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HomeMy WebLinkAboutORD 5611CITY OF RENTON, WASHINGTON ORDINANCE NO. 5611 AN ORDINANCE OF THE CITY OF RENTON, WASHINGTON, ADOPTING BY REFERENCE THE SUNSET AREA SURFACE WATER MASTER PLAN. WHEREAS, the Council has heretofore adopted stormwater controls for the City of Renton; and WHEREAS, adoption of a comprehensive system of stormwater controls for the Sunset Area has been reviewed in the Sunset Area Draft Environmental Impact Statement issued in December 2010, and in the Sunset Area Final Environmental Impact Statement issued in April 2011; and WHEREAS, the City is simultaneously adopting the Sunset Area Planned Action ordinance which requires implementation of a comprehensive system of stormwater controls for the Sunset Area in the best interest of, and for public benefit; and WHEREAS, the City has held a public hearing on this matter on April 6, 2011; and WHEREAS, the Planning Commission has made certain findings and recommendations to the Council; and WHEREAS, the Council has duly determined after due consideration of the evidence before it that it is advisable and appropriate to adopt the Sunset Area Surface Water Master Plan; NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF RENTON, WASHINGTON, DOES ORDAIN AS FOLLOWS: SECTION I. The above findings and recitals are found to be true and correct in all respects. ORDINANCE NO. 5611 SECTION 11. The Sunset Area Surface Water Master Plan, as shown on Attachment A and incorporated herein as if fully set forth, is herby adopted by this reference. SECTION III. This ordinance shall be effective upon its passage, approval, and five (5) days after publication. PASSED BY THE CITY COUNCIL this 13th day of June , 2011. Bonnie I. Walton, City Clerk APPROVED BY THE MAYOR this 13th day of June , 2011. ^....4^iA>c> ( / £IA Denis Law, Mayor Approved as to form: Lawrence J. Warren, City Attorney Date of Publication: 6/17/2011 (summary) '* u ORD:1707:4/12/ll:scr 2 ORDINANCE NO. 5611 ATTACHMENT A SUNSET AREA SURFACE WATER MASTER PLAN ORDINANCE NO. 5611 CITY COUNCIL REVIEW DRAFT Sunset Area Surface Water Master PI Prepared for City of Renton Prepared by CH2IVIHILL 1100 112th Avenue NE Bellevue, WA 98004 April 2011 ORDINANCE NO. 5611 i Contents 2 Contents iii 3 1 Introduction 1 4 Purpose 1 5 Planned Action Study Area 1 6 Community Input 1 7 Priority Levels 2 8 2 Study Area Characteristics 3 9 Drainage Basins and Land Cover 3 10 Groundwater 7 11 Drainage System 7 12 3 Applicable Regulations 9 13 Federal 9 14 State 9 15 Local 9 16 Sunset Area Revised Flow Control Strategy 10 17 4 Proposed Projects 13 18 Green Connections 13 19 Sunset Terrace Sub-Regional Facility 19 20 Conveyance Improvements 21 21 5 Project Implementation 25 22 Project Planning Cost Estimate 26 23 6 References 29 24 \\SIMBA\PROJ\RENTONWACITYOR408314\9_STORMWATEro 21_C0UNCILREVIEWDRAFT.D0CX || CONTENTS ORDINANCE NO. 5611 1 Tables 2 1 Targeted Level of Flow Control Mitigation by Public Infrastructure Projects 3 2 Priority Level 1 Projects and Costs 4 3 Priority Level 2 Projects and Costs 5 Figures 6 1 Drainage Basins 7 2 Soil Types & Aquifer Protection Zone 8 3 Steep Slope Areas 9 4 Green Connections 10 5 Typical Sections for Harrington and Jefferson Avenue NE 11 6 Typical Sections for Edmonds Avenue NE and NE 12th Street 12 7 Sub-Regional Flow Control Facility 13 8 Proposed Stormwater Drainage Conveyance System 14 Appendices 15 A. Summary of Expected New Effective Impervious Area 16 B. Summary of Peak Flow Rates for the Study Area 17 C. Opinion of Cost 18 D. Hydrologic and Hydraulic Model Output IV SUNSETAREA_SURFACEWATER_UASTERPUN_0421_COUNCILREVIEWDRAFT.DOCX ORDINANCE NO. 5611 1 1 Introduction 2 Purpose 3 This Surface Water Master Plan was written to guide the City of Renton's surface water 4 management program within the Sunset Planned Action Study Area. It also identifies 5 surface water projects and priority needs and develop long-term solutions that meet 6 regulatory requirements, reflect the community's priorities, and can be funded by the City 7 or through future developments. A study was conducted in support of this master plan to 8 evaluate surface water infrastructure improvements necessary to support the 9 redevelopment of the Sunset Terrace public housing community and associated 10 neighborhood growth and revitalization, including other public service and infrastructure 11 improvements (e.g., transportation improvements). This Surface Water Master Plan is 12 prepared in conjunction with a Sunset Terrace Planned Action Environmental Impact 13 Statement. 15 The study area for the Surface Water Master Plan is generally bounded by NE 21st Street on 16 the north, Monroe Avenue NE on the east, NE 7th Street on the south, and Edmonds 17 Avenue NE on the west. The development of the study area started in the mid 1940's. The 18 City utilities, includes storm drains, serving the area were installed as the area developed. 19 The age of some of the existing storm drains infrastructure is estimated to be more than fifty 20 years old. The study area land uses include mixed-use, mixed-income residential, 21 commercial, and retail properties. The businesses are primarily located along Sunset 22 Boulevard and NE 12th Street. 23 The Sunset Area Community Investment Strategy developed by the City of Renton in 2009 24 identified several residential streets in the neighborhood, designated as "Green 25 Connections," that would be transformed to improve pedestrian and bicyclist mobility, 26 improve stormwater quality, mitigate the quantity of stormwater runoff, and create an 27 inviting corridor to enhance the neighborhood. 29 In 2009, a Sunset Community Investment Strategy (CIS) was initiated to create a blueprint 30 for the public investment that can be coordinated and phased in over the coming years. 31 Some of the projects listed below were based on the result of the CIS. Elements of the 32 Surface Water Master Plan were also included in the Planned Action environmental impact 33 statement process, which includes scoping meetings and comment periods, the Draft 34 Environmental Impact Statement (EIS) and comments, and responses to comments in the 14 Planned Action Study Area 28 Community Input 35 Final EIS. SUNSETAREA_SURFACEWATER_MASTERPLAN_0421_COUNCILREVIEWDRAFT.DOCX ORDINANCE NO. 5611 1 INTRODUCTION 1 Priority Levels 2 Priority levels were assigned to projects identified in this plan. These priority levels are 3 intended to inform decisions on the timing of the projects and the expenditure of limited 4 resources, and are defined as follows: 5 Priority Level 1: Projects with priority level 1 are deemed critical because they 6 address an immediate system deficiency or coincide with redevelopment of Sunset 7 Terrace or other public infrastructure improvements to support the potential 8 redevelopment. For example, the Harrington Avenue Green Connections projects, 9 which improve pedestrian mobility and safety between important public spaces and 10 schools within the Sunset Area, are priority level 1. 11 Priority Level 2: Priority level 2 projects are not immediately necessary and could be 12 implemented to support redevelopment or to reduce costs by constructing them 13 concurrently with other public infrastructure improvements, e.g. lower priority 14 Green Connections. 2 SUNSETAREA_SURFACEWATER_MASTERPLAN_0421_COUNCILREVIEWDRAFT.DOCX ORDINANCE NO. 5611 i 2 Study Area Characteristics 2 Drainage Basins and Land Cover 3 The Planned Action Study Area is currently developed for residential and commercial land 4 uses. In general, the stormwater runoff from this area drains to roadside ditches, catch 5 basins, and storm drains. The runoff is collected and conveyed into larger storm drains 6 within the major streets and discharges into local creeks and drainage tributaries. No 7 stream, water body, or water-related critical area is located in or immediately adjacent to the 8 Planned Action Study Area, and no local flooding has been reported in the area. The Study 9 Area is not within a special flood hazard area mapped by the Federal Emergency 10 Management Agency (FEMA). 11 The Planned Action Study Area comprises approximately 269 acres of urban developed 12 area. The area drains to three tributary creeks: Honey Creek, May Creek (Lower May 13 Creek), and Johns Creek. All three creeks are part of the Greater Lake Washington 14 Watershed (Water Resources Inventory Area [WRIA] 8 in King County). Lake Washington, 15 the receiving water body from May Creek and Johns Creek, is the second largest natural 16 lake in Washington. Most of the immediate watershed is highly developed and urban, with 17 63 percent fully developed. 18 Approximately three (3) acres at the northeast corner of the study area drain to Honey 19 Creek, which is a tributary to May Creek. The northwest corner of the study area, which 20 includes 23 acres of primarily single-family residential land use, drains to May Creek. The 21 balance of the study area, approximately 243 acres of mixed single-family residential, 22 multifamily residential, and commercial uses, drains to Johns Creek (Figure 1). The existing 23 and preferred alternatives land cover summary are shown in Table A-2 in Appendix A. 24 Soil 25 The soils influencing the design and function of the study area generally consist of urban 26 soils (largely fill) and glacially derived outwash and till deposits. Figure 2 shows the surface 27 soil as mapped by the Natural Resources Conservation Service. The northern and southern 28 area consists of outwash soil, which is generally very permeable and has a good infiltration 29 rate. The central and western portion of the study area generally consists of till soil, which is 30 a dense, unsorted mixture of gravel, sand, silt, and clay. Till soil is less permeable than 31 outwash soil and has limited infiltration capacity. Much of the central portion of the study 32 area is designated as urban soils, which are difficult to classify due to the variable nature of 33 the soil; however, for the purposes of this study, urban soils are assumed to exhibit similar 34 infiltration characteristics as till soil. Figure 2 shows the soil conditions of the study area. 35 Figure 3 shows the area of steep slopes where an infiltration facility is not allowed per City 36 of Renton code. SUNSETAREA_SURFACEWATER_MASTERPLAN_0421_COUNCILREVIEWDRAFT.DOCX 3 ORDINANCE NO. 5611 CM2MHILL Figure 1 DRAINAGE BASINS City of Renton Sunset Area Master Drainage Plan ORDINANCE NO. 5611 / C3 Planned Action Study Area 7y CZH Parcels / BlAauiferProtection ^ Soil Types Outwash U LZlTill n CH2IWHILL Figure 2 Soil Types & Aquifer Protection Zone City of Renton Sunset Area Master Drainage Plan Pl.innod Ar Lion Study Area i Slope Range 1.5-2!)°., 7.^25-40% -•40" , N A 0 GOO 1,200 Feet IMS ORDINANCE NO. 5611 • v ;k. «g» CH2MHILL Figure 3 Steep Slope Hazard Areas City of Renton Sunset Area Master Drainage Plan ORDINANCE NO. 5611 2 STUDY AREA CHARACTERISTICS 1 Groundwater 2 The Planned Action Study Area is within the City's Aquifer Protection Zone 2. The 3 protection areas are the portions of an aquifer within the zone of capture, and the recharge 4 area for wells owned or operated by the City. Zone 2 is the land area situated between the 5 365-day groundwater travel time contour and the boundary of the zone of potential capture 6 wells. This aquifer is the sole drinking water source for the City of Renton. The Planned 7 Action Study Area south of Sunset Boulevard lies within the source area of Cedar Valley 8 Sole Source Aquifer, designated by the U.S. Environmental Protection Agency, which is also 9 part of the City's Aquifer Protection Zone 2. The limits of the Aquifer Protection Zone and 10 infiltration potential within the study area are presented in Figure 2. 11 Drainage System 12 May Creek Basin 13 Approximately 26 acres within the northern portion of the study area drain to the May 14 Creek Basin. This area is largely developed under single-family residential land use. There is 15 one storm drain system in the study area in May Creek Basin. This system extends along NE 16 16th Street beginning west of Index Avenue NE and drains westward and then north on 17 Edmonds Avenue NE. This system eventually drains to May Creek. 18 May Creek is 7 miles long and originates in the steep forested slopes of Cougar and Squak 19 mountains and in the highlands of the Renton Plateau. The entire basin encompasses an 20 area of fourteen (14) square miles that drains to the southeast portion of Lake Washington 21 (City of Renton and King County 2001). The May Creek Basin also includes other tributaries: 22 Honey Creek, Boren Creek, and the north, east, and south forks of May Creek. May Creek 23 and its tributaries are designated by Washington Department of Ecology (Ecology) as "Class 24 AA" (superior) because May Creek is a feeder stream to Lake Washington. Class AA waters 25 can be used for water supply (domestic, industrial, and agricultural), stock watering, fish 26 spawning, wildlife habitat, and recreation (Foster Wheeler Environmental 1995). 27 Johns Creek Basin 28 Most of the study area is within the John's Creek Basin. The land use in this basin is mainly 29 single-family residential, schools, and commercial/ industrial development. A small portion 30 is used for multi-family or high-density housing. The upper basin is dominated by 31 residential and commercial land use, and the lower basin is dominated by industrial and 32 commercial uses. 33 Johns Creek discharges to Lake Washington at Gene Coulon Park in Renton. Johns Creek 34 extends upstream in a southeasterly direction for less than 1 mile. Because of its proximity 35 to Lake Washington, the stream water elevation is controlled by Lake Washington, and 36 therefore it is considered to be a major receiving water body per the City amendment to the 37 King County Surface Water Design Manual (City of Renton 2010a). The Johns Creek Basin 38 covers approximately 1,236 acres and is located east of the Cedar River, in the northeastern 39 portion of Renton. The drainage system serving the overall basin consists primarily of SUNSETAREA_SURFACEWATER_MASTERPLAN_0421_COUNCILREVIEWDRAFT.DOCX 7 STUDY AREA CHARACTERISTICS ORDINANCE NO. 5611 1 roadside ditches and storm drain pipes. There are three primary storm drainage systems in 2 this basin: Sunset Boulevard, NE 9th Street, and NE 7th Street. 3 Sunset Boulevard Storm Drainage System 4 Record drawings indicate tire Sunset Boulevard (SR 900) storm drainage system was 5 constructed in the 1970s. The system consists of 30-inch-diameter pipe downstream of the 6 study area, west of Edmonds Avenue NE. The main trunk of the storm drainage system 7 extends along Sunset Boulevard. This storm drain directly collects runoff from Sunset 8 Boulevard and adjacent properties. This trunk also receives flows from drainage systems on 9 adjacent streets and a 12-inch diameter storm drain on Harrington Avenue NE (south of NE 10 10th Street) was constructed in the 1950s. 11 This system also conveys runoff from Edmonds Avenue NE between Sunset Boulevard and 12 south of NE 16th Street, Harrington Avenue NE, and NE 10th Street immediately north of 13 Sunset Boulevard. The Edmonds Avenue NE system conveys runoff from the NE 12th Street 14 system, Harrington Avenue NE system, Jefferson Avenue NE, and Kirkland Avenue NE. 15 The NE 12th Street system was upgraded in the early 1980s into 36-inch-diameter pipe from 16 Kirkland Avenue NE to Edmonds Avenue NE. The system remains as 12-inch-diameter 17 pipe east of Kirkland Avenue NE. The Kirkland Avenue NE system is a 12-inch-diameter 18 pipe that starts at NE 16th Avenue. It was built pre-1950. Currentiy, the stormwater runoff 19 from Harrington Avenue NE and Jefferson Avenue flows on the street surface and is 20 intercepted by the storm drain on NE 12th Street. 21 NE 9th Street Storm Drainage System 22 The NE 9th Street system drains the area south of Sunset Boulevard to NE 9th Street. It 23 starts west of Monroe Avenue NE and drains west. It intercepts a storm drain at Harrington 24 Avenue NE. The combined system continues to flow west, then turns north at Ferndale 25 Circle NE, then turns west and becomes an 18-inch-diameter pipe. This system turns west 26 again, crossing under Edmonds Avenue NE toward NE 9thh Place. 