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SWP273658(2)
Predesign Report Sunset Area Low-impact Y Development Retrofit Improvements Harrington Avenue NE Green Connections & Sunset Terrace Regional Stormwater Facility Prepared for City of Renton, Washington Prepared by N2MHILL® December 2012 Predesign Report Sunset Area Low-impact 4 Development Retrofit Improvements Harrington Avenue NE Green Connections & Sunset Terrace Regional Stormwater Facility Prepared for City of Renton, Washington 4 � O 38291 �j Prepared by yipt CH2MHILL, 4 December 2012 Contents 1. Project Description ................................................................................................................................. 1 2. Site Conditions........................................................................................................................................ 1 2.1 Existing Site Conditions........................................................................................................................1 2.2 Site Infiltration Suitability....................................................................................................................3 3. Design Criteria ........................................................................................................................................3 4. Proposed Drainage Improvements..........................................................................................................4 4.1 Best Management Practices................................................................................................................4 4.2 Sunset Terrace Regional Stormwater Facility......................................................................................4 4.3 Harrington Avenue NE.........................................................................................................................7 5. Design Analysis.....................................................................................................................................20 5.1 Sunset Terrace Regional Stormwater Facility....................................................................................20 5.2 Harrington Avenue NE.......................................................................................................................21 5.3 Issues for Further Consideration .......................................................................................................22 6. Cost Opinion.........................................................................................................................................23 7. Reference ............................................................................................................................................. 24 Tables 1 Tributary Area to Bioretention Swales on Harrington Avenue NE Green Connections 2 Proposed Bioretention Swale Size 3 Peak flow rates of Existing and Proposed Conditions for the Sunset Terrace Regional Stormwater Facility 4 Treatment Volume and Flow Reduction Percentages from BMPs 5 Opinion of Cost Figures • 1 Sunset Terrace Regional Stormwater Facility layout 2A Harrington Avenue NE—Proposed Layout. NE16th Street to NE 12th Street (North). 2B Harrington Avenue NE- Proposed Layout. NE16th Street to NE 12th Street (South). 3 Harrington Avenue NE - Proposed Layout. NE12th Street to NE 10th Street 4 Harrington Avenue NE- Proposed Layout. Sunset Boulevard NE to NE 9th Street 5A Harrington Avenue NE - Proposed Layout. NE9th Street to NE 7th Street (North) 513 Harrington Avenue NE -Proposed Layout. NE9th Street to NE 7th Street (South) Appendixes Appendix A Tributary Area Maps Appendix B Sunset Terrace Regional Stormwtaer Facility Typical Sections Appendix C Harrington Avenue NE Typical Sections Appendix D WWHM Model Output and Input Appendix E Opinion of Cost Appendix F Comment Resolution Form WBG103012044146SEA I DRFAFT PREDESIGN REPORT COPYRIGHT 2012 BY CH2M HILL ENGINEERS,INC.•COMPANY CONFIDENTIAL Acronyms and Abbreviations ASTM American Society for Testing and Materials Ave Avenue BMP Best Management Practices City City of Renton Ecology Washington State Department of Ecology ft3/s cubic feet per second GIS geographic information system KCSWDM King County Surface Water Design Manual LID low-impact development NEPA National Environmental Policy Act SEPA State Environmental Policy Act mm millimeter PGIS Pollutant generating impervious Surfaces RHA City of Renton Housing Authority RMC Renton Municipal Code Sea-Tac Seattle-Tacoma USDA United States Department of Agriculture WWHM Western Washington Hydrological Model PREDESIGN REPORT Sunset Area Low-Impact Development Retrofit Improvements 1 . Project Description The City of Renton completed and adopted the Draft Sunset Area Community Planned Action NEPA/SEPA Environmental Impact Statement Draft(City of Renton, 2010a) in 2010, which included the adoption of the Sunset Area Surface Water Master Plan (City of Renton, 2011).The Sunset Area Surface Water Master Plan identifies areas where green connection improvements could be made at locations that fit with existing and planned future land use in the area and the construction of a regional stormwater facility.These improvements will retrofit existing storm systems in the area to reduce the quantity and improve the quality of stormwater runoff from the existing and future land use within the Sunset Community Plan Area,which discharge to Johns Creek and Lake Washington. While providing enhanced treatment per Ecology standards,the proposed practices also provide significant reduction of fecal coliform,typical average reductions of up to 90 percent(Rusciano, 2007),which is a significant contributor to water quality issues at Johns Creek and Coulon Park in Lake Washington. The green connection street stormwater improvements consist of constructing bioretention swales (AKA rain gardens) and pervious concrete sidewalks primarily along Harrington Avenue NE.The regional stormwater facility consists of constructing an infiltration flow control facility with a rain garden stormwater facility providing water quality treatment. This predesign report summarizes the conceptual design for two Sunset Area Low-Impact Development Retrofit Projects: • Sunset Terrace Regional Stormwater Facility • Harrington Avenue NE, between NE 16th Street to NE 7th Street This report includes the predesign layout, design assumptions, and results of the analysis.The information will be used as a basis for final design. 2. - Site Conditions 2.1 Existing Site Conditions The project site is located in the Sunset Area in the City of Renton and consists of mixed single-family and multifamily residential and commercial neighborhoods with adjacent schools and public lands.The terrain is relative flat,with a less than 5 percent slope toward the south. Both project areas drain to Johns Creek and Lake Washington. 2.1.1 Sunset Terrace Regional Stormwater Facility The proposed regional stormwater facility will be co-located with a proposed City of Renton park,which is located west of Sunset Boulevard between NE loth Street and Sunset Court.This site is currently owned by Renton Housing Authority(RHA) and occupied by multifamily housing units.The existing housing will be relocated by Spring 2014, and the site will be converted into a public park. The surface water runoff from this site generally drains overland to the southwest and is collected in existing storm drains in Harrington Avenue NE. Harrington Avenue NE is planned to be vacated as part of the planned park development. 2.1.2 Harrington Avenue NE Harrington Avenue NE is a north-south local access street.The existing drainage system within the project limits comprises curb and gutter,asphalt swale, catch basins, and storm drains.The topography slopes gently from north to south along the crowned existing roadway. Storm drains along Harrington Avenue NE were largely WBG103012044146SEA 1 DRFAFT PREDESIGN REPORT COPYRIGHT 2012 BY CH2M HILL ENGINEERS,INC..COMPANY CONFIDENTIAL SUNSET AREA LOW-IMPACT DEVELOPMENT RETROFIT IMPROVEMENTS installed incrementally as frontage improvements from developments, and they are sporadic along this corridor. The street stormwater runoff in Harrington Avenue north of NE 12th Street drains via a shallow storm drain along the west curbline or via surface flow along the east curbline to a storm drain trunk in NE 12th Street.The runoff from NE 12th Street to Sunset Boulevard (SR900) drains to storm drains that discharge to a storm drain trunk in Sunset Boulevard. Both storm drain trunks—NE 12th Street and Sunset Boulevard—combine at Edmonds Avenue NE.The street runoff along Harrington Avenue between Sunset Boulevard to NE 9th Street drains to the storm drain trunk in NE 9th. South of NE 9th Street the roadway drains to a storm drain trunk in NE 7th Street.These storm drains,from NE 9th Street and NE 7th Street, ultimately combine with the storm drains in Sunset Boulevard and discharge to Johns Creek. The project on Harrington Avenue NE can be subdivided into the following four segments: • North segment: NE 16th Street to NE 12th Street • Middle segment: NE 12th Street to NE 10th Street • South segment 1: Sunset Boulevard to NE 9th Street • South segment 2: NE 9th Street to NE 7th Street Each segment of the Harrington has unique character and constraints that were evaluated separately. 2.1.2.1 North Segment The north segment runs from NE 16th Street to NE 12th Street.The east side of the street is primary single-story, multifamily residential homes with an informal asphalt shoulder that functions as the sidewalk and periodic driveways. McKnight Middle School is located on the west side of the street with an existing 6-foot-wide sidewalk and existing street trees (approximately 10 years old). Off-site area from the east up to the Kirkland Avenue NE drains toward the project area.Additionally, King County Metro Route 105 travels on the west side (southbound) of the street. In general,the topography and character of this segment is more suitable for open, sloped bioretention facilities. 2.1.2.2 Middle Segment The middle segment runs from NE 12th Street to NE 10th Street.Single-and multifamily homes are located on both sides of the street. An apartment building is at the east side and south end of the segment.Two existing newer sidewalks were installed along the west and east sides immediately in front of the apartment. A storm drain system is installed outside the apartment on the east side of the street.This segment consists of more ' frequent and compact driveway locations and might be more suitable for a more compact(e.g. vertical side slopes) bioretention design that can fit within the existing space constraints and frontage improvements. Other emergent technology BMPs could be an alternative. 2.1.2.3 South Segments The south segment 1 starts south of Sunset Boulevard (SR900) and runs to NE 9th Street.This segment has commercial retails, restaurants, and apartment buildings on both sides of the street.There are existing sidewalks on both sides and southern portion of the street. An existing storm drain system is located on the east side in front of the apartment buildings. Due to the more commercial and mixed-use nature of this segment, it might be suitable for a more compact (e.g.vertical side slopes) bioretention design that can fit within the existing space constraints and frontage improvements. South segment 2 is the most southern segment, and it starts from NE 9th Street and runs to NE 7th Street. Highland Elementary school is located on the west side of the street.The school parking lot and playfield is 2 to 15 feet lower than the street. Single-family residential houses are located on the east side.An offsite area from the Kirkland Avenue drains toward the project area.An existing storm drain system is located outside the Highland Elementary School.Since the topography on the west side is lower than the street level, infiltration BMPs is not feasible. Open, sloped bioretention facilities is more suitable for this segment on the east side. WBG103012044146SEA 2 DRFAFT PREDESIGN REPORT COPYRIGHT 2012 BY CH2M HILL ENGINEERS,INC.•COMPANY CONFIDENTIAL SUNSET AREA LOW-IMPACT DEVELOPMENT RETROFIT IMPROVEMENTS 2.2 Site Infiltration Suitability The soil at the site is mapped as Arent, Alderwood material, (AmC), Ragner-Indianols association (RdC), and Urban (Ur).The Arent, Alderwood, and Ragner soil is classified as Hydrologic Group B soil, and Urban is classified as Hydrological Group C soil.The Ragner-Indianola association loamy,fine sand soil type is characterized as relatively permeable outwash soil with a moderate to high capability to transmit water. Arent and Alderwood material consists of moderately drained material from basal till.The material is classified with low to moderately low capability to transmit water.The Urban soil type is characterized as relatively impermeable glacial till overlain by weathered sand and gravel. Ten borings and two test pits were performed to determine the soil composition, and one selective grain size distribution and four field infiltration tests were performed in two of the borings and all of the test pit locations. The grain size distribution tests are performed in accordance with American Society for Testing and Materials (ASTM) Method D42Z Standard Test Method for Particle-Size Analysis of Soils (ASTM, 2007). The soil exploration founds loose to dense silty sand (SM), silty sand with gravel (SM), silt with sand (ML), and poorly graded sand (SP) near the surface for a depth of at least 10 feet along Harrington Avenue NE between NE 16th Street to NE 12th Street and south of Sunset Boulevard.This type of soil is feasible for infiltration. Glacially overconsolidated till was encountered at various depths underlying the silty sand and the silty sand with gravel soil at a depth between 1 and 7.5 feet between NE 12th Street and Sunset Boulevard.This type of soil is not feasible for infiltration. Groundwater was encountered in two borings at a depth of 15 to 20 feet.The more detail soil information can be found in the Sunset Stormwater Retrofit Low-Impact Development Project Geotechnical Date and Recommendations Report(CH2M HILL, 2012). 3. Design Criteria The City of Renton adopted the King County Surface Water Design Manual(King County, 2009)with City amendments (City of Renton, 2O1Ob)for the design, construction, and maintenance of stormwater management systems and facilities. Permanent stormwater features must meet the manual's design standards or be equivalent. John's Creek discharges to Lake Washington at Gene Coulon Park. Because of the proximity to Lake Washington, the stream's water elevation is controlled by the lake;therefore, it is considered to be a major receiving water body per the City of Renton's stormwater manual amendments.As a result,the redevelopment project within the John's Creek basin requires flow control mitigation to match peak flows under existing conditions for the 2-year, 10-year, and up to the 100-year storm events. The northern part of the project is located within the Aquifer Protection Area Zone2. City of Renton Municipal Code (RMC) 4-3-050, Critical Areas Regulations, addresses the requirement for development within or adjacent to the aquifer protection areas or any other critical area. Per the Sunset Area Surface Water Master Plan (City of Renton, 2011)the following target flow reductions were identified for the improvements included in this study: • Sunset Terrace Regional Stormwater Facility.This facility involves water quality treatment and flow control for 2.6 acres. For planning purposes,the current design is targeting an additional 0.3 acre as contingency. • Harrington Avenue Green Connections.The cumulative benefit of LID facilities along Harrington Avenue NE project was targeted to provide a flow reduction equivalent to a 0.60 reduction in effective impervious area. Ecology grant criteria targets the treatment of the existing impervious surface and PGIS: • Sunset Terrace Regional Stormwater Facility. Water quality treatment for 2.6 acres of impervious surface area. WBG103012044146SEA 3 DRFAFT PREDESIGN REPORT COPYRIGHT 2012 BY CH2M HILL ENGINEERS,INC.•COMPANY CONFIDENTIAL SUNSET AREA LOW-IMPACT DEVELOPMENT RETROFIT IMPROVEMENTS • Harrington Avenue Green Connections. Provide treatment to as much of the existing impervious surface area as feasible. 4. Proposed Drainage Improvements The preliminary design uses low-impact development (LID)techniques, such as bioretention swales, pervious concrete sidewalk, and emergent treatment technologies,to provide water quantity and quality control. 4.1 Best Management Practices 4.1.1 Bioretention Swale Bioretention swales are open swales with a wide bottom and are planted with native vegetation and grasses. An overflow structure will be installed to provide overflow when the water depth exceeds the 6-inch design ponding depth.The overflow water and water drains through the bioretention soil will be conveyed to a new or existing (if available) storm drain system. In extreme storm events or if the overflow structure becomes clogged, the water can overflow back to Harrington Avenue NE as a secondary overflow path.The bioretention swale overall width varies between 11.5 to 14 feet(from face of curb to front of sidewalk).The swale has a side slope of 3H:1V.The bottom width varies between 3.5 feet to 6.0 feet.The soils within the swale are replaced with 18-inch-thick bioretention soil,which has higher porosity, higher water retention, and increased permeability to enhance the available storage and infiltration occurring within the swale. The void ratio within the soil is modeled as 30 percent with a design infiltration rate of 4 to 6 inches per hour. Twenty (20)to thirty-six(36) inches of drain rock with 8-inch underdrains (6 inches from the bottom)will be installed at the bottom of bioretention swales.The underdrains are intended to protect the roadway pavement from the infiltrated stormwater runoff. End cap or orifice will be installed to control the release rate to the storm drain system and water infiltration volume into the native soil.The drain rocks and underdrain provides drainage to the Swale, and the ponded water should be drained within 24 hours after a storm event. 4.1.2 Pervious Concrete Sidewalk Pervious concrete sidewalk consists of an open-graded mix to allow an opening in the concrete structure so that _ water can percolate into a subsurface gravel layer and infiltrate into the underlying native soils. Pervious concrete sidewalk will be incorporated into the project where new sidewalks are proposed. 4.1.3 Emergent Treatment Technologies: Filterra® The Washington State Department of Ecology(Ecology) has a list of approved water quality treatment emergent treatment best management practices (BMPs). Filterra° is approved for enhanced and basic treatment with General Use Level Designation.This technology is a form of bioretention planter in a precast concrete box. The special mix of high hydraulic conductivity soil is placed in the facility with an underdrain underneath.The treated water is then discharged via the underdrain to a downstream catch basin.The planted tree in the facility provides biological uptake of the water and nutrients. Filterra° or other treatment technologies will be used where bioretention swales are not feasible due to site constraints and/or infiltration is not feasible. 4.2 Sunset Terrace Regional Stormwater Facility The regional stormwater facility is proposed to infiltrate 2.9 acres of impervious surface area. Most of the impervious area (approximately 2 acres)will be from Sunset Boulevard and NE 1Oth Street.Additional area from the shopping strip mall north of NE loth Street will make up to the remainder of the targeted 2.9 acres.A new conveyance system will be installed along NE 10th Street to convey water from the Sunset Boulevard storm drain system (north/west side)to the new facility. A flow splitter manhole will be installed to divert stormwater runoff from the strip mall to the facility. Flows exceeding the required flow to the regional facility to provide equivalent treatment and retention to 2.9 acres will be diverted back to the existing storm drain system in Harrington WBG103012044146SEA 4 DRFAFT PREDESIGN REPORT COPYRIGHT 2012 BY CH2M HILL ENGINEERS,INC.•COMPANY CONFIDENTIAL SUNSET AREA LOW-IMPACT DEVELOPMENT RETROFIT IMPROVEMENTS Avenue NE.A tributary area map is included in Appendix A,and the typical section of the facility is included in Appendix B. The facility is proposed for the northeast corner of the future park.The bioretention swale will be landscaped with water-tolerant plants, and the rest of the surface above the infiltration gallery will be graded and seeded so that it will be usable space for the park. Figure 1 shows the layout of the facilities. The bioretention swale is proposed at the north part of the facility,just behind the sidewalk to provide water quality treatment of the runoff.The swale will have a side slope of 3H:1V or flatter and a maximum of 6 inches ponding and 6 inches of freeboard prior to overland overflow.An overflow structure will be located within the swale to provide secondary outlet during large storm events. Per Ecology guidelines the design infiltration rate for bioretention is approved at 12 inches per hour;therefore, using a factor of safety of 2 an infiltration rate of 6 inches per hour was used.The infiltrated water and the overflow water will then drain to the underground infiltration gallery.The infiltration gallery consists of 36 inches thick of drain rocks with perforated pipes(6 inches minimum from the bottom of the drain rocks)for even water distribution. WBG103012044146SEA 5 DRFAFT PREDESIGN REPORT COPYRIGHT 2012 BY CH2M HILL ENGINEERS,INC.•COMPANY CONFIDENTIAL L "Z. % 1 0 ,0z Z, ' Z Ar rW w $ � s Connect to Existing d Storm Drain �r 0 � J % .,. 5 / Connect ' to Existing st Storm Drain b } SUNSET gL1/D=(SR=8001t', Connect to Existing 1 Storm Drain V LEGEND ® Rain Garden Infiltration Gallery —+--` Storm Drain FIGURE 1 Proposed Stormwater Sub-Regional Facility Ao 10o zoo soo SunsetArea LID Pre-Design North Approximate scale in feet October 2012 WBG101612144602.RSLIDD 01 SitePlan CH2MHILL.o _ SUNSET AREA LOW-IMPACT DEVELOPMENT RETROFIT IMPROVEMENTS 4.3 Harrington Avenue NE Bioretention swales are proposed to be installed along the Harrington Avenue NE for water quality treatment and some flow control. Based on the existing surface features,tributary areas, land uses, and storm drain systems,the bioretention swales were proposed at each segment.The layouts are shown on Figures 2 through 5B. The tributary area to the swales in each segment is included in Appendix A.Table 1 shows the tributary areas in the design, and Table 2 shows the size of the bioretention swales in each segment of the road. Typical cross- sections of the road are included in Appendix C. See Section 5, Design Analysis, below for more discussion for the results. TABLE 1 Tributary Areas to Bioretention Swales on Harrington Avenue NE Green Connections Pollutant- Generating Tributary Area Impervious Area Impervious Surface Pervious Surface Segment (acre) (acre) (acre) (acre) North:NE 16th Street to NE 12th Street 4.33 1.89 1.41 2.44 Middle:NE 12th Street to NE loth Street 3.45 1.85 1.30 1.60 South 1:Sunset Boulevard to NE 9th Street 1.16 1.16 1.16 0 South 2:NE 9th Street to NE 7th Street 2.63 1.78 0.99 0.85 Total 11.57 6.68 4.55 4.89 TABLE 2 Proposed Bioretention Swale Size Bioretention Swale Size(length x width) West Side of Street East Side of Street Sizing Factor' Segment (feet) (feet) (percent) North: NE 16th Street to NE 12th Street 150 x 5.5 440 x 3.5 2.9 Middle:NE 12th Street to NE loth Street 110 x 5 170x 5 1.7 South 1:Sunset Boulevard to NE 9th Street 120 x 5 80 x 5 2.0 South 2:NE 9th Street to NE 7th Street N/A 280 x 6 2.2 Total Length 380 970 2.2 Sizing factor is the bioretention swale bottom area divided by the tributary impervious area N/A not applicable WBG103012044146SEA 7 DRFAFT PREDESIGN REPORT COPYRIGHT 2012 BY CH2M HILL ENGINEERS,INC.•COMPANY CONFIDENTIAL 4 77 Legend Remove SW Structure �' s' `j11Z w , ,. Proposed Grate Cover V �a 5 ® Xw Proposed SW Structure - ---- Remove Pipe s t ,�" � Abandon Pipe17 -�- Proposed Drainage System 0 Existing SW Structure —10— Existing Drainage Sysem Ij Proposed Planter Area s /� Proposed Bioretention Swale r,-7 i e Proposed Sidewalk LRenton ParcelsGQ � w w : 1 25 50 100 Feet w., 4111 411 R apt:, -� Al tN - 6 IF•: t6 of � a l� j � � �� �': ���'. `K ,��+ ' la's •2�" Ra l" h ` "t m } m 101 -, 'A xX 4,• �., ks .a °t n S /) ddm .. . f 1 Harrington Avenue '$ . g i - a tt Green Connections W North Segment RY Figure 2 -A � � Harrin ton Avenue NE - Proposed BMPs g Sunset Area LID Pre-Design 10-23-2012 GH2MHILL Legend N 3 Remove SW Structure w t ® Proposed Grate Cover t ... 3 Proposed SW Structure ` >t ---- Remove Pipe54 Abandon Pipe , , ' Proposed Drainage System �, �� { ` •" Existing SW Structure 1 Existing Drainage Sysem Proposed Planter Area Proposed Bioretention Swale - Proposed Sidewalk 5 __ .•� �� rrir3...�++ 2rp .. :`fie"" � �'", Renton Parcels ', g 25 50 100 6 a c Feet (1 Ir h �"iT urn,1i� ,J.. r � �I�•S� I ��' � (?� >_ ZV k LU ° s r A 9 M �. ""Ai 441 J. ay 1 n` �:a � �¢ �� ✓ � �� � � ��� � „ems x, � a �,• I « 4 W, . ! .�,x -Y sdl% x t i `fir-, +, t 67W' � `' 4 nQ � _ � . ® t, E 13th St 4dP- Harrin ° ton Avenue Green Connections 71 ► ►�" a North Segment ` € 1 Figure 2 - B Harrington Avenue NE - Proposed BMPs N Sunset Area LID Pre-Design 10-23-2012 '• Legend — -- - --� Proposed Grate Cover ® Proposed SW Structure w �` —®— Proposed Drainage System s A Remove SW Structure ---- Remove Pipe ^4 e t —f— Abandon Pipe- z a 0 Existing SW Structure � R —►— Existing Drainage Sysem Proposed Planter Area Proposed Bioretention Swale s1 Proposed Sidewalk . �' "' g•_�a `^ M -. 1 Renton Parcels r -ava _..-25 50 100Iff f" �� < Feet � ;; � r g od Ave !'rivat Rd F y 41. ,5 ' t , e { _ - - 5 ^}ftz 1 A14 14. Lij (7 - a u Y 4 'it R � @ T ' ',r �m }•, p4 a as h a; C w; 8 Tie. yea 4 �j WF f \ Harrington AvenueA ill r . Green Connections g, � o Figure 3 Harrington Avenue NE - Proposed BMPs North Segment Sunset Area LID Pre-Design 10-24-2012 C!^#2MHILL Legend 'A' Proposed Grate Cover wti} + Oj w �,, Proposed SW Structure *`; t° GJ t ' � Proposed Drainage System p g y Remove SW Structure --- Remove Pipe » m� � t.i9 �—Abandon Pipe , s z - Existing SW Structure Ai 10 — Existing Drainage Sysem 4 1 d Proposed Planter Area +' '0 � Proposed Bioretention Swale + A ° 1P y/ a Proposed Sidewalk Renton Parcels fi 25 50 100 ,s 4•z ; l Feet I t tw ; 00011 A r ' 2 .•.,r» _ —_._ __.., � �w�..M q yam[ y¢r\ c» r �F S OM W IL 4 � 6_ F £` i 0 ,E e fi ' Aft .A �,�/• t q t » "A 7 44, _, 000 "lef Y 4 ...N� .w 'w7 ., k W r Harrington Avenue Green Connections '° -. Figure t, Harrington Avenue NE - Proposed BMPs South Segment 1 { Sunset Area LID Pre-Design n 10-23-2012 H2MFULL Legendth_ l a ' Proposed Grate Cover w�(�y RF F M Q Proposed SW Structure ra � 8 S Proposed Drainage System .+w...F1'ux.�'.TR. '�. 'Y 5 T 3• S Remove SW Structure t�• t --- Remove Pipe —� Abandon Pipe �,: •� ,�� �� %. Existing SW Structure 7r � a —� Existing Drainage Sysem Proposed Planter AreaafY�axr E *fir Proposed Bioretention Swale Proposed Sidewalk . � f ff_ r W t.. __.. Renton Parcels 25 50 100 13 p Feet 41 LU F I ; o •, NE 8th P1 CID AJ M1 CU e � 10 INS - �. +{tom �"�H � ..t £ � F (� �� ♦ � .°1& ... f+i'^1 �'iYrr'•IR:.4...r!+eWta.,'S+F �.� � .z f �s kit.A: ,,.` � .� x S 9 Ili s.,_a• ce ♦ •ic •, i 3 � 4 1 v E NE 8th St w , .� ,et", I'�•- � it q. y. �'�'s .t d,';" � �v. r Harrington Avenue # Green Connections South Se nt 2 me g ' I l AN a x Figure 5-A ��� Harrington Avenue NE - Proposed BMPs VL Sunset Area LID Pre-Design 10-23-2012 �q I Legend ® Proposed Grate Cover Proposed SW Structure , �— Proposed Drainage System Remove SW Structure b� ' W --- Remove Pipe —�Abandon Pipe I Existing SW Structure —� Existing Drainage Sysem .� w Proposed Planter Area tt C Proposed Bioretention Swale m Proposed Sidewalk - l g Renton Parcels 25 50 100 / w NE 8th PI Feet C ter. > OW. y '� } C R t�Cr` ON 1 i �� 0 tA wmg VWr-4 7 t , e NE 8th St t h� 14 ? d 7r t Mm aew+M _ 44 AA e, x �rh3 r , N f.. � :i t 7th St 2 fit, IS = ' Harrington Avenue - Green Connections South Segment 2 _, rt Figure 5-13 Harrington Avenue NE - Proposed BMPs Sunset Area LID Pre-Design �;•,.,_ 10-23-2012 H2MHILL SUNSET AREA LOW-IMPACT DEVELOPMENT RETROFIT IMPROVEMENTS 5. Design Analysis The bioretention swale locations were determined based on existing site conditions including the topography, driveway access,features and impacts at the adjacent property, and existing storm drains locations. Geographic information system (GIS) data and aerial photographs from the City of Renton were used to delineate the tributary area and calculate the land covers. Ecology's Western Washington Hydrological Model V3 (WWHM; Ecology, 2012)was used to model the hydrology of the project area and the proposed LID facilities.This model simulates a 50-year rainfall record based on the Seattle-Tacoma International Airport rain gauge with a scale factor of 1. 5.1 Sunset Terrace Regional Stormwater Facility Stormwater runoff from smaller storm events will be infiltrated while the runoff from larger storm events will be released slowly through an elevated orifice(s) in the flow control manhole to the storm drain system. Code for this area of the City is to match runoff from existing conditions. Therefore, the target peak flow rate for design of the regional facility is to match the peak stormwater runoff from the existing non-impervious condition, assumed to be grass/lawn, where new impervious would be added.The area the regional facility could serve is approximately 53 percent outwash and 47 percent till soil according to the City of Renton GIS information (1.54 acres of outwash grass and 1.36 acres of till grass). A flow splitter is proposed at the north side of NE10th Street to collect runoff from the strip mall and divert runoff from an equivalent needed area to the facility.The rest of the runoff will be divert back to the existing storm drain west of the facility. The proposed subregional facilities were sized to provide a swale bottom surface area of 1,200 square feet(150 feet x 8 feet), resulting in an area ratio of approximately 1 percent to the runoff contributing area.The underground infiltration gallery was sized to provide an area of 10,500 square feet.An elevated orifice is proposed to control the release of the stormwater runoff in excess of the infiltration capacity of the native soils. Table 3 shows the reduction in peak flow rate. In general,the peak flow rate was reduced for 2-year to 100-year storm events.The release rate meets or exceeds the peak flow control standard requirements. More than 92 percent of the runoff volume will drains thru the bioretention soil for treatment and more than 99 percent of runoff volume will be infiltrated into the native ground. Less than 1 percent of the runoff volume will be discharge to the storm drains at Sunset Boulevard.The reduction in runoff peak flow rate and runoff volume will improve the water quality and quantities at John's Creek, and Lake Washington.The WWHM model input and output is included in Appendix D.The released water will discharge to a new storm drain combining with the existing storm drains from the Harrington Avenue NE. TABLE 3 Peak Flow Rate of the Targeted and Proposed Conditions for the Sunset Terrace Regional Stormwater Facility Targeted Mitigated Storm Event (ft3/s) (ft3/s) 2-year 0.073 0.064 5-year 0.124 0.123 10-year 0.167 0.162 2S-year 0.231 0.207 SO-year 0.288 0.236 100-year 0.353 0.262 Note:Peak flow rates are based on WWHM(Ecology,2012)output using hourly time-steps. ft3/s cubic feet per second The facility will be further refined in coordination and collaboration with the RHA and City of Renton Community Services for the location, layout,grading, and landscaping features. WBG103012044146SEA 20 DRFAFT PREDESIGN REPORT COPYRIGHT 2012 BY CH2M HILL ENGINEERS,INC.•COMPANY CONFIDENTIAL SUNSET AREA LOW-IMPACT DEVELOPMENT RETROFIT IMPROVEMENTS - 5.2 Harrington Avenue NE Seven WWHM models were performed to evaluate the treatment volume and flow reduction: • East and west side of Harrington Avenue NE between NE 16th Street to NE 12th Street • East and west side of Harrington Avenue NE between NE 12th Street to NE 10th Street • East and west side of Harrington Avenue between Sunset boulevard to NE 9th Street • East side only for the segment between NE 9th Street to NE7th Street. For each model, a tributary area is routed to a single Swale representing the total length of the swale within that project segment.The length of the swale and the size of the orifice were adjusted to maximize peak flow rate reduction and infiltrate a minimum of 91 percent of the runoff through the bioretention soil.Adding the underdrain with orifice control results in a slight increase the release rate of runoff during the smaller storms but maintains available storage to provide peak-flow reduction for the larger storm events.This conceptual design maximizes the available space for bioretention swales and,therefore, exceeds the current targets. Future design refinements will likely reduce the extent of bioretention swales as additional site constraints are evaluated (e.g. utilities). According to the geotechnical exploration,the design infiltration rate for the project is 1.2 inches per hour, except the segment of Harrington Avenue NE between NE 12th to NE 10th Streets where infiltration is not considered feasible. According to the model results,the peak flow rates reduction are approximately from 26 to 63 percent.The flow reduction reported is equal to the lowest reduction from the 2-year to the 100-year recurrence interval storm events as reported by WWHM (Ecology, 2012).All of the tributary areas are treated to the water quality standard of infiltrating 91 percent of the runoff volume through the bioretention soil.Table 4 shows the flow reduction percentage and treated volume percentage.The WWHM model input and output can be found in Appendix D. TABLE 4 Treatment Volume and Flow Reduction Percentage from BMPs Equivalent Flow Removal of Flow Treated Reduced Impervious Corresponding Appendix D Area Tables Harrington Avenue NE Segments (percent) (percent) Area(acres) and WWHM Model Outputs North:NE 16th Street to NE 12th Street 96% 63% 1.2 Area Table 2A and 2B and WWHM Model Outputs[NH-E-1011]and[NH-W-1011] , Middle:NE 12th Street to NE loth Street 93% 26% 0.5 Area Table 3A and 3B and WWHM Model Outputs[MH-E-1011]and[MH-W-1011] South 1:Sunset Boulevard to NE 9th Street 95% 30% 0.3 Area Table 4 and WWHM Model Output [[SH-N-1014] South 2:NE 9th Street to NE 7th Street 93% 44% 0.8 Area Table 5 and WWHM Model Output [SouthHS_E_vl] Total 2.8 WWHM Western Washington Hydrology Model(Ecology,2012) The bioretention swale dimensions and size and elevation of the orifice will be further refined in future design phases based on the actual site conditions and public input.Also, other BMPs, such as pervious concrete sidewalk or other emergent treatment technology can be included to compensate for lost available bioretention Swale area due to site constraints. WBG103012044146SEA 21 DRFAFT PREDESIGN REPORT COPYRIGHT 2012 BY CH2M HILL ENGINEERS,INC.•COMPANY CONFIDENTIAL - SUNSET AREA LOW-IMPACT DEVELOPMENT RETROFIT IMPROVEMENTS - 5.3 Issues for Further Consideration This predesign report was prepared to further the conceptual analysis, refine the evaluation and goals of the project and identify issues to be addressed in the design phase of the project. Key challenges and issues that are to be addressed in the next phase of the project are summarized below and in the attached review comments of the draft Pre-Design Report: • Preservation of existing trees where feasible is consistent with the LID approach and will be a continued goal on the project. A preliminary arborist study was conducted along the Harrington Avenue NE corridor and will continue to be consulted during the design phase. • The proposed bioretention facilities (or rain gardens)will be designed to fit the context of the streetscape and/or park. Design will be closely coordinated with landscape architects, City of Renton Transportation and Parks departments and the public to achieve this goal. • On-going operations and maintenance responsibilities need to be defined during the design stage. • The design of curb extensions along Harrington is likely to affect on-street parking. The design phase will coordinate and minimize impacts to parking to the extent feasible as well as define signage requirements. • The proposed layout and improvements will be refined to preserve as much of the existing storm drainage system as possible. • Tributary flow to the Sunset Terrace Regional Stormwater Facility is currently planned to come from SR 900 and a portion of the neighboring commercial development at the NW corner of SR 900 and NE 10th Street. Inflow from the commercial development may need to be plumbed through a flow splitter facility. • Existing utilities will be located and potholed where necessary to avoid conflicts. Some revisions to the design, particularly due to an existing waterline along the east curbline of Harrington, may be necessary. • Pervious concrete sidewalk section, i.e.the reservoir course,will be sized to infiltrate 100 percent of the rainfall. • There is an opportunity to coordinate with other infrastructure improvements in the area, reducing costs and construction disruptions to the neighborhood. In particular, a new water main may be provided along Harrington Avenue NE between NE 10th Street and NE 121h Street. WBG103012044146SEA 22 DRFAFT PREDESIGN REPORT COPYRIGHT 2012 BY CH2M HILL ENGINEERS,INC.