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HomeMy WebLinkAboutRS_TIR_3-15-19 Civil Engineers ● Structural Engineers ● Landscape Architects ● Community Planners ● Land Surveyors Technical Information Report PREPARED FOR: Ronhovde Architects LLC 14900 Interurban Ave S, Suite 138 Tukwila, WA 98168 PROJECT: Compton Lumber Renton 2940, 2960, 2980, and 2990 East Valley Road Renton, WA 98057 2190112.10 PREPARED BY: Daniel Hendrickson, EIT Project Engineer REVIEWED BY: Todd C. Sawin, PE, DBIA, LEED AP Principal DATE: March 2019 Technical Information Report PREPARED FOR: Ronhovde Architects LLC 14900 Interurban Ave S, Suite 138 Tukwila, WA 98168 PROJECT: Compton Lumber Renton 2940, 2960, 2980, and 2990 East Valley Road Renton, WA 98057 2190112.10 PREPARED BY: Daniel Hendrickson, EIT Project Engineer REVIEWED BY: Todd C. Sawin, PE, DBIA, LEED AP Principal DATE: March 2019 I hereby state that this Technical Information Report for the Compton Lumber Renton project has been prepared by me or under my supervision, and meets the standard of care and expertise that is usual and customary in this community for professional engineers. I understand that City of Renton does not and will not assume liability for the sufficiency, suitability, or performance of drainage facilities prepared by me. Technical Information Report 2940, 2960, 2980, and 2990 East Valley Road Renton, WA 98057 2190112.10 Table of Contents 1.0 Project Overview ............................................................................................................................ 1 Purpose and Scope............................................................................................................. 1 1.1 Existing Conditions.............................................................................................................. 1 1.2 Post-Development Conditions ............................................................................................ 1 1.3 2.0 Conditions and Requirements Summary .................................................................................... 2 Core Requirements ............................................................................................................. 2 2.1 2.1.1 CR 1 – Discharge at the Natural Location ............................................................. 2 2.1.2 CR 2 – Offsite Analysis .......................................................................................... 2 2.1.3 CR 3 – Flow Control ............................................................................................... 2 2.1.4 CR 4 – Conveyance System .................................................................................. 2 2.1.5 CR 5 – Construction Stormwater Pollution Prevention .......................................... 3 2.1.6 CR 6 – Maintenance and Operations .................................................................... 3 2.1.7 CR 7 – Financial Guarantees and Liability ............................................................ 3 2.1.8 CR 8 – Water Quality Facilities .............................................................................. 3 2.1.9 CR 9 – Onsite BMPs .............................................................................................. 3 2.1.10 SR 1 – Other Adopted Area-Specific Requirements.............................................. 3 2.1.11 SR 2 – Flood Hazard Area Delineation .................................................................. 3 2.1.12 SR 3 – Flood Protection Facilities .......................................................................... 3 2.1.13 SR 4 – Source Controls ......................................................................................... 3 2.1.14 SR 5 – Oil Control .................................................................................................. 4 2.1.15 SR 6 – Aquifer Protection Area .............................................................................. 4 3.0 Offsite Analysis .............................................................................................................................. 4 Task 1 – Study Area Definition and Maps........................................................................... 4 3.1 Task 2 – Resource Review ................................................................................................. 4 3.2 Task 3 – Field Inspection .................................................................................................... 4 3.3 Task 4 – Drainage System Description and Problem Descriptions .................................... 6 3.4 4.0 Flow Control and Water Quality Facility Analysis and Design.................................................. 6 Flow Control ........................................................................................................................ 6 4.1 4.1.1 Existing Site Hydrology (Part A) ............................................................................. 6 4.1.2 Developed Site Hydrology (Part B) ........................................................................ 6 4.1.3 Performance Standards (Part C) ........................................................................... 7 4.1.4 Flow Control System (Part D) ................................................................................ 7 Water Quality System (Part E) ............................................................................................ 8 4.2 Technical Information Report 2940, 2960, 2980, and 2990 East Valley Road Renton, WA 98057 2190112.10 5.0 Conveyance System Analysis and Design .................................................................................. 8 6.0 Special Reports and Studies ........................................................................................................ 8 7.0 Other Permits ................................................................................................................................. 9 8.0 CSWPPP Analysis and Design ..................................................................................................... 9 9.0 Bond Quantities, Facility Summaries, and Declaration of Covenant ....................................... 9 10.0 Operations and Maintenance Plan ............................................................................................... 9 11.0 Conclusion ...................................................................................................................................... 