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Home My WebLink About16-029 TIR 5-5-2017Langston Properties Technical Information Report Job # 16-029 Table of Contents SECTION 1 PROJECT OVERVIEW ............................................................................................ 1-1 SECTION 2 CONDITIONS AND REQUIREMENTS SUMMARY ........................................... 2-11 SECTION 3 OFFSITE ANALYSIS ............................................................................................... 3-1 Task 1: Define and Map the Study Area ............................................................................................... 3-1 Task 2: Resource Review ...................................................................................................................... 3-1 Task 3 and Task 4: Field Inspection and Drainage System Description ............................................ 3-2 Onsite Basin ........................................................................................................................................... 3-2 Upstream Basin ...................................................................................................................................... 3-2 Existing Downstream Drainage Path..................................................................................................... 3-2 SECTION 4 FLOW CONTROL AND WATER QUALITY ANALYSIS AND DESIGN ......... 4-14 Hydraulic Model Analysis .................................................................................................................... 4-14 Existing Conditions .............................................................................................................................. 4-14 Developed Conditions ......................................................................................................................... 4-17 SECTION 5 CONVEYANCE SYSTEM ANALYSIS AND DESIGN........................................ 5-19 SECTION 6 SPECIAL REPORTS AND STUDIES .................................................................... 6-1 SECTION 7 OTHER PERMITS .................................................................................................... 7-1 SECTION 8 TESC ANALYSIS AND DESIGN ............................................................................ 8-1 SECTION 9 BOND QUANTITY WORKSHEET .......................................................................... 9-1 SECTION 10 OPERATIONS AND MAINTENANCE ................................................................. 10-1 Langston Properties Technical Information Report Job # 16-029 SECTION 1 Project Overview The proposed Langston Properties project is a 4-lot single-family boundary line adjustment and right-of-way improvement project located at 303 - 315 SW Langston Road, Renton, WA. More generally, the site is located in the SW ¼ of Section 18, Township 23 N, Range 5 E, W.M. Please refer to the Vicinity Map below. The project consists of five (5) existing parcels (King County Parcel Nos. 8663500-040, -045, -050, -060, - 065) totaling approximately 0.935-acres. The project will disturb approximately 0.196-acres of alley right-of- way for utility and access improvements. The alley runs east and west along the south side of the lots. The site is bordered by SW Langston Road to the north, a single-family residence to the east, an apartment complex to the south, and a single-family residence to the west. The site is occupied with four single family residences with associated out buildings, driveways, and utility services. Aside from the buildings and driveways, most of the remaining site area is landscape with lawn, shrubbery, and trees. Access to the residences is provided via four (4) individual connections to the southern side of SW Langston Road. The western most parcel has an additional gravel alley access to Stevens Avenue SW to the west. Onsite grades steeply slope from west to east at approximately 13%. A geotechnical analysis was performed by Terra Associates, Inc. and classified the soils as glacial till. There are no existing onsite drainage facilities. Stormwater generated onsite sheet flows and follows the existing topographical patterns. Langston Properties Technical Information Report Job # 16-029 Proposed development will remove the existing residences, associated structures and services. The project will dedicate 10-feet to the existing alley right-of-way and build a 20-foot wide alley that will serve as access for the existing thirteen parcels and have two connections to SW Langston Road. There are necessary utility improvements that include a water main extension through the alley, a section of sanitary sewer main replacement, and installing utility services for the twelve parcels. Stormwater elements will be designed in accordance with the 2009 King County Surface Water Design Manual (KCSWDM) as adopted and amended by the City of Renton 2010 Stormwater Design Manual (CORSWDM). The site is required to meet the Peak Rate Flow Control Standard (Existing Site Conditions) as indicated by the CORSWDM Flow Control Application Map. As such, the developed condition flows must match the 2-, 10-, and 100-year existing condition peak flow rates. With the proposed lot line adjustment and improvement related development the developed 100-year peak flow will not increase by more than 0.1-cfs. As such, the project meets the requirements of Exception #1 in section 1.2.3.1.A of the CORSWDM. Thus no flow control facilities are required and are not proposed. Details on the exception calculations are shown in Section 4 of this report. Langston Properties Technical Information Report Job # 16-029 The proposed project is also required to meet the Basic Water Quality treatment requirements. These are proposed to be met utilizing a premanufactured filter cartridge facility. Details on the water quality design and calculations are provided in Section 4 of this report. Langston Properties Technical Information Report Job # 16-029 SECTION 2 CONDITIONS AND REQUIREMENTS SUMMARY Compliance with core and special requirements as listed in Section 1.2 and 1.3 of the 2010 CORSWDM are listed below. The proposed project will consist of more than 5,000 sf of new and replaced impervious surface area and is therefore subject to Full Drainage Review. Core Requirement #1: Discharge at the Natural Location In the existing condition runoff sheet flows and interflows east and ultimately enters the public stormwater conveyance system in SW Langston Road and SR 900. The project proposes to capture onsite flows and tightline the flows to the same public conveyance system thus maintaining the same drainage pattern. Core Requirement #2: Off-site Analysis A Level I Downstream Analysis prepared by The Blueline Group is included in the Offsite Analysis and is provided in Section 3 of this report. Core Requirement #3: Flow Control The site is required to meet Peak Rate Flow Control Standard (Existing Site Conditions) as indicated by the CORSWDM Flow Control Application Map. The developed condition flows are required to match the 2-, 10-, and 100-year existing condition peak flow rates. However, the project proposes that the developed condition will have a less than 0.1-cfs increase to the existing 100-year flow rate. As such, the project will meet the 0.1-cfs flow rate exception More detail and supporting calculations are provided in Section 4 of this report. Core Requirement #4: Conveyance System The conveyance system is designed to convey the 25-year, 24-hour storm event without overtopping proposed and existing structures. Calculations are provided in Section 5 of this report. Core Requirement #5: Erosion and Sediment Control The temporary erosion and sedimentation control plan is shown in the Engineering Plans provided under separate cover. Section 8 describes in the detail the different BMPs used in the Engineering plans. Core Requirement #6: Operations and Maintenance An Operations and Maintenance manual is provided in Section 10 of this report. Core Requirement #7: Financial Guarantees and Liability A bond quantity worksheet is provided in Section 9 of this report. Langston Properties Technical Information Report Job # 16-029 Core Requirement #8: Water Quality The project is required to meet the Basic Water Quality treatment requirements. These