27 NE 7th Street Storm Drainage System 28 The NE 7th Street system starts east of the study area from Monroe Avenue NE. This system 29 drains west and intercepts two storm drains at Harrington Avenue NE. Only a small portion 30 of the study area drains into this storm drain. 8 SUNSETAREA_SURFACEWATER_MASTERPLAN_0421_COUNCILREVIEWDRAFT.DOCX ORDINANCE NO. 5611 1 3 Applicable Regulations 2 This chapter summarizes the federal, state, and local stormwater regulations that all 3 developments should comply with. Also, the Sunset Terrance Area specific flow control 4 strategy is discussed. 5 Federal 6 Federal stormwater regulations in the Clean Water Act (33 U.S.C. §1251 et seq.) are typically 7 promulgated through local stormwater requirements (see below). Projects proposed as part 8 of the Sunset Area Surface Water Master Plan will need to meet the requirements of Section 9 7 of the Endangered Species Act (16 U.S.C. §1531 et seq.), which is regulated by the U.S. 10 Department of the Interior, National Marine Fisheries Service, and U.S. Fish and Wildlife 11 Service. 12 State 13 For projects with an area of disturbance exceeding one (1) acre, the City is required to file a 14 Notice of Intent with Ecology for coverage under the National Pollutant Discharge 15 Elimination System (NDPES) program's General Permit for Stormwater Discharges 16 Associated with Construction Activities. These filings typically require projects to provide 17 erosion-control measures consistent with Ecology's Stormwater Management Manual for 18 Western Washington (Ecology 2005). 19 The City of Renton is required to administer a stormwater management program developed 20 in accordance with the Western Washington Municipal Stormwater NDPES phase II Permit. 21 Among the specific obligations set forth in this NDPEs permit, the City is required to adopt 22 by ordinance a stormwater design manual that is equivalent to the 2005 Ecology manual. 23 Therefore, the City has adopted the 2009 King County Surface Water Design Manual with 24 City amendments (City of Renton 2010a) for the design, construction, and maintenance of 25 stormwater management systems and facihties that are approved through the development 26 permit process. Permanent stormwater features must meet the manual's design standards 27 or be equivalent. 28 Local 29 RMC 4-3-050, Critical Areas Regulations, addresses the requirements for development 30 within or adjacent to the aquifer protection areas or any other critical area (i.e., flood hazard 31 areas, erosion hazard areas, wetland, streams, etc). 32 Renton Municipal Code (RMC) 4-6-030 and Ordinance No. 5526 address storm drain 33 utilities. Technical requirements for the design of stormwater facilities are contained in the 34 King County Surface Water Design Manual (King County 2009) and the City amendments to 35 tire manual (City of Renton 2010). SUNSETAREA_SURFACEWATER_UASTERPLAN_0421_COUNCILREVIEWDRAFT.DOCX 9 ORDINANCE NO. 5611 3 APPLICABLE REGULATIONS 1 The City's drainage (surface water) management standards are focused on reducing 2 potential impacts from new impervious surfaces, replaced impervious surface, new 3 pervious surface, and land disturbing activity (2009 KCSWDM and City Amendment). 4 Redevelopment and new development exceeding the thresholds specified in the 2009 5 KCSWDM (as amended by the City) are required to comply with the requirements set forth 6 in the manual, including stormwater treatment and flow control BMPs. The majority of the 7 Planned Action Study Area was developed prior to the advent of modern stormwater 8 requirements (e.g., implementation of the 1990 King County Surface Water Design Manual) or 9 under less stringent requirements. 10 The drainage (surface water) standards also require the use of flow-control best 11 management practices (BMPs), where feasible. Flow-control BMPs include many low- 12 impact development techniques such as infiltration, dispersion, rain gardens, permeable 13 pavements, vegetative roofs, rainfall harvesting, reduction of impervious area, and retention 14 of native vegetation. Projects should implement full dispersion or full infiltration of roof 15 runoff where feasible. Where runoff from impervious surfaces cannot feasibly be dispersed 16 or infiltrated, the code requires that a minimum portion of the site or impervious area be 17 managed through these practices. Small lots of less than 22,000 square feet are required to 18 provide either full infiltration/dispersion of stormwater, where feasible, or, where not 19 feasible, provide flow-control BMPs for an impervious area equal to 10 percent of the site 20 area (for lots smaller than 11,000 square feet) or 20 percent of the site area (for lots between 21 11,000 square feet and 22,000 square feet). For lots larger than 22,000 square feet, the total 22 allowable impervious area exceeds 65 percent for all zoning classifications; therefore, all 23 potential new or redevelopment projects within the study area are required to comply with 24 the flow-control requirements for Large Lot High Impervious BMP requirements that 25 require flow-control BMPs to manage 10 percent of the site or 20 percent of the target 26 impervious surface, whichever is less. The flow control BMP requirement shall be applied to 27 the project site regardless to whether a flow control facility is required. Additional flow 28 controls may be required within the Johns Creek Basin to match peak flows under existing 29 conditions. Areas within May Creek and Honey Creek basins are required to comply with 30 the more stringent Flow Control Duration Standard, which the stormwater runoff release 31 from the site requires matching forested predevelopment conditions. 32 Sunset Area Revised Flow Control Strategy 33 Redevelopment in the study area will comply with all the stormwater regulations and 34 requirements (federal, state and City of Renton). Proposed development and redevelopment 35 projects will provide flow control BMPs (AKA low-impact development practices) onsite as 36 feasible, and water quality treatment onsite. The sub-regional facility and Green 37 Connections will provide flow control mitigation for approximately 5.7 acres of effective 38 impervious area. After flow control BMPs (as feasible and applicable) are implemented on a 39 proposed development site within the Johns Creek Basin, any additional required flow 40 control mitigation maybe fulfilled off-site by the City's sub-regional facility and Green 41 Connections. To do so, project applicants will need to demonstrate that the net effective 42 impervious area for the development or redevelopment site, constructed public 43 infrastructure improvements and post-2011 projects for the entire Sunset area is less than or 10 SUNSETAREA_SURFACEWATER_MASTERPLAN_0421_COUNCILREVIEWDRAFT.DOCX ORDINANCE NO. 5611 3 APPLICABLE REGULATIONS 1 equal to the current (2011) existing conditions. Flow control mitigation for all targeted 2 surfaces will be required to be met on-site under the following conditions: 3 • Proposed projects precede construction of the public infrastructure improvements 4 • Connection to the downstream drainage system is not available. 5 • Net new effective impervious area of the proposed project plus projects constructed 6 in the Study area after 2011 (after implementing Flow Control BMPs) exceeds 5.7 7 acres (or the total area mitigated by the constructed public infrastructure projects) 8 • Or a combination of the three conditions above. 9 No pubhc infrastructure projects are proposed within the May Creek Basin and therefore 10 individual development or redevelopment projects will be required to comply with the 11 appropriate flow control requirements on-site. SUNSETAREA_SURFACEWATER_MASTERPLAN_0421_COUNCILREVIEWDRAFT.DOCX 11 ORDINANCE NO. 5611 i 4 Proposed Projects 2 As part of the Planned Action Draft EIS (City of Renton 2010b) and the Sunset Community 3 Investment Strategy (City of Renton 2009), several stormwater projects were identified, 4 including a sub-regional flow control facility, Green Connections using low-impact 5 development facilities (LID), a new conveyance system, and upsizing of the existing system. 6 These projects will provide flow control, water quality improvements, or conveyance 7 capacity for future redevelopment. 8 Green Connections 9 Green Connections involves street improvements meeting the City of Renton Complete 10 Street requirements. Complete Streets include features that enhance the pedestrian 11 experience such as wider sidewalks, narrower travel lanes for vehicles, and landscaping in 12 the form of rain garden/planters. Harrington Avenue NE, Jefferson Avenue NE, Edmonds 13 Avenue NE, 12th Street, and two alleys were identified as potential locations for Green 14 Connection improvements. Ten segments of Green Connections improvements were 15 identified for potential implementation. Three segments are located on Harrington Avenue 16 NE. Another three segments are located on NE 12th Street and Edmonds Avenue NE. One 17 segment is on Jefferson Avenue NE. Two segments are on alleys: one is west of Jefferson 18 Avenue NE, and the other one is west of Harrington Avenue NE. A last segment is on the 19 sidewalk between NE 16th Street and Index Avenue. Figure 4 shows the location of the 20 Green Connection projects. 21 The primary storm drainage features of the Green Connections projects consist of roadside 22 rain gardens and permeable sidewalks. Roadside rain gardens receive stormwater runoff 23 from the roadway and, in limited instances, from adjacent properties. The runoff is treated 24 by flowing through tire bioretention soil mix (consisting of sandy loam soils and compost) 25 and vegetation, and then infiltrated into the native ground during smaller storms. During 26 larger or higher-intensity storms, the stormwater runoff will continue to infiltrate as allowed 27 by the native soil, with excess runoff stored temporarily in the soil and the active storage 28 within the rain garden. Once the storage and infiltration capacity of the rain garden is 29 exceeded, runoff would then overflow into the street. Where native soil infiltration capacity 30 is limited, the rain gardens would be installed with subsurface underdrains to collect the 31 treated water that filters through the bioretention soils. A storm drain system will be needed 32 to convey the overflow runoff from the rain garden and to meet the City's storm drain 33 design standard. Only the cost of the Low Impact Development improvements (e.g. rain 34 gardens, porous sidewalks, etc.) associated with the green connections are shown in Table 2. 35 The storm drain conveyance systems needed for street improvements are includes as part of 36 the street improvements cost estimates included in the capital facilities plan. 37 Residential Access Streets 38 Harrington Avenue, Jefferson Avenue, NE 16th Street, and NE 9th Street are classified as 39 Residential Access Streets in the City of Renton Compete Street Ordinance (5517). Per this SUNSETAREA_SURFACEWATER_MASTERPLAN_0421_COUNCILREVIEWDRAFT.DOCX 13 4 PROPOSED PROJECTS ORDINANCE NO. 5611 Ordinance residential access streets requires a right-of-way width of 53 feet for a two-lane road. This breaks down into 20 feet of paved roadway, 6 feet of parking on one side of the street, a 6-foot-wide sidewalk, and an 8-foot planter strip on both sides of the street. 14 SUNSETAREA_SURFACEWATER_MASTERPLAN_0421_COUNCILREVIEWDRAFT.DOCX g Regional Stormwater Facility Planned Action Study Area P [ZD Parcels Rj Green Connections I Alley Woonerf reen Access 1W Green Collector Arterial Permeable Sidewalk Drainage Facility Sub-Basins HSi Honey Creek ELJJJ Johns Creek I I Johns Creek - Sunset Terrace I ! May Creek N A 0 600 1,200 Feet nrm ORDINANCE NO. 5611 CH2IVIHILL Figure 4 Green Connections City of Renton Sunset Area Master Drainage Plan ORDINANCE NO. 5611 4 PROPOSED PROJECTS 1 The existing right-of-way on these streets is 60 feet; thus there is an additional 7 feet of space 2 that can be used for low-impact development features. The proposed Green Connection 3 typical street section would include 20 feet of paved roadway with 6 feet of parking on one 4 side of the street, an 8-foot sidewalk on one side of the street and a 5-foot sidewalk on the 5 other side of the street, and a 6-foot planter and a 12-foot rain garden on one side of the 6 street. It requires a total of 58 feet of street width. Figure 5 shows the proposed roadway 7 section. 8 Harrington Avenue NE 9 Three segments of Green Connections are proposed in Harrington Avenue Ne. The northern 10 segment on Harrington Avenue NE is between NE 16th Street and NE 12th Street. This 11 Green Connection corridor would be enhanced by narrowing the through-traffic lanes to 12 calm traffic, creating wide planter areas and wider sidewalks as shown in the City's 13 complete street section. The 2 10 feet of vehicle travel lanes will be centered on the street 14 right-of-way. A rain garden (12 feet wide) and the 6-foot parking with 6-foot-wide planter 15 will be generally alternating on either side of the street. An 8-foot-wide sidewalk will be on 16 the west side of Harrington adjacent to the McKnight Middle School and a 5-foot sidewalk 17 on the east. At the end of the block, rain gardens will be on both sides of the street. 18 Depending on the need for street parking, parking may be available on both sides of the 19 street at selected locations. 20 The middle segment is between NE 12th Street and Sunset Boulevard. A portion of 21 Harrington Avenue NE will be vacated, becoming an open space for Sunset Terrace, and 22 there will be no Green Connection in this portion. The last segment is the south segment, 23 between Sunset Boulevard and NE 8th Place, and on NE 9th Street between Harrington 24 Avenue NE and Index Avenue NE. The street improvements for the middle and south 25 segments would be similar to the north segment. 26 Jefferson Avenue 27 Jefferson Avenue NE is a residential access street, like Harrington Avenue NE. The typical 28 2-lane street section used on Harrington Avenue NE will be used on Jefferson Avenue NE as 29 well. It will have two 10-foot travel lanes in the center, with the rain gardens either on 30 alternating sides or both sides of the street. 31 Collector Arterials 32 NE 12th Street and Edmonds Avenue NE is classified as collector arterial in the City of 33 Renton Complete Street Ordinance. The required width for a collector arterial includes a 83- 34 foot right-of-way for a two-lane road and 94foot right-of-way for a three-lane road. The 35 street section generally requires 30 feet of paved roadway for vehicle and bicycle lanes, 8 36 feet of parking, and 8-foot sidewalks and 8-foot planter stiips on both sides of the street. The 37 proposed typical street section for this Green Connection would include a minimum of 30 38 feet for paved roadway, 8 feet of parking, an 8-foot planter strip on one side of the street, a 39 16-foot rain garden on the other side of the street, and 8-foot-wide sidewalks on both sides 40 of the street. Figure 6 shows the proposed two-lane, three-lane, and four-lane roadway 41 sections. 42 16 SUNSETAREA_SURFACEWATER_UASTERPLAN_0421_COUNCILREVIEWDRAFT.DOCX ORDINANCE NO. 5611 Section 1: Rain Garden on West Side of Street AKPftU&MAlE EXISTING RlC3H)-0i--WAr * 1r——^ 6> * 5' k * '"P *- W PARKING PLANTER; SIDEWALK SIDEWALK RAINUGARPEW 58'Proposed Road Section Section 2: Rain Garden on Both Sides APPROXIMATED EXISTING MGHT-OF-WAY 10' SIDEWALK RAIN-GARDEN RAM-GARDEN: 58* Proposed Road Section! : Figure 5 Harrington and Jefferson Avenue Sections ORDINANCE NO. 5611 Section 1: Collector Arterial with Left Turn Lane (Edmonds Ave.) Section 2: Collector Arterial, 2-Lane with Shared Roadway (12th St & Edmonds Ave.) 83' REQUIRED RIGHT-OF-WAY | \< — _ • —— 78' PROPOSED ROAD SECTION ; f I RAIN GARDEN AND PARKING.'PLANTER SECTION, ALTERNATE STREET SIDES Section 3: 4-Lane Collector Arterial, No Parking (12th Street) 82' PROPOSED ROAD SECTION _ : """"""" ' M-.....U,, „.,„l„„,l, l> I Figure 6 Edmonds and 12th Street Sections ORDINANCE NO. 5611 4 PROPOSED PROJECTS 1 The Green Connection on collector arterial includes Edmonds Avenue from 7th Avenue to 2 NE 12th Street, then continues eastward on NE 12th Street to Monroe Avenue NE. Three 3 typical sections are proposed for these two collector arterials. These sections are shown in 4 Figure 6. 