•COMPANY CONFIDENTIAL SUNSET AREA LOW-IMPACT DEVELOPMENT RETROFIT IMPROVEMENTS 6. Cost Opinion A cost opinion was developed based on the conceptual design layout(Figure 1 to Figure 5).Table 5 below lists the project total construction cost.The breakdown of the construction cost is included in Appendix E. TABLE 5 Cost Opinion Project Construction Cost Sunset Terrace Regional Stormwater Facility $600,000 Harrington Avenue NE North Segment:NE16th Street to NE12th Street $810,300 Harrington Avenue NE Middle Segment NE12th Street to NE10th Street $427,100 Harrington Avenue NE South Segment 1:Sunset Boulevard to NE9th Street $219,000 Harrington Avenue NE South Segment 2:NE 9th Street to NE 7th Street $514,700 Total $2,571,100 The construction costs include the installation of the new bioretention swales, new pervious concrete sidewalk, new storm drains, and pavement restorations. Allowances were added for miscellaneous detail allowance (10 percent), traffic control, mobilization (10 percent), contingency(30 percent), and state sales tax(9.5 percent).The cost represents the construction cost in October 2012. No right-of-way acquisition was anticipated, and all of the stormwater facilities and conveyance systems will be constructed within the City's right-of-way. The City is in the process obtaining Ecology grants for the project's design and construction cost.The City is anticipated to receive$982,000 for the Sunset Terrace Regional Stormwater Facility and $913,000 for the Harrington Avenue NE.The project will be design and constructed using the combination of Ecology grants and City funds. In the next phase of design for Harrington Avenue NE,the project will focus on the segments north of NE10th Street. Further design refinements will be made to reduce construction cost, such as reducing conveyance and restoration cost and reducing the length of bioretention swales while meeting the design targets and criteria, and matching the available fund. - WBG103012044146SEA 23 DRFAFT PREDESIGN REPORT COPYRIGHT 2012 BY CH2M HILL ENGINEERS,INC.•COMPANY CONFIDENTIAL SUNSET AREA LOW-IMPACT DEVELOPMENT RETROFIT IMPROVEMENTS 7. Reference ASTM. 2007. Method D422, Standard Test Method for Particle-Size Analysis of Soils. American Society for Testing and Material, West Conshohocken, Pennsylvania. CH2M HILL. 2012.Sunset Stormwater Retrofit Low-Impact Development Project Geotechnical Data and Recommendations Report. Prepared for the City of Renton,Washington.August. City of Renton. 2010a. Draft Sunset Area Community Planned Action NEPA/SEPA Environmental Impact Statement. Prepared for City of Renton and Renton Housing Authority.Available at: http://rentonwa.gov/uploadedFiles/Business/CED/planning/2010/Volt SunsetArea-PA DraftEIS.pdf. City of Renton Community and Economic Development, Renton, Washington. December. City of Renton. 2010b.Amendments to King County Surface Water Design Manual.Available at: http://rentonwa.gov/uploaded Files/Government/PW/UTILITIES/Surface Water/City%20Amendments%2 Oto%20the%20King%20County%20Surface%20Water%20Design%20Manual.pdf. City of Renton, Public Works Department, Surface Water Utility, City of Renton,Washington. February. City of Renton. 2011.SunsetArea Surface Water Master Plan. City of Renton, Community and Economic Development Department and Public Works-Surface Water Utility Department, Renton,Washington. April. Ecology. 2005.Stormwater Management Manual for Western Washington. Available at: http://www.ecy.wa.gov/programs/wq/stormwater/manual.htmi. Washington Department of Ecology, Olympia, Washington. April. Ecology. 2012. Western Washington Hydrology Model. Version 3.0. http://www.ecy.wa.gov/programs/wq/stormwater/wwhmtraining/wwhm/wwhm v3/index.html. Washington Department of Ecology, Olympia, Washington. King County. 2009. King County, Washington, Surface Water Design Manual. Available at: http://Vour.kingcounty.gov/dnrp/library/water-and-land/stormwater/surface-water-design- manual/SWDM-2009.pdf. King County Department of Natural Resources and Parks, Seattle,Washington. January 9. Rusciano, G. M., & Obropta, C. C. (January 01, 2007). Bioretention Column Study:Fecal Coliform and Total Suspended Solids Reductions. Transactions of the Asabe, 50,4, 1261-1269. WBG103012044146SEA 24 DRFAFT PREDESIGN REPORT COPYRIGHT 2012 BY CH2M HILL ENGINEERS,INC.•COMPANY CONFIDENTIAL Appendix A Tributary Area Maps Legend ti '� , � ':.•s A �y� : �}�A� w !"'A [mot LID Drainage Basins Tributary Roads - y y 'A2` d v - A6—, Tributary Roofs -" 4. a , Contours Renton Parcels i r 0 75 150 300 FPP1Voi --�_..-..... �+ � t ti it " ask /���• �� _0 N tY i c W 04 Olt �Y s JA 1 z genet �� �`�` `• ; ' a t ! / a d { = .w E _ - •�� i 1< � + �1`°'�;tFfi it .� t! �-, ,;_ � �a�ra �'� EVE12thSfi .�- ^F.1 , 1 ,� •i ,�,� ;p, y� L(L .,rir'Al1 ♦.# . Y.• F �� >ie I�� t�S. �-'"'r+•-= E ! y ��i Y� `� � �� {r�� �'�f'�', R" !� e t' ;[ a �� ,i F �.r� 1� ���1`�S �Arl sk iv, Y4 l ` ,rc r�.' �*•~ F k Rix '4�� ,y.x�^ t Jr`\.v v'-. 1 .♦ }fib. x�.q•-4 a'p T , lYo� 1 �° � � ., _ 1^ :, 'ter. Mh.-. �F• �„ �� cc IV $ ������ _ ,► �- ✓ ���•. u'.? Ste" psi 1 C� d ,M ZZ11 y� 2 / �♦• •6 �Y e 4 v,JAL Je ��. -Q' f ► ' � jYw 4f�# ��/p J, in _ Y ! y 57 f e • v H R 3 •,. 'a s -' ` ' 1:11 _.'� a a - •-A y� t 1 O w �.' s 392 co �tk l .y 1 �yy . d +k }� S fillt '"' ti C 1 qt y a Aft r 9 M d Sunset Terrace Figure A-1 M Sub-Regional Stormwater Facility Drainage Tributary Area ¢ Regional SW Facility - Sunset Area LID Pre-Design 012 u� NF C*42 : HILL d r • 8p Legend ; LID Drainage Basins — Tributary Roads r "'MIN t Tributary Driveways r � a *al Tributary Roofs Contours A Renton Parcels 0 25 50 100 Feet y, �• t1 `. a ,. ° 7 �� — S AAi 6 ik 1180 rt 4* 0 'All " 6 77 AL v<1 \ a'�p • may;1 �` w W 'L ^ n ^ ' ` �RYPw�d A y� _ r w CO Or VIL /"'. .: i Rj �.'"ICY"''. `•, - . 1.,�.,. I @.. 1 .,..a 1 N rti�, .F'� 4`� x � - �.'- � �"t• & s�� � � 0 �rf0s 1�-� 1M�Ai'1--...W,.uir I"� � s�" ��a�,G` ' d 2 t,, t" Wbswk §. A left R M\ :,,moms ^ �KA , A Al Ra aft 40 •.T1' xa �e b � �� � ,.� ��s �� �� •.I.i. i,,;s�taglrr.:m wa,s+�",\.�11� � _..^ �a L&�..� _'��� _ Wk 35 � �� -� '• �' _ I G i �'�� ,�a� � � �� .,�� fir,+T 0 � w 'v 24— Harrington Avenue AJI Green Connections s North Segment ` Figure A-2 Drainage Tributary AreaHarrin ton Avenue NE Sunset Area LID Pre-Design trl � 10-26-2012 CH21VIIHILL Legend wy n ®LID Drainage Basins ��// �•.� -, _ � `� ' S — Tributary Roads Tributary Driveways t 354 Tributary Roofs — Contoursy '` Renton Parcels 0 25 50 100 t� Feet � ,�. � it-__ _..,�.�", � �,� ��•` a �. t a -a 7. KL'�'!E'°"``rr.1G:3C"+emu +c." d t C:" r ' b.. js"6J�s C`�'� r+F«`d F ,�.^ °" 'w� FF a..-� •s,�K:.aw,yaw. ad,.,y „� - AOW l " Wr " '" %'n" P O f Y°$ ski s •r E7 /J s 1 T�' ♦ P `�e Egg �r o k not . %�,i�i ♦ ((� 3f 1NO a �.f t ' 1 ko • " .w....wTSrt`s# ,A .. ''+„, It #1 348 f k w I iarrington Avenue Af� * �� Green Connections N. �.,r r'/ k " 1 ��. �,.�., �A . Middle Segment P tw r Figure A-3 Harrington Avenue NE - Drainage Tributary Area - NE ?Oth Sunset Area LID Pre-Design t S 10-26-2012 CH2MHILL Legend w+r LID Drainage Basins 4 � ,, 4 ' Tributary Roads '� Tributary Driveways Tributary Roofs i � ^ a ^� � ,\ s OKI I Contours Renton Parcels 0 25 so 100 41 JAI, All 44 w ,• r 4o- Li ? * .�. �"�¢. �, �� � � � a•` � mix 'a Wit i to C y `�Srr E Q 3 ab «� { M CD 3 k * r_ � . �� ... Y�► .A .....M - "k r. pp ter`" ` Harrington Avenue ' 4 ; g Green Connections South Segment 1 " w key e >�J 40. 9t Figure A-4 Harrington Avenue NE - Drainage Tributary Area ,g t Sunset Area LID Pr D e- esign 10-26-2012 1CM-IMHILL Legend g w NE 9th St � LID Drainage Basins ' _ i = g �:, rl:x. �9 •�.� � .. Tributary Roads Mohr' r; >, ;r 4 _ w. 4 IV Tributary Driveways , Tributary Roofs �V f M 1, k 4 — Contours ;.'�• 1 Renton Parcelsa 0 25 so ioo ..Feet _ % 4 /` M ✓ x '�} Wt t� Mrs 'IR CP xbLU Ali 14, OD 4. IL 1 1l jja 318 W X .{I c I' E 8th PI` '° m. .fix a". ►......�.... ar.. fir- .b. r '�� ', � r � � � :"t A .,+��� i 'XAi a ILE � �« � � � ; • Atli ��u f max; -� 1%h , AL Jki .� '. NE 8th St r ' w.� G''/ 'rat i , ., t CD Ot ,. � i � �`.�,� ass`.»>: ' .�..� _�, ,� t:� � ✓. �> � 7�':y � ► m i. + };., •' \ i , i$ . ;+ s � �••,f a '' i -'� \I tC ', '�3 ^mot i§e o i t Harrington Avenue Green Connections i South Se ment 2 t Figure A-5 e AWN Harrington Avenue NE - Drainage Tributary Area Sunset Area LID Pre-Design m� t � 10-26-2012 2 HIL CH2M HILL TRANSMITTAI PROJECT NAME: City of Renton Sunset Terrace Regional Stormwater Facility Project To: City of Renton PUD 1055 S. Grady Way, 511 Floor Renton, WA 98057 From: Raymond Chung, PE 1100 112'h Avenue NE, Suite 500 Bellevue, WA 98004 Attn: Hebe C. Bernardo July 8, 2014 Re: Sunset Terrace Regional Stormwater Facility We Are Sending You: X Attached Under separate cover via Shop Drawings Documents Tracings Prints Specifications Catalogs Copy of letter Other: Quantity Description 1 copy Contract No. CAG-13-021,Addendum No. 1, Sunset Terrace Regional Stormwater Facility, Executed 3 copies Summary Technical Memorandum,July 1,2014 3 copies Engineer's Estimate, Schedule A—Storm Drain and Facility Improvements 3 copies City of Renton Community Low Impact Development Retrofit Project Sunset Terrace Regional Stormwater Facility—2014(30%Submittal—Not for Construction) If material received is not as listed, please notify us at once Remarks: Copy To: File 4 i TECHNICAL MEMORANDUM GH2MHILLa Summary PREPARED FOR: Hebe Bernado/City of Renton COPY TO: Dustin Atchison P.E./CH2M HILL PREPARED BY: Chung, Raymond, P.E./CH2M HILL DATE: July 1, 2014 PROJECT NUMBER: 469392 This memorandum summarizes the design concept of the Sunset Terrace Regional Stormwater Facility. Project Setting The Sunset Terrace Regional Stormwater Facility is proposed to be located in the Sunset Terrace neighborhood, bordered by Harrington Ave NE, NE 10th Street and Sunset Lane.The site generally slopes gently from northeast to the southwest.The stormwater water facility will consists of two (2) connected bioretention cells and an underground infiltration gallery beneath the cells. The tributary area to the facility is public right of way on Sunset Boulevard (SR900), NE 10th Street, and also private property on the Greater Highland Shopping Center.The stormwater runoff from Sunset Boulevard and NE 10th Street will be conveyed directly to the facility, while the runoff from the Greater Highland Shopping Center will flow through a flow splitter redirecting approximately 0.97acres of the 5.4 acre site to the regional facility. TABLE 1 Regional Stormwater Facility Tributary Areas Location Impervious Area(acres) Sunset Boulevard 1.79 NE loth Street 0.14 Greater Highland Shopping Center 0.97 Total 2.90 Facility Configuration The bioretention cells'total bottom area is approximately 1500 square feet with 3H:1V side slopes.The bioretention cells consists of a mulch layer and 18 inch layer of bioretention soil. Approximately 10%of the total bioretention cell area will be used for pre-settling, and located in cell 1.The two cells will treatment runoff by filtering it through the bioretention soil and vegetation. The top of the cells is at elevation 340 feet; the bottom of cell 1 (840 square feet) is at elevation 336.50 feet; cell 2 (700 square feet) is at elevation 336.33 feet. An 18-inch diameter pipe will connect the two cells to allow their depths to equalize.The treated flow will enter the 150 feet by 70 feet underground infiltration gallery located beneath them. REGIONAFACILITYTM_30%_V2/[INSERT DOCUMENT LOCATOR] COPYRIGHT[INSERT DATE SET BY SYSTEM]BY[CH2M HILL ENTITY].COMPANY CONFIDENTIAL The infiltration gallery consists of a 36-inch thick layer of drain rock(type 26 mineral aggregate per City of Seattle specs). Five 12-inch diameter slotted underdrain pipes at 15 foot spacing within a level aggregate layer(approx. bottom elevation 331.83) should encourage uniform infiltration throughout the gallery. Manholes on one end of each underdrain and a cleanout is on its other end will facilitate the maintenance of the system. Within cell 2,flows exceeding the water quality flow (6 inches of ponding) will overflow into an overflow catch basin (elevation 337.0 feet and directly into the infiltration gallery. With the selected design (long term) infiltration rate of 1.2 inches/hour, approximately 99.9%of the historical runoff volume entering the facility is predicted to infiltrate into the native soil. The maintenance manholes on the east end of the underdrain are connected by 18-inch storm drain to form a manifold.The downstream manhole in the manifold is a 60-inch diameter flow control structure with a riser pipe.The top of the riser(overflow elevation) is set at the top of the drain rock layer such that the runoff will infiltrate to the native soil, and flows exceeding it's total storage will overflow to the downstream storm drain. A secondary overflow structure within cell 1 with rim elevation 337.25 feet will also provide conveyance during extremely large storm events or when the overflow structure or the flow control system is clogged. The outlet of the stormwater facility will be installed along the existing Sunset Lane then connect to an existing 12-inch storm drain system in Harrington Avenue NE that is 200 feet downstream of the facility. 2 REGIONAFACILITYTM_3O%_V2/[INSERT DOCUMENT LOCATOR] COPYRIGHT[INSERT DATE SET BY SYSTEM]BY[CH2M HILL ENTITY]•COMPANY CONFIDENTIAL TECHNICAL MEMORANDUM CH2MHIL.Le Summary PREPARED FOR: Hebe Bernado/City of Renton COPY TO: Dustin Atchison P.E./CH2M HILL PREPARED BY: Chung, Raymond, P.E./CH2M HILL DATE: July 1, 2014 PROJECT NUMBER: 469392 This memorandum summarizes the design concept of the Sunset Terrace Regional Stormwater Facility. Project Setting The Sunset Terrace Regional Stormwater Facility is proposed to be located in the Sunset Terrace neighborhood, bordered by Harrington Ave NE, NE 101h Street and Sunset Lane.The site generally slopes gently from northeast to the southwest. The stormwater water facility will consists of two (2)connected bioretention cells and an underground infiltration gallery beneath the cells. The tributary area to the facility is public right of way on Sunset Boulevard (SR900), NE 10th Street, and also private property on the Greater Highland Shopping Center.The stormwater runoff from Sunset Boulevard and NE 10th Street will be conveyed directly to the facility, while the runoff from the Greater Highland Shopping Center will flow through a flow splitter redirecting approximately 0.97acres of the 5.4 acre site to the regional facility. TABLE 1 Regional Stormwater Facility Tributary Areas Location Impervious Area(acres) Sunset Boulevard 1.79 NE 10th Street 0.14 Greater Highland Shopping Center 0.97 Total 2.90 Facility Configuration The bioretention cells'total bottom area is approximately 1500 square feet with 3H:1V side slopes.The bioretention cells consists of a mulch layer and 18 inch layer of bioretention soil.Approximately 10%of the total bioretention cell area will be used for pre-settling, and located in cell 1. The two cells will treatment runoff by filtering it through the bioretention soil and vegetation.The top of the cells is at elevation 340 feet; the bottom of cell 1 (840 square feet) is at elevation 336.50 feet; cell 2 (700 square feet) is at elevation 336.33 feet. An 18-inch diameter pipe will connect the two cells to allow their depths to equalize.The treated flow will enter the 150 feet by 70 feet underground infiltration gallery located beneath them. REGIONAFACILITYTM_30%_V2/[INSERT DOCUMENT LOCATOR] COPYRIGHT[INSERT DATE SET BY SYSTEM]BY[CH2M HILL ENTITY]•COMPANY CONFIDENTIAL The infiltration gallery consists of a 36-inch thick layer of drain rock(type 26 mineral aggregate per City of Seattle specs). Five 12-inch diameter slotted underdrain pipes at 15 foot spacing within a level aggregate layer(approx. bottom elevation 331.83) should encourage uniform infiltration throughout the gallery. Manholes on one end of each underdrain and a cleanout is on its other end will facilitate the maintenance of the system. Within cell 2, flows exceeding the water quality flow(6 inches of ponding) will overflow into an overflow catch basin (elevation 337.0 feet and directly into the infiltration gallery.With the selected design (long term) infiltration rate of 1.2 inches/hour,approximately 99.9%of the historical runoff volume entering the facility is predicted to infiltrate into the native soil. The maintenance manholes on the east end of the underdrain are connected by 18-inch storm drain to form a manifold.The downstream manhole in the manifold is a 60-inch diameter flow control structure with a riser pipe.The top of the riser(overflow elevation) is set at the top of the drain rock layer such that the runoff will infiltrate to the native soil, and flows exceeding it's total storage will overflow to the downstream storm drain. A secondary overflow structure within cell 1 with rim elevation 337.25 feet will also provide conveyance during extremely large storm events or when the overflow structure or the flow control system is clogged. The outlet of the stormwater facility will be installed along the existing Sunset Lane then connect to an existing 12-inch storm drain system in Harrington Avenue NE that is 200 feet downstream of the facility. 2 REGIONAFACILITYTM_30% V2/[INSERT DOCUMENT LOCATOR] COPYRIGHT[INSERT DATE SET BY SYSTEM]BY[CH2M HILL ENTITY]•COMPANY CONFIDENTIAL TECHNICAL MEMORANDUM CM2MHILLe Summary PREPARED FOR: Hebe Bernado/City of Renton COPY TO: Dustin Atchison P.E./CH2M HILL PREPARED BY: Chung, Raymond, P.E./CH21VI HILL DATE: July 1, 2014 PROJECT NUMBER: 469392 This memorandum summarizes the design concept of the Sunset Terrace Regional Stormwater Facility. Project Setting The Sunset Terrace Regional Stormwater Facility is proposed to be located in the Sunset Terrace neighborhood, bordered by Harrington Ave NE, NE 10th Street and Sunset Lane.The site generally slopes gently from northeast to the southwest.The stormwater water facility will consists of two (2) connected bioretention cells and an underground infiltration gallery beneath the cells. The tributary area to the facility is public right of way on Sunset Boulevard (SR900), NE 10th Street, and also private property on the Greater Highland Shopping Center.The stormwater runoff from Sunset Boulevard and NE 10th Street will be conveyed directly to the facility, while the runoff from the Greater Highland Shopping Center will flow through a flow splitter redirecting approximately 0.97acres of the 5.4 acre site to the regional facility. TABLE 1 Regional Stormwater Facility Tributary Areas Location Impervious Area(acres) Sunset Boulevard 1.79 NE loth Street 0.14 Greater Highland Shopping Center 0.97 Tota 1 2.90 Facility Configuration The bioretention cells'total bottom area is approximately 1500 square feet with 3HAV side slopes.The bioretention cells consists of a mulch layer and 18 inch layer of bioretention soil.Approximately 10%of the total bioretention cell area will be used for pre-settling, and located in cell 1.The two cells will treatment runoff by filtering it through the bioretention soil and vegetation.The top of the cells is at elevation 340 feet; the bottom of cell 1 (840 square feet) is at elevation 336.50 feet; cell 2 (700 square feet) is at elevation 336.33 feet. An 18-inch diameter pipe will connect the two cells to allow their depths to equalize.The treated flow will enter the 150 feet by 70 feet underground infiltration gallery located beneath them. REG IONAFACIL ITYTM_30%-V2/[INSERT DOCUMENT LOCATOR] 1 COPYRIGHT[INSERT DATE SET BY SYSTEM]BY[CH2M HILL ENTITY]•COMPANY CONFIDENTIAL The infiltration gallery consists of a 36-inch thick layer of drain rock(type 26 mineral aggregate per City of Seattle specs). Five 12-inch diameter slotted underdrain pipes at 15 foot spacing within a level aggregate layer(approx. bottom elevation 331.83) should encourage uniform infiltration throughout the gallery. Manholes on one end of each underdrain and a cleanout is on its other end will facilitate the maintenance of the system. Within cell 2, flows exceeding the water quality flow (6 inches of ponding) will overflow into an overflow catch basin (elevation 337.0 feet and directly into the infiltration gallery. With the selected design (long term) infiltration rate of 1.2 inches/hour, approximately 99.9%of the historical runoff volume entering the facility is predicted to infiltrate into the native soil. The maintenance manholes on the east end of the underdrain are connected by 18-inch storm drain to form a manifold.The downstream manhole in the manifold is a 60-inch diameter flow control structure with a riser pipe.The top of the riser(overflow elevation) is set at the top of the drain rock layer such that the runoff will infiltrate to the native soil, and flows exceeding it's total storage will overflow to the downstream storm drain. A secondary overflow structure within cell 1 with rim elevation 337.25 feet will also provide conveyance during extremely large storm events or when the overflow structure or the flow control system is clogged. The outlet of the stormwater facility will be installed along the existing Sunset Lane then connect to an existing 12-inch storm drain system in Harrington Avenue NE that is 200 feet downstream of the facility. 2 REG IONAFAC ILITYTM_30%_V2/[INSERT DOCUMENT LOCATOR] COPYRIGHT[INSERT DATE SET BY SYSTEM]BY[CH2M HILL ENTITY]•COMPANY CONFIDENTIAL Sunset Community Low Impact Development Retrofit Project Sunset Terrace Regional Stormwater Facility Engineer's Estimate Schedule A-Storm Drain and Facility Improvements Item Sec. Item Description Quantity Units Unit Price Total Price No. No. 1 1-04 Minor Changes 1 Eq Eq.Adj. $ 15,000.00 2 1-09 Mobilization 1 LS LS $ 58,300.00 3 1-07 Temporary Traffic Control 1 LS 27,700.00 $ 27,700.00 4 1-07 Project Sign 1 LS 1,500.00 $ 1,500.00 5 1-11 Utility Potholing 10 EA 400.00 $ 4,000.00 6 1-10 Construction Surveying,staking,and As-built 1 LS 14,343.75 $ 14,343.75 7 2-01 Clearing and Grubbing 1 AC 9,000.00 $ 9,900.00 8 2-01 Roadside Cleanup 1 FA Eq.Adj. $ 5,000.00 9 2-02 Removal Existing Drainage Structure 3 EA 500.00 $ 1,500.00 10 2-02 Removal Existing Drainage Pie 160 LF 15.00 $ 2,400.00 11 2-03 Remove HMA Pavement 760 SY 7.00 $ 5,320.00 12 2-04 Remove Cement Concrete Sidewalk 130 SY 11.00 $ 1,430.00 13 2-02 Remove Cement Concrete Curb and Gutter 215 LF 5.00 $ 1,075.00 14 2-03 Roadway Excavation Including Haul 152 CY 25.00 $ 3,807.87 15 2-03 Facilities Excavation,Haul&Backfill 3,800 CY 19.80 $ 75,232.50 16 2-03 Gravel Borrow 1-n-cluding Haul 265 CY 35.42 $ 9,402.06 17 2-09 Shoring or Extra Excavation Class B 5,500 SF 1.00 $ 5,500.00 18 2-09 Removal and Replacement of Unsuitable Foundation Material 366 TON 100.00 $ 36,558.91 19 2-12 Construction Geotextile for Underground Drainage 1,500 SY 3.50 $ 5,250.00 20 4-04 Crushed Surfacing Base Course 183 TON 30.00 $ 5,488.33 21 5-04 HMA Cl.1/2-inch PG 64-22 Class B 247 TON 92.50 $ 22,863.26 22 5-04 Temporary Cold Mix Asphalt Concrete Patch 91 TON 100.00 $ 9,077.78 23 7-01 Underdrain 12-inches Diam 700 LF 50.00 $ 35,000.00 24 7-01 Drain Pipe 12-inch Diam 160 LF 40.00 $ 6,400.00 25 7-01 Mineral Aggregate Type 26 2,200 TON 28.00 $ 61,600.00 26 7-04 Corroguate Polyethylene Storm Sewer Pipe 12-inches Diam. 75 LF 52.56 $ 3,942.00 27 7-04 Corroguate Polyethylene Storm Sewer Pipe 184nches Diam. 835 LF 65.00 $ 54,275.00 28 7-04 Testing Storm Sewer Pipe 910 LF 2.00 $ 1,820.00 29 7-05 TV Inspection 910 LF 4.00 $ 3,640.00 30 7-05 Catch Basin Type 1 4 EA 1,400.00 $ 5,600.00 31 7-05 Catch Basin Type 2,481nch Diam. 12 EA 2,910.00 $ 34,920.00 32 7-05 Catch Basin Type 2,601nch Diam.Flow Control Structure 1 EA 5,820.00 $ 5,820.00 33 7-05 Catch Basin Type 2,481nch Diam.Debris Overflow Structure 1 EA 3,637.50 $ 3,637.50 34 1 7-05 Catch Basin Type 2,481nch Diam.Emergency Overflow Structure 1 EA 1,750.00 $ 1,750.00 35 7-05 Catch Basin Type 2,72inch Diam.Flow Splitter 1 EA 7,500.00 $ 7,500.00 36 7-05 Connection to Drainage Structure 5 EA 970.00 $ 4,850.0 37 7-19 8 Inch Clean Out 5 EA 630.00 $ 3,150.0 38 8-01 Temporary Erosion and Sediment/Water Pollution Control 1 LS 33,500.00 $ 33,500.0 45 8-02 Bioretention Soil&Plantings 1 LS 75,000.00 $ 75,000.00 46 8-02 Seeded Lawn Installation 4,500 SY 2.13 $ 9,585.00 47 8-04 Cement Concrete Traffic Curb and Gutter 215 LF 25.00 $ 5,375.00 48 8-14 Cement Concrete Sidewalk 130 SY 50.00 $ 6,500.00 49 8-21 Si na e&Striping 1 LS 2,500.00 $ 2,500.00 50 9-03 Cobbles 13 CY 110.00 $ 1,430.00 Subtotal Schedule A $ 688,443.96 Contingency 20.0% $ 137,688.79 Sub total $ 826,132.75 Sales Taxes 9.5% $ 78,482.61 Sub total $ 904,615.36 Escalation to Summer 2015 3.5% $ 31,661.54 Total $ 936,276.90 h:\proj\eng.est\SunsetTerrace_30%_Estimate_20140630_rwc 7/2/2014 at 2 54 PM 1 of 1 hAforms\fc016 Sunset Community Low Impact Development Retrofit Project Sunset Terrace Regional Stormwater Facility Engineer's Estimate Schedule A-Storm Drain and Facility Improvements Item Sec. Item Description Quantity Units Unit Price Total Price No. No. 1 1-04 Minor Changes 1 Eq. Eq.Adj. $ 15,000.00 Adj. 2 1-09 Mobilization 1 LS LS $ 58,300.00 3 1-07 Temporary Traffic Control 1 LS 27,700.00 $ 27,700.00 4 1-07 Project Sign 1 LS 1,500.00 $ 1,500.00 5 1-11 Utility Potholing 10 EA 400.00 $ 4,000.00 6 1-10 Construction Surveying,staking,and As-built 1 LS 14,343.75 $ 14,343.75 7 2-01 Clearing and Grubbing 1 AC 9,000.00 $ 9,900.00 8 2-01 Roadside Cleanup 1 FA Eq.Adj. $ 5,000.00 9 2-02 Removal Existing Drainage Structure 3 EA 500.00 $ 1,500.00 10 2-02 Removal Existing Drainage Pipe 160 LF 15.00 $ 2,400.00 11 2-03 Remove HMA Pavement 760 SY 7.00 $ 5,320.00 12 2-04 Remove Cement Concrete Sidewalk 130 SY 11.00 $ 1,430.00 13 2-02 Remove Cement Concrete Curb and Gutter 215 LF 5.00 $ 1,075.00 14 2-03 Roadway Excavation Including Haul 152 CY 25.00 $ 3,807.87 15 2-03 Facilities Excavation,Haul&Backfill 3,800 CY 19.80 $ 75,232.50 16 2-03 Gravel Borrow Including Haul 265 CY 35.42 $ 9,402.06 17 2-09 Shoring or Extra Excavation Class B 5,500 SF 1.00 $ 5,500.00 18 2-09 Removal and Replacement of Unsuitable Foundation Material 366 TON 100.00 $ 36,558.91 19 2-12 Construction Geotextile for Underground Drainage 1,500 SY 3.50 $ 5,250.00 20 4-04 Crushed Surfacing Base Course 183 TON 30.00 $ 5,488.33 21 5-04 HMA Cl.1/2-inch PG 64-22 Class B) 247 TON 92.50 $ 22,863.26 22 5-04 Temporary Cold Mix Asphaft Concrete Patch 91 TON 100.00 $ 9,077.78 23 7-01 Underdrain 12-inches Diam 700 LF 50.00 $ 35,000.00 24 7-01 Drain Pipe 12-inch Diam 160 LF 40.00 $ 6,400.00 25 7-01 Mineral Aggregate Type 26 2,200 TON 28.00 $ 61,600.00 26 7-04 Corroguate Polyethylene Storm Sewer Pipe 12-inches Diam. 75 LF 52.56 $ 3,942.00 27 7-04 Corroguate Polyethylene Storm Sewer Pipe 18-inches Diam. 835 LF 65.00 $ 54,275.00 28 7-04 Testing Storm Sewer Pipe 910 LF 2.00 $ 1,820.00 29 7-05 TV Inspection 910 LF 4.00 $ 3,640.00 30 7-05 Catch Basin Type 1 4 EA 1,400.00 $ 5,600.00 31 7-05 Catch Basin Type 2,481nch Diam. 12 EA 2,910.00 $ 34,920.00 32 7-05 Catch Basin Type 2,601nch Diam.Flow Control Structure 1 EA 5,820.00 $ 5,820.00 33 7-05 Catch Basin Type 2,481nch Diam.Debris Overflow Structure 1 EA 3,637.50 $ 3,637.50 34 7-05 Catch Basin Type 2,481nch Diam.Emergency Overflow Structure 1 EA 1,750.00 $ 1,750.00 35 7-05 Catch Basin Type 2,72inch Diam.Flow Splitter 1 EA 7,500.00 $ 7,500.00 36 7-05 Connection to Drainage Structure 5 EA 970.00 $ 4,850.00 37 7-19 81nch Clean Out 5 EA 630.00 $ 3,150.00 38 8-01 Temporary Erosion and Sediment/Water Pollution Control 1 LS 33,500.00 $ 33,500.00 45 8-02 Bioretention Soil&Plantings 1 LS 75,000.00 $ 75,000.00 46 8-02 Seeded Lawn Installation 4,500 SY 2.13 $ 9,585.00 47 8-04 Cement Concrete Traffic Curb and Gutter 215 LF 25.00 $ 5,375.00 48 8-14 ICement Concrete Sidewalk 130 SY 50.00 $ 6,500.00 49 8-21 1 Si na e&Striping 1 LS 2,500.001$ 2,500.00 50 9-03 JCobbles 13 CY 110.00 $ 1,430.00 Subtotal Schedule A $ 688,443.96 Contingency 20.0% $ 137,688.79 Sub total $ 826,132.75 Sales Taxes 9.5% $ 78,482.61 Sub total $ 904,615.36 Escalation to Summer2015 3.5% $ 31,661.54 Total $ 936,276.90 h:\proj\eng.est\SunsetTerrace_30%_Estimate_20140630_rwc 7/2/2014 at 2:54 PM 1 of 1 hAforms\fc016 Sunset Community Low Impact Development Retrofit Project Sunset Terrace Regional Stormwater Facility Engineer's Estimate Schedule A-Storm Drain and Facility Improvements Item Sec. Item Description Quantity Units Unit Price Total Price No. No. 1 1-04 Minor Changes 1 Eq. Eq.Adj. $ 15,000.00 Adj- - - _ - 2 1-09 Mobilization 1 LS LS $ 58,300.00 3 1-07 Temporary Traffic Control 1 LS 27,700.00 $ 27,700.00 4 1-07 Project Sign 1 LS 1,500.00 $ 1,500.00 5 1-11 Utility Potholing 10 EA 400.00 $ 4,000.00 6 1-10 Construction Surveying,staking,and As-built 1 LS 14,343.75 $ 14,343.75 7 2-01 Clearing and Grubbing 1 AC 9,000.00 $ 9,900.00 8 2-01 1 Roadside Cleanup 1 FA I Eq.Adj. $ 5,000.00 9 2-02 Removal Existing Drainage Structure 3 EA 500.00 $ 1,500.00 10 2-02 Removal Existing Drainage Pipe 160 LF 15.00 $ 2,400.00 11 2-03 Remove HMA Pavement 760 SY 7.00 $ 5,320.00 12 2-04 Remove Cement Concrete Sidewalk 130 SY 11.00 $ 1,430.00 13 2-02 Remove Cement Concrete Curb and Gutter 215 LF 5.00 $ 1,075.00 14 2-03 Roadway Excavation Including Haul 152 CY 25.00 $ 3,807.87 15 2-03 Facilities Excavation,Haul&Backfill 3,800 CY 19.80 $ 75,232.50 16 2-03 Gravel Borrow Including Haul 265 CY 35.42 $ 9,402.06 17 2-09 Shoring or Extra Excavation Class B 5,500 SF 1.00 $ 5,500.00 18 2-09 Removal and Replacement of Unsuitable Foundation Material 366 TON 100.00 $ 36,558.91 19 2-12 Construction Geotextile for Underground Drainage 1,500 SY 3.5 $ 5,250.00 20 4-04 Crushed Surfacing Base Course 183 TON 30.00 $ 5,488.33 21 5-04 HMA Cl.1/2-inch PG 64-22(Class B) 247 TON 92.50 $ 22,863.26 22 5-04 Temporary Cold Mix Asphalt Concrete Patch 91 TON 100.00 $ 9,077.78 23 7-01 Underdrain 12-inches Diam 700 LF 50.00 $ 35,000.00 24 7-01 Drain Pipe 12-inch Diam 160 LF 40.00 $ 6,400.00 25 7-01 Mineral Aggregate Type 26 2,200 TON 28.00 $ 61,600.00 26 7-04 Corroguate Polyethylene Storm Sewer Pipe 12-inches Diam. 75 LF 52.56 $ 3,942.00 27 7-04 Corroguate Polyethylene Storm Sewer Pipe 184nches Diam. 835 LF 65.00 $ 54,275.00 28 7-04 Testing Storm Sewer Pipe 910 LF 2.00 $ 1,820.00 29 7-05 TV Inspection 910 LF 4.00 $ 3,640.00 30 7-05 Catch Basin Type 1 4 EA 1,400.00 $ 5,600.00 31 7-05 Catch Basin Type 2,481nch Diam. 12 EA 2,910.00 $ 34,920.00 32 7-05 Catch Basin Type 2,601nch Diam.Flow Control Structure 1 EA 5,820.00 $ 5,820.00 33 7-05 Catch Basin Type 2,481nch Diam.Debris Overflow Structure 1 EA 3,637.50 $ 3,637.50 34 7-05 Catch Basin Type 2,481nch Diam.Emergency Overflow Structure 1 EA 1,750.00 $ 1,750.00 35 7-05 Catch Basin Type 2,72inch Diam.Flow Splitter 1 EA 7,500.00 $ 7,500.00 36 7-05 Connection to Drainage Structure 5 EA 970.00 $ 4,850.0 37 7-19 8 Inch Clean Out 5 EA 630.00 $ 3,150.0 38 8-01 Temporary Erosion and Sediment/Water Pollution Control 1 LS 33,500.00 $ 33,500.0 45 8-02 Bioretention Soil&Plantings 1 LS 75,000.00 $ 75,000.00 46 8-02 Seeded Lawn Installation 4,500 SY 2.13 $ 9,585.00 47 8-04 Cement Concrete Traffic Curb and Gutter 215 LF 25.00 $ 5,375.00 48 8-14 Cement Concrete Sidewalk 130 SY 50.00 $ 6,500.00 49 8-21 Si na e&Stri in 1 LS 2,500.00 $ 2,500.00 50 9-03 Cobbles 13 CY 110.00 $ 1,430.00 Subtotal Schedule A $ 688,443.96 Contingency 20.0% $ 137,688.79 Sub total $ 826,132.75 Sales Taxes 9.5% $ 78,482.61 Sub total $ 904,615.36 Escalation to Summer2015 3.5% $ 31,661.54 Total $ 936,276.90 h:\proj\eng.est\SunsetTerrace_30%_Estimate_20140630_rwc 7/2/2014 at 2:54 PM 1 of 1 h:\forms\fc016 Appendix B Subregional Facility Typical Sections 'A Zak t" Wj BE M01 ism AM r .1 IT ! , _ ' ! ._. _�. i f 4 s il WJ r . is ti vvl i� �AN..._. ` r _ qp 09 c 7 / W 3 Appendix C Harrington Avenue NE Typical Sections Job No. CF42MHILL. Sheet No. Job Name Date Su bject Computed By Checked By C I; CX (j A C*42MHILL. Job No, Sheet No, Job Name Date Subject Computed By Checked By r x r h t j ` s t S .. 3 In I SUBIECT By iN 1C? oil !d 4 11 PROJECT Na,,-a ... ,. 41l � ins a. ........ ..... _ _,., k ....... ...... ....~- -- , r , lift i • F r , _ w 1�� 1 3 ..� -...�_...,..,..r _ -_. lN on ! Fowl E", / pp a a I - F u e i a , E 3 r E £ � t Y i £ _ I I {€ 4�t c p vim__, .".... _ T_ - _ t it II as �a p • >', S UJ Ll Al - ., i i .,,E E �N-��k'T;+�d M s���? �.�r � � � F -......_"..._.. .• , -�..ma...____,.. _ H HI�..L.m Job No. , Sheet No. Job Name Date Subject Computed By Checked By 4; x t. s I' r' Appendix D WWHM Model Output and Input Sub-Regional Stormwater Facility Western Washington Hydrology Model PROJECT REPORT Project Name: RegFac_40WTG Site Address: City Renton Report Date 10/15/2012 Gage Seatac Data Start 1948/10/01 Data End 1998/09/30 Precip Scale: 1.00 WWHM3 Version: PREDEVELOPED LAND USE Name asin 1 Bypass: No GroundWater: No Pervious Land Use Acres A B, Lawn, Flat 1.54 C, Lawn, Flat 1.36 Impervious Land Use 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: 150ft. Bottom Width: 8ft. Depth : 1.45ft. Volume at riser head : 0.0397ft. Infiltration On Infiltration rate : 6 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 Infiltration Bed, Infiltration Bed, Pond Hydraulic Table Stage(ft) Area(acr) Volume(acr-£t) Dschrq(cfs) Infilt(cfs) 0.000 0.028 0.000 0.000 0.000 0.016 0.028 0.000 0.000 0.167 0.032 0.028 0.001 0.000 0.167 0.048 0.029 0.001 0.000 0.167 0.064 0.029 0.002 0.000 0.167 0.081 0.030 0.002 0.000 0.167 0.097 0.030 0.003 0.000 0.167 0.113 0.031 0.003 0.000 0.167 0.129 0.031 0.004 0.000 0.167 0.145 0.032 0.004 0.000 0.167 0.161 0.032 0.005 0.000 0.167 0.177 0.033 0.005 0.000 0.167 0.193 0.033 0.006 0.000 0.167 0.209 0.034 0.006 0.000 0.167 0.226 0.034 0.007 0.000 0.167 0.242 0.035 0.008 0.000 0.167 0.258 0.035 0.008 0.000 0.167 0.274 0.036 0.009 0.000 0.167 0.290 0.036 0.009 0.000 0.167 0.306 0.037 0.010 0.000 0.167 0.322 0.037 0.010 0.000 0.167 0.338 0.038 0.011 0.000 0.167 0.354 0.038 0.012 0.000 0.167 0.371 0.039 0.012 0.000 0.167 0.387 0.039 0.013 0.000 0.167 0.403 0.039 0.013 0.000 0.167 0.419 0.040 0.014 0.000 0.167 0.435 0.040 0.015 0.000 0.167 0.451 0.041 0.015 0.000 0.167 0.467 0.041 0.016 0.000 0.167 0.483 0.042 0.017 0.000 0.167 0.499 0.042 0.017 0.000 0.167 0.516 0.043 0.018 0.000 0.167 0.532 0.043 0.019 0.000 0.167 0.548 0.044 0.020 0.000 0.167 0.564 0.044 0.020 0.000 0.167 0.580 0.045 0.021 0.000 0.167 0.596 0.045 0.022 0.000 0.167 0.612 0.046 0.022 0.000 0.167 0.628 0.046 0.023 0.000 0.167 0.644 0.047 0.024 0.000 0.167 0.661 0.047 0.025 0.000 0.167 0.677 0.048 0.025 0.000 0.167 0.693 0.048 0.026 0.000 0.167 0.709 0.049 0.027 0.000 0.167 0.725 0.049 0.028 0.000 0.167 0.741 0.050 0.029 0.000 0.167 0.757 0.050 0.029 0.000 0.167 0.773 0.051 0.030 0.000 E 167 0.789 0.051 0.031 0.000 0.167 0.806 0.052 0.032 0.000 0.167 0.822 0.052 0.033 0.000 0.167 0.838 0.053 0.034 0.000 0.167 0.854 0.053 0.034 0.000 0.167 0.870 0.054 0.035 0.000 0.167 0.886 0.054 0.036 0.000 0.167 0.902 0.055 0.037 0.000 0.167 0.918 0.055 0.038 0.000 0.167 0.934 0.056 0.039 0.000 0.167 0.951 0.056 0.040 0.000 0.167 0.967 0.057 0.041 0.031 0.167 0.983 0.057 0.042 0.087 0.167 0.999 0.058 0.042 0.158 0.167 1.015 0.059 0.043 0.242 0.167 1.031 0.059 0.044 0.337 0.167 1.047 0.060 0.045 0.443 0.167 1.063 0.060 0.046 0.557 0.167 1.079 0.061 0.047 0.680 0.167 1.096 0.061 0.048 0.811 0.167 1.112 0.062 0.049 0.950 0.167 1.128 0.062 0.050 1.095 0.167 1.144 0.063 0.051 1.247 0.167 1.160 0.063 0.052 1.406 0.167 1.176 0.064 0.053 1.571 0.167 1.192 0.064 0.054 1.742 0.167 1.208 0.065 0.055 1.918 0.167 1.224 0.065 0.056 2.100 0.167 1.241 0.066 0.057 2.288 0.167 1.257 0.066 0.059 2.481 0.167 1.273 0.067 0.060 2.679 0.167 1.289 0.067 0.061 2.882 0.167 1.305 0.068 0.062 3.090 0.167 1.321 0.068 0.063 3.303 0.167 1.337 0.069 0.064 3.520 0.167 1.353 0.070 0.065 3.742 0.167 1.369 0.070 0.066 3.968 0.167 1.386 0.071 0.067 4.199 0.167 1.402 0.071 0.068 4.434 0.167 1.418 0.072 0.070 4.674 0.167 1.434 0.072 0.071 4.917 0.167 1.450 0.073 0.072 5.165 0.167 Name =nfiltration Bed Bottom Length: 150ft. Bottom Width : 70ft. 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 0.3 Material thickness of second layer : 0 Pour Space of material for second layer 0 Material thickness of third layer : 0 Pour Space of material for third layer 0 Infiltration On Infiltration rate : 1 .2 Infiltration saftey factor Discharge Structure Riser Height: 3.1 ft. Riser Diameter: 18 in. Orifice 1 Diameter: 1 . 4 in. Elevation: 0.5 ft. 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 0.241 0.000 0.000 0.000 0.039 0.241 0.003 0.000 0.292 0.078 0.241 0.006 0.000 0.292 0.117 0.241 0.008 0.000 0.292 0. 156 0.241 0.011 0.000 0.292 0.194 0.241 0.014 0.000 0.292 0.233 0.241 0.017 0.000 0.292 0.272 0.241 0.020 0.000 0.292 0.311 0.241 0.023 0.000 0.292 0.350 0.241 0.025 0.000 0.292 0.389 0.241 0.028 0.000 0.292 0.428 0.241 0.031 0.000 0.292 0.467 0.241 0.034 0.000 0.292 0.506 0.241 0.037 0.004 0.292 0.544 0.241 0.039 0.011 0 .292 0.583 0.241 0.042 0.015 0.292 0.622 0.241 0.045 0.018 0.292 0.661 0.242 0.048 0.021 0.292 0.700 0.242 0.051 0.023 0.292 0. 