are proposed to be met by utilizing a premanufactured filter cartridge facility and Filterra unit. More detail and supporting calculations are provided in Section 4 of this report. Special Requirement #1: Other Adopted Area-Specific Requirements: There are no known additional requirements for the subject project. Special Requirement #2: Floodplain/Floodway: The subject site does not contain or is not adjacent to any known flood hazard area. Special Requirement #3: Flood Protection Facilities: The subject site does not rely on an existing flood protection facility and will not modify or construct a new flood protection facility. This Special Requirement is therefore not applicable. Special Requirement #4: Source Control: The subject project is a residential development and not a commercial development. This Special Requirement is not applicable. Special Requirement #5: Oil Control: The subject project is a single family development and not a high-use development. This Special Requirement, therefore, is not applicable. Special Requirement #6: Aquifer Protection Area: The subject project is not located in an Aquifer Protection Area per the City of Renton Sensitive Areas map. Langston Properties Technical Information Report Job # 16-029 3-1 SECTION 3 OFFSITE ANALYSIS A Level I Downstream Analysis is included in this section. TASK 1: DEFINE AND MAP THE STUDY AREA A Downstream Drainage Exhibit and Downstream Drainage Photographs are included at the end of this section. TASK 2: RESOURCE REVIEW Available resource information (City of Renton GIS and King County iMap) was reviewed for existing or potential problems. The following is a summary of the findings from the information used in preparing this report.  The geotechnical report provided by Terra Associates, Inc. identifies soils as glacial till.  The site contains a single drainage basin that is a part of the Duwamish River Drainage Basin (City of Renton).  The site does not contain wetlands (City of Renton and KC iMap).  The site does not contain streams and is not located within a floodplain (City of Renton and KC iMap).  The site contains regulated slopes (City of Renton GIS).  The site is not within Landslide Hazard Zones (City of Renton, KC iMap).  The site is not located in a Seismic Hazard Area (City of Renton and KC iMap).  There were no drainage complaints filed with the city per City of Renton GIS Langston Properties Technical Information Report Job # 16-029 3-2 TASK 3 AND TASK 4: FIELD INSPECTION AND DRAINAGE SYSTEM DESCRIPTION A field inspection was conducted on Thursday June 16th, 2016, a sunny day with temperatures around 75°F. The field inspection included a review of the onsite basin, upstream basin, and downstream drainage investigation. The downstream investigation included verifying the flow path exiting the site up to a quarter mile. In addition, the investigation included identifying the discharge point into Duwamish river. Please reference the Downstream Drainage Exhibit, and Downstream Drainage Photographs included at the end of this section for further detail. ONSITE BASIN The project consists of five (5) parcels totaling approximately 1.06-acres along SW Langston Road. Additionally, there is an alley that runs east and west along the south side of the lots. The site is bordered by SW Langston Road to the north, a single family residence to the east, an apartment complex to the south, and a single family residence to the west. The site slopes west to east at an average slope of 13%. The site contains several vacant lots and several existing single-family residences as described in Section 1. There did not appear to be any existing onsite stormwater facilities. Stormwater runoff generated onsite sheet flows northeast following existing grades. Stormwater is eventually collected by the existing public storm system along the south side of SW Langston Road. Please refer to the photo exhibit on the following pages for further detail. UPSTREAM BASIN During the field inspection, it was determined based on topography and proximity to the project site that approximately 0.02 acres or area to the north and west is tributary to the site. The area consists primarily of lawn originating from neighboring residences. Stevens Ave to the west and SW Langston Road to the north have improved frontages with curb, thickened edge and subgrade stormwater facilities. Stormwater runoff generated in these areas are captured before reaching the site and are not tributary to onsite stormwater. EXISTING DOWNSTREAM DRAINAGE PATH Runoff from the site flows southeast along the south side of SW Langston Road through a series of catch basins for approximately 415 feet (Photos 4-6). The tight-line conveyance system is routed through the intersection of SW Langston Road and Sunset Boulevard and exits at the southwest corner of the intersection (Photos 7-10). The flow then crosses Hardie Ave SW and continues southwest. Approximately 470’ from the SW Langston Road and Sunset Boulevard, the flow crosses to the southern side of Hardie Ave Langston Properties Technical Information Report Job # 16-029 3-3 SW and continues southwest (Photos 11-12). Runoff turns south following the Hardie Ave SW curb line (Photos 15-16). The downstream analysis was terminated at the catch basin illustrated in Photo 18. The catch basin was approximately 1,550 feet from the property, just over the ¼ mile mark. Please refer to the Developed Conditions Exhibit in addition to the Downstream Drainage Exhibit and the Downstream Photo Exhibit included on the following pages. Langston Properties Technical Information Report Job # 16-029 3-5 Downstream Photo Exhibit Photo1 – Facing east approximately 60’ east from the intersection of SW Langston Road and Stevens Ave SW. Onsite conveyance will begin at a catch basin further downstream. Photo 2 – Facing east at northwestern edge of the property. Onsite conveyance will begin at a catch basin further downstream. Langston Properties Technical Information Report Job # 16-029 3-6 Photo 3 – Facing east at the intersection of Lind Ave SW and SW Langston Road. Onsite conveyance will begin at a catch basin further downstream. Photo 4 – Facing east approximately 220’ east of the intersection of Lind Ave SW and SW Langston Road. Onsite conveyance will be included from this catch basin on. Langston Properties Technical Information Report Job # 16-029 3-7 Photo 5 – Facing east approximately 325 feet east from the intersection of Lind Ave SW and SW Langston Road. Flow continues east towards Sunset Blvd (SR 900). Photo 6- Facing east approximately 415 feet east from the intersection of Lind Ave SW and SW Langston Road. Runoff continues east towards Sunset Blvd (SR 900). Langston Properties Technical Information Report Job # 16-029 3-8 Photo 7 – Facing northeast at the southwest corner of the intersection of Sunset Blvd and SW Langston Road. Flow approaches the catch basin from the west and conveys flow north towards a catch basin at the northeastern corner of the intersection. Photo 8 – Facing southwest at the northeast corner of the intersection of Sunset Blvd and SW Langston Road. Flow approaches from the southwest, enters the catch basin, and is routed south. Langston Properties Technical Information Report Job # 16-029 3-9 Photo 9 – Facing southwest at the southeast corner of the intersection of Sunset Blvd and SW Langston Road. Flow approaches from the north and is then routed southwest to the north side of Hardie Ave SW. Photo 10 – Facing southwest on the north side of Hardie Ave SW. Runoff continues southwest. Langston Properties Technical Information Report Job # 16-029 3-10 Photo 11 – Facing southwest approximately 200’ southwest of photo 10. Runoff is diverted southeast to cross over to the southern end of Hardie Ave SW. Photo 12 – Facing northwest approximately 50’ southeast of photo 11. Runoff continues southwest on the southern side of Hardie Ave SW. Langston Properties Technical Information Report Job # 16-029 3-11 Photo 13 – Facing southwest approximately 100’ southwest of photo 12. Hardie Ave SW curves southward. Runoff continues south. Photo 14 – Facing south approximately 90’ south of photo 13. Runoff continues south along Hardie Ave SW. Langston Properties Technical Information Report Job # 16-029 3-12 Photo 15 – Facing south approximately 