5 Other Green Connection Improvements 6 Green alleys are proposed in two locations. One is on the parcel between Jefferson Avenue 7 and Index Avenue, north of NE 12th Street, and the other is in the alley between Harrington 8 Avenue and Glennwood Avenue, south of Sunset Boulevard. Green alleys consist of a 9 narrow conventional asphalt driving aisle with adjacent permeable pavement shoulders for 10 delmeating areas for pedestrians and infiltrating stormwater. 11 Pervious sidewalk is proposed between Index Avenue and NE 16th Street, coimecting the 12 Index Avenue neighborhood to the Hillcrest neighborhood. 13 Sunset Terrace Sub-Regional Facility 14 Sunset Terrace is located between Sunset Boulevard (SR 900), Edmonds Ave, and NE 12th 15 Street. It is currently a multi-family and retail commercial use area. Under the Preferred 16 Alternative in the Planned Action Final Environmental Impact Statement, the Sunset Terrace 17 public housing community would be redeveloped into a mixed-use, mixed-income 18 residential and commercial space with public amenities. An open space/park would be 19 centered in this redevelopment, which has been identified as a potential location for a sub- 20 regional stormwater facility. To maximize the open space area, most of this sub-regional 21 facility will be underground. It is proposed to be located at the northwest corner of the open 22 space, which allows pubhc usage of most of the park space and allows maintenance access 23 from NE 10th Street. 24 The Sunset Community Investment Strategy identified three additional potential locations 25 for sub-regional stormwater facilities in the John's Creek Basin: at Hillcrest Terrace, on a 26 vacant lot north of Sunset Park, and in Highland Park. Through analysis of the potential 27 land use changes and redevelopment under the Preferred Alternative of the Planned Action 28 Final EIS, it was determined that up to 2.6 acres of the 5.7 acres of additional effective 29 impervious surface area could be created at full build-out conditions. It was determined that 30 a single facility could meet the flow control needs of this new impervious area. The 31 construction of the sub-regional facility can be part of the redevelopment and optimize the 32 construction cost. This facility can provide flow control protection and water quality 33 treatment in the basin in advance of the rest of the redevelopment. 34 A sub-regional facility will provide stormwater infiltration as practical to control the runoff 35 volume and reduce potential pollutants. Pre-treatment will be provided prior to infiltration 36 via rain gardens. Stormwater runoff volume that cannot be infiltrated will be detained in an 37 underground vault and will be released matching existing flow conditions. 38 Soil 39 The soil at the proposed sub-regional facility site is at the boundary of glacial till and 40 advance outwash soil. Further soil exploration is needed for the final design of the facility to SUNSETAREA_SURFACEWATER_UASTERPLAN_0421_COUNCILREVIEWDRAFT.DOCX 19 ORDINANCE NO. 5611 4 PROPOSED PROJECTS 1 determine the soil properties onsite. The sub-regional facility will be sized using low 2 infiltration rates typical of till soil conditions. 3 Tributary and Land Cover 4 The tributary area draining to this facility could be from Sunset Terrace, Sunset Boulevard 5 from 10th Street to Monroe Avenue, Glennwood Avenue, and Sunset Lane or some private 6 parcels along Sunset Lane. To maximize the water quality treatment benefit of pretieatment 7 and infiltration, it is preferable to convey stormwater runoff from public roadways (e.g., 8 Sunset Boulevard), which has the highest pollutant loading. The actual confributing area 9 will be determined based on the redevelopment of NE 10th Street and Sunset Boulevard in 10 the future. 11 Facility Design 12 The facility is prehminarily sized to provide flow control for the expected 2.6 acres of 13 increase in impervious surface area related to the redevelopment. Table 1 summarizes the 14 targeted design level for flow control for the subregional facility and Green Connections 15 projects. The stormwater runoff from Sunset Boulevard will drain to NE 10th Street, then 16 flow to a series of rain gardens with a total bottom area of 3,100 square feet on the north side 17 of the proposed Sunset Terrace Park. The rain gardens would provide pretieatment for the 18 water flowing through the bioretention soil and vegetation. Perforated drains pipes beneath 19 the rain garden would collect treated runoff and distribute the water to an infiltration 20 gallery south of the rain garden. It would have a bottom area of 12,500 square feet to 21 increase the available area for infiltration into the native soil. Flows that exceed the 22 infiltration capacity of the rain garden and infiltration gallery would overflow into a 23 conventional storm drain system, and into an underground detention vault west of the 24 infiltration gallery. The detention vault is prehminarily sized to have an active storage 25 volume of 0.38 acre-feet. The vault would control the release rate of the water, matching the 26 peak flow rate for the existing conditions. Figure 7 shows the conceptual layout of the sub- 27 regional facility and Appendix A shows the summary of analysis of the expected new 28 effective impervious area. Appendix Dl summarizes the preliminary sizing calculations 29 using the Western Washington Hydrology Model (WWHM v. 3.0). 30 Upon further investigation of the native soil infiltration capacity, design modifications could 31 include either increasing the size of the detention vault and eliminating the infiltration 32 gallery (if infiltration is largely infeasible) or decreasing the size of the detention vault (if the 33 infiltration rate is greater than the preliminary sizing assumption of 0.25 inch/hour). 34 The intent of the subsurface infiltration gallery is to preserve open space for active space 35 and recreation. The rain garden is proposed to be located in the northwest corner of the 36 open space to provide a landscaped buffer between the open space and the street. Figure 7 37 shows the conceptual layout of the facility. The stormwater runoff could be conveyed from 38 storm drains on Sunset Lane or S 10th Street. The discharge from the detention vault will 39 connect to an existing storm dram on Sunset Boulevard at Harrington Avenue S by a new 40 storm drain under the vacated Harrington Avenue. 41 20 SUNSETAREA_SURFACEWATER_MASTERPLAN_0421_COUNCILREVIEWDRAFT.DOCX ORDINANCE NO. 5611 PROPOSED PROJECTS TABLE 1 Targeted Level of Flow Control Mitigation by Public Infrastructure Projects Title Targeted Flow Reduction of Flow Control BMPs or Facility Net Effective Impervious Area Reduction (ac) 1 Sunset Terrace Regional Facility 100% 2.6 2 Harrington Avenue NE Green Connection 30% 0.6 3 Jefferson Avenue NE Green Connection 30% 0.5 4 Alley Green Connections (Harrington, Jefferson Alleys) 50% 0.5 5 Collector Arterial Green Connection (Edmonds Avenue NE and NE 12th Street) Total 20% 1.5 5.7 Note: Net effective impervious area reduction includes new/reduced impervious area to construct proposed section (e.g., new sidewalks) and effective performance of flow control BMPs within the Green Connection project. 1 2 Conveyance Improvements 3 The future development is expected to mcrease effective impervious surface area. A 4 schematic storm drain network model was developed to estimate the design peak flow for 5 planning purposes. This model uses Santa Barbara Unit Hydrograph methodology with 6 Type 1A storm rainfall distribution using StormShed2G computing software. Seven 7 conveyance system improvements are proposed. The conveyance improvements are shown 8 in Figure 8 and are classified based on the condition of the existing storm drain system and 9 the concurrence with other transportation improvements below. The peak flow rate 10 summary of the sub-tributary area is included in Appendix B. Conveyance capacity 11 calculations using SBUH methodology in the StormShed™ hydraulic model are provided 12 in Appendix D2. 13 New Storm Drains with Green Connections 14 Harrington Avenue NE and Jefferson Avenue NE currently do not have a storm drain 15 system. With the street unprovements for the proposed Green Comrections, a new storm 16 drain will be required. The conveyance system improvements in Harrington Avenue NE are 17 separated to match the same segments for the Green Connection street improvements. It is 18 assumed that the storm drain conveyance improvements needed with the street 19 improvements would occur concurrently with the proposed Green Connections 20 improvements to decrease costs. SUNSETAREA_SURFACEWATER_MASTERPLAN_0421_COUNCILREVIEWDRAFT.DOCX 21 ORDINANCE NO. 5611 W CH2MH1LL Figure 7 Sub-Regional Flow Control Facility City of Renton Sunset Area Master Drainage Plan ORDINANCE NO. 5611 tZjSunset Study Area ! i Renton Parcels Stormwater Conveyance System Proposed New Storm Drain -=m Proposed to Replace — Proposed to Abandon Existing Storm Drain N A 0 600 IrJhUbiH NOTES: 1 FLOWS INDICATED ARE FOR THE 25-YEAR DESIGN EVENT ONLY. 2 PIPE DIAMETERS SHOWN INDICATED REQUIRED SIZE UNDER PROPOSED CONDITIONS. _ CH2MHILL Figure 8 STORMWATER DRAINAGE CONVEYANCE SYSTEM City of Renton Sunset Area Master Drainage Plan ORDINANCE NO. 5611 4 PROPOSED PROJECTS 1 Replace Storm Drains with Green Connections 2 The Edmonds Avenue NE and NE 12th Street storm drain systems are undersized for both 3 existing and future redevelopment conditions. The proposed conveyance system 4 improvements are separated to match the segments for Green Connections. It is assumed 5 that these storm drain conveyance improvements needed for the street improvements 6 would occur concurrently with the proposed the Green Connections improvements to 7 decrease costs. 8 Replace Existing Storm Drain without Street Improvement 9 The existing storm drain system of Kirkland Avenue NE is undersized for existing and 10 future development conditions. No Green Connections or street improvements are 11 proposed for Kirkland Avenue NE, and therefore these improvements are assumed to occur 12 independently. 13 New Storm Drain without Street Improvement 14 Glennwood Avenue NE currently has no conveyance system and will require a new storm 15 drain system to serve as a connection for future redeveloped properties. No Green 16 Connections or street improvements are proposed for Glenwood Avenue NE, and therefore 17 these improvements are assumed to occur independently. 18 Replace Existing Storm Drain with Street Improvement 19 Sunset Boulevard is a major east-west arterial connecting the Sunset Terrace neighborhood, 20 the Renton Highland area, and Interstate 1-405. As part of redevelopment plan for Sunset 21 Terrace, improvements on Sunset Boulevard are proposed to provide the Complete Street 22 section requirements, including bicycle lanes, planter strips, and sidewalks. 23 The current GIS map shows that a portion of the eastbound Sunset Boulevard storm drain 24 system will leave the street right-of-way and go underneath several private properties near 25 NE 9th Street and Ferndale Circle NE. Then this system will continue west under NE 9th 26 Place down to the valley. With the improvements on Sunset Boulevard, it is preferable to 27 reroute these conveyance system back and remain along the Sunset Boulevard. A field 28 investigation is needed to confirm the location and routing of this storm drain. Further 29 analysis is needed to verify the capacity of the storm drain downstream of the study area. 30 City of Renton staff has indicated that the storm drain system at NE 9th Place may have 31 capacity issues further downstream. Further engineering analysis is needed to determine 32 whether to continue to route the stormwater runoff from Sunset Boulevard to this storm 33 drain system. 24 SUNSETAREA_SURFACEWATER_MASTERPLAN_0421_COUNCILREVIEWDRAFT.DOCX ORDINANCE NO. 5611 i 5 Project Implementation 2 Consistent with existing and proposed goals and pohcies, two priority levels for surface 3 water improvements have been identified in order to prioritize projects presented in this 4 plan. Conceptual project solutions were developed for other problems based on the Sunset 5 Community Investment Strategy (City of Renton 2009) and other information provided by 6 the City. The development of a conceptual project solution began with a review of the study 7 area to determine if property is available for a detention facility and the need to upsize the 8 existing pipe systems or the need to add a new pipe system where there is no existing 9 system. Pipe capacity was analyzed with a schematic hydrological and hydraulic model 10 using Santa Barber Unit Hydrograph method and hydraulic grade line analysis. 11 Project implementation requires future engineering analysis, soil exploration, and 12 engineering design to confirm all assumptions and design information. For the conveyance 13 system, the design will provide protection at the level of a 25-year storm. The flow control 14 facilities will maximize infiltration where feasible and control release rates to match the 2-, 15 10-, and 100-year runoff rates for existing pre-development conditions. 16 Table 2 and Table 3 show the projects that are categorized for priority level 1 and level 2. 17 The implementation of each project depends on the availability of City funding, the possible 18 developer contribution, and the pace and scale of redevelopment happening in this area in 19 the future. TABLE 2 Priority Level 1 Projects and Costs Title Description Opinion of Cost 1 Sunset Terrace Regional Facility Sunset Terrace Regional Facilities including bioretention swale, infiltration gallery, and detention vault $722,700.00 2aa Harrington Avenue NE Green Connection - Segment 1 Segment 1 from16th Street to 12th Street. Construct rain gardens on the sides of the street. $602,250.00 2ba Harrington Avenue NE Green Connection - Segment 2 Segment 2 from NE 12th Street to NE 10th Street. Construct rain gardens on the sides of the street. $328,500.00 2ca Harrington Avenue NE Green Connection - Segment 3 Segment 3 from Sunset Blvd. to NE 9th Street. Construct rain garden on the sides of the street. $459,900.00 Total $2,113,350.00 Note: The cost represents the construction cost in March 2011 dollars. a Cost only includes the low impact development features; the storm drain conveyance cost is part of the street improvements. SUNSETAREA_SURFACEWATER_MASTERPLAN_0421_COUNCILREVIEWDRAFT.DOCX 25 5 PROJECT IMPLEMENTATION ORDINANCE NO. 5611 TABLE 3 Priority Level 2 Projects and Costs Title Description Opinion of Cost 3 Glennwood Avenue NE Storm Drainage Conveyance Improvements Construct new storm drainage pipes. $328,500.00 4a NE 12th Street Green Connection From Jefferson Avenue NE to Edmunds Avenue NE. Construct rain garden on the sides of the street. $646,050.00 5aa Edmunds Avenue NE Green Connection From NE 12th Street to NE 10th Place. Construct rain garden on the sides of the Street. $372,300.00 5ba Edmunds Avenue NE Green Connection From NE 10th Place to NE 6th Place. Construct rain garden on the sides of the Street. $755,550.00 6 Kirkland Avenue NE Storm Drainage Conveyance Improvements Upsize existing storm drainage pipes $602,250.00 7 Jefferson Avenue NE Green Connection From NE 16th Street to NE 12th Street. Construct rain garden on the sides of the Street. $328,250.00 Total $3,032,900.00 Note: The cost represents the construction cost in March 2011 dollars. a Cost only include the low impact development features; the storm drain conveyance cost is part of the street improvements. 