739 0.242 0.053 0.025 0.292 0.778 0.242 0.056 0.027 0.292 0.817 0.242 0.059 0.029 0.292 0.856 0.242 0.062 0.031 0.292 0.894 0.242 0.065 0.032 0.292 0.933 0.242 0.068 0.034 0.292 0.972 0.242 0.070 0.035 0.292 1.011 0.242 0.073 0.037 0.292 1.050 0.242 0.076 0.038 0.292 1.089 0.242 0.079 0.040 0.292 1.128 0.242 0.082 0.041 0.292 1.167 0.242 0.085 0.042 0.292 1.206 0.242 0.087 0.043 0.292 1.244 0.242 0.090 0.044 0.292 1.283 0.242 0.093 0.046 0.292 1.322 0.242 0.096 0.047 0.292 1.361 0.242 0.099 0.048 0.292 1.400 0.242 0.101 0.049 0.292 1.439 0.242 0.104 0.050 0.292 1.478 0.242 0.107 0.051 0.292 1.517 0.242 0.110 0.052 0.292 1.556 0.242 0.113 0.053 0.292 1.594 0.242 0.116 0.054 0.292 1.633 0.242 0.118 0.055 0.292 1.672 0.242 0.121 0.056 0.292 1.711 0.242 0.124 0.057 0.292 1.750 0.242 0.127 0.058 0.292 1.789 0.242 0.130 0.058 0.292 1.828 0.242 0.133 0.059 0.292 1.867 0.242 0.135 0.060 0.292 1.906 0.242 0.138 0.061 0.292 1.944 0.242 0.141 0.062 0.292 1.983 0.242 0.144 0.063 0.292 2.022 0.242 0.147 0.064 0.292 2.061 0.242 0.149 0.064 0.292 2.100 0.243 0.152 0.065 0.292 2.139 0.243 0.155 0.066 0.292 2.178 0.243 0.158 0.067 0.292 2.217 0.243 0.161 0.067 0.292 2.256 0.243 0.164 0.068 0.292 2.294 0.243 0.166 0.069 0.292 2.333 0.243 0.169 0.070 0.292 2.372 0.243 0.172 0.070 0.292 2.411 0.243 0.175 0.071 0.292 2.450 0.243 0.178 0.072 0.292 2.489 0.243 0.181 0.073 0.292 2.528 0.243 0.183 0.073 0.292 2.567 0.243 0.186 0.074 0.292 2.606 0.243 0.189 0.075 0.292 2.644 0.243 0.192 0.075 0.292 2.683 0.243 0.195 0.076 0.292 2.722 0.243 0.198 0.077 0.292 2.761 0.243 0.200 0.077 0.292 2.800 0.243 0.203 0.078 0.292 2.839 0.243 0.206 0.079 0.292 2.878 0.243 0.209 0.079 0.292 2.917 0.243 0.212 0.080 0.292 2.956 0.243 0.215 0.081 0.292 2.994 0.243 0.217 0.081 0.292 3.033 0.243 0.227 0.082 0.292 3.072 0.243 0.236 0.083 0.292 3.111 0.243 0.246 0.100 0.292 3.150 0.243 0.255 0.247 0.292 3.189 0.243 0.265 0.472 0.292 3.228 0.243 0.274 0.752 0.292 3.267 0.243 0.284 1.080 0.292 3.306 0.243 0.293 1.448 0.292 3.344 0.243 0.303 1.852 0.292 3.383 0.243 0.312 2.291 0.292 3.422 0.243 0.322 2.760 0.292 3.461 0.243 0.331 3.259 0.292 3.500 0.244 0.341 3.785 0.292 MITIGATED LAND USE ANALYSIS RESULTS Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.073005 5 year 0.124077 10 year 0.166614 25 year 0.231264 50 year 0.287981 100 year 0.352582 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.063809 5 year 0.123443 10 year 0.162299 25 year 0.206948 50 year 0.236238 100 year 0.262094 Yearly Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1950 0.085 0.052 1951 0.377 0.048 1952 0.163 0.071 1953 0.053 0.015 1954 0.037 0.014 1955 0.069 0.011 1956 0.097 0.070 1957 0.112 0.043 1958 0.095 0.060 1959 0.060 0.042 1960 0.063 0.017 1961 0.102 0.070 1962 0.087 0.010 1963 0.034 0.000 1964 0.064 0.000 1965 0.073 0.027 1966 0.049 0.018 1967 0.057 0.017 1968 0.136 0.057 1969 0.074 0.037 1970 0.058 0.036 1971 0.060 0.032 1972 0.064 0.020 1973 0.214 0.065 1974 0.050 0.023 1975 0.066 0.000 1976 0.115 0.065 1977 0.065 0.018 1978 0.024 0.010 1979 0.070 0.057 1980 0.030 0.022 1981 0.090 0.052 1982 0.077 0.037 1983 0.163 0.123 1984 0.065 0.053 1985 0.064 0.012 1986 0.034 0.037 1987 0.122 0.082 1988 0.107 0.076 1989 0.041 0.003 1990 0.029 0.000 1991 0.262 0.491 1992 0.204 0.221 1993 0.058 0.034 1994 0.046 0.000 1995 0.022 0.000 1996 0.063 0.034 1997 0.203 0.074 1998 0.141 0.239 1999 0.071 0.024 Ranked Yearly Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.3767 0.4907 2 0.2619 0.2392 3 0.2141 0.2214 4 0.2035 0.1234 5 0.2033 0.0820 6 0.1633 0.0763 7 0.1631 0.0738 8 0.1408 0.0713 9 0.1356 0.0698 10 0.1219 0.0697 11 0.1154 0.0654 12 0.1116 0.0652 13 0.1074 0.0599 14 0.1022 0.0574 15 0.0973 0.0570 16 0.0946 0.0531 17 0.0902 0.0520 18 0.0873 0.0517 19 0.0852 0.0476 20 0.0769 0.0426 21 0.0741 0.0418 22 0.0735 0.0371 23 0.0709 0.0370 24 0.0700 0.0370 25 0.0686 0.0357 26 0.0660 0.0341 27 0.0652 0.0341 28 0.0645 0.0321 29 0.0644 0.0269 30 0.0643 0.0241 31 0.0637 0.0228 32 0.0633 0.0218 33 0.0632 0.0200 34 0.0600 0.0183 35 0.0597 0.0175 36 0.0584 0.0174 37 0.0581 0.0170 38 0.0566 0.0147 39 0.0532 0.0144 40 0.0501 0.0124 41 0.0489 0.0114 42 0.0456 0.0104 43 0.0412 0.0102 44 0.0373 0.0026 45 0.0340 0.0000 46 0.0337 0.0000 47 0.0302 0.0000 48 0.0292 0.0000 49 0.0244 0.0000 50 0.0219 0.0000 POC #1 Facility FAILED duration standard for 1+ flows. Flow(CFS) Predev Dev Percentage Pass/Fail 0.0365 2145 392 18 Pass 0.0390 1734 340 19 Pass 0.0416 1543 312 20 Pass 0.0441 1267 286 22 Pass 0.0467 1065 260 24 Pass 0.0492 955 233 24 Pass 0.0517 807 199 24 Pass 0.0543 690 172 24 Pass 0.0568 618 156 25 Pass 0.0594 512 132 25 Pass 0.0619 467 116 24 Pass 0.0644 393 90 22 Pass 0.0670 339 73 21 Pass 0.0695 312 59 18 Pass 0.0721 274 50 18 Pass 0.0746 240 37 15 Pass 0.0771 223 31 13 Pass 0.0797 182 20 10 Pass 0.0822 157 19 12 Pass 0.0848 137 17 12 Pass 0.0873 116 17 14 Pass 0.0898 107 17 15 Pass 0.0924 94 17 18 Pass 0.0949 86 17 19 Pass 0.0975 77 17 22 Pass 0.1000 67 17 25 Pass 0.1025 63 17 26 Pass 0.1051 58 17 29 Pass 0.1076 54 17 31 Pass 0.1102 49 17 34 Pass 0.1127 40 17 42 Pass 0.1152 38 17 44 Pass 0.1178 37 17 45 Pass 0.1203 36 16 44 Pass 0.1229 35 16 45 Pass 0.1254 33 16 48 Pass 0.1279 32 16 50 Pass 0.1305 32 16 50 Pass 0.1330 30 16 53 Pass 0.1356 26 14 53 Pass 0.1381 24 13 54 Pass 0.1407 18 13 72 Pass 0.1432 16 12 75 Pass 0.1457 16 12 75 Pass 0.1483 16 12 75 Pass 0.1508 16 12 75 Pass 0.1534 16 12 75 Pass 0.1559 16 12 75 Pass 0.1584 16 10 62 Pass 0.1610 15 9 60 Pass 0.1635 12 9 75 Pass 0.1661 12 9 75 Pass 0.1686 10 9 90 Pass 0.1711 10 9 90 Pass 0.1737 9 8 88 Pass 0.1762 9 8 88 Pass 0.1788 9 8 88 Pass 0.1813 9 8 88 Pass 0.1838 9 8 88 Pass 0.1864 8 7 87 Pass 0.1889 8 7 87 Pass 0.1915 8 7 87 Pass 0.1940 8 7 87 Pass 0.1965 8 7 87 Pass 0.1991 8 7 87 Pass 0.2016 8 7 87 Pass 0.2042 7 7 100 Pass 0.2067 7 6 85 Pass 0.2092 6 6 100 Pass 0.2118 5 6 120 Fail 0.2143 5 5 100 Pass 0.2169 5 5 100 Pass 0.2194 5 4 80 Pass 0.2219 5 3 60 Pass 0.2245 5 3 60 Pass 0.2270 5 3 60 Pass 0.2296 5 3 60 Pass 0.2321 5 3 60 Pass 0.2346 5 3 60 Pass 0.2372 5 3 60 Pass 0.2397 5 3 60 Pass 0.2423 5 3 60 Pass 0.2448 5 3 60 Pass 0.2473 4 3 75 Pass 0.2499 3 3 100 Pass 0.2524 3 2 66 Pass 0.2550 3 2 66 Pass 0.2575 3 2 66 Pass 0.2600 2 2 100 Pass 0.2626 2 2 100 Pass 0.2651 2 2 100 Pass 0.2677 1 2 200 Fail 0.2702 1 2 200 Fail , 0.2727 1 2 200 Fail 0.2753 1 2 200 Fail 0.2778 1 2 200 Fail 0.2804 1 2 200 Fail 0.2829 1 2 200 Fail 0.2854 1 2 200 Fail 0.2880 1 2 200 Fail The development has an increase in flow durations from 1/2 predeveloped 2 year flow to the 2 year flow + or more than a 10% increase from the 2 year to the 50 year flow. Water Quality BW Flow and Volume for POC 1. On-line facility volume: 0.3421 acre-feet On-line facility target flow: 0.01 cfs. Adjusted for 15 min: 0.3682 cfs. Off-line facility target flow: 0.1618 cfs. Adjusted for 15 min: 0.1829 cfs. Perind and Impind 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. 1 uL£NMiU:i� .,..'•�� ....�..•_ Gerwt,/Unhx j c _ ' e "` � fie-•.„tom +�i ross � r,.,, .gm .eMw w,ow j I��T 1 ypy Deis t)nkea {i„1nwM,No��M fHMa� • 1 � bnm.o .. #vnGw i pH 1�lt Rw-1 1015,2012 1:51 PIA 7� �.. � ~ ` .... DIA mwewua+r, lw+w rh.�f )ul,ac i ob �7 My MMr✓s l`4 YIM� 'kM �.'µ n: A � t r � - � 3�zbYa.m uka,f`uSS`w§7 4aV. i � •se3-mxn�' iW1SjZOte 1:5/PM Harrington Avenue NE Renton Sunset Stormwater Retrofit/LID Project Renton Sunset City of Renton Table 2A Tributary Area Breakdown Location: Renton Highlands, Renton, WA Sub-Basin: Harrington Avenuue NE (Eastside); NE 12th St to NE 16th St Project Sub-Total Sub-Total Land Use site (SF) (Ac) Impervious Roadway/Parking 17424 17424 0.40 Roofs 20865 20865 0.48 Driveways 11892 11892 0.27 Pond Sidewalk 7405 7405 0.17 Pervious Till Landscape Outwash Landscape 105982 105982 2.43 Saturated Landscape Green Roof Pervious Pavement Sub-total 163568 3.76 Total 163568 3.76 Western Washington Hydrology Model PROJECT REPORT Project Name: NH-E-1011 Site Address: Renton Highlands City Renton Report Date 10/29/2012 Gage Seatac Data Start 1948/10/01 Data End 1998/09/30 Precip Scale: 1 .00 WWHM3 Version: PREDEVELOPED LAND USE Name Basin 1 Bypass: No GroundWater: No Pervious Land Use Acres A B, Lawn, Mod 2.44 Impervious Land Use Acres ROADS FLAT 0.57 ROOF TOPS FLAT 0.48 DRIVEWAYS FLAT 0.27 Element Flows To: Surface Interflow Groundwater Name Basin 1 Bypass: No GroundWater: No Pervious Land Use Acres A B, Lawn, Mod 2.44 Impervious Land Use Acres ROADS FLAT 0.57 ROOF TOPS FLAT 0.48 DRIVEWAYS FLAT 0.27 Element Flows To: Surface Interflow Groundwater Swalel, Swalel, Name Swalel Bottom Length: 440ft. Bottom Width: 3.5ft. Depth : 1.5ft. Volume at riser head : 0.1184ft. Infiltration On Infiltration rate : 1.2 Infiltration saftey factor 1 Wetted surface area On Side slope 1: 3 To 1 Side slope 2: 3 To 1 Side slope 3: 3 To 1 Side slope 4: 3 To 1 Discharge Structure Riser Height: 1.45 ft. Riser Diameter: 10000 in. Orifice 1 Diameter: 1.2 in. Elevation: 0.15 ft. Element Flows To: Outlet 1 Outlet 2 Pond Hydraulic Table Stage(ft) Area(acr) Volume(acr-ft) Dschrg(cfs) Infilt(cfs) 0.000 0.035 0.000 0.000 0.000 0.017 0.036 0.001 0.000 0.044 0.033 0.037 0.001 0.000 0.045 0.050 0.038 0.002 0.000 0.047 0.067 0.039 0.002 0.000 0.048 0.083 0.040 0.003 0.000 0.049 0.100 0.041 0.004 0.000 0.051 0.117 0.042 0.005 0.000 0.052 0.133 0.044 0.005 0.000 0.053 0.150 0.045 0.006 0.000 0.054 0.167 0.046 0.007 0.005 0.056 0.183 0.047 0.008 0.007 0.057 0.200 0.048 0.008 0.008 0.058 0.217 0.049 0.009 0.010 0.060 0.233 0.050 0.010 0.011 0.061 0.250 0.051 0.011 0.012 0.062 0.267 0.052 0.012 0.013 0.064 0.283 0.053 0.012 0.014 0.065 0.300 0.054 0.013 0.015 0.066 0.317 0.055 0.014 0.'015 0.068 0.333 0.056 0.015 0.016 0.069 0.350 0.057 0.016 0.017 0.070 0.367 0.058 0.017 0.018 0.071 0.383 0.059 0.018 0.018 0.073 0.400 0.060 0.019 0.019 0.074 0.417 0.061 0.020 0.020 0.075 0.433 0.062 0.021 0.020 0.077 0.450 0.063 0.022 0.021 0.078 0.467 0.064 0.023 0.021 0.079 0.483 0.065 0.024 0.022 0.081 0.500 0.066 0.025 0.022 0.082 0.517 0.067 0.026 0.023 0.083 0.533 0.068 0.028 0.023 0.085 0.550 0.069 0.029 0.024 0.086 0.567 0.070 0.030 0.024 0.087 0.583 0.071 0.031 0.025 0.089 0.600 0.072 0.032 0.025 0.090 0.617 0.073 0.033 0.026 0.091 0.633 0.074 0.035 0.026 0.093 0.650 0.075 0.036 0.027 0.094 0.667 0.076 0.037 0.027 0.095 0.683 0.077 0.039 0.028 0.097 0.700 0.079 0.040 0.028 0.098 0.717 0.080 0.041 0.028 0.099 0.733 0.081 0.042 0.029 0.100 0.750 0.082 0.044 0.029 0.102 0.767 0.083 0.045 0.030 0.103 0.783 0.084 0.047 0.030 0.104 0.800 0.085 0.048 0.030 0.106 0.817 0.086 0.049 0.031 0.107 0.833 0.087 0.051 0.031 0.108 0.850 0.088 0.052 0.032 0.110 0.867 0.089 0.054 0.032 0.111 0.883 0.090 0.055 0.032 0.112 0.900 0.091 0.057 0.033 0.114 0.917 0.092 0.058 0.033 0.115 0.933 0.093 0.060 0.033 0.116 0.950 0.094 0.061 0.034 0.118 0.967 0.095 0.063 0.034 0.119 0.983 0.096 0.065 0.035 0.120 1.000 0.097 0.066 0.035 0.122 1.017 0.098 0.068 0.035 0.123 1.033 0.099 0.069 0.036 0.124 1.050 0.100 0.071 0.036 0.126 1.067 0.101 0.073 0.036 0.127 1.083 0.103 0.074 0.037 0.128 1.100 0.104 0.076 0.037 0.130 1.117 0.105 0.078 0.037 0.131 1.133 0.106 0.080 0.038 0.132 1.150 0.107 0.081 0.038 0.134 1.167 0.108 0.083 0.038 0.135 1.183 0.109 0.085 0.038 0.136 1.200 0.110 0.087 0.039 0.138 1.217 0.111 0.089 0.039 0.139 1.233 0.112 0.091 0.039 0.140 1.250 0.113 0.092 0.040 0.142 1.267 0.114 0.094 0.040 0.143 1.283 0.115 0.096 0.040 0.145 1.300 0.116 0.098 0.041 0.146 1.317 0.117 0.100 0.041 0.147 1.333 0.118 0.102 0.041 0.149 1.350 0.119 0.104 0.041 0.150 1.367 0.120 0.106 0.042 0.151 1.383 0.121 0.108 0.042 0.153 1.400 0.122 0.110 0.042 0.154 1.417 0.124 0.112 0.043 0.155 1.433 0.125 0.114 0.043 0.157 1.450 0.126 0.116 0.043 0.158 1.467 0.127 0.118 17.51 0.159 1.483 0.128 0.121 49.44 0.161 1.500 0.129 0.123 90.78 0.162 1.517 0.130 0.125 139.7 0.163 MITIGATED LAND USE ANALYSIS RESULTS Flow Frequency Return Periods for Predeveloped POC #1 Return Period Flow(cfs) 2 year 0.340539 5 year 0.429867 10 year 0.491768 25 year 0.573209 50 year 0.636466 100 year 0.701891 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.035036 5 year 0.056828 10 year 0.075938 25 year 0.106512 50 year 0.134727 100 year 0.168317 Yearly Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1950 0.237 0.036 1951 0.535 0.038 1952 0.292 0.042 1953 0.206 0.028 1954 0.187 0.029 1955 0.227 0.029 1956 0.236 0.041 1957 0.239 0.035 1958 0.257 0.038 1959 0.234 0.034 1960 0.193 0.031 1961 0.232 0.039 1962 0.237 0.029 1963 0.202 0.026 1964 0.198 0.026 1965 0.235 0.030 1966 0.205 0.031 1967 0.203 0.029 1968 0.304 0.039 1969 0.344 0.031 1970 0.185 0.033 1971 0.202 0.032 1972 0.197 0.030 1973 0.371 0.043 1974 0.185 0.030 1975 0.202 0.026 1976 0.266 0.039 1977 0.183 0.030 1978 0.236 0.029 1979 0.306 0.036 1980 0.303 0.028 1981 0.249 0.036 1982 0.278 0.032 1983 0.378 0.042 1984 0.280 0.036 1985 0.212 0.029 1986 0.200 0.033 1987 0.249 0.043 1988 0.350 0.042 1989 0.169 0.028 1990 0.212 0.024 1991 0.416 0.413 1992 0.371 0.228 1993 0.209 0.032 1994 0.145 0.028 1995 0.173 0.023 1996 0.216 0.032 1997 0.323 0.159 1998 0.290 0.087 1999 0.264 0.030 Ranked Yearly Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.5353 0.4128 2 0.4162 0.2284 3 0.3782 0.1589 4 0.3711 0.0869 5 0.3706 0.0427 6 0.3501 0.0426 7 0.3439 0.0423 8 0.3225 0.0422 9 0.3063 0.0417 10 0.3039 0.0406 11 0.3026 0.0394 12 0.2922 0.0389 13 0.2903 0.0389 14 0.2803 0.0383 15 0.2776 0.0377 16 0.2656 0.0362 17 0.2639 0.0361 18 0.2571 0.0359 19 0.2491 0.0359 20 0.2487 0.0346 21 0.2388 0.0338 22 0.2368 0.0335 23 0.2365 0.0333 24 0.2362 0.0325 25 0.2357 0.0324 26 0.2354 0.0324 27 0.2340 0.0318 28 0.2324 0.0309 29 . 0.2265 0.0308 30 0.2155 0.0306 31 0.2121 0.0305 32 0.2115 0.0304 33 0.2089 0.0300 34 0.2062 0.0298 35 0.2053 0.0296 36 0.2028 0.0293 37 0.2021 0.0293 38 0.2021 0.0290 39 0.2020 0.0288 40 0.2005 0.0286 41 0.1981 0.0286 42 0.1970 0.0284 43 0.1934 0.0279 44 0.1869 0.0277 45 0.1852 0.0276 46 0.1852 0.0263 47 0.1827 0.0262 48 0.1731 0.0260 49 0.1687 0.0239 50 0.1446 0.0233 Per1nd and Imp1nd 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. Fk Edit V Hdp _........._._..... O a id] �' ► SCENARIOS :Facility Nama t-FrediQ.loPe _1". 0u1107 0.U0Z OuMe13___ Oawnstrenm Co...oi.ns f P',I,,1_:xed '.�� Feeiliy Type La 31 "'id Ft FMFM iS s"lu�l*,wvnxQF rm Feality Betlom El—tum(to p.- �� ('�_` Faaliy Dm nsmns ' -- Bottom Length pt1 y Outlet Structure k FLsar Height(ttl 1 m, Bartow Width(fq " .45 Eaecwe Depth M) t=J (dWdd : Leh Side SlopeNM Piset Typa(Flgl -y; Bottom Side Slope Notch Rigln Side Slop. Tap Side Slope(HM, „ ....__... ._....._. Faa111y Dimension Drngran --- --- - O dice Diameter Height OM— ' Iidiltrabon yEg Number pn). (Ft) (da) Measured edlaatlon Rare 1�2�""3 1 1='m�mM,!O 15 -;"' 11.114394 Retlucuan FacmIfInfilClacto!J (j—^°-; 2 n use Weeed Bartace Nea FES 3 0 .:. ;�,. g Tatat Volume Infiltrawa(iuse4� 159.'i2 To al Volume Through 3559 Pond Voume w Ricer tread .118 M.-Elements pondl—ent Total V.I.m.Th—gh '72.78 E petcemlrtiluated 9z,5 Shaw Pond Table t0oen Table ✓ _ � -� _ �> Use-de ante? r3 x ti 10/2912( 236 PM Renton Sunset Stormwater Retrofit/LID Project Renton Sunset City of Renton Table 2B Tributary Area Breakdown Location: Renton Highlands, Renton, WA Sub-Basin: Harrington Avenuue NE (Westside); NE 12th St to NE 16th St Project Sub-Total Sub-Total Land Use site (SF) (Ac) Impervious Roadway/Parking 24829 24829 0.57 Roofs Driveways Pond Pervious Till Landsca e Outwash Landscape Saturated Landscape Green Roof Pervious Pavement Sub-total 24829 0.57 Total 24829 0.57 Western Washington Hydrology Model PROJECT REPORT Project Name: NH-W-1011 Site Address: Renton Highlands City Renton Report Date 10/29/2012 Gage Seatac Data Start 1948/10/01 Data End 1998/09/30 Precip Scale: 1 .00 WWHM3 Version: PREDEVELOPED LAND USE Name 3asin 1 Bypass: No GroundWater: No Pervious Land Use Acres Impervious Land Use Acres ROADS FLAT 0.57 Element Flows To: Surface Interflow Groundwater Name 3asin 1 Bypass: No GroundWater: No Pervious Land Use Acres Impervious Land Use Acres ROADS FLAT 0.57 Element Flows To: Surface Interflow Groundwater Swalel, Swalel, Name Swalel Bottom Length: 150ft. Bottom Width: 5.5ft. Depth : 1.5ft. Volume at riser head : 0.0517ft. Infiltration On Infiltration rate 1.2 Infiltration saftey factor 1 Wetted surface area On Side slope 1: 3 To 1 Side slope 2: 3 To 1 Side slope 3: 3 To 1 Side slope 4: 3 To 1 Discharge Structure Riser Height: 1.45 ft. Riser Diameter: 10000 in. Orifice 1 Diameter: 1 in. Elevation: 0.15 ft. Element Flows To: Outlet 1 Outlet 2 Pond Hydraulic Table Stage(ft) Area(acr) Volume(acr-ft) Dschrg(cfs) Infilt(cfs) 0.000 0.019 0.000 0.000 0.000 0.017 0.019 0.000 0.000 0.023 0.033 0.020 0.001 0.000 0.024 0.050 0.020 0.001 0.000 0.024 0.067 0.020 0.001 0.000 0.025 0.083 0.021 0.002 0.000 0.025 0.100 0.021 0.002 0.000 0.026 0.117 0.021 0.002 0.000 0.026 0.133 0.022 0.003 0.000 0.027 0.150 0.022 0.003 0.000 0.027 0.167 0.023 0.003 0.003 0.027 0.183 0.023 0.004 0.005 0.028 0.200 0.023 0.004 0.006 0.028 0.217 0.024 0.005 0.007 0.029 0.233 0.024 0.005 0.008 0.029 0.250 0.024 0.005 0.008 0.030 0.267 0.025 0.006 0.009 0.030 0.283 0.025 0.006 0.010 0.031 0.300 0.025 0.007 0.010 0.031 0.317 0.026 0.007 0.011 0.032 0.333 0.026 0.008 0.011 0.032 0.350 0.027 0.008 0.012 0.033 0.367 0.027 0.008 0.012 0.033 0.383 0.027 0.009 0.013 0.034 0.400 0.028 0.009 0.013 0.034 0.417 0.028 0.010 0.014 0.034 0.433 0.028 0.010 0.014 0.035 0.450 0.029 0.011 0.014 0.035 0.467 0.029 0.011 0.015 0.036 0.483 0.029 0.012 0.015 0.036 0.500 0.030 0.012 0.016 0.037 0.517 0.030 0.013 0.016 0.037 0.533 0.031 0.013 0.016 0.038 0.550 0.031 0.014 0.017 0.038 0.567 0.031 0.014 0.017 0.039 0.583 0.032 0.015 0.017 0.039 0.600 0.032 0.015 0.018 0.040 0.617 0.032 0.016 0.018 0.040 0.633 0.033 0.016 0.018 0.041 0.650 0.033 0.017 0.019 0.041 0.667 0.034 0.017 0.019 0.042 0.683 0.034 0,018 0.019 0.042 0.700 0.034 0.019 0.019 0.043 0.717 0.035 0.019 0.020 0.043 0.733 0.035 0.020 0.020 0.044 0.750 0.035 0.020 0.020 0.044 0.767 0.036 0.021 0.021 0.044 0.783 0.036 0.022 0.021 0.045 0.800 0.037 0.022 0.021 0.045 0.817 0.037 0.023 0.021 0.046 0.833 0.037 0.023 0.022 0.046 0.850 0.038 0.024 0.022 0.047 0.867 0.038 0.025 0.022 0.047 0.883 0.039 0.025 0.022 0.048 0.900 0.039 0.026 0.023 0.048 0.917 0.039 0.027 0.023 0.049 0.933 0.040 0.027 0.023 0.049 0.950 0.040 0.028 0.023 0.050 0.967 0.040 0.029 0.024 0.050 0.983 0.041 0.029 0.024 0.051 1.000 0.041 0.030 0.024 0.051 1.017 0.042 0.031 0.024 0.052 1.033 0.042 0.031 0.025 0.052 1.050 0.042 0.032 0.025 0.053 1.067 0.043 0.033 0.025 0.053 1.083 0.043 0.033 0.025 0.054 1.100 0.043 0.034 0.026 0.054 1.117 0.044 0.035 0.026 0.055 1.133 0.044 0.036 0.026 0.055 1.150 0.045 0.036 0.026 0.056 1.167 0.045 0.037 0.026 0.056 1.183 0.045 0.038 0.027 0.057 1.200 0.046 0.039 0.027 0.057 1.217 0.046 0.039 0.027 0.058 1.233 0.047 0.040 0.027 0.058 1.250 0.047 0.041 0.028 0.059 1.267 0.047 0.042 0.028 0.059 1.283 0.048 0.043 0.028 0.060 1.300 0.048 0.043 0.028 0.060 1.317 0.049 0.044 0..028 0.061 1.333 0.049 0.045 0.029 0.061 1.350 0.049 0.046 0.029 0.062 1.367 0.050 0.047 0.029 0.062 1.383 0.050 0.047 0.029 0.063 1.400 0.051 0.048 0.029 0.063 1.417 0.051 0.049 0.030 0.064 1.433 0.051 0.050 0.030 0.064 1.450 0.052 0.051 0.030 0.065 1.467 0.052 0.052 17.49 0.065 1.483 0.053 0.053 49.42 0.066 1.500 0.053 0.053 90.77 0.066 1.517 0.053 0.054 139.7 0.067 MITIGATED LAND USE ANALYSIS RESULTS Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.14245 5 year 0.173159 10 year 0.192962 25 year 0.217707 50 year 0.236137 100 year 0.254331 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.01941 5 year 0.037704 10 year 0.056135 25 year 0.089322 50 year 0.123329 100 year 0.167411 Yearly Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1950 0.102 0.017 1951 0.145 0.016 1952 0.098 0.054 1953 0.089 0.013 1954 0.080 0.014 1955 0.095 0.013 1956 0.102 0.040 1957 0.098 0.017 1958 0.111 0.018 1959 0.101 0.016 1960 0.078 0.015 1961 0.096 0.047 1962 0.084 0.014 1963 0.087 0.012 1964 0.083 0.012 1965 0.098 0.014 1966 0.088 0.015 1967 0.087 0.013 1968 0.131 0.018 1969 0.148 0.014 1970 0.079 0.016 1971 0.087 0.015 1972 0.085 0.014 1973 0.121 0.034 1974 0.079 0.014 1975 0.087 0.012 1976 0.115 0.035 1977 0.079 0.014 1978 0.102 0.013 1979 0.132 0.018 1980 0.131 0.013 1981 0.107 0.018 1982 0.120 0.015 1983 0.163 0.109 . 1984 0.121 0.017 1985 0.091 0.014 1986 0.087 0.016 1987 0.105 0.100 1988 0.151 0.088 1989 0.073 0.013 1990 0.091 0.011 1991 0.163 0.154 1992 0.153 0.137 1993 0.090 0.015 1994 0.062 0.013 1995 0.075 0.010 1996 0.093 0.015 1997 0.107 0.089 1998 0.104 0.062 1999 0.114 0.014 Ranked Yearly Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 0.1631 0.1541 2 0.1629 0.1365 3 0.1530 0.1087 4 0.1511 0.1003 5 0.1484 0.0885 6 0.1451 0.0879 7 0.1322 0.0624 8 0.1312 0.0537 9 0.1306 0.0470 10 0.1210 0.0400 11 0.1208 0.0347 12 0.1198 0.0344 13. 0.1146 0.0185 14 0.1138 0.0184 15 0.1110 0.0177 16 0.1074 0.0176 17 0.1071 0.0174 18 0.1046 0.0172 19 0.1041 0.0171 20 0.1020 0.0165 21 0.1019 0.0162 22 0.1017 0.0160 23 0.1010 0.0158 24 0.0982 0.0154 25 0.0981 0.0153 26 0.0980 0.0153 27 0.0962 0.0152 28 0.0948 0.0151 29 0.0930 0.0150 30 0.0913 0.0144 31 0.0905 0.0143 32 0.0902 0.0142 33 0.0890 0.0141 34 0.0879 0.0140 35 0.0872 0.0140 36 0.0872 0.0139 37 0.0871 0.0139 38 0.0871 0.0137 39 0.0865 0.0135 40 0.0850 0.0134 41 0.0844 0.0133 42 0.0826 0.0131 43 0.0800 0.0130 44 0.0794 0.0130 45 0.0793 0.0129 46 0.0788 0.0122 47 0.0775 0.0120 48 0.0747 0.0119 49 0.0727 0.0108 50 0.0624 0.0104 Per1nd and Impind 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, e�_ther 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. RIF Y,!-.. Mklp o ��F ® � 12 _ . $4 i; SCENAPt05 - F.aliy Hem. :Swatel -`' r Ftedevelope 11iW61T Qutlot Y"" ' Outlet 3 Oownsoeam Connearons C p Ip 6 M E}aa d Facility Type Tm_oeroidN annd:..... .�.i_ .....i. Ar.90 OA--- ' RUr cenann l�e1Ck Fend 17 xt Yc tiC Fadliy Bottom Elavabo (tt) .11 ' Fndliy Dimenstoas • '1 Outlet Slruciure ....... ....... Peer Heigh(1p Bottom Width t� ' 1 -_-6,I Sort—q 'a Depth(IQ r 's 5 0000":"� E"etm. Riser � WtmL'i Left-ide Slope MM Riser TYPe Fiat "`I ___. - .�------ S de Slope Natch Ri MSide Slope Top Side Slop.�:H V, , Facii y Dimension Dtagrem ............... ... ......r Orifice Diameter Height DWI- Willration :^(ES Number On) (Ft) (ds) (Measured lofftog n Pate .3 i 1 �':`j 1 (j mm-^?',p 15 0.03052 ReduC.h Facto OdlMador) F1`-:j .use waited Surface Aee PES -'i 3 ........... Total Volume Infilaeted(arue4p 67 919 Total Volume Through 6.207 Pond Volume ad Riser Head .06, j �—�-Nave lamems Total Volumo Th—gh ?q13 Pundlncremen! ;p,lp I]j Peraminlihreted 61.63 Show Pond Table *L'n To ale 9 _�-. ........._ 2 � _ �_. i 10/29/2(2:32 PM Renton Sunset Stormwater Retrofit/LID Project Renton Sunset City of Renton Table 3A Tributary Area Breakdown Location: Renton Highlands, Renton, WA Sub-Basin: Harrington Avenuue NE (Eastside of street); NE 10th St to NE 12th St Project Sub-Total Sub-Total Land Use site (SF) (Ac) Impervious Roadway/Parking 15246 15246 0.35 Roofs 12197 1 12197 0.28 Driveways 13068 13068 0.30 Pond Sidewalk 1742 1742 0.04 Pervious Till Landscape 36590 36590 0.84 Outwash Landscape Saturated Landscape Green Roof Pervious Pavement Sub-total 78844 1.81 Total 78844 1.81 Western Washington Hydrology Model PROJECT REPORT Project Name: MH-EW-1011 Site Address: Renton Highlands City Renton Report Date 10/29/2012 Gage Seatac Data Start 1948/10/01 Data End 1998/09/30 Precip Scale: 1 .00 WWHM3 Version: PREDEVELOPED LAND USE Name Basin 1 Bypass: No GroundWater: No Pervious Land Use Acres A B, Lawn, Mod 0.84 Impervious Land Use Acres ROADS FLAT 0.39 ROOF TOPS FLAT 0.28 DRIVEWAYS FLAT 0.3 Element Flows To: Surface Interflow Groundwater Name Basin 1 Bypass: No GroundWater: No Pervious Land Use Acres A B, Lawn, Mod .84 Impervious Land Use Acres ROADS FLAT 0.39 ROOF TOPS FLAT 0.28 DRIVEWAYS FLAT 0.3 Element Flows To: Surface Interflow Groundwater Swalel, Swalel, Name Swalel Bottom Length: 170ft. Bottom Width: 5ft. Depth : 1.5ft. Volume at riser head : 0.0554ft. Infiltration On Infiltration rate : 0 Infiltration saftey factor 1 Wetted surface area On Side slope 1: 3 To 1 Side slope 2: 3 To 1 Side slope 3: 3 To 1 Side slope 4: 3 To 1 Discharge Structure Riser Height: 1.45 ft. Riser Diameter: 10000 in. Orifice 1 Diameter: 3 in. Elevation: 0.15 ft. Element Flows To: Outlet 1 Outlet 2 Pond Hydraulic Table Stage(ft) Area(acr) Volume(acr-ft) Dschrg(cfs) infilt(cfs) 0.000 0.020 0.000 0.000 0.000 0.017 0.020 0.000 0.000 0.000 0.033 0.020 0.001 0.000 0.000 0.050 0.021 0.001 0.000 0.000 0.067 0.021 0.001 0.000 0.000 0.083 0.022 0.002 0.000 0.000 0.100 0.022 0.002 0.000 0.000 0.117 0.022 0.002 0.000 0.000 0.133 0.023 0.003 0.000 0.000 0.150 0.023 0.003 0.000 0.000 0.167 0.024 0.004 0.031 0.000 0.183 0.024 0.004 0.043 0.000 0.200 0.024 0.004 0.053 0.000 0.217 0.025 0.005 0.061 0.000 0.233 0.025 0.005 0.068 0.000 0.250 0.026 0.006 0.075 0.000 0.267 0.026 0.006 0.081 0.000 0.283 0.026 0.007 0.086 0.000 0.300 0.027 0.007 0.092 0.000 0.317 0.027 0.007 0.096 0.000 0.333 0.028 0.008 0.101 0.000 0.350 0.028 0.008 0.106 0.000 0.367 0.028 0.009 0.110 0.000 0.383 0.029 0.009 0.114 0.000 0.400 0.029 0.010 0.118 0.000 0.417 0.030 0.010 0.122 0.000 0.433 0.030 0.011 0.126 0.000 0.450 0.031 0.011 0.129 0.000 0.467 0.031 0.012 0.133 0.000 0.483 0.031 0.012 0.136 0.000 0.500 0.032 0.013 0.140 0.000 0.517 0.032 0.013 0.143 0.000 0.533 0.033 0.014 0.146 0.000 0.550 0.033 0.014 0.149 0.000 0.567 0.033 0.015 0.153 0.000 0.583 0.034 0.016 0.156 0.000 0.600 0.034 0.016 0.159 0.000 0.617 0.035 0.017 0.161 0.000 0.633 0.035 0.017 0.164 0.000 0.650 0.036 0.018 0.167 0.000 0.667 0.036 0.018 0.170 0.000 0.683 0.036 0.019 0.173 0.000 0.700 0.037 0.020 0.175 0.000 0.717 0.037 0.020 0.178 0.000 0.733 0.038 0.021 0.181 0.000 0.750 0.038 0.022 0.183 0.000 0.767 0.038 0.022 0.186 0.000 0.783 0.039 0.023 0.188 0.000 0.800 0.039 0.023 0.191 0.000 0.817 0.040 0.024 0.193 0.000 0.833 0.040 0.025 0.195 0.000 0.850 0.041 0.025 0.198 0.000 0.867 0.041 0.026 0.200 0.000 0.883 0.041 0.027 0.202 0.000 0.900' 0.042 0.028 0.205 0.000 0.917 0.042 0.028 0.207 0.000 0.933 0.043 0.029 0.209 0.000 0.950 0.043 0.030 0.211 0.000 0.967 0.044 0.030 0.214 0.000 0.983 0.044 0.031 0.216 0.000 1.000 0.044 0.032 0.218 0.000 1.017 0.045 0.033 0.220 0.000 1.033 0.045 0.033 0.222 0.000 1.050 0.046 0.034 0.224 0.000 1.067 0.046 0.035 0.226 0.000 1.083 0.047 0.036 0.228 0.000 1.100 0.047 0.036 0.230 0.000 1.117 0.047 0.037 0.232 0.000 1.133 0.048 0.038 0.234 0.000 1.150 0.048 0.039 0.236 0.000 1.167 0.049 0.040 0.238 0.000 1.183 0.049 0.040 0.240 0.000 1.200 0.050 0.041 0.242 0.000 1.217 0.050 0.042 0.244 0.000 1.233 0.050 0.043 0.246 0.000 1.250 0.051 0.044 0.248 0.000 1.267 0.051 0.045 0.250 0.000 1.283 0.052 0.045 0.252 0.000 1.300 0.052 0.046 0.253 0.000 1.317 0.053 0.047 0.255 0.000 1.333 0.053 0.048 0.257 0.000 1.350 0.054 0.049 0.259 0.000 1.367 0.054 0.050 0.261 0.000 1.383 0.054 0.051 0.263 0.000 1.400 0.055 0.052 0.264 0.000 1.417 0.055 0.053 0.266 0.000 1.433 0.056 0.054 0.268 0.000 1.450 0.056 0.054 0.270 0.000 1.467 0.057 0.055 17.73 0.000 1.483 0.057 0.056 49.66 0.000 1.500 0.058 0.057 91.01 0.000 1.517 0.058 0.058 . 140.0 0.000 MITIGATED LAND USE ANALYSIS RESULTS Flow Frequency Return Periods for Predeveloped (70% of Existing) . POC #1 Return Period Flow(cfs) 2 year 0.245922 5 year 0.303985 10 year 0.342607 25 year 0.392236 50 year 0.429885 100 year 0.467961 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.172122 5 year 0.203285 10 year 0.224607 25 year 0.252336 50 year 0.273583 100 year 0.295361 Yearly Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1950 0.202 0.202 1951 0.217 0.217 1952 0.202 0.202 1953 0.157 0.157 1954 0.156 0.156 1955 0.165 0.165 1956 0.195 0.195 1957 0.177 0.177 1958 0.201 0.201 1959 0.161 0.161 1960 0.151 0.151 1961 0.194 0.194 1962 0.154 0.154 1963 0.143 0.143 1964 0.141 0.141 1965 0.172 0.172 1966 0.152 0.152 1967 0.144 0.144 1968 0.189 0.189 1969 0.188 0.188 1970 0.161 0.161 1971 0.161 0.161 1972 0.162 0.162 1973 0.219 0.219 1974 0.152 0.152 1975 0.145 0.145 1976 0.187 0.187 1977 0.147 0.147 1978 0.158 0.158 1979 0.205 0.205 1980 0.174 0.174 1981 0.190 0.190 1982 0.187 0.187 1983 0.223 0.223 1984 0.205 0.205 1985 0.143 . 0.143 1986 0.175 0.175 1987 0.210 0.210 1988 0.208 0.208 1989 0.150 0.150 1990 0.150 0.150 1991 0.357 0.357 1992 0.254 0.254 1993 0.178 0.178 1994 0.129 0.129 1995 0.136 0.136 1996 0.161 0.161 1997 0.213 0.213 1998 0.184 0.184 1999 0.163 0.163 Ranked Yearly Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.3568 0.3568 2 0.2543 0.2543 3 0.2233 0.2233 4 0.2189 0.2189 5 0.2172 0.2172 6 0.2134 0.2134 7 0.2096 0.2096 8 0.2078 0.2078 9 0.2050 0.2050 10 0.2045 0.2045 11 0.2021 0.2021 12 0.2019 0.2019 13 0.2010 0.2010 14 0.1953 0.1953 15 0.1935 0.1935 16 0.1895 0.1895 17 0.1894 0.1894 18 0.1885 0.1885 19 0.1869 0.1869 20 0.1867 0.1867 21 0.1840 0.1840 22 0.1776 0.1776 23 0.1770 0.1770 24 0.1749 0.1749 25 0.1745 0.1745 26 0.1718 0.1718 27 0.1652 0.1652 28 0.1634 0.1634 29 0.1623 0.1623 30 0.1612 0.1612 31 0.1611 0.1611 32 0.1611 0.1611 33 0.1607 0.1607 34 0.1580 0.1580 35 0.1573 0.1573 36 0.1559 0.1559 37 0.1539 0.1539 38 0.1522 0.1522 39 0.1521 0.1521 40 0.1510 0.1510 41 0.1504 0.1504 42 0.1502 0.1502 43 0.1469 0.1469 44 0.1451 0.1451 45 0.1436 0.1436 46 0.1434 0.1434 47 0.1430 0.1430 48 0.1407 0.1407 49 0.1362 0.1362 50 0.1291 0.1291 Perind and Impind 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. Fite W :Yew...Help ... ...._ D 1;7 10 10FIT 5�7 it SCENARIOS y .. _ jl F..I. Name gG'alai ' F Rredevelape 76lFeTf— -oun.t z—" Outlet 3 Downstream Connections .0. - J yet a Mrega ed Facility Type Fusp.:&dai Pond i .......... Kti .... F. ...... � Gu Scecone Facility Sono.El—whoa(iQ i0 facility Dimensions t ` Boom Length(Iry Cadet Strectur. .... ,_ _ _....._. P Rlger Heigh{� 1( as`-!i Botom WMlh 11} Rix.r I E lei Depth(11)W poser T e f�� .Left Side Slope !. Y9 �— _.Bottom Side Stop. ?} Noioa Right Side Slope Tap Side Stop.fH,M i31 menaion Diagram 1 ` _ Orifice Diameter Haight OM= - Infiletldon Number (In) (Ft) (ds) I I Measured inhNreowt Rate fo--71, t 5 X Fi 027464..........._.__.....,.... l Red ca-Factor(Mllftku) fl— j 6 l : Use Weted5urt.—Aren RS— i 1. _ - Total Yolumelnfilkatetlincre-fl} 0 Total Volume Through '26,541 Pond Volume at Piser Head �a5 M i menu fiend Increm.nt f Total Volume Through E Show Pand Table Goon Teblo ..__......_ .. _ .,. . P.M nt Infiltrated 0 3 .t Use T,d.Gets? INQ-p1 Y � r y p ` 10(29=1 1:17 PM.. Renton Sunset Stormwater Retrofit/LID Project Renton Sunset City of Renton Table 3B Tributary Area Breakdown Location: Renton Highlands, Renton, WA Sub-Basin: Harrington Avenuue NE (Westside of street); NE 10th St to NE 12th St Project Sub-Total Sub-Total Land Use site (SF) (Ac) Impervious Roadway/Parkin 10455 10455 0.24 Roofs 11326 1 11326 0.26 Driveways 11761 11761 0.27 Pond Sidewalk 4791 4791 0.11 Pervious Till Landsca e 33106 33106 0.76 Outwash Landscape Saturated Landscape Green Roof Pervious Pavement Sub-total 71439 1.64 Total 71439 1.64 Western Washington Hydrology Model PROJECT REPORT Project Name: MH-W-1011 Site Address: Renton Highlands City Renton Report Date 10/29/2012 Gage Seatac Data Start 1948/10/01 Data End 1998/09/30 Precip Scale: 1.00 WWHM3 Version: PREDEVELOPED LAND USE Name Basin 1 Bypass: No GroundWater: No Pervious Land Use Acres A B, Lawn, Mod .76 Impervious Land Use Acres ROADS FLAT 0.35 ROOF TOPS FLAT 0.26 DRIVEWAYS FLAT 0.27 Element Flows To: Surface Interflow Groundwater Name Basin 1 Bypass: No GroundWater: No Pervious Land Use Acres A B, Lawn, Mod .76 Impervious Land Use Acres ROADS FLAT 0.35 ROOF TOPS FLAT 0.26 DRIVEWAYS FLAT 0.27 Element Flows To: Surface Interflow Groundwater Swalel, Swalel, Name Swalel Bottom Length: 110ft. Bottom Width: 5ft. Depth : 1.5ft. Volume at riser head : 0.0364ft. Infiltration On Infiltration rate : 0 Infiltration saftey factor 1 Wetted surface area On Side slope 1: 3 To 1 Side slope 2: 3 To 1 Side slope 3: 3 To 1 Side slope 4: 3 To 1 Discharge Structure Riser Height: 1.45 ft. Riser Diameter: 10000 in. Orifice 1 Diameter: 3 in. Elevation: 0.15 ft. Element Flows To: Outlet 1 Outlet 2 Pond Hydraulic Table Stage(ft) Area(acr) Volume(acr-ft) Dschrg(cfs) Infilt(cfs) 0.000 0.013 0.000 0.000 0.000 0.017 0.013 0.000 0.000 0.000 0.033 0.013 0.000 0.000 0.000 0.050 0.013 0.001 0.000 0.000 0.067 0.014 0.001 0.000 0.000 0.083 0.014 0.001 0.000 0.000 0.100 0.014 0.001 0.000 0.000 0.117 0.014 0.002 0.000 0.000 0.133 0.015 0.002 0.000 0.000 0.150 0.015 0.002 0.000 0.000 0.167 0.015 0.002 0.031 0.000 0.183 0.016 0.003 0.043 0.000 0.200 0.016 0.003 0.053 0.000 0.217 0.016 0.003 0.061 0.000 0.233 0.016 0.003 0.068 0.000 0.250 0.017 0.004 0.075 0.000 0.267 0.017 0.004 0.081 0.000 0.283 0.017 0.004 0.086 0.000 0.300 0.017 0.005 0.092 0.000 0.317 0.018 0.005 0.096 0.000 0.333 0.018 0.005 0.101 0.000 0.350 0.018 0.005 0.106 0.000 0.367 0.019 0.006 0.110 0.000 0.383 0.019 0.006 0.114 0.000 0.400 0.019 0.006 0.118 0.000 0.417 0.019 0.007 0.122 0.000 0.433 0.020 0.007 0.126 0.000 0.450 0.020 0.007 0.129 0.000 0.467 0.020 0.008 0.133 0.000 0.483 0.020 0.008 0.136 0.000 0.500 0.021 0.008 0.140 0.000 0.517 0.021 0.009 0.143 0.000 0.533 0.021 0.009 0.146 0.000 0.550 0.022 0.009 0.149 0.000 0.567 0.022 0.010 0.153 0.000 0.583 0.022 0.010 0.156 0.000 0.600 0.022 0.010 0.159 0.000 0.617 0.023 0.011 0.161 0.000 0.633 0.023 0.011 0.164 0.000 0.650 0.023 0.012 0.167 0.000 ° 0.667 0.024 0.012 0.170 0.000 0.683 0.024 0.012 0.173 0.000 0.700 0.024 0.013 0.175 0.000 0.717 0.024 0.013 0.178 0.000 0.733 0.025 0.014 0.181 0.000 0.750 0.025 0.014 0.183 0.000 0.767 0.025 0.014 0.186 0.000 0.783 0.026 0.015 0.188 0.000 0.800 0.026 0.015 0.191 0.000 0.817 0.026 0.016 0.193 0.000 0.833 0.026 0.016 0.195 0.000 0.850 0.027 0.017 0.198 0.000 0.867 0.027 0.017 0.200 0.000 0.883 0.027 0.018 0.202 0.000 0.900 0.028 0.018 0.205 0.000 0.917 0.028 0.018 0.207 0.000 0.933 0.028 0.019 0.209 0.000 0.950 0.028 0.019 0.211 0.000 0.967 0.029 0.020 0.214 0.000 0.983 0.029 0.020 0.216 0.000 1.000 0.029 0.021 0.218 0.000 1.017 0.030 0.021 0.220 0.000 1.033 0.030 0.022 0.222 0.000 ° 1.050 0.030 0.022 0.224 0.000 1.067 0.030 0.023 0.226 0.000 1.083 0.031 0.023 0.228 0.000 1.100 0.031 0.024 0.230 0.000 1.117 0.031 0.024 0.232 0.000 1.133 0.032 0.025 0.234 0.000 1.150 0.032 0.025 0.236 0.000 1.167 0.032 0.026 0.238 0.000 1.183 0.033 0.026 0.240 0.000 1.200 0.033 0.027 0.242 0.000 1.217 0.033 0.028 0.244 0.000 1.233 0.033 0.028 0.246 0.000 1.250 0.034 0.029 0.248 0.000 1.267 0.034 0.029 0.250 0.000 1.283 0.034 0.030 0.252 0.000 1.300 0.035 0.030 0.253 0.000 1.317 0.035 0.031 0.255 0.000 1.333 0.035 0.032 0.257 0.000 1.350 0.036 0.032 0.259 0.000 1.367 0.036 0.033 0.261 0.000 1.383 0.036 0.033 0.263 0.000 1.400 0.036 0.034 0.264 0.000 1.417 0.037 0.035 0.266 0.000 1.433 0.037 0.035 0.268 0.000 1.450 0.037 0.036 0.270 0.000 1.467 0.038 0.036 17.73 0.000 1.483 0.038 0.037 49.66 0.000 1.500 0.038 0.038 91.01 0.000 1.517 0.039 0.038 140.0 0.000 MITIGATED LAND USE ANALYSIS RESULTS Flow Frequency Return Periods for Predeveloped . POC #1 Return Period Flow(cfs) 2 year 0.223141 5 year 0.275762 10 year 0.310862 25 year 0.355853 50 year 0.389878 100 year 0.42446 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.172225 5 year 0.202904 10 year 0.223453 25 year 0.249766 50 year 0.269664 100 year 0.289849 Yearly Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1950 0.158 0.200 1951 0.286 0.228 1952 0.172 0.198 1953 0.137 0.153 1954 0.124 0.155 1955 0.149 0.169 1956 0.157 0.187 1957 0.152 0.179 1958 0.171 0.198 1959 0.156 0.163 1960 0.120 0.147 1961 0.149 0.189 1962 0.143 0.154 1963 0.135 0.144 1964 0.130 0.146 1965 0.154 0.176 1966 0.136 0.152 1967 0.135 0.137 1968 0.203 0.193 1969 0.229 0.195 1970 0.123 0.156 1971 0.135 0.164 1972 0.131 0.159 1973 0.213 0.218 1974 0.123 0.153 1975 0.135 0.145 1976 0.177 0.183 1977 0.122 0.143 1978 0.157 0.156 1979 0.204 0.202 1980 0.202 0.186 1981 0.166 0.191 1982 0.185 0.187 1983 0.252 0.228 1984 0.187 0.203 1985 0.141 0.145 1986 0.134 0.171 1987 0.164 0.198 1988 0.233 0.209 1989 0.112 0.146 1990 0.141 0.157 1991 0.264 0.345 1992 0.241 0.255 1993 0.139 0.177 1994 0.096 0.127 1995 0.115 0.136 1996 0.144 0.162 1997 0.189 0.204 1998 0.176 0.182 1999 0.176 0.170 Ranked Yearly Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.2861 0.3450 2 0.2636 0.2554 3 0.2520 0.2284 4 0.2413 0.2277 5 0.2334 0.2176 6 0.2292 0.2090 7 0.2126 0.2039 8 0.2041 0.2032 9 0.2025 0.2020 10 0.2017 0.2003 11 0.1885 0.1981 12 0.1868 0.1980 13 0.1850 0.1975 14 0.1769 0.1948 15 0.1761 0.1931 16 0.1759 0.1911 17 0.1718 0.1894 18 0.1714 0.1870 19 0.1660 0.1870 20 0.1635 0.1859 21 0.1576 0.1834 22 0.1575 0.1821 23 0.1571 0.1792 24 0.1559 0.1774 25 0.1540 0.1765 26 0.1515 0.1710 27 0.1486 0.1704 28 0.1485 0.1693 29 0.1436 0.1640 30 0.1431 0.1630 31 0.1410 0.1617 32 0.1405 0.1590 33 0.1392 0.1571 34 0.1375 0.1563 35 0.1363 0.1561 36 0.1348 0.1547 37 0.1347 0.1537 38 0.1346 0.1533 39 0.1346 0.1529 40 0.1336 0.1518 41 0.1313 0.1471 42 0.1296 0.1458 43 0.1240 0.1456 44 0.1230 0.1449 45 0.1229 0.1446 46 0.1218 0.1443 47 0.1197 0.1428 48 0.1154 0.1375 49 0.1124 0.1359 50 0.0964 0.1271 Perind and xmpind 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. .............. Fes. F.fi{..Y, wp , D1061 0 I ' SCENARIOS '"`•::". .Facility Name r P*adeveiope poHei"P—' 0.11.1_3. _.._. Dawnsf nm CannP.fti ( Q Q Faaliy Type �t'rape oitlai Pantl ......__ Fun Scennne vV + A�'.nd--j .quick Pond Fl FYFNTC "��" _ acrr Faaliy Sotto Elele vma (it) 1 Faality D.undone Son—L ngth(try Outlet Strertere f3a0om width(a) °" Pocer Heigh{try ,1T 45-!4 E1>�Wti�Depth lh) )'rd Ricer 1 QO 00'8'I m depth of Balm l fi Ifcot of frca-bo and abtrve tap�'rett-_� ti.ftm a ope Right S.de 5lape Top Side Slope Q{N: Factiry Dnnetmmn Dmgrom ----------- prince Diameter Heigh OtAmc Mfilbmion Number (In) (Fq (dc) Measured tr hihanai Rate 0.27464 i P.&u fion Fector(intilr%e t r) ri --�j 2 U:eevenedSurtnalArea y(T; � 3 FO Q 6 3 Total Yolume Intiltratsd(acre-h) 0 Tote)Volume Through t14.767 Fond Volume of Riser Head 036 }}Msnm Eltaments Fond Increment010 ..`� r Total Volume Through 1.1477 Percem irnittreted Q Shaw Pand Table €Coen Table^:-I Li Use Troe GaN? ''.Np .. . a ; � I c 3 mv Ao.. �. � ._... 