90’ south of photo 14. Runoff continues south along Hardie Ave SW. Photo 16 – Facing south approximately 50’ south of photo 15. Runoff continues south along Hardie Ave SW. Langston Properties Technical Information Report Job # 16-029 3-13 Photo 17 – Facing southeast approximately 110’ south of photo 16 on eastern side of Hardie Ave SW. Runoff continues southeast. Photo 18 – Facing southeast approximately 150’ southeast of photo 17. Runoff continues southeast. The downstream investigation was terminated at the above catch basin. The above catch basin is just over a quarter mile from the project site. BLUELINE Langston Properties Technical Information Report Job # 16-029 3-16 SECTION 4 Flow Control and Water Quality Analysis and Design Stormwater elements are designed in accordance with the 2009 King County Surface Water Design Manual (KCSWDM) as adopted and amended by the City of Renton 2010 Stormwater Design Manual (CORSWDM). The site is required to meet the Peak Rate Flow Control Standard (Existing Site Conditions) as indicated by the CORSWDM Flow Control Application Map. As such, the flow control facility is sized to detain and release developed condition flows to match the 2-, 10-, and 100-year existing condition flow rates. The project is also required to meet the Basic Water Quality treatment requirements. HYDRAULIC MODEL ANALYSIS The drainage analysis was modeled using the King County Runoff Time Series (KCRTS) software. The Terra Associates, Inc. geotechnical report characterizes site soils as glacial till. See Geotech report in Section 6 of this Report. The site is located in the Seatac rainfall region with a location scale factor of 1.0. EXISTING CONDITIONS The existing basin boundary area is defined as that area that will be improved through development of the subject property as shown in the Existing Conditions Exhibit. The project boundary area is approximately 1.131 acres. The existing ground cover is developed with four houses with detached garages and landscaping. The land coverages used in the existing condition model is based on the measured areas provided by survey. The following information was used for generating time series and flow frequencies: Table 4.1 – Existing Condition Coverage Summary Total Area (AC) Forest Area (AC) Grass Area (AC) Impervious Area (AC) Total Area 1.131 0.000 0.803 0.328 Langston Properties Technical Information Report Job # 16-029 3-17 Figure 4.1 – Existing Condition Peak Flow Rates 25 CENTRAL WAY, SUITE 400,KIRKLAND,WA 98033P: 425.216.4051 F: 425.216.4052WWW.THEBLUELINEGROUP.COMBLUELINE Langston Properties Technical Information Report Job # 16-029 3-19 DEVELOPED CONDITIONS The developed basin boundary area, 1.131 acres, is equal to the existing basin boundary area. With the clearing of the houses the lots will remain cleared and undeveloped. The alley way will have a 20-foot wide, paved drive aisle and 5-foot wide concrete sidewalk. Additionally, the five lots are assumed to be developed. The City of Renton Municipal Code allows for a maximum impervious coverage of 65-percent. However, in order address single lot flow control BMPS the project will propose a reduced impervious foot print. An average maximum impervious area for the five lots will be 45.6-percent. These areas are shown in the Developed Conditions Exhibit. The table shown below summarizes the coverage areas that are proposed and are input into KCRTS. The following information was used for generating time series and flow frequencies using an hourly time step. Table 4.2 – Developed Condition Coverage Summary Total Area (AC) Forest Area (AC) Grass Area (AC) Impervious Area (AC) ROW 0.433 0.000 0.038 0.395 BLA Lots 0.698 0.000 0.380 0.318 Total Area 1.131 0.000 0.418 0.713 Figure 4.2 – Developed Condition Peak Flow Rates Because of the steep topography of the site, a portion of the alley is not able to be feasibly conveyed to the connection to the SW Langston Road. Per section 1.2.1 of the COR drainage manual, if the area produces not greater than 0.2 cfs a rock pad is an acceptable BMP to mitigate concentrated flow. As such, the project will provide a rock pad at the outlet of the conveyance system capturing this portion of the alley. Below is the KCRTS analysis for the area. Langston Properties Technical Information Report Job # 16-029 3-20 Figure 4.3 – Developed Condition Bypass Peak Flow Rates FLOW CONTROL EXEMPTION The calculations shown below analyze the increase in flow rate for the 100-year storm peak flow rate for the project. As this increase in flow is not more than the threshold difference of 0.1-cfs, the site is exempt from a flow control facility per Exception #1 in Section 1.2.3 in the 2009 KCSWDM with 2010 City of Renton Amendments. Onsite Predeveloped vs Onsite Developed – Flow Rate Analysis Predeveloped 100-year Flow Rate 0.325 cfs Developed 100-year Flow Rate 0.425 cfs Change in Flow Rate +0.100 cfs WATER QUALITY ANALYSIS AND DESIGN Water quality treatment will be accommodated with a prefabricated Filterra unit and a StormFilter cartridge filter unit. The facility will be designed according to the Basic Water Quality Menu. The sizing calculations are provided at the end of this section. 25 CENTRAL WAY, SUITE 400,KIRKLAND,WA 98033P: 425.216.4051 F: 425.216.4052WWW.THEBLUELINEGROUP.COMBLUELINE Size and Cost Estimate 11835 NE Glenn Widing Dr., Portland OR 97220 Toll-free: 800.548.4667 Fax: 800.561.1271 ©2015 Contech Engineered Solutions LLC www.conteches.com Page 1 of 1 Prepared by Mike Gillette on May 9, 2017 Langston Project – Stormwater Treatment System Renton, WA Information provided: • Presiding agency = City of Renton Information Provided: Structure ID Basin 1 Total basin area 1.11 ac Impervious area 0.33 ac Filterra model FTIB-G Outlet pipe size 6” Media bay dimensions 4’ x 4’ Total inside dimensions 6’ x 4’ Approximate Price $19,500 System Parameters: • Filterra Media Flow Rate = 100 in/hr • Treatment type = Basic • Depth Required from Rim to Outlet = At least 48” • Internal weir elevation = 3’ above outlet invert - Water will back up to this elevation before entering media bay. Size and Cost Estimate: The Filterra system for this site was sized using WWHM. Per the Department of Ecology approval, the total basin area, percent impervious area, and site location were used to size the system. Contech Engineered Solutions recommends using the Filterra Internal Bypass – Grate (FTIB-G) system to provide basic treatment. The estimated cost of this system is shown above, and this includes the complete system delivered to the job site. This estimate assumes that the system is delivered with all components pre-installed. The contractor is responsible for setting the Filterra and connecting all external plumbing. The Filterra Internal Bypass – Grate (FTIB-G) with standard weir height has an internal bypass capacity of 2.9 cfs. If the peak discharge from the drainage area is expected to exceed this rate, we recommend deepening the unit or utilizing an alternative configuration such as the Filterra – Standard Offline system with a downstream curb inlet structure. Size and Cost Estimate 11835 NE Glenn Widing Dr., Portland OR 97220 Toll-free: 800.548.4667 Fax: 800.561.1271 ©2012 Contech Engineered Solutions LLC www.conteches.com Page 1 of 1 TS-P027 Prepared by Mike Gillette on May 9, 2017 Langston Project – Stormwater Treatment System Renton, WA Information provided: • Presiding agency = City of Renton Structure ID Basin 2 Water Quality Flow Rate (cfs) 0.029 Peak Flow Rate (cfs) 0.073 Number of cartridges 2 Cartridge flow rate (gpm) 7.5 Media type ZPG Structure size Steel Catch Basin Approximate Price $10,000 Assumptions: • Media = ZPG cartridges • Cartridge flow rate = 7.5 gpm • Drop required from inlet to outlet = 2.3’ minimum Size and cost estimates: The StormFilter is a flow-based system, and is therefore sized by calculating the peak water quality flow rate associated with the design storm. The water quality flow rate was calculated by the consulting engineer using WWHM and was provided to Contech Engineered Solutions LLC for the purposes of developing this estimate. The StormFilter for this site was sized based on the above water quality flow rate. To accommodate this flow rate, Contech Engineered Solutions recommends using a (2) – 18” cartridge catch basin StormFilter. The estimated