1 Project Planning Cost Estimate 2 A conceptual estimate of construction cost has been prepared for these new projects. These 3 costs are shown in Table 1 for Priority Level land Table 2 for Priority Level 2. The cost tables 4 in this chapter present the construction cost estimates in March 2011 dollars. The cost for the 5 Green Connection is only included the LID features. The cost for the conveyance system is 6 part of the roadway improvement cost, when one is proposed. However, if street 7 improvements are not proposed, the new or replaced conveyance cost would be included in 8 the estimates. The cost estimates do not include design engineering and construction plans 9 development, the purchase of right-of-way or construction easement, City administration, 10 and construction management. The breakdown of the summary of cost is included in 11 Appendix C. 12 These improvements would be needed witiiin the 2011-2030 time frame. The project costs 13 and funding sources for these projects are identified in the Sunset Area Community Capital 14 Facilities Plan found within the City's Capital Facilities ElementFunding for the surface 15 water master plan improvements will come through a variety of sources and means. Public 16 funding will be sought through grant programs, dedication of funds through City Council 17 or partial funding through available utility fees. Where pubhc firnding cannot be secured, 18 the remaining funding will be provided by future development through a combination of 26 SUNSETAREA_SURFACEWATER_MASTERPLAN_0421_COUNCILREVIEWDRAR.DOCX ORDINANCE NO. 5611 5 PROJECT IMPLEMENTATION frontage improvements and fee assessments under various structures depending on applicable city codes, implementation schedule and rate of redevelopment such as collection of impact fees, fee in lieu of mitigation and special assessment districts. SUNSETAREA SURFACEWATER_MASTERPLAN_0421_COUNCILREVIEWDRAFT.DOCX 27 ORDINANCE NO. 5611 1 6 References 2 City of Renton. 2010a. Amendments to King County Surface Water Design Manual. Available at: 3 http://rentonwa.gov/uploadedFiles/Government/PW/UTILITIES/5urface Water/City% 4 20Amendments%20to%20^e%20 5 ual.pdf. February 2010. 6 City of Renton. 2010b. Draft Sunset Area Community Planned Action NEPA/SEPA 7 Environmental Impact Statement. Prepared for City of Renton and Renton Housing Authority. 8 Available at: 9 http: / / renton wa. gov / uploadedFiles / Business / CED / planning/ 2010 / Voll SunsetArea- 10 PA DraftEIS.pdf. December 2010. 11 City of Renton. 2009. Sunset Community Investment Strategy. Available at: 12 http: / / rentonwa. gov/ uploadedFiles / Business / EDNSP / plarming/ 091123-SunsetCIG- 13 FinalReport-Adopted-lowres.pdf. Adopted November 23, 2009. 14 City of Renton and King County. 2001. May Creek Basin Action Plan. April 2001. 15 Foster Wheeler Environmental Corporation. 1995. May Creek Current and Future Conditions 16 Report. August. Washington State Department of Ecology. 2009. 17 King County. 2009. King County, Washington, Surface Water Design Manual. King County 18 Department of Natural Resources and Parks. Available at: 19 http: / /your.kingcounty.gov/dnrp/library/water-and-land/stormwater/surface-water- 20 design-manual/SWDM-2009.pdf. January 9,2009. 21 Washington Department of Ecology. 2005. Stormwater Management Manual for Western 22 Washington. Available at: 23 http:/ /www.ecy.wa.gov/programs/wq/stormwater/manual.html. April 2005. SUNSETAREA_SURFACEWATER_MASTERPLAN_0421_COUNCILREVIEWDRAFT.DOCX 29 ORDINANCE NO. 5611 Appendix A - Summary of Expected New Effective Impervious Surface Area ORDINANCE NO. 5611 Table A-l. Existing Land Cover Summary Total Area (acres) Total Impervious Area (acres) Total Pervious Area (acres) Total PGIS3 (acres) Total Untreated PGIS3 (acres) Effective Impervious Planned Action Study Area 255.82 161.17 94.65 92.86 88.10 161.17 Potential Sunset Terrace Redevelopment Subareah 12.64 4.73 7.91 1.83 1.83 4.73 Total 268.46 165.90 102.56 94.69 89.93 165.90 aPGIS = pollution-generating impervious area bThe Sunset Terrace Redevelopment Subarea is slightly smaller than the subarea in the DEIS due to the adjusted boundary at Sunset Boulevard and Harrington Ave. Table A-2. Land Cover Summary—Preferred Alternative Total Area (acres) Total Impervious Area (acres) Total Pervious Area (acres) Total PGIS (acres) Total Untreated PGIS (acres) Effective Impervious (acres) Planned Action Study Area 255.82 174.40 81.42 76.44 46.26 165.41 Potential Sunset Terrace Redevelopment Subarea3 12.64 6.1 6.54 1.7 0 3.66 Total 268.46 180.50 87.96 78.14 46.26 169.07 Table A-3. Change in Land Cover Summary—Preferred Alternative Project Area Net Change in Impervious Area (acres) Net Change in PGIS Area (acres) Net Change in Untreated PGIS (acres) Net Change in Effective Impervious Area (acres)3 Planned Action Study Area Potential Sunset Terrace Redevelopment Subarea 13.23(8.2%) -16.41 (-17.7%) -41.84 (-47.5%) 4.24 (2.6%)b 1.37 (29.0%) -0.13 (-7.1%) -1.83 (-100%) -1.07 (-22.6%)h Total 14.60 (16.2%) -16.54 (-18.4%) -43.67 (-48.6%) 3.17 (1.9%) Note: All areas are expressed relative to existing conditions. See Section 3.3 of the Draft Environmental Impact Statement (Table 3.3-1) for a summary of existing conditions. 3 Impervious area not directly connected to a stream or drainage system. b The net change in effective impervious area within the Johns Creek Basin, excluding mitigation through regional detention, is equal to 2.63 acres. Within the May Creek Basin, the net change is equal to 0.54 acre. ORDINANCE NO. 5611 Appendix B - Summary of Peak Flow Rates for the Study Area ORDINANCE NO. 5611 Table B-1. The Existing Conditions Area Breakdown for the Sub-Tributary Area Sub- Basin Area Existing Condition Total Area Sub- Basin Area Impervious Pervious Lawn Forest Total Area Sub- Basin Area Road Roof (outwash) Roof (till) Total Impervious Outwash Till Forest Total Area Sub- Basin Area (ac) (ac) (ac) (ac) (ac) (ac) (ac) (ac) 1 6.4 7.31 16.95 30.66 6.63 6.39 0.80 44.48 2 5.5 2.46 -7.96 1.96 --9.92 3 1.91 0.34 0.65 2.90 6.51 12.31 -21.72 4 4.92 2.12 4.25 11.29 2.88 4.25 -18.42 5 0.92 0 1.71 2.63 5.41 1.25 -9.29 6 3.77 0 11.67 15.44 -4.46 -19.90 7 2.47 0 9.22 11.69 -5.21 -16.90 9 8.79 0 17.88 26.67 0.02 6.03 -32.72 10 1.39 14.58 14.04 30.01 19.77 2.91 -52.69 11 5.58 4.78 0.92 11.28 1.37 0.55 -13.20 12 2.15 10.83 0.39 13.37 4.66 --18.03 13 12.30 -4.3 16.60 16.60 Total 56.10 42.42 81.98 180.50 49.21 43.34 0.80 273.85 a. The roof runoff is modeled as hydrological soil group B grass to estimate potential low range under existing conditions reflecting potential rooftop disconnection. ORDINANCE NO. 5611 Table B-2. The Proposed Conditions Area Breakdown for the Sub-Tributary Area Sub- Basin Area Preferred Proposed Condition Total Area Sub- Basin Area Impervious Pervious Lawn Forest Total Area Sub- Basin Area Road Roof (outwash) Roof (till) Total Impervious HSGB HSGC Forest Total Area Sub- Basin Area (ac) (ac) (ac) (ac) (ac) (ac) (ac) (ac) 1 6.40 7.85 17.36 31.61 6.09 5.98 0.80 44.48 2 5.50 2.74 -8.24 1.67 --9.91 3 1.91 0.34 0.65 2.90 6.51 12.305 -21.72 4 4.92 2.86 5.1 12.88 2.14 3.4 -18.42 5 0.92 3.55 2.37 6.84 1.86 0.59 -9.29 6 3.77 0.00 13.9 17.67 -2.23 -19.90 7 2.47 0.00 9.45 11.92 -4.98 -16.90 9 8.79 0.00 18.24 27.03 0.02 5.67 -32.72 10.0 1.39 15.4 13.7 30.4 18.99 3.26 -52.69 11 5.58 5.52 1.31 12.41 0.63 0.16 -13.20 12 2.14 13.17 0.37 15.68 2.32 0.03 -18.03 13 12.30 -4.3 16.60 16.60 Total 56.09 51.39 86.74 194.22 40.23 38.60 0.80 273.85 ORDINANCE NO. 5611 I Drainage Areas |^Js unset Study Area I I Developed ' " Excluded D Redevelopable CJ Vacant ESI Roads & Basins Outside Project Boundary E3cv E33R-10 lR-14 f R-8 IRM-F I I Renton Parcels N 4 I I iource: AK( - j~T_l M—!. nki H •"Ti ; ; t HILL Figure 01 STORMWATER DRAINAGE BASINS City of Renton Sunset Area Master Drainage Plan ORDINANCE NO. 5611 The stormwater runoff peak flow rate is calculated using Santa Barbara Unit Hydrograph (SBUH) (TR55) methodology and it was computed by the Stormshed2G program. Table B-3. Existing Conditions Stormwater Runoff Peak Flow Rate Sub- Basin Area Stormwater Runoff Peak Flow Rate Sub- Basin Area Design Event (SBUH) Sub- Basin Area 2-year 10-year 25-year 100-year 1 8.4 14.7 18.1 21.5 2 2.3 4.0 4.9 5.9 3 2.2 4.9 6.4 7.9 4 3.1 5.5 6.8 8.1 5 1.5 3.1 3.9 4.8 6 4.4 7.1 8.5 9.9 7 4.2 6.9 8.3 9.7 9 9.5 15.2 18.1 21.0 10 14.0 24.2 29.6 35.1 11 2.4 4.3 5.3 6.4 12 4.1 6.7 8.1 9.4 13 6.0 9.3 10.9 12.5 Table B-4. Proposed Conditions Stormwater Runoff Peak Flow Rate Sub- Basin Area Stormwater Runoff Peak Flow Rate Sub- Basin Area Design Event (SBUH) Sub- Basin Area 2-year 10-year 25-year 100-year 1 10.4 17.2 20.7 24.2 2 3.2 5.1 6.0 7.0 3 2.3 5.0 6.5 8.0 4 3.8 6.4 7.7 9.0 5 2.8 4.6 5.6 6.5 6 4.8 7.5 8.9 10.3 7 4.2 6.9 8.3 9.7 9 9.6 15.3 18.2 21.1 10 14.2 24.4 29.9 35.4 11 3.9 6.1 7.2 8.3 12 4.7 7.4 8.8 10.2 13 6.0 9.3 10.9 12.5 ORDINANCE NO. 5611 Appendix C - Opinion of Cost ORDINANCE NO. 5611 RENTON SUNSET PLAN ACTION EIS PROJECT DATE: 3/9/2011 REGIONAL FACILITIES PROJECT NO.: 408314 ORDER OF MAGNITUDE ESTIMATE TOTAL UNIT TOTAL DESCRIPTION QTY UNIT COST COST Bioretention Swale (vegetated) Excavation & Waste 1,421 CY $20.00 $28,420 Compost 350 CY $30.00 $10,500 Seeding 654 SY $3.76 $2,458 Misc. Detail Allowance 1 LS $4,137.80 $4,138 Bioretention Swale Subtotal $45,516 Infiltration Gallery Excavation 3,100 CY $10.00 $31,000 Waste 694 CY $10.00 $6,940 Native Backfill 2,406 CY $15.00 $36,090 Drain Rock 694 CY $30.00 $20,820 Seeding 1,390 SY $3.76 $5,221 Geotextile (wrap around drain rockx2) 2,780 SY $2.00 $5,560 6" Perforated Pipe, A' O.C (32 ea at 100') 3,200 LF $3.00 $9,600 Cleanout (32 ea, per 6" pipe) 32 EA $200.00 $6,400 Birdcage Overflow Structure (CB Type 2) 1 EA $1,000.00 $1,000 Misc. Detail Allowance 1 LS $12,263.07 $12,263 Infiltration Vault Subtotal $134,894 Detention Vault Detention Vault (135'x20,x7.5') 1 EA $180,000.00 $180,000 Excavation 1,775 CY $10.00 $17,750 Waste (Vault Size, 135'x20'x7.5') 750 CY $10.00 $7,500 Native Backfill 1,025 CY $15.00 $15,375 Seeding 690 CY $3.76 $2,592 CSBC (6" layer) 74 CY $35.00 $2,590 Detention Vault ManHole Access 3 EA $1,000.00 $3,000 Flow Control Structure, at south end of Det. Vault 1 EA $3,000.00 $3,000 12" CPEP Storm Drain 420 LF $49.69 $20,868 Manhole 1 EA $2,000.00 $2,000 Manhole (Tie into Existing SD) 1 EA $2,500.00 $2,500 Misc. Detail Allowance 1 LS $25,717.45 $25,717 Detention Vault Subtotal $282,892 SUBTOTAL $463,302 MOBILIZATION, BONDS, INSURANCE, TEMP. FACILITIES, DEMOB, ETC 10.0% $46,330 SUBTOTAL $509,632 CONTINGENCY 30.0% $152,890 CONSTRUCTION TOTAL (ROUNDED) $660,000 SALES TAX 9.5% $62,700 CONSTRUCTION TOTAL (ROUNDED) $722,700 Low range -30.0% $510,000 High Range 50.0% $1,080,000 NOTE: The above cost opinion is in March 2011 dollars and does not include future escalation, financial or O&M costs. The cost opinion shown has been prepared for guidance in project evaluation from the information available at the time of preparation. The final costs of the project will depend on actual labor and material costs, actual site conditions, productivity, competitive market conditions, final project scope, final schedule and other variable factors. As a result, the final project costs will vary from those presented above. Because of these factors, funding needs must be carefully reviewed prior to making specific financial decisions or establishing final budgets. project scope, final schedule and other variable factors. As a result, the final project costs will vary from those presented above. Because of these factors, funding needs must be carefully reviewed prior to making specific financial decisions or establishing final budgets. ORDINANCE NO. 5611 RENTON SUNSET PLAN ACTION EIS PROJECT HARRINGTON AVE GREEN CONNECTION ORDER OF MAGNITUDE ESTIMATE DATE: PROJECT NO.: 3/9/2011 408314 TOTAL UNIT TOTAL DESCRIPTION : ••• ' QTY UNIT COST COST HARRINGTON GREEN CONNECTION TOTAL LENGTH 1,791 LF From 16th Street to 12th Street Section 1: Rain Garden on West Side of Harrington 1,279 LF 12-ft Rain Garden Strip 15,348 SF $18.86 $289,446 Section 1 Subtotal $289,446 Section 2: Rain Garden Both Sides 205 LF 12-ft Rain Garden Strip (x2) 4,920 SF $18.86 $92,786 Section 2 Subtotal $92,786 SUBTOTAL $382,231 MOBILIZATION, BONDS, INSURANCE, TEMP. FACILITIES, DEMOB, ETC 10.0% $38,223 SUBTOTAL $420,454 CONTINGENCY 30.0% $126,136 CONSTRUCTION TOTAL (ROUNDED) $550,000 SALES TAX 9.5% $52,250 CONSTRUCTION TOTAL (ROUNDED) $602,250 Low range -30.0% $420,000 High Range 50.0% $900,000 NOTE: The above cost opinion is in March 2011 dollars and does not include future escalation, financial or O&M costs. The cost opinion shown has been prepared for guidance in project evaluation from the information available at the time of preparation. The final costs of the project will depend on actual labor and material costs, actual site conditions, productivity, competitive market conditions, final project scope, final schedule and other variable factors. As a result, the final project costs will vary from those presented above. Because of these factors, funding needs must be carefully reviewed prior to making specific financial decisions or establishing final budgets. ORDINANCE NO. 5611 RENTON SUNSET PLAN ACTION EIS PROJECT HARRINGTON AVE GREEN CONNECTION ORDER OF MAGNITUDE ESTIMATE DATE: PROJECT NO.: 3/9/2011 408314 . . . DESCRIPTION . . QTY UNIT TOTAL UNIT COST TOTAL COST HARRINGTON GREEN CONNECTION TOTAL LENGTH From 12th Street tolOth Street Section 1: Rain Garden on West Side of Harrington 12-ft Rain Garden Strip Section 1 Subtotal 980 700 8,400 LF LF SF $18.86 $158,414 $158,414 Section 2: Rain Garden Both Sides 12-ft Rain Garden Strip (x2) Section 2 Subtotal 112 2,688 LF SF $18.86 $50,696 $50,696 Section 3 Subtotal $0 SUBTOTAL MOBILIZATION, BONDS, INSURANCE, TEMP. FACILITIES, DEMOB, ETC 10.0% $209,110 $20,911 SUBTOTAL CONTINGENCY CONSTRUCTION TOTAL (ROUNDED) 30.0% $230,021 $69,006 $300,000 SALES TAX CONSTRUCTION TOTAL (ROUNDED) 9.5% $28,500 $328,500 Low range High Range -30.0% 50.0% $230,000 $490,000 NOTE: The above cost opinion is in March 2011 dollars and does not include future escalation, financial or O&M costs. The cost opinion shown has been prepared for guidance in project evaluation from the information available at the time of preparation. The final costs of the project will depend on actual labor and material costs, actual site conditions, productivity, competitive market conditions, final project scope, final schedule and other variable factors. As a result, the final project costs will vary from those presented above. Because of these factors, funding needs must be carefully reviewed prior to making specific financial decisions or establishing final budgets. ORDINANCE NO. 5611 RENTON SUNSET PLAN ACTION EIS PROJECT HARRINGTON AVE GREEN CONNECTION ORDER OF MAGNITUDE ESTIMATE DATE: PROJECT NO.: 3/9/2011 408314 TOTAL UNIT TOTAL DESCRIPTION QTY UNIT COST COST HARRINGTON GREEN CONNECTION TOTAL LENGTH 1,371 LF From Sunset Blvd to 9th Street Section 1: Rain Garden on West Side of Harrington 979 LF 12-ft Rain Garden Strip 11,748 SF $18.86 $221,554 Section 1 Subtotal $221,554 Section 2: Rain Garden Both Sides 157 LF 12-ft Rain Garden Strip (x2) 3,768 SF $18.86 $71,060 Section 2 Subtotal $71,060 SUBTOTAL $292,614 MOBILIZATION, BONDS, INSURANCE, TEMP. FACILITIES, DEMOB, ETC 10.0% $29,261 SUBTOTAL $321,875 CONTINGENCY 30.0% $96,563 CONSTRUCTION TOTAL (ROUNDED) $420,000 SALES TAX 9.5% $39,900 CONSTRUCTION TOTAL (ROUNDED) $459,900 Low range -30.0% $320,000 High Range 50.0% $690,000 NOTE: The above cost opinion is in March 2011 dollars and does not include future escalation, financial or O&M costs. The cost opinion shown has been prepared for guidance in project evaluation from the information available at the time of preparation. The final costs of the project will depend on actual labor and material costs, actual site conditions, productivity, competitive market conditions, final project scope, final schedule and other variable factors. As a result, the final project costs will vary from those presented above. Because of these factors, funding needs must be carefully reviewed prior to making specific financial decisions or establishing final budgets. ORDINANCE NO. 5611 RENTON SUNSET PLAN ACTION EIS PROJECT DATE: 3/9/2011 GLENNWOOD AVE STORM DRAIN PROJECT NO.: 408314 ORDER OF MAGNITUDE ESTIMATE ESTIMATE BY: D Hedglin REVIEW BY: TOTAL UNIT TOTAL • ii'.: DESCRIPTION ' QTY UNIT COST COST GLENNWOOD AVENUE 16TH ST TO 12TH ST 1,000 LF Remove