 0.0117 3921 26715 681 Fail 0.0122 3480 24747 711 Fail 0.0126 3091 22972 743 Fail 0.0130 2731 21293 779 Fail 0.0135 2421 19836 819 Fail 0.0139 2160 18429 853 Fail 0.0144 1938 17184 886 Fail 0.0148 1761 16029 910 Fail 0.0153 1597 14970 937 Fail 0.0157 1395 14001 1003 Fail 0.0162 1246 13062 1048 Fail 0.0166 1122 12192 1086 Fail 0.0171 1036 11422 1102 Fail 0.0175 941 10688 1135 Fail 0.0179 876 10023 1144 Fail 0.0184 788 9396 1192 Fail 0.0188 716 8825 1232 Fail 0.0193 633 8316 1313 Fail 0.0197 548 7895 1440 Fail 0.0202 465 7424 1596 Fail 0.0206 391 6994 1788 Fail 0.0211 351 6562 1869 Fail 0.0215 309 6171 1997 Fail 0.0220 265 5799 2188 Fail 0.0224 218 5482 2514 Fail 0.0229 183 5180 2830 Fail 0.0233 153 4877 3187 Fail 0.0237 126 4635 3678 Fail 0.0242 113 4376 3872 Fail 0.0246 93 4132 4443 Fail 0.0251 80 3910 4887 Fail 0.0255 67 3692 5510 Fail 0.0260 60 3514 5856 Fail 0.0264 49 3349 6834 Fail 0.0269 44 3159 7179 Fail 0.0273 41 3012 7346 Fail 0.0278 35 2838 8108 Fail 0.0282 30 2699 8996 Fail 0.0286 25 2579 10316 Fail 0.0291 20 2451 12255 Fail 0.0295 18 2338 12988 Fail 0.0300 12 2246 18716 Fail 0.0304 12 2147 17891 Fail DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:05:57 PM Page 12 0.0309 11 2047 18609 Fail 0.0313 11 1958 17800 Fail 0.0318 10 1871 18710 Fail 0.0322 9 1790 19888 Fail 0.0327 9 1715 19055 Fail 0.0331 9 1643 18255 Fail 0.0335 9 1574 17488 Fail 0.0340 9 1517 16855 Fail 0.0344 9 1466 16288 Fail 0.0349 9 1411 15677 Fail 0.0353 9 1359 15100 Fail 0.0358 8 1307 16337 Fail 0.0362 8 1251 15637 Fail 0.0367 8 1200 15000 Fail 0.0371 7 1153 16471 Fail 0.0376 6 1110 18500 Fail 0.0380 6 1079 17983 Fail 0.0385 6 1028 17133 Fail 0.0389 6 992 16533 Fail 0.0393 6 953 15883 Fail 0.0398 6 916 15266 Fail 0.0402 6 879 14650 Fail 0.0407 5 860 17200 Fail 0.0411 5 829 16580 Fail 0.0416 5 802 16039 Fail 0.0420 5 773 15460 Fail 0.0425 5 752 15039 Fail 0.0429 5 730 14600 Fail 0.0434 5 702 14039 Fail 0.0438 5 681 13620 Fail 0.0442 4 662 16550 Fail 0.0447 4 639 15975 Fail 0.0451 4 620 15500 Fail 0.0456 4 602 15050 Fail 0.0460 4 577 14425 Fail 0.0465 4 554 13850 Fail 0.0469 4 541 13525 Fail 0.0474 4 523 13075 Fail 0.0478 4 504 12600 Fail 0.0483 3 489 16300 Fail 0.0487 3 474 15800 Fail 0.0492 1 462 46200 Fail 0.0496 1 454 45400 Fail 0.0500 1 442 44200 Fail 0.0505 1 428 42800 Fail 0.0509 1 416 41600 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. DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:05:57 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. DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:05:57 PM Page 14 LID Report DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:06:26 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. DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:06:26 PM Page 16 Appendix Predeveloped Schematic DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:06:26 PM Page 17 Mitigated Schematic DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:06:27 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 Singh6thstreetSP_11.23.2021.wdm MESSU 25 PreSingh6thstreetSP_11.23.2021.MES 27 PreSingh6thstreetSP_11.23.2021.L61 28 PreSingh6thstreetSP_11.23.2021.L62 30 POCSingh6thstreetSP_11.23.20211.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 11 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 *** 11 C, 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 *** 11 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 ********* 11 0 0 4 0 0 0 0 0 0 0 0 0 1 9 END PRINT-INFO DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:06:27 PM Page 19 PWAT-PARM1 <PLS > PWATER variable monthly parameter value flags *** # - # CSNO RTOP UZFG VCS VUZ VNN VIFW VIRC VLE INFC HWT *** 11 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 11 0 4.5 0.08 400 0.1 0.5 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 11 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 11 0.2 0.5 0.35 6 0.5 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 11 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 *** 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 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:06:27 PM Page 20 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Basin 1*** PERLND 11 0.33 COPY 501 12 PERLND 11 0.33 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 1.167 PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1.167 IMPLND 1 999 EXTNL PREC DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:06:27 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 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:06:27 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 Singh6thstreetSP_11.23.2021.wdm MESSU 25 MitSingh6thstreetSP_11.23.2021.MES 27 MitSingh6thstreetSP_11.23.2021.L61 28 MitSingh6thstreetSP_11.23.2021.L62 30 POCSingh6thstreetSP_11.23.20211.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 16 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 *** 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 ********* DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:06:27 PM Page 23 16 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 *** 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 *** 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 *** 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 ********* 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 *** 4 0 0 0 0 0 5 0 0 0 0 0 8 0 0 0 0 0 END IWAT-PARM1 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:06:27 PM Page 24 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 8 400 0.01 0.1 0.1 END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN 4 0 0 5 0 0 8 0 0 END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 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 16 0.157 COPY 501 12 PERLND 16 0.157 COPY 501 13 IMPLND 4 0.037 COPY 501 15 IMPLND 5 0.035 COPY 501 15 IMPLND 8 0.047 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 *** DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:06:27 PM Page 25 # - # 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 1.167 PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1.167 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 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:06:27 PM Page 26 Predeveloped HSPF Message File DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:06:27 PM Page 27 Mitigated HSPF Message File DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390 Singh6thstreetSP_11.23.2021 12/7/2021 3:06:27 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. 2005-2021; 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 DocuSign Envelope ID: 3B4D7BC6-B0BD-4F97-B0A2-27226522A390