cost of this system is shown in the above table; this estimate includes a complete system delivered to the job site. The final system cost will depend on the actual depth of the units and whether extras like doors rather than castings are specified. The contractor is responsible for setting the catch basin StormFilter and all external plumbing. Typically the catch basin StormFilter has an internal bypass capacity of 1.0 cfs. Since the peak discharge is not expected to exceed this rate, a high-flow bypass upstream of the StormFilter system is not required. CONTECH Stormwater Solutions Inc. Engineer:MSG Date 5/9/2017 Site Information Basin 2 Project Name Langston Project Project State Washington Project Location Renton Drainage Area, Ad 0.062 ac Impervious Area, Ai 0.062 ac Pervious Area, Ap 0.00 % Impervious 100% Runoff Coefficient, Rc 0.95 Water quality flow 0.029 cfs Peak storm flow 0.073 cfs Filter System Filtration brand StormFilter Cartridge height 18 in Specific Flow Rate 1.00 gpm/ft2 Flow rate per cartridge 7.5 gpm SUMMARY Number of Cartridges 2 Determining Number of Cartridges for Flow Based Systems ©2006 CONTECH Stormwater Solutions contechstormwater.com 1 of 1 Langston Properties Technical Information Report Job # 16-029 5-21 SECTION 5 CONVEYANCE SYSTEM ANALYSIS AND DESIGN The conveyance system was designed to adequately convey the 25-year, 24-hour storm event with a minimum of 6-inches of freeboard in the onsite drainage facilities. A conveyance sheet was generated using the rational method to calculate flows for each area collected by each catch basin. See attached Catch Basin Sub-basin Map on the following pages. The precipitation rates for the 25-year, 24-hour storm event is 3.4 inches conservatively. The flows generated from the conveyance system spreadsheet for the storm event was input into a backwater analysis spreadsheet to confirm adequate sizing. The backwater analysis was performed to ensure that during the 25-year, 24-hour storm event, the headwater elevation in each structure will not be less than 6-inches from the rims. A weighted C value was used for each area collected by each catch basin. The average C value is based on the total area collected by the catch basins. Approximately 14.43-acres of upstream area is tributary to the proposed connection pipe in SW Langston Road. Based on the current condition of development, this area has approximately 4 dwelling units per acre and thus uses a C value of 0.48. During the 25-year storm, 24-hour storm event, all headwater elevations remained 6-inches below the rims. The system meets the requirements of the 2009 KCSWDM and therefore the conveyance system is adequately designed. RATIONAL METHOD CONVEYANCE SYSTEM DESIGN LOCATION:KING COUNTY PR (24-HR RAINFALL):3.4 INCHESPROJECT NAME: LANGSTON PROJECT NUMBER: 16-029 PREPARED BY: TMH DESIGN STORM: 25 YEARSUBBASINPIPE PIPE PIPE ACTUAL TRAVEL PIPE CAPACITY SUMMARYLOCATION AREA SUM OF TcIRQRMANNING'S SIZE SLOPE LENGTHVELOCITY (VR)TIME Q(FULL) V(FULL)QR/Q(FULL)FROM TO (AC) "C" (A * C) (A * C) (MIN) (IN/HR) (CFS) "n" (IN) (%) (FT) (FT/SEC) (MIN) (CFS) (FT/SEC) (%)CB 9 CB 8 0.177 0.75 0.133 0.133 6.30 2.73 0.363 0.012 12 0.600 45 2.53 0.30 2.990 3.81 12.1%CB 8 CB 7 0.061 0.90 0.055 0.188 6.60 2.65 0.498 0.012 12 8.640 143 6.86 0.35 11.345 14.45 4.4%CB 7 CB 6 0.086 0.90 0.077 0.265 6.94 2.57 0.680 0.012 12 11.820 86 8.53 0.17 13.270 16.90 5.1%CB 6 CB 4 0.055 0.90 0.050 0.315 7.11 2.53 0.795 0.012 12 0.500 40 2.97 0.22 2.729 3.47 29.1%CB 4 CB 2 0.560 0.70 0.392 0.707 6.30 2.73 1.932 0.012 12 0.500 106 3.75 0.47 2.729 3.47 70.8%CB 2 CB 1 14.426 0.48 6.924 7.631 6.30 2.73 8.442 0.012 18 0.600 83 5.69 0.24 8.815 4.99 95.8% BACKWATER CALCULATIONS PROJECT NAME:LANGSTONPREPARED BY:TMH PROJECT NUMBER:16-029DESIGN STORM:25 YEARENTRANCE ENTRANCE EXIT OUTLET INLET APPROACH BEND JUNCTIONPIPE PIPE MANNING'S OUTLET INLET PIPE FULL VELOCITY TAILWATER FRICTION HGL HEAD HEAD CONTROL CONTROL VELOCITY HEAD HEAD HEADWATER RIMFROM TO Q LENGTH SIZE "n" ELEVATION ELEVATION AREA VELOCITY HEAD ELEVATION LOSS ELEVATION LOSS LOSS ELEVATION ELEVATION HEAD LOSS LOSS ELEVATION ELEVATION FREEBOARDCB CB (CFS) (FT) (IN) VALUE (FT) (FT) (SQ FT) (FT/SEC) (FT) (FT) (FT) (FT) (FT) (FT) (FT) (FT) (FT) (FT) (FT) (FT)(FT)(FT)CB 1 CB 2 8.44 90 18 0.012 84.42 84.96 1.77 4.78 0.35 85.42 0.49 86.46 0.18 0.35 86.99 86.870.02 0.47 0.0687.5197.80 10.29CB 2 CB 4 1.93 106 12 0.012 85.46 85.99 0.79 2.46 0.09 87.51 0.26 87.77 0.05 0.09 87.91 86.990.02 0.00 0.0087.9093.936.03CB 4 CB 6 0.80 89 12 0.012 88.91 89.11 0.79 1.01 0.02 87.90 0.04 90.11 0.01 0.02 90.13 90.110.01 0.02 0.0090.1491.851.71CB 6 CB 7 0.68 86 12 0.012 89.11 99.31 0.79 0.87 0.01 90.14 0.03 100.31 0.01 0.01 100.33 100.310.01 0.00 0.00 100.32103.082.76CB 7 CB 8 0.50 143 12 0.012 99.31 111.67 0.79 0.63 0.01 100.32 0.02 112.67 0.00 0.01 112.68 112.670.00 0.01 0.00 112.68116.553.87CB 8 CB 9 0.36 45 12 0.012 111.67 111.94 0.79 0.46 0.00 112.68 0.00 112.94 0.00 0.00 112.94 112.940.00 0.00 0.00 112.95116.923.97PIPESEGMENT Langston Properties Technical Information Report Job # 16-029 6-1 SECTION 6 SPECIAL REPORTS AND STUDIES Geotechnical Report dated September 7, 2016 by Terra Associates, Inc. on the following pages. SITE Environmental Earth Sciences Terra Associates, Inc. Consultants in Geotechnical Engineering Geology and Figure 1Date SEPT 2016 VICINITY MAP RENTON, WASHINGTON LANGSTON Proj. No.T-7492 0 2000 4000 APPROXIMATE SCALE IN FEET REFERENCE: http://www.wsdot.wa.gov/data/tools/geoportal/ACCESSED 8/30/16 118ROW 48234567191012ROW 59TP-6TP-3TP-5TP-7TP-4TP-1TP-2REFERENCE:REFERENCE ONLY AND SHOULD NOT BE USED FORDESIGN OR CONSTRUCTION PURPOSES.DIMENSIONS ARE APPROXIMATE. IT IS INTENDED FORNOTE:THIS SITE PLAN IS SCHEMATIC. ALL LOCATIONS ANDConsultants in Geotechnical EngineeringTerraAssociates, Inc.Geology andEnvironmental Earth SciencesProj. No.T-7492LANGSTONRENTON, WASHINGTONEXPLORATION LOCATION PLANDate SEPT 2016Figure 2LEGEND:04080APPROXIMATE SCALE IN FEETSITE PLAN PROVIDED BY CLIENT.APPROXIMATE TEST PIT LOCATION Environmental Earth Sciences Terra Associates, Inc. Consultants in Geotechnical Engineering Geology and MAJOR DIVISIONS LETTER SYMBOL TYPICAL DESCRIPTION GRAVELS More than 50% of coarse fraction is larger than No. 4 sieve Clean Gravels (less than 5% fines) GW Well-graded gravels, gravel-sand mixtures, little or no fines. GP Poorly-graded gravels, gravel-sand mixtures, little or no fines. Gravels with fines GM Silty gravels, gravel-sand-silt mixtures, non-plastic fines. GC Clayey gravels, gravel-sand-clay mixtures, plastic fines. SANDS More than 50% of coarse fraction is smaller than No. 4 sieve Clean Sands (less than 5% fines) SW Well-graded sands, sands with gravel, little or no fines. SP Poorly-graded sands, sands with gravel, little or no fines. Sands with fines SM Silty sands, sand-silt mixtures, non-plastic fines. SC Clayey sands, sand-clay mixtures, plastic fines. SILTS AND CLAYS Liquid Limit is less than 50% ML Inorganic silts, rock flour, clayey silts with slight plasticity. CL Inorganic clays of low to medium plasticity. (Lean clay) OL Organic silts and organic clays of low plasticity. SILTS AND CLAYS Liquid Limit is greater than 50% MH Inorganic silts, elastic. CH Inorganic clays of high plasticity. (Fat clay) OH Organic clays of high plasticity. HIGHLY ORGANIC SOILS PT Peat.COARSE GRAINED SOILSMore than 50% material largerthan No. 200 sieve sizeFINE GRAINED SOILSMore than 50% material smallerthan No. 200 sieve sizeDEFINITION OF TERMS AND SYMBOLS COHESIONLESSCOHESIVE Standard Penetration Density Resistance in Blows/Foot Very Loose 0-4 Loose 4-10 Medium Dense 10-30 Dense 30-50 Very Dense >50 Standard Penetration Consistancy Resistance in Blows/Foot Very Soft 0-2 Soft 2-4 Medium Stiff 4-8 Stiff 8-16 Very Stiff 16-32 Hard >32 2" OUTSIDE DIAMETER SPILT SPOON SAMPLER 2.4" INSIDE DIAMETER RING SAMPLER OR SHELBY TUBE SAMPLER WATER LEVEL (Date) Tr TORVANE READINGS, tsf Pp PENETROMETER READING, tsf DD DRY DENSITY, pounds per cubic foot LL LIQUID LIMIT, percent PI PLASTIC INDEX N STANDARD PENETRATION, blows per foot Proj. No.T-7492 LANGSTON RENTON, WASHINGTON UNIFIED SOIL CLASSIFICATION SYSTEM Date SEPT 2016 Figure A-1 Langston Properties Technical Information Report Job # 16-029 7-1 SECTION 7 OTHER PERMITS No other permits are known to be required at this time. Langston Properties Technical Information Report 16-029 8-1 SECTION 8 TESC Analysis and Design The temporary erosion and sedimentation control plan is designed to reduce the discharge of sediment-laden runoff from the site. The plan is comprised of temporary measures (rock entrance, filter fence, straw mulch, etc.) as well as permanent measures (hydroseeding and landscaping). The following BMPs will be applied to prevent erosion and trap sediments within the project site and are shown on sheet TP-01:  Mark Clearing Limits / Minimize Clearing – Prior to any site clearing or grading, the clearing limits as noted on sheet TP-01 are to be marked in the field. The trees to remain will have tree protection measures installed per details on sheets TD-01.  