Curb, Gutter & Sidewalk 1,000 LF $15.00 $15,000 Replace Curb, Gutter & Sidewalk 1,000 LF $40.00 $40,000 2-in ACP Overlay 3,333 SY $9.95 $33,167 12-in CPEP Storm Drain (1 total) 1,000 LF $81.07 $81,074 12-in CPEP Storm Drain Lateral 150 LF $81.07 $12,161 Catch Basins (at 200-ft intervals both sides) 10 EA $800.00 $8,000 Misc. Detail Allowance 1 LS $18,940.23 $18,940 Subtotal 1 $208,343 SUBTOTAL $208,343 MOBILIZATION, BONDS, INSURANCE, TEMP. FACILITIES, DEMOB, ETC 10.0% $20,834 SUBTOTAL $229,177 CONTINGENCY 30.0% $68,753 CONSTRUCTION TOTAL (ROUNDED) $300,000 SALES TAX 9.5% $28,500 CONSTRUCTION TOTAL (ROUNDED) $328,500 Low range -30.0% $230,000 High Range 50.0% $490,000 NOTE: The above cost opinion is in March 2011 dollars and does not include future escalation, financial or O&M costs. The cost opinion shown has been prepared for guidance in project evaluation from the information available at the time of preparation. The final costs of the project will depend on actual labor and material costs, actual site conditions, productivity, competitive market conditions, final project scope, final schedule and other variable factors. As a result, the final project costs will vary from those presented above. Because of these factors, funding needs must be carefully reviewed prior to making specific financial decisions or establishing final budgets. ORDINANCE NO. 5611 RENTON SUNSET PLAN ACTION EIS PROJECT DATE: 3/9/2011 12TH STREET GREEN CONNECTION PROJECT NO.: 408314 ORDER OF MAGNITUDE ESTIMATE DESCRIPTION QTY UNIT TOTAL UNIT COST TOTAL COST 12TH STREET SEG. 2 TOTAL LENGTH 1,370 LF 2 Lanes Section, Jefferson - Harrington 16-ft Rain Garden Strip Subtotal 1 620 9,920 LF SF $18.86 $187,080 $187,080 2 Lanes Section, Harrington - Edmonds 16-ft Rain Garden Strip Subtotal 2 750 12,000 LF SF $18.86 $226,306 $226,306 SUBTOTAL MOBILIZATION, BONDS, INSURANCE, TEMP. FACILITIES, DEMOB, ETC SUBTOTAL CONTINGENCY CONSTRUCTION TOTAL (ROUNDED) 10.0% 30.0% $413,386 $41,339 $454,725 $136,417 $590,000 SALES TAX CONSTRUCTION TOTAL (ROUNDED) 9.5% $56,050 $646,050 Low range High Range -30.0% 50.0% $450,000 $970,000 NOTE: The above cost opinion is in March 2011 dollars and does not include future escalation, financial or O&M costs. The cost opinion shown has been prepared for guidance in project evaluation from the information available at the time of preparation. The final costs of the project will depend on actual labor and material costs, actual site conditions, productivity, competitive market conditions, final project scope, final schedule and other variable factors. As a result, the final project costs will vary from those presented above. Because of these factors, funding needs must be carefully reviewed prior to making specific financial decisions or establishing final budgets. ORDINANCE NO. 5611 RENTON SUNSET PLAN ACTION EIS PROJECT EDMONDS AVE GREEN CONNECTION ORDER OF MAGNITUDE ESTIMATE DATE: PROJECT NO.: 3/9/2011 408314 .. - ' " DESCRIPTION QTY UNIT TOTAL UNIT COST TOTAL COST EDMONDS SEG. 3 TOTAL LENGTH 1,400 LF 3 Lanes Section, 12th-Sunset Blvd 9-ft Rain Garden Strip Subtotal 1 850 7,650 LF SF $18.86 $144,270 $144,270 3 Lanes Section, Sunset Blvd - 10th pi 9-ft Rain Garden Strip Subtotal 2 550 4,950 LF SF $18.86 $93,351 $93,351 SUBTOTAL MOBILIZATION, BONDS, INSURANCE, TEMP. FACILITIES, DEMOB, ETC SUBTOTAL CONTINGENCY CONSTRUCTION TOTAL (ROUNDED) 10.0% 30.0% $237,622 $23,762 $261,384 $78,415 $340,000 SALES TAX CONSTRUCTION TOTAL (ROUNDED) 9.5% $32,300 $372,300 Low range High Range -30.0% 50.0% $260,000 $560,000 NOTE: The above cost opinion is in March 2011 dollars and does not include future escalation, financial or O&M costs. The cost opinion shown has been prepared for guidance in project evaluation from the information available at the time of preparation. The final costs of the project will depend on actual labor and material costs, actual site conditions, productivity, competitive market conditions, final project scope, final schedule and other variable factors. As a result, the final project costs will vary from those presented above. Because of these factors, funding needs must be carefully reviewed prior to making specific financial decisions or establishing final budgets. ORDINANCE NO. 5611 RENTON SUNSET PLAN ACTION EIS PROJECT EDMONDS AVE GREEN CONNECTION ORDER OF MAGNITUDE ESTIMATE DATE: PROJECT NO.: 3/9/2011 408314 DESCRIPTION QTY UNIT TOTAL UNIT COST TOTAL COST EDMONDS SEG. 4 TOTAL LENGTH 1,600 LF 2 Lanes Section, 10th pi - 6th Street Subtotal 1 1,600 LF $482,787 SUBTOTAL MOBILIZATION, BONDS, INSURANCE, TEMP. FACILITIES, DEMOB, ETC SUBTOTAL CONTINGENCY CONSTRUCTION TOTAL (ROUNDED) 10.0% 30.0% $482,787 $48,279 $531,065 $159,320 $690,000 SALES TAX CONSTRUCTION TOTAL (ROUNDED) 9.5% $65,550 $755,550 Low range High Range -30.0% 50.0% $530,000 $1,130,000 NOTE: The above cost opinion is in March 2011 dollars and does not include future escalation, financial or O&M costs. The cost opinion shown has been prepared for guidance in project evaluation from the information available at the time of preparation. The final costs of the project will depend on actual labor and material costs, actual site conditions, productivity, competitive market conditions, final project scope, final schedule and other variable factors. As a result, the final project costs will vary from those presented above. Because of these factors, funding needs must be carefully reviewed prior to making specific financial decisions or establishing final budgets. ORDINANCE NO. 5611 RENTON SUNSET PLAN ACTION EIS PROJECT DATE: 3/9/2011 KIRKLAND AVE STORM DRAIN PROJECT NO.: 408314 ORDER OF MAGNITUDE ESTIMATE ESTIMATE BY: D Hedglin REVIEW BY: TOTAL UNIT TOTAL DESCRIPTION QTY UNIT COST COST KIRKLAND AVENUE 16TH ST TO 12TH ST 1,450 LF Remove Curb, Gutter & Sidewalk 1,450 LF $15.00 $21,750 Replace Curb, Gutter & Sidewalk 1,450 LF $40.00 $58,000 2-in ACP Overlay 4,833 SY $9.95 $48,092 24-in CPEP Storm Drain (1 total) 1,450 LF $133.04 $192,906 12-in CPEP Storm Drain Lateral 218 LF $81.07 $17,634 Catch Basins (at 200-ft intervals both sides) 15 EA $800.00 $11,680 Misc. Detail Allowance 1 LS $35,006.14 $35,006 Subtotal 1 $385,068 SUBTOTAL $385,068 MOBILIZATION, BONDS, INSURANCE, TEMP. FACILITIES, DEMOB, ETC 10.0% $38,507 SUBTOTAL $423,574 CONTINGENCY 30.0% $127,072 CONSTRUCTION TOTAL (ROUNDED) $550,000 SALES TAX 9.5% $52,250 CONSTRUCTION TOTAL (ROUNDED) $602,250 Low range -30.0% $420,000 High Range 50.0% $900,000 NOTE: The above cost opinion is in March 2011 dollars and does not include future escalation, financial or O&M costs. The cost opinion shown has been prepared for guidance in project evaluation from the information available at the time of preparation. The final costs of the project will depend on actual labor and material costs, actual site conditions, productivity, competitive market conditions, final project scope, final schedule and other variable factors. As a result, the final project costs will vary from those presented above. Because of these factors, funding needs must be carefully reviewed prior to making specific financial decisions or establishing final budgets. ORDINANCE NO. 5611 RENTON SUNSET PLAN ACTION EIS PROJECT JEFFERSON GREEN CONNECTION ORDER OF MAGNITUDE ESTIMATE DATE: PROJECT NO.: 3/9/2011 408314 DESCRIPTION QTY UNIT TOTAL UNIT COST TOTAL COST JEFFERSON GREEN CONNECTION TOTAL LENGTH 1,300 LF Section 1: Rain Garden on one side of Steet 12-tt Rain Garden Strip Section 1 Subtotal 850 10,200 LF SF ; $18.86 $192,360 $192,360 Section 2: Rain Garden both Sides of Street 12-ft Rain Garden Strip (x2) Section 2 Subtotal 150 3,600 LF SF $14.26 $51,336 $51,336 SUBTOTAL MOBILIZATION, BONDS, INSURANCE, TEMP. FACILITIES, DEMOB, ETC SUBTOTAL CONTINGENCY CONSTRUCTION TOTAL (ROUNDED) 10.0% 30.0% $243,696 $24,370 $268,066 $80,420 $350,000 SALES TAX CONSTRUCTION TOTAL (ROUNDED) 9.5% $33,250 $383,250 Low range High Range -30.0% 50.0% $270,000 $570,000 NOTE: The above cost opinion is in March 2011 dollars and does not include future escalation, financial or O&M costs. The cost opinion shown has been prepared for guidance in project evaluation from the information available at the time of preparation. The final costs of the project will depend on actual labor and material costs, actual site conditions, productivity, competitive market conditions, final project scope, final schedule and other variable factors. As a result, the final project costs will vary from those presented above. Because of these factors, funding needs must be carefully reviewed prior to making specific financial decisions or establishing final budgets. ORDINANCE NO. 5611 Appendix D Hydrologic and Hydraulic Model Output ORDINANCE NO. 5611 Appendix Dl - Sub-Regional Flow Control Facility ORDINANCE NO. 5611 MODELING LOG CH2MHILL Run Description Sheet MODELER: REVIEWER: PROJECT: CLIENT: PROJECT NUBER: DATE: Raymond Chung/SEA Dustin Atchison/SEA Renton Sunset Terrace City of Renton 408314 April 14 2011. RUN NO: RF 1 MODEL USED: WWHM (ver3) DRIVE AND PATH: \\ simba\ proj\ Renton WACityOf \408314\ 9_Stormwater\ Analysis\ RegionalDet ention PURPOSE OF RUN: Preliminary determine the size of a regional detention size needed to control the peak flow rate for the additional 2.6 ac of impervious per FEIS Preferred Alternative. WQ design flow go to infiltration to native soil (0.25"/hr) while the high flow go to a detention vault. Input Description FILE NAMES: RF 1 COMMENTS: Scale Factor = 1.0 using SeaTac gage. The new impervious area estimated to be detained is 2.6 ac. Adding 10% safety factor, tire detention facility to be sized fro 2.9 ac. The water will flow thru rain garden for treatment with 1.5"/hr of infiltration rate. Rain garden 6" was ponding, and 18" of compost soil with 30% void. A total of 0.95 feet of storage and 1.45 feet deep with freeboard. Infiltration gallery assumes 18" of gravel with 30% void and underdrain pipe. Output Description FILE NAMES: RF_Sunset.doc SEA/MODELLOG JREGI0NALFACIUTY.DOC 1 1 ORDINANCE NO. 5611 RUN DESCRIPTION SHEET COMMENTS: See output summary. The release rate from the detention vault meets the Peak flow rate matching standard. All the water quality flow is infiltrated into native ground. Rain Garden Vault Infiltration Gallery Pond Dimensions Bottom Length x Width (feet) 155x20 135x20 125x100 Depth (feet) 1.45 6.5 3 Side slopes (H:V) 4 Vert Vert Discharqe Structure Riser Height (feet) 0.95 6 2.9 Riser Diameter (in) 18 18 Orifice 1 Diameter (in) 0 1.75 Orifice 1 Height (feet) 0 0 Orifice 2 Diameter (in) 0 2.2 Orifice 2 Height (feet) 0 3.5 Orifice 3 Diameter (in) 0 1.5 Orifice 3 Height (feet) 0 5 Modeled Infiltration Rate (inches/hour) 1.5 0 0.25 Side infiltration Off Off Off Evaporation On Off Off Precipitation on Facility On Off Off SEA/M0DELL0G_REGI0NALFACIUTY.D0C 2 2 ORDINANCE NO. 5611 Western Washington Hydrology Model PROJECT REPORT Project Name Site Address City Report Date Gage Data Start Data End Precip Scale WWHM3 Version: RF__1 Renton 4/15/2011 Seatac 1948/10/01 1998/09/30 1. 00 PREDEVELOPED LAND USE Name : Basin 1 Bypass: No Groundwater: No Pervious Land Use C, Lawn, Flat Impervious Land Use Acres 2.9 Acres Element Flows To: Surface Interflow Groundwater Name : 10000SF Bypass: No Groundwater: No Pervious Land Use Acres Impervious Land Use Acres ROADS FLAT 2.9 Element Flows To: Surface Interflow Groundwater etention Rain Garden, etention Rain Garden, Name : etention Rain Garden Bottom Length: 155ft. Bottom Width: 20ft. ORDINANCE NO. 5611 Depth : 1.45ft. Volume at riser head : 0.0826ft. Infiltration On Infiltration rate : 1.5 Infiltration saftey factor : 1 Side slope 1: 4 To 1 Side slope 2: 4 To 1 Side slope 3: 4 To 1 Side slope 4: 4 To 1 Discharge Structure Riser Height: 0.95 ft. Riser Diameter: 18 in. Element Flows To: Outlet 1 Outlet 2 Detention Vault 1, Infiltration Bed, Pond Hydraulic Table Stage(ft) Area(acr) Volume(acr-ft) Dschrq(cfs) Infilt(cfs) 0 . . 000 0 . .071 0. .000 0. . 000 0. . 000 0. . 016 0 . . 072 0. .001 0. .000 0 . . 108 0 . . 032 0 . . 072 0. .002 0. , 000 0 . .108 0 . . 048 0 . . 073 • 0 . . 003 0. . 000 0. .108 0 . . 064 0 . .073 0 . .005 0. , 000 0. .108 0 . .081 0 . .074 0 . . 006 0. .000 0. .108 0 . . 097 0. ,074 0 . . 007 0 . .000 0. .108 0 . .113 0. .075 0 . .008 0 . .000 0 . , 108 0 . . 129 0. .075 0 . . 009 0. .000 0. .108 0. .145 0. .076 0. . 011 0 . .000 0. . 108 0. .161 0. .076 0 . . 012 0 . .000 0. . 108 0 . .177 0. .077 0 . . 013 0. .000 0. . 108 0 . . 193 0. .077 0 . . 014 0 . .000 0. ,108 0. .209 0. .078 0 . .016 0 . .000 0. , 108 0 . .226 0. . 078 0. . 017 0 . .000 0. , 108 0. .242 0. .079 0. .018 0 . .000 0. . 108 0 . .258 0. .080 0. .019 0. . 000 0. .108 0. .274 0 . .080 0 . .021 0. . 000 0. . 108 0. .290 0. .081 0. .022 0. .000 0 . .108 0 . .306 0 . .081 0. .023 0. . 000 0. . 108 0 . .322 0 . .082 0. . 025 0. . 000 0 . . 108 0 . .338 0 . .082 0. . 026' 0. . 000 0 . .108 0 , .354 0 . . 083 0 . . 027 0. .000 0 . . 108 0 . .371 0 . .083 0 . .029 0. .000 0 . . 108 0 , .387 0 . .084 0 . .030 0. .000 0 . . 108 0 . .403 0. .084 0 . .031 0. .000 0 . .108 0 . .419 0. .085 0 . .033 0 . .000 0. . 108 0 . .435 0. . 085 0 , . 034 0 . .000 0. .108 0 . . 451 0. .086 0 . .035 0 . .000 0. . 108 0 . . 467 0. .087 0 . . 037 0 . .000 0. .108 0 . . 483 0 , .087 0 . .038 0, . 000 0. .108 0. . 499 0 . .088 0 . .040 0. .000 0 , .108 0. .516 0 , .088 0. .041 0. . 000 0. . 108 0. .532 0 , .089 0. .042 0. . 000 0. . 108 0 .548 0 , .089 0. . 044 0. . 000 0. . 108 ORDINANCE NO. 5611 0.564 0.580 0.596 0 .612 0 .628 0 .644 0 .661 0 .677 0.693 0 . 709 0 . 725 0 . 741 0 . 757 0 . 773 0.789 0 . 806 0. 822 0 . 838 0 . 854 0 .870 0 . 886 0 . 902 0 . 918 0 . 934 0 . 951 0 . 967 0 . 983 0 . 999 1.015 1. 031 1. 047 1.063 1 . 079 1.096 1 .112 1 .128 1 .144 1.160 1.176 1.192 1.208 1.224 1.241 1.257 1.273 1.289 1.305 1.321 1.337 1 .353 1.369 1.386 1. 402 1. 418 1.434 1. 450 0 . 090 0 . 090 0 . 091 0 . 091 0 . 092 0 . 092 0 . 093 0.094 0.094 0.095 0 . 095 0.096 0.096 0.097 0 . 097 0.098 0.099 0 . 099 0 .100 0 .100 0. 101 0 . 101 0. 102 0 . 102 0 . 103 0 . 104 0 . 104 0.105 0 . 105 0.106 0 . 106 0 . 107 0 .108 0 . 108 0 .109 0 .109 0 .110 0 .110 0 . Ill 0 .112 0 .112 0 . 113 0 . 113 0 . 114 0 . 114 0 . 115 0 . 116 0 . 116 0 .117 0 .117 0 .118 0 .119 0 .119 0 . 120 0 . 120 0 . 121 0 . 045 0 . 047 0 . 048 0 . 050 0.051 0 . 053 0 . 054 0.056 0.057 0.059 0.060 0.062 0.063 0.065 0 . 066 0.068 0 . 070 0 . 071 0 . 073 0.074 0 . 076 0 . 078 0 . 079 0 . 081 0 . 083 0.084 0.086 0.088 0 . 089 0.091 0.093 0 . 094 0.096 0.098 0 .100 0 .101 0.103 0 .105 0 .107 0.109 0 .110 0.112 0 . 114 0 .116 0 .118 0 .119 0 .121 0.123 0 .125 0 .127 0 .129 0.131 0 .133 0.135 0 .137 0 .138 0 . 000 0 . 000 0 . 000 0 . 000 0 . 000 0 . 000 0 . 000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0 .000 0.000 0 . 000 0 . 000 0 .000 0 . 000 0.000 0.000 0 . 000 0. 000 0.000 0.031 0 . 087 0 .158 0.242 0.337 0 . 443 0.557 0 .680 0.811 0 . 950 1.095 1.247 1.406 1.571 1.742 1.918 2 .100 2.288 2 . 481 2.679 2.882 3.090 3.303 3.520 3 . 742 3.968 4.199 4 . 434 4.674 4.917 5 .165 0 .108 0 .108 0 .108 0 .108 0.108 0 .108 0 .108 0 .108 0 .108 0 .108 0 .108 0 .108 0 .108 0.108 0.108 0.108 0.108 0.108 0.108 0.108 0.108 0.108 0.108 0 .108 0 .108 0 .108 0 .108 0 .108 0 .108 0 .108 0 .108 0.108 0 .108 0 .108 0 .108 0.108 0 .108 0 .108 0.108 0.108 0.108 0 .108 0 .108 0 .108 0 .108 0 .108 0 .108 0 .108 0 .108 0 .108 0 .108 0 .108 0.108 0.108 0.108 0 .108 ORDINANCE NO. 5611 Name : Infiltration Bed Bottom Length: 125ft. Bottom Width : 100ft. Trench bottom slope 1: 0.005 To 1 Trench Left side slope 0: 0.1 To 1 Trench right side slope 2: 0.1 To 1 Material thickness of first layer : 3 Pour Space of material for first layer : 0.33 Material thickness of second layer : 0 Pour Space of material for second layer : 0 Material thickness of third layer : 0 Pour Space of material for third layer : 0 Infiltration On Infiltration rate : 0.25 Infiltration saftey factor : 1 Discharge Structure Riser Height: 2.9 ft. Riser Diameter: 18 in. Element Flows To: Outlet 1 Outlet 2 Gravel Trench Bed Hydraulic Table Stage(ft) Area(acr) Volume(acr-ft) Dschrg(cfs) Infilt(cfs) 0. . 000 0. .287 0 . . 000 0. . 000 0 . .000 0 . . 033 0. .287 0. .003 0 . .000 0. .072 0. . 067 0. .287 0 . . 