10f2W201 102 NO Renton Sunset Stormwater Retrofit/LID Project Renton Sunset City of Renton Table 4 Tributary Area Breakdown Location: Renton Highlands, Renton, WA Sub-Basin: Harrington Avenuue NE (Bothsides of street); NE 9th St to SR 900 Project Sub-Total Sub-Total Land Use site (SF) (Ac) Impervious Roadway/Parking Roadway/Parking 42368 42368 0.97 Roofs Driveways Pond Sidewalk 8162 8162 0.19 Pervious Till Landsca e Outwash Landscape Saturated Landscape Green Roof Pervious Pavement Sub-total 50530 1.16 Total 50530 1.16 Western Washington Hydrology Model PROJECT REPORT Project Name: SH-N-1014 Site Address: Renton Highlands City Renton Report Date 10/29/2012 Gage Seatac Data Start 1948/10/01 Data End 1998/09/30 Precip Scale: 1.00 WWHM3 Version: PREDEVELOPED LAND USE Name Basin 1 Bypass: No GroundWater: No Pervious Land Use Acres Impervious Land Use Acres ROADS FLAT 0.62 DRIVEWAYS FLAT 0.33 SIDEWALKS FLAT 0.21 Element Flows To: Surface Interflow Groundwater Name Basin 1 Bypass: No GroundWater: No Pervious Land Use Acres Impervious Land Use Acres ROADS FLAT 0.62 DRIVEWAYS FLAT 0.33 SIDEWALKS FLAT 0.21 Element Flows To: Surface Interflow Groundwater Swalel, Swalel, Name Swalel Bottom Length: 2OOft. Bottom Width: 5ft. Depth : 1.5ft. Volume at riser head : 0.0649ft. Infiltration On Infiltration rate : 1.2 Infiltration saftey factor 1 Wetted surface area On Side slope 1: 3 To 1 • Side slope 2: 3 To 1 Side slope 3: 3 To 1 Side slope 4: 3 To 1 Discharge Structure Riser Height: 1.45 ft. Riser Diameter: 10000 in. Orifice 1 Diameter: 2.7 in. Elevation: 0.15 ft. Element Flows To: Outlet 1 Outlet 2 Pond Hydraulic Table Stage(ft) Area(acr) Volume(acr-ft) Dschrg(cfs) Infilt(cfs) 0.000 0.023 0.000 0.000 0.000 0.017 0.023 0.000 0.000 0.028 0.033 0.024 0.001 0.000 0.029 0.050 0.024 0.001 0.000 0.030 0.067 0.025 0.002 0.000 0.030 0.083 0.025 0.002 0.000 0.031 0.100 0.026 0.002 0.000 0.031 • 0.117 0.026 0.003 0.000 0.032 0.133 0.027 0.003 0.000 0.033 0.150 0.027 0.004 0.000 0.033 0.167 0.028 0.004 0.025 0.034 0.183 0.028 0.005 0.035 0.034 0.200 0.029 0.005 0.043 0.035 0.217 0.029 0.006 0.049 0.036 0.233 0.030 0.006 0.055 0.036 0.250 0.030 0.007 0.061 0.037 0.267 0.031 0.007 0.065 0.037 0.283 0.031 0.008 0.070 0.038 0.300 0.032 0.008 0.074 0.039 0.317 0.032 0.009 0.078 0.039 0.333 0.032 0.009 0.082 0.040 0.350 0.033 0.010 0.086 0.041 0.367 0.033 0.010 0.089 0.041 0.383 0.034 0.011 0.092 0.042 0.400 0.034 0.011 0.096 0.042 • 0.417 0.035 0.012 0.099 0.043 0.433 0.035 0.013 0.102 0.044 0.450 0.036 0.013 0.105 0.044 0.467 0.036 0.014 0.108 0.045 0.483 0.037 0.014 0.111 0.045 0.500 0.037 0.015 0.113 0.046 0.517 0.038 0.016 0.116 0.047 0.533 0.038 0.016 0.119 0.047 0.550 0.039 0.017 0.121 0.048 0.567 0.039 0.018 0.124 0.049 0.583 0.040 0.018 0.126 0.049 0.600 0.040 0.019 0.128 0.050 0.617 0.041 0.020 0.131 0.050 0.633 0.041 0.020 0.133 0.051 0.650 0.042 0.021 0.135 0.052 0.667 0.042 0.022 0.138 0.052 0.683 0.043 0.022 0.140 0.053 0.700 0.043 0.023 0.142 0.054 0.717 0.044 0.024 0.144 0.054 0.733 0.044 0.025 0.146 0.055 0.750 0.045 0.025 0.148 0.055 0.767 0.045 0.026 0.150 0.056 0.783 0.046 0.027 0.152 0.057 0.800 0.046 0.028 0.154 0.057 0.817 0.047 0.028 0.156 0.058 0.833 0.047 0.029 0.158 0.059 0.850 0.048 0.030 0.160 0.059 0.867 0.048 0.031 0.162 0.060 0.883 0.049 0.031 0.164 0.060 0.900 0.049 0.032 0.166 0.061 0.917 0.050 0.033 0.168 0.062 0.933 0.050 0.034 0.169 0.062 0.950 0.051 0.035 0.171 0.063 0.967 0.051 0.036 0.173 0.064 0.983 0.052 0.036 0.175 0.064 1.000 0.052 0.037 0.177 0.065 1.017 0.053 0.038 0.178 0.065 1.033 0.053 0.039 0.180 0.066 1.050 0.054 0.040 0.182 0.067 1.067 0.054 0.041 0.183 0.067 1.083 0.055 0.042 0.185 0.068 1.100 0.055 0.043 0.187 0.069 1.117 0.056 0.044 0.188 0.069 1.133 0.056 0.045 0.190 0.070 1.150 0.057 0.045 0.191 0.071 1.167 0.057 0.046 0.193 0.071 1.183 0.058 0.047 0.195 0.072 1.200 0.058 0.048 0.196 0.073 1.217 0.059 0.049 0.198 0.073 1.233 0.059 0.050 0.199 0.074 1.250 0.060 0.051 0.201 0.074 1.267 0.060 0.052 0.202 0.075 1.283 0.061 0.053 0.204 0.076 1.300 0.061 0.054 0.205 0.076 1.317 0.062 0.055 0.207 0.077 1.333 0.062 0.056 0.208 0.078 1.350 0.063 0.057 0.210 0.078 1.367 0.063 0.058 0.211 0.079 1.383 0.064 0.060 0.213 0.080 1.400 0.064 0.061 0.214 0.080 1.417 0.065 0.062 0.215 0.081 1.433 0.065 0.063 0.217 0.082 1.450 0.066 0.064 0.218 0.082 1.467 0.066 0.065 17.68 0.083 1.483 0.067 0.066 49.61 0.084 1.500 0.067 0.067 90.96 0.084 1.517 0.068 0.068 139.9 0.085 MITIGATED LAND USE ANALYSIS RESULTS Flow Frequency Return Periods for Predeveloped POC #1 Return Period Flow(cfs) 2 year 0.289818 5 year 0.352258 10 year 0.392704 25 year 0.443151 50 year 0.480431 100 year 0.517607 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.041418 5 year 0.080758 10 year 0.120504 25 year 0.192251 50 year 0.265931 100 year 0.361607 Yearly Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1950 0.036 0.036 1951 0.034 0.034 1952 0.108 0.108 1953 0.028 0.028 1954 0.029 0.029 1955 0.028 0.028 1956 0.087 0.087 1957 0.036 0.036 1958 0.038 0.038 1959 0.034 0.034 1960 0.031 0.031 1961 0.096 0.096 1962 0.030 0.030 1963 0.026 0.026 1964 0.026 0.026 1965 0.029 0.029 1966 0.032 0.032 1967 0.028 0.028 1968 0.039 0.039 1969 0.030 0.030 1970 0.034 0.034 1971 0.032 0.032 1972 0.030 0.030 1973 0.098 0.098 1974 0.031 0.031 1975 0.026 0.026 1976 0.093 0.093 1977 0.030 0.030 1978 0.029 0.029 1979 0.037 0.037 1980 0.028 0.028 1981 0.037 0.037 1982 0.032 0.032 1983 0.232 0.232 1984 0.037 0.037 1985 0.030 0.030 1986 0.033 0.033 1987 0.203 0.203 1988 0.189 0.189 1989 0.028 0.028 1990 0.023 0.023 1991 0.318 0.318 1992 0.277 0.277 1993 0.032 0.032 1994 0.029 0.029 1995 0.023 0.023 1996 0.033 0.033 1997 0.204 0.204 1998 0.126 0.126 1999 0.030 0.030 Ranked Yearly Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.3182 0.3182 2 0.2770 0.2770 3 0.2321 0.2321 4 0.2036 0.2036 ' 5 0.2032 0.2032 6 0.1892 0.1892 7 0.1261 0.1261 8 0.1083 0.1083 9 0.0978 0.0978 10 0.0959 0.0959 11 0.0926 0.0926 12 0.0874 0.0874 13 0.0386 0.0386 14 0.0384 0.0384 15 0.0370 0.0370 16 0.0367 0.0367 17 0.0365 0.0365 18 0.0361 0.0361 19 0.0357 0.0357 20 0.0345 0.0345 21 0.0340 0.0340 22 0.0337 0.0337 23 0.0334 0.0334 24 0.0326 0.0326 25 0.0324 0.0324 26 0.0324 0.0324 27 0.0321 0.0321 28 0.0318 0.0318 29 0.0315 0.0315 30 0.0305 0.0305 31 0.0304 0.0304 32 0.0304 0.0304 33 0.0298 0.0298 34 0.0297 0.0297 35 0.0297 0.0297 36 0.0295 0.0295 37 0.0294 0.0294 38 0.0290 0.0290 39 0.0286 0.0286 40 0.0285 0.0285 41 0.0283 0.0283 42 0.0280 0.0280 43 0.0278 0.0278 44 0.0276 0.0276 45 0.0276 0.0276 46 0.0259 0.0259 47 0.0257 0.0257 48 0.0256 0.0256 49 0.0231 0.0231 50 0.0226 0.0226 Per1nd and Imp1nd 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 impliea, 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. --- __ -Fik Emt ymv Rdp : dam.. . , SCENARIOS .T Facility Name nwalal ...... _...... j' Dat["t T-"""Ouaet 7 _ Outlet 7 FredeVelPPe Downstream Connection. E-._ _._._._,_.,Q _. Q ___ .._... D _ 'F.Mrtiga'.ed _..... Facility Type (Trapezoidal Pond 3. ........... ....... �j dun 5cenaiia r ?w�o.,,,.�nd�f quick Pond 1 �r Facility Bottom Etevabon(Iq g ]. —���•--� Facility Dimensions Boll—LengM(tq 3 RiOodet Sl ` _.. - BPlIPrn WMMiX) ser Heightift)h{a) 7�-;-Be,"Depth On ! . Riser Flo a-.H llrr'it Len Side Slope;H(V) Poser Type F{(y• ��-� rq Bolt—S de Slope Right Side Slope 3 Top Side Slope(H!V) '— Facility Dimeltsion Diagram r --4 a ....... Orifice DiameterHeight OUair Infiltration 'ES Number (In) (Ft) (M) j. _ ..__...�- .......... ._ ._._... Measumdl fiWanan Pale 12i-:3 1 2j 7 -+�pt5 -?-� 0.22246 ReducEon Fador(inhlRado') ]�—'8'! 2 n j0'`•'3 0 . .� Use Weaed Surface A— Total Volume lnfilrated(acm-fl) 'Q5.68 I Total Volume Through 95.297 Pond Volume al Riser Head 365 `Move lemenh Pontl lncremerit Total Volume Through ':5032 Coen Tebm .. PercentimAroted 7A02 Show,Pond Table j au p ... _... .. rw 1 r � 3 L 10/29/201 1:22 PM Renton Sunset Stormwater Retrofit/LID Project Renton Sunset City of Renton Table 5 Tributary Area Breakdown Location: Renton Highlands, Renton, WA Sub-Basin: Harrington Avenuue NE (Eastside); NE 7th St to NE 9th St Project Sub-Total Sub-Total Land Use site (SF) (Ac) Impervious Roadway/Parking 14801 14801 0.34 Roofs 29621 1 1 29621 0.68 Driveways 28314 28314 0.65 Pond Sidewalk 5009 5009 0.12 Pervious Till Landscape Outwash Landscape 37026 37026 0.85 Saturated Landscape Green Roof Pervious Pavement Sub-total 114771 2.63 Total 114771 2.63 Western Washington Hydrology Model PROJECT REPORT Project Name: SouthHS_E_vl Site Address: City Report Date 10/23/2012 Gage Seatac Data Start 1948/10/01 Data End 1998/09/30 Precip Scale: 1 .00 WWHM3 Version: PREDEVELOPED LAND USE Name 3asin 1 Bypass: No GroundWater: No Pervious Land Use Acres A B, Lawn, Flat .85 Impervious Land Use Acres ROADS FLAT 1.78 Element Flows To: Surface Interflow Groundwater Name 3asin 1 Bypass: No GroundWater: No Pervious Land Use Acres A B, Lawn, Flat .85 Impervious Land Use Acres ROADS FLAT 1.78 Element Flows To: Surface Interflow Groundwater Trapezoidal Pond 2, Trapezoidal Pond 2, Name Trapezoidal Pond 2 Bottom Length: 280ft. Bottom Width: 6ft. Depth : 1.95ft. Volume at riser head : 0.0983ft. Infiltration On Infiltration rate : 1.2 Infiltration saftey factor : 1 Side sloped: 3 To 1 Side slope 2: 3 To 1 Side slope 3: 3 To 1 Side slope 4: 3 To 1 Discharge Structure Riser Height: 1.45 ft. Riser Diameter: 18 in. Orifice 1 Diameter: 3 in. Elevation: 0.15 ft. Element Flows To: Outlet 1 Outlet 2 Pond Hydraulic Table Stage(ft) Area(acr) Volume(acr-ft) Dschrg(cfs) Infilt(cfs) 0.000 0.039 0.000 0.000 0.000 0.022 0.039 0.001 0.000 0.047 0.043 0.040 0.002 0.000 0.047 0.065 0.041 0.003 0.000 0.047 0.087 0.042 0.003 0.000 0.047 0.108 0.043 0.004 0.000 0.047 0.130 0.044 0.005 0.000 0.047 0.152 0.045 0.006 0.010 0.047 0.173 0.045 0.007 0.036 0.047 0.195 0.046 0.008 0.050 0.047 0.217 0.047 0.009 0.061 0.047 0.238 0.048 0.010 0.070 0.047 0.260 0.049 0.011 0.078 0.047 0.282 0.050 0.012 0.086 0.047 0.303 0.051 0.014 0.093 0.047 0.325 0.051 0.015 0.099 0.047 0.347 0.052 0.016 0.105 0.047 0.368 0.053 0.017 0.110 0.047 0.390 0.054 0.018 0.116 0.047 0.412 0.055 0.019 0.121 0.047 0.433 0.056 0.020 0.126 0.047 0.455 0.057 0.022 0.131 0.047 0.477 0.058 0.023 0.135 0.047 0.498 0.058 0.024 0.140 0.047 0.520 0.059 0.025 0.144 0.047 0.542 0.060 0.027 0.148 0.047 0.563 0.061 0.028 0.152 0.047 0.585 0.062 0.029 0.156 0.047 0.607 0.063 0.031 0.160 0.047 0.628 0.064 0.032 0.163 0.047 0.650 0.065 0.033 0.167 0.047 0.672 0.065 0.035 0.171 0.047 0.693 0.066 0.036 0.174 0.047 0.715 0.067 0.038 0.178 0.047 0.737 0.068 0.039 0.181 0.047 0.758 0.069 0.041 0.184 0.047 0.780 0.070 0.042 0.188 0.047 0.802 0.071 0.044 0.191 0.047 0.823 0.072 0.045 0.194 0.047 0.845 0.072 0.047 0.197 0.047 0.867 0.073 0.048 0.200 0.047 0.888 0.074 0.050 0.203 0.047 0.910 0.075 0.052 0.206 0.047 0.932 0.076 0.053 0.209 0.047 0.953 0.077 0.055 0.212 0.047 0.975 0.078 0.057 0.215 0.047 0.997 0.079 0.058 0.217 0.047 1.018 0.080 0.060 0.220 0.047 1.040 0.080 0.062 0.223 0.047 1.062 0.081 0.063 0.226 0.047 1.083 0.082 0.065 0.228 0.047 1.105 0.083 0.067 0.231 0.047 1.127 0.084 0.069 0.234 0.047 1.148 0.085 0.071 0.236 0.047 1.170 0.086 0.073 0.239 0.047 1.192 0.087 0.074 0.241 0.047 1.213 0.088 0.076 0.244 0.047 1.235 0.088 0.078 0.246 0.047 1.257 0.089 0.080 0.249 0.047 1.278 0.090 0.082 0.251 0.047 1.300 0.091 0.084 0.253 0.047 1.322 0.092 0.086 0.256 0.047 1.343 0.093 0.088 0.258 0.047 1.365 0.094 0.090 0.261 0.047 1.387 0.095 0.092 0.263 0.047 1.408 0.096 0.094 0.265 0.047 1.430 0.097 0.096 0.267 0.047 1.452 0.097 0.098 0.271 0.047 1.473 0.098 0.100 0.324 0.047 1.495 0.099 0.103 0.414 0.047 1.517 0.100 0.105 0.528 0.047 1.538 0.101 0.107 0.662 0.047 1.560 0.102 0.109 0.814 0.047 1.582 0.103 0.111 0.981 0.047 1.603 0.104 0.114 1.162 0.047 1.625 0.105 0.116 1.357 0.047 1.647 0.106 0.118 1.563 0.047 1.668 0.107 0.120 1.782 0.047 1.690 0.108 0.123 2.011 0.047 1.712 0.108 0.125 2.251 0.047 1.733 0.109 0.127 2.501 0.047 1.755 0.110 0.130 2.760 0.047 1.777 0.111 0.132 3.029 0.047 1.798 0.112 0.135 3.307 0.047 1.820 0.113 0.137 3.593 0.047 1.842 0.114 0.140 3.888 0.047 1.863 0.115 0.142 4.191 0.047 1.885 0.116 0.145 4.503 0.047 1.907 0.117 0.147 4.822 0.047 1.928 0.118 0.150 5.148 0.047 1.950 0.119 0.152 5.482 0.047 MITIGATED LAND USE ANALYSIS RESULTS Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.448465 5 year 0.54844 10 year 0.613345 25 year 0.694602 50 year 0.754884 100 year 0.815139 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.204868 5 year 0.260533 10 year 0.3017 25 year 0.358719 50 year 0.404949 100 year 0.454513 Yearly Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1950 0.455 0.237 1951 0.732 0.228 1952 0.466 0.247 1953 0.397 0.181 1954 0.357 0.188 1955 0.426 0.185 1956 0.454 0.251 1957 0.438 0.210 1958 0.495 0.244 1959 0.450 0.200 1960 0.346 0.180 1961 0.429 0.242 1962 0.393 0.182 1963 0.389 0.168 1964 0.371 0.160 1965 0.441 0.197 1966 0.393 0.171 1967 0.389 0.175 1968 0.585 0.233 1969 0.662 0.209 1970 0.354 0.199 1971 0.389 0.192 1972 0.379 0.192 1973 0.567 0.261 1974 0.355 0.188 1975 0.389 0.166 1976 0.511 0.239 1977 0.352 0.177 1978 0.455 0.175 1979 0.590 0.241 1980 0.583 0.191 1981 0.479 0.228 1982 0.535 0.215 1983 0.728 0.262 1984 0.540 0.239 1985 0.405 0.168 1986 0.386 0.210 1987 0.469 0.269 1988 0.674 0.259 1989 0.325 0.179 1990 0.407 0.155 1991 0.742 0.651 1992 0.689 0.504 1993 0.402 0.208 1994 0.279 0.147 1995 0.333 0.153 1996 0.415 0.192 1997 0.510 0.267 1998 0.484 0.255 1999 0.508 0.186 Ranked Yearly Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.7421 0.6511 2 0.7324 0.5040 3 0.7279 0.2692 4 0.6886 0.2665 5 0.6742 0.2617 6 0.6620 0.2610 7 0.5897 0.2593 8 0.5852 0.2547 9 0.5827 0.2506 10 0.5670 0.2469 11 0.5398 0.2444 12 0.5345 0.2417 13 0.5112 0.2409 14 0.5101 0.2391 15 0.5080 0.2389 16 0.4951 0.2373 17 0.4843 0.2331 18 0.4794 0.2283 19 0.4691 0.2282 20 0.4657 0.2151 21 0.4550 0.2104 22 0.4548 0.2104 23 0.4537 0.2090 24 0.4505 0.2085 25 0.4408 0.2004 26 0.4378 0.1992 27 0.4291 0.1969 28 0.4256 0.1924 29 0.4150 0.1923 30 0.4074 0.1920 31 0.4048 0.1914 32 0.4022 0.1883 33 0.3972 0.1877 34 0.3929 0.1862 35 0.3928 0.1846 36 0.3892 0.1816 37 0.3890 0.1807 38 0.3889 0.1803 39 0.3889 0.1791 40 0.3861 0.1774 41 0.3794 0.1747 42 0.3710 0.1747 • 43 0.3575 0.1714 44 0.3548 0.1685 45 0.3542 0.1678 46 0.3518 0.1663 47 0.3459 0.1605 48 0.3333 0.1546 49 0.3246 0.1527 50 0.2785 0.1470 POC #1 The Facility PASSED The Facility PASSED. Flow(CFS) Predev Dev Percentage Pass/Fail 0.2242 1162 66 5 Pass 0.2296 1080 61 5 Pass 0.2350 1002 57 5 Pass 0.2403 911 56 6 Pass 0.2457 851 53 6 Pass 0.2510 778 50 6 Pass • 0.2564 725 49 6 Pass 0.2618 680 47 6 Pass 0.2671 630 45 7 Pass 0.2725 583 41 7 Pass 0.2778 555 40 7 Pass 0.2832 503 39 7 Pass 0.2886 466 35 7 Pass 0.2939 431 30 6 Pass 0.2993 410 27 6 Pass 0.3046 390 25 6 Pass 0.3100 359 25 6 Pass 0.3154 326 25 7 Pass 0.3207 307 22 7 Pass 0.3261 286 21 7 Pass 0.3314 259 21 8 Pass 0.3368 238 21 8 Pass 0.3422 217 20 9 Pass 0.3475 205 20 9 Pass 0.3529 192 17 8 Pass 0.3582 183 16 8 Pass 0.3636 174 14 8 Pass 0.3690 164 14 8 Pass 0.3743 149 12 8 Pass 0.3797 142 12 8 Pass 0.3850 129 11 8 Pass 0.3904 120 11 9 Pass 0.3958 112 11 9 Pass 0.4011 106 11 10 Pass 0.4065 97 11 11 Pass 0.4118 91 10 10 Pass 0.4172 87 10 11 Pass 0.4226 82 8 9 Pass 0.4279 78 7 8 Pass 0.4333 72 7 9 Pass 0.4386 68 7 10 Pass 0.4440 64 7 10 Pass 0.4494 58 6 10 Pass 0.4547 54 6 11 Pass 0.4601 50 6 12 Pass 0.4654 49 6 12 Pass 0.4708 46 6 13 Pass 0.4762 43 5 11 Pass 0.4815 40 5 12 Pass 0.4869 37 5 13 Pass 0.4922 35 5 14 Pass 0.4976 32 5 15 Pass 0.5030 31 4 12 Pass 0.5083 30 4 13 Pass 0.5137 27 4 14 Pass 0.5190 26 4 15 Pass 0.5244 26 4 15 Pass 0.5298 25 4 16 Pass 0.5351 24 4 16 Pass 0.5405 21 4 19 Pass 0.5458 20 4 20 Pass 0.5512 20 3 15 Pass 0.5566 19 3 15 Pass 0.5619 18 3 16 Pass 0.5673 18 2 11 Pass 0.5726 16 2 12 Pass 0.5780 16 2 12 Pass 0.5834 14 2 14 Pass 0.5887 12 2 16 Pass 0.5941 11 2 18 Pass 0.5994 11 2 18 Pass 0.6048 11 1 9 Pass 0.6102 11 1 9 Pass 0.6155 11 1 9 Pass 0.6209 11 1 9 Pass 0.6262 10 1 10 Pass 0.6316 10 1 10 Pass 0.6370 10 1 10 Pass 0.6423 10 1 10 Pass 0.6477 9 0 0 Pass 0.6530 9 0 0 Pass 0.6584 9 0 0 Pass 0.6638 7 0 0 Pass 0.6691 6 0 0 Pass 0.6745 6 0 0 Pass 0.6798 4 0 0 Pass 0.6852 4 0 0 Pass 0.6906 3 0 0 Pass 0.6959 3 0 0 Pass 0.7013 3 0 0 Pass 0.7066 3 0 0 Pass 0.7120 3 0 0 Pass 0.7174 3 0 0 Pass 0.7227 3 0 0 Pass 0.7281 2 0 0 Pass 0.7334 1 0 0 Pass 0.7388 1 0 0 Pass 0.7442 0 0 0 Pass 0.7495 0 0 0 Pass 0.7549 0 0 0 Pass Water Quality BMP Flow and Volume for POC 1. On-line facility volume: 0.2135 acre-feet On-line facility target flow: 0.2515 cfs. Adjusted for 15 min: 0.2842 cfs. Off-line facility target flow: 0.1448 cfs. Adjusted for 15 min: 0.1636 cfs. Perind and Impind 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 Wash}ngton State Department of Ecology has been advised of the possibility of such damages. aM4mC Nnn � x > E• hM.'Ytif+Wlbta PM-wiui pq E � � ' t da�i P�5tRMMbf SBA i�a NsvH&� i Sai #faW S',ut Step p .. yk-1 t aNc�Yq.•3i:R L.�e.:: I aaaaa�. E dMY iYm m3 4hdrce L.nPM�M>«x��l!� tYaHW {g"- IM(b < Nwafr+i (IM iiPi fCaa) �.. augxgw,Pmd�"r�snx� _ Z �.�rweew'§rm�el�aPcswWt `wl_„ 3 v � _— �Miax4tb+dq»ras} 13tiit� ' �wtty t�sdsc 15 PI�bE �t+'mww r�.ax MY r 3 wd.wr:.w r:w..,yz«ayuer«�y YN'Q Wd t'w'�""e i A �n tk+n+a 4 �4; PJ+ar�ktll/?nbte W��a.."u r 101,1 012 Us PM 10/31/2012 City Of Renton-Sunset LID Pre-Desiga Harrington Avenue NE Peak Flow Rate Reduction Harrington NE16th Street to NE 12th Steet.East Side Peak Flow Rates(cfs) Events Existing Proposed %Reduction 2-yr 0.3405 0.035 89.7% 5-yr 0.4298 0.0568 86.8% 10-yr 0.4917 0.0759 84.6% 25-yr 0.5732 0.1065 81.4% 50-yr 0.6364 0.1347 78.8% 100-yr 0.7018 0.1683 76.0% Harrington NE16th Street to NE 12th Steet.West Side Peak Flow Rates(cfs) Events Existing Proposed %Reduction 2-yr 0.1424 0.0194 86.4% 5-yr 0.1731 0.0377 78.2% 10-yr 0.1929 0.0561 70.9% 25-yr 0.2177 0.0893 59.0% 50-yr 0.2361 0.1233 47.8% 100-yr 0.2543 0.1674 34.2% Harrington NE12th Street to NE 10th Steet.East Side Peak Flow Rates(cfs) Events Existing Proposed %Reduction 2-yr 0.2459 0.1721 30.0% 5-yr 0.3039 0.2033 33.1% 10-yr 0.3426 0.2246 34.4% 25-yr 0.3922 0.2523 35.7% 50-yr 0.4298 0.2736 36.3% 100-yr 0.4679 0.2954 36.9% Harrington NE12th Street to NE 10th Steet.West Side Peak Flow Rates(cfs) Events Existing Proposed %Reduction 2-yr 0.2231 0.1722 22.8% 5-yr 0.2757 0.2029 26.4% 10-yr 0.3108 0.2235 28.1% 25-yr 0.3558 0.2498 29.8% 50-yr 0.3898 0.2697 30.8% 100-yr 0.4244 0.2898 31.7% Harrington Avenue,SR900 to NE 9th Street Peak Flow Rates(cfs) Events Existing Proposed %Reduction 2-yr 0.2898 0.0414 85.7% 5-yr 0.3522 0.0808 77.1% 10-yr 0.3927 0.1205 69.3% 25-yr 0.4431 0.1923 56.6% 50-yr 0.4804 0.2659 44.7% 100-yr 0.5176 0.3616 30.1% Harrington Avenue NE,NE 9th Street to NE 7th Street Peak Flow Rates(cfs) Events Existing Proposed %Reduction 2-yr 0.4485 0.2049 54.3 5-yr 0.5484 0.2605 52.5% 10-yr 0.6133 0.3017 50.8% 25-yr 0.6946 0.3587 48.4% 50-yr 0.7549 0.4049 46.4% 100-yr 0.8151 0.4545 44.2% Appendix E Opinion of Cost RENTON SUNSET PLAN ACTION EIS PROJECT DATE: 10/10/2012 REGIONAL FACILITIES PROJECT NO.:437060 ORDER OF MAGNITUDE ESTIMATE ESTIMATE BY:C Moore REVIEW BY: R Chung TOTAL UNIT TOTAL DESCRIPTION CITY I UNIT COST COST Infiltration Gallery Excavation 2,535 CY $7.68 $19,475 Waste 1,455 CY $14.41 $20,966 Native Backfill 1,080 CY $9.37 $10,125 Bioretention Soil 285 CY $41.41 $11,802 Drain Rock 1,170 CY $39.32 $46,001 Geotextile 2,500 SY $3.00 $7,500 Seeding 1,140 SY $3.76 $4,282 Landscaping 570 SY $25.00 $14,250 8"Perforated Pipe 900 LF $17.83 $16,045 Cleanout 3 EA $350.00 $1,050 CB Type 2,48"dia 2 EA $2,221.59 $4,443 Birdcage Overflow Structure(CB Type 2,48"dia) 1 EA $3,221.72 $3,222 Misc.Detail Allowance 1 LS $15,916.02 $15,916 Infiltration Gallery Subtotal $175,076 Coveyance Line Excavation 924 CY $7.68 $7,095 Waste 924 CY $14.41 $13,308 Pipe Bed and Zone 461 CY $40.98 $18,902 Imported Backfill above Bed and Zone 394 CY $36.66 $14,434 12"RCP Storm Drain 40 LF $43.02 $1,721 18"RCP Storm Drain 1,030 LF $57.29 $59,010 CSBC(6"layer) 99 CY $37.97 $3,766 Sawcutting 1,260 LF $3.50 $4,410 Asphalt Demo over pipe trench 595 SY $9.15 $5,442 Asphalt Patching over pipe,6"depth 203 TON $120.00 $24,419 CB Type 2,48"dia 7 EA $2,221.59 $15,551 Flow Control Structure,72"CB Type 2 1 EA $7,812.55 $7,813 CB Type 1 3 EA $763.87 $2,292 Tie into existing line 3 EA $1,253.39 $3,760 Traffic Control for Pipe in Roadway 10 DAY $620.34 $6,203 Misc.Detail Allowance 1 LS $18,192.01 $18;192 Conveyance Line Subtotal $206,315 SUBTOTAL $381,392 MOB,BONDS,INSUR,TEMP.FACIL,DEMOB,ETC 10.0% $38,139 SUBTOTAL $419,531 CONTINGENCY 30.0% $125,859 CONSTRUCTION TOTAL(ROUNDED) $545,000 SALES TAX 9.5% $51,775 CONSTRUCTION TOTAL(ROUNDED) $597,000 Low range -30.0% $420,000 High Range 50.0% $900,000 NOTE: The above cost opinion is in October 2012 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. RENTON SUNSET PLAN ACTION EIS PROJECT DATE: 10/30/2012 HARRINGTON AVE PROJECT NO.: 437060 NE 16th TO NE 12th ST ESTIMATE BY: C Moore ORDER OF MAGNITUDE ESTIMATE REVIEW BY: R Chung TOTAL UNIT TOTAL DESCRIPTION QTY UNIT COST COST HARRINGTON SEG 1 From NE 16th Street to NE 12th Street East Side Asphalt Demo 3,800 SY $9.15 $34,753 Sawcutting 1,368 LF $3.50 $4,788 Asphalt Patching for Pipes,6"depth 122 TON $120.00 $14,610 Asphalt Patching Restoration,6"depth 128 TON $120.00 $15,308 Pipe Removal 12" 0 LF $21.95 $0 CB Type 1 Removal 0 EA $192.06 $0 Pipe Abandonment, 12" 0 LF $10.00 $0 Excavation 1,159 CY $7.68 $8,901 Waste 1,159 CY $14.41 $16,696 Pipe Bed and Zone 580 CY $40.98 $23,765 Imported Backfill above Bed and Zone 500 CY $36.66 $18,323 12" RCP Storm Drain 375 LF $43.02 $16,131 18" RCP Storm Drain 1,040 LF $57.29 $59,582 CB Type 1 12 EA $763.87 $9,166 CB Type 2,48"dia 8 EA $2,221.59 $17,773 Pervious Conc Sidewalk(asm 4"thick w/4"CSBC) 6,498 SF $8.22 $53,446 Curb&Gutter 1,300 LF $10.75 $13,977 Driveway(asm 6"thick w/8"CSBC, 12'wide,6'long) 936 SF $7.59 $7,104 Bioretention Swale Excavation 781 CY $7.68 $6,002 Waste 781 CY $14.41 $11,258 Bioretention Soil, 18"depth 313 CY $41.41 $12,941 Drain Rock, 15"depth 97 CY $39.32 $3,822 Geotextile 625 SY $3.00 $1,875 Seeding 625 SY $3.76 $2,347 8" Perforated Pipe 450 LF $17.83 $8,023 Planter Area 233 SY $18.86 $4,394 Trees 17 EA $350.00 $5,950 Traffic Control 33 DAY $570.34 $18,821 Misc. Detail Allowance 1 LS $37,093.64 $37,094 West Side Asphalt Demo 2,000 SY $9.15 $18,291 Sawcutting 336 LF $3.50 $1,176 Asphalt Patching for Pipes,6"depth 3 TON $120.00 $369 Asphalt Patching Restoration,6"depth 14 TON $120.00 $1,724 Pipe Removal 12" 237 LF $21.95 $5,202 CB Type 1 Removal 3 EA $192.06 $576 Pipe Abandonment, 12" 765 LF $10.00 $7,650 Excavation 51 CY $7.68 $389 Waste 51 CY $14.41 $730 RENTON SUNSET PLAN ACTION EIS PROJECT DATE: 10/30/2012 HARRINGTON AVE PROJECT NO.: 437060 NE 16th TO NE 12th ST ESTIMATE BY: C Moore ORDER OF MAGNITUDE ESTIMATE REVIEW BY: R Chung TOTAL UNIT TOTAL DESCRIPTION QTY UNIT COST COST Pipe Bed and Zone 26 CY $40.98 $1,049 Imported Backfill above Bed and Zone 23 CY $36.66 $840 12" RCP Storm Drain 75 LF $43.02 $3,226 18"RCP Storm Drain 0 LF $57.29 $0 CB Type 1 3 EA $763.87 $2,292 CB Type 2,48"dia 0 EA $2,221.59 $0 Sidewalk(asm 4"thick w/4"CSBC) 2,241 SF $5.30 $11,887 Curb&Gutter 280 LF $10.75 $3,010 Driveway(asm 6"thick w/8"CSBC, 12'wide,6'long) 0 SF $7.59 $0 Bioretention Swale Excavation 281 CY $7.68 $2,161 Waste 281 CY $14.41 $4,053 Bioretention Soil, 18"depth 113 CY $41.41 $4,659 Drain Rock, 15"depth 42 CY $39.32 $1,638 Geotextile 225 SY $3.00 $675 Seeding 225 SY $3.76 $845 8"Perforated Pipe 150 LF $17.83 $2,674 Planter Area 22 SY $18.86 $415 Trees 5 EA $350.00 $1,750 Traffic Control 9 DAY $570.34 $5,133 Misc. Detail Allowance 1 LS $7,728.33 $7,728 SUBTOTAL $516,996 MOBILIZATION,BONDS,INSURANCE,TEMP.FACILITIES,DEM 10.0% $51,700 SUBTOTAL $568,695 CONTINGENCY 30.0% $170,609 CONSTRUCTION TOTAL(ROUNDED) $740,000 SALES TAX 9.5% $70,300 CONSTRUCTION TOTAL(ROUNDED) $810,300 Low range -30.0% $570,000 High Range 50.0% $1,220,000 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. RENTON SUNSET PLAN ACTION EIS PROJECT DATE: 10/30/2012 HARRINGTON AVE PROJECT NO.: 437060 NE 12th TO NE 10th ESTIMATE BY: C Moore ORDER OF MAGNITUDE ESTIMATE REVIEW BY: R Chung TOTAL UNIT TOTAL DESCRIPTION QTY UNIT COST COST HARRINGTON SEG 2 From NE 12th to NE 19th East Side Asphalt Demo 1,918 SY $9.15 $17,541 Sawcutting 742 LF $3.50 $2,597 Asphalt Patching for Pipes,6"depth 86 TON $120.00 $10,342 Asphalt Patching Restoration,6"depth 22 TON $120.00 $2,586 Pipe Removal 12" 219 LF $21.95 $4,807 CB Type 1 Removal 1 EA $192.06 $192 Pipe Abandonment, 12" 334 LF $10.00 $3,340 Excavation 562 CY $7.68 $4,316 Waste 562 CY $14.41 $8,096 Pipe Bed and Zone 282 CY $40.98 $11,558 Imported Backfill above Bed and Zone 246 CY $36.66 $9,026 12" RCP Storm Drain 396 LF $43.02 $17,035 18" RCP Storm Drain 338 LF $57.29 $19,364 CB Type 1 5 EA $763.87 $3,819 CB Type 2,48"dia 4 EA $2,221.59 $8,886 Pervious Conc Sidewalk(asm 4"thick w/4"CSBC) 2,484 SF $8.22 $20,431 Curb&Gutter 497 LF $10.75 $5,343 Driveway(asm 6"thick w/8"CSBC, 12'wide,6'long) 288 SF $7.59 $2,186 Bioretention Swale Excavation 331 CY $7.68 $2,539 Waste 331 CY $14.41 $4,763 Bioretention Soil, 18"depth 132 CY $41.41 $5,475 Drain Rock, 15"depth 52 CY $39.32 $2,063 Geotextile 264 SY $3.00 $793 Seeding 264 SY $3.76 $993 8" Perforated Pipe 170 LF $17.83 $3,031 Planter Area 222 SY $18.86 $4,187 Trees 12 EA $350.00 $4,200 Traffic Control 17 DAY $570.34 $9,696 Misc. Detail Allowance 1 LS $17,951.09 $17,951 West Side Asphalt Demo 2,392 SY $9.15 $21,876 Sawcutting 310 LF $3.50 $1,085 Asphalt Patching for Pipes,6"depth 13 TON $120.00 $1,518 Asphalt Patching Restoration,6"depth 7 TON $120.00 $821 Pipe Removal 12" 0 LF $21.95 $0 CB Type 1 Removal 0 EA $192.06 $0 Pipe Abandonment, 12" 0 LF $10.00 $0 Excavation 45 CY $7.68 $343 Waste 45 CY $14.41 $643 RENTON SUNSET PLAN ACTION EIS PROJECT DATE: 10/30/2012 HARRINGTON AVE PROJECT NO.: 437060 NE 12th TO NE 10th ESTIMATE BY: C Moore ORDER OF MAGNITUDE ESTIMATE REVIEW BY: R Chung TOTAL UNIT TOTAL DESCRIPTION CITY UNIT COST COST Pipe Bed and Zone 23 CY $40.98 $923 Imported Backfill above Bed and Zone 20 CY $36.66 $739 12" RCP Storm Drain 66 LF $43.02 $2,839 18" RCP Storm Drain 0 LF $57.29 $0 CB Type 1 2 EA $763.87 $1,528 CB Type 2,48"dia 0 EA $2,221.59 $0 Sidewalk(asm 4"thick w/4"CSBC) 1,368 SF $5.30 $7,256 Curb&Gutter 228 LF $10.75 $2,451 Driveway(asm 6"thick w/8"CSBC, 12'wide,6'long) 0 SF $7.59 $0 Bioretention Swale Excavation 199 CY $7.68 $1,526 Waste 199 CY $14.41 $2,862 Bioretention Soil, 18"depth 79 CY $41.41 $3,290 Drain Rock, 15"depth 27 CY $39.32 $1,067 Geotextile 159 SY $3.00 $477 Seeding 159 SY $3.76 $597 8" Perforated Pipe 110 LF $17.83 $1,961 Planter Area 50 SY $18.86 $943 Trees 4 EA $350.00 $1,400 Traffic Control 7 DAY $570.34 $3,992 Misc. Detail Allowance 1 LS $5,614.56 $5,615 SUBTOTAL $272,910 MOBILIZATION, BONDS,INSURANCE,TEMP.FACILITIES,DEM 10.0% $27,291 SUBTOTAL $300,201 CONTINGENCY 30.0% $90,060 CONSTRUCTION TOTAL(ROUNDED) $390,000 SALES TAX 9.5% $37,050 CONSTRUCTION TOTAL(ROUNDED) $427,050 Low range -30.0% $300,000 High Range 50.0% $640,000 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. RENTON SUNSET PLAN ACTION EIS PROJECT DATE: 10/30/2012 HARRINGTON AVE PROJECT NO.: 437060 SR900 TO NE 10th ST ESTIMATE BY: C Moore ORDER OF MAGNITUDE ESTIMATE REVIEW BY: R Chung TOTAL UNIT TOTAL DESCRIPTION QTY UNIT COST COST HARRINGTON SEG 3 From SR900 Street to NE 9th Street East Side Asphalt Demo 2,523 SY $9.15 $23,074 Sawcutting 788 LF $3.50 $2,758 Asphalt Patching for Pipes,6"depth 5 TON $120.00 $657 Asphalt Patching Restoration,6"depth 33 TON $120.00 $3,981 Pipe Removal 12" 0 LF $21.95 $0 CB Type 1 Removal 0 EA $192.06 $0 Pipe Abandonment, 12" 0 LF $10.00 $0 Excavation 24 CY $7.68 $187 Waste 24 CY $14.41 $351 Pipe Bed and Zone 12 CY $40.98 $503 Imported Backfill above Bed and Zone 11 CY $36.66 $403 12" RCP Storm Drain 36 LF $43.02 $1,549 18" RCP Storm Drain 0 LF $57.29 $0 CB Type 1 2 EA $763.87 $1,528 CB Type 2,48"dia 0 EA $2,221.59 $0 Pervious Conc Sidewalk(asm 4"thick w/4"CSBC) 0 SF $8.22 $0 Curb&Gutter 0 LF $10.75 $0 Driveway(asm 6"thick w/8"CSBC, 12'wide,6'long) 288 SF $7.59 $2,186 Bioretention Swale Excavation 161 CY $7.68 $1,238 Waste 161 CY $14.41 $2,322 Bioretention Soil, 18"depth 64 CY $41.41 $2,669 Drain Rock, 15"depth 27 CY $39.32 $1,067 Geotextile 129 SY $3.00 $387 Seeding 129 SY $3.76 $484 8"Perforated Pipe 80 LF $17.83 $1,426 Planter Area 363 SY $18.86 $6,846 Trees 18 EA $350.00 $6,300 Traffic Control 6 DAY $570.34 $3,422 Misc. Detail Allowance 1 LS $5,991.46 $5,991 West Side Asphalt Demo 2,619 SY $9.15 $23,952 Sawcutting 260 LF $3.50 $910 Asphalt Patching for Pipes,6"depth 19 TON $120.00 $2,339 Asphalt Patching Restoration,6"depth 3 TON $120.00 $369 Pipe Removal 12" 0 LF $21.95 $0 CB Type 1 Removal 0 EA $192.06 $0 Pipe Abandonment, 12" 0 LF $10.00 $0 Excavation 70 CY $7.68 $535 Waste 70 CY $14.41 $1,003 RENTON SUNSET PLAN ACTION EIS PROJECT DATE: 10/30/2012 HARRINGTON AVE PROJECT NO.: 437060 SR900 TO NE 10th ST ESTIMATE BY: C Moore ORDER OF MAGNITUDE ESTIMATE REVIEW BY: R Chung TOTAL UNIT TOTAL DESCRIPTION QTY UNIT COST COST Pipe Bed and Zone 35 CY $40.98 $1,441 Imported Backfill above Bed and Zone 31 CY $36.66 $1,154 12"RCP Storm Drain 103 LF $43.02 $4,431 18"RCP Storm Drain 0 LF $57.29 $0 CB Type 1 2 EA $763.87 $1,528 CB Type 2,48"dia 0 EA $2,221.59 $0 Sidewalk(asm 4"thick w/4"CSBC) 873 SF $5.30 $4,631 Curb&Gutter 120 LF $10.75 $1,290 Driveway(asm 6"thick w/8"CSBC, 12'wide,6'long) 0 SF $7.59 $0 Bioretention Swale Excavation 225 CY $7.68 $1,729 Waste 225 CY $14.41 $3,242 Bioretention Soil, 18"depth 90 CY $41.41 $3,727 Drain Rock, 15"depth 33 CY $39.32 $1,311 Geotextile 180 SY $3.00 $540 Seeding 180 SY $3.76 $676 8" Perforated Pipe 120 LF $17.83 $2,139 Planter Area 27 SY $18.86 $509 Trees 5 EA $350.00 $1,750 Traffic Control 7 DAY $570.34 $3,992 Misc. Detail Allowance 1 LS $5,920.58 $5,921 SUBTOTAL $138,447 MOBILIZATION,BONDS,INSURANCE,TEMP.FACILITIES,DEM 10.0% $13,845 SUBTOTAL $152,291 CONTINGENCY 30.0% $45,687 CONSTRUCTION TOTAL(ROUNDED) $200,000 SALES TAX 9.5% $19,000 CONSTRUCTION TOTAL(ROUNDED) $219,000 Low range -30.0% $150,000 High Range 50.0% $330,000 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. RENTON SUNSET PLAN ACTION EIS PROJECT DATE: 10/30/2012 HARRINGTON AVE PROJECT NO.: 437060 NE 9th TO NE 7th ST ESTIMATE BY: C Moore ORDER OF MAGNITUDE ESTIMATE REVIEW BY: R Chung TOTAL UNIT TOTAL DESCRIPTION QTY UNIT COST COST HARRINGTON SEG 4 From NE 9th Street to 7th Street East Side Asphalt Demo 6,060 SY $9.15 $55,423 Sawcutting 1,058 LF $3.50 $3,703 Asphalt Patching for Pipes,6"depth 51 TON $120.00 $6,074 Asphalt Patching Restoration,6"depth 29 TON $120.00 $3,447 Pipe Removal 12" 20 LF $21.95 $439 Pipe Removal 18" 272 LF $25.61 $6,965 CB Type 1 Removal 2 EA $192.06 $384 Pipe Abandonment, 12" 44 LF $10.00 $440 Excavation 663 CY $7.68 $5,096 Waste 663 CY $14.41 $9,558 Pipe Bed and Zone 334 CY $40.98 $13,673 Imported Backfill above Bed and Zone 294 CY $36.66 $10,772 12" RCP Storm Drain 644 LF $43.02 $27,703 18"RCP Storm Drain 262 LF $57.29 $15,010 CB Type 1 5 EA $763.87 $3,819 CB Type 2,48"dia 6 EA $2,221.59 $13,330 Pervious Conc Sidewalk(asm 4"thick w/4"CSBC) 5,841 SF $8.22 $48,042 Curb&Gutter 1,168 LF $10.75 $12,558 Driveway(asm 6"thick w/8"CSBC, 12'wide,6'long) 288 SF $7.59 $2,186 Bioretention Swale Excavation 583 CY $7.68 $4,481 Waste 583 CY $14.41 $8,406 Bioretention Soil, 18"depth 233 CY $41.41 $9,662 Drain Rock, 15"depth 104 CY $39.32 $4,077 Geotextile 467 SY $3.00 $1,400 Seeding 467 SY $3.76 $1,753 8" Perforated Pipe 280 LF $17.83 $4,992 Planter Area 338 SY $18.86 $6,374 Trees 16 EA $350.00 $5,600 Traffic Control 29 DAY $570.34 $16,540 Misc. Detail Allowance 1 LS $28,536.73 $28,537 SUBTOTAL $330,444 MOBILIZATION, BONDS,INSURANCE,TEMP.FACILITIES, DEM 10.0% $33,044 SUBTOTAL $363,488 CONTINGENCY 30.0% $109,046 CONSTRUCTION TOTAL(ROUNDED) $470,000 SALES TAX 9.5% $44,650 CONSTRUCTION TOTAL(ROUNDED) $514,650 RENTON SUNSET PLAN ACTION EIS PROJECT DATE: 10/30/2012 HARRINGTON AVE PROJECT NO.: 437060 NE 9th TO NE 7th ST ESTIMATE BY: C Moore ORDER OF MAGNITUDE ESTIMATE REVIEW BY: R Chung TOTAL UNIT TOTAL DESCRIPTION OTY UNIT COST COST Low range -30.0% $360,000 High Range 50.0% $770,000 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. Appendix F Comment Resolution Form Quality Review Form (Q R F) Category 1:Comment intended to identify significant system deficiencies for phase of review or major design flaws. Reviewers shall only use Rev.1,12-11-2012 this category to include comments that truly are considered serious flaws or life safety issues. If continuous CC review is performed correctly there should be little or no need for this category. Client/Project: City of Renton Category 2:Comment to identify incorrect information found in the review.Comment may also be focused on lowering risk,or Improving the quality of the work product and/or the ultimate application of the work product consistent with the contracted scope and quality management Phase: Sunset Regional Facility and Harrington Green Connections - plan. Pre-design report Work Product: Pre-Design Report D ate: 12/10/12 Category 3:Comment is editorial or otherwise minor in nature with little effort to Implement Intent of this category Is not to spend time discussing these comments during final review discussions. Comment is non-controversial in nature and easily incorporated or may be discretionary with the Task Lead and/or PM. Return to: File Name: Final Adjudication Due Date:December Review Comment Due Date:July 9 Response Due Date: December 2012 2012 Final Adjudication: "Done"if resolved, "ITF"if passed to Issue Tracking Form, Comment Reference Page or Reviewer CAT Responsible "NA"if no action is Number Sheet No. (QR) Review Comment NO. Responder Response required Existing trees have been inspected by an Arborist. To the extent possible,significant trees Several existing trees are proposed to be removed are being preserved. Trees designated to be for the Harrington project which does seem a little counter-productive to installing rain gardens. Trees removed are only those absolutely necessary or 1 All Leslie B. 2"and diameter or less should be replanted in the 3 Dustin A. in poor health.Some of the existing trees may ITF bio-filtration swales and/or at other suitable not be tolerant to water or occasional standing locations. water.More analysis will be done in the next phase of design. The Regional storm water facility in the Predesign Agreed. Surface facility shape will be Report uses the standard rectangular layout with coordinated with selected Landscape Architect. 2 All Leslie B. the traditional side slopes. Please note in the 3 Dustin A. Subsurface infiltration gallery may be ITF written text and on the drawings that the final design will have a more organic layout enhancing rectangular as has surface expression and is the ark features. easier to build and maintain. "Community Services"should replace"Parks 3 All Leslie B. Department/Parks and Recreation Department'in 2 Dustin A. OK.Report will be updated Done all documents Correct. Report should have a summary of PGIS-page 3 of the Design Report-please identify abbreviations.The report currently includes a 4 P.3 Leslie B. (I believe this is Pollution Generating Impervious 3 Dustin A. section of abbreviations.PGIS is included in that NA Surface?) section.Future technical information reports will also include a section of abbreviations. At some point as we move through this process we will need to discuss the on-going maintenance and operations. As Community Services maintains many ROW areas with Contract Landscape Maintenance this approach could be applied to the plant maintenance in the swales along Harrington. Public Works would need to maintain the drainage Noted.Coordination to be conducted in design 5 All Leslie B. improvements of these facilities(swales and piping) 3 Dustin A. phase and among City departments.This item ITF if they are under performing. If plant materials will be addressed in the future stage of design need to be removed for PW to maintain the swales/piping we should have a plan in place for material procurement and replacement costs. Also to be discussed-budgeting for the on-going landscape improvements utilizing contract maintenance. Code for this area is to match existing Page 20 of the Pre-design report,Section 5.1 "The conditions. Therefore to"mitigate"for new target peak flow rate for design of the sub-regional impervious,the target condition is what the facility is to match the peak stormwater runoff from existing condition is where the new impervious 6 p.20 Leslie B. 3 Dustin A. Done the assumed existing non-impervious condition". will be added. In this condition it is assumed Both Ron and I tried to understand this sentence but that those surfaces are grass(either Till or could not. Clarification is needed. Outwash).The report will be revised for carification Depending on the document the"Sunset Regional Will correct.Report will be updated for 7 All Leslie B. Facility"is also referred to the"Sunset Regional 3 Dustin A. clarification.From now on we will refer to the Done Stormwater Infiltration Facility facility as the Sunset Terrace Regional Stormwater Facility It is a fall back option and not the primary The Filterra system is mentioned one time in the pre approach so only included where appropriate. 8 All Leslie B. design report-should this be included elsewhere? 2 Dustin A. Further discussion will be included in the next ITF phase of design and drainage report. 9 Figures Leslie B. All Figures-Please label the Segment location 2 Dustin A. OK.Report will be updated Duna Agree. This will need to be coordinated, The loss of on-street parking along a majority of the communicated and approved as design east side of Harrington Ave NE resulting from the progresses.The proposed improvements to proposed LID improvements is an issue that should Harrington are consistent with the adopted 10 All Bob M. be discussed with Sunset community and abutting 2 Dustin A. Surface Water Master Plan and EIS for Sunset. ITF residents in particular.Other than this concern,this FutherLID project would improve the overall aesthetics of consideration analysis will be done akig under consideration possile alignments that will Harrington. minimize parkign impacts.This comment will be addressed in the next phase of design On page 3,3.Design Criteria,: last bullet at bottom 11 P.3 Bob M. of page-word(s)missing that would add clarity to 3 Dustin A. Will correct.Report will be updated Done sentence after"Harrington Avenue Green Connections". On page 4,4.1.1 Bioretention Swale,first paragraph:suggest adding"becomes"between "structure"and"clogged"for clarity.In section 12 p.4 Bob M. 4.1.2,suggest revising"porous"to"pervious"to be 3 Dustin A. Will correct.Report will be updated Done consistent with Section 1,Project Description on page 1. On page 21,paragraph at bottom of page:suggest OK.Report will be updated.Pervious is the 13 P.21 Bob M. 3 Dustin A. Done "porous"be revised to"pervious". correct accepted terminologyfor concrete. On page 22,Section 6 cost Opinion-suggest "porous"be revised to"pervious"in first 14 P.22 Bob M. paragraph below Table 5.Also,suggest revising the 3 Dustin A. OK.Report will be updated Done beginning of the first sentence in the last paragraph to"In the next phase of design............. Appendix E,Opinion of Cost:the unit cost for excavation seems low(suggest$15/CY),the unit cost for Waste seems low(suggest$25/CY),and the unit cost for curb and gutter seems low(suggest $20/1,F).The estimates do not include a cost for Erosion Control,Pavement Markings,and Signing. 15 Appendix E Bob M. Roadway centerline marking(raised pavement 3 Dustin A. Will review and address in the next phase of ITF markings)will be needed where the existing design centerline marking cannot be maintained and additional centerline marking is needed where none exists,due to the adjustment in roadway width resulting from installation of the raingardens.No Parking signage will be needed at each of the raingardens. Revise report title and report to include the names 16 All Ron S.(SW and to be consistent with the two grant 3 Dustin A. OK.Report will be updated OK agreements that we have for these projects from Ecology t Removal of fecal coliform was included by the City&CH2MHILL in the grant application to Section 1.0-Is the project only improving TSS and address the key water quality issue in Johns Fecal Coliform,won't these facilities remove other Creek.Bioretention removes fecal coliform 17 P.1 Ron S.(SW 3 Dustin A. Done pollutants. How is the project reducing Fecal (typically due to pet waste and birds as sources) Coliform? through filtration and biological breakdown. Report will be revised to briefly summarize treatment provided by the rain gardens. Section 2—Does bioretention facility=rain Yes. Bioretention facility is a more general term IS P.2 Ron S.(SW garden? Is there a reason why we are using 3 Dustin A. typically used regardless of shape.We will Done bioretention facility instead of rain garden? update the report Section 4.2—A minimum 8-inch perforated pipe 19 P.5 Ron S.(SW will be needed not 6-inch. We may want to look at 3 Dustin A. Agree. Will address in design ITF as part of design using 12-inch perforated pipe, especially for the infiltration facility. Is the storm drain line shown in the figure connecting to Sunset Ave a new storm line or is the Existing storm drains are typcially shallow and 20 Fig.1 Ron S.(SW existing storm line going to be used? As part of the 2 Dustin A. may not drain the underdrains where necessary. ITF Will be addressed in greater detail in Design design we may want to evaluate using the existing Phase.Will address in design stormline or installing a new one. Why are we planning to abandon the existing storm line on the west side of Harrington adjacent to the Existing storm drains are typcially shallow and School. This line is relatively new. Why couldn't it may not drain the underdrains where necessary. 