Minimize Sediment Tracked Offsite – A stabilized construction entrance shall be installed as the first step in clearing and grading. The construction entrance is to be installed per detail on TD-01 and at the location shown on sheet TP-01.  Control Sediment – Perimeter protection to filter sediment from sheetwash shall be located downslope of all disturbed areas and shall be installed prior to upslope grading. The silt fence will be installed along the boundary of the site to retain all sediment on site, as shown on sheet TP-01. Additionally, storm drain inlet protection measures will be applied to all catch basins within the project vicinity. See sheet TP-01 for more details.  Stabilize Exposed Soils – Temporary and permanent cover measures shall be provided to protect all disturbed areas. Cover measures include the use of surface roughening, mulch, erosion control nets and blankets, plastic covering, seeding, and sodding. See sheet TD-01 for more details.  Control Runoff– Surface runoff generated onsite during construction will be captured by an interceptor ditch with check dams or silt fences as shown on TP-01. Runoff captured by the interceptor ditch will be conveyed to a sediment trap equipped with a flow control riser that will release controlled flows to the proposed stormwater infrastructure as shown on TP-01.  Control Dewatering– Any runoff generated by dewatering shall be treated by releasing the water to a well vegetated, gently sloping area. See notes on sheet TD-01. Langston Properties Technical Information Report 16-029 8-2  Control Other Pollutants – Pollutants shall be controlled per TESC notes shown on sheet TD- 01.  Final Stabilization – Prior to final construction approval, the project site shall be stabilized to prevent sediment-laden water from leaving the site after project completion. All disturbed areas shall be vegetated or otherwise permanently stabilized. See sheet TD-01 for more detail. Langston Properties Technical Information Report 16-029 9-1 SECTION 9 BOND QUANTITY WORKSHEET A City of Renton bond quantity worksheet is provided on the following pages. CED Permit #:U‐16006774UnitReference #PriceUnitQuantity CostBackfill & compaction‐embankmentESC‐16.50$ CYCheck dams, 4" minus rockESC‐2SWDM 5.4.6.380.00$ Each7560.00Catch Basin ProtectionESC‐335.50$ Each9319.50Crushed surfacing 1 1/4" minusESC‐4WSDOT 9‐03.9(3)95.00$ CYDitchingESC‐59.00$ CYExcavation‐bulkESC‐62.00$ CYFence, siltESC‐7SWDM 5.4.3.11.50$ LF11241,686.00Fence, Temporary (NGPE)ESC‐81.50$ LFGeotextile FabricESC‐92.50$ SYHay Bale Silt TrapESC‐100.50$ EachHydroseedingESC‐11SWDM 5.4.2.40.80$ SY261208.80Interceptor Swale / DikeESC‐121.00$ LF270270.00Jute MeshESC‐13SWDM 5.4.2.23.50$ SYLevel SpreaderESC‐141.75$ LFMulch, by hand, straw, 3" deepESC‐15SWDM 5.4.2.12.50$ SYMulch, by machine, straw, 2" deepESC‐16SWDM 5.4.2.12.00$ SYPiping, temporary, CPP, 6"ESC‐1712.00$ LFPiping, temporary, CPP, 8"ESC‐1814.00$ LFPiping, temporary, CPP, 12"ESC‐1918.00$ LFPlastic covering, 6mm thick, sandbaggedESC‐20SWDM 5.4.2.34.00$ SYRip Rap, machine placed; slopesESC‐21WSDOT 9‐13.1(2)45.00$ CYRock Construction Entrance, 50'x15'x1'ESC‐22SWDM 5.4.4.11,800.00$ EachRock Construction Entrance, 100'x15'x1'ESC‐23SWDM 5.4.4.13,200.00$ Each13,200.00Sediment pond riser assemblyESC‐24SWDM 5.4.5.22,200.00$ Each12,200.00Sediment trap, 5' high berm ESC‐25SWDM 5.4.5.119.00$ LFSed. trap, 5' high, riprapped spillway berm section ESC‐26SWDM 5.4.5.170.00$ LFSeeding, by handESC‐27SWDM 5.4.2.41.00$ SYSodding, 1" deep, level groundESC‐28SWDM 5.4.2.58.00$ SYSodding, 1" deep, sloped groundESC‐29SWDM 5.4.2.510.00$ SYTESC SupervisorESC‐30110.00$ HRWater truck, dust controlESC‐31SWDM 5.4.7140.00$ HRUnitReference #PriceUnitQuantity CostEROSION/SEDIMENT SUBTOTAL:8,444.30SALES TAX @ 9.5%802.21EROSION/SEDIMENT TOTAL:9,246.51(A)SITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR EROSION & SEDIMENT CONTROLDescriptionNo.(A)WRITE‐IN‐ITEMS Page 3 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.a EROSION_CONTROLUnit Prices Updated: 06/14/2016Version: 06/14/2016Printed 5/9/2017 CED Permit #:U‐16006774ExistingFuture PublicPrivateRight‐of‐WayImprovementsImprovements(D)(E)DescriptionNo. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Quant. CostGENERAL ITEMS Backfill & Compaction‐ embankmentGI‐16.00$ CYBackfill & Compaction‐ trenchGI‐29.00$ CYClear/Remove Brush, by hand (SY)GI‐31.00$ SYBollards ‐ fixedGI‐4 240.74$ EachBollards ‐ removableGI‐5 452.34$ EachClearing/Grubbing/Tree RemovalGI‐6 10,000.00$ AcreExcavation ‐ bulkGI‐72.00$ CYExcavation ‐ TrenchGI‐85.00$ CYFencing, cedar, 6' highGI‐9 20.00$ LFFencing, chain link, 4'GI‐10 38.31$ LFFencing, chain link, vinyl coated, 6' highGI‐11 20.00$ LFFencing, chain link, gate, vinyl coated, 20' GI‐12 1,400.00$ EachFill & compact ‐ common barrowGI‐13 25.00$ CYFill & compact ‐ gravel baseGI‐14 27.00$ CYFill & compact ‐ screened topsoilGI‐15 39.00$ CYGabion, 12" deep, stone filled mesh GI‐16 65.00$ SYGabion, 18" deep, stone filled mesh GI‐17 90.00$ SYGabion, 36" deep, stone filled meshGI‐18 150.00$ SYGrading, fine, by handGI‐19 2.50$ SYGrading, fine, with graderGI‐20 2.00$ SYMonuments, 3' LongGI‐21 250.00$ EachSensitive Areas SignGI‐22 7.00$ EachSodding, 1" deep, sloped groundGI‐23 8.00$ SYSurveying, line & gradeGI‐24 850.00$ Day1850.00Surveying, lot location/linesGI‐25 1,800.00$ AcreTopsoil Type A (imported)GI‐26 28.50$ CYTraffic control crew ( 2 flaggers )GI‐27 120.00$ HRTrail, 4" chipped woodGI‐28 8.00$ SYTrail, 4" crushed cinderGI‐29 9.00$ SYTrail, 4" top courseGI‐30 12.00$ SYConduit, 2"GI‐31 5.00$ LFWall, retaining, concreteGI‐32 55.00$ SFWall, rockeryGI‐33 15.00$ SF29435.00SUBTOTAL THIS PAGE:435.00850.00(B)(C)(D)(E)SITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR STREET AND SITE IMPROVEMENTSQuantity Remaining (Bond Reduction) (B)(C)Page 4 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.b TRANSPORTATIONUnit Prices Updated: 06/14/2016Version: 06/14/2016Printed 5/9/2017 CED Permit #:U‐16006774ExistingFuture PublicPrivateRight‐of‐WayImprovementsImprovements(D)(E)DescriptionNo. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Quant. CostSITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR STREET AND SITE IMPROVEMENTSQuantity Remaining (Bond Reduction) (B)(C)ROAD IMPROVEMENT/PAVEMENT/SURFACINGAC Grinding, 4' wide machine < 1000syRI‐1 30.00$ SYAC Grinding, 4' wide machine 1000‐2000sy RI‐2 16.00$ SYAC Grinding, 4' wide machine > 2000syRI‐3 10.00$ SYAC Removal/DisposalRI‐4 35.00$ SYBarricade, Type III ( Permanent )RI‐5 56.00$ LFGuard RailRI‐6 30.00$ LFCurb & Gutter, rolledRI‐7 17.00$ LFCurb & Gutter, verticalRI‐8 12.50$ LF6588,225.00Curb and Gutter, demolition and disposal RI‐9 18.00$ LFCurb, extruded asphaltRI‐10 5.50$ LFCurb, extruded concreteRI‐11 7.00$ LFSawcut, asphalt, 3" depthRI‐12 1.85$ LFSawcut, concrete, per 1" depthRI‐13 3.00$ LFSealant, asphaltRI‐14 2.00$ LFShoulder, gravel, 4" thickRI‐15 15.00$ SYSidewalk, 4" thickRI‐16 38.00$ SY34913,262.00Sidewalk, 4" thick, demolition and disposal RI‐17 32.00$ SYSidewalk, 5" thickRI‐18 41.00$ SYSidewalk, 5" thick, demolition and disposal RI‐19 40.00$ SYSign, Handicap RI‐20 85.00$ EachStriping, per stallRI‐21 7.00$ EachStriping, thermoplastic, ( for crosswalk )RI‐22 3.00$ SFStriping, 4" reflectorized lineRI‐23 0.50$ LFAdditional 2.5" Crushed SurfacingRI‐24 3.60$ SYHMA 1/2" Overlay 1.5" RI‐25 14.00$ SYHMA 1/2" Overlay 2"RI‐26 18.00$ SYHMA Road, 2", 4" rock, First 2500 SYRI‐27 28.00$ SY148841,664.00HMA Road, 2", 4" rock, Qty. over 2500SY RI‐28 21.00$ SYHMA Road, 4", 6" rock, First 2500 SYRI‐29 45.00$ SYHMA Road, 4", 6" rock, Qty. over 2500 SY RI‐30 37.00$ SYHMA Road, 4", 4.5" ATBRI‐31 38.00$ SYGravel Road, 4" rock, First 2500 SYRI‐32 15.00$ SYGravel Road, 4" rock, Qty. over 2500 SYRI‐33 10.00$ SYThickened EdgeRI‐34 8.60$ LF40344.00SUBTOTAL THIS PAGE:63,495.00(B)(C)(D)(E)Page 5 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.b TRANSPORTATIONUnit Prices Updated: 06/14/2016Version: 06/14/2016Printed 5/9/2017 CED Permit #:U‐16006774ExistingFuture PublicPrivateRight‐of‐WayImprovementsImprovements(D)(E)DescriptionNo. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Quant. CostSITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR STREET AND SITE IMPROVEMENTSQuantity Remaining (Bond Reduction) (B)(C)PARKING LOT SURFACING No.2" AC, 2" top course rock & 4" borrowPL‐1 21.00$ SY2" AC, 1.5" top course & 2.5" base course PL‐2 28.00$ SY4" select borrowPL‐35.00$ SY1.5" top course rock & 2.5" base coursePL‐4 14.00$ SYSUBTOTAL PARKING LOT SURFACING:(B)(C)(D)(E)LANDSCAPING & VEGETATION No.Street TreesLA‐1Median LandscapingLA‐2Right‐of‐Way LandscapingLA‐3Wetland LandscapingLA‐4SUBTOTAL LANDSCAPING & VEGETATION:(B)(C)(D)(E)TRAFFIC & LIGHTING No.SignsTR‐1Street Light System ( # of Poles)TR‐2Traffic SignalTR‐3Traffic Signal ModificationTR‐4SUBTOTAL TRAFFIC & LIGHTING:(B)(C)(D)(E)WRITE‐IN‐ITEMSSUBTOTAL WRITE‐IN ITEMS:STREET AND SITE IMPROVEMENTS SUBTOTAL:435.0064,345.00SALES TAX @ 9.5%41.336,112.78STREET AND SITE IMPROVEMENTS TOTAL:476.3370,457.78(B)(C)(D)(E)Page 6 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.b TRANSPORTATIONUnit Prices Updated: 06/14/2016Version: 06/14/2016Printed 5/9/2017 CED Permit #:U‐16006774ExistingFuture PublicPrivateRight‐of‐WayImprovementsImprovements(D)(E)DescriptionNo. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Quant. CostDRAINAGE (CPE = Corrugated Polyethylene Pipe, N12 or Equivalent) For Culvert prices, Average of 4' cover was assumed. Assume perforated PVC is same price as solid pipe.) Access Road, R/D D‐1 26.00$ SY* (CBs include frame and lid)Beehive D‐2 90.00$ EachThrough‐curb Inlet Framework D‐3 400.00$ EachCB Type ID‐4 1,500.00$ Each 11,500.0046,000.00CB Type IL D‐5 1,750.00$ EachCB Type II, 48" diameter D‐6 2,300.00$ Each 12,300.00 for additional depth over 4' D‐7 480.00$ FTCB Type II, 54" diameterD‐8 2,500.00$ Each for additional depth over 4'D‐9 495.00$ FTCB Type II, 60" diameterD‐10 2,800.00$ Each for additional depth over 4'D‐11 600.00$ FTCB Type II, 72" diameterD‐12 6,000.00$ Each for additional depth over 4'D‐13 850.00$ FTCB Type II, 96" diameterD‐14 14,000.00$ Each 114,000.00 for additional depth over 4' D‐15 925.00$ FTTrash Rack, 12" D‐16 350.00$ EachTrash Rack, 15" D‐17 410.00$ EachTrash Rack, 18" D‐18 480.00$ EachTrash Rack, 21" D‐19 550.00$ EachCleanout, PVC, 4" D‐20 150.00$ EachCleanout, PVC, 6" D‐21 170.00$ Each 132,210.00Cleanout, PVC, 8" D‐22 200.00$ EachCulvert, PVC, 4" (Not allowed in ROW)D‐23 10.00$ LFCulvert, PVC, 6" (Not allowed in ROW)D‐24 13.00$ LF 3694,797.00Culvert, PVC, 8" (Not allowed in ROW)D‐25 15.00$ LFCulvert, PVC, 12" (Not allowed in ROW)D‐26 23.00$ LFCulvert, PVC, 15" (Not allowed in ROW)D‐27 35.00$ LFCulvert, PVC, 18" (Not allowed in ROW)D‐28 41.00$ LFCulvert, PVC, 24" (Not allowed in ROW)D‐29 56.00$ LFCulvert, PVC, 30" (Not allowed in ROW)D‐30 78.00$ LFCulvert, PVC, 36" (Not allowed in ROW)D‐31 130.00$ LFCulvert, CMP, 8" D‐32 19.00$ LFCulvert, CMP, 12" D‐33 29.00$ LFSUBTOTAL THIS PAGE:17,800.00 6,000.00 7,007.00(B)(C)(D)(E)SITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR DRAINAGE AND STORMWATER FACILITIESQuantity Remaining (Bond Reduction) (B)(C)Page 7 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.c DRAINAGEUnit Prices Updated: 06/14/2016Version: 06/14/2016Printed 5/9/2017 CED Permit #:U‐16006774ExistingFuture PublicPrivateRight‐of‐WayImprovementsImprovements(D)(E)DescriptionNo. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Quant. CostSITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR DRAINAGE AND STORMWATER FACILITIESQuantity Remaining (Bond Reduction) (B)(C)DRAINAGE (Continued)Culvert, CMP, 15" D‐34 35.00$ LFCulvert, CMP, 18" D‐35 41.00$ LFCulvert, CMP, 24" D‐36 56.00$ LFCulvert, CMP, 30" D‐37 78.00$ LFCulvert, CMP, 36" D‐38 130.00$ LFCulvert, CMP, 48" D‐39 190.00$ LFCulvert, CMP, 60" D‐40 270.00$ LFCulvert, CMP, 72" D‐41 350.00$ LFCulvert, Concrete, 8"D‐42 42.00$ LFCulvert, Concrete, 12"D‐43 48.00$ LFCulvert, Concrete, 15" D‐44 78.00$ LFCulvert, Concrete, 18"D‐45 48.00$ LFCulvert, Concrete, 24"D‐46 78.00$ LFCulvert, Concrete, 30"D‐47 125.00$ LFCulvert, Concrete, 36"D‐48 150.00$ LFCulvert, Concrete, 42"D‐49 175.00$ LFCulvert, Concrete, 48"D‐50 205.00$ LFCulvert, CPE, 6" (Not allowed in ROW)D‐51 14.00$ LFCulvert, CPE, 8" (Not allowed in ROW)D‐52 16.00$ LFCulvert, CPE, 12" (Not allowed in ROW)D‐53 24.00$ LFCulvert, CPE, 15" (Not allowed in ROW)D‐54 35.00$ LFCulvert, CPE, 18" (Not allowed in ROW)D‐55 41.00$ LFCulvert, CPE, 24" (Not allowed in ROW)D‐56 56.00$ LFCulvert, CPE, 30" (Not allowed in ROW)D‐57 78.00$ LFCulvert, CPE, 36" (Not allowed in ROW)D‐58 130.00$ LFCulvert, LCPE, 6" D‐59 60.00$ LFCulvert, LCPE, 8" D‐60 72.00$ LFCulvert, LCPE, 12" D‐61 84.00$ LFCulvert, LCPE, 15" D‐62 96.00$ LFCulvert, LCPE, 18" D‐63 108.00$ LFCulvert, LCPE, 24" D‐64 120.00$ LFCulvert, LCPE, 30" D‐65 132.00$ LFCulvert, LCPE, 36" D‐66 144.00$ LFCulvert, LCPE, 48" D‐67 156.00$ LFCulvert, LCPE, 54" D‐68168.00$ LFSUBTOTAL THIS PAGE:(B)(C)(D)(E)Page 8 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.c DRAINAGEUnit Prices Updated: 06/14/2016Version: 06/14/2016Printed 5/9/2017 CED Permit #:U‐16006774ExistingFuture PublicPrivateRight‐of‐WayImprovementsImprovements(D)(E)DescriptionNo. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Quant. CostSITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR DRAINAGE AND STORMWATER FACILITIESQuantity Remaining (Bond Reduction) (B)(C)DRAINAGE (Continued)Culvert, LCPE, 60" D‐69 180.00$ LFCulvert, LCPE, 72" D‐70 192.00$ LFCulvert, HDPE, 6" D‐71 42.00$ LFCulvert, HDPE, 8" D‐72 42.00$ LFCulvert, HDPE, 12" D‐73 74.00$ LF 33524,790.00Culvert, HDPE, 15" D‐74 106.00$ LF 909,540.00Culvert, HDPE, 18" D‐75 138.00$ LFCulvert, HDPE, 24" D‐76 221.00$ LFCulvert, HDPE, 30" D‐77 276.00$ LFCulvert, HDPE, 36" D‐78 331.00$ LFCulvert, HDPE, 48"D‐79 386.00$ LFCulvert, HDPE, 54"D‐80 441.00$ LFCulvert, HDPE, 60"D‐81 496.00$ LFCulvert, HDPE, 72"D‐82 551.00$ LFPipe, Polypropylene, 6"D‐83 84.00$ LFPipe, Polypropylene, 8"D‐84 89.00$ LFPipe, Polypropylene, 12"D‐85 95.00$ LFPipe, Polypropylene, 15"D‐86 100.00$ LFPipe, Polypropylene, 18"D‐87 106.00$ LFPipe, Polypropylene, 24"D‐88 111.00$ LFPipe, Polypropylene, 30" D‐89 119.00$ LFPipe, Polypropylene, 36" D‐90 154.00$ LFPipe, Polypropylene, 48" D‐91 226.00$ LFPipe, Polypropylene, 54" D‐92 332.00$ LFPipe, Polypropylene, 60" D‐93 439.00$ LFPipe, Polypropylene, 72" D‐94 545.00$ LFCulvert, DI, 6" D‐95 61.00$ LFCulvert, DI, 8" D‐96 84.00$ LFCulvert, DI, 12" D‐97 106.00$ LF 859,010.00Culvert, DI, 15" D‐98 129.00$ LFCulvert, DI, 18"D‐99 152.00$ LFCulvert, DI, 24"D‐100 175.00$ LFCulvert, DI, 30"D‐101 198.00$ LFCulvert, DI, 36"D‐102 220.00$ LFCulvert, DI, 48"D‐103 243.00$ LFCulvert, DI, 54"D‐104 266.00$ LFCulvert, DI, 60"D‐105 289.00$ LFCulvert, DI, 72"D‐106 311.00$ LFSUBTOTAL THIS PAGE:9,540.0033,800.00(B)(C)(D)(E)Page 9 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.c DRAINAGEUnit Prices Updated: 06/14/2016Version: 06/14/2016Printed 5/9/2017 CED Permit #:U‐16006774ExistingFuture PublicPrivateRight‐of‐WayImprovementsImprovements(D)(E)DescriptionNo. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Quant. CostSITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR DRAINAGE AND STORMWATER FACILITIESQuantity Remaining (Bond Reduction) (B)(C)Specialty Drainage ItemsDitching SD‐19.50$ CYFlow Dispersal Trench (1,436 base+)SD‐3 28.00$ LF French Drain (3' depth)SD‐4 26.00$ LFGeotextile, laid in trench, polypropylene SD‐53.00$ SYMid‐tank Access Riser, 48" dia, 6' deep SD‐6 2,000.00$ EachPond Overflow SpillwaySD‐7 16.00$ SYRestrictor/Oil Separator, 12"SD‐8 1,150.00$ EachRestrictor/Oil Separator, 15"SD‐9 1,350.00$ EachRestrictor/Oil Separator, 18"SD‐10 1,700.00$ EachRiprap, placedSD‐11 42.00$ CY142.00Tank End Reducer (36" diameter)SD‐12 1,200.00$ EachInfiltration pond testingSD‐13 125.00$ HRPermeable PavementSD‐14Permeable Concrete SidewalkSD‐15Culvert, Box __ ft x __ ftSD‐16SUBTOTAL SPECIALTY DRAINAGE ITEMS:42.00(B)(C)(D)(E)STORMWATER FACILITIES (Include Flow Control and Water Quality Facility Summary Sheet and Sketch)Detention Pond SF‐1Each Detention Tank SF‐2Each Detention Vault SF‐3Each Infiltration Pond SF‐4Each Infiltration Tank SF‐5Each Infiltration Vault SF‐6Each Infiltration Trenches SF‐7 300.00$ Each Basic Biofiltration Swale SF‐8Each Wet Biofiltration Swale SF‐9Each Wetpond SF‐10 Each Wetvault SF‐11 Each Sand Filter SF‐12 Each Sand Filter Vault SF‐13 Each Linear Sand Filter SF‐14 Each StormFilter SF‐15 29,500.00$ Each 129,500.00Rain GardenSF‐16Each SUBTOTAL STORMWATER FACILITIES:29,500.00(B)(C)(D)(E)Page 10 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.c DRAINAGEUnit Prices Updated: 06/14/2016Version: 06/14/2016Printed 5/9/2017 CED Permit #:U‐16006774ExistingFuture PublicPrivateRight‐of‐WayImprovementsImprovements(D)(E)DescriptionNo. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Quant. CostSITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR DRAINAGE AND STORMWATER FACILITIESQuantity Remaining (Bond Reduction) (B)(C)WRITE‐IN‐ITEMSWI‐1WI‐2WI‐3WI‐4WI‐5WI‐6WI‐7WI‐8WI‐9WI‐10WI‐11WI‐12WI‐13WI‐14WI‐15SUBTOTAL WRITE‐IN ITEMS:DRAINAGE AND STORMWATER FACILITIES SUBTOTAL: 17,800.00 35,542.00 7,007.00SALES TAX @ 9.5% 1,691.00 3,376.49 665.67DRAINAGE AND STORMWATER FACILITIES TOTAL: 19,491.00 38,918.49 7,672.67(B)(C)(D)(E)Page 11 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.c DRAINAGEUnit Prices Updated: 06/14/2016Version: 06/14/2016Printed 5/9/2017 CED Permit #:U‐16006774ExistingFuture PublicPrivateRight‐of‐WayImprovementsImprovements(D)(E)DescriptionNo. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Quant. CostConnection to Existing WatermainW‐1 2,000.00$ Each24,000.00Ductile Iron Watermain, CL 52, 4 Inch Diameter W‐2 50.00$ LFDuctile Iron Watermain, CL 52, 6 Inch Diameter W‐3 56.00$ LFDuctile Iron Watermain, CL 52, 8 Inch Diameter W‐4 60.00$ LF75945,540.00Ductile Iron Watermain, CL 52, 10 Inch Diameter W‐5 70.00$ LFDuctile Iron Watermain, CL 52, 12 Inch Diameter W‐6 80.00$ LFGate Valve, 4 inch DiameterW‐7 500.00$ EachGate Valve, 6 inch DiameterW‐8 700.00$ EachGate Valve, 8 Inch DiameterW‐9 800.00$ Each129,600.00Gate Valve, 10 Inch DiameterW‐10 1,000.00$ EachGate Valve, 12 Inch DiameterW‐11 1,200.00$ EachFire Hydrant AssemblyW‐12 4,000.00$ Each28,000.00Permanent Blow‐Off AssemblyW‐13 1,800.00$ Each23,600.00Air‐Vac Assembly, 2‐Inch DiameterW‐14 2,000.00$ EachAir‐Vac Assembly, 1‐Inch DiameterW‐15 1,500.00$ EachCompound Meter Assembly 3‐inch Diameter W‐16 8,000.00$ EachCompound Meter Assembly 4‐inch Diameter W‐17 9,000.00$ EachCompound Meter Assembly 6‐inch Diameter W‐18 10,000.00$ EachPressure Reducing Valve Station 8‐inch to 10‐inch W‐19 20,000.00$ EachWATER SUBTOTAL:70,740.00SALES TAX @ 9.5%6,720.30WATER TOTAL:77,460.30(B)(C)(D)(E)SITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR WATERQuantity Remaining (Bond Reduction) (B)(C)Page 12 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.d WATERUnit Prices Updated: 06/14/2016Version: 06/14/2016Printed 5/9/2017 CED Permit #:U‐16006774ExistingFuture PublicPrivateRight‐of‐WayImprovementsImprovements(D)(E)DescriptionNo. Unit Price Unit Quant. Cost Quant. Cost Quant. Cost Quant. CostClean OutsSS‐1 1,000.00$ EachGrease Interceptor, 500 gallonSS‐2 8,000.00$ EachGrease Interceptor, 1000 gallonSS‐3 10,000.00$ EachGrease Interceptor, 1500 gallonSS‐4 15,000.00$ EachSide Sewer Pipe, PVC. 4 Inch DiameterSS‐5 80.00$ LFSide Sewer Pipe, PVC. 6 Inch DiameterSS‐6 95.00$ LF30028,500.00Sewer Pipe, PVC, 8 inch DiameterSS‐7 105.00$ LF 47549,875.00Sewer Pipe, PVC, 12 Inch DiameterSS‐8 120.00$ LFSewer Pipe, DI, 8 inch DiameterSS‐9 115.00$ LFSewer Pipe, DI, 12 Inch DiameterSS‐10 130.00$ LFManhole, 48 Inch DiameterSS‐11 6,000.00$ Each 424,000.00Manhole, 54 Inch DiameterSS‐13 6,500.00$ EachManhole, 60 Inch DiameterSS‐15 7,500.00$ EachManhole, 72 Inch DiameterSS‐17 8,500.00$ EachManhole, 96 Inch DiameterSS‐19 14,000.00$ EachPipe, C‐900, 12 Inch DiameterSS‐21 180.00$ LFOutside DropSS‐24 1,500.00$ LSInside DropSS‐25 1,000.00$ LSSewer Pipe, PVC, ____ Inch DiameterSS‐26Lift Station (Entire System)SS‐27LSSANITARY SEWER SUBTOTAL:73,875.0028,500.00SALES TAX @ 9.5%7,018.132,707.50SANITARY SEWER TOTAL:80,893.1331,207.50(B)(C)(D)(E)SITE IMPROVEMENT BOND QUANTITY WORKSHEETFOR SANITARY SEWERQuantity Remaining (Bond Reduction) (B)(C)Page 13 of 14Ref 8‐H Bond Quantity WorksheetSECTION II.e SANITARY SEWERUnit Prices Updated: 06/14/2016Version: 06/14/2016Printed 5/9/2017 Planning Division |1055 South Grady Way – 6th Floor | Renton, WA 98057 (425) 430‐7200Date:Name:Project Name: PE Registration No:CED Plan # (LUA):Firm Name:CED Permit # (U):Firm Address:Site Address:Phone No.Parcel #(s):Email Address:Project Phase: Site Restoration/Erosion Sediment Control Subtotal(a)(a)9,246.51$ Existing Right‐of‐Way Improvements Subtotal (b) (b)81,369.45$ Future Public Improvements Subtotal (c) (c)147,918.08$ Stormwater & Drainage Facilities Subtotal (d) (d)66,082.16$ Bond Reduction (Quantity Remaining)2(e)(e)‐$ Site RestorationCivil Construction PermitMaintenance Bond59,073.94$ Bond Reduction2Construction Permit Bond Amount 3Minimum Bond Amount is $10,000.001 Estimate Only ‐ May involve multiple and variable components, which will be established on an individual basis by Development Engineering.2 The City of Renton allows one request only for bond reduction prior to the maintenance period. Reduction of not more than 70% of the original bond amount, provided that the remaining 30% willcover all remaining items to be constructed. 3 Required Bond Amounts are subject to review and modification by Development Engineering.* Note: The word BOND as used in this document means any financial guarantee acceptable to the City of Renton.** Note: All prices include labor, equipment, materials, overhead and profit. T(P +R ‐ S)Prepared by:Project InformationCONSTRUCTION BOND AMOUNT */**(prior to permit issuance)425‐250‐7223Tho@thebluelinegroup.comLangston Properties 303‐315 SW Langston Road8663500‐040, ‐045, ‐050, ‐060, ‐065FOR APPROVALU‐1600677425 Central Way, Suite 400, Kirkland, WA 98003456,924.28$ P (a) x 150%SITE IMPROVEMENT BOND QUANTITY WORKSHEET BOND CALCULATIONS5/9/2017Timothy M. Ho, PE54277The Blueline GroupR((b)+(c)+(d)) x 150%EST1((b) + (c) + (d)) x 20%‐$ MAINTENANCE BOND */**(after final acceptance of construction)9,246.51$ 81,369.45$ 443,054.52$ 13,869.76$ ‐$ 147,918.08$ 66,082.16$ S(e) x 150%Page 14 of 14Ref 8‐H Bond Quantity WorksheetSECTION III. BOND WORKSHEETUnit Prices Updated: 06/14/2016Version: 06/14/2016Printed 5/9/2017 Langston Properties Technical Information Report 16-029 10-1 SECTION 10 OPERATIONS AND MAINTENANCE An Operations and Maintenance Manual is provided on the following pages. APPENDIX A MAINTENANCE REQUIREMENTS FOR FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES 2009 Surface Water Design Manual – Appendix A 1/9/2009 A-9 NO. 5 – CATCH BASINS AND MANHOLES Maintenance Component Defect or Problem Condition When Maintenance is Needed Results Expected When Maintenance is Performed Sediment Sediment exceeds 60% of the depth from the bottom of the catch basin to the invert of the lowest pipe into or out of the catch basin or is within 6 inches of the invert of the lowest pipe into or out of the catch basin. Sump of catch basin contains no sediment. Trash or debris of more than ½ cubic foot which is located immediately in front of the catch basin opening or is blocking capacity of the catch basin by more than 10%. No Trash or debris blocking or potentially blocking entrance to catch basin. Trash or debris in the catch basin that exceeds1/3 the depth from the bottom of basin to invert the lowest pipe into or out of the basin. No trash or debris in the catch basin. Dead animals or vegetation that could generate odors that could cause complaints or dangerous gases (e.g., methane). No dead animals or vegetation present within catch basin. Trash and debris Deposits of garbage exceeding 1 cubic foot in volume. No condition present which would attract or support the breeding of insects or rodents. Corner of frame extends more than ¾ inch past curb face into the street (If applicable). Frame is even with curb. Top slab has holes larger than 2 square inches or cracks wider than ¼ inch. Top slab is free of holes and cracks. Damage to frame and/or top slab Frame not sitting flush on top slab, i.e., separation of more than ¾ inch of the frame from the top slab. Frame is sitting flush on top slab. Cracks wider than ½ inch and longer than 3 feet, any evidence of soil particles entering catch basin through cracks, or maintenance person judges that catch basin is unsound. Catch basin is sealed and structurally sound. Cracks in walls or bottom Cracks wider than ½ inch and longer than 1 foot at the joint of any inlet/outlet pipe or any evidence of soil particles entering catch basin through cracks. No cracks more than 1/4 inch wide at the joint of inlet/outlet pipe. Settlement/ misalignment Catch basin has settled more than 1 inch or has rotated more than 2 inches out of alignment. Basin replaced or repaired to design standards. Damaged pipe joints Cracks wider than ½-inch at the joint of the inlet/outlet pipes or any evidence of soil entering the catch basin at the joint of the inlet/outlet pipes. No cracks more than ¼-inch wide at the joint of inlet/outlet pipes. Structure Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries or paint. Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Sediment accumulation Sediment filling 20% or more of the pipe. Inlet/outlet pipes clear of sediment. Trash and debris Trash and debris accumulated in inlet/outlet pipes (includes floatables and non-floatables). No trash or debris in pipes. Inlet/Outlet Pipe Damaged Cracks wider than ½-inch at the joint of the inlet/outlet pipes or any evidence of soil entering at the joints of the inlet/outlet pipes. No cracks more than ¼-inch wide at the joint of the inlet/outlet pipe. APPENDIX A MAINTENANCE REQUIREMENTS FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES 1/9/2009 2009 Surface Water Design Manual – Appendix A A-10 NO. 5 – CATCH BASINS AND MANHOLES Maintenance Component Defect or Problem Condition When Maintenance is Needed Results Expected When Maintenance is Performed Unsafe grate opening Grate with opening wider than 7/8 inch. Grate opening meets design standards. Trash and debris Trash and debris that is blocking more than 20% of grate surface. Grate free of trash and debris. footnote to guidelines for disposal Metal Grates (Catch Basins) Damaged or missing Grate missing or broken member(s) of the grate. Any open structure requires urgent maintenance. Grate is in place and meets design standards. Cover/lid not in place Cover/lid is missing or only partially in place. Any open structure requires urgent maintenance. Cover/lid protects opening to structure. Locking mechanism Not Working Mechanism cannot be opened by one maintenance person with proper tools. Bolts cannot be seated. Self-locking cover/lid does not work. Mechanism opens with proper tools. Manhole Cover/Lid Cover/lid difficult to Remove One maintenance person cannot remove cover/lid after applying 80 lbs. of lift. Cover/lid can be removed and reinstalled by one maintenance person. APPENDIX A MAINTENANCE REQUIREMENTS FOR FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES 2009 Surface Water Design Manual – Appendix A 1/9/2009 A-11 NO. 6 – CONVEYANCE PIPES AND DITCHES Maintenance Component Defect or Problem Conditions When Maintenance is Needed Results Expected When Maintenance is Performed Sediment & debris accumulation Accumulated sediment or debris that exceeds 20% of the diameter of the pipe. Water flows freely through pipes. Vegetation/roots Vegetation/roots that reduce free movement of water through pipes. Water flows freely through pipes. Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries or paint. Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Damage to protective coating or corrosion Protective coating is damaged; rust or corrosion is weakening the structural integrity of any part of pipe. Pipe repaired or replaced. Pipes Damaged Any dent that decreases the cross section area of pipe by more than 20% or is determined to have weakened structural integrity of the pipe. Pipe repaired or replaced. Trash and debris Trash and debris exceeds 1 cubic foot per 1,000 square feet of ditch and slopes. Trash and debris cleared from ditches. Sediment accumulation Accumulated sediment that exceeds 20% of the design depth. Ditch cleaned/flushed of all sediment and debris so that it matches design. Noxious weeds Any noxious or nuisance vegetation which may constitute a hazard to County personnel or the public. Noxious and nuisance vegetation removed according to applicable regulations. No danger of noxious vegetation where County personnel or the public might normally be. Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries or paint. Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Vegetation Vegetation that reduces free movement of water through ditches. Water flows freely through ditches. Erosion damage to slopes Any erosion observed on a ditch slope. Slopes are not eroding. Ditches Rock lining out of place or missing (If Applicable) One layer or less of rock exists above native soil area 5 square feet or more, any exposed native soil. Replace rocks to design standards. APPENDIX A MAINTENANCE REQUIREMENTS FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES 1/9/2009 2009 Surface Water Design Manual – Appendix A A-16 NO. 11 – GROUNDS (LANDSCAPING) Maintenance Component Defect or Problem Conditions When Maintenance is Needed Results Expected When Maintenance is Performed Trash or litter Any trash and debris which exceed 1 cubic foot per 1,000 square feet (this is about equal to the amount of trash it would take to fill up one standard size office garbage can). In general, there should be no visual evidence of dumping. Trash and debris cleared from site. Noxious weeds Any noxious or nuisance vegetation which may constitute a hazard to County personnel or the public. Noxious and nuisance vegetation removed according to applicable regulations. No danger of noxious vegetation where County personnel or the public might normally be. Contaminants and pollution Any evidence of contaminants or pollution such as oil, gasoline, concrete slurries or paint. Materials removed and disposed of according to applicable regulations. Source control BMPs implemented if appropriate. No contaminants present other than a surface oil film. Site Grass/groundcover Grass or groundcover exceeds 18 inches in height. Grass or groundcover mowed to a height no greater than 6 inches. Hazard Any tree or limb of a tree identified as having a potential to fall and cause property damage or threaten human life.A hazard tree identified by a qualified arborist must be removed as soon as possible. No hazard trees in facility. Limbs or parts of trees or shrubs that are split or broken which affect more than 25% of the total foliage of the tree or shrub. Trees and shrubs with less than 5% of total foliage with split or broken limbs. Trees or shrubs that have been blown down or knocked over. No blown down vegetation or knocked over vegetation. Trees or shrubs free of injury. Trees and Shrubs Damaged Trees or shrubs which are not adequately supported or are leaning over, causing exposure of the roots. Tree or shrub in place and adequately supported; dead or diseased trees removed. APPENDIX A MAINTENANCE REQUIREMENTS FOR FLOW CONTROL, CONVEYANCE, AND WQ FACILITIES 2009 Surface Water Design Manual – Appendix A 1/9/2009 A-35 NO. 24 – CATCH BASIN INSERT Maintenance Component Defect or Problem Conditions When Maintenance is Needed Results Expected When Maintenance is Performed Visible Oil Visible oil sheen passing through media Media inset replaced. Insert does not fit catch basin properly Flow gets into catch basin without going through media. All flow goes through media. Filter media plugged Filter media plugged.Flow through filter media is normal. Oil absorbent media saturated Media oil saturated. Oil absorbent media replaced. Water saturated Catch basin insert is saturated with water, which no longer has the capacity to absorb. Insert replaced. Service life exceeded Regular interval replacement due to typical average life of media insert product, typically one month. Media replaced at manufacturer’s recommended interval. Media Insert Seasonal maintenance When storms occur and during the wet season. Remove, clean and replace or install new insert after major storms, monthly during the wet season or at manufacturer’s recommended interval.