006 0. .000 0. .072 0 . .100 0 . . 287 0. .009 0 . .000 0 . .072 0 . .133 0. . 287 0. . 013 0 . .000 0. .072 0. .167 0. .287 0 . . 016 0 . . 000 0 . .072 0 . .200. 0. .287 0 . . 019 0 . .000 0 . .072 0 . .233 0. .287 0. . 022 0 . . 000 0 . .072 0 . .267 0. .287 0 . . 025 0 . . 000 0 . .072 0 . .300 0. .287 0 . . 028 0 . . 000 0. .072 0 . .333 0. .287 0 . . 032 0 . . 000 0. .072 0 . .367 0. .287 0 . . 035 0 . . 000 0 . .072 0 . . 400 0. . 287 0 . . 038 0. . 000 0. .072 0. . 433 0. .287 0 . . 041 0 . . 000 0. .072 0. .467 0. .287 0 . . 044 0 . . 000 0. .072 0 . .500 0 . .287 0 . . 047 0. .000 0 . .072 0 . .533 0. .287 0. .051 0 . .000 0. .072 0 . .567 0. .287 0 . . 054 0 . .000 0. .072 0 . .600 0 . .287 0. . 057 0 . . 000 0 . .072 0 . . 633 0. .287 0. . 060 0 . . 000 0. .072 0 . .667 0. .287 0. . 063 0 . . 000 0 . .072 0. . 700 0. .287 0 . . 066 0 . . 000 0 . .072 0 . . 733 0. .287 0 . . 069 0 . . 000 0. .072 0. . 767 0 . .287 0 . .073 0 . .000 0 . . 072 0. .800 0 . .287 0 . .076 0. .000 0 . . 072 0 . . 833 0 , .287 0. .079 0 . .000 0 . . 072 0. . 867 0 . .287 0 . .082 0 . .000 0 . . 072 0 . .900 0 . .287 0. .085 0. .000 0 . .072 0. .933 0. .288 0. .088 0 . .000 0 . . 072 ORDINANCE NO. 5611 0 .967 0 .288 0 .092 0 . 000 0 .072 1 .000 0 .288 0 . 095 0 . 000 0 .072 1 . 033 0 .288 0 .098 0 . 000 0 .072 1 . 067 0 .288 0 .101 0 .000 0 .072 1 . 100 0 .288 0 .104 0 . 000 0 .072 1 . 133 0 .288 0 .107 0 . 000 0 .072 1 . 167 0 .288 0 .111 0 . 000 0 .072 1 .200 0 .288 0 .114 0 .000 0 .072 1 .233 0 .288 0 .117 0 . 000 0 .072 1 .267 0 .288 0 . 120 0 . 000 0 .072 1 .300 0 .288 0 . 123 0 . 000 0 .072 1 .333 0 .288 0 .126 0 .000 0 .072 1 .367 0 .288 0 .130 0 . 000 0 .072 1 . 400 0 .288 0 . 133 0 .000 0 .072 1 .433 0 .288 0 . 136 0 . 000 0 .072 1 .467 0 .288 0 .139 0 .000 0 072 1 .500 0 .288 0 .142 0 .000 0 072 1 533 0 .288 0 145 0 . 000 0 072 1 567 0 .288 0 149 0 .000 0 072 1 600 0 288 0 152 0 .000 0 072 1 633 0 288 0 155 0 000 0 072 1 667 0 288 0 158 0 000 0 072 1 700 0 288 0 161 0 000 0 072 1 733 0 288 0 164 0 000 0 072 1 767 0 288 0 168 0 000 0 072 1 800 0 288 0 171 0 000 0 072 1 833 0 288 0 174 0 000 0 072 1 867 0 288 0 177 0 000 0 072 1 900 0 288 0 180 .0 000 0 072 1 933 0 288 0 183 0 000 0 072 1 967 0 288 0 187 0 000 0 072 2 000 0 288 0 190 0 000 0 072 2 033 0 288 0 193 0 000 0 072 2 067 0 288 0 196 0 000 0 072 2 100 0 288 0 199 0 000 0 072 2 133 0 288 0 202 0 000 0 072 2 167 0 288 0 206 0 000 0 072 2 . 200 0 288 0 209 0 000 0 072 2 . 233 0 288 0. 212 0 000 0. 072 2 . 267 0 288 0. 215 0 000 0 . 072 2 . 300 0 . 288 0 . 218 0. 000 0 . 072 2 . 333 0 . 288 0 . 221 0. 000 0 . 072 2 . 367 0 . 288 0 . 225 0 . 000 0 . 072 2 . 400 0 . 288 0. 228 0 . 000 0. 072 2 . 433 0. 288 0. 231 0 . 000 0. 072 2 . 467 0 . 288 0. 234 0 . 000 0 . 072 2 . 500 0 . 288 • 0. 237 0. 000 0 . 072 2 . 533 0. 288 0 . 241 0. 000 0 . 072 2 . 567 0 . 288 0 . 244 0. 000 0 . 072 2 . 600 0 . 289 0. 247 0. 000 0 . 072 2 . 633 0. 289 0 . 250 0. 000 0 . 072 2 . 667 0 . 289 0 . 253 0. 000 0 . 072 2 . 700 0 . 289 0 . 256 0. 000 0 . 072 2 . 733 0. 289 0 . 260 0. 000 0 . 072 2 . 767 0 . 289 0. 263 0 . 000 0. 072 2 . 800 0 . 289 0. 266 0 . 000 0. 072 2 . 833 0 . 289 0 . 269 0. 000 0 . 072 ORDINANCE NO. 5611 2 . 867 2 . 900 2 . 933 2 . 967 3 . 000 0.289 0.289 0.289 0 .289 0.289 0 .272 0.275 0 . 279 0 .282 0 . 285 0 . 000 0 .000 0 .089 0.251 0.462 0 .072 0 .072 0 .072 0 .072 0 .072 Name : Detention Vault 1 Width : 20 ft. Length : 135 ft. Depth: 6.5ft. Discharge Structure Riser Height: 6 ft. Riser Diameter: 18 in. Orifice 1 Diameter: 1.75 in. Elevation: 0 ft. Orifice 1 Diameter: 2.2 in. Elevation: 3.5 ft. Orifice 1 Diameter: 1.5 in. Elevation: 5 ft. Element Flows To: Outlet 1 Outlet 2 Vault Hydraulic Table Stage(ft) Area(acr) Volume(acr-ft) Dschrq(cfs) Infilt(cfs) 0 . . 000 0 . .062 0. . 000 0 . .000 0 . .000 0 . .072 0 . .062 0. . 004 0 . . 022 0 . ,000 0. . 144 0 . .062 0. . 009 0 . .031 0 . .000 0 . .217 0. .062 0 . . 013 0 . . 037 0. ,000 0 . .289 0 . .062 0. . 018 0 . .043 0 . .000 0 . .361 0 . .062 0. . 022 0 . . 048 0 . .000 0 . .433 0. .062 0 . . 027 0 . . 053 0 . .000 0 . .506 0 . . 062 0. . 031 0. . 057 0 . .000 0 . .578 0. . 062 0 . .036 0 . . 061 0 . .000 0 . .650 0. . 062 0 . .040 0 . . 065 0 . .000 0 . . 722 0 . . 062 0 . .045 0 . . 068 0. .000 0 . . 794 0. . 062 0 . .049 0 . .072 0 . .000 0 . .867 0. . 062 0 . . 054 0 . .075 0. .000 0 . . 939 0 . . 062 0 . . 058 0. .078 0 . .000 1. . 011 0 . .062 0 . .063 0 . .081 0 . . 000 1. . 083 0 . . 062 0 . . 067 0 . .084 0 . .000 1. . 156 0 . . 062 0 . .072 0. .086 0 . .000 1. .228 0 . . 062 0. .076 0 . .089 0 . . 000 1. .300 0 . .062 0 . . 081 0 , .092 0. . 000 1. .372 0 . .062 0 . . 085 0 , . 094 0. . 000 1. . 444 0 . .062 0 . . 090 0 , . 097 ' 0. . 000 1. .517 0 . .062 0 . . 094 0 , . 099 0. . 000 1. .589 0 . .062 0 . . 098 0 , . 101 0 . . 000 1. . 661 0 . .062 0. . 103 0. .104 0 . .000 1. . 733 0 . .062 0 . .107 0 , . 106 0 . . 000 1, .806 0 , . 062 0 , .112 0. . 108 0 . .000 1, .878 0 , . 062 0 , .116 0. . 110 0 . .000 1. .950 0. .062 0 . . 121 0 . . 112 0 . . 000 2 , . 022 0 , . 062 0 . . 125 0. . 114 0 . .000 2 , . 094 0 . . 062 0 . . 130 0. .116 0 . .000 2 . .167 • 0 , . 062 0 . . 134 0 .118 0 . .000 ORDINANCE NO. 5611 2 .239 0 . 062 0 . 139 0 . 120 0 .000 2 .311 0 . 062 0 . 143 0 . 122 0 . 000 2 .383 0 . 062 0 . 148 0 . 124 0 .000 2 . 456 0 . 062 0 . 152 0 . 126 0 .000 2 .528 0 .062 0 . 157 0 .128 0 .000 2 .600 0 . 062 0 .161 0 . 130 0 . 000 2 .672 0 . 062 0 . 166 0 . 131 0 .000 2 . 744 0 . 062 0 .170 0 . 133 0 .000 2 . 817 0 . 062 0 .175 0 . 135 0 .000 2 .889 0 . 062 0 .179 ' 0 . 137 0 .000 2 . 961 0 . 062 0 .184 0 . 138 0 .000 3 . 033 0 . 062 0 .188 0 . 140 0 .000 3 .106 0 . 062 0 .192 0 . 142 0 .000 3 . 178 0 . 062 0 .197 0 . 143 0 .000 3 .250 0 . 062 0 .201 0 .145 0 .000 3 .322 0 . 062 0 .206 0 . 147 0. .000 3 .394 0 .062 0 .210 0 . 148 0. . 000 3 . 467 0 . 062 0 .215 0 . 150 0 .000 3 .539 0 . 062 0 .219 0 .176 0, . 000 3 .611 0 . 062 0 .224 0 .195 0 . .000 3 .683 0 . 062 0 .228 0. .209 0 . . 000 3 . 756 0 . . 062 0 .233 0 . .220 0. . 000 3. . 828 0 . . 062 0. .237 0 , .230 0. . 000 3, .900 0 , . 062 0. .242 0 , .239 0. .000 3 . .972 0. .062 0. .246 0. .248 0 . .000 4 , . 044 0. . 062 0. .251 0 . . 256 0 . . 000 4. . 117 0 . . 062 0. .255 0 . .263 0. .000 4 . .189 0. .062 0 . .260 0. .270 0. .000 4 . .261 0. .062 .0. .264 0. .277 0 . .000 4 . .333 0. .062 0. .269 0. .283 0 . . 000 4 . . 406 0. .062 0 . .273 0. .290 0 . . 000 4. . 478 0. . 062 0 . .278 0. .296 0. .000 4 . .550 0. .062 0 . .282 0. .302 0. 000 4 . . 622 0. .062 0. .287 0 . .308 0 . 000 4 . .694 0. . 062 0. .291 0 . .313 0. 000 4 . . 767 0. .062 0 . .295 0. 319 0 . 000 4 . . 839 0. .062 0 . .300 0. 324 0. 000 4. .911 0 . 062 0. .304 0 . 329 0. 000 4 . .983 0 . 062 0. .309 0. 334 0. 000 5 . 056 0. 062 0. 313 0. 353 0 . 000 5 . 128 0 . 062 0. 318 0 . 365 0. 000 5 . 200 0 . 062 0 . 322 0 . 376 0. 000 5 . 272 0 . 062 0 . 327 0 . 385 0. ooo 5 . 344 0 . 062 0. 331 0. 393 0. 000 5 . 417 0 . 062 0. 336 0 . 401 0 . 000 5 . 489 0. 062 0. 340 0. 409 0 . 000 5 . 561 0 . 062 0 . 345 0. 416 0. 000 5 . 633 0 . 062 0. 349 0 . 424 0. 000 5 . 706 0 . 062 0 . 354 0 . 431 0. 000 5 . 778 0 . 062 0. 358 0 . 437 0. 000 5 . 850 0. 062 0. 363 0. 444 0. 000 5 . 922 0 . 062 0. 367 0 . 450 0. 000 5 . 994 0 . 062 0 . 372 0 . 457 0. 000 6 . 067 0 . 062 0 . 376 0 . 714 0. 000 6 . 139 0. 062 0 . 381 1. 225 0. 000 6 . 211 0. 062 0. 385 1. 892 0. 000 6 . 283 0. 062 0. 389 2 . 684 0. 000 ORDINANCE NO. 5611 6 .356 6 . 428 6 .500 6 .572 6 .644 0 . 062 0 . 062 0 . 062 0 . 062 0 . 000 0.394 0.398 0.403 0.407 0 . 000 3 . 584 4.579 5.662 6.827 8 . 066 0.000 0.000 0.000 0 .000 0 . 000 MITIGATED LAND USE ANALYSIS RESULTS Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.146865 5 year 0.231604 10 year 0.295364 25 year 0.384285 50 year 0.456469 100 year 0.533678 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.127516 5 year 0.208151 10 year 0.270392 25 year 0.358881 50 year 0.43189 100 year 0.510955 Yearly Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitig 1950 0 . . 180 0 . . 115 1951 0. .475 0 . . 125 1952 0. .244 0 . .285 1953 0 . . 110 0. .096 1954 0 . . 078 0. .103 1955 0 . . 137 0. .078 1956 0 . .187 0. .230 1957 0 . . 185 0. . 138 1958 0 . .201 0. . 134 1959 0 . . 127 ' 0. . 121 1960 0 . .097 0 . . 122 1961 0. .218 0 . .280 1962 0. . 122 0 . . 115 1963 0. .072 0 . . 074 1964 0. . 127 0 . . 101 1965 0. .143 0 . . 090 1966 0. .104 0 . .124 1967 0 . .119 0. .081 1968 0. .222 0 . . 147 1969 0 . . 158 0. .090 1970 0. . 122 0 . . 121 1971 0. . 128 0 . . 109 1972 0. . 137 0. . 104 ORDINANCE NO. 5611 1973 0. .298 0. .177 1974 0. .105 0. . 094 1975 0. .140 0. . 069 1976 0. .246 0. .207 1977 0. . 137 0 . .106 1978 0. .052 0. . 086 1979 0. .149 0. . 125 1980 0 . . 064 0 . .074 1981 0 . .192 0 . . 199 1982 0 . . 164 0 . . 106 1983 0 . .347 0 . .364 1984 0 . . 137 0 . . 120 1985 0 . . 129 0 . . 096 1986 0 . .072 0 . . 119 1987 0 . .251 0 . .312 1988 0 . .228 0 . .331 1989 0 . .088 0 . . 095 1990 0. .062 0 . .031 1991 0. . 498 0. .398 1992 0. .410 0. .387 1993 0. . 124 0. . 099 1994 0. .097 0. . 108 1995 0. .047 0. . 028 1996 0. . 129 0. .119 1997 0 . .309 0 . .276 1998 0. .228 0. .380 1999 0. . 151 0. . 105 Ranked Yearly Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1. 0 . . 4985 0 . .3980 2 0 . . 4752 0 . .3866 3 0 . . 4102 0 . .3802 4 0 . .3466 0. .3637 5 0. .3086 0 . .3312 6 0. .2979 0 . .3120 7 0 . .2509 0 . .2849 8 0 . .2456 0 . .2796 9 0 . .2435 0. .2759 10 0 . .2280 0 . .2299 11 0 . .2279 0. .2072 12 0 . .2218 0. . 1993 13 0 . .2176 0 . . 1769 14 0 . .2015 0. . 1474 15 0 . .1919 0 . . 1379 16 0. .1872 0 , . 1337 17 0 . .1849 0. . 1254 18 0 . . 1805 0. . 1253 19 0 . . 1637 0 , . 1240 20 0 . . 1575 0 . . 1224 21 0 . . 1508 0 . . 1214 22 0 , . 1491 0 . . 1211 23 0 , .1435 0 . .1198 24 0. . 1404 0 . . 1194 25 0. .1374 0 .1187 26 0 , .1372 0 .1154 ORDINANCE NO. 5611 27 0.1369 0.1147 28 0.1366 0.1094 29 0.1289 0.1082 30 0.1288 0.1063 31 0.1279 0.1060 32 0.1274 0.1046 33 0.1271 0.1037 34 0.1238 0.1030 35 0.1224 0.1013 36 0.1222 0.0989 37 0.1192 0.0965 38 0.1095 0.0960 39 0.1049 0.0952 40 0.1043 0.0939 41 0.0974 0.0901 42 0.0972 0.0897 43 0.0878 0.0860 44 0.0784 0.0808 45 0.0724 0.0776 46 0.0717 0.0740 47 0.0645 0.0738 48 0.0621 0.0687 49 0.0520 0.0308 50 0.0466 0.0282 POC #1 Facility FAILED duration standard for 1+ flows. Flow(CFS) Predev Dev Percentage Pass/Fail 0. .0734 2357 1986 84 Pass 0. .0773 2032 1802 88 Pass 0. .0812 1754 1634 93 Pass 0 . . 0850 1555 1475 94 Pass 0. .0889 1420 1350 95 Pass 0. . 0928 1238 1195 96 Pass 0 . . 0966 1094 1056 96 Pass 0 . . 1005 974 926 95 Pass 0 . . 1044 861 816 94 Pass 0 . .1083 770 702 91 Pass 0 . .1121 687 608 88 Pass 0 . . 1160 627 540 86 Pass 0 . . 1199 556 464 83 Pass 0 . . 1237 485 396 81 Pass 0 . . 1276 442 353 79 Pass 0. .1315 396 319 80 Pass 0 . . 1353 356 274 76 Pass 0 . . 1392 317 242 76 Pass 0 . .1431 283 214 75 Pass 0 . . 1469 270 194 71 Pass 0 . . 1508 247 178 72 Pass 0 . . 1547 224 173 77 Pass 0 . . 1586 206 170 82 Pass 0. . 1624 183 166 90 Pass 0 . .1663 159 163 102 Pass 0 . . 1702 141 160 113 Fail ORDINANCE NO. 5611 0 .1740 125 155 124 Fail 0 .1779 115 154 133 Fail 0 . 1818 97 149 153 Fail 0 . 1856 87 144 165 Fail 0 . 1895 74 139 187 Fail 0 . 1934 66 133 201 Fail 0 . 1972 60 131 218 Fail 0 .2011 58 128 220 Fail 0 .2050 52 124 238 Fail 0 .2088 47 123 261 Fail 0 .2127 44 120 272 Fail 0 .2166 43 119 276 Fail 0 . 2205 39 116 297 Fail 0 .2243 34 113 332 Fail 0 .2282 31 102 329 Fail 0 . 2321 28 96 342 Fail 0 . 2359 27 90 333 Fail 0 .2398 25 88 352 Fail 0 .2437 21 80 380 Fail 0 . 2475 18 78 433 Fail 0 .2514 17 77 452 Fail 0 .2553 17 75 441 Fail 0 .2591 16 70 437 Fail 0 . .2630 15 67 446 Fail 0 . . 2669 15 65 433 Fail 0 . .2708 14 60 428 Fail 0 , .2746 13 56 430 Fail 0 . .2785 12 50 416 Fail 0 . .2824 12 47 391 Fail 0 . .2862 10 39 390 Fail 0 . . 2901 10 36 360 Fail 0 . .2940 10 35 350 Fail 0 . .2978 10 34 340 Fail 0 . .3017 9 30 333 Fail 0 . .3056 9 30 333 Fail 0 . .3094 8 28 350 Fail 0 . 3133 8 27 337 Fail 0 . 3172 8 25 312 Fail 0 . 3211 8 21 262 Fail 0 . 3249 8 20 250 Fail 0 . 3288 8 19 237 Fail 0 . 3327 8 16 200 Fail 0 . 3365 8 16 200 Fail 0 . 3404 7 16 228 Fail 0. 3443 7 16 228 Fail 0 . 3481 6 16 266 Fail 0 . 3520 6 16 266 Fail 0. 3559 6 14 233 Fail 0 . 3597 6 12 200 Fail 0. 3636 6 10 166 Fail 0 . 3675 6 8 133 Fail 0 . 3713 6 8 133 Fail 0 . 3752 6 8 133 Fail 0 . 3791 6 6 100 Pass 0 . 3830 6 5 83 Pass 0 . 3868 6 5 83 Pass 0 . 3907 6 4 66 Pass ORDINANCE NO. 5611 0.3946 0.3984 0.4023 0.4062 0.4100 0.4139 0.4178 0.4216 0.4255 0.4294 0.4333 0.4371 0.4410 0.4449 0.4487 0.4526 0.4565 5 5 5 5 5 4 4 4 4 4 4 3 3 3 3 3 2 4 3 2 1 1 1 0 0 0 0 0 0 0 0 0 0 0 80 60 40 20 20 25 0 0 0 0 0 0 0 0 0 0 0 Pass Pass Pass Pass Pass Pass Pass Pass Pass Pass Pass Pass Pass Pass Pass Pass Pass 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. 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. Perlnd and Implnd Changes No changes have been made. This program and accompanying documentation is provided 'as-is' without warranty of any kind. The entire risk regarding the performance and results of this program is assumed by the user. Clear Creek Solutions and the Washington State Department of Ecology disclaims all warranties, either expressed or implied, including but not limited to implied warranties of program and accompanying documentation. In no event shall Clear Creek Solutions and/or the Washington State Department of Ecology 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 or the Washington State Department of Ecology has been advised of the possibility of such damages. 14 ORDINANCE NO. 5611 Figure 1. Screen Capture of the Rain Garden Input and Infiltration Output •^t 6JS S** btp I rm n^Tca i rai 1 W\ I j-^^l pgH-iD Facilfly Name Downstream Connections iFacilitvType Facility Bottom Elevation (fl) |tr Facility Dimensions Bottom Length 1M) • BMIomWtfih(K) Etfei*ye-Dwilh|ll! Side Slope (HAH |ffcitom Site Slope |HiV} [RisMSide Slope (HiV| Top Siie Slope (IWf Facility Dimension Diagram. 'Infiltration jYES led Irrtiabai Rale fmJtt) ffT IRaiioiioriFjictoten»i«ac>) ]i Outlet Structure • Rjsa He&il (ft) • ' ft • Re« rj«iieleH,n| .