21 Fig 2-A Ron S.(SW 2 Dustin A. ITF be used as the conveyance system and eliminate Will be addressed in greater detail in Design installing some of the new storm system as shown Phase.Will address in design on the figure? Planting areas are designated to differentiate between effective rain garden area vs.non- effective(e.g.non ponding/infiltrating). They Same as comment on Figure 2-A and Why are we are necessary to grade in order to create a designing the locations of the planting areas? We consistent curbline and space for rain gardens. 22 Fig 2-B Ron S.(SW 2 Dustin A. ITF will not be making the planting area improvements Project will take this into consideration and only as part of this project. include landscaping necessary for construction of the water quality retrofit in the designation of eligibility for Ecology's reimbursement.Will address in the next phase of design. Why is the proposed new stormlihe adjacent to the sidewalk? Where is the curb for the street going to be located? We will need to evaluate conflicts with 23 Fig 3 Ron S.(SW other City and franchise Utilities as part of design 3 Dustin A. Figure is schematic,final alignment will be Nn to determine relocation requirements. Why can't determined in Design phase. the existing storm system be used instead of abandoning it and constructing a new storm system? Existing storm conveyance system being abandoned. Can it be used to avoid having to install a new storm system. Location of new storm system is adjacent to the sidewalk. Why is it not Existing storm drains are typcially shallow and 24 Fig 5-B Ron S.(SW located adjacent the curb. We need to look at 3 Dustin A. may not drain the underdrains where necessary. ITF cn Will be addressed in greater detail in Design where the new storm system connect to at NE 7 Phase.Will address in design Street. The current connection is to the older system the storm system on the south side of the street is a newer storm system. Code for this area is to match existing conditions. Therefore to"mitigate"for new Section 5.1—The explanation of the Target design impervious,the target condition is what the 25 p.20 Ron S.(SW flow rate is unclear to me. I don't understand what 3 Dustin A. existing condition is where the new impervious Done we are basing the facilities target flow rate on. will be added. In this condition it is assumed that those surfaces are grass(either Till or Outwash).Report will be updated to clarify Does the sizing for the rain gardens and infiltration The infiltration facility is being designed facility assume 100%of the basin tributary area preliminarily with a flow splitter on a portion of 26 Fig A-1 to A-5 Ron S.(SW 3 Dustin A. the inflow,this will allow some flexibility in the ITF drains to the facility? Will this be true under future amount of runoff in the future.Furhter analysis conditions when the sites are redeveloped? will be done in the next phase of design Sub-regional Facility cross-section and Plan drawings—Can 12-inch perforated pipe be used instead of 8-inch? The plan will need to be revised. We will not want bends as shown in the 27 All Ron S.(SW infiltration galley pipes. We will want to have 3 Dustin A. phaSe Will address in the next phase of design ITF connections of all pipe runs or some type of a header system with cleanouts. Does the design as shown meet the pre-treatment requirements for an infiltration facility? Street cross-sections—Verify that these sections match those in the Planned Action EIS. I am Yes. These are based on the complete streets concerned with only 10-ft lanes and 6-ft parking requirements for an access street which require 2 8 All Ron S.(SW 3 Dustin A. ITF strip. The parking strip doesn't seem wide enough. 10-foot lanes and a 6-foot parking lane on one What is the standard design requirements for side. Will address in the next phase of design street parallel parking strip? There is an existing 8-inch City cast-iron water line located in front of the face of the existing east curb line(see water project civil plans W-1878). The designer needs to verify that the proposed bio- Thank you,this will be a significant conflict that Harrington 12th Abdoul G. retention swales and proposed drainage pipes we will need to resolve in the design phase. 29 to 16th (WU) along the east side of the street are not in conflict 3 Dustin A. Please provide the appropriate clearances for ITF final design to avoid these facilities.Will with the existing water line and that adequate address in the next phase of design minimum horizontal separation must be provided between the existing water line and the proposed storm line and related facilities. There are existing water service lines and water meters serving the existing residences along both side of the street. The service lines will have to be replaced as part of the project and sleeves must be 30 Harrington 12th Abdoul G. provided to protect the service lines crossing under 2 Dustin A. Agree,details will be added in the Design phase. ITF to 16th (WU) the proposed bio-retention swales. Existing water meters will have to be relocated and provisions must be made to provide adequate right-of-way or easement for the water meters,since they cannot be located within the bioswales. There is an existing 8-inch City cast-iron water line located in front of the face of the existing east curb line(see water project civil plans W-1878). There is also a new 12-inch water line in Harrington Ave NE Noted.Utility locates and potholing are Harrington 10th Abdoul G. 37 (WU) from NE 12`h St to Glenwood Ave NE(see water 3 Dustin A. included in Design Phase Scope.Will address in ITF to 12th project civil plans W-3606). There is an existing 12- the next phase of design inch asbestos-cement water line along the east side of the road from NE 12`h St to Glenwood Ave(see water project W-1134). The Water Utility would like to include the design and construction of a new 12-inch water line connecting to the above existing 12-inch line at Glenwood Ave NE and extending south to NE 10th St,and also a 12-inch water line in NE 10th St from Harrington Ave NE extending easterly and southeasterly and connecting to an existing 12-inch Noted. Will accommodate inclusion of Harrington 10th Abdoul G. water stub on the north side of Sunset Blvd NE(see 32 3 Dustin A. waterline plans in design documents.Will ITF to 12th (WU) water project civil plans W-3179). The Water address in the next phase of design Utility will design the water line with in-house staff and will use the base map survey provided by the consultant. The Water Utility intends to hold a latecomer agreement or a special assessment district to recoup the cost of this new water line from potential benefiting properties as such time the properties are developed and/or redeveloped. 33 All Erika r D). will the Harrington swales be in the existing ROW? 3 Dustin A. Yes. NA 34 All Erika C. Will they be coordinated into the Complete Streets 3 Dustin A. Yes. NA (CED) standards? This needs to be discussed. Only Harrington How will the project be implemented? Will we Green connections(from NE loth to NE 16th)is Erika C. wait for new development to include this as part of scoped and to be constructed initially. It is 35 All 3 Dustin A. ITF (CED) frontage improvements or will we install the whole presumed that remainder will occur via frontage system at once? improvements or incr.as funding is available through the Ci 's CIP Erika C. If the City does the installation will we need to 36 All 3 Dustin A. Good discussion point. Likely it is needed. 1"1"P (CED) create a Limited Improvement District? The project will infiltrate a minimum of 91%of the average annual runoff volume(through the bioretention soil and into native soils)to meet Hebe B. is it safe to say that the infiltration facility will 3 Dustin A. the water quality target volume. Our NA 37 All (SW) infiltrate 91 percent.of the 100 YR? preliminary analysis shows upward of 99%of the total hydrograph infiltrated,however,the model does not report the%infiltrated of individual events such as the 100-year event. Not sure why we are not using rain gardens as LIDS and instead we are replacing the facility with bioswales.While I can see why we would use the swales along Harrington(conveyance)we have to We are using rain gardens. Just using the Hebe B. keep in mind that the bioswales will not provide generic term bioretention swales which rely on 3fi All 3 Dustin A. NA (SW) enhanced basic water quality treatment. I saw in filtration throught the bioretention soils and the report that we are using the same soil media meets enhanced basic water quality. for the swales sections.Minimum soil amended is 12"with 4"of compost...are we incorporating these measures in the design of the swales? Because of the runoff coming from SR-900,and even when we are not require to provide enhanced 39 All Hebe B. basic treatment in the grant agreement,we should 3 Dustin A. See above. NA (SW) look into doing more of a rain garden there and provide enhance treatment as required in the regional stormwater facility Infiltration rate correction factors for native soil Were in the KC manual is the safety factor used are discussed in Section 5.4.1 of the KCSWDM. Hebe B. discussed?We should not be referring to the DOE The KCSWDM lacks sufficient detail on rain 40 All (SW) manual but the 2009 KCSWDM as amended by the 3 Dustin A. gardens therefore we are using the latest NA guidelines from Ecology,WSU-Puyallup and City. our experience to.define the design infiltration rate for bioretention soil. Code for this area is to match existing conditions. Therefore to"mitigate"for new Hebe B. On the design of the regional facility,was the impervious,the target condition is what the 41 All (SW) predeveloped condition used100 percent grass? 3 Dustin A. existing condition is where the new impervious NA will be added. In this condition it is assumed that those surfaces are grass(either Till or Outwash). Rain gardens(bioretention swales)are using 6 What infiltration rate was used for the design of in/hr for the bioretention soil only. Native soils the regional facility and rain gardens?Was is 6"/hr are using 1.2 in/hr(after factors of safety are Hebe B. for infiltration galleries and 1.2"/hr for the applied)as recommended by the geotechncial 42 All (SW) Harrington LIDs?What is it different?Wouldn't the 3 Dustin A. report where infiltration is feasible. Where NA infiltration rate used for the rain gardens/swales on infiltration is not feasible(due to shallow depth to Till b/w 10th and 12th)an infiltration rate of NE 16th be higher? 0 is assumed with underdrain orifices controlling flow through the facilities. Where are the sizes for the rain gardens on each �,� All Hebe B. cart inn of"cti i lu Aron"?urAc that inrIi irlarl in thic I 3 nimfin A ThP civino farfnrc`erara arlrjaril fn the rPnnrf NTA As the peak intensity of rainfall is generally equal to or less than the design infiltration rate for the native soils,design analysis at this preliminary stage is not necessary. Based on 44 Hebe B. Where is the discussion of the design of the porous 3 Dustin A. experience a gravel storage depth of 4-6 inches (SW) concrete? will be sufficient to infiltrate 100%of the Done rainfall.We will need to revise this report to include at least a cross section of a typical porous concrete sidewalk showing depth of gravel,subgrade,concrete,etc To be included in future design reports. Design refinements will be made to reduce new conveyance systems where needed. The Hebe B. Discussion about needed conveyance drainage master plan conducted capacity 45 (SW) improvements and/or new conveyance systems 3 Dustin A. analysis of the conveyance system. Revisions ITF needed along Harrington? herein will be based primarily on physical geometry of the rain gardens and assuring proper plumbing.Will be addressed in the next phase of design Utility relocations are not specifically included. Hebe B. Does the cost estimate includes utility relocations 3 Dustin A. A generous cost contingency is provided based ITF 46 (SW) when needed? on the level of detail and design progress.Will be addressed in the next phase of design I'm not sure why we included the south segment 2 into this design.I tough we limited the scope of The entire Harrington corridor was evaluated in work to work until NE 9th st.We should talk about the pre-design study to determine the Hebe B. the south segments and the possibility of those appropriate level of implementation given 47 3 Dustin A. available funds would be necessary to meet NA (SW) segments being constructed in the future.Looking targets. Due to the this analysis and the at the budget provided,we are will not be able to available budget the design will progress construct the 4 segments in the next few years focusing only on the north segment. with the budget we have included in the 6 year CIP. 48 Final Technical Information Report Sunset Community Low Impact Development Retrofit Project Sunset Terrace Regional Stormwater Facility Prepared for City of Renton March 18, 2015 CH2MH I LL o 1100 112th Ave NE Suite 500 Bellevue, WA 98004 b 87 Contents Section Page Acronyms and Abbreviations....................................................................................................................v 1 Project Overview......................................................................................................................1-1 1.1 Existing Site Conditions.......................................................................................................... 1-1 1.1.1 Existing Utilities......................................................................................................... 1-1 1.1.2 Soils........................................................................................................................... 1-1 1.2 Proposed Conditions.............................................................................................................. 1-2 2 Conditions and Requirements Summary....................................................................................2-1 2.1 General................................................................................................................................... 2-1 3 Offsite Analysis.........................................................................................................................3-1 3.1 Task 1 Study Area Definition and Maps................................................................................. 3-1 3.2 Task 2 Resource Review......................................................................................................... 3-1 3.3 Task 3 Field Inspection........................................................................................................... 3-1 3.4 Task 4 Description of Existing Drainage System.................................................................... 3-1 3.5 Task 5 Mitigation of Existing or Potential Problems.............................................................. 3-1 4 Flow Control and Water Quality Facility Analysis and Design......................................................4-1 4.1 Part A- Existing Site Hydrology.............................................................................................. 4-1 4.1.1 Threshold Discharge Areas....................................................................................... 4-1 4.2 Part B-Developed Site Hydrology......................................................................................... 4-1 4.3 Part C-Performance Standards ............................................................................................ 4-1 ` 4.3.1 Flow Control.............................................................................................................. 4-1 4.3.2 Conveyance............................................................................................................... 4-2 4.3.3 Water Quality............................................................................................................ 4-2 4.4 Part D - Flow Control System................................................................................................. 4-3 4.5 Part E -Water Quality System ............................................................................................... 4-3 5 Conveyance System Analysis and Design ...................................................................................5-1 5.1 Existing Storm Drains............................................................................................................. 5-1 5.2 Proposed Storm Drains.......................................................................................................... 5-1 5.3 Utilities................................................................................................................................... 5-2 6 Special Reports and Studies.......................................................................................................6-1 7 Other Permits...........................................................................................................................7-1 8 ESC Analysis and Design............................................................................................................8-1 8.1 ESC Measures......................................................................................................................... 8-1 8.2 ESC Implementation .............................................................................................................. 8-2 8.2.1 ESC Plan..................................................................................................................... 8-2 8.2.2 Wet Season Construction ......................................................................................... 8-2 8.2.3 Construction in Sensitive Areas and Buffers............................................................. 8-2 8.2.4 Maintenance Requirements..................................................................................... 8-2 8.2.5 Final Stabilization...................................................................................................... 8-2 8.2.6 Roads and Utilities.................................................................................................... 8-3 9 Bond Quantities, Facility Summaries,and Declaration of Covenant 9-1 WBG103114153300SEA p1 CONTENTS,CONTINUED Section Page 9.1 Bond Quantities......................................................................................................................9-1 9.2 Facility Summaries..................................................................................................................9-1 9.3 Declaration of Covenant.........................................................................................................9-1 10 Operations and Maintenance Manual......................................................................................10-1 11 References..............................................................................................................................11-1 Appendixes A TIR Table B Facility Hydrological Analysis(WWHM) C Conveyance Calculations and Flow Splitter D Downstream Storm Drain Capacity E Design Drawings Tables 4-1 Regional Stormwater Facility Tributary Areas.....................................................................................4-1 4-2 WWHM Model Input for the Sunset Terrace Regional Facility...........................................................4-4 Figures 1-1 Vicinity Map.........................................................................................................................................1-3 1-2 Soils Map.............................................................................................................................................1-S 1-3 Project Drainage Basins.......................................................................................................................1-7 IV WBG10 31141 5 3 300SEA Acronyms and Abbreviations Ac Acre Ac-ft acre-feet BMP best management practice CFS cubic foot per second Ecology Washington State Department of Ecology ESC erosion and sedimentation control Ft foot GPM gallons per minute KCSWDM 2009 King County, Washington Surface Water Design Manual LID low-impact development NPDES National Pollutant Discharge Elimination System PGIS pollution generating impervious surface RCP reinforced concrete pipe RdC Ragnar-Indianola association soil ROW right-of-way SCS Soil Conservation Service SR State Route SWM Surface Water Management TDA threshold discharge area TIR technical information report Ur Urban Soil WSDOT Washington State Department of Transportation WWHM Western Washington Hydrology Model WBG103114153300SEA V SECTION 1 Project Overview Located in Renton, Washington, this project will provide water quality treatment and infiltration to runoff from the existing roadways using a sub-regional low impact development(LID) facility.The technical information report (TIR)worksheet in Appendix A lists the general project elements. Figure 1-1 shows the project vicinity. The City of Renton (City)completed and adopted the Draft Sunset Area Community Planned Action NEPA/SEPA Environmental Impact Statement(City of Renton, 2010a) in 2010, which included the adoption of the Sunset Area Surface Water Master Plan (City of Renton, 2011).The Sunset Area Surface Water Master Plan identifies areas where green connection improvements could be made at locations that fit with existing and planned future land use in the area and the construction of a regional stormwater facility.These improvements will retrofit existing storm systems in the area to reduce the quantity and improve the quality of stormwater runoff from the existing and future land use within the Sunset Community Plan Area, which discharge to Johns Creek and Lake Washington. While providing enhanced treatment per Ecology standards (Ecology 2014),the proposed practices also provide significant reduction of fecal coliform,typical average reductions of up to 90 percent (Rusciano, 2007), which is a significant contributor to water quality issues at Johns Creek and Coulon Park in Lake Washington. The regional stormwater facility consists of constructing an infiltration flow control facility with a bioretention stormwater facility providing water quality treatment.The green connections retrofit project is completed under a separate scope of work. 1 .1 Existing Site Conditions The project site is located in the Sunset Area in the City of Renton and consists of mixed single-family and multifamily residential and commercial neighborhoods with adjacent schools and public lands.The terrain is relative flat,with a less than 5 percent slope toward the south. Both project areas drain to Johns Creek and Lake Washington. The proposed regional stormwater facility will be co-located with a proposed City of Renton neighborhood park, which is located west of Sunset Boulevard between NE 10th Street and Sunset Court.This site is currently owned by Renton Housing Authority(RHA) and occupied by multifamily housing units.The existing housing will be relocated, and the site will be converted into a public park. Currently,the surface water runoff from this site generally drains overland to the southwest and is collected in existing storm drains in Harrington Avenue NE. Harrington Avenue NE will be vacated as part of the planned park development. 1.1.1 Existing Utilities Existing utilities along Harrington Ave NE, NE 10th Street and Sunset Lane NE include: • Sanitary sewer owned by the City of Renton • Water owned by the City of Renton • Overhead power owned by Puget Sound Energy(PSE) 1.1.2 Soils Soils at the site are mapped as Ragnar-Indianola association, sloping (RdQ according to USDA(2013) soil mapping. Ragnar-Indianola association soils are classified as Hydrologic Group A soils, and are characterized as relatively permeable outwash soils with a high capability to transmit water. Soils immediately adjacent to the bioretention site, on the east side of the existing Sunset Ln, are mapped as Arents, Alderwood material, 6 to 15 percent slopes (AmC). Soils to the north and west of the site are mapped as Urban land (Ur). The Arent soil is classified as Hydrologic Group B soil,and Urban is classified as WBG103 1141 5 3 3 00SEA 1-1 SECTION 1 PROJECT OVERVIEW Hydrological Group C soil.Arent consists of moderately drained material from basal till.The material is classified with low to moderately low capability to transmit water.The Urban soil type is characterized as relatively impermeable glacial till overlain by weathered sand and gravel.See Figure 1-2. Ten borings and two test pits were dug to determine the soil composition. One selective grain size distribution and four field infiltration tests were performed in two of the borings and all of the test pit locations.The grain size distribution tests were performed in accordance with the American Society for Testing and Materials (ASTM) Method D42Z Standard Test Method for Particle-Size Analysis of Soils (ASTM, 2007). One boring (B-10-12)was completed near the proposed stormwater facility location. In this boring, Soil Unit 1 (loose to dense silty sand (SM), silty sand with gravel (SM), silt with sand (ML), and poorly graded sand (SP)) was encountered up to a depth of 20 feet.Groundwater was encountered at 20 feet below ground surface. The infiltration test was performed in the test pit TP-2-12 located near the proposed stormwater facility location.The measured infiltration rate using modified testing was 10.7 in/hour.After applying a safety factor,a design infiltration rate of 1.2 in/hour was assumed. The sieve sizing data from boring B-10-12 sample SS6 indicated that the native soil is silty sand with approximately 38 percent fines (passing the#200 sieve), 53 percent sand (passing sieves between#4 to #200), and 8 percent gravel.The soil log indicated that this soil layer extends up to 20 feet below the existing ground.The median grain size is 0.15mm. Detailed soil information and boring locations can be found in Sunset Stormwater Retrofit Low-Impact Development Project Geotechnica/Data and Recommendations Report(CH2M HILL, 2012a). 1 .2 Proposed Conditions The regional stormwater facility is proposed to infiltrate the equivalent of 2.9 acres of impervious surface area. Most of the impervious area (approximately 2 acres)will be from Sunset Boulevard and NE 10th Street. Additional area from the Greater Highland Shopping Center north of NE 10th Street will make up to the remainder of the targeted 2.9 acres.A new conveyance system will be installed along NE 10th Street to convey water from the Sunset Boulevard storm drain system (north/west side)to the new facility.The total tributary area from the Greater Highland Shopping Center(5.4 acres)exceeds the target area of 2.9 acres. Therefore,a flow splitter manhole will be installed to divert the targeted volume of stormwater runoff from the combined tributary area (shopping center and NE Sunset Boulevard)to the facility.The flow splitter is designed to proportionally divide all design flows (6-month,2-year, 10-year, 25-year, and 100-year) between the proposed regional facility and the bypass to the existing storm drain system. Flows exceeding the design flows for 2.9 acres of impervious area will be diverted back to the existing storm drain system in NE10th Street.The elevation of the outlet to the regional facility is lower than the elevation of the bypass outlet by 1 inch such that the very low flow from the entire tributary area will be diverted to the bioretention cells for treatment. Flow splitter calculations are provided in Appendix C. See Figure 1-3 for a map of the project drainage basins. The facility is proposed at the northeast corner of the future Sunset Park.The bioretention cells will be landscaped with water-tolerant plants, and the rest of the surface above the infiltration gallery will be graded and seeded so that it will be usable space for the park. 1-2 WBG103114153300SEA SECTION 2 Conditions and Requirements Summary 2.1 General This project is subject to the terms and conditions of the FY 2012 Statewide Stormwater Grant Program Funding Agreement with the City(Grant Agreement Number G1200544). Otherwise,there are no known pre-approval conditions associated with the project. The City has adopted the 2009 King County, Washington,Surface Water Design Manual(KCSWDM) along with the City of Renton Amendments to King County Surface Water Design Manual(2010b)for the design of stormwater facilities in the City. See Performance Standards in Section 4.3 of this report for information about the City's flow control, conveyance, and water quality requirements applicable to the project. W BG 103114153300SEA 2-1 SECTION 3 Offsite Analysis The analysis consists of the five tasks presented below, which are outlined in the KCSWDM. 3.1 Task 1 Study Area Definition and Maps The study area for Tasks 3 through 5 extends to 1/4-mile downstream of the downstream discharge point on NE Sunset Boulevard. Refer to Section 1 for a description of existing drainage systems.The existing drainage system consists of a buried pipe network. 3.2 Task 2 Resource Review Drainage basin information near the project was gathered using the following resources: • City of Renton GIS information including stormwater system and sensitive areas maps • Soil Survey, King County Area, Washington, U.S. Department of Agriculture, Soil Conservation Service, 1973, Section 1, Figure 1-2,shows project area soils(no unusual soil conditions within the project limits were noted) • Zoning and wetland information in the City's GIS database, including the Wetlands Inventory Map (no wetlands within the project limits were noted) • Sunset Area Surface Water Master Plan (2011) The project engineers completed a limited site reconnaissance in 2012 to evaluate the upstream drainage conditions. No basin reconnaissance reports or maps were noted, and the City did not communicate any major road drainage problems. 3.3 Task 3 Field Inspection This task was performed using information in the GIS maps and data obtained from the City.The storm drain system 1/4 mile downstream from the project is contained within existing storm drain pipes. No issues with erosion or capacity problems were reported by the City. A system capacity analysis was conducted in the Sunset Area Surface Water Master Plan (CH2M HILL 2011). 3.4 Task 4 Description of Existing Drainage System Refer to Section 1 for the description of the existing drainage system. 3.5 Task 5 Mitigation of Existing or Potential Problems The proposed project is a retrofit project and will reduce the stormwater flow rate and pollutants for the project area. WBG103114153300SEA 3-1 SECTION 4 Flow Control and Water Quality Facility Analysis and Design 4.1 Part A - Existing Site Hydrology 4.1.1 Threshold Discharge Areas The surface water runoff from this site generally drains overland to the southwest and is collected in existing storm drains. Based on the offsite analysis described above in Section 3, a threshold discharge areas(TDA) was identified for the proposed facility. Overland runoff from the Greater Highland Shopping Center and NE 10th St is collected in catch basins and flows west along NE 10th St to Harrington Avenue NE,which will be vacated at this location as part of the planned park developments. Runoff from NE Sunset Boulevard is collected in catch basins and pipes running southwest along NE Sunset Boulevard. 4.2 Para B - Developed Site Hydrology The tributary area to the facility is public right of way on Sunset Boulevard (State Route [SR] 900), NE 10th Street and the proposed King County Library, and also private property on the Greater Highland Shopping Center. Stormwater runoff from Sunset Boulevard,the eastern portion of NE 10th St, and a portion of the future library property will be collected into a new 18-inch storm drain and routed to the flow splitter.This flow splitter will also receive runoff from the Greater Highland Shopping Center TDA via an existing CB and new 18-inch storm drain, redirecting the equivalent flow from approximately 0.77 acres of the 5.35 acre site to the regional facility. Runoff from the western portion of NE 10th Street will be conveyed directly to the facility via a new curbline CB and 18-inch storm drain. TABLE 4-1 Regional Stormwater Facility Tributary Areas Sunset Terrace Regional Stormwater Facility Location Impervious Area(acres) NE Sunset Boulevard 1.79 NE loth St(directly to facility) 0.10 Proposed King County Library&NE lost St 0.24 Greater Highland Shopping Center 0.77(14%of total area) Total to Facility 2.90 4.3 Part C - Performance Standards Performance standards for the project were identified in earlier design deliverables, which were discussed with City staff and documented in the Sunset Area Low-Impact Development Retrofit Improvements—Pre- Design (CH2M HILL, 2012b).The following describe the performance standards to be used for flow control, water quality, and conveyance.The bioretention cells were modeled using Western Washington Hydrology Model, Version 4,with hourly time steps(Ecology 2012). 4.3.1 Flow Control The project is a retrofit that will not add any new impervious area and will not increase the size of any existing impervious area. W BG 103 11 41 5 3 300SEA 4-1 SECTION 4 FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN 4.3.1.1 Pre-developed Site Conditions The 2009 KCSWDM (Section 1.2.3.1) and City of Renton amendment (City of Renton 2010b) specifies predeveloped site conditions as existing conditions. 4.3.1.2 Surfaces Subject to Flow Control The KCSWDM (Section 1.2.3) requires flow control for stormwater runoff from the new impervious surfaces, and new pervious surface that is not fully dispersed.The proposed improvements will reduce the amount of new and replaced impervious surface;therefore,the project is exempt from KCSWDM Core Requirement 3 (see further discussion in Section 4.3.1). 4.3.2 Conveyance The project's stormwater conveyance facilities will consist primarily of catch basins and storm drains.The capacity of the new and existing storm drains will be analyzed using uniform flow methods according to KCSWDM Section 4.2.1.2. 4.3.2.1 Proposed Storm Drains All new conveyance systems will be designed for the 25-year storm. Uniform flow conditions will be used to initially size pipes for capacity. Final pipe sizes will be determined from simple backwater analysis. Excel spreadsheets will be used in both analyses, with the following assumptions: • Pipe material—Smooth wall pipe (concrete or ductile iron pipe) with Manning's n= 0.014 (uniform) and 0.012 (backwater) • Minimum pipe diameter—12 inches • Minimum cover—2 feet; if lower cover is needed, use class 5 reinforced concrete pipe (RCP) or ductile iron pipe • Minimum velocity: 3 feet per second (fps) • Match crowns at junctions with changes in pipe diameter where possible The project will be designed to use drainage structures from Washington State Department of Transportation (WSDOT)Standard Plans. In general,Type II CBs will be used.Type II CBs are typically used where: • Storm drain pipe diameters are 18-inch and greater(exception:Type 1L CB's will be used with 18 inch pipe where depths allow) • Connection angles between the pipe and the CB wall are less than 75 degrees • The invert of the pipe is more than 5 feet below the finished grade 4.3.2.2 Inlets on a Continuous Grade The new inlets used on this project are catch basins with vaned grates. Inlet capacity was not analyzed because the roadway tributary area (NE 10th St) is relatively small. 4.3.2.3 Sag Inlets There are no sag inlets used on this project. 4.3.3 Water Quality The project will not add new pollution generating impervious surface (PGIS)that is not fully dispersed. Therefore no water quality treatment is required. However, water quality treatment is inherent to the design of this project. 4-2 WBG103114153300SEA SECTION 4 FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN 4.4 Part D - Flow Control System The primary purpose of bioretention is to provide pre-treatment of flow prior to the infiltration gallery and to provide water quality treatment of overflows should clogging occur.The two proposed bioretention cells also provide flow control via infiltration and some storage volume within the cells themselves.An 18-inch diameter pipe will connect the two cells to allow their ponding depths to equalize. High flows will be controlled through the outlet structure, overflow structure, and emergency overflow structure shown in the drawings. Within Cell 1,flows exceeding the water quality flow(6 inches of ponding) will overflow into an overflow catch basin (elevation 337.0 feet) and directly into the infiltration gallery.With the selected design (long term) infiltration rate of 1.2 inches/hour, approximately 99.9%of the historical annual runoff volume entering the facility is predicted to infiltrate into the native soil. The maintenance manholes on the east end of the underdrain are connected by 18-inch storm drain to form a manifold.The downstream outlet structure is a 60-inch diameter flow control structure with a riser pipe. The top of the riser(overflow elevation) is set at the top of the mineral aggregate layer such that the runoff will preferentially infiltrate to the native soil, and flows exceeding its total storage will overflow to the downstream storm drain.The emergency overflow structure within Cell 1 with a rim elevation of 337.25 feet will also provide conveyance during extremely large storm events or when the overflow structure or the flow control system is clogged. 