--|| iurlacsAjea |s<fewals] |rflnate<t(aae*J AAjme It¥oudiflBsi|tiae-fl| iTotalVdume Ttvouoh FacttylsaMt) Irfltrsied . rJofcJiType . . Pond Volume at Riser Head |aae-H)'' .Show Pond Table . ;0penTabe ;-fi Use Tide Gale? ' 4/15/2011 : 2:16PM Figure 2. Screen Capture of the Rain Garden Input and Infiltration Output •R* m 5*** "s™ 4|d (Facility Bottom Elevation (tl) jl iFacility Dimensions sTiench Length <TimchBoltai.W>dri sEllartive Total Depik ^Bottom ^ope Dl iTerch (tell Side Slope • iRiohtSideSfcee ; Materia! Layers for l^elTln^jiHslli) ;L^2Thidaierailtl jjLaiw 3 TmduiHi-l11) linya 3 poiatf - [ajmSltrtitipn •- ivES" "1 iMesmfs^WaiabOii FWefn/hiJ ilrflbaiiwi Reduction F«*» :UseWeHBd Surface A*en iadewsk} sfjfj !Ti^lVolii™irilTtialcd[acft:-«) "352.2S -TotslVol™ Trioughaaeitara&ltl - 0DOS Outlet Structure • HctuHtiphdlt] |2.' RBH Diametetfiil >| f RBtaTjipe IFS Orifice D i em el er Height OMax Number (In) (Ft) (cfs) TienchVolumefltFfeHHeadlaae^j :279 ". PoncHrKleroent foiO _lj ShowPonoToblB fdpwifaBe ;4/15£011 !2:15PM 15 ORDINANCE NO. 5611 Sunset Terrace Study Area Existing Conditions - KCRTS Output IS Area Till Forest 0.00 acres Till Pasture 0.00 acres Till Grass 2.90 acres Outwash Forest 0.00 acres Outwash Pasture 0.00 acres Outwash Grass 0.00 acres Wetland 0.00 acres Impervious; 0.00 acres Total 2.90 acres Scale Factor: 1.00 Hourly Historic Time Series: RF1-exj Compute Time Series ] Modify User Input File for computed Time Series [.TSF] Flow Frequency Analysis Time Series File:rfl-ex.tsf Project Location:Sea-Tac —Annual Peak Flow Rates— Flow Rate Rank Time of Peak (CFS) (CFS) 0.196 15 2/16/49 21:00 0.533 1 3/03/50 16:00 0.259 8 2/09/51 2:00 0.119 34 1/30/52 8:00 0.090 39 3/24/53 15:00 0.155 21 12/19/53 19:00 0.195 16 2/07/55 17:00 0.201 14 12/20/55 17:00 0.220 12 12/09/56 14:00 0.143 27 12/25/57 16:00 LogPearson III Coefficients Mean= -0.795 StdDev= 0.226 Skew= 0.298 Flow Frequency Analysis --Peaks- - Rank Return Prob Period 0.533 1 80.57 0.988 0.522 2 28.92 0.965 0.431 3 17.63 0.943 0.363 4 12.67 0.921 0.329 5 9.89 0.899 0.270 6 8.12 0.877 0.266 7 6.88 0.855 0.259 8 5.97 0.832 0.238 9 5.27 0.810 0.232 10 4.72 0.788 ORDINANCE NO. 5611 0.1Q8 37 1/26/59 20:00 0.220 11 11/20/59 21:00 0.139 29 2/14/6121:00 0.081 41 11/22/61 2:00 0.146 25 12/15/62 2:00 0.151 22 12/31/63 23:00 0.112 35 12/21/64 4:00 0.132 32 1/05/66 16:00 0.232 10 1/19/67 14:00 0.172 18 8/24/68 16:00 0.132 33 12/03/68 16:00 0.133 30 1/13/70 22:00 0.148 24 12/06/70 8:00 0.329 5 2/27/72 7:00 0.111 36 1/13/73 2:00 0.165 19 11/28/73 9:00 0.270 6 12/26/74 23:00 0.144 26 12/02/75 20:00 0.054 45 8/26/77 2:00 0.158 20 9/22/78 19:00 0.067 44 11/19/78 0:00 0.215 13 12/14/79 21:00 0.177 17 11/21/80 11:00 0.363 4 10/06/8115:00 0.143 28 1/05/83 8:00 0.150 23 3/15/84 20:00 0.073 42 6/06/85 23:00 0.266 7 1/18/86 16:00 0.238 9 11/24/86 3:00 0.090 40 1/14/88 12:00 0.068 43 11/05/88 14:00 0.522 2 1/09/90 6:00 0.431 3 11/24/90 8:00 0.133 31 1/27/92 15:00 0.101 38 3/22/93 22:00 Computed Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks Computed Peaks 0.220 11 4.27 0.766 0.220 12 3.90 0.744 0.215 13 3.59 0.722 0.201 14 3.33 0.699 0.196 15 3.10 0.677 0.195 16 2.90 0.655 0.177 17 2.72 0.633 0.172 18 2.57 0.611 0.165 19 2.43 0.589 0.158 20 2.31 0.566 0.155 21 2.19 0.544 0.151 22 2.09 0.522 0.150 23 2.00 0.500 0.148 24 1.92 0.478 0.146 25 1.84 0.456 0.144 26 1.77 0.434 0.143 27 1.70 0.411 0.143 28 1.64 0.389 0.139 29 1.58 0.367 0.133 30 1.53 0.345 0.133 31 1.48 0.323 0.132 32 1.43 0.301 0.132 33 1.39 0.278 0.119 34 1.34 0.256 0.112 35 1.31 0.234 0.111 36 1.27 0.212 0.108 37 1.23 0.190 0.101 38 1.20 0.168 0.090 39 1.17 0.145 0.090 40 1.14 0.123 0.081 41 1.11 0.101 0.073 42 1.09 0.079 0.068 43 1.06 0.057 0.067 44 1.04 0.035 0.054 45 1.01 0.012 0.601 100.00 0.990 0.506 50.00 0.980 0.419 25.00 0.960 0.317 10.00 0.900 0.297 8.00 0.875 0.246 5.00 0.800 0.156 2.00 0.500 0.107 1.30 0.231 ORDINANCE NO. 5611 Appendix D2 - Proposed Conveyance System ORDINANCE NO. 5611 Figure 1. Node ID and Pipe ID •: Be £e=r Vew ytvout 2=B fclsc fctep - D E^y a? X W \ 4< ® H 4L Li 2 + SI?: f*: •Pic^osec Frefered Alt Figure 2. CB Rim Elevations and Pipe Sizes •-•g Cen-,-e¥anc=_RrTSlTest I PROTOTYPE - 4: w Jte •••i^FroposadPfsfe limited 3BO.OO0 ft 32U.270 ft f" . 36»,Dian? 1 ORDINANCE NO. 5611 Figure 3. HGL at CB and 25-ycar Peak Flow Rate Ble Bfl Vrev* LSVOtrt SSTS !®c Ssip laraa : - S- Copv6var,ca_FirfstTsi ft K Readies : 12 Rotes, 11 RrixfriB . • :FTcyoseG Prefaid} Al 2 ORDINANCE NO. 5611 History Cleared: 13:26:05 Friday, April 15,2011 ROUTEHYD [] THRU [Proposed Preferred Alt] USING TYPEIA AND [25 year] NOTZERO RELATIVE SCS/SBUH Reach ; Area Flow Full Q ID (ac) (cfs) (cfs) Full | nDepth ratio I (ft) P-006 19.9000 8.9390 10.8248 0.83 ! 1.0389 P-007 16.9000 8.3385 12.518] 0.67 \ 1.1929 P-011 50.0000 24.4783 50.9399 ! 0.48 ! 0.9771 P-011A 66.6000 34.9215 51.0254 0.68 1.2144 P-012 18.0300 8.7961 11.5595 0.76 0.9789 P-001 44.4800 20.6655 28.6632 0.72 \ 1.2573 P-009 32.7200 18.2062 22.6394 0.80 1.3579 P-01A 77.2000 38.8614 44.5548 0.87 1.8069 P-004 113.6500 55.3268 88 7341 0.62 ' 1.7157 P-003 135.3700 61.7918 110.07 0.56 1.3400 P-005 211.2600 101.89 99.6277 1.02 Size 18" Diam 24" Diam 24" Diam 24" Diam 18" Diam 24" Diam 24" Diam 30" Diam 36" Diam 30" Diam 30" Diam nVel | fVel i CBasin / (ft/s) (ft/s) Hyd 6.8445 6.1256 6 4.2671 3.9846 |7 16.0524 I 16.2147 111 17.4940 16.2419 13 7.2011 6 5413 12 9.9367 ! 9.1238 II 8.0167 7.2064 9 10.2289 9.0766 I 13.2388 ! 12.5533 4 23.0632 22.4225 13 20.7577 ! 20.2960 ;!5 3 ORDINANCE NO. 5611 From i To i Rch Loss t App i Bend Junct Loss HW Loss Elev s Max El Node Node (ft) (ft) (ft) (ft) (It) (ft) !: 258.5000 No approach losses at node N-003 because inverts and/or crowns are offset. N-005 Outfall 282.2148 282.2148 ! 284.5200 N-011A N-005 321.0049 0.9427 0.1312 320.1934 320.9600 No approach losses at node N-006 because inverts and/or crowns are offset. N-011 N-011A 333.5197 333.5197 335.3100 N-006 N-011 336.8504 336.8504 340.0000 N-007 N-011 335.9533 335.9533 367.6300 No approach losses at node N-004 because inverts and/or crowns are offset. N-003 N-005 327.1708 327.1708 328.2700 N-004 N-003 343.9864 0.9732 0.0055 0.1666 343.1853 350.7800 1 N-012 1 N-004 ! 377.8257 ) 1 !i 377.8257 I 380.0000 N-01A N-004 353.1676 0.6719 0.8655 0.3412 353.7023 355.0000 N-001 N-01A 372.7299 372.7299 380.3300 N-009 N-01A 364.1122 364.1122 366.6600 Layout Report: Proposed Preferred Alt Event Precip (in) 2 year 2.0000 10 year 3.0000 25 year 3.5000 100 year 4.0000 4 ORDINANCE NO. 5611 Reach Records Record Id: P-001 Section Shape: Circular Uniform Flow Method: Manning's (Coefficient: .lO.0120 Travel Time Translation Contributing 11 yd Routing Method: DnNode Material Ent Losses Length Up Invert N-01A iUpNode Cone-Spun Size [Groove End w/Headwall 1470.0000 ft Slope 1370.0000 ft Dn Invert Conduit Constraints Min Vel Max Vel Min Slope Max Slope Min Cover 2.00 ft/s 15.00 ft/s 0.50% 2.00% 0.0000 ft 350.0000 I t Drop across Mil i\Jp Invert Match inverts. 3.00 ft Ex/Tnfil Rate Dn Invert N-001 24" Diam 1.36% 350.0000 ft 0.0000 in/hr 370.0000 ft Record Id: P-003 Section Shape: Circular Uniform Flow Method: Manning's Coefficient: [Routing Method: DnNode Material tEnt Losses Length Up Invert Travel Time Translation Contributing Hyd N-005 IUpNode Cone-Spun Size (iroove End w/Headwall 750.0000 ft Slope 320.7700 ft Dn Invert Conduit Constraints Min Vel Max Vel Min Slope Max Slope Min Cover i: 2.00 ft/s 15.00 ft/s 0.50% 2.00% 3.00 ft Drop across MH 0.0000 ft Ex/Infil Rate Up Invert 1275.0000 ft Dn Invert Match inverts. 0.0120 •N-003 30" Diam 6.10% 275.0000 ft 0.0000 in/hr '320.7700 ft ORDINANCE NO. 5611 Record Id: P-004 [Section Shape: Circular Uniform Flow Method: Manning's Coefficient: 0.0120 Routing Method: Travel Time Translation Contributing Hyd : ! DnNode Materia] Ent Losses Length Up Tnvert N-003 UpNode Cone-Spun Size Groove End w/Headwall 770.0000 ft Slope 340.00()0fl" Dn Invert Conduit Constraints i Min Vel Max Vel Min Slope Max Slope Min Cover 2.00 ft/s 15.00 ft/s 0.50% 2.00% 3.00 ft Drop across MH Up Invert Match inverts. Record Id: P-005 0.0000 ft 328.4500 ft Ex/Infil Rate Dn Invert N-004 36" Diam : 1.50% 328.4500 ft 0.0000 in/hr 340.0000 ft Section Shape: Circular Uniform Flow Method: (Manning's Coefficient: [Routing Method: (DnNode [Material (Ent Losses [Length Up Invert Travel Time Translation Contributing Hyd Outfall IUpNode Cone-Spun Size Groove End w/Headwall 300.0000 ft Slope 271.0000 ft Dn Invert Conduit Constraints Min Vel Max Vel Min Slope Max Slope Min Cover 2.00 ft/s 15.00 ft/s 0.50% 2.00%; 3.00 ft Ex/Infil Rate Drop across MH Up Invert Match inverts. 0.0000 ft 256.0000 ft Dn Invert 0.0120 N-005 30" Diam 5.00%; 256.0000 ft 0.0000 in/hr 271.0000 ft ORDINANCE NO. 5611 Record Id: P-006 Section Shape: Circular Uniform Flow Method: Manning's Coefficient: Routing Method: DnNode Material Ent Losses Length Up Invert i Travel Time Translation Contributing Hyd : iN-011 IUpNode Cone-Spun Size Groove End w/Headwall 1450.0000 ft Slope 1335.0000 ft Dn Invert Conduit Constraints iMin Vel iMax Vel Min Slope (Max Slope iMin Cover 2.00 ft/s 15.00 ft/s 0.50% 2.007c Drop across MH sUp Invert Match inverts. 0.0000 ft 330.9500 ft 3.00 ft Ex/Infil Rate Dn Invert 0.0120 N-006 18" Diam 0.907c 330.9500 ft 0.0000 in/hr 335.0000 ft Record Id: P-007 Section Shape: Circular Uniform Flow Method: Manning's [Coefficient: Routing Method: DnNode sMaterial Ent Losses Length Up Invert iTravel Time Translation Contributing Hyd t IN-011 IUpNode Cone-Spun Size sGroove End w/Headwall 12000.0000 ft Slope 332.6300 ft Dn Invert Conduit Constraints Min Vel iMax Vel iMin Slope iMax Slope iMin Cover 2.00 ft/s 15.00 ft/s 0.50% 2.007c 3.00 ft Drop across MH 0.0000 ft Hx/lnlil Rate Up Invert 1327.4400 ft Dn Invert Match inverts. 0.0120 1N-007 24" Diam 0.26%: 327.4400 ft 0.0000 in/hr 332.6300 ft ORDINANCE NO. 5611 Record Id: P-009 [Section Shape: Circular Uniform Flow Method: [Manning's Coefficient: [Routing Method: iDnNode Material Ent Losses [Length Up Invert [Travel Time Translation Contributing Hyd N-01A UpNode Cone-Spun [Size [Groove End w/Headwall 1820.0000 ft (Slope 361.6600 ft Dn Invert i Conduit Constraints Min Vel Max Vel Min Slope Max Slope Min Cover 2.00 ft/s 15.00 ft/s 0.50% 2.00%- Drop across MH [Up Invert [Match inverts. 0.0000 ft 354.7000 ft 3.00 ft I Ex/Infil Rate Dn Invert 0.0120 N-009 24" Diam 0.85% 354.7000 ft 0.0000 in/hr 361.6600 ft Record Id: P-011 [Section Shape: [Circular Uniform Flow Method: Manning's [Routing Method: Coefficient: [0.0120 Travel Time Translation Contributing Hyd •> iDnNode Material Ent Losses Length [Up Invert N-011 A IUpNode Cone-Spun Size Groove End w/Headwall 1350.000011 Slope 330.3100 ft Dn Invert Conduit Constraints Min Vel Max Vel Min Slope Max Slope Min Cover 2.00 ft/s 15.00 ft/s 0.50% 2.00% 3.00 ft Drop across MH 0.0000 ft Ex/Infil Rate Up Invert 315.2700 ft I Dn Invert Match inverts. N-011 24" Diam 4.30% 315.2700 ft 0.0000 in/hr 330.3100 ft ORDINANCE NO. 5611 Record Id: P-011A [Section Shape: Circular [Uniform Flow Method: [Manning's [Coefficient: [Routing Method: DnNode [Material iEnt Losses [Length Up Invert Travel Time Translation Contributing Hyd (N-005 (UpNode sConc-Spun [Size Groove End w/Headwall 1950.0000 ft (Slope (315.9600 ft Dn Invert [ i Conduit Constraints Min Vel Max Vel Min Slope Max Slope Min Cover 2.00 ft/s 15.00 ft/s 0.50% 2.00% 3.00 ft Drop across MH 0.0000 ft Lx/Infil Rate (Up Invert (275.0000 ft Dn Invert (Match inverts. 0 0120 N-011A 24" Diam 4.31 % 275.0000 ft 0.0000 in/hr 315.9600 ft Record Id: P-012 Section Shape: [Circular [Uniform Flow Method: -Manning's [Coefficient: [Routing Method: IDnNode [Material [Ent Losses [Length Up Invert Travel Time Translation Contributing Hyd (N-004 (UpNode •Cone-Spun [Size Groove End w/Headwall (1900.0000 ft (Slope (376.0000 ft (Dn Invert Conduit Constraints Min Vel Max Vel Min Slope Max Slope iMin Cover 2.00 ft/s 15.00 ft/s 0.50% 2.00% 3.00 ft (Drop across MH ().()()()() ft iEx/Infil Rate (Up Invert 356.5000 ft Dn Invert Match inverts. 0.0120 N-012 18" Diam 1.03% 356.5000 ft 0.0000 in/hr 376.0000 ft ORDINANCE NO. 5611 Record Id: P-01A [Section Shape: [Circular Uniform Flow Method: [Manning's Coefficient: 0.0120 Routing Method: [Travel Time Translation Contributing I lyd (DnNode [N-004 (UpNode IN-01A [Material ;Conc-Spun Size [30" Diam [Ent Losses /Groove End w/Headwall (Length (950.0000 ft (Slope 11.00% Up Invert (349.5000 ft Dn Invert 340.0000 ft si Conduit Constraints [;Min Vel iMax Vel Min Slope [Max Slope Min Cover i 2.00 ft/s 15.00 ft/s 0.50%; 2.00%; 3.00 ft Drop across MH 10.0000 ft iEx/Infil Rate iO.OOOO in/hr Up Invert 1340.0000 ft Dn Invert 349.5000 ft (Match inverts. ORDINANCE NO. 5611 Node Records Record Id: N-001 Descrip: [Node Start El. 370.0000 ft Classification Manhole Ent Ke [Groove End w/Headwall (ke: Catch 11.5000 ft Condition Existing Increment 0.10 It \ Max El. 380.3300 ft Structure Type CB-TYPE 1-48 :0.20) Channelization Curved or Deflector ; (Bottom Area 119.6350 sf | Record Id: N-003 Descrip: Node Increment 0.10 ft Start El. 320.7700 ft Max El. 328.2700 ft Classification Manhole Structure Type CB-TYPE 1-48 Ent Ke Groove End w/Headwall (ke=0.20) Channelization Curved or Deflector Catch 1.5000 ft (Bottom Area 19.6350 sf Condition [Existing Record Id: N-004 Descrip: [Node Increment 0.10 ft Start El. 1340.0000 ft (Max El. (350.7800 ft Classification Manhole (Structure Type (CB-TYPE 1-48 Ent Ke [Groove End w/Headwall (ke=0.20) Channelization Curved or Deflector Catch 1.5000 ft (Bottom Area 19.6350 sf Condition Existing Record Id: N-005 Descrip: Node Increment 0.10 ft Start El. 271.0000 ft (Max El. (284.5200 ft Classification Manhole Structure Type CB-TYPb 1-48 Ent Ke Groove End w/Headwall (ke=0.20) Channelization Curved or Deflector Catch (1.5000 ft [Bottom Area (19.6350 sf Condition Existing ORDINANCE NO. 5611 Record Id: N-006 [Descrip: Wide Increment [0.10ft (Start El. (335.0000 ft (Max El. (340.0000 ft Classification Manhole [Structure Type CB-TYPE 1-48 Ent Ke Groove End w/Headwall (ke=0.20) Channelization Curved or Deflector (Catch (1.5000 ft (Bottom Area 119.6350 sf Condition [Existing Record Id: N-007 [Descrip: [Node [Increment 0.10ft Start El. 1332.6300 ft Max El. 367.6300 ft Classification Manhole Structure Type CB-TYPE 1-48 [Ent Ke [Groove End w/Headwall (ke=0.20) Channelization Curved or Deflector, Catch 1.5000 it Bottom Area 19.6350 sf Condition Existing Record Id: N-009 Descrip: [Node [Increment 0.10 Ii Start El. 361.6600 ft Max El. 366.6600 ft Classification Manhole Structure Type CB-TYPE 1-48 Ent Ke [Groove End w/Headwall (ke=0.20) Channelization Curved or Deflector (Catch 11.5000 ft (Bottom Area I1) 6>5<KI Condition Existing Record Id: N-011 Descrip: Node Increment [0.10 ft Start El. 330.3100 ft Max El. 335.3100 ft Classification (Manhole [Structure Type CB-TYPE 1-48 Ent Ke (Groove End w/Headwall (ke=0.20) Channelization Curved or Deflector i Catch (1.5000 ft Bottom Area 119.6350 sf Condition [Existing ORDINANCE NO. 5611 Record Id: N-011A Descrip: [Prototype Record (Start El. 1315.9600 ft Classification Manhole lint Ke (Groove End w/Headwall (ke: (Catch 11.5000 ft ^Condition Existing [Increment 0.10 ft Max El. ,320.9600 ft Structure Type CB-TYPE 1-48 =0.20) Channelization Curved or Deflector; Bottom Area 19.6350 sf | Record Id: N-012 [Descrip: Node Start El. 376.0000 ft Classification Manhole Ent Ke Groove End w/Headwall (kc= Catch 1.5000 ft Condition Existing [Increment 0.10 ft Max El. 380.0000 ft Structure Type CB-TYPE 1-48 |.20) Channelization Curved or Deflector (Bottom Area i 19.6350 sf Record Id: N-01A [Descrip: [Node Start El. 349.5000 ft Classification Manhole Ent Ke [Groove End w/Headwall (ke=l Catch 11.5000 ft Condition [Existing [Increment 0.10 ft Max El. (355.0000 ft Structure Type CB-TYPE 1-48 '.20) Channelization Curved or Deflector Bottom Area 19.6350 sf Record Id: Outfall Descrip: Prototype Record Increment 0.10 ft | Start El. 258.0000 ft Max El. 270.0000 ft 1 U-;w.:..:.._.-v^v :._J i...^,...^,.,..^.,,.™^....^....^...,™:!:...^: :...v..v...4,v.,,_:.. .. .^ \ Dummy Type Node | ORDINANCE NO. 5611 1 Event Summary Event Peak Q (cfs) Peak T (hrs) Hyd Vol (acft) Area (ac) Method Raintvpe 2 year 10.4257 10 year 17.1903 25 year 20.6655 100 yeari 24.1797 Record Id: 1 Design Method iHyd Intv Pervious Area (AMC 2) Pervious CN [Pervious TC 8.17 8.17 8.17 8.17 5.3837 44.4800 SBUH TYPEIA 8.7917 44.4800 SBUH TYPEIA 10.5397 44.4800 SBUH TYPEIA 12.306J 44.4800 SBUH TYPEIA Rainfall type [Peaking Factor (Abstraction Coeff IDCTA DC CN SBUH 10.00 min 12.87 ac 82.29 34.79 min Pervious CN Calc Description Open spaces, lawns,parks (>75% grass) Open spaces, lawns,parks (>75% grass) Wood/forest land (young 2nd growth/brush) Pervious Composited CN (AMC 2) SubArea 6.09 ac 5.98 ac 0.80 ac TYPEIA 484.00 0.20 31.61 ac 98.00 34.79 min Sub cn 80.00 86.00 72.00 82.29 Pervious TC Calc ! Type i Sheet: [Shallow Description [Short prairie grass and lawns.: 0.15 [Short grass, pasture and lawns (n=0.030) [ Length 250.00 ft 280.00 ft Slope Coeff Misc IT 1.60% 0.1500 2.00 in 28.20 min 4.30% 0.0300 Channel (inlerm) [Concrete pipe (n=0.012) 1350.00 ft 1.40% 0.0120 Pervious TC Directly Connected CN Calc Description Impervious surfaces (pavements, roofs, etc) Impervious surfaces (pavements, roofs, etc) Impervious surfaces (pavements, roofs, etc) DC Composited CN (AMC 2) Directly Connected TC Calc SubArea 6.40 ac 17.36 ac 7.85 ac Type Description [Sheet Short prairie grass and lawns.: 0.15 [Shallow iShort grass, pasture and lawns (n=0.030) [Channel (interm) [Concrete pipe (n=0.012) Directly Connected TC Slope Length 250.00 ft 280.00 ft 4.30% 0.0300 1350.00 ft 1.40% 0.0120 [2.10 min i4.48 min 34.79 min Sub cn "Mill 98.00 98.00 98.00 IT Coeff Misc 1.60% 10.1500 2.00 in 28.2(1 min 2.10 min [4.48 min 34.79min 14 ORDINANCE NO. 5611 2 Event Summary Event Peak Q (els) Peak T (hrs) Hyd Vol (acft) Area (ac) Method Raintype 2 year 3.1630 8.00 1.2966 9.9100 10 year I 5^0572 S 8.00 I 2.0748 I 9.9100 25 year 6.0178 8.00 \\ 2.4707 1 9.9100 100 year 6.9847 8.00 2.8694 9.9100 SBUH TYPEIA SBUH TYPIiJA SBUH TYPEIA SBUH TYPHI A Record Id: 2 Design Method Hyd Intv Pervious Area (AMC 2) Pervious CN Pervious TC SBUH 10.00 min 1.67 ac 80.00 17.32 min Rainfall type Peaking Factor [Abstraction Coeff DCIA DC CN DC TC Pervious CN Calc i Description i Open spaces, lawnsjparks (>75% grass) J Pervious Composited CN (AMC 2) Pervious TC Calc s Type Description Length i Slope {Sheet [Short prairie grass and lawns.: 0.15 1130.00 ft 15.00% [Shallow Paved 11100.00 ft 11.80% Pervious TC i Directly Connected CN Calc i Description Impervious surfaces (pavements, roofs, etc) Impervious surfaces (pavements, roofs, etc) I I >C Composited CN (AMC 2) Directly Connected TC Calc Type Description > Length •; Slope iSheet iShort prairie grass and lawns.: 0.15 [130.00 ft 15.00% [Shallow (Paved I 100.00 ft 11.80% i Directly Connected TC SubArea 1.67 ac Coeff Misc 0.1500 2.00 in 0.0100 SubArea 5.50 ac 2.74 ac Coeff 0.1500 0.0100 Misc 12.00 in TYPlilA 484.00 0.20 8.24 ac 98.00 17.32 min Sub cn 80.00 80.00 IT 10.60 min 6.72 min 17.32 min Sub cn •>MH) 98.00 98.00 TT 10.60 min 6.72 min I 17.32min 15 ORDINANCE NO. 5611 3 Event Summary Event Peak Q (cfs) Peak T (hrs) Hyd Vol (acft) Area (ac) Method Raintype 2 year 2.2713 10 year 4.974J 25 year 6.4650 100 year 8.0129 Record l<l: J* Design Method Hyd Intv Pervious Area (AMC 2) Pervious CN Pervious TC 8.17 8.17 8.17 8.17 1.5895 3.0386 3.8171 4.6183 21.7200 21.7200 21.7200 21.7200 SBUH SBUH SBUH TYPHI A TYPHI A TYPHIA SBUH 10.00 min 18.82 ac 83.92 43.73 min SBUH TYPHI A Rainfall type Peaking Factor [Abstraction Coeff IDCIA Slope 0.50% 2.30% Coeff 0.1500 0.0300 DCCN DC TC Pervious CN Calc Description SubArea Open spaces, lawns,parks (>75% grass) \ 6.51 ac i Open spaces, lawns,parks (>75% grass) 12.31 ac Pervious Composited CN (AMC 2) Pervious TC Calc [ Type Description Length [Sheet [Short prairie grass and lawns.: 0.15 200.00 ft [Shallow iShort grass, pasture and lawns (n=0.030) 600.00 ft Pervious TC Directly Connected CN Calc Description SubArea Impervious surfaces (pavements, roofs, etc) i 0.65 ac s Impervious surfaces (pavements, roofs, etc) \ 1.91 ac s Impervious surfaces (pavements, roofs, etc) i 0.34 ac DC Composited CN (AMC 2) Directly Connected TC Calc Type Description Length Slope Coeff Sheet (Short prairie grass and lawns.: 0.15 S200.00ft 10.50% (0.1500 (Shallow (Short grass, pasture and lawns (n=0.030) 1600.00 ft (2.30% 10.0300 i Directly Connected TC Misc 2.00 in Misc 2.00 in TYPHI A 484.00 0.20 2.90 ac 98.00 43.73 min Sub cn 80.00 86.00 83.92 TT i37.57 min [6.16 min ( 43.73 min Sub cn 98.00 98.00 98.00 98.00 TT 37.57 min i6.16 min 43.73min 16 ORDINANCE NO. 5611 4 Event Summary Event Peak Q (cfs) Peak T (hrs) Hyd Vol (acft) Area (ac) Method Raintype 2 year 3.8254 10 year 6.3643 25 year 7.6693 100 year 8.9888 Record Id: 4 Design Method Hyd Intv Pervious Area (AMC 2) Pervious CN Pervious TC 8.17 8.17 8.17 8.17 2.2405 3.6609 4.3885 5.1233 SBUH 10.00 min 5.54 ac 83.68 40.31 min 18.4200 SBUH TYPEIA 18.4200 SBUH TYPEIA 18.4200 SBUH TYPEIA 18.4200 SBUH TYPEIA Rainfall type Peaking Factor Abstraction Coeff D( I \ DC CN DC TC Pervious CN Calc Description ! Open spaces, lawns,parks (>75% grass) i Open spaces, lawns,parks (>75% grass) i Pervious Composited CN (AMC 2) Pervious TC Calc Type Description Length Slope Sheet Short prairie grass and lawns.: 0.15 280.00 ft 1.40% Shallow Paved 11300.00 ft 11.90% Pervious TC Directly Connected CN Calc Description s Impervious surfaces (pavements, roofs, etc) • Impervious surfaces (pavements, roofs, etc) f Impervious surfaces (pavements, roofs, etc) DC Composited CN (AMC 2) Directly Connected TC Calc i Type i Description Length (Sheet (Cultivated Soil w/ residue cover (s>20%)..: 0.17 1280.00 ft /Shallow [Short grass, pasture and lawns (n=0.030) [1300.00 ft i Directlv Connected TC SubArea 3.40 ac 2.14 ac i Coeff Misc 0.1500 2.00 in 0.0100 SubArea 5.10 ac 4.92 ac 2.86 ac TYPHI A 484.00 0.20 12.88 ac 98.00 50.70 min Sub cn 86.00 80.00 83.68 TT 132.57 min [7.73 min ) 40.31 min Sub cn 98.00 98.00 98.00 98.00 Slope Coeff Misc TT 1.40% 0.1700 2.00 in 36.01 min 1.90% 0.0300 14.69 min I 50.70min 17 ORDINANCE NO. 5611 5 Event Summary Event Peak Q (cfs) Peak T (hrs) Hyd Vol (acft) Area (ac) Method Raintype 2 year 2.8289 10 year 4.6317 25 year 5.5558 100 year 6.4899 Record Id: 5 Design Method Hyd Intv [Pervious Area (AMC 2) Pervious CN Pervious TC 8.00 8.00 8.00 8.00 1.1387 1.8519 2.2174 2.5865 SBUH 10.00 rain 2.45 ac 81.44 15.25 min 9.2900 SBUH TYPE 1A 9.2900 SBUH TYPEIA 9.2900 SBUH TYPEIA 9.2900 SBUH TYPEIA Rainfall type Peaking Factor Abstraction Coeff DCIA "" DC CN DC TC "_ Pervious CN Calc i Description /! Open spaces, lawns,parks (>75% grass) ! / Open spaces, lawns,parks (>75% grass) s Pervious Composited CN (AMC 2) Pervious TC Calc i Type Description Length s Slope /Sheet /Short prairie grass and lawns.: 0.15 1200.00 ft 15.50% Shallow ./Short grass, pasture and lawns (n=0.030) 1250.00 ft (20.80% i Pervious TC Directly Connected CN Calc Description • Impervious surfaces (pavements, roofs, etc) \ s Impervious surfaces (pavements, roofs, etc) i i Impervious surfaces (pavements, roofs, etc) s ! DC Composited CN (AMC 2) Directly Connected TC Calc ! Type Description i Length ; Slope (Sheet (Short prairie grass and lawns.: 0.15 (200.00 ft ;5.50% [Shallow : (Short grass, pasture and lawns (n=0.030) (250.00 ft (20.80% Directly Connected TC SubArea 0.59 ac 1.86 ac Coeff 0.1500 0.0300 Misc 2.00 in SubArea 2.37 ac 0.92 ac 3.55 ac Coeff / Misc 0.1500 2.00 in (0.0300 I TYPEIA 484.00 0.20 6.84 ac 98.00 15.25 min Sub cn 86.00 80.00 81.44 TT (14.40 min (0.85 min i 15.25 min Sub cn 98.00 98.00 98.00 98.00 TT 114.40 min (0.85 min / 15.25min 18 ORDINANCE NO. 5611 6 Event Summary Event Peak Q (cfs) Peak T (hrs) Hyd Vol (acft) Area (ac) Method Raintype 2 year 4.7747 10 year 7.5487 25 year 8.9390 100 year 10.3301 Record Id: 6 Design Method Hyd Intv Pervious Area (AMC 2) Pervious CN Pervious TC 8.17 8.17 8.17 8.17 2.7704 4.3851 5.1998 6.0172 19.9000 19.9000 19.9000 19.9000 SBUH 10.00 min 2.23 ac 86.00 52.81 min SBUH TYPHI A SBUH TYPHI A SBUH TYPHI A SBUH TYPHI A [Rainfall type Peaking Factor /Abstraction Coeff IDCIA DC CN DC TC Pervious CN Calc Description SubArea ; Open spaces, lawns,parks (>75% grass) \ 2.23 ac Pervious Composited CN (AMC 2) Pervious TC Calc Type Description s Length Slope s Coeff i Misc Sheet Short prairie grass and lawns.: 0.15 300.00 ft 0.70% 0.1500 2.00 in (Shallow /Short grass, pasture and lawns (n=0.030) 150.00 ft 10.90% 10.0300 I Pervious TC Directly Connected CN Calc Description SubArea i Impervious surfaces (pavements, roofs, etc) i 13.90 ac s \ Impervious surfaces (pavements, roofs, etc) i 3.77 ac i DC Composited CN (AMC 2) i I Directly Connected TC Calc Type Description Length ( Slope Coeff Misc /Sheet (Short prairie grass and lawns.: 0.15 1300.00 ft 10.70% 10.1500 .12.00 in (Shallow Short grass, pasture and lawns (n=0.030) (450.00 ft 10.90% 10.0300 1 i Directly Connected TC TYPHI A 484.00 0.20 17.67 ac 98.00 52.81 min Sub cn 86.00 86.00 TT 45.42 min 7.39 min 52.81 min Sub cn 98.00 98.00 98.00 TT 145.42 min 17.39 min I 52.81 min 19 ORDINANCE NO. 5611 7 Event Summary Event Peak Q (cfs) Peak T (hrs) Hyd Vol (acft) Area (ac) Method Raintype 2 year 4.2411 10 year 6.9561 25 year 8.3385 100 year 9.7299 Record Id: 7 Design Method Hyd Intv Pervious Area (AMC 2) Pervious CN Pervious TC 8.17 8.17 8.17 8.17 2.1148 3.4397 4.1155 4.7966 16.9000 16.9000 16.9000 16.9000 SBUH 10.00 min 4.98 ac 86.00 32.36 min SBUH TYPHI A SBUH TYPHI A SBUH TYPHI A SBUH TYPHI A Rainfall type Peaking Factor Abstraction Coeff DCIA DC CN DC TC Pervious CN Calc Description SubArea i s Open spaces, lawns,parks (>75% grass) \ 4.98 ac \ i Pervious Composited CN (AMC 2) Pervious TC Calc Type Description s Length s Slope s Coelf Misc iSheet iShort prairie grass and lawns.: 0.15 1250.00 ft 11.60% 10.1500 12.00 in [Shallow (Short grass, pasture and lawns (n=0.030) 1520.00 ft B.80% 10.0300 I Pervious TC i Directly Connected CN Calc i Description i SubArea i ! Impervious surfaces (pavements, roofs, etc) i 9.45 ac s Impervious surfaces (pavements, roofs, etc) \ 2.47 ac DC Composited CN (AMC 2) i Directly Connected TC Calc ; Type Description Length s Slope s Coeff i Misc ISheet (Short prairie grass and lawns.: 0.15 1250.00 ft 11.60% 10.1500 12.00 in [Shallow (Short grass, pasture and lawns (n=0.030) 1520.00 ft B.80% 10.0300 1 Directly Connected TC TYPHI A 484.00 0.20 11.92ac 98.00 32.36 min Sub cn 86.00 86.00 TT 128.20 min 4.15 min \ 32.36 min Sub cn 98.00 98.00 98.00 IT 128.20 min (4.15 min i 32.36min 20 ORDINANCE NO. 5611 8.17 8.17 8.00 8.00 4.3985 7.0229 8.3518 9.6872 9 Event Summary Event Peak Q (cfs) Peak T (hrs) Hyd Vol (acft) Area (ac) Method Raintype I 2 year ! 9.6179 10 year 15.3232 25 year 18.2062 100 year 21.1026 Record Id: 9 Design Method Hyd Intv Pervious Area (AMC 2) Pervious CN Pervious TC SBUH 10.00 min 5.69 ac 85.98 25.17 min 32.7200 SBUH TYPHI A 32.7200 SBUH TYPEIA 32 7200 SBUH TYPEIA 32.7200 SBUH TYPHI A Rainfall type Peaking Factor Abstraction Coeff (DCIA DCCN """ DC TC Pervious CN Calc Description Open spaces, lawns,parks (>75% grass) Open spaces, lawns,parks (>75% grass) Pervious Composited CN (AMC 2) SubArea 5.67 ac 0.02 ac TYPEIA 484.00 0.20 27.03 ac 98.00 25.17 min Sub cn 86.00 80.00 85.98 Type Pervious TC Calc Description i Length Slope ( Coelf Misc TT Sheet Shallow i Shallow Short prairie grass and lawns.: 0.15 [Short grass, pasture and lawns (n=0.030) Paved 200.00 ft 2.50% 0.1500 2.00 in 19.74 min Channel (interm) [Concrete pipe (n=().() 12) 130.00 ft 2.30% 0.0300 600.00 ft 2.70% 0.0100 400.00 ft 2.00% 0.0120 Pervious TC Directly Connected CN Calc Description Impervious surfaces (pavements, roofs, etc) Impervious surfaces (pavements, roofs, etc) DC Composited CN (AMC 2) SubArea 18.24 ac 8.79 ac Type iSheet [Shallow [Shallow Short prairie grass and lawns.: 0.15 iShort grass, pasture and lawns (n=0.030) Paved Channel (interm) [Concrete pipe (n=0.012) Direct]v Connected TC Directly Connected TC Calc Description [ Length [ Slope Cocif Misc (200.00 ft 12.50% 10.1500 12.00 in' 130.00 ft 2.30% 0.0300 i600.00ft 2.70% 0.0100 400.00 ft 2.009; 0.0120 I • 1.34 min 2.99 min 1.11 min \ 25.17 min Sub cn 98.00 98.00 98.00 TT 19.74 min (1.34 min 2.99 min 1.11 min [ 25.17min 21 ORDINANCE NO. 5611 10 Event Summary Event Peak Q (cfs) Peak T (hrs) Hyd Vol (acft) Area (ac) Method Raintype 2 year 14.2083 ( 10 year \ 24.4884 25 year 29.8801 100 year 35.3817 Record Id: 10 Design Method Hyd Intv Pervious Area (AMC 2) Pervious CN Pervious TC 8.00 8.00 8.00 8.00 5.6225 9.4609 11.4593 13.4918 52.7900 52.7900 52.7900 52.7900 SBUH 10.00 min 22.30 ac 80.89 11.96 min SBUH TYPHI A SBUH TYPHI A SBUH TYPHI A SBUH iTYPEIA Rainfall type iPeaking Factor [Abstraction Coeff IDCIA DC CN DC TC Type i Shallow Channel (interm) ! Channel (interm) i Channel (interm) Pervious CN Calc Description Open spaces, lawns,parks (>75% grass) Open spaces, lawns,parks (>75% grass) Pervious Composited CN (AMC 2) Pervious TC Calc Description Length Paved 1250.00 ft Concrete pipe (n=0.012) 1550.00 ft [Concrete pipe (n=0.012) (550.00 ft (Concrete pipe (n=0.012) 11100.00 ft Pervious TC Slope 2.00% 5.30% 1.50% 0.50% Directly Connected CN Calc Description Impervious surfaces (pavements, roofs, etc) Impervious surfaces (pavements, roofs, etc) Impervious surfaces (pavements, roofs, etc) DC Composited CN (AMC 2) Directlv Connected TC Calc Type [Shallow i Channel (interm) [Channel (interm) Channel (interm) Description Length i Slope (Paved 1250.00 ft 12.00% Concrete pipe (n=().OI2) 11550.00 ft 15.30% (Concrete pipe (n=0.012) 1100.00 ft 10.50% (Concrete pipe (n=0.012) 1550.00 ft 11.50% Directly Connected TC SubArea 19.00 ac 3.30 ac Coeff 0.0100 0.0120 0.0120 0 0120 Misc SubArea 1.39 ac 15.40 ac 13.70 ac Coeff 0.0100 0.0120 0.0120 0.0120 Misc TYPHI A 484.00 0.20 30.49 ac 98.00 11.96 min Sub cn 80.00 86.00 80.89 TT 1.15 min 12.64 min [1.76 min [6.11 min 11.96 min Sub cn 98.00 98.00 98.00 98.00 TT 1.45 min 2.64 min 6.11 min 1.76 min 11.96min 22 ORDINANCE NO. 5611 11 Event Summary Event Peak Q (cfs) Peak T (hrs) Hyd Vol (acft) Area (ac) Method Raintype 8.17 I 1.8753 I! 13.2000 1 SBUH (TYPEIA I 8.17 2.9502 i 13.2000 SBUH TYPHI A 8.17 3.4916 I ^^^^'-p^J^p^g^l 8.17 I 4.0345 Ii 13.2000 SBUH TYPETA1| SBUH Rainfall t\pe 10.00 min [Peaking Factor [Abstraction Coeff 2 year 3.9121 10 year 6.1050 25 year 7.2008 100 year 8.2963 Record Id: 11 Design Method Hyd Intv Pervious Area (AMC 2) Pervious CN Pervious TC 0.79 ac 81.22 31.21 min DCCN I DC TC i Pervious CN Calc Description i SubArea Open spaces, lawns.parks (>75% grass) i 0.16 ac i Open spaces, lawns,parks (>75% grass) 0.63 ac Pervious Composited CN (AMC 2) Pervious TC Calc Type Description i Length ( Slope s Coelf Misc (Sheet (Short prairie grass and lawns.: 0.15 1200.00 ft 11.00% 10.1500 (2.00 in Shallow Paved 350 00 ft 1.10% 0.0100 Pervious TC Directly Connected CN Calc Description i SubArea i Impervious surfaces (pavements, roofs, etc) i 1.31 ac 1 Impervious surfaces (pavements, roofs, etc) s 5.58 ac Impervious surfaces (pavements, roofs, etc) i 5.52 ac I DC Composited CN (AMC 2) Directly Connected TC Calc Type Description Length Slope Coeff i Misc (Sheet (Short prairie grass and lawns.: 0.15 1200.00 ft 1.00% (0.1500 2.00 in [Shallow Paved [350.00 ft il.10% 10.0100 I [ Directly Connected TC TYPEIA 484.00 0.20 12.41 ac 98.00 31.21 min Sub cn 86.00 80.00 81.22 28.47 min 2.74 min [ 31.21 min Sub cn 98.00 98.00 98.00 98.00 TT 28.47 min (2.74 min s 31.21 min 23 ORDINANCE NO. 5611 12 Event Summary Event Peak Q (cts) Peak T (hrs) Hyd Vol (acft) Area (ac) Method Raintype 2 year 4.6749 10 year 7.4137 25 year 8.7961 100 year 10 1844 Record Id: 12 [Design Method Hyd Intv Pervious Area (AMC 2) Pervious CN Pervious TC 8.17 8.17 8.17 8.17 2.4291 18.0300 SBUH TYPEIA 3.8629 18.0300 SBUH TYPEIA 4.5897 18.0300 SBUH TYPEIA 5.3207 18.0300 SBUH TYPEIA SBUH 10.00 min 2.35 ac 80.08 38.55 min Rainfall type [Peaking Factor Abstraction Coeff DCIA DC CN DC TC Type Sheet i Shallow Pervious CN Calc Description Open spaces, lawns,parks (>75% grass) :i Open spaces, lawns,parks (>75% grass) i Pervious Composited CN (AMC 2) Pervious TC Calc Description Length Slope [Short prairie grass and lawns.: 0.15 1300.00 ft 12.00% iShort grass, pasture and lawns (n=0.030) 1500.00 ft 10.80% Pervious TC Directly Connected CN Calc Description Impervious surfaces (pavements, roofs, etc) \ Impervious surfaces (pavements, roofs, etc) \ Impervious surfaces (pavements, roofs, etc) DC Composited CN (AMC 2) SubArea 2.32 ac 0.03 ac Coeff 0.1500 0.0300 Misc 2.00 in SubArea 0.37 ac 2.14 ac 13.17 ac Type Sheet Shallow Directly Connected TC Calc Description Length Slope i Coeff Misc Short prairie grass and lawns.: 0.15 1300.00 ft 12.00% 10.1500 12.00 in iShort grass, pasture and lawns (n=0.030) 1500.00 ft 10.80% S0.0300 1 Directly Connected TC TYPEIA 484.00 0.20 15.68 ac 98.00 38.55 min Sub cn 80.00 86.00 80.08 TT 129.85 min 18.71 min i 38.55 min Sub cn 98.00 98.00 98.00 98.00 TT 129.85 min 18.71 min i 38.55min 24 ORDINANCE NO. 5611 13 Event Summary Event Peak Q (cfs) Peak T (hrs) Hyd Vol (acft) Area (ac) Method Raintype 2 year 6.0184 10 year 9.2869 25 year 10.9081 100 year 12.5236 Record Id: 13 Design Method Hyd Intv Pervious Area (AMC 2) Pervious CN Pervious TC 8.00 8.00 8.00 8.00 2.4544 3.8293 4.5186 5.2082 SBUH 10.00 min 0.00 ac 0.00 18.84 min 16.6000 SBUH TYPEIA 16.6000 SBUH TYPEIA 16.6000 SBUH TYPEIA 16.6000 i SBUH TYPEIA Rainfall type Peaking Factor [Abstraction Coeff DCIA DC CN DC TC ~' Type i Sheet [Shallow Channel (interm) Channel (interm) Pervious TC Calc Description Length [Short prairie grass and lawns.: 0.15 [128.40 ft Paved 165.80 ft ^Concrete pipe (n=0.012) 1847.00 ft Concrete pipe (n=0.012) 1770.00 ft Pervious TC Directly Connected CN Calc Description Impervious surfaces (pavements, roofs, etc) DC Composited CN (AMC 2) Directly Connected TC Calc [ Type iSheet [Shallow [Channel (interm) [Channel (interm) Description Length [Short prairie grass and lawns.: 0.15 128.40 ft (Paved 165.80 ft Concrete pipe (n=0.012) 817.00 ft (Concrete pipe (n=0.012) (1770.00 ft Directly Connected TC Slope Coeff Misc 3.12% 0.1500 2.00 in 2.41% 0.0100 5.87% 0.0120 3.14% 0.0120 SubArea 16.60 ac [ Slope 3.12% 2.41% 5.87% 3.14% Coeff Misc 0.1500 2.00 in 0.0100 0 0120 0.0120 TYPEIA 484.00 0.20 16.60 ac 98.00 18.84 min TT [12.67 min 0.88 min [1.37 min 13.92 min 1 18.84 min Sub cn 98.00 98.00 TT 12.67 min 0.88 min 1.37 min 3.92 min I 18.84min Licensed to: Ch2M Hill - Bellevue, WA 25