4.5 Part E - Water Quality System Bioretention cells are open swales or cells with a wide bottom and are planted with native vegetation. Each cell is composed of two parts, the pre-settling cell and the treatment cell. Most of the flow enters into the bioretention cell 1 is through the flow splitter upstream,only a few percentage of flow is enter directly to bioretention cell 2.At the proposed facility, a a large pre-settling pool is included in Cell 1.The pre-settling area is intended to remove larger debris and disperse the concentrated stormwater runoff from the roadway.The pre-settling area is not included in the calculation of the area for water quality treatment.The rest of the cell area will provide treatment as water flows through the bioretention soil mix. The 18-inch layer of bioretention soil to be installed in each cell has higher porosity and organic content, higher water retention, and increased permeability to enhance the available storage and infiltration of the cells compared to native soil. The 34-inch to 36-inch mineral aggregate layer will provide storage and distribute flows within the gallery. In addition, a 12-inch thick sand layer treatment liner will be installed directly beneath the infiltration gallery per the 2009 KCSWDM (Section 6.2.4.2) and City of Renton amendment(City of Renton 2010b). According to the 2006 Washington State Department of Ecology(Ecology) Guidance for UIC Wells that Manage Stormwater, underground injection control (UIC)wells may be used to manage stormwater (Ecology publication 05-10-067, December 2006).The following key requirements (with references to specific sections)from this Ecology guidance apply to the Sunset Terrace Regional Stormwater Facility: • UIC wells may be used to manage stormwater facility overflow that is greater than the runoff treatment design storm without providing further treatment. [Section 2.1] • UIC wells and other combinations of stormwater facilities must be capable of handling the water quality design runoff treatment storm volume,as well as the amount of runoff predicted from the 6-month, 24- hour storm. [Section 3.2.3] • Oil control should be provided for commercial parking and streets with an average daily traffic (ADT) greater than 7,500. [Section 5.2.4.3] • The soil's vadose zone may provide adequate filtration, adsorption, and other pollutant reduction capacity to meet the non-endangerment standard for solids, metals, oil, grease,and polycyclic aromatic hydrocarbons (PAHs)for groundwater.Table 5.2 of Ecology's guidance lists the vadose zone treatment WBG103114153300SEA 4-3 SECTION 4 FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN capacity classification based on the native soil.The native soil type at the Sunset Terrace Regional Facility site meets the medium classification of the vadose zone treatment capacity classification. [Section 5.3] • The stormwater contributing area is covered by a major arterial road (Sunset Boulevard) and a commercial parking lot. Sunset Boulevard's ADT is less than 30,000.According to Table 5.3 of Ecology's guidance,the corresponding pollutant loading classification for solids, metals, and oil in stormwater runoff directed to UIC wells is medium. According to Table 5.4 of Ecology's guidance, a two-stage dry well is required for pre-treatment.A two-stage dry well is defined as catch basin or other pre-settling/spill control structure that traps small quantities of oils and solids.The native soil is generally silty sand (SM) according to the geotechnical classification,or sandy loam according to the USDA textural triangle method. Its measured infiltration rate of 10.7 in/hr is reasonably close to the 9 in/hour required by the City of Renton,given the variability of the in-situ testing. The gravel and sand components of the native soil also meet the City of Renton's Surface Water Design Standards requirement. In addition,this project proposes a 12-inch sand treatment liner beneath the infiltration gallery with specifications per the 2009 KCSWDM. Therefore,given the proposed treatment liner and the native soil conditions at the site(described above), the runoff managed by the facility is expected to be sufficiently treated before reaching the groundwater and meet Ecology's underground injection well (UIC) requirements. WWHM Modeling Input Table 4-2 lists the model input for the bioretention cells used in the WWHM analysis for this project.The 10,500-square-foot-infiltration gallery(modeled as an infiltration bed) consists of a 36-inch thick layer of type 26 mineral aggregate with 30% porosity. Five 12-inch diameter slotted underdrain pipes at approximately 15-foot spacing at a bottom slope of 0.3%within the level aggregate layer is expected to encourage uniform water distribution throughout the gallery.Spacing and placement at the north portion of the infiltration gallery varies (as shown on the drawings)to accommodate the irregular shape, which is necessary to accommodate a future pergola structure in the park master plan.The WWHM model input and output is included in Appendix B. TABLE 4-2 WWHM Model Input for the Sunset Terrace Regional Facility Bioretention Soil Orifice Bottom Area Freeboard Effective Total Side Slopes Infiltration Ratea Size Element (square feet) (feet) Depth(feet) (H/V) (inches/hour) (inches) Bioretention 1,350 1.0 6 3 1.5 12.0 Cells 1 and 2 ,The long-term design infiltration rate(the design incorporated a safety factor of 8 from the short-term field-tested infiltration rate). Modeling Results The following are summary of the WWHM modeling results • Total Volume Infiltrated: 678 ac-ft • Total Volume Treated with Bioretention Soil: 502 ac-ft • Percent Volume Treated with Bioretention Soil: 72.6% The total volume treated is the runoff volume that passes through the bioretention soil and into the mineral aggregate infiltration layer.The total volume infiltrated is the runoff volume from the infiltration layer entering the treatment liner and then the native soil. 4-4 WBG1031141S3300SEA SECTION 4 FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS AND DESIGN • The water quality peak flow rate (adjusted for 15 minutes) =0.388 cfs. • Design water level: • 2-year=0.58' • 10-year=0.59' • 100-year=0.62' In the December 2014 revision of the Stormwater Management Manual for Western Washington, Ecology has recommended using an initial design infiltration rate of 12 inches per hour, and a long-term rate of 3 inches per hour(safety factor of 4 for contributing areas greater than 10,000 square feet), and a long-term rate of 6 inches per hour(safety factor of 2 for contributing areas with a pretreatment upstream).The 1.5 inches per hour used as model input for the Sunset Terrace Regional Facility bioretention (Table 4-2) is therefore conservative beyond the requirements of the updated Ecology guidance, and the percentage of runoff to be treated will be higher than the current model with a lower percentage of runoff overflow into the overflow structure. Using design infiltration rate of 3 inches per hour yields an 84%treated flow volume while using 5 inches per hour yields exceed 92%treated flow volume. WBG103114153300SEA 4-5 SECTION 5 Conveyance System Analysis and Design This section describes assumptions and site conditions to justify the conveyance design. Permanent conveyance facilities will include catch basin inlets, manholes, and 12-to 18-inch-diameter storm drains. 5.1 Existing Storm Drains As described in KCSWDM Section 1.2.4.2, existing storm drains will be analyzed for the 10-year peak design flow if utilized. Pipes will not be inspected system-wide.The existing storm drain will generally remain in place except the changes described below. The existing storm drain along 10th Street and Harrington Avenue (north of Sunset LN)will receive approximately 1 acres less of stormwater runoff for the runoff will be diverted into the new stormwater facility.Therefore,the existing system should have adequate capacity, and no additional analysis was performed. The existing storm drain along Harrington Avenue downstream of Sunset LN could receive an addition 1.9 acres of stormwater runoff assuming the regional stormwater facility has failed to provide any flow control. That existing storm drain system on Harrington Avenue just upstream of the intersection with Sunset Blvd currently conveys stormwater flows from an estimated 18 acres of roadway,commercial, and residential areas into a 12-inch diameter storm drain.To evaluate the effect of the proposed regional facility,which will add 2 acres of stormwater tributary area to this system, MGS Flood was used to calculate the peak flows rates from the existing contributing area to this storm drain, and the pipe capacity was then calculated. The estimated flow from the entire contributing area before project improvement is approximately 10.2 cfs for the 25-year storm event, and 11.4 cfs for the post project improvement. Since the downstream system has an 24-inch pipe,this existing pipe should be in inlet control condition.The analysis showed that the existing storm drain is undersized for the pre-improvement estimated peak flow from the contributing area. The flow will surcharge inside of the structure.The post-project flow is slightly increased. Using inlet control, the head water of the post-project flow will surcharge approximately 1 additional foot. Since the pipe is approximately 7 feet deep, and the inlet control head is 6.2 feet.The flow should be contained inside the system in the 25-year storm event. However,there is no existing flooding conditions, it is suspected that flat topography within the contributing area, as well as upstream storm drains may be slowing storm flows and preventing this peak flow from reaching the 12-inch storm drain on Harrington Avenue.The flow analysis is included in Appendix D.This existing storm drain should be monitored and could be upsized in a future project. The proposed facility will infiltrate the majority of runoff volume into native ground from the 2.9 acres of tributary area,that the contributory area to the existing storm drain system on Harrington Ave is reduced by approximately 1 acre. If the proposed facility cannot infiltrate the majority of the runoff volume due to unexpected soil conditions,the outlet structure can be modified to include a riser pipe with orifice to provide flow control and reduce overall peak flow rates. 5.2 Proposed Storm Drains As described in Section 4.2 of this report (Developed Site Hydrology), new storm drains will be constructed at the standard location under the curblines and connecting to existing structures.The conveyance systems proposed are primarily catch basins and storm drains.A new storm drain system is proposed on the east side of NE 10th St to collect storm flows from Sunset Boulevard, NE 10th St, and a portion of the planned King County library property.This includes abandoning the existing storm drain system along Sunset Boulevard just south of NE 10th St. A new storm drain connection will replace the existing CB and direct WBG103 11 41 5 3 300SEA 5-1 SECTION 5 CONVEYANCE SYSTEM ANALYSIS AND DESIGN storm flows from the Greater Highland Shopping Center into a flow splitter through a new 18-inch storm drain.The flow splitter will send flows required for treatment and retention of 2.9 acres to the proposed bioretention cells at the Sunset Terrace Regional Facility, and higher flows back into the existing storm drain system in Harrington Avenue NE.A new storm drain at the west portion of NE 10th St will collect runoff from the street and convey it directly into the proposed bioretention cells.The system will consist of 12-inch-to 18-inch-diameter pipes with generally 4 to 5 feet of cover. Calculations in spreadsheet format and accompanying figures for the storm drains are provided in Appendix C.The proposed storm drain configuration is shown and detailed on plan sheets in Appendix E. 5.3 Utilities There are existing storm drains, sanitary sewer,gas,telephone, power, and waterlines along both sides of Harrington Avenue NE. The preference is to place new storm drains under the new curb/gutter line.This is proposed where no utility conflicts are noted. Potholing will be performed to identify the location and depth of the utilities.The design may work around the existing utilities or the utilities will be relocated. 5.2 WBG103114IS3300SEA SECTION 6 Special Reports and Studies The following report was prepared for the project: • Sunset Storm water Retrofit Low-Impact Development Project Geotechnica/Data and Recommendations Report(CH2M HILL 2012a) • Sunset Area Surface Water Master Plan (CH2M HILL 2011) WBG10 31141 5 3 300SEA 6-1 SECTION 7 Other Permits The following permits or approvals are anticipated for the project: • General Construction Stormwater Permit, Notice of Intent—Department of Ecology • Clearing and Grading Permit—City of Renton WBG10 3 1141 5 3 300SEA 7-1 SECTION 8 ESC Analysis and Design An Erosion and Sedimentation Control (ESC) plan will be developed for the contract plans in accordance with the City amendments to KCSWDM (2010) and KCSWDM Appendix D. To avoid erosion and the transport of sediment offsite,the contractor will implement temporary control measures during the construction phase of the project. During construction, stormwater runoff will be conveyed in the existing conveyance systems, which are primarily storm drains. ESC measures will be needed to prevent runoff from causing erosion and discharging sediment into the existing drainage system during and after construction. Appropriate ESC measures will be needed for construction activities on existing storm drain systems.The contractor will be responsible for the phasing of erosion and sediment control measures so that they are coordinated with the staging of construction activities.Additionally,the contractor will be responsible for inspection and maintenance of temporary controls during construction, including removal of accumulated sediment, and for the removal of the controls and remaining accumulated sediment at the end of construction. The project will follow the requirements listed in the National Pollutant Discharge Elimination System (NPDES) General Construction Stormwater Permit.The contractor will prepare a stormwater pollution prevention plan (SWPPP) following the 12 elements listed in the KCSWDM, and the SWPPP will be updated as site conditions change. Permanent measures will be implemented where needed to stabilize disturbed soils at project completion. 8.1 ESC Measures The following ESC measures will be provided, as further detailed on ESC plan sheets: • Clearing Limits—Clearing limits will be delineated on the construction plans.Silt fence or wattles will be installed down slope of any fill slopes to prevent offsite sediment migration. • Cover Measures—The contractor will provide temporary and permanent cover measures where needed to protect disturbed areas. Mulching will be used in accordance with the KCSWDM's Erosion and Sediment Control Standards Appendix D to provide immediate,temporary protection from erosion and to enhance plant growth. Nets and blankets may be used according to Erosion and Sediment Control Standards Addendum D to provide additional protection and to hold seed and mulch in place on slopes. Disturbed areas will be seeded as a permanent cover measure to reduce erosion. • Perimeter Protection—To reduce the transport of sediment off site,the contractor will provide catch basin filters and/street sweeping as indicated on the drawings and as needed. • Sediment Retention—Catch basin filters with the dimensions shown on the drawings will provide sediment retention at the locations shown on the drawings. • Surface Water Control—Surface water control will be provided by using the existing and new drainage conveyance systems. No base flows are expected while the proposed facility is installed. However,any flows encountered should be diverted around the construction. A temporary sandbag berm as shown on the drawings will be used to prevent surface runoff from flowing into the excavated infiltration gallery during construction. • Dust Control—If necessary,the contractor will use water according to KCSWDM Section 3.8 to prevent wind transport of soil. Exposed soils will be sprayed until wet and resprayed as needed. When using water for dust control,the contractor will spray exposed soils until they are wet, but runoff should not be generated by spraying. Oil shall not be used for dust control.At the contractor's option, a tackifier may be used with approval from the Engineer and the City of Renton. W BG 103 11 41 5 3 300SEA 8-1 SECTION 8 ESC ANALYSIS AND DESIGN 8.2 ESC Implementation 8.2.1 ESC Plan The proposed ESC measures for the project will be further detailed in the contract plans. 8.2.2 Wet Season Construction If soils are exposed between October 1 and March 31,the contractor will mulch and seed as much disturbed area as possible by the first week of October to provide grass cover for the wet season.The contractor will also conform to the following wet season special provisions: 1. Apply cover measures to disturbed areas that are to remain unworked for more than 2 days. 2. Protect stockpiles that are to remain unworked for more than 12 hours. No area is to be left uncovered/denuded longer than 12 hours. 3. Provide onsite supplies of cover materials sufficient to cover all disturbed areas. 4. Seed all areas that are to be unworked during the wet season by the end of the first week of October. 5. Apply mulch to all seeded areas for protection. 6. Maintain a minimum of 50 linear feet of silt fence (and the necessary stakes) on site for every acre of disturbed area. 7. Provide construction road and parking lot stabilization areas for all sites, unless underlain by coarse grain soil. S. Provide sediment retention as required. 9. Provide additional surface water controls as required. 10. Implement construction phasing and more conservative BMPs for construction activity near surface waters(to be evaluated by contractor). 11. Runoff generated from dewatering activities is to be treated using suitable methods for the site. Review and maintain ESC measures on a weekly basis and within 24 hours after any runoff-producing event. 8.2.3 Construction in Sensitive Areas and Buffers Construction for this project will not be located within a stream buffer, a wetland or associated buffer, or within 50 feet of a lake. 8.2.4 Maintenance Requirements All ESC measures will be inspected and maintained on a regular basis following the maintenance requirements listed for each BMP, as described in KCSWDM Erosion and Sediment Control Standards Appendix D.The contractor will designate a certified ESC Supervisor and will give his or her name, address, and phone number to the City before construction begins. The ESC Supervisor will inspect the site at least once a month during the dry season,weekly during the wet season,and within 24 hours of each runoff-producing storm. If the City of Renton requires a written record of maintenance activities, a standard ESC maintenance report will be used as a written record of all maintenance. 8.2.5 Final Stabilization Before obtaining final construction approval,the following conditions must be met: 1. All disturbed areas of the site should be vegetated or otherwise permanently stabilized.At a minimum, disturbed areas will be seeded and mulched to provide a high likelihood that sufficient cover will 8_2 WBG103114153300SEA SECTION 8 ESC ANALYSIS AND DESIGN develop shortly after final approval. If seeded during the dry season,the seeded area will be irrigated as necessary to maintain the sprouted vegetation until the start of the wet season. 2. Structural measures such as silt fences, pipe slope drains, construction entrances, and storm drain inlet protection will be removed. 3. All permanent surface water facilities including catch basins, manholes, pipes, ditches, and channels will be cleaned. 8.2.6 Roads and Utilities Due to the limited right-of-way along the project,the contractor may propose other measures to better fit project conditions and provide reasonable protection.These measures may include alternative and experimental measures. WBG103114153300SEA 8-3 SECTION 9 Bond Quantities, Facility Summaries, and Declaration of Covenant 9.1 Bond Quantities This is a Public Works project,therefore this section does not apply. 9.2 Facility Summaries This is a Public Works project,therefore this section does not apply. 9.3 Declaration of Covenant This is a Public Works project to be owned and operated by the City of Renton.Therefore, a Declaration of Covenant is not required. WBG103114153300SEA 9-1 SECTION 10 Operations and Maintenance Manual An operations and maintenance manual is not required for flow control and water quality facilities, because this is a Public Works project and the City will assume maintenance and operation of systems. W BG 103114153 300SEA 10-1 SECTION it References American Society for Testing and Materials (ASTM). 2007. Method D422,Standard Test Method for Particle- Size Analysis of Soils(ASTM, 2007).American Society for Testing and Materials (ASTM). CH2M HILL. 2011.Sunset Area Surface Water Master Plan. Prepared for the City of Renton,Washington. April. CH2M HILL. 2012a.Sunset Stormwater Retrofit Low-Impact Development Project Geotechnical Data and Recommendations Report. Prepared for the City of Renton, Washington.August. CH2M HILL. 2012b.Sunset Area Low-Impact Development Retrofit Improvements Pre-Design Report. Prepared for the City of Renton, Washington. December. City of Renton. 2010a. Draft Sunset Area Community Planned Action NEPA/SEPA Environmental Impact Statement. Prepared for City of Renton and Renton Housing Authority. http://rentonwa.gov/uploadedFiles/Business/CED/planning/201O/Voll SunsetArea-PA DraftEIS.pdf. City of Renton Community and Economic Development, Renton, Washington. December. City of Renton. 2010b.Amendments to King County Surface Water Design Manual. httP://rentonwa.gov/uploadedFiles/Government/PW/UTILITIES/Surface Water/City%20Amendments%20to %20the%20King%20County%20Surface%20Water%20Design%20Manual.pdf. City of Renton, Public Works Department, Surface Water Utility, Washington. February. King County Department of Natural Resources. 2009. King County, Washington Surface Water Design Manual. Rusciano, G.M., C.C. Obropta. 2007. "Bioretention Column Study: Fecal Coliform and Total Suspended Solids Reductions."American Society of Agricultural and Biological Engineers 50(4). United States Department of Agriculture(USDA). 2013.Soil Survey, Natural Resources Conservation Service, Web Soil Survey. http://websoilsurvey.nres.usda.gov/. December. Washington State Department of Ecology(Ecology). 2012. Western Washington Hydrology Model. Version 4.0. http://www.ecy.wa.gov/programs/wq/stormwater/wwhmtraining. Washington Department of Ecology, Olympia, Washington. Washington State Department of Ecology(Ecology). 2014.Stormwater Management Manual for Western Washington. http://www.ecy.wa.gov/programs/wq/stormwater/manual.html.Washington Department of Ecology,Olympia, Washington.Amended December 2014. WBG103114153300SEA I I-1 Appendix A TI R Worksheet King County Department of Development and Environmental Services TECHNICAL INFORMATION REPORT (TIR) WORKSHEET Part 1 PROJECT OWNER AND Part 2 PROJECT LOCATION AND PROJECT ENGINEER DESCRIPTION Project Owner Project Name City of Renton Sunset Terrace Regional Stormwater Facility Address Renton City Hall, 1055 S Grady Way, Location WA 98057 Township 23N Phone (425)430-6500 Range 5E Project Engineer Raymond Chung,PE Sections 09 Company CH2M Hill Address/Phone 425 233-3567 Part 3 TYPE OF PERMIT Part 4 OTHER REVIEWS AND PERMITS APPLICATION Subdivison DFW HPA Shoreline Management Short Subdivision COE 404 Rockery Grading DOE Dam Safety Structural Vaults _ FEMA Floodplain Other—Biological Commercial COE Wetlands Assessment Other- Regional Stormwater Facility NPDES Part 5 SITE COMMUNITY AND DRAINAGE BASIN Community City of Renton, WA Drainage Basin John's Creek Basin Part 6 SITE CHARACTERISTICS River None Floodplain None Stream None Wetlands None Critical Stream Reach None Seeps/Springs None Depressions/Swales None Lake None High Groundwater Table None Steep Slopes None Groundwater Recharge None Other Figure 1-1 Part 7 SOILS Soil Type Slopes Erosion Potential Erosive Velocities Pavement 0—5% None Ragner-Indianola Up to 3:1 Cut/Fill Low Urban Up to 3:1 Cut/Fill Low Arents, Alderwood Up to 3:1 Cut/Fill Low See Figure 1-2 Part 8 DEVELOPMENT LIMITATIONS REFERENCE LIMITATION/SITE CONSTRAINT Part 9 ESC REQUIREMENTS MINIMUM ESC REQUIREMENTS MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION AFTER CONSTRUCTION ♦ Sedimentation Facilities ♦ Stabilize Exposed Surface ♦ Stabilized Construction Entrance ♦ Remove and Restore Temporary ESC Facilities ♦ Perimeter Runoff Control ♦ Clean and Remove All Silt and Debris ♦ Clearing and Grading Restrictions ♦ Ensure Operation of Permanent Facilities ♦ Cover Practices ♦ Flag Limits of SAO and open space ♦ Construction Sequence preservation Other Other Figure 1-1 Part 10 SURFACE WATER SYSTEM ❑ Grass Lined [ Tank Infiltration Method of Analysis Channel ❑ Depression Pipes- Rational Pipe System ❑ Vault Method ❑ Flow Dispersal ❑ Open Channel ❑ Energy Dissipater El Waiver Treatment-WWHM ❑ Dry Pond ❑ Wetland ❑ Regional ❑ Wet Pond ❑ Stream Detention �l Bioretention Brief Description of System Operation: Stormwater runoff off of roadway pavement will be collected by catch basins and directed into two bioretention cells with an underlying infiltration gallery for water quality treatment. A treatment layer will be installed underneath the infiltration gallery. Facility Related Site Limitations Reference Facility Limitation Part 11 STRUCTURAL ANALYSIS Part 12 EASEMENTS/TRACTS ❑ Cast in Place Vault Drainage Easement(Existing) ❑i Retaining Wall ❑ Access Easement Rockery> 4' High ❑ Native Growth Protection Easement ❑ Structural on Steep Slope ❑ Tract ❑ Other- ❑ Other Part 13 SIGNATURE OF PROFESSIONAL ENGINEER I or a civil engineer under my supervision have visited the site. Actual site conditions as observed were incorporated into this worksheet and the attachments. To the best of my knowledge the information provided here is accurate. Raymond Chung, P.E./January 20, 2015 Signed/Date Figure 1-1 Appendix B Facility Hydrological Analysis (WWHM) WWHM4 PROJECT REPORT General Model Information Project Name: 1.5in-hr with underdrain_ELT_1-26-15 Site Name: Sunset Site Address: City: Renton Report Date: 1/27/2015 Gage: Seatac Data Start: 1948/10/01 Data End: 1998/09/30 Timestep: Hourly Precip Scale: 0.00 (adjusted) Version: 2013/04/29 POC Thresholds Low Flow Threshold for POC1: 50 Percent of the 2 Year High Flow Threshold for POC1: 50 Year 1.5in-hrwith underdrain_ELT_1-26-15 1/27/2015 3:16:11 PM Page 2 Landuse Basin Data Predeveloped Land Use Basin 1 Bypass: No GroundWater: No Pervious Land Use Acres A B, Lawn, Flat 3.77 C, Lawn, Flat 3.76 Pervious Total 7.53 Impervious Land Use Acres Impervious Total 0 Basin Total 7.53 Element Flows To: Surface Interflow Groundwater 1.5in-hr with underdrain ELT 1-26-15 1/27/2015 3:16:11 PM Page 3 Mitigated Land Use SUNSETBLVD Bypass: No GroundWater: No Pervious Land Use Acres Pervious Total 0 Impervious Land Use Acres ROADS FLAT 2.03 Impervious Total 2.03 Basin Total 2.03 Element Flows To: Surface Interflow Groundwater Flow Splitter 1 Flow Splitter 1 1.5in-hr with underdrain_ELT_1-26-15 1/27/2015 3:16:11 PM Page 4 Basin 2 Bypass: No GroundWater: No Pervious Land Use Acres Pervious Total 0 Impervious Land Use Acres PARKING FLAT 5.4 Impervious Total 5.4 Basin Total 5.4 Element Flows To: Surface Interflow Groundwater Flow Splitter 1 Flow Splitter 1 1.5in-hr with underdrain ELT 1-26-15 1/27/2015 3:16:11 PM Page 5 Basin 3 Bypass: No GroundWater: No Pervious Land Use Acres Pervious Total 0 Impervious Land Use Acres ROADS FLAT 0.1 Impervious Total 0.1 Basin Total 0.1 Element Flows To: Surface Interflow Groundwater Surface Bio Swale 1 Surface Bio Swale 1 1.5in-hr with underdrain_ELT_1-26-15 1/27/2015 3:16:11 PM Page 6 Routing Elements Predeveloped Routing 1.5in-hr with underdrain_ELT_1-26-15 1/27/2015 3:16:11 PM Page 7 Mitigated Routing Infiltration Bed Bottom Length: 150.00 ft. Bottom Width: 70.00 ft. 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: 0.3 Material thickness of second layer: 0 Pour Space of material for second layer: 0 Material thickness of third layer: 0 Pour Space of material for third layer: 0 Infiltration On Infiltration rate: 1.2 Infiltration safety factor: 1 Discharge Structure Riser Height: 2.42 ft. Riser Diameter: 1.5 in. Element Flows To: Outlet 1 Outlet 2 Gravel Trench Bed Hydraulic Table Stage(ft) Area(ac) Volume(ac-ft) Discharge(cfs) Infilt(cfs) 0.0000 0.241 0.000 0.000 0.000 0.0444 0.241 0.003 0.000 0.291 0.0889 0.241 0.006 0.000 0.291 0.1333 0.241 0.009 0.000 0.291 0.1778 0.241 0.012 0.000 0.291 0.2222 0.241 0.016 0.000 0.291 0.2667 0.241 0.019 0.000 0.291 0.3111 0.241 0.022 0.000 0.291 0.3556 0.241 0.025 0.000 0.291 0.4000 0.241 0.028 0.000 0.291 0.4444 0.241 0.032 0.000 0.291 0.4889 0.241 0.035 0.000 0.291 0.5333 0.241 0.038 0.000 0.291 0.5778 0.241 0.041 0.000 0.291 0.6222 0.241 0.045 0.000 0.291 0.6667 0.241 0.048 0.000 0.291 0.7111 0.241 0.051 0.000 0.291 0.7556 0.241 0.054 0.000 0.291 0.8000 0.241 0.057 0.000 0.291 0.8444 0.241 0.061 0.000 0.291 0.8889 0.241 0.064 0.000 0.291 0.9333 0.241 0.067 0.000 0.291 0.9778 0.241 0.070 0.000 0.291 1.0222 0.241 0.074 0.000 0.291 1.0667 0.241 0.077 0.000 0.291 1.1111 0.241 0.080 0.000 0.291 1.1556 0.241 0.083 0.000 0.291 1.2000 0.241 0.086 0.000 0.291 1.2444 0.241 0.090 0.000 0.291 1.2889 0.242 0.093 0.000 0.291 1.5in-hrwith underdrain ELT 1-26-15 1/27/2015 3:16:11 PM 1.3333 0.242 0.096 0.000 0.291 1.3778 0.242 0.099 0.000 0.291 1.4222 0.242 0.103 0.000 0.291 1.4667 0.242 0.106 0.000 0.291 1.5111 0.242 0.109 0.000 0.291 1.5556 0.242 0.112 0.000 0.291 1.6000 0.242 0.116 0.000 0.291 1.6444 0.242 0.119 0.000 0.291 1.6889 0.242 0.122 0.000 0.291 1.7333 0.242 0.125 0.000 0.291 1.7778 0.242 0.128 0.000 0.291 1 .8222 0.242 0.132 0.000 0.291 1 .8667 0.242 0.135 0.000 0.291 1.9111 0.242 0.138 0.000 0.291 1.9556 0.242 0.141 0.000 0.291 2.0000 0.242 0.145 0.000 0.291 2.0444 0.242 0.148 0.000 0.291 2.0889 0.242 0.151 0.000 0.291 2.1333 0.242 0.154 0.000 0.291 2.1778 0.242 0.158 0.000 0.291 2.2222 0.242 0.161 0.000 0.291 2.2667 0.242 0.164 0.000 0.291 2.3111 0.242 0.167 0.000 0.291 2.3556 0.242 0.170 0.000 0.291 2.4000 0.242 0.174 0.000 0.291 2.4444 0.242 0.177 0.004 0.291 2.4889 0.242 0.180 0.022 0.291 2.5333 0.242 0.183 0.046 0.291 2.5778 0.242 0.187 0.076 0.291 2.6222 0.242 0.190 0.110 0.291 2.6667 0.242 0.193 0.149 0.291 2.7111 0.243 0.196 0.191 0.291 2.7556 0.243 0.200 0.236 0.291 2.8000 0.243 0.203 0.285 0.291 2.8444 0.243 0.206 0.336 0.291 2.8889 0.243 0.209 0.390 0.291 2.9333 0.243 0.213 0.447 0.291 2.9778 0.243 0.216 0.507 0.291 3.0222 0.243 0.227 0.568 0.291 3.0667 0.243 0.237 0.633 0.291 3.1111 0.243 0.248 0.699 0.291 3.1556 0.243 0.259 0.768 0.291 3.2000 0.243 0.270 0.838 0.291 3.2444 0.243 0.281 0.911 0.291 3.2889 0.243 0.292 0.986 0.291 3.3333 0.243 0.302 1.062 0.291 3.3778 0.243 0.313 1.141 0.291 3.4222 0.243 0.324 1.221 0.291 3.4667 0.243 0.335 1.303 0.291 3.5111 0.243 0.346 1.387 0.291 3.5556 0.243 0.356 1.473 0.291 3.6000 0.243 0.367 1.560 0.291 3.6444 0.243 0.378 1.649 0.291 3.6889 0.243 0.389 1.740 0.291 3.7333 0.243 0.400 1.832 0.291 3.7778 0.243 0.411 1.926 0.291 3.8222 0.243 0.421 2.021 0.291 3.8667 0.243 0.432 2.118 0.291 1.5in-hr with underdrain ELT 1-26-15 1/27/2015 3:16:11 PM 3.9111 0.243 0.443 2.216 0.291 3.9556 0.243 0.454 2.316 0.291 4.0000 0.243 0.465 2.417 0.291 1.5in-hr with underdrain_ELT_1-26-15 1/27/2015 3:16:11 PM Page 10 Flow Splitter 1 Bottom Length: 5.00 ft. Bottom Length: 5.00 ft. Depth: 5 ft. Side slope 1: 0 To 1 Side slope 2: 0 To 1 Side slope 3: 0 To 1 Side slope 4: 0 To 1 Control Structure Splitter Hydraulic Table Stage(ft) Area(ac) Volume(ac-ft) Primary(cfs) Secondary(cfs) 337.0 0.000 0.000 0.000 0.000 337.0 0.000 0.000 0.261 0.000 337.1 0.000 0.000 0.369 0.400 337.1 0.000 0.000 0.453 0.668 337.2 0.000 0.000 0.523 0.856 337.2 0.000 0.000 0.584 1.010 337.3 0.000 0.000 0.640 1.143 337.3 0.000 0.000 0.801 1.423 337.4 0.000 0.000 0.956 1.646 337.5 0.000 0.000 1.071 1.825 337.5 0.000 0.000 1.169 1.984 337.6 0.000 0.000 1.257 2.129 337.6 0.000 0.000 1.338 2.263 337.7 0.000 0.000 1.414 2.389 337.7 0.000 0.000 1.486 2.508 337.8 0.000 0.000 1.553 2.622 337.8 0.000 0.000 1.618 2.730 337.9 0.000 0.000 1.680 2.834 338.0 0.000 0.000 1.740 2.935 338.0 0.000 0.000 1.797 3.032 338.1 0.000 0.000 1.853 3.126 338.1 0.000 0.000 1.907 3.217 338.2 0.000 0.000 1.960 3.305 338.2 0.000 0.000 2.011 3.391 338.3 0.000 0.000 2.061 3.475 338.3 0.000 0.000 2.109 3.557 338.4 0.000 0.000 2.157 3.638 338.5 0.000 0.000 2.203 3.716 338.5 0.000 0.000 2.249 3.793 338.6 0.000 0.000 2.293 3.868 338.6 0.000 0.001 2.337 3.942 338.7 0.000 0.001 2.380 4.014 338.7 0.000 0.001 2.422 4.085 338.8 0.000 0.001 2.463 4.155 338.8 0.000 0.001 2.504 4.224 338.9 0.000 0.001 2.544 4.347 339.0 0.000 0.001 2.583 4.689 339.0 0.000 0.001 2.622 5.153 339.1 0.000 0.001 2.660 5.709 339.1 0.000 0.001 2.698 6.341 339.2 0.000 0.001 2.767 7.042 339.2 0.000 0.001 2.983 7.803 339.3 0.000 0.001 3.282 8.620 339.3 0.000 0.001 3.643 9.488 339.4 0.000 0.001 4.056 10.40 339.5 0.000 0.001 4.514 11.37 339.5 0.000 0.001 5.013 12.37 1,5in-hrwith underdrain ELT 1-26-15 1/27/20153:16:11 PM 339.6 0.000 0.001 5.549 13.42 339.6 0.000 0.001 6.120 14.51 339.7 0.000 0.001 6.724 15.64 339.7 0.000 0.001 7.359 16.80 339.8 0.000 0.001 8.023 18.00 339.8 0.000 0.001 8.715 19.24 339.9 0.000 0.001 9.434 20.51 340.0 0.000 0.001 10.17 21.81 340.0 0.000 0.001 10.94 23.14 340.1 0.000 0.001 11.74 24.51 340.1 0.000 0.001 12.55 25.90 340.2 0.000 0.001 13.39 27.33 340.2 0.000 0.001 14.26 28.79 340.3 0.000 0.001 15.14 30.27 340.3 0.000 0.001 16.04 31.78 340.4 0.000 0.002 16.97 33.32 340.5 0.000 0.002 17.91 34.88 340.5 0.000 0.002 18.88 36.48 340.6 0.000 0.002 19.86 38.10 340.6 0.000 0.002 20.86 39.74 340.7 0.000 0.002 21.88 41.41 340.7 0.000 0.002 22.92 43.10 340.8 0.000 0.002 23.98 44.82 340.8 0.000 0.002 25.05 46.56 340.9 0.000 0.002 26.14 48.33 341.0 0.000 0.002 27.25 50.12 341.0 0.000 0.002 28.37 51.93 341.1 0.000 0.002 29.51 53.77 341.1 0.000 0.002 30.67 55.63 341.2 0.000 0.002 31.84 57.51 341.2 0.000 0.002 33.03 59.41 341.3 0.000 0.002 34.23 61.33 341.3 0.000 0.002 35.45 63.28 341.4 0.000 0.002 36.69 65.25 341.5 0.000 0.002 37.93 67.23 341.5 0.000 0.002 39.20 69.24 341.6 0.000 0.002 40.48 71.27 341.6 0.000 0.002 41.77 73.32 341.7 0.000 0.002 43.08 75.39 341.7 0.000 0.002 44.40 77.48 341.8 0.000 0.002 45.73 79.59 341.8 0.000 0.002 47.08 81.72 341.9 0.000 0.002 48.44 83.87 342.0 0.000 0.002 49.82 86.04 342.0 0.000 0.002 51.21 88.22 Discharge Structure Riser Height: 2.2 ft. Riser Diameter: 12 in. Orifice 1 Diameter: 6.5 in. Elevation:0 ft. Orifice 2 Diameter: 5.5 in. Elevation:0.37 ft. Element Flows To: Outlet 1 Outlet 2 Surface Bio Swale 1 Channel 1 1.5in-hrwith underdrain ELT 1-26-15 1/27/20153:16:11 PM Page 12 Channel 1 Bottom Length: 6.00 ft. Bottom Width: 3.00 ft. Manning's n: 0.03 Channel bottom slope 1: 0.05 To 1 Channel Left side slope 0: 4 To 1 Channel right side slope 2: 4 To 1 Discharge Structure Riser Height: 0 ft. Riser Diameter: 0 in. Element Flows To: Outlet 1 Outlet 2 Channel Hydraulic Table Stage(ft) Area(ac) Volume(ac-ft) Discharge(cfs) Infilt(cfs) 0.0000 0.000 0.000 0.000 0.000 0.0222 0.000 0.000 0.059 0.000 0.0444 0.000 0.000 0.189 0.000 0.0667 0.000 0.000 0.376 0.000 0.0889 0.000 0.000 0.614 0.000 0.1111 0.000 0.000 0.901 0.000 0.1333 0.000 0.000 1.236 0.000 0.1556 0.000 0.000 1.618 0.000 0.1778 0.000 0.000 2.047 0.000 0.2000 0.000 0.000 2.523 0.000 0.2222 0.000 0.000 3.046 0.000 0.2444 0.000 0.000 3.617 0.000 0.2667 0.000 0.000 4.235 0.000 0.2889 0.000 0.000 4.903 0.000 0.3111 0.000 0.000 5.620 0.000 0.3333 0.000 0.000 6.387 0.000 0.3556 0.000 0.000 7.205 0.000 0.3778 0.000 0.000 8.075 0.000 0.4000 0.000 0.000 8.996 0.000 0.4222 0.000 0.000 9.971 0.000 0.4444 0.000 0.000 11.00 0.000 0.4667 0.000 0.000 12.08 0.000 0.4889 0.001 0.000 13.22 0.000 0.5111 0.001 0.000 14.42 0.000 0.5333 0.001 0.000 15.67 0.000 0.5556 0.001 0.000 16.98 0.000 0.5778 0.001 0.000 18.35 0.000 0.6000 0.001 0.000 19.78 0.000 0.6222 0.001 0.000 21.27 0.000 0.6444 0.001 0.000 22.82 0.000 0.6667 0.001 0.000 24.43 0.000 0.6889 0.001 0.000 26.11 0.000 0.7111 0.001 0.000 27.85 0.000 0.7333 0.001 0.000 29.66 0.000 0.7556 0.001 0.000 31.53 0.000 0.7778 0.001 0.000 33.47 0.000 0.8000 0.001 0.000 35.47 0.000 0.8222 0.001 0.000 37.54 0.000 0.8444 0.001 0.000 39.69 0.000 0.8667 0.001 0.000 41.90 0.000 1.5in-hr with underdrain ELT 1-26-15 1/27/2015 3:16:11 PM Page 13 0.8889 0.001 0.000 44.18 0.000 0.9111 0.001 0.000 46.53 0.000 0.9333 0.001 0.000 48.95 0.000 0.9556 0.001 0.000 51.45 0.000 0.9778 0.001 0.000 54.02 0.000 1.0000 0.001 0.001 56.67 0.000 1.0222 0.001 0.001 59.39 0.000 1.0444 0.001 0.001 62.19 0.000 1.0667 0.001 0.001 65.06 0.000 1.0889 0.001 0.001 68.01 0.000 1.1111 0.001 0.001 71.04 0.000 1.1333 0.001 0.001 74.15 0.000 1.1556 0.001 0.001 77.33 0.000 1.1778 0.001 0.001 80.60 0.000 1.2000 0.001 0.001 83.95 0.000 1.2222 0.001 0.001 87.38 0.000 1.2444 0.001 0.001 90.90 0.000 1.2667 0.001 0.001 94.50 0.000 1.2889 0.001 0.001 98.18 0.000 1.3111 0.001 0.001 101.9 0.000 1.3333 0.001 0.001 105.8 0.000 1.3556 0.002 0.001 109.7 0.000 1.3778 0.002 0.001 113.7 0.000 1.4000 0.002 0.001 117.8 0.000 1.4222 0.002 0.001 122.0 0.000 1.4444 0.002 0.001 126.3 0.000 1.4667 0.002 0.001 130.7 0.000 1.4889 0.002 0.001 135.2 0.000 1.5111 0.002 0.001 139.8 0.000 1.5333 0.002 0.002 144.4 0.000 1.5556 0.002 0.002 149.2 0.000 1.5778 0.002 0.002 154.0 0.000 1.6000 0.002 0.002 159.0 0.000 1.6222 0.002 0.002 164.0 0.000 1.6444 0.002 0.002 169.1 0.000 1.6667 0.002 0.002 174.3 0.000 1.6889 0.002 0.002 179.7 0.000 1.7111 0.002 0.002 185.1 0.000 1.7333 0.002 0.002 190.6 0.000 1.7556 0.002 0.002 196.2 0.000 1 .7778 0.002 0.002 202.0 0.000 1.8000 0.002 0.002 207.8 0.000 1.8222 0.002 0.002 213.7 0.000 1.8444 0.002 0.002 219.7 0.000 1.8667 0.002 0.002 225.9 0.000 1.8889 0.002 0.002 232.1 0.000 1.9111 0.002 0.002 238.4 0.000 1.9333 0.002 0.002 244.9 0.000 1.9556 0.002 0.003 251.4 0.000 1.9778 0.002 0.003 258.1 0.000 2.0000 0.002 0.003 264.8 0.000 2.0222 0.002 0.003 271.7 0.000 1.5in-hr with underdrain_ELT_1-26-15 1/27/2015 3:16:11 PM Page 14 Bio Swale 1 Bottom Length: 150.00 ft. Bottom Width: 9.00 ft. Material thickness of first layer: 1.5 Material type for first layer: Amended 1.5 in/hr Material thickness of second layer: 3 Material type for second layer: GRAVEL Material thickness of third layer: 0 Material type for third layer: GRAVEL Underdrain used Underdrain Diameter (ft): 1 Orifice Diameter (in): 12 Offset (in): 0 Flow Through Underdrain (ac-ft): 501.96 Total Outflow (ac-ft): 691.064 Percent Through Underdrain: 72.64 Discharge Structure Riser Height: 0.5 ft. Riser Diameter: 48 in. Element Flows To: Outlet 1 Outlet 2 Infiltration Bed Landscape Swale Hydraulic Table Stage(ft) Area(ac) Volume(ac-ft) Discharge(cfs) Infilt(cfs) 0.0000 0.1463 0.0000 0.0000 0.0000 0.0659 0.1458 0.0008 0.0000 0.0000 0.1319 0.1439 0.0016 0.0000 0.0000 0.1978 0.1419 0.0024 0.0000 0.0000 0.2637 0.1400 0.0033 0.0000 0.0000 0.3297 0.1381 0.0042 0.0000 0.0000 0.3956 0.1362 0.0051 0.0000 0.0022 0.4615 0.1343 0.0061 0.0000 0.0022 0.5275 0.1324 0.0071 0.1774 0.0029 0.5934 0.1306 0.0081 1.1121 0.0038 0.6593 0.1287 0.0092 2.4778 0.0050 0.7253 0.1268 0.0103 4.1653 0.0065 0.7912 0.1250 0.0115 6.1218 0.0083 0.8571 0.1231 0.0127 8.3145 0.0090 0.9231 0.1213 0.0139 10.720 0.0104 0.9890 0.1194 0.0152 13.321 0.0128 1.0549 0.1176 0.0165 16.105 0.0155 1.1209 0.1158 0.0178 19.058 0.0185 1.1868 0.1140 0.0192 22.173 0.0219 1.2527 0.1122 0.0206 25.442 0.0221 1.3187 0.1104 0.0221 28.857 0.0257 1.3846 0.1086 0.0236 32.412 0.0299 1.4505 0.1068 0.0251 36.102 0.0344 1.5165 0.1050 0.0269 39.923 0.0393 1.5824 0.1032 0.0287 43.870 0.0427 1.6484 0.1015 0.0306 47.939 0.0447 1.7143 0.0997 0.0325 52.126 0.0504 1.7802 0.0980 0.0345 56.429 0.0566 1.8462 0.0962 0.0365 60.844 0.0615 1.9121 0.0945 0.0386 65.368 0.0615 1.9780 0.0928 0.0407 70.000 0.0615 1.5in-hr with underdrain ELT 1-26-15 1/27/20153:16:11 PM 2.0440 0.0911 0.0428 74.735 0.0615 2.1099 0.0893 0.0450 79.574 0.0615 2.1758 0.0876 0.0472 84.512 0.0615 2.2418 0.0859 0.0495 89.548 0.0615 2.3077 0.0842 0.0518 94.681 0.0615 2.3736 0.0826 0.0542 99.9076 0.0615 2.4396 0.0809 0.0566 105.23 0.0615 2.5055 0.0792 0.0591 110.64 0.0615 2.5714 0.0775 0.0616 116.14 0.0615 2.6374 0.0759 0.0642 121.73 0.0615 2.7033 0.0742 0.0668 127.40 0.0615 2.7692 0.0726 0.0695 133.17 0.0615 2.8352 0.0710 0.0722 139.01 0.0615 2.9011 0.0693 0.0749 144.94 0.0615 2.9670 0.0677 0.0777 150.95 0.0615 3.0330 0.0661 0.0806 157.04 0.0615 3.0989 0.0645 0.0835 163.21 0.0615 3.1648 0.0629 0.0864 169.46 0.0615 3.2308 0.0613 0.0894 175.79 0.0615 3.2967 0.0597 0.0924 182.20 0.0615 3.3626 0.0581 0.0955 188.68 0.0615 3.4286 0.0566 0.0987 195.24 0.0615 3.4945 0.0550 0.1019 201.87 0.0615 3.5604 0.0535 0.1051 208.57 0.0615 3.6264 0.0519 0.1084 215.35 0.0615 3.6923 0.0504 0.1118 222.19 0.0615 3.7582 0.0488 0.1152 229.11 0.0615 3.8242 0.0473 0.1186 236.10 0.0615 3.8901 0.0458 0.1221 243.16 0.0615 3.9560 0.0443 0.1256 250.29 0.0615 4.0220 0.0428 0.1292 257.49 0.0615 4.0879 0.0413 0.1329 264.75 0.0615 4.1538 0.0398 0.1366 272.08 0.0615 4.2198 0.0383 0.1403 279.48 0.0615 4.2857 0.0368 0.1441 286.94 0.0615 4.3516 0.0354 0.1480 294.47 0.0615 4.4176 0.0339 0.1519 302.07 0.0615 4.4835 0.0324 0.1559 309.72 0.0615 4.5000 0.0310 0.1569 317.45 0.0615 Landscape Swale Hydraulic Table Stag e(ft)Area(ac)VoIume(ac-ft)Discharge(cfs)To Amended()cfs)Infilt(cfs) 4.5000 0.0310 0.1569 0.0000 0.0642 0.037 4.5659 0.1482 0.1666 0.0000 0.0642 0.037 4.6319 0.1502 0.1764 0.0000 0.0669 0.037 4.6978 0.1521 0.1864 0.0000 0.0696 0.037 4.7637 0.1541 0.1965 0.0000 0.0723 0.037 4.8297 0.1560 0.2067 0.0000 0.0750 0.037 4.8956 0.1580 0.2171 0.0000 0.0777 0.037 4.9615 0.1600 0.2275 0.0000 0.0804 0.037 5.0275 0.1620 0.2382 0.1774 0.0831 0.037 5.0934 0.1640 0.2489 1.1121 0.0859 0.037 5.1593 0.1660 0.2598 2.4778 0.0886 0.037 5.2253 0.1680 0.2708 4.1653 0.0913 0.037 5.2912 0.1700 0.2819 6.1218 0.0940 0.037 5.3571 0.1720 0.2932 8.3145 0.0967 0.037 5.4231 0.1741 0.3046 10.720 0.0994 0.037 5.4890 0.1761 0.3162 13.321 0.1021 0.037 1.5in-hr with underdrain_ELT_1-26-15 1/27/2015 3:16:11 PM Page 16 5.5549 0.1782 0.3278 16.105 0.1048 0.037 5.6209 0.1802 0.3397 19.058 0.1075 0.037 5.6868 0.1823 0.3516 22.173 0.1102 0.037 5.7527 0.1843 0.3637 25.442 0.1129 0.037 5.8187 0.1864 0.3759 28.857 0.1156 0.037 5.8846 0.1885 0.3883 32.412 0.1183 0.037 5.9505 0.1906 0.4008 36.102 0.1210 0.037 6.0000 0.1921 0.4102 39.923 0.1230 0.000 1.5in-hr with underdrain ELT 1-26-15 1/27/2015 3:16:11 PM Page 17 Surface Bio Swale 1 Element Flows To: Outlet 1 Outlet 2 Infiltration Bed Bio Swale 1 1.5in-hr with underdrain_ELT_1-26-15 1/27/2015 3:16:11 PM Page 18 Analysis Results POC 1 0.110EA 10E-3 10E-2 10E-1 1 10 100 om aa+ P�ro�nt Timo Exceed•np OS , 7 6 10 ]0 M 50 10 80 YO 06 BB W 606 1 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area: 7.53 Total Impervious Area: 0 Mitigated Landuse Totals for POC #1 Total Pervious Area: 0 Total Impervious Area: 7.53 Flow Frequency Method: Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.200281 5 year 0.338011 10 year 0.452123 25 year 0.624842 50 year 0.77583 100 year 0.947327 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.065746 5 year 0.126123 10 year 0.168033 25 year 0.219699 50 year 0.256165 100 year 0.290459 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1949 0.235 0.000 1950 0.993 0.000 1951 0.436 0.251 1952 0.147 0.000 1953 0.103 0.000 1954 0.188 0.000 1955 0.266 0.156 1956 0.301 0.000 1957 0.262 0.030 1958 0.165 0.000 1.5in-hr with underdrain ELT 1-26-15 1/27/2015 3:16:11 PM Page 19 1959 0.169 0.000 1960 0.283 0.260 1961 0.232 0.000 1962 0.093 0.000 1963 0.176 0.000 1964 0.201 0.000 1965 0.135 0.000 1966 0.156 0.000 1967 0.365 0.059 1968 0.205 0.000 1969 0.161 0.000 1970 0.166 0.000 1971 0.178 0.000 1972 0.568 0.143 1973 0.138 0.000 1974 0.183 0.000 1975 0.319 0.176 1976 0.178 0.000 1977 0.067 0.000 1978 0.194 0.000 1979 0.084 0.000 1980 0.249 0.087 1981 0.213 0.000 1982 0.451 0.497 1983 0.180 0.000 1984 0.175 0.000 1985 0.094 0.000 1986 0.336 0.323 1987 0.297 0.367 1988 0.114 0.000 1989 0.081 0.000 1990 0.715 0.664 1991 0.559 0.567 1992 0.161 0.000 1993 0.126 0.000 1994 0.060 0.000 1995 0.174 0.000 1996 0.544 0.303 1997 0.378 0.294 1998 0.196 0.000 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.9928 0.6637 2 0.7153 0.5668 3 0.5683 0.4969 4 0.5591 0.3667 5 0.5436 0.3231 6 0.4508 0.3025 7 0.4357 0.2943 8 0.3778 0.2597 9 0.3649 0.2509 10 0.3357 0.1765 11 0.3190 0.1556 12 0.3006 0.1434 13 0.2968 0.0872 14 0.2826 0.0591 1.5in-hr with underdrain_ELT_1-26-15 1/27/2015 3:16:22 PM Page 20 15 0.2661 0.0303 16 0.2615 0.0000 17 0.2492 0.0000 18 0.2354 0.0000 19 0.2318 0.0000 20 0.2125 0.0000 21 0.2047 0.0000 22 0.2011 0.0000 23 0.1960 0.0000 24 0.1935 0.0000 25 0.1882 0.0000 26 0.1825 0.0000 27 0.1800 0.0000 28 0.1783 0.0000 29 0.1780 0.0000 30 0.1764 0.0000 31 0.1752 0.0000 32 0.1741 0.0000 33 0.1686 0.0000 34 0.1660 0.0000 35 0.1650 0.0000 36 0.1610 0.0000 37 0.1607 0.0000 38 0.1564 0.0000 39 0.1466 0.0000 40 0.1381 0.0000 41 0.1352 0.0000 42 0.1260 0.0000 43 0.1139 0.0000 44 0.1028 0.0000 45 0.0939 0.0000 46 0.0931 0.0000 47 0.0836 0.0000 48 0.0806 0.0000 49 0.0674 0.0000 50 0.0605 0.0000 1.5in-hrwith underdrain ELT 1-26-15 1/27/2015 3:16:22 PM Page 21 Duration Flows The Facility PASSED Flow(cfs) Predev Mit Percentage Pass/Fail 0.1001 2064 81 3 Pass 0.1070 1746 80 4 Pass 0.1138 1493 78 5 Pass 0.1206 1243 72 5 Pass 0.1274 1066 70 6 Pass 0.1343 912 67 7 Pass 0.1411 791 65 8 Pass 0.1479 697 64 9 Pass 0.1547 607 63 10 Pass 0.1616 509 60 11 Pass 0.1684 437 58 13 Pass 0.1752 387 55 14 Pass 0.1820 337 47 13 Pass 0.1889 307 43 14 Pass 0.1957 267 42 15 Pass 0.2025 241 40 16 Pass 0.2093 219 39 17 Pass 0.2162 178 38 21 Pass 0.2230 154 38 24 Pass 0.2298 135 37 27 Pass 0.2366 116 32 27 Pass 0.2435 105 30 28 Pass 0.2503 93 30 32 Pass 0.2571 86 26 30 Pass 0.2639 75 24 32 Pass 0.2708 67 23 34 Pass 0.2776 63 21 33 Pass 0.2844 58 20 34 Pass 0.2912 53 20 37 Pass 0.2981 46 18 39 Pass 0.3049 39 15 38 Pass 0.3117 38 14 36 Pass 0.3185 37 14 37 Pass 0.3254 35 12 34 Pass 0.3322 35 10 28 Pass 0.3390 33 10 30 Pass 0.3458 33 10 30 Pass 0.3527 32 10 31 Pass 0.3595 30 10 33 Pass 0.3663 26 8 30 Pass 0.3731 23 7 30 Pass 0.3800 18 7 38 Pass 0.3868 16 7 43 Pass 0.3936 16 7 43 Pass 0.4004 16 7 43 Pass 0.4073 16 7 43 Pass 0.4141 16 7 43 Pass 0.4209 16 6 37 Pass 0.4277 15 6 40 Pass 0.4346 15 6 40 Pass 0.4414 12 6 50 Pass 0.4482 11 6 54 Pass 0.4550 10 6 60 Pass 1.5in-hr with underdrain_ELT_1-26-15 1/27/2015 3:16.22 PM Page 22 0.4619 10 6 60 Pass 0.4687 9 5 55 Pass 0.4755 9 5 55 Pass 0.4823 9 5 55 Pass 0.4892 9 5 55 Pass 0.4960 9 5 55 Pass 0.5028 8 4 50 Pass 0.5096 8 4 50 Pass 0.5165 8 4 50 Pass 0.5233 8 4 50 Pass 0.5301 8 4 50 Pass 0.5369 8 4 50 Pass 0.5438 8 4 50 Pass 0.5506 7 4 57 Pass 0.5574 7 4 57 Pass 0.5643 6 4 66 Pass 0.5711 5 3 60 Pass 0.5779 5 3 60 Pass 0.5847 5 3 60 Pass 0.5916 5 3 60 Pass 0.5984 5 3 60 Pass 0.6052 5 2 40 Pass 0.6120 5 1 20 Pass 0.6189 5 1 20 Pass 0.6257 5 1 20 Pass 0.6325 5 1 20 Pass 0.6393 5 1 20 Pass 0.6462 5 1 20 Pass 0.6530 5 1 20 Pass 0.6598 5 1 20 Pass 0.6666 3 0 0 Pass 0.6735 3 0 0 Pass 0.6803 3 0 0 Pass 0.6871 3 0 0 Pass 0.6939 3 0 0 Pass 0.7008 3 0 0 Pass 0.7076 2 0 0 Pass 0.7144 2 0 0 Pass 0.7212 1 0 0 Pass 0.7281 1 0 0 Pass 0.7349 1 0 0 Pass 0.7417 1 0 0 Pass 0.7485 1 0 0 Pass 0.7554 1 0 0 Pass 0.7622 1 0 0 Pass 0.7690 1 0 0 Pass 0.7758 1 0 0 Pass 1.5in-hr with underdrain ELT 1-26-15 1/27/2015 3:16:22 PM Page 23 Water Quality Water Quality BMP Flow and Volume for POC #1 On-line facility volume: 0.3686 acre-feet On-line facility target flow: 0.3435 cfs. Adjusted for 15 min: 0.3881 cfs. Off-line facility target flow: 0.1908 cfs. Adjusted for 15 min: 0.2156 cfs. 1.5in-hr with underdrain_ELT_1-26-15 1/27/2015 3:16:22 PM Page 24 Model Default Modifications Total of 0 changes have been made. PERLND Changes No PERLND changes have been made. IMPLND Changes No IMPLND changes have been made. 1.5in-hrwith underdrain_ELT_1-26-15 1/27/2015 3:16:22 PM Page 25 Appendix Predeveloped Schematic Basin I 53ac 1.5in-hrwith underdrain ELT 1-26-15 1/27/2015 3:16:22 PM Page 26 Mitigated Schematic j Basin UNS Basin 3 SI SI Flow Splitter s I 1 I S Bio Svyale 1 hannel 1 S 1 nfiltrat on Bed 1.5in-hr with underdrain_ELT_1-26-15 1/27/2015 3:16:22 PM Page 27 Disclaimer Legal Notice This program and accompanying documentation are provided 'as-is' without warranty of any kind. The, entire risk regarding the performance and results of this program is assumed by End User. Clear Creek Solutions Inc. and the governmental licensee or sublicensees disclaim all warranties, either expressed or implied, including but not limited to implied warranties of program and accompanying documentation. In no event shall Clear Creek Solutions Inc. be liable for any damages whatsoever (including without limitation to damages for loss of business profits, loss of business information, business interruption, and the like) arising out of the use of, or inability to use this program even if Clear Creek Solutions Inc. or their authorized representatives have been advised of the possibility of such damages. Software Copyright© by : Clear Creek Solutions, Inc. 2005-2013; All Rights Reserved. Clear Creek Solutions, Inc. 6200 Capitol Blvd. Ste F Olympia, WA. 98501 Toll Free 1(866)943-0304 Local (360)943-0304 www.clearcreeksolutions.com 1.5in-hr with underdrain ELT 1-26-15 1/27/2015 3:16:22 PM Page 45 O WWHL44 1.5in-hr with unde,orain ELT 1-26-15 _ EJt: ❑ Gi ® A ftId d u (961 ® LMI i'Schematic - Analysis E3 SCENARIOS Flow Frequency- 10.0 10.0 Flow(efs) 0701 0801 ❑Predevelope Cumulative Probability 2 Year = 0,6875 0.0000 5 Year = 0.8413 0.0000 Mitigated 10 Year = 0.9412 0.0000 I Run Scenario + + 25 Year = 1.0663 0.0000 1.0 �.}+++.+++ + 1.0 50 Year = 1.1591 0.0000 Basic Elements + + + ++++i-h1-FVHMH � „ *. 100 Year = 1.2520 0.0000 ®® ® I m xxxxh + 701 Arvival Peaks 1949 0.7685 0.0000 ! D Wi �■� 1950 0.9762 0.0000 - _. 195 0. 0. 0 2 1952 0.5446 5446 0.0000000 1953 0.5876 0.0000 --. ---I 1954 0.6349 0.0000 Pro Elements 0.01 0.01 1955 0.7188 0.1556 5 1 2 5 10 20 30 50 7D ?0 = 65 gg 95951 1956 0.7834 0.0000 LID Toolbox i J 1957 0.8097 0.0303 Durations Flow Frequency I Water Quality j Hydrograph 1 Wetland Fluctuation 1958 0.6641 0.0000 1959 0.5533 0.0000 IL, Recharge Duration Recharge Predeveloped Recharge Mitigated 1960 0.6853 0.2597 Fr E j Analyze 1961 0.5713 0.0000 2 SEATAC SEE WORD FILE L\JEFF\PRECIP\DA-A !' 1962 0.6000 0.0000 C 1963 0.5634 0.0000 I 501 POC 1 Predevelo ed flow C 1964 0.6515 0.0000 Inflow ated �r ,POC-� ' E �� 1965 0.5874 0.0000 --'- 1000 Infiltration Bed ALL OUTLETS Mitigated 1966 0.6394 0.0000 Commercial Toolbox ( 1967 0.8606 0.0591 tool Infiltration Bed OUTLET 1 Mitigated i; se 1968 0.9575 0.0000 1969 0.6220 0.0000 I Precip Evap POC1 1970 0.6765 0.0000 r � 1971 0.6190 0.0000 Move Elements Flood Frequency Method 1972 0.8488 0.1434 ALL ` Log Pearson Type III 17B 1973 0.5778 0.0000 0' ----�- Weibull 1974 0.5867 0.0000 --- " Cunnane 1975 0.7993 0.1765 Gringorten 1976 0.5919 0.0000 J4VC LU QU i Y Gll� �J [Tue 3:04p-1 5in-hr with underdrain_ELT_1-26-15-Fi O W W HM4 1.5in-hr with underd rain_ELT-1-26-15 File Edit View Help Summary Report Gi; Ca 10 is Ad �'I Stficmatic rJ C�j ma's Analysis SCENARIOS Water Quality ism Run On-Line BMP Off-Line BMP ❑Predeveloei p I _ :Analysis ID Mitigated 24 hour Volume 10.3686 Run Scenario Standard Flow Rate 0.3435 Standard Flow Rate 0.1908 Basic Elements 15 Minute Flow Rate 0.3881 15 Minute Flow rate 10.2156 U _ Pro Elements A LID Toolbox ' Durations Flow Frequency Water Quality Hydrograph Wetland Fluctuation Recharge Duration Recharge Predeveloped Recharge Mitigated Analyze 1 PUYALLUP DAILY EVAP W/JENSEN-HAISE 2 SEATAC SEE WORD FILE 1:1JEFF\PRECIP\DK 501 P001 Predevelo ed flow 601 POC 1 Mitigated flow Commercial Toolbox I 1000 Infiltration Bed ALL OUTLETS Mitigated Precip Evap POC 1 j Move Elements Flood Frequency Method Log Pearson Type III 17B r. Weibull Cunnane i Gringorten i JQVC L-U"U X I i Tue 3:04p-1.5in-hrwith underdrain_ELT_1-26-15-Fi ®WWHM4 1.5in-hr with underdrain ELT 1-26-15 File Edit View Help Summary Report ❑ Liiik, _ d J is 61 Schematic <; _ �Analys,s ®r SCENARIOS _ Stage Pregnancy ❑Predevelo e� ® 1 Cumulative Probability 10 (feet) 1006 p j I 2 Year = 0.5752 0 Mitigated _ 5 Year = 0.5898 + + + 10 Year = 0.5982 Run Scenario 25 Year = 0.6079 50 Year = 0.6145 Basic Elements --- 100 Year = 0.6207 ®® ® I O Anneal Peaks a + 1006 1949 0.5777 m■® � 1950 0.6121 D ®® ! 1952 0.5711 548 - { 1952 0.5548 1953 0.5617 1954 0.5715 Pro Elements a1 p 1 1955 0.5662 A 0.5 1 2 5 10 20 30 50 70 80 90 95 98 9999.51 1956 0.5770 LID Toolbox 1957 0.5848 I Durations Flow Frequency Water Quality j Hydrograph Wetland Fluctuation 1958 0.5742 Recharge Duration Recharge Predeveloped Recharge Mitigated 1959 0.5584 1960 0.5713 r Analyze 1961 0.5531 1002 Infiltration Bed OUTLET 2 Mitigated 1962 0.5702 1003 Infiltration Bed STAGE Mitigated 1963 0.5762 1004 Bio Swale 1 ALL OUTLETS Mitigated 1964 0.5768 1005 Bio Swale 1 STAGE Miti ated 1965 0.5703 1966 0.5632 Commercial Toolbox 1967 0.5972 j 1007 Surface Bio Swale 1 OUTLET 1 Mitigated sr 1968 0.6131 1969 0.5613 Precip Evap POC 1 1970 0.5651 1971 0.5650 Move Elements Flood Frequency Method q � 1972 0.5940 �) Iro Log Pearson Type III 17B 1973 0.5528 0 (' Weibull 1974 0.5784 - € Cunnane 1975 0.5979 Gringorten 1976 0.5559 �ave Luau � � I " Ix Y R � !__ Tue 3:04p-1.5in-hr with underdrain_ELT_1-26-15-Fi Appendix C Conveyance Calculations and Flow Splitter CH2M HILL 3/18/2015 STORM PIPE DESIGN COMPUTATIONS-25 YEAR CONVEYANCE Project:City of Renton Sunset Terrace Regional Facility Return Year.25.00 Proj.No: 469392 Date: 1202015 By:ET Checked By r- Tributary at Point of Concentration Location Rainfall D/S Adjusted L Diam. Available Runoff Intensity ed Grade Slope of of Q Q V U/S D/S From To Length Nldth Ac Factor Sum 1., of Pipe Pipe Full Check Full Cover Cover Cover ID# ID# (ft) (ft) "A" "C" "CA" "CA" infir (it) (ft) (ft) (ft) - Pipe (ft) (n=) (in) 1s cfs (fps) check 1 2 3 4 7 8 9 10 11 12 13 14 18 19 20 21 22 25 26 27 28 29 30 31 32 33 SUNSET BLVD/10TH 2-3 2,250 2.83 2-3 2-5 134 1.79 0.9 1.61 1.61 1.75 2.83 348.17 344.32 342.06 340.29 1.32% 1.32% 134 0.012 18 13.13 ok 7.43 346.46 344.38 6.11 2-5 2-2 93 2.03 0.9 1.74 1.86 1.74 3.24 344.32 341.70 340.29 337.52 2.98% 2.98% 93 0.012 18 19.69 ok 11.14 344.56 344.71 4.03 2-2 2-7 45 4.58 0.9 0.00 1.86 1.73 3.22 341.70 340.33 337.08 335.96 2.49% 2.49% 45 0.012 18 18.00 ok 10.19 339.99 339.74 4.62 2.1 2-2 40 6.35 0.9 4.82 4.82 2.11 10.18 344.07 341.70 340.54 337.57 7.43% 7.43% 40 0.012 18 31.09 ok 17.59 342.36 342.96 3.53 2-2 RG 111 2.80 0.9 2.52 2.52 2.04 5.15 341.70 341.77 337.00 336.50 0.45% 0.45% 111 0.012 18 7.66 ok 4.33 342.96 343.53 4.70 DOWNSTREAM - SUNSET LANE 2.19 Used MGS Flood Output for 25- 3-1 3-2 15 2.90 year peak+flow from Inlet 44 2.19 339.73 339.10 332.75 332.59 4.20% 1.10% 15 0.012 12 4.06 ok 5.17 338.56 338.09 6.98 3-2 3-3 15 2.90 2.19 339.10 339.00 332.59 332.41 0.67% 1.17% 15 0.012 12 4.18 ok 5.32 338.09 338.17 6.51 3-3 3.4 26 2.90 2.19 339.00 339.00 332.41 332.11 0.00% 1.17% 26 0.012 12 4.18 ok 5.32 337.99 338.30 6.59 3-4 3-5 93 2.90 2.19 339.00 337.00 332.11 330.83 2.15% 1.37% 93 0.012 12 4.53 ok 5.77 338.17 337.45 6.89 3-5 3-6 82 2.90 2.19 337.00 336.94 330.83 329.76 0.07% 1.30% 82 0.012 12 4.42 ok 5.63 336.30 337.31 6.17 3-6 3-7 35 2.90 2.19 336.94 336.31 329.76 329.34 1.80% 1.20% 35 0.012 12 4.24 ok 5.40 337.39 337.18 7.18 Page 1 of 1 § { ( \§\)}§}})j!)§ §§§§§!§q§§§§q§666d6 ¥■ _. eaaaaaaa6...,..„ ����,������ �N m #! -»■#§§)§B§\)�\))§§§------ -----d ! aQ666 )§qk;§■j§§§§§ §§§\&§!§§\ a ��� � � , ) _ �6 6 6 6 6,6 6 6 d� !3|!!§g!y§§S95®B! ®/)`§ � ,� .,. # . � �k//� )\\(\d{)\kk\)\%kk\k\k\\k} kk-Ox / ! 0 9 !� , ( kn5§2 Be -------- NNN6c4 iwww, /f f .....................000.... )§)§§k)/§()§----- --------- ; \�; o,-==§--------- ?§? a` Z{k) =■!!5§l535§E55!§Be§y§§59555!§!| !!$#!] \RSS; ;� as \\ 0\IB5§a k k\�k\ �e,,,,,,,�.,,,,,.,,�,�„��,.,!■ k° 0k/k\ MGS FLOOD PROJECT REPORT Program Version: MGSFIood 4.12 Flow from Sunset Blvd and Program License Number: 200410003 NE 10th Run Date: 09/09/2014 3:24 PM Input File Name: Sunset Blvd & 10th_0909.fld Project Name: City of Renton Analysis Title: WQ Flows Comments: Renton Sunset PRECIPITATION INPUT Computational Time Step (Minutes): 15 Extended Precipitation Timeseries Selected Climatic Region Number: 13 Full Period of Record Available used for Routing Precipitation Station : 96004005 Puget East 40 in_5min 10/01/1939-10/01/2097 Evaporation Station 961040 Puget East 40 in MAP Evaporation Scale Factor 0.750 HSPF Parameter Region Number: 1 HSPF Parameter Region Name : USGS Default ********** Default HSPF Parameters Used (Not Modified by User) **********************WATERSHED DEFINITION *********************** ----------------------SCENARIO: PREDEVELOPED Number of Subbasins: 1 ---------- Subbasin : Exist---------- -------Area(Acres) -------- Till Forest 2.030 Till Pasture 0.000 Till Grass 0.000 Outwash Forest 0.000 Outwash Pasture 0.000 Outwash Grass 0.000 Wetland 0.000 Green Roof 0.000 User 0.000 Impervious 0.000 ---------------------------------------------- Subbasin Total 2.030 ----------------------SCENARIO: POSTDEVELOPED Number of Subbasins: 1 ---------- Subbasin : Proposed ---------- -------Area(Acres)-------- Till Forest 0.000 Till Pasture 0.000 Till Grass 0.000 Outwash Forest 0.000 Outwash Pasture 0.000 Outwash Grass 0.000 Wetland 0.000 Green Roof 0.000 User 0.000 Impervious 2.030 ---------------------------------------------- Subbasin Total 2.030 *** ****** Link: New Structure Lnk1 Basic Wet Pond Volume (91% Exceedance): 8992. cu-ft Computed Large Wet Pond Volume, 1.5*Basic Volume: 13488. cu-ft 2-Year Discharge Rate : 0.039 cfs 15-Minute Timestep,Water Quality Treatment Design Discharge On-line Design Discharge Rate(91% Exceedance): 0.30 cfs Off-line Design Discharge Rate (91% Exceedance): 0.16 cfs ***********Compliance Point Results Scenario Predeveloped Compliance Subbasin: Exist Scenario Postdeveloped Compliance Link: New Structure Lnk1 *** Point of Compliance Flow Frequency Data*** Recurrence Interval Computed Using Gringorten Plotting Position Predevelopment Runoff Postdevelopment Runoff Tr(Years) Discharge(cfs) Tr(Years) Discharge(cfs) ---------------------------------------------------------------------------------------------------------------------- 2-Year 0.043 2-Year 0.757 5-Year 0.071 5-Year 0.983 10-Year 0.095 10-Year 1.105 25-Year 0.120 25-Year 1.392 50-Year 0.154 50-Year 1.771 100-Year 0.167 100-Year 2.048 200-Year 0.259 200-Year 2.123 ** Record too Short to Compute Peak Discharge for These Recurrence Intervals MGS FLOOD PROJECT REPORT Flow from Shopping Mall Program Version: MGSFIood 4.12 Total Program License Number: 200410003 Run Date: 09/02/2014 12:27 PM Input File Name: Shopping_Mall_Total.fld Project Name: City of Renton Analysis Title: WQ Flows Comments: Renton Sunset PRECIPITATION INPUT Computational Time Step (Minutes): 15 Extended Precipitation Timeseries Selected Climatic Region Number: 13 Full Period of Record Available used for Routing Precipitation Station : 96004005 Puget East 40 in_5min 10/01/1939-10/01/2097 Evaporation Station 961040 Puget East 40 in MAP Evaporation Scale Factor 0.750 HSPF Parameter Region Number: 1 HSPF Parameter Region Name : USGS Default Default HSPF Parameters Used (Not Modified by User) WATERSHED DEFINITION ----------------------SCENARIO: PREDEVELOPED Number of Subbasins: 1 ---------- Subbasin : Exist---------- -------Area(Acres) -------- Till Forest 5.350 Till Pasture 0.000 Till Grass 0.000 Outwash Forest 0.000 Outwash Pasture 0.000 Outwash Grass 0.000 Wetland 0.000 Green Roof 0.000 User 0.000 Impervious 0.000 ---------------------------------------------- Subbasin Total 5.350 ----------------------SCENARIO: POSTDEVELOPED Number of Subbasins: 1 ---------- Subbasin : Proposed ---------- -------Area(Acres)-------- Till Forest 0.000 Till Pasture 0.000 Till Grass 0.000 Outwash Forest 0.000 Outwash Pasture 0.000 Outwash Grass 0.000 Wetland 0.000 Green Roof 0.000 User 0.000 Impervious 5.350 ---------------------------------------------- Subbasin Total 5.350 ----------------------SCENARIO: POSTDEVELOPED Number of Links: 1 Link: New Structure Lnk1 Basic Wet Pond Volume(91% Exceedance): 23697. cu-ft Computed Large Wet Pond Volume, 1.5"Basic Volume: 35546. cu-ft 2-Year Discharge Rate : 1.343 cfs 15-Minute Timestep,Water Quality Treatment Design Discharge On-line Design Discharge Rate (91% Exceedance): 0.78 cfs Off-line Design Discharge Rate(91% Exceedance): 0.43 cfs *** Point of Compliance Flow Frequency Data*`* Recurrence Interval Computed Using Gringorten Plotting Position Predevelopment Runoff Postdevelopment Runoff Tr(Years) Discharge(cfs) Tr(Years) Discharge (cfs) ---------------------------------------------------------------------------------------------------------------------- 2-Year 0.114 2-Year 1.994 5-Year 0.186 5-Year 2.590 10-Year 0.250 10-Year 2.913 25-Year 0.317 25-Year 3.667 50-Year 0.405 50-Year 4.668 100-Year 0.439 100-Year 5.397 200-Year 0.683 200-Year 5.594 '* Record too Short to Compute Peak Discharge for These Recurrence Intervals MGS FLOOD PROJECT REPORT Flow from Shopping Mall to Program Version: MGSFIood 4.12 Stormwater Facility Program License Number: 200410003 Run Date: 09/09/2014 3:28 PM Input File Name: Shopping_Center_Target0909.f1d Project Name: City of Renton Analysis Title: WO Flows Comments: Renton Sunset PRECIPITATION INPUT Computational Time Step (Minutes): 15 Extended Precipitation Timeseries Selected Climatic Region Number: 13 Full Period of Record Available used for Routing Precipitation Station : 96004005 Puget East 40 in_5min 10/01/1939-10/01/2097 Evaporation Station 961040 Puget East 40 in MAP Evaporation Scale Factor 0.750 HSPF Parameter Region Number: 1 HSPF Parameter Region Name : USGS Default Default HSPF Parameters Used (Not Modified by User) '`"**" **" """"WATERSHED DEFINITION ----------------------SCENARIO: PREDEVELOPED Number of Subbasins: 1 ---------- Subbasin : Exist---------- -------Area(Acres) -------- Till Forest 0.770 Till Pasture 0.000 Till Grass 0.000 Outwash Forest 0.000 Outwash Pasture 0.000 Outwash Grass 0.000 Wetland 0.000 Green Roof 0.000 User 0.000 Impervious 0.000 ---------------------------------------------- Subbasin Total 0.770 ----------------------SCENARIO: POSTDEVELOPED Number of Subbasins: 1 ----------Subbasin : Proposed ---------- -------Area(Acres)-------- Till Forest 0.000 Till Pasture 0.000 Till Grass 0.000 Outwash Forest 0.000 Outwash Pasture 0.000 Outwash Grass 0.000 Wetland 0.000 Green Roof 0.000 User 0.000 Impervious 0.770 ---------------------------------------------- Subbasin Total 0.770 Link: New Structure Lnk1 ********** Basic Wet Pond Volume(91% Exceedance): 3411. cu-ft Computed Large Wet Pond Volume, 1.5*Basic Volume: 5116. cu-ft 2-Year Discharge Rate : 0.022 cfs 15-Minute Timestep,Water Quality Treatment Design Discharge On-line Design Discharge Rate (91% Exceedance): 0.11 cfs Off-line Design Discharge Rate (91% Exceedance): 0.06 cfs ***********Compliance Point Results************* Scenario Predeveloped Compliance Subbasin: Exist Scenario Postdeveloped Compliance Link: New Structure Lnk1 *** Point of Compliance Flow Frequency Data*** Recurrence Interval Computed Using Gringorten Plotting Position Predevelopment Runoff Postdevelopment Runoff Tr(Years) Discharge (cfs) Tr(Years) Discharge (cfs) ---------------------------------------------------------------------------------------------------------------------- 2-Year 0.016 2-Year 0.287 5-Year 0.027 5-Year 0.373 10-Year 0.036 10-Year 0.419 25-Year 0.046 25-Year 0.528 50-Year 0.058 50-Year 0.672 100-Year 0.063 100-Year 0.777 200-Year 0.098 200-Year 0.805 ** Record too Short to Compute Peak Discharge for These Recurrence Interval SECTION 11 REFERENCES Appendix D Downstream Storm Drain Capacity 11-2 WBG103114IS3300SEA Culvert Design H/D = 6.2 O too 10,000 168 6,000 EXAMPLE (3) 156 6,000 0•+2 locM$(3.6 feet) 6. 5,000 a•120 cte 144 6. S. 4,000e A MR 132 0 red+ 3,000 (1) 2.3 0.e 5' 4. 120 a) :.1 7.4 H/D =5.5 2,000 (3) 2.2 7.7 4. 108 3 OD io teat 3' 96 1,000 3. 600 _ 84 600 // Y. 2__. 50040 72 400 w 300 60 u 200 H 1.3 z i w G 54 0 /" 4 W 100 2 > 4e .' Cr so a o i 6D d 1.0 1.0 42 W G on 30 ENTRANCE w 40 SCALE TYPE W 1,0 I-- 38 - 30 (1) Skiers sop alto i Q 9 . w Reod�all � •9 a 33 (2) Voovt dad alto 30 asadwell 2 8 8 (3) Groove end •6 27 Projecting 10 .T .T Y4 6 .7 6 70 off tools(2)or(31 Pre)eet 21 S norl:antauy to$Colo(1),rasa 4 vas atteldat locitned line taro"! D and 0 *Colo$,se revues a 6 3 illustrated. .6 18 2 IS S S 1.0 ____._'5 12 HEADWATER DEPTH FOR HEADWATER SCALES 2s3 CONCRETE PIPE CULVERTS REVISED MAY 1964 WITH INLET CONTROL a9Au OF KAllC ROAD! JAN.1903 Concrete Pipe Inlet Control Nomograph Figure 3-3.4.2A Hydraulics Manual Page 3-19 March 2007 0 200 400 800 Feet lw , w All s '� 41' �rr i Yd 34F �ry u '*" Q p u' ., .. _ _ o ........ .ro c Northeast Lot Residentia E Al M o � a a O or t r, i .ng Mall rrea c / b � 10 V Contributing Area for the existing storm drain on Harrington Ave downstream of Sunset LN • OBJECTID AREA NAME SHAPE_Length SHAPE-Area Impervious Residential (sf) (sf) 5 77,387.18 Sunset Blvd* 4571.592691 77387.18486 77,387.18 0 6 232,868.88 Shopping Mall Area 2315.915474 232868.8792 232,868.88 0 7 3,162.23 10th 453.3141323 3162.225676 3,162.23 0 9 2,620.10 10th to RG direct 421.3498754 2620.103182 2,620.10 0 10 6,090.60 Library* 338.7937015 6090.595876 6,090.60 0 11 425,652.95 Northeast Lot 3773.389852 425652.95 257,919.69 167,733.26 12 50,477.01 Glenwood 1115.740434 50477.01243 13,050.00 37,427.01 13 127,578.43 Northeast Lot Residen 1534 127,578.43 -- -- Part of 11 14 40,154.83 Northeast Lot Residen 1589 40,154.83 -- -- Part of 11 Area(ac) NAME Impervious Residential Ac Ac 5 1.78 Sunset Blvd* 1.78 - 6 5.35 Shopping_ Mall Area 5.35 - 7 0.1 10th 0.1 - 9 0.1 10th to RG direct 0.1 - 10 0.14 Library* 0.14 - 11,13,14 9.77 Northeast Lot 5.92 3.85 12 1.16 Glenwood 0.30 0.86 Subtotal 13.62 4.71 Total 18.33 * New area draining to 12-inch pipe on Harrington after facility is completed MGS FLOOD PROJECT REPORT Program Version: MGSFlood 4.34 Program License Number: 0 Run Date: 01/21/2015 9:31 AM Input File Name: SunsetFlow.fld Project Name: Analysis Title: Comments: PRECIPITATION INPUT Computational Time Step (Minutes): 15 Extended Precipitation Timeseries Selected Climatic Region Number: 13 Full Period of Record Available used for Routing Precipitation Station : 96004005 Puget East 40 in_5min 10/01/1939-10/01/2097 Evaporation Station 961040 Puget East 40 in MAP Evaporation Scale Factor 0.750 HSPF Parameter Region Number: 1 HSPF Parameter Region Name USGS Default Default HSPF Parameters Used (Not Modified by User) WATERSHED DEFINITION ----------------------SCENARIO: PRE-PROJECT Number of Subbasins: 4 ----------Subbasin : ShoppingMall---------- ------Area(Acres) -------- Till Forest 0.000 Till Pasture 0.000 Till Grass 0.000 Outwash Forest 0.000 Outwash Pasture 0.000 Outwash Grass 0.000 Wetland 0.000 Green Roof 0.000 User 2 0.000 Impervious 5.350 ---------------------------------------------- Subbasin Total 5.350 ----------Subbasin : 10th&Lib -------- ------Area(Acres)------- Till Forest 0.000 Till Pasture 0.000 Till Grass 0.000 Outwash Forest 0.000 Outwash Pasture 0.000 Outwash Grass 0.000 Wetland 0.000 Green Roof 0.000 User 2 0.000 Impervious 0.340 --------------------------------------- Subbasin Total 0.340 ----------Subbasin : Harrington&Palace-------- ------Area(Acres) -------- Till Forest 0.000 Till Pasture 0.000 Till Grass 3.850 Outwash Forest 0.000 Outwash Pasture 0.000 Outwash Grass 0.000 Wetland 0.000 • Green Roof 0.000 User 2 0.000 Impervious 5.920 Subbasin Total 9.770 --------Subbasin : Glennwood ---------- ------Area(Acres) -------- Till Forest 0.000 Till Pasture 0.000 Till Grass 0.860 Outwash Forest 0.000 Outwash Pasture 0.000 Outwash Grass 0.000 Wetland 0.000 Green Roof 0.000 User 2 0.000 Impervious 0.300 --------------------------------------- Subbasin Total 1.160 --------------------SCENARIO: POST-PROJECT Number of Subbasins: 5 ----------Subbasin : SunsetBlvd --------- ------Area(Acres) ------- Till Forest 0.000 Till Pasture 0.000 Till Grass 0.000 Outwash Forest 0.000 Outwash Pasture 0.000 Outwash Grass 0.000 Wetland 0.000 Green Roof 0.000 User 2 0.000 Impervious 1.780 ---------------------------------------------- Subbasin Total 1.780 ----------Subbasin : ShoppingMall---------- ------Area(Acres) -------- Till Forest 0.000 Till Pasture 0.000 Till Grass 0.000 Outwash Forest 0.000 Outwash Pasture 0.000 Outwash Grass 0.000 Wetland 0.000 Green Roof 0.000 User 2 0.000 Impervious 5.350 ---------------------------------------------- Subbasin Total 5.350 ----------Subbasin : 10th&Lib---------- ------Area(Acres) -------- Till Forest 0.000 Till Pasture 0.000 Till Grass 0.000 Outwash Forest 0.000 Outwash Pasture 0.000 Outwash Grass 0.000 Wetland 0.000 Green Roof 0.000 User 2 0.000 Impervious 0.340 ---------------------------------------------- Subbasin Total 0.340 ----------Subbasin : Harrington&Palace---------- ------Area(Acres) -------- Till Forest 0.000 Till Pasture 0.000 Till Grass 3.850 Outwash Forest 0.000 Outwash Pasture 0.000 Outwash Grass 0.000 Wetland 0.000 Green Roof 0.000 User 2 0.000 Impervious 5.920 ---------------------------------------------- Subbasin Total 9.770 ----------Subbasin : Glennwood ---------- ------Area(Acres) -------- Till Forest 0.000 Till Pasture 0.000 Till Grass 0.860 Outwash Forest 0.000 Outwash Pasture 0.000 Outwash Grass 0.000 Wetland 0.000 Green Roof 0.000 User 2 0.000 Impervious 0.300 --------------------------------------------- Subbasin Total 1.160 ***** «**** ************* LINK DATA************ «***************** ----------------------SCENARIO: PRE-PROJECT Number of Links: 2 ------------------------------------------ Link Name: Harrington&SunsetBlvd Link Type: Copy Downstream Link: None ------------------------------------------ Link Name: Harrington&10th Link Type: Copy Downstream Link Name: Harrington&SunsetBlvd ************************* LINK DATA«******** ********************* ---------------------SCENARIO: POST-PROJECT Number of Links: 2 ------------------------------------------ Link Name: Harrington&SunsetBlvd Link Type: Copy Downstream Link: None ------------------------------------------ Link Name: Harrington&10th Link Type: Copy Downstream Link Name: Harrington&SunsetBlvd **********************FLOOD FREQUENCY AND DURATION STATISTICS******************* ----------------------SCENARIO: PRE-PROJECT Number of Subbasins: 4 Number of Links: 2 ----------------------SCENARIO: POST-PROJECT Number of Subbasins: 5 Number of Links: 2 ***********Groundwater Recharge Summary************* Recharge is computed as input to Perind Groundwater Plus Infiltration in Structures Total Predeveloped Recharge During Simulation Model Element Recharge Amount(ac-ft) ----------------------------------------------------------------------------------------------- Subbasin: ShoppingMall 0.000 Subbasin: 10th&Lib 0.000 Subbasin: Harrington&Palace 470.511 Subbasin: Glennwood 105.101 Link: Harrington&SunsetBly Not Applicable Link. Harrington&10th Not Applicable Total: 575.612 Total Post Developed Recharge During Simulation Model Element Recharge Amount (ac-ft) ---------------------------------------------------------------------------------------------- Subbasin: SunsetBlvd 0.000 Subbasin: ShoppingMall 0.000 Subbasin: 10th&Lib 0.000 Subbasin: Harrington&Palace 470.511 Subbasin: Glennwood 105.101 Link: Harrington&SunsetBly Not Applicable Link: Harrington&10th Not Applicable Total: 575.612 Total Predevelopment Recharge Equals Post Developed Average Recharge Per Year, (Number of Years= 158) Predeveloped: 3.643 ac-ft/year, Post Developed: 3.643 ac-ft/year ***********Water Quality Facility Data************* ----------------------SCENARIO: PRE-PROJECT Number of Links: 2 ----------------------SCENARIO: POST-PROJECT Number of Links: 2 ***********Compliance Point Results************* Scenario Pre-Project Compliance Link: Harrington&SunsetBlvd Scenario Post-Project Compliance Link: Harrington&SunsetBlvd *** Point of Compliance Flow Frequency Data*** Recurrence Interval Computed Using Gringorten Plotting Position Predevelopment Runoff Postdevelopment Runoff Tr(Years) Discharge (cfs) Tr(Years) Discharge (cfs) 2-Year 4.845 2-Year 5.495 5-Year 6.177 5-Year 7.046 10-Year 7.503 10-Year 8.516 25-Year 10.203 25-Year 11.423 50-Year 11.797 50-Year 13.229 100-Year 14.750 100-Year 16.546 200-Year 14.921 200-Year 16.782 ** Record too Short to Compute Peak Discharge for These Recurrence Intervals **** Flow Duration Performance**** Excursion at Predeveloped 50%Q2 (Must be Less Than 0%): 62.9% FAIL Maximum Excursion from 50%Q2 to Q2 (Must be Less Than 0%): 75.2% FAIL • Maximum Excursion from Q2 to Q50 (Must be less than 10%): 99999.0% FAIL Percent Excursion from Q2 to Q50 (Must be less than 50%): 100.0%FAIL FLOW DURATION DESIGN CRITERIA: FAIL **** LID Duration Performance**** Excursion at Predeveloped 8%Q2 (Must be Less Than 0%): 14.0% FAIL Maximum Excursion from 8%Q2 to 50%Q2 (Must be Less Than 0%): 62.9% FAIL LID DURATION DESIGN CRITERIA: FAIL Appendix E Design Drawings CITY OF RENTON SUNSET TERRACE REGIONAL STORMWATER FACILITY 2015 LIST OF DRAWINGS 1 G-1 COVER SHEET 2 G-2 ABBREVIATIONS/LEGEND/GENERAL NOTES FUNDED IN PART BY THE WASHINGTON 3 G-3 SURVEY CONTROL/NOTES STATE DEPARTMENT OF ECOLOGY 4 G'l EXIS GENERAL NOTES 5 E-1 EXISTING CONDITIONS PRIOR TO CONSTRUCTION 2012 STORMWATER RETROFIT AND LID 6 C-1 SITE PREPARATION AND TESC PLAN 7-10 C-2-C- 5 STE PLAN AND PROFILE COMPETITIVE PROGRAM,GRANT NO.G1200544 100% SUBMITTAL— NOT FOR CONSTRUCTION 11-13 C-6-C-8 SECTIONS/DETAILS 14 C-9 PAVEMENT RESTORATION PLAN 15 W-1 WATER PLAN 16 L-1 PLANTING PLAN 17 L-2 PLANTNG SCHEDULE,NOTES,ABBV,LEGEND&DETAILS 18 L-3 PLANTING DETAILS 19 IR-1 IRRIGATION PLAN 20 I R-2 IRRIGATION SCHEDULE,NOTES,ABBV&DETAILS 21 IR-3 IRRIGATION DETAILS I a N JGTHf ST f oy Creek 21 N D � sNOHOMISH LO. `, I�� B T LL KING CO, f m a�• .� GwaL i• N £ — NE 11T11 • EOMONO t LA } w ,ol rcl o� TTLE ME P •oMNAT10N �1y� C �� w� r ��/� • EF� saw o � NE 16 I TH 5T r FALL EW SAQDAN e O y - �— — IAXE wAsxiNGTGNsT sN • [ 405 +< Sr a w c-a 1(\`{ NE 12TM ST ✓/ •RENTON NORTN �"� a BENDy�� '4 J �I O l� 9LVp I�`J"- �l Q oes w s a x ti. —�t_.. ! C-3 LD p ,r' s� ONES 1 g I • •vaLEr ° PROJECT `tea ` Z. ,( ,,,j NE io ? I U g. s _ LOCATION 1i y \ < yCzW z �R { �i A o� - w, 4 rryc Au4urw 9 DIAMOND 'IT z erz ._5i z t �I LOCATION Z ", i NE �t� SITE PLAN SHEET LAYOUT 71 NOT TO SCALE s LOCATION MAP VICINITY MAP i° NOT TO SCALE NOT TO SCALE d 4c`y Q m��] AS NOTED ` .....�'•` n CITY OF z/zz/�s CH2MHILL $'M SUNSET TERRACE REN ON REGIONAL STORMWATER FACILITY M n Public Wwka O pl. i„y/ewmmy/ COVER SHEET qNO, REVISION By DPTE A— _21 LEGEND ABBREVIATIONS GENERAL NOTES NOTES AP ANGEE POINT 1. ALL WORK AND MATERIALS SHALL BE IN ACCORDANCE WITH THE CITY OF RENTON STANDARDS EXISTING PROPOSED DESCRIPTION APPROX APPROXIMATE AND SPECIFICATIONS AND WASHINGTON STATE DEPARTMENT OF TRANSPORTATION"STANDARD 1.ALL SIGNS SHALL BE MOUNTED ON -._w POSTS UNLESS OTHERWISE SPECIFICATIONS FOR ROAD,BRIDGE,AND MUNICIPAL CONSTRUCTION;2014 AND AS AMENDED SPECIFIED. RIGHT OF WAY BLDG BUILDING BY CITY OF RENTON SUPPLEMENTAL SPECIFICATIONS AND THE CONTRACT SPECIAL BOT BOTTOM FIRONSIONS. 2.BOTTOM OF LOWEST SIGN SHALL BE AT LEAST 7.0'ABOVE FINISH GRADE. -- EASEMENT FOR 2 OR MORE SIGNS,BOTTOM OF LOWEST SIGN SHALL BE AT LEAST CONTOUR INTERVAL CB CATCH BASIN 2. ALL WORK WITHIN THE SITE SHALL BE SUBJECT TO THE INSPECTION OF THE CITY ENGINEER 6.0'ABOVE FINISH GRADE --- --- CONTOUR INDEX CPEP CORRUGATED POLYETHYLENE PIPE OR DESIGNATED REPRESENTATIVE. I CENTER LINE 3.SIGNS SHOULD BE MOUNTED ON POST IN A WAY THAT THE OUTSIDE EDGE BUILDING EDGE CMP CORRUGATED METAL PIPE 3. PRIOR TO BEGINNING CONSTRUCTION,THE CONTRACTOR SHALL MEET WITH THE CITY SHALL BE AT LEAST 24'FROM THE PROJECTION OF THE FACE OF CURB, BUILDING OVERHANG COM COMMON ENGINEER FOR A PRE-CONSTRUCTION MEETING. COMM COMMUNICATION 4.PAINTING. THE FACE AND EDGES OF THE 1/2 INCH PLYWOOD SIGN BOARD --- -- - - EDGE OF PAVEMENT COMP COMPACTED 4. A COPY OF THESE APPROVED PLANS AND PROJECT SPECIFICATIONS MUST BE ON THE SITE SHALL HAVE ONE PRIME COAT AND TWO COATS OF EXTERIOR ENAMEL. ------ LANE LINE CO NC CONCRETE WHENEVER CONSTRUCTION IS IN PROGRESS. THE POSTS,BRACES AND BACK OF SIGN BOARD SHALL HAVE ONE COAT CP CONTROL POINT OF PRIMER AND EXTERIOR ENAMEL. THE BACKGROUND COLOR IS WHITE. FENCE LINE CTRL CONTROL S. PRIOR TO ANY SITE CONSTRUCTION THAT INCLUDES CLEARING OR GRADING,THE SITE FENCE LINE CONSTRUCTION LIMITS SHALL BE LOCATED AND IDENTIFIED BY THE CONTRACTOR' SHALL BE PROJECT 5.LETTER TYPES. THE LETTER TYPE SHA BE SOLID HELVETICA MEDIUM DEPT. DEPARTMENT SURVEYOR AND APPROVED BY THE CITY. EXCEPT THE LOGO WHICH WILL BE PROVIDED BY THE CITY. ALL LETTERS RETAINING WALL DIA DIAMETER AND NUMBERS WILL BE BUCK. -.-W----W UNDERGROUND CABLE-TV LINE D/W DRIVEWAY 6. TEMPORARY EROSION AND SEDIMENT CONTROL FACILITIES SHALL BE CONSTRUCTED PRIOR TO DWG DRAWING ANY GRADING OR EXTENSIVE LAND CLEARING IN ACCORDANCE WITH APPROVED TEMPORARY 6.LETTER SIZE. 4'LETTERS ARE 1/2'WIDE;3'LETTERS ARE 3/8'WIDE; ----.- .-- UNDERGROUND COMMUNICATION LINE EROSION AND SEDIMENT CONTROL PLAN.THESE FACILITIES MUST BE SATISFACTORY 2"LETTERS ARE 1/4-WIDE. .--.--�- OVERHEAD ELECTRICAL LINE E EASTING MAINTAINED UNTIL CONSTRUCTION AND LANDSCAPING IS COMPLETED AND THE POTENTIAL FOR ELEC ELECTRICAL ON-SITE EROSION HAS PASSED. I UNDERGROUND ELECTRICAL LINE ELEV/EL ELEVATION o- +y UNDERGROUND FIBER OPTIC LINE EOP EDGE OF PAVEMENT 7. PUBLIC STREETS SHALL BE CLEANED ONCE PER DAY OR AS DIRECTED BY THE CITY. 2' I ESC EROSION AND SEDIMENTATION CONTROL FLUSHING STREETS WITH WATER WILL NOT BE ALLOWED. Sunxl lard¢R AamNala Facility o NATURAL GAS LINE EXIST/EX EXISTING I y - SANITARY SEWER LINE B. DEPICTED ILE FOR V OF EXISTING UTILITIES ARE ONS OF EXIS THE CONTRACTOR SHALL BE FT FEET RESPONSIBLE FOR VERIFYING THE ACTUAL LOCATIONS OF EXISTING UTILITIES CONTRACTOR TO tcOax Was iftgtml t e D A pal of Ne _____-_____■__n STORM DRAIN LINE CONSTRUCTION.UTILITIES SHOWN ARE FOR THE PURPOSE OF ASSISTING THE CONTRACTOR IN NYdhAgim$101!Ulpor6nml O(Ecology CALV GALVANIZED LOCATING SAID UTILITIES, CONTRACTOR SHALL CONTACT UNDERGROUND UTILITIES LOCATION ____________ UNDERDRAIN LINE GPS GLOBAL POSITIONING SYSTEM CENTER(1-800-424-5555)48 HOURS PRIOR TO BEGINNING OF CONSTRUCTION AND DEP10■NO OOO 4 GV GATE VALVE OBTAIN ON-SITE UTILITY LOCATIONS. CITY O RENE117TON OF EURFA Y GRANT: $7,2W M --- WATER LINE CRY OF R6NfON SURFACE WATER N911Y TOTAL 1,2500 41 CONTROL POINT(MISCELLANEOUS) HORIZ HORIZONTAL 9. CONTRACTOR SHALL COMPLY WITH ALL PERMITS CONDITIONS AND REQUIREMENTS BY THE TorAL f1,250,000 CONTROL POINT(OTHER) CITY OF RENTON.SEE APPROVED PERMITS AND PERMIT REQUIREMENTS IN PROJECT SPECIAL CONSTRUCTION YCTION �ACT"O'/ES/OO TEM,AbeoWoWemm�n{m CONSTRUCTION CONTRACT tad i'(saerded amount) ID INSIDE DIAMETER PROVISIONS. CONTRACTOR.( h cooled info) SATE POST IE INVERT ELEVATION SCNEONE:(month/Tau b mooWR^r) s + SINCLL POST SIGN 10.CONTRACTOR SHALL BE RESPONSIBLE FOR PREPARATION OF TRAFFIC CONTROL PLANS AND LF UNEAL FOOT CONSTRUCTION STORM WATER POLLUTION PREVENTION PLAN(CSWPPP).CONTRACTOR SHALL 1, •ag•12 EXTERIOR PLYWOOD DOUBLE POST SIGN LP LOW POINT SUBMIT PLANS TO ENGINEER FOR APPROVAL PRIOR TO IMPLEMENTATION. (SMOOTH BOTH SUES.ABX) o ■ MAILBOX LT LEFT,LIGHTING JUNCTION BOX YX4•DIAGONAL BRACE 11.DRAINAGE STRUCTURES SHALL CONFORM TO CITY OF RENTON STANDARD DETAILS. TO'ABOVE 9 BOREHOLE MAX MAXIMUM OF STDABTR,TW MH MANHOLE 12.FOR CATCH BASINS AT THE CURB,THE OFFSETS SHOWN ON PLANS ARE TO THE FACE OF ROADWAY COMMUNICATION MANHOLE MIN MINIMUM '1(4'XIY VERTICAL PORTS (MN) CURB.FOR ALL OTHER STRUCTURES,THE OFFSETS ARE TO THE CENTER OF STRUCTURE. TREATED,TYP L SANITARY SEWER MANHOLE MISC. MISCELLANEOUS u ® STORM DRAIN CATCH BASIN MON. MONUMENT 13.ALL PIPE TRENCH BACKFILL SHALL BE GRAVEL BORROW UNLESS THE NATIVE SOIL IS APPROVED BY THE ENGINEER AS SUITABLE FOR BACKFILL. STORM DRAIN MANHOLE OR N NORTHING b ® NAVD NORTH AMERICAN VERTICAL DATUM 14.FOR STORM DRAIN CROSSINGS OF UTILITIES WHERE THERE IS LESS THAN 1'-0"VERTICAL CATCH BASIN TYPE 2 NOVO NATIONAL GEODETIC VERTICAL DATUM CLEARANCE BETWEEN PIPES,PLACE 1'X 1'X 4'STYRENE FOAM BETWEEN PIPES. COMMUNICATION UTILITY PEDESTAL No NUMBER O GUY ANCHOR NTS NOT TO SCALE 15.BEDDING FOR STORM SEWER PIPE SHALL BE PER CITY OF RENTON STANDARD PLAN 220.00 "PIPE COMPACTION DESIGN AND BACKFILL". a'- GUY POLE OC ON CENTER 0- 1 LIGHT POLE WITH ONE ARM �'W ORDINARY HIGH WATER 16.TRANFFTIICCCCONTROL PAVEMENTTOR SHALL BE PoMARKINGS DURING NSIBLE FOR PRO MOTING CO STRUCTION,AAND RESTORATIO VEHICLE N DETECTION AND �* POWER POLE PC POINT OF CURVATURE VEHICLE DETECTION AND TRAFFIC CONTROL MARKINGS. PROJECT SIGN i{F LIGHT POLE WITH NO ARM PROP PROPOSED PT POINT OF TERMINAL DETAIL R ELECTRICAL JUNCTION BOX ) cm ELECTRICAL PANEL BOX R RADIUS NTSREF REFERENCE TYP 0 FIBER JUNCTION BOX RENF REINFORCEMENT SECTION INDICATOR DETAIL INDICATOR ■ GAS VALVE ROW RIGHT OF WAY FIT RIGHT DRAWING ON WHICH SECTION IS CUT(C-1): DRAWING ON WHICH DETAIL IS REFERENCED(C-1): D CATCH BASIN SO STORM DRAIN ASECTION LETTER DETAIL NUMBER m TRAFFIC JUNCTION BOX SOCB STORM DRAIN CATCH BASIN A FIRE HYDRANT SDMH STORM DRAIN MANHOLE p_ C-5 SS SANITARY SEWER DRAWING REFERENCE NUMBER FIRE DEPARTMENT CONNECTOR STA STATION DRAWING REFERENCE NUMBER & WATER VALVE FIN STD STANDARD ON WHICH SECTION APPEARS Z ON WHICH DETAIL APPEARS 3 w N WATER VALVE T TOWNSHIP DRAWING ON WHICH SECTION APPEARS(C-5): DRAWING ON WHICH DETAIL APPEARS(C-5): U 6 ■ WATER METER TJB TELEPHONE JUNCTION BOX Z { TREE TYPO TYPICAL LARY EROSION AND SEDIMENT CONTROL SECTION /i SECTION LETTER DETAIL ,� DETAIL NUMBER K e X 7 BUSH UTE UTILITY SCALE C-1 SCALE C-1 Z STUMP UNOGND UNDERGROUND { ■ WATER PRESSURE REDUCTION VALVE DRAWING REFERENCE DRAWING REFERENCE U _ VERT VERTICAL NUMBER ON WHICH NUMBER ON WHICH SECTION IS CUT DETAIL IS REFERENCED WM WATER METER DRAINAGE STRUCTURE 10: 44t WSDOT WASHINGTON STATE DEPT.OF TRANSPORTATION ii ASEL WATER SURFACE ELEVATION %-Y 9 WV WATER VALVE Z DRAINAGE STRUCTURE NUMBER , SITE PLAN DRAWING NUMBER J Q NSA CSUNSETITY OF `:n/,s $ CH2MHILL ivPRavA „m �� ±I� LSTORTERRACE RENTON REGIONAL STORMWATER FACILITY n _ onmV ,,,,;,,yVe�namy/Paer�Wan..o.m. ABBREVIATIONS I LEGEND I GENERAL NOTES .»G-2 9 EvSc�, cn-E WPR �� �'�� 1 Rt HORIZONTAL AND VERTICAL CONTROL POINT ID NORTHING FASTING ELEV DESCRIPTIONS CH2O7 184877.669 1307111.594 337,391 SET PIK NAIL IN SEAM,TOP OF CURB O BACK OF H.C.RAMP,26'E.&46'S.OF CL INTX FOR NE SUNSET BLVD&HARRINGTON AVE NE CH2O9 185096.822 1306957.430 336,171 SET PK NAIL. 19'W.OF CL FOR HARRINGTON AVE NE.26'N.OF CL FOR SUNSET LN NE CH210 185347.824 1306917.238 338.323 SET PK NAIL IN TOP OF WESTERLY CURB, 12'W.OF CL FOR HARRINGTON AVE NE,33'S.OF CL FOR GLENNWOOD AVE NE CH211 184937.706 1307017.452 334.384 SET PUNCH MARK IN SOUTH CORNER OF RIM FOR JBOX O NW CORNER OF NE SUNSET BLVD&HARRINGTON AVE NE CH212 185793.135 1306939.480 344.599 SET PK NAIL,OPPOSITE FY HYD, 10'E.OF CL FOR HARRINGTON AVE NE,AT ENTRANCE TO APARTMENT COMPLEX O 1100 HARRINGTON AVE NE CH216 186735.128 1306987.721 353.484 FND 2"BRASS CAP SET IN MON CASE&COVER(ON+/-0.80'),CL INTX FOR NE 13TH ST AND HARRINGTON AVE NE CH225 iB5503.352 1307031.014 339.261 SEf PK NAIL ALONG NE 10TH ST- 18"S.OF NORTH FL. 100'WEST OF CL HARRINGTON AVE NE CH226 iB5403.756 1307202.389 342.069 SET PK NAIL ALONG NORTHERLY EDP FOR NE 10TH ST,80'SE OF CL FOR SUNSET LN NE CH227 185335.742 1307300.825 345.576 SET PK NAIL ALONG NORTHERLY EDP FOR NE IOTH ST, 110'NW OF CL FOR NE SUNSET BLVD IS17186• 186452.823 1306190.370 1 326.432 FND 3"BRASS CAP SET IN MON CASE&COVER(DN+/- 1.10'),CL INTX FOR EDMONDS AVE NE&NE 12TH ST(AKA"RENT 57") •PROJECT BENCHMARK SURVEY CONTROL NOTES: 1. HORIZONTAL DATUM IS NAD 83/91, HORIZONTAL COORDINATES SHOWN HEREIN ARE WASHINGTON STATE PLANE COORDINATE SYSTEM, NORTH ZONE,U.S.SURVEY FEET. 2. VERTICAL DATUM IS NAVD88,FEET.PROJECT BENCHMARK: 9S17186",FND BRASS DISK SET IN CONC,IN MON CASE&COVER(DN +/-0.5').CL INTERSECTION FOR NE 12TH ST&EDMONDS AVE NE.EL=326.432' 3. SURVEY CONTROL AS SHOWN HEREON,IS FOR CONSTRUCTION PURPOSES ONLY.CH2M HILL HOLDS ALL BACKGROUND DATA AND RECORDS USED IN CALCULATIONS FOR ROADWAY CENTERLINES,CONSTRUCTION CENTERLINES,AND DERIVATION OF VALUES FOR USTED SURVEY CONTROL POINTS,AS LISTED IN THIS PLAN SET.NO OTHER ACCURACIES OR RENDERINGS OF BOUNDARY OR ROADWAY DATA IS IMPLIED OR PORTRAYED,AND IS NOT COVERED UNDER THE CURRENT CONTRACT FOR THIS WORK. 4. NOT ALL SURVEY CONTROL POINTS SHOWN HEREIN ARE PERMANENT IN NATURE.THEY ARE SHOWN IN THIS MANNER TO ASSIST WITH INTERVISIBILITY FOR CONSTRUCTION PURPOSES. 5. IT WILL BE THE RESPONSIBILITY OF THE CONTRACTOR TO PRESERVE ALL EXISTING RIGHT OF WAY MONUMENTATION.AS SHOWN ON THE INDIVIDUAL SHEETS.IN ACCORDANCE WITH RCW 58.24.040(8).NO CADASTRAL OR GEODETIC SURVEY MONUMENT MAY BE OISTURBED WITHOUT A VALID PERMIT TO REMOVE OR DESTROY A SURVEY MONUMENT,ISSUED BY THE WASHINGTON STATE DEPARTMENT OF NATURAL RESOURCES.PERMIT APPLICATIONS CAN BE OBTAINED BY CALUNG THE PUBLIC LAND SURVEY OFFICE AT (360)902-1194.THE PERMIT APPLICATION MUST BE STAMPED BY A REGISTERED WASHINGTON STATE LAND SURVEYOR.SEE SPEC PROVISION 1-07.6. 6. BASIS OF BEARING:CENTERLINE FOR HARRINGTON AVE NE:S 03'37'55'W. 7. BASIS OF POSITION: FND MIC.CL INTX FOR NE 12TH ST&HARRINGTON AVE NE. 8. THE EXISTING RIGHT-OF-WAY LINES.AS DEPICTED ON THESE SHEETS.WERE CALCULATED BY OTHERS.CH2MHILL MAKES NO CLAIMSAS TO THE ACCURACY OF THE CALCULATED RIGHT-OF-WAY LINES,NOR WILL CH2MHILL BE HELD RESPONSIBLE FOR ANY CLAIMSRESULTING FROM ERRORS MADE IN THE CALCULATIONS OF SAID LINES AS THEY RELATE TO THE LOCATIONS OF THE DETAILED DESIGN IMPROVEMENTS. K gg3 R 8 N 5 4 z s } 9 -�Ir�i SAS NOTED 2/2)/15 /� FOR _ CITY OF SUNSET TERRACE FT7 g CH2MHILL a �PNovu \ „„. DATUM RENT TON REGIONAL STORMWATER FACILITY eY � m""my/eN�Mmy/P�am wom Oepl. SURVEY CONTROL/NOTES C-3 y NO. REVISION "�M } 21 TEMPORARY EROSION/SEDIMENT CONTROL (TESC) GENERAL NOTES GENERAL REQUIREMENTS BMP INSTALLATION, MAINTENANCE, AND DISCHARGES BMP INSTALLATION, MAINTENANCE, AND DISCHARGES (CONTINUED) 1. THE ESC FACILITIES SHOWN ON THIS PLAN MUST BE CONSTRUCTED PRIOR TO OR IN 1. INLET PROTECTION SHALL BE INSTALLED IN ANY ROAD OR PARKING LOT DRAINAGE 12, IF ANY PART(S)OF THE CLEARING LIMIT BOUNDARY OR TEMPORARY EROSION/SEDIMENTATION CONJUNCTION WITH ALL CLEARING AND GRADING ACTIVITIES IN SUCH A MANNER AS SYSTEM INLETS,EXISTING OR NEWLY INSTALLED,WHICH ARE LIKELY TO RECEIVE CONTROL MEASURE(S)IS/ARE DAMAGED,IT SHALL BE REPAIRED IMMEDIATELY. TO ENSURE THAT SEDIMENT-LADEN WATER DOES NOT ENTER THE DRAINAGE RUNOFF FROM THE DISTURBED AREAS DURING CONSTRUCTION. INLET PROTECTION SYSTEM OR VIOLATE APPUCABLE WATER QUALITY STANDARDS. WHEREVER POSSIBLE, SHOWN ON THE TESC PLANS ARE APPROXIMATE LOCATIONS, THE CONTRACTOR SHALL 13. ALL PROPERTIES ADJACENT TO THE PROJECT SITE SHALL BE PROTECTED FROM SEDIMENT MAINTAIN NATURAL VEGETATION FOR SILT CONTROL. ADD INLET PROTECTION AS NECESSARY TO ALL CATCH BASINS THAT RECEIVE STORM DEPOSITION AND RUNOFF. WATER RUNOFF WITHIN THE PROJECT AREA AND THAT MAY OR MAY NOT BE SHOWN ON 2. THE ESC FACILITIES SHOWN ON THIS PLAN ARE THE MINIMUM REQUIREMENTS FOR THE TESC PLANS. 14. DO NOT FLUSH CONCRETE BY-PRODUCTS IWO THE STORM ANTICIPATED SITE CONDITIONS.DURING THE CONSTRUCTION PERIOD,THESE ESC DRAINAGE SYSTEM. IF EXPOSED AGGREGATE IS FLUSHED INTO THE STORM SYSTEM,IT COULD FACILITIES SHALL BE UPGRADED(E.G..ADDITIONAL SUMPS,RELOCATION OF HIGH 2. AT NO TIME SHALL MORE THAN 1 FOOT OF SEDIMENT BE ALLOWED TO ACCUMULATE MEAN RE-CLEANING THE ENTIRE DOWNSTREAM STORM SYSTEM.OR POSSIBLY RE-LAYING VISIBILITY FENCE AND ADDITIONAL BERMS,ETC.)AS NEEDED FOR UNEXPECTED WITHIN A CATCH BASIN.ALL CATCH BASINS AND CONVEYANCE LINES SHALL BE THE STORM LINE. STORM EVENTS. ADDITIONALLY,MORE ESC FACILITIES MAY BE REQUIRED TO CLEANED AT THE COMPLETION OF THE PROJECT. THE CLEANING OPERATION SHALL ENSURE COMPLETE SILTATION CONTROL.THEREFORE,DURING THE COURSE OF NOT FLUSH SEDIMENT-LADEN WATER INTO THE DOWNSTREAM SYSTEM. 15. THE CONTRACTOR SHALL NOT DISCHARGE TURBID WATER GENERATED FROM CONSTRUCTION CONSTRUCTION IT SHALL BE THE OBLIGATION AND RESPONSIBILITY OF THE CONTRACTOR ACTIVITIES,DIRECTLY TO ANY STREAMS,STORM WATER SYSTEM INLETS.OR DRAINAGE DITCHES TO ADDRESS ANY NEW CONDITIONS THAT MAY BE CREATED BY HIS ACTIVITIES AND TO 3. THE CONTRACTOR SHALL NOT CONVEY RUNOFF TO THE INFILTRATION FACILITY OR IN ACCORDANCE WITH THE GENERAL PERMIT. PROVIDE ADDITIONAL FACILITIES OVER AND ABOVE THE MINIMUM REQUIREMENTS AS MAY BIORETENTION CELL GRADING UNTIL THE PROJECT SITE DRAINING TO THE BIORETENTION BE NEEDED. AREA HAS BEEN STABILIZED AND AUTHORIZATION IS GIVEN BY THE ENGINEER.PRIOR TO 16. THE CONTRACTOR SHALL NOT DISCHARGE ANY CLEANING SOLVENTS OR CHEMICALS UTILIZED THE AREA BEING STABILIZED AND BIORETENTION SWALES BEING PLANTED,RUNOFF FOR TOOL OR EQUIPMENT CLEANING TO THE GROUND. REFUELING OF EQUIPMENT SHALL BE 3. THE ESC FACILITIES SHALL BE INSPECTED BY THE PERMITTEE/CONTRACTOR DAILY SHALL BE PREVENTED FROM ENTERING THE BIORETENTION SWALES. CONDUCTED AWAY FROM THE DRAINAGE FACILITIES AND DONE IN SUCH A MANNER AS TO DURING NON-RAINFALL PERIODS, EVERY HOUR(WORKING HOURS)OR EVERY EIGHT PREVENT SPILLS FROM ENTERING THE GROUNDWATER OR WATER BODIES(INCLUDING WETLANDS). HOURS(NON-WORKING HOURS)DURING A RAINFALL EVENT AND AT THE END OF 3. ALL DENUDED SOILS MUST BE STABILIZED WITH AN APPROVED TESC METHOD SPILLS SHOULD BE PREVENTED FROM HITTING THE GROUND PER CSWPPP. EVERY RAINFALL,AND MAINTAINED AS NECESSARY TO ENSURE THEIR CONTINUED (E.G.SEEDING,MULCHING,PLASTIC COVERING,CRUSHED ROCK)WITHIN THE FOLLOWING FUNCTIONING. IN ADDITION,TEMPORARY STORAGE TANK/POND AND ALL TEMPORARY TIMELINES: 17. THE CONTRACTOR SHALL SET ASIDE A SEPARATE AREA FOR THE WASH-OUT OF CONSTRUCTION SILTATION CONTROLS SHALL BE MAINTAINED IN A SATISFACTORY CONDITION UNTIL SUCH A. MAY 1 TO SEPTEMBER 30-SOILS MUST BE STABILIZED WITHIN 7 DAYS OF EQUIPMENT AND TOOLS. TIME THAT CLEARING AND/OR CONSTRUCTION IS COMPLETED,PERMANENT DRAINAGE GRADING. FACILITIES ARE OPERATIONAL.AND THE POTENT FOR EROSION HAS PASSED. S.OCTOBER 1 TO APRIL 30 -SOILS MUST BE STABILIZED WITHIN 2 DAYS OF 18. THE CONTRACTOR SHALL PROPERLY DISPOSE OF ALL CONSTRUCTION DEBRIS IN AN APPROVED WRITTEN RECORDS SHALL BE KEPT DOCUMENTING THE REVIEWS OF THE ESC GRADING. AND PERMITTED LANDFILL FACILITY. FACILITIES. C.STABILIZE SOILS AT THE END OF THE WORKDAY PRIOR TO A WEEKEND, HOLIDAY,OR PREDICTED RAIN EVENT. 19. CONTRACTOR SHALL VERIFY THE FEASIBILITY,OBTAIN AN INDUSTRIAL WASTE DISCHARGE 4. THE ESC FACILITIES ON INACTIVE SITES SHALL BE INSPECTED AND MAINTAINED AUTHORIZATION PERMIT AND SEEK APPROVAL FROM THE CITY OF RENTON UTILITY DISTRICT A MINIMUM OF ONCE A MONTH OR WITHIN 48 HOURS FOLLOWING A STORM EVENT. 5. WHERE SEEDING FOR TEMPORARY EROSION CONTROL IS USED,FAST GERMINATING PRIOR TO DISCHARGE OF ANY CONSTRUCTION RUNOFF TO THE SANITARY SEWER. GRASSES SHALL BE APPLIED AT AN APPROPRIATE RATE(EXAMPLE:ANNUAL OR S. TH ARE NOT ENGINEER MAINTAI MAINTAINED PROPERLY OR IF ATY TO HALT VIOLATION RAS NOT BEEN CORRECTED.CONSTRUCTION EROSION CONTROLS PERENNIAL RYE APPLIED AT APPROXIMATELY BO POUNDS PER ACRE). SEQUENCE OF CONSTRUCTION THE CONTRACTOR SHALL BEAR ALL RISK AND ALL COSTS OF ANY WORK DELAYS 6. WHERE STRAW MULCH IS USED FOR TEMPORARY EROSION CONTROL,IT SHALL BE THE TYPICAL CONSTRUCTION SEQUENCE SHALL BE AS FOLLOWS: CAUSED BY THESE ACTIONS. APPLIED AT A MINIMUM THICKNESS OF 2",AND BE CERTIFIED WEED FREE. A. CONDUCT PRE-CONSTRUCTION MEETING. 6. THE CONTRACTOR SHALL COMPLY THE NPDES PERMIT REQUIREMENTS MONITOR AND 7. ALL WORK AND MATERIALS SHALL BE IN ACCORDANCE WITH CITY OF RENTON B. POST SIGN WITH NAME AND PHONE NUMBER OF TESC SUPERVISOR. REPORT THE STORM WATER DISCHARGE IN ACCORDANCE WITH THE GENERAL PERMIT. STANDARDS AND SPECIFICATIONS. 7. FOR TURBIDITY NONCOMPLIANCE ISSUES,THE CONTRACTOR SHALL CONTACT 8. THE ESC FACILITIES SHALL BE CONSTRUCTED IN ACCORDANCE WITH THE DETAILS ON C. INSTALL CATCH BASIN INLET PROTECTION. DEPARTMENT OF ECOLOGY WATER QUALITY MANAGER. FOR SPILL OF IMMEDIATE THE APPROVED PLANS. LOCATIONS MAY BE MOVED TO SUIT FIELD CONDITIONS. DANGER TO LIFE AND HEALTH,THE CONTRACTOR SHALL CONTACT DEPARTMENT OF SUBJECT TO APPROVAL BY THE ENGINEER AND THE CITY OF RENTON INSPECTOR. D. INSTALL PERIMETER PROTECTION(HIGH VISIBILITY FENCE,ETC.). ECOLOGY HOT LINE(425-649-7000)AND CITY OF RENTON SPILL AND DISCHARGE 24-HOUR CONTACT 425-430-7400. E. CLEAR AND GRUB THE SITE. ( ) 9. A COPY OF THE APPROVED EROSION CONTROL PLANS MUST BE ON THE JOB SITE WHENEVER CONSTRUCTION IS IN PROGRESS. F. MAINTAIN EROSION CONTROL MEASURES IN ACCORDANCE WITH PLANS AND MANUFACTURER'S RECOMMENDATIONS. 10. CLEARING LIMITS SHALL BE DELINEATED WITH A HIGH VISIBILITY FENCE. G. EXCAVATE INFILTRATION FACILITY. It OFF-SITE STREETS MUST BE KEPT CLEAN AT ALL TIMES. IF DIRT OR MUD IS DEPOSITED ON THE PUBLIC STREET SYSTEM,THE STREET SHALL BE IMMEDIATELY H. INSTALL TREATMENT LINER. CLEANED WITH POWER SWEEPER OR OTHER EQUIPMENT. ALL VEHICLES SHALL LEAVE THE SITE BY WAY OF THE CONSTRUCTION ENTRANCE AND SHALL BE CLEANED OF ALL L INSTALL MINERAL AGGREGATE. DIRT THAT WOULD BE DEPOSITED ON THE PUBLIC STREETS. J. INSTALL NEW STORM DRAIN. K. INSTALL BIORETENTION CELLS. F L. RESTORE ROADWAY AND SIDEWALKS. k M. INSTALL IRRIGATION SYSTEM. 3 N. INSTALL PLANTS. 8 0. RELOCATE EROSION CONTROL MEASURES OR INSTALL NEW MEASURES SO THAT AS ACCORDANCEOWITH THE 6TYHTESC EROSION AND REQBIMEMENTSNTROL IS ALWAYS IN P. STABILIZE ALL AREAS THAT REACH FINAL GRADE WITHIN 7 DAYS. i Q. SEED ANY AREAS TO REMAIN UNWORKED FOR MORE THAN 30 DAYS. R. UPON COMPLETION OF THE PROJECT ALL DISTURBED AREAS MUST BE STABILIZED AND BEST MANAGEMENT PRACTICES AE APPLIED TO REMOVAL OF CONTROLS IF 9 APPROPRIATE. u �As Norco X.—T6 CITY OF 2/27/1s FOR APPRovu r, RENTON SUNSETTERRACE CH2MH I LL _ DATUM REGIONAL STORIAWATER FACILITY Pm i"/BNlama/P„mm A—II Q pt TESC GENERAL NOTES C-4 9 C. REVISION BY DATE APPR ^gym �'" 4 21 / r NOTES 1. THIS PLAN REFLECTS PRE—DEMOLITION CONDITIONS. DEMOLITION TO BE COMPLETED UNDER A SEPARATE CONTRACT r e r j BY THE CITY OF RENTON. DEMOLITION TO INCLUDE: EXISTING BUILDINGS r SIDEWALK h LANDSCAPE SURFACES ,I li EXISTING UTILITY SERVICES TO BE ABANDONED AND S = CAPPED AT PROPERTY LINES i SEE DEMOLITION SPECIFICATIONS FOR EXPECTED CONDITIONS. f / 2. DRAWINGC— SHOWS THE ANTICIPATED POST—DEMOLITION CONDITIONS. 1 iv AIL zv i a n , tt SCALE IN FEET AS NOTED CITY OF 2/2T/15 R CH2/� `� `a'O RENTON SUNSETTEATER MHILL _ �rUW REGIONAL STORMWATER FACILITY 9Y o _ Pk mg/B Idi,/P.ar Wg D,pt. EXISTING CONDITIONS PRIOR TO DEMOLITION E-1 yBV W1E APPR •w sr�. 5 21 SITE PREPARATION CONSTRUCTION NOTES :R e REMOVE EXISTING TREE $gyp I ElErINMI EX ROW ,1I \` �2 PROTECT EXISTING TREE �y ENO© 1i SEE 1{ NOTE 4 �3 SAV/CUT ANGLE POINT ,G APPROXIMATE REMOVAL LIMITS. a I REMOVE EXISTING CURB,GUTTER,SIDEWALK TO THE NEAREST s-- BEGIN© 3� O '" ;f � 6 �I�i EXPANSION JOINT,AS DIRECTED BY THE ENGINEER REMOVE EXISTING FENCE 3 ABANDON EXISTING UTILITY END© .T K REMOVE EXISTING CURB AND GUTTER t g } 3 •' ,%� I � } �7 REMOVE EXISTING DRAINAGE PIPE REMOVE EXISTING DRAINAGE STRUCTURE " �P .'T9EEOid© ENO© I -'j�_ 3 �9 PLUG EXISTING UTILITY PIPE END Y w = TESC CONSTRUCTION NOTES O CONSTRUCT I N 5 SEE NOTE 3 EX ROW r✓ O ENTRANCE h 1O INSTALL INLET PROTECTION AT EXISTING CATCH BASINS ( AND NEW CATCH BASINS,PER CITY OF RENTON STANDARD PLAN 216.80 O INSTALL STABILIZED CONSTRUCTION ENTRANCE,PER CITY OF ftENTON STANDARD PUN 215.10 5 I sEE NOTES NOTE T' ,.--" ..+'�� ,.'' "`l r• -+�+j - 1 PROTECT INFILTRATION FACILITY h BIORETENTION CELLS FROM CONSTRUCTION STORM WATER RUNOFF UNTIL SITE IS I FULLY STABLE 9 2. REMOVE/PLUG E SID SEWERS CONSTRUCT FACILITY OFFLINE 4."� llI—lI IlI ln�l y.� y I I r 1 j. t i B. _ I SANDTABLE. DO NOT INTRODUCE FLOWS UNTIL SITE IS FULLY IF 3. KING COUNTY LIBRARY CONSTRUCTION AREA.EXISTING BASEMAP FEATURES MAY BE ALTERED DUE TO NEW AND CONCURRENT CONSTRUCTION ACTIVITIES. 4. NEW UTILITIES TO BE CONSTRUCTED BY KING COUNTY v I tW 7 I LIBRARY. STOCKPILI AREA f - f `` NO 6 BEGIN r LEGEND 3 XXXXX)OO00000000L tx TO BE REMOVED w,'lF� �^/� ` bt�w'^v,` \, "/ 7j �'f \ 7� • • • • TO BE ABANDONED 7 \ .` REMOVE SAWCUT AND REMOVE EXISTING ASPHALT CONCRETE PAVEMENT AND CEMENT CONCRETE SIDEWALK O CONSTRUCTION ENTRANCE .t[ c b HIGH VISIBILITY FENCE cc 11 SILT FENCE PROTECTION FENCE Z 0_ `� ���f I f t `�\\ .r "`•�. - �� � r i,l —>--- SANDBAG BERM s (1 V yy \ K t Z SCALE IN FEET Q �,lS NOTED '�"T'�"' A 2/21/15 CITY OF Avvnovu ,� SUNSETTERRACE CH2MHILL — REN TON REGIONAL STORMWATER FACILITY r d DAiOM cla.smy/ewwlea/I=�er.won.o.p1. SITE PREPARATION AND TESC PLAN -1 N. R-SION BY M1E APPR ••� v�i�v o 0 SITE PLAN CONSTRUCTION NOTES f..7 1O INSTALL DRAINAGE PIPE }jy TEMPORARY CONSTRUCTION EASEMENT 1 O2 INSTALL DRAINAGE STRUCTURE P INSTALL CLEANOUT 4 ,1 I" © CONNECT TO EXISTING PIPE/STRUCTURE • .,� � -' E ROW r t 6 INSTALL FLOW SPUTTER C17 1 ' PLUG h ABANDON EXISTING STORM DRAIN PER WSDOT STANDARD PLAN 7-08.3. SEE ORAWING C-E FOR St_ N0, S '.t { '� PROFILE INSTALL OUTLET PROTECTIONe 4 C-g { m 4 1 (SEE NOT _� ' �.,,/"'•, � - .. x2-4 (SFF I. iF 2) fia 2 z 4 EX ROW 1 I F'\• ,:, EX ROW � ATCH LINE SUNSET LN N STA 63+20, SEE C-3 APPROXIMATE KING COUNTY) LIBRARY FOOTPRINT ------ SEE DRAWING C-5 UTILITIES TO BE INSTALLED 810RETENTION CELL I FOR PROFILE BY KING COUNTY LIBRARY (SEE DRAWING C-4) (SEE NOTE 4) NOTES: 1.CONTRACTOR TO PROTECT AND PROVIDE SUPPORT DURING CONSTRUCTION FOR ALL UTILITY CROSSINGS. 2.KING COUNTY LIBRARY CONSTRUCTION AREA.EXISTING BASEMAP FEATURES MAY BE ALTERED DUE TO NEW AND rn CONCURRENT CONSTRUCTION ACTIVITIES. m 355 i nr.sw 355 3.PIPE:7 LF 12"DIP O 22%. 4.INTERSECTION IMPROVEMENTS AT NE 10TH ST AND SUNSET m - LN NE ARE CURRENTLY UNDER CONSTRUCTION AS PART OF ¢ 4I THE LIBRARY PROJECT. ADDITIONAL IMPROVEMENTS TO BE 350 w zm $ E ISTING G OUND u 350 CONSTRUCTED AS PART OF THE LIBRARY PROJECT INCLUDE w _ THE 12"WATER MAIN AND INSTALLATION OF THE STORM m rc m o o a SYSTEM CONNECTING RUNOFF FROM THE LIBRARY TO THE m ww o l w _ CITY'S SYSTEM. 345Ti m4+a rc -; 3mrc_ w 345 m nnn 340 ~&W Q 1 32x 340 a 931.E 18' P Q 298 oEX. 335 5L 1. CPEP 335 S S { 330 330 z 5 eq tq a p �q .' 12+00 13+00 14+00 15+00 SCALE IN FEET 9 R FIRE—E.— Y SAS NOTED "�"'� .� S J2/27/15_® CITY OFFOR- 8"`� �R RENTON SUNSETTERRACECH2MHILL oATuu REGIONAL STO AND PROR FACILITY Planning/BagEinq/Public Woda oaPl. SITE PLANANUPROFILEN0. REVISION BY MTE — — 1 SITE PLAN CONSTRUCTION NOTES { \ 1 2 4-1 I INSTALL DRAINAGE PIPE ENTION CELL 1\ 111 DRAWING C-4) ( �� ) 7/ O2 INSTALL DRAINAGE STRUCTURE J 4-2 2 It i �_ O3 INSTALL CLEANOUi r i /// ATER METER 2 1 I,1 ® CONNECT TO EXISTING PIPE/STRUCTURE SEE NOTE 5 W INSTALL FLOW SPUTTER C17 ^ r ,SEE NOT PLUG @ABANDON EXISTING STORM DRAIN PER �.. F ASPHALT RAMP \� N �" r \ N 6 WSDOT STANDARD PLAN 7-08.3. �£ SEp OTE 4 ^°' „^ 'ASP PAIHIP 3-4 2 \ M O7 INSTALL OUTLET PROTECTION e fS r ! AT ROADWAY EVEL` - 0 C-8 c F �NOTE 2 4 3 7 ! 11 "" _ Q (SEE NOTE`2) I''"j / �, 1 1 i N 2 3t8 Ui ee T a 3 1 .. ..........._�.,� Z WATER SERVICE .' J --LINE 2 SEE NOTE 5 _I + 32 Ian z 2 3+00 62+00 OUTLET +00 - S-LINE I -..�y^ v 2 3=3 STRUCTURE lTT7 Z NT f, (( 1 I ''ggqq e•' Y UTILITY TO BE INSTALLED I I VLL,` BY KING COUNTY LIBRARY ,r N. KING COUNTY LIBRARY CONSTRUCTION AREA. SEE NOTE 3. NOTES: 1.CONTRACTOR TO PROTECT AND PROVIDE SUPPORT DURING r F r CONSTRUCTION FOR ALL UTILITY CROSSINGS. 2.THE LOCATION OF THE STRUCTURE IS APPROXIMATE. CONTRACTOR TO FIELD LOCATE EXISTING STORM DRAIN UNE z3 a» o AND INSTALL NEW STRUCTURE. ~ _y <Y�i o Vm n c 3.KING COUNTY LIBRARY CONSTRUCTION AREA.EXISTING BASEMAP FEATURES MAY BE ALTERED DUE TO NEW AND 345 x'C m -g ^ o i N �o- rvN� �0 345 CONCURRENT CONSTRUCTION ACTIVITIES. �m ww yd< ~ x 4.MATCH RESTORED WALKWAY TO EXISTING SIDEWALK WITH E%ISTI 1;LROUN -- -m'^'/' --'^ �rcw "-� 6'MIN HMA TRANSITION RAMP(8.0%MAX SLOPE). 340 4d 340 5.CONTRACTOR TO INSTALL NEW 2-WATER SERVICE LINE. SEE SPECIFICATION SECTION 7-15.-_ _! 3-w pul 6.EXTRUDED CURB PER WSDOT STANDARD F-10.42-00 WITH IEX W I2. mm 335 6'GAPS IN CURB FOR POSITIVE DRAINAGE. 335 E% W.. EX N 7.INSTALL 5 FEET OF NEW CONCRETE SIDEWALK PER WSDOT W 0 0 0 d nz STANDARD PLAN F-30.10-03. INSTALL NEW CONCRETE CURB Y .- AND GUTTER PAN PER WSDOT STANDARD F-10.16.00. 330 F i'CPEP O :38% 330 8.FOR DRAINAGE STRUCTURE 3-1,3-2,3-3,3-4,AND 3-8, a CPEP O 1 5% INSTALL MAXIMUM HEIGHT OF ADJUSTMENT RISER ALLOWED BY g 35 t20R� 8!f 12' THE STANDARD PLAN, 15LF 17 CPEP. 0 50% CPEP 1.20% 1 LF 12" 325 CPE m 1.07% 325 B.INTERSECTION IMPROVEMENTS AT NE LOTH ST AND SUNSET LN r NE ARE CURRENTLY UNDER CONSTRUCTION AS PART OF THE $ - LIBRARY PROJECT.ADDITIONAL IMPROVEMENTS TO BE CONSTRUCTED AS PART OF THE LIBRARY PROJECT INCLUDE THE 12-WATER MAIN AND INSTALLATION OF THE STORM 4 SYSTEM CONNECTING RUNOFF FROM THE LIBRARY TO THE CITY'S SYSTEM. 5 S za to a m 10 9 60+00 61+00 62+00 63+00 SCALE IN FEET aw°fPPr:"w°u 4 �As NDTED CITY OF s/zT/1s t°��"° 7� RENTON SUNSETTERRACE C H2M H I LL !VIATI _ DATUM REGIONAL STORMWATER FACILITY c � PI..OAR/8uBamy/Public Wen.,13 P1. SITE PLAN AND PROFILE .�C-3 APP6 -X. a�- B ]1 O O J s ' z a 4 p SITE PLAN CONSTRUCTION NOTES OI INSTALL DRAINAGE PIPE SEE NOTE 4 INSTALL DRAINAGE STRUCTURE ^- {"�-- .,; O INSTALL CLEANOUT 2 Sa\ CP20 .. .. CP24, / 4O CONNECT TO EXISTING PIPE/STRUCTURE k7 INSTALL FLOW SPLITTERe BOUNDARY F _ INFILTRATION GALLERY i \ C 7 O6 PLUG BABANDON EXISTING STORM GRAIN PER WSOOT STANDARD PUN 7 11.3 1 UNOERDRAIN BIORETENTION CELL 2 Cp6 1 f 2 !3 O7 INSTALL OUTLET PROTECTION C-8 7 a-3 2 ^ f {� EL /3 ELEV.®776.33 7 R3.4� CPS 1 (SEE NOTE 3 e � t 1 v 15EE NO E� _ -- NDERDRNN OI P4 - } 'G' P�F�1, S•_ - 12"PVC _ _ i C°� } 2 $' (SEE RAIN PIPE NOTE 7 �7 PRESETTLING AR_4 - 3_1 C-8 1 's __ -o ! CP18 P CP17 1 ii 7 �ti ANTI-SEEP 1�1 O 3-2 UNDERDRAIN 1 -`l (SEE NOTE 7 / COLLAR BLOC 1- N IO®3ELEV.3650 '-o 8",THICKIDE X _______ _ _, __ CP70 _ __ _ _ _________CP76_�2� ____ ___� _ NOTES: CP11 P12 CP13 CP15 1.CONTRACTOR TO PROTECT AND PROVIDE SUPPORT DURING LITY CONSTRUCTION 2-FOR CONTROL POINT(CP)TIS E DRAWING GC-7. 1 3 3 .L ____-_ ________�M _______ -----______ __ __ 3.CB 4-3,CB TYPE 2,48 IN WITH CIRCULAR FRAME CPl\ \ ! 3 ` \ ( � AND COVER '\ LOTH 11+90.90,78.30'RT. \ x'\ CP2 T. \\ 05 SEE DRAWING = 00 SEE NOTE 5 R RIM=EL 333.10 340. 4. SEE DRAWING C-5 FOR PROFILE. / \ 4-1 2 1 PROFLE Y ✓ �' \ OVERFLOW / \nr 5.ANTICIPATED FUTURE CURB LINE. STRUCTURE,. SEE NOTE/4 i ' j PLAN 301 0-30-30.INSTALL SIDEWALK PER DOT STANDARD RO NEW CONCRETE CURB AND \\ x 6 LA - 4-2 2 GUTTER PAN PER WSDOT STANDARD PLAN F-10 16-00. �RFLOWY I I y q 7-INSTALL 12"PVC DRAIN PIPE UNDERNEATH THE ROCK PAD yy YY UP TO 2 FEET BEYOND THE EDGE OF ROCK PAD. CT BOUNDARY OF INFIITR�TION'QALLERY, STRUCTURE, 0, �' \\\ \\ \ MINERAL AGGREGATE d E 26', /// SEE NOTE 4 t W �... OO WATER\ 2F \\ \ \\ / E METER(2") v. 1 X \\ t l z �\ Y I i U o U x \ SCALE IN FEET Z N �As NOTFo �_ .sue CITY OF g CH2MHILL " _ -7� RENJTO�J SUNSET TERRACE onruM REGIONAL STORMWATER FACILITY C �®• Planning/BuilEinq/Puplic woes oeol. SITE PLAN C-4 9 MR 9 21 NJ E%ITING GRO ND B RETENTI CELL 2 EXISTING ROUND.. BIORET NTION GE L1 B TTOM -336.33' QON 345 ,�._�x EXISTING GROUND 60TT0 ELEV 33.5' �� �' 345 �p I 336.5' 340 o s 340 285z 335 11TL I6`CPEP 0 0,45X EX G IBA CPEP.a 0. 335 EX:W:.- EX 54L 12 CPfP 2257.5 O 330 UNDERD RAIN - C 6 C 8 330 C C_e 325 UNDER IN 325 NOTES: - 1. CONTRACTOR SHALL PROTECT AND PROVIDE SUPPORT �. DURING CONSTRUCTION FOR ALL UTILITY CROSSINGS, EXi5TING GROUND 345n S .. ^ -.EXISTIN GROUND 345 810 ETENTION CELL 1 m�iin F�1 IE 3633' RO OM ELEV 3365' "' P 340 340 335 SLF 12'C EP.O 0.6 335 OEX 6" TORM DRAT .�.. g 2'UNDER RAIN G-8 330 LE n o 0." 330 z a X..12"SE R _ U 325 325 S r i Z 5 s a o 4i VERTICAL SCALE: 1 U 3 SCALE IN FEETOf LL m 10 a 4o HORIZONTAL SCALE: 9 SCALE IN FEET E ACITY OF 2/27/15 I� RENTON SLINSETTERRACECH2MH1LL DATUMREGIONAL STORMWATER FACILITY inDRAINAGE PROFILE C-5 A d'®' 10 21 SITE PLANTING.SEE DRAWING L-1 1 BIORETENTION PLANTING.SEE DRAWING L-1 SELECT BACKFILL EL 339.60' 80Ti0M ELEVATION 336.33' SELECT BACKFILL EL 33.66' 18"BIORETENTION APPROXIMATE EXCAVATION 11 ' 1 L 11 2"MULCH SOIL 1 r J 1 LIMITS OF SELECT BACKFILL 1 1 CONSTRUCTION 1 3 3 1 1 r GEOTEXTILE _____________ _____________________________ TO FOR UN N - DRAINAGE, I 36"MINERAL EL 331.83' 12"PVC SLOTTED 34"MINERAL GEOTEXTILE CLASS A,MODERA� AGGREGATE i� T� E��UNDERDRAIN, AGGREGATE I FOR UNDERGROUNO SURVIVABILITY I TYPE 2fi -SEE NOTE 1 TYPE 26 ORAINACE, CLASS A,MODERATE SURVIVABILITY CONTROL POINT ••.:.•_• .• ,'::• ••• EL:330.83' LEVEL BOTTOM 12"TREATMENT LAYER CONTROL POINT EL=330.83' EL=330.83' L 15' 15' 18, VARIES BIORETENTION CELL 2 SECTION SCALE:NTS C-4 SELECT BACKFILL CB 4-1 OVERFLOW STRUCTURE CONSTRUCTION WITH BEEHIVE GRATE GEOTEXTILE BOTTOM ELEVATION 336.50' (PROJECTED) FOR UNDERGROUND CS 3-2 CATCH BASIN SELECT flACKFlLL EL}}9.60' DRAINAGE TYPE 2 8"CLEANOUTZ* EL J37.00' (SEE DRAWING C-3) y 18"BIORETENTION SOIL y 1 I L 2"MULCH EL 334.83' 11 _ _ 2 - 0 1 3 J 1 1 r ANTI-SEEP _ e 8"PVC DRAIN PIPE F -- --- - _ ---� -- (SEE COLLENOTE 5) 12"X 8"REDUCER --- __ IE 333.28. .. .. > ..:..:'... 12"PVC viv AG MINERAL DRAIN PIPE CONTROL POINT UN PVC SLOTTED TYPE 24TE IE-332.7fi' EL=330.83' 0 0.3o RAIN PIPE TYPE 26 EL 331.83' LEVEL BOTTOM 12"TREATMENT DYER CONTROL POINT 5' 5' O 0.3 (SEE NOTE 1) E1=330.83' EL=330.8J' 5' 25' 12'PVC DRAIN PIPE q� 180, NOTES��11���� 3 : BIORETENTION CELL 1 1.UNDERDRAIN SHALL BE SLOTTED.PVC PIPE SCHEDULE 40. SLOT DIMENSIONS ARE 0.064"WIDE X 1.00"LONG SPACED SECTION B ALONC PIPE AT 3"ON CENTER.FOUR SLOTS PER RADIUS AT 40', 120%240'AND 320'. SCALE:NTS C-4 2.RIM OF OVERFLOW STRUCTURE TO BE 6 INCHES PROVE THE TOP OF MULCH. / 3.BEEHIVE CRATE SHALL BE OLYMPIC FOUNDRY MODEL SM600H. 4.CLEANOUT SHALL BE PER CITY OF RENTON STANDARD PLAN 403.1. y 5.ANTI-SEEP COLLAR SHALL BE FORMED WITH COF COLLAR.DIMENSIONS ARE 4'WIDE BY 8"THICK. 6.SEE SPECIAL PROVISION 2-03 FOR ADDITIONAL CONSTRUCTION REQUIREMENTS. 9 AS NOTED '_�'�'�"' CITY OFFOR I/IT/IS CH2MH I LL �smP° SUNSET COMMUNITYSTORM-SUNSET TERRACE C RENTON REGIONAL STOCTIONS RFACILITY DAiUM p N fiuilE PuElk Werkv Dapt. SECTIONS -6 y N0. REVISION CP'E APPR �•� vv> -I1 -21 RIM EL 341.71' MANHOLE RING MANHOLE RING AND INLET PIPE A AND COVER WITH COVER BOLTS,WITH LOCNING DRAIN" RIM EL 339.Go' LIFT HANDLE B" LOCKING BOLTS TOP OF RISER EL 339.00' HIGH FLOW BYPASS .'r•: S. I1 MA ---y` STEPS OR LADDER 4�"MIN ELBOW RESTRKTOR 78"0 TOP OF 18"DIA RISER TOP SLAB HIGH FLOW INLET PIPE B 1, H RISER EL 339.20' BYPASS // 6.0"DIA IE 337.44' ELBOW RESTRICTOR 6"MIN STEPS OR 7 7 4• WITH 5.6' ORIFICE337.37'. LADDER L _ DIA IE T"i�\ 1 INLET PIPE A II PIPE B B 1 / I INVERT EL 337.50 REATMENT FL INVERT EL 337.52 334 Al' 1 \ / 1 INVERT EL 337.00 18"DIA RISER /- - HI H F OW OVERFLOW ELEVATION T .... / INVERT EL 337.08 18"DIA 18"DIA REMOVABLE INLET FROM 1 COUPLER WATERTIGHT INFILTRATION GALLERY IE 332.70 1` PIPE SUPPORT TOP AND SOTTO COUPLING LET OF RISER 0 TLE' IN i TREATMENT RESTRICTOR PLATE RESTRICTOR PLATE OUTLET ELEVATION IE 332.41 FLOWS WITH ORIFICE,9.3"CIA WITH ORIFICE,6.3"DIA PIPE SUPPORT MORTAR(TYP) 0.0 ALUMINUM OR OR 0.07979"STEEL LB TYPE 2.72"DIA SHEAR GATE B"MIN DIA PLAN . SMOULDER BALLAST, FLOW 60" PER CITY OF N 237. RESTRICTOR(RISER) 6"THICK STANDARD PLAN 2}7.30 SHEAR GATE SOLID CAP 8"MIN CIA. 1.FLOW STANDARD SHALL CONFORM TO CITY SECTION OF RENTON STANDARD PLAN CONFORM TO EXCEPT AS SHOWN ON THIS DETAIL. SCALE:NTS B SHOULDER BALLAST, NOTES. 6"THICK 1.OUTLET STRUCTURE SHALL BE PER 2.SEE SECTION FOR STRUCTURE,RISER AND CITY OF RENTON STANDARD PUN ORIFICE SIZE AND ELEVATION. 237,00 EXCEPT AS SHOWN. 2"OVERLAY HMA CLASS 1/2" FLOW SPUTTER 2-2 n 4"HMA CL 1/2" OUTLET STRUCTURE 3-3 @ SCALE:NTS C-2 SAWCUT(IF WITHIN EXISTING PAVEMENT SCALE:NTS C-3 12" SECTION) TYP _ NOTES CONTROL POINTS TABLE POINT NORTHING EASRNG ELEVATION DESCRIPTION ;/\i/j i /\i 1. PIPE ZONE BEDDING AND BACKFILL FOR STORM SEWERS SHALL BE IN CPI 7&54113,27A4 1307011.5427 336.33 BIORETENTIONCELL280TTOM 6"CSBC ��/�/���/�/�/�`/,��/�/ BACKFILL MATERIALS SHALL BE ACCORDANCE WITH CITY OF STANDARD PUN 220.00"PIPE CP2 185409.8453 1307014.0883 33&33 BIORETENTION CELL 2 BOTTOM GRAVEL BORROW.OR CRUSHED ROCK COMPACTION DESIGN AND BACKFILCKFIL L". CP3 185396.2487 1307041.2336 336.33 BIORETENTON CELL BOTTOM COMPACTED TO 95%MAX DENSITY 2. FOR STORM SEWER INVERT DIAMETER,AND PIPE MATERIAL,SEE THE CP4 185393.7036 1307047.0706 336.33 BIORETENTION CELL 2 BOTTOM \ DRAINAGE PLANS AND PRO(:ILES. CPS 185394.5937 1307055.4212 336.33 RIORETENTION CELL 2 BOTTOM 3. FOR STORM SEWER CROSSING UNDER EXISTING WATER LINE,BACKFILL WITH CONTROLLED DENSITY FILL FROM TOP OF STORM SEWER PIPE TO CP6 185396.8184 1307056.9636 336.33 BIORETENTIONCELL2ROTTOM THE BOTTOM OF WATER LINE.BACKFILL WITH CONTROLLED DENSITY FILL STORM SEWER PIPE.SEE NOTE 2 FOR A TOTAL DISTANCE OF 6 FEET CENTERED ON THE WATER LINE. CP10 185365.5929 1307029.8139 336.50 BIORETENTION CELL I BOTTOM 4. FOR TYPICAL TRANSVERSE TRENCH IN THE ROADWAY,SEE CITY OF CPll 185360.9422 130]02&1751 336.50 BIORETENTIDNCELLIBOTTOM RENTON STANDARD PLAN H032.1. CP12 18535&7063 1307036.5434 33&50 ISIORETENTION CELL I BOTTOM GRAVEL BACKFILL FOR PIPE 5. ALL TRENCHES IN ROADWAY AREAS SHAH BE BACKFILLED AND CP33 1.85333.2523 1307068.4462 33&50 BIORETENTON CELLIBOTTOM ZONE BEDDING OR BEDDING TEMPORARY PATCHED WITH 2"MINIMUM HOT MIX ASPHALT AT THE END OF MATERIAL FOR FLEXIBLE PIPE, EACH WORK DAY. i CP14 185317.3678 1307070.8249 336.50 BIORETENTION CELLI BOTTOM SEE NOTE 1 y 6. FINAL PATCH SHALL BE INSTALLED WITHIN 2 WEEKS OF FINALINSPECTION. CPLB 185322.63M 1307087.1399 336.50 BIORETENTION CELL I BOTTOM CP16 185332.6418 1307079.5107 336.50 BIORETENTION CELLI BOTTOM =1=1�11 7. FOLLOWING THE COMPLETION OF STORM WATER,AND ALL RELATED IMPROVEMENTS,THE CONTRACTOR SHALL REMOVE ALL EXISTING ASPHALT ,L CP27 185351.4710 1307073.8585 336.50 BIORETENTION CELL I BOTTOM SUBSTANDARD SUBGRADE MATERIAL,AND REPLACE IT WITH 6"SURFACING 8RCP18 185359.9221 1307063.4220 336.50 BIORETENTION CELL I BOTTOM TOP COARSE AND 4"OF HOT MIX ASPHALT. 8 8. TRENCH WIDTH SHALL BE IN ACCORDANCE WITH THE SPECIFICATION 7P20 1854 11AE152 1307022.3175 33093 BOTTOM OF TREATMENT LAYER SECTION 2-09.4. i P121 ]853]8.8638 1306976.5590 330.83 BOTTOMOFTREATMENT LA22 7530&3 BOTTOMOFTIIEATMENTLAYERTYPICAL STORM SEWER TRENCH 23 2II_7 1307125.3381 330.83 B.TT.MOFTREATMENTLAYER 24 185407.3193 1307075.6348 330.83 ISOTTOM OF TREATMENT LAYER SECTION �31 SCALE:NTS C-2\�C-/ a a �k 2/z7/15 CITY OF SUNSET COMMUNITY-SUNSET TERRACE CH2MHILL • RENTON REGIONAL STORMWATER FACILITY �� wTUM Planning/Buileinq/P.eiK wow.,D.P1. DETAILS C-/ BY 9 N. REVISION BY MTE APPR +•� �`®�' 12 21 SEE TABLE A FOR DIMENSIONS(TYP) L1 L2 TABLE A:DIMENSIONS FOR ROCK PAD I PIPE DIAM L2 W L1 y� - 12" 5' 7' 6' 8 DITCH INVERT _ 18" 5' 7.5' 7.5' PLAN a' L2 M N BEVELED END 12"COBBLES SECTION SLOPE VARIES BIORETENTION D (M OPE) CELL BOTTOM \ SL rL PIPE AND DITCH W IF 2 LONGITUDINAL STRIPS OF GEOTEXTILE ARE REQUIRED,SEW SEAM INSTEAD OF OVERLAPPING COBBLES CONSTRUCTION GEOTEX7REQUIRED. PERMANENT EROSION C SEE:NTS - SCALE:NTS IF 2 LONGITUDIN GEOTEXTILE ARE SEAM INSTEAD O GEOTEXTILE FOR PERMANENT SECTION A EROSION CONTROL SCALE:NTS ROCK PAD AT OUTFAC ° 6"POND NG 15'X 7'I POOL WITH 2"MULCH E SCALE:NTS C-4 3 a 1 12* BID COBBLES SOIRETENTION CONSTRUCTION GEOTEXTILE FOR UNDERGROUND DRAINAGE,CLASS A MODERATE SURVIVABILITY 12"PVC DRAIN PIPE I"MINERAL AGGREGATE TYPE 26 e C-6 8 s 6 SECTION 12"TREATMENT LAYER iSCALE:NTS k nE�CM+Mervceo ey �..5. J-2/27/15NOTcu n CITY OFuRY cRENTON SUNSET COMMUNITY-SUNSET TERRACE CH2MHI ' wsuM REGIONAL STORMWATER FACILITY o.aDETAILS REVISION 8Y DATE APPR +� �^`®' f ; i 4 # 1 fH`T2'41a9 O. 48.' LT oTH 12+ o�t .QQ'LT \vv LEGEND 10TH 12 00 40.0 T i t W 9 t y RESTORE ASPHALT CONCRETE PAVEMENT I i 9 IOTH 12,840,9.5'LT RESTORE CEMENT CONCRETE SIDEWALK t .,1fEX � 1 TH12+ -_7.5 T -- ROW d r F t { _i j p {{ i 10TH 12+03.00 1 �LT ,� IOTH 15+0 ".0. RT 10TH 10+66 e6, 20,0'RT ,r._ I R=25 ✓�4� _. �4illt� 1 10TH 1'3+23.00 95'LT 10TH 14+6100'30'LT 10TH 13+2300 I OTH 12+03.00 0.0 LT t ..�,.. tOTH 12+63 0 L" .1- :...w .„„::.. .�L. 't OTH 12.6 1t.5' Ri t 10TH 10+92 09 20.0' R' `§. P R=25 y h � i6Y11 j 00.00 TH 13+5450 11.5' +" -��.. .� 'i 5.7 RTj t t W OTH 12+47,80 2C 0'RT ` 10TH 14+85 14 { 1 H R+!8.35, _._ .,0""t �EXROI E%RO q � lonl as 'k�ao'_Rr 21.1 Rr - LOTH 12+69.00 ATCH LINE SUNSET LN NE STA 63+20. SEE BELOW "7 20.0'RT ' t ZLN0+2�43. //SUNS LN 60+00.00, .0' LT �jSU40.0'LT % !SUNSE + "/ _N 61+39.40 30.0'LT \ N Y�Zt \ M N +44.70 SUN W 61+60.00 30.0'LT � \ h Z SUNSET.LN SUNSET LN 60+ CO. 14,5' RT Jw a _ SUNSET 1+6000 _ g 63+0 ~ 61+00 ? J f�/ SUNSET LN 62+30.00. 1 Z 0' lT u E l ET +41,30*^-T6.0 LT ¢ U A R SQI SET LN 60+23.73 11.7' LT SUNSET LN 60+23,73, 14.5' RT p �"`"' {I� C m to a zo au ti SCALE IN FEET Z J � Q CITY OF 2/_21/15 ~ u e°f°PPROOiLL '7� RENTON SUNSETTERRACE 00 CH2MHILL REGIONALSTORMWATERFACILITY _ �� wruu Piuc�IPo/a�aamy/P�mm wo.xe oePL PAVEMENT RESTORATION PLAN �.C-9 � 9 tr0. BY wTE O O WATER PLAN CONSTRUCTION NOTES Q1 CONNECT TO EXISTING MAIN WITH DI SLEEVES (MJ%MJ)WITH MECALUCS �x N Q2 INSTALL: 1 — 45 DECREE MJ BEND WITH MECALUCS 1 —THRUST BLOCK 1 r / PER CITY OF RENTON STANDARD PLAN 330.2 4' ^I 3 PION 33 GATE VALVE PER CITY OF RENTON STANDARD 2 0 RECONNECT SERVICE LINE,REPLACE GATE VALVE SCALE IN FEET M57ALL 8"X4"TEE WITH MECALUCS THRUST BLOCK PER CITY OF RENTON STANDARD PLAN 330.2 2 1�',/ ' 1T x oO f 2 y WATER PLAN GENERAL NOTES 1. ALL WORK MATERIAL SHALL BE IN CONFORMANCE WITH THE LATEST STANDARDS AND 7. ALL FITTINGS SHALL BE BLOCKED PER CITY OF RENTON STANDARD DETAILS UNLESS SPECIFICATIONS OF THE CITY OF RENTON PUBLIC WORKS DEPARTMENT AND THE 2008 OTHERWISE NOTED. EDITION OF THE WSOOT/APWA STANDARDS AND SPECIFICATIONS,AS APPROVED AND MODIFIED BY THE CITY OF RENTON IN THE RENTON STANDARD PLANS k SPECIFICATIONS. 8. THE CONTRACTOR SHALL NOT LEAVE STOCKPILED TRENCH EXCAVATION MATERIAL ON CITY SOME STANDARD DETAIL DRAWINGS MAY HAVE BEEN MODIFIED FOR THIS CONTRACT. THE STREETS OUTSIDE OF WORK HOURS. CONTRACTOR SHALL REFER TO DETAIL DRAWINGS INCLUDED IN THE CONTRACT DOCUMENTS. A SET OF APPROVED PLANS SHALL BE KEPT ON SITE AT ALL TIMES DURING B. THE CONTRACTOR SHALL USE A VACUUM STREET SWEEPER TO REMOVE DUST AND CONSTRUCTION. DEBRIS FROM PAVEMENT AREA AS DIRECTED BY THE ENGINEER. FLUSHING OF STREETS SHALL NOT BE PERMITTED. 2. ALL LOCATIONS OF EXISTING UTILITIES SHOWN ARE APPROXIMATE AND IT SHALL BE THE CONTRACTOR'S RESPONSIBILITY TO VERIFY THE TRUE AND CORRECT LOCATION SO AS TO 10. BEFORE COMMENCEMENT OF TRENCHING,THE CONTRACTOR SHALL PROVIDE A CATCH g AVOID DAMAGE OR DISTURBANCE. FOR UTILITY LOCATES CALL 800-424-5555(OR 811) BASIN FILTER FOR ALL DOWNHILL STORM DRAIN INLETS AND CATCH BASINS. THE 3 A MINIMUM OF 72 HOURS PRIOR TO EXCAVATION, CONTRACTOR SHALL PERIODICALLY INSPECT THE CONDITION OF ALL FILTERS AND d REPLACE AS NECESSARY. 3. AN APPROVED TRAFFIC CONTROL PUN IS REQUIRED TO BE SUBMITTED AT THE i PRE—CONSTRUCTION MEETING. ANY MODIFICATIONS TO THE APPROVED TRAFFIC CONTROL 11. PAVEMENT MARKINGS(E.G.LANE LINE BUTTONS OR PAINT,STOP BARS,CROSSWALKS, PUN SHALL BE RESUBMITTED AND APPROVED PRIOR TO IMPLEMENTATION. ETC.)DAMAGED OR REMOVED DURING CONSTRUCTION SHALL BE REPLACED IN KIND. U O 4. ALL NEW WATER PIPE AND FITTINGS SHALL HAVE A FOAM PIPE PIC RUN THROUGH THEM 12. TEMPORARY RESTORATION OF TRENCHES FOR OVERNIGHT USE SHALL BE ACCOMPLISHED 8R BEFORE BEING FLUSHED,DISINFECTED.AND PRESSURE TESTED. THE CONTRACTOR SHALL BY USING COLD MIX ASPHALT(HMA). STEEL PLATES MAY BE USED OVERNIGHT TO NOTIFY THE CITY OF RENTON WATER MAINTENANCE DEPARTMENT TWO WEEKS BEFORE COVER THE UST SECTION OF TRENCH. STEEL PLATES MUST BE PINNED DOWN AND MAKING A CUT—IN CONNECTION TO AN EXISTING WATER MAIN AND 5 DAYS BEFORE ASPHALT RAMPS/WEDGES MUST BE PLACED AROUND THE PLATES. STEEL PLATES SHALL Z 5 MAKING A CONNECTION TO A NEWLY CUT—IN TEE AND VALVE(S)ON THE EXISTING MAIN. NOT BE USED ON STEEP GRADES OR WHERE STEEL PLATES PRESENT A ROADWAY ALL PIPE AND FITTINGS NOT TO BE DISINFECTED IN PLACE SHALL BE SWABBED WITH 1% HAZARD. C.)i CHLORINE SOLUTION PRIOR TO INSTALLATION. 13. THE CONTRACTOR SHALL KEEP PROJECT AREA OPEN TO TRAFFIC AT ALL TIMES,UNLESS Of 5 5. AFTER DISINFECTING THE WATERMNN,DISPOSE OF CHLORINATED WATER BY DISCHARGING APPROVED BY THE CITY OF RENTON. TO THE NEAREST OPERATING SANITARY SEWER. 14, CONSTRUCTION WORK SHALL BE FROM 8:00 AM TO 4:00 PM. ' 6. DEFLECT THE COVER, 12 ABOVE OR BELOW EXISTING UTILITIES AS REQUIRED TO MAINTAIN 9 O3FTTHERWISE MINIMUM COVER, 12 IN. MINIMUM VERTICAL CLEARANCE BETWEEN UTILITIES UNLESS 15. ALL MECHANICAL JOINT FITTINGS AND VALVES SHALL HAVE MEGAIUG RETAINER GRANOS OTHERWISE SPECIFIED, IN ADDITION TO CONCRETE BLOCKING. 4 ® AS NDTFD '�"Sw 2/2)/15 NensoN o,.�.. CITY OF SUNSET TERRACE CH2MHILL to RENTON REGIONALSTORMWATERFACILITY r _ onruM Pmmm�g/eNllaloa/PNmm won.o.Pl. WATER PLAN ..W—) N0. BY WiE MPR �r 14 21