9 Technical Information Report 2940, 2960, 2980, and 2990 East Valley Road Renton, WA 98057 2190112.10 Appendices Appendix A Exhibits A-1 .................... Vicinity Map A-2 .................... TIR Worksheet A-3 .................... Developed Conditions Map A-4 .................... Drainage Basin Map Appendix B Exhibits B-1 .................... Geotechnical Report by Terra Associates, Inc., January 24, 2017 B-2 .................... NRCS Soil Survey B-3 .................... Wetland and Fish and Wildlife Habitat Assessment and Restoration Plan by Soundview Consultants LLC, June 2017 B-4 .................... Downstream Analysis Map Appendix C Exhibits C-1.................... Flood Insurance Rate Map C-2.................... Groundwater Protection Areas Map C-3.................... Department of Ecology CULD - Filterra Appendix D Exhibits D-1.................... Flow Control Application Map D-2.................... WWHM Flow Control Calculations D-3.................... 25-Year Conveyance Simulation D-4.................... Filterra Sizing Calculations Appendix E Exhibits E-1 .................... Operations & Maintenance Guide Technical Information Report 2940, 2960, 2980, and 2990 East Valley Road Renton, WA 98057 1 2190112.10 1.0 Project Overview Purpose and Scope 1.1 This report accompanies the civil engineering plans and documents for the Compton Lumber Renton project located at 2940, 2960, 2980, and 2990 East Valley Road in Renton , Washington. The site is divided into four parcels: 3023059091 (southwest), 3023059096 (north), 3023059098 (central), and 3023059099 (south). The project proposes to consolidate three of the four parcels into a single parcel, and then develop the site with a 50,000-square foot retail/commercial building, associated parking, and a paved lumberyard. The project site is approximately 4.28 acres in size. See Figure 1-1 for the TIR Worksheet and Figure 1-2 for a Site Location map. The site is located within the city of Renton, which has amended the 2016 King County Surface Water Design Manual (KCSWDM) as the 2016 City of Renton Surface Water Design Manual (CRSWDM). Per the CRSWDM, the Peak Rate Flow Control Standard shall be met along with the Basic Enhanced Water Quality Treatment Menu. Existing Conditions 1.2 The existing site is mostly impervious and developed with several separate businesses: Lumber Market located at 2940 East Valley Road, Parcel No. 3023059096; Skyway Towing located at 2960 East Valley Road, Parcel Nos. 3023059098 and 3023059099; and Milt’s Trucking & Excavation located at 2990 East Valley Road, Parcel No. 3023059091. There is an existing Category III wetland located on the eastern border of the site. Pervious surfaces consist of areas located in the existing wetland buffer. The topography across the site is very flat, with most of the project site ranging in elevation from 18 to 20 feet, with a slight slope running north to south. The site drops at the south and east borders down to the existing wetland. Slopes across the site are typically between 1 and 5 percent. According to the City of Renton Public Works Department Soil Survey, Reference 15-C of the CRSWDM, the site consists of Tukwila muck (approximately 67 percent) and urban land (approximately 33 percent). These soils were confirmed by the USDA National Resource Conservation Service Soil Survey. The existing site is split into several different subbasins, all of which are tributary to the publically owned drainage system in East Valley Road. Most of the site sheet flows to existing drainage structures or directly to the existing wetland along the east side of the site. This existing wetland overflows into a drainage ditch south of the site; this ditch conveys water west to the public ly owned drainage system in East Valley Road. The southwest parcel (3023059091) discharges south to this drainage ditch. The parking lot west of Skyway Towing and the existing Skyway Towing building discharge west directly into the East Valley Road conveyance system. The existing drainage patterns have been analyzed and are discussed in detail in the Level One Downstream Analysis (see Section 3.0). Post-Development Conditions 1.3 The project proposes to construct a new 50,000-square foot building on the north side of the site with retail sales space, office space, and a lumber sales warehouse. The site also includes a parking lot and lumberyard, which will be paved with asphalt. Stormwater runoff generated on impervious pollution generating surfaces will sheet flow to proposed inlets before being conveyed via subsurface pipes to a Contech Filter Vault for water quality treatment. This runoff will discharge west toward the publically owned drainage system in East Valley Road, matching the natural drainage path of the site. Runoff generated on the Technical Information Report 2940, 2960, 2980, and 2990 East Valley Road Renton, WA 98057 2 2190112.10 proposed 50,000-square foot building and any other rood systems will be piped to the edge of the wetland buffer where the water will discharge into an engineered level spreader. From there, stormwater will flow through the 56.25-foot wetland buffer and discharge into the wetland to the east and south sides of the site. This wetland drains into East Valley Road to the west; therefore, maintaining the natural drainage pattern. Under the proposed conditions, we are proposing approximately 50,000 square feet of impervious roof area to discharge into the wetland; we feel this is close to matching the current conditions of the site. See Appendix A for a Drainage Basin and Developed Conditions Map. 2.0 Conditions and Requirements Summary Core Requirements 2.1 2.1.1 CR 1 – Discharge at the Natural Location Stormwater runoff generated on the existing project site discharges both east to the existing wetland and west to the publically owned drainage system in East Valley Road. The existing wetland overflows into the existing drainage ditch south of the project site, which discharges to the drainage system in East Valley Road. The proposed project site follows this existing drainage path by discharging all treated runoff west to the drainage system in East Valley Road, and discharging all clean runoff from the roofs east to the wetland. This matches the existing conditions, meeting the requirement for discharging at the natural location. 2.1.2 CR 2 – Offsite Analysis AHBL staff performed a Level One Downstream Analysis for the project. The analysis included:  Defining and mapping the study area.  Reviewing available information on the study area.  Field inspecting the study area. Please refer to Section 3.0 for the full offsite analysis. 2.1.3 CR 3 – Flow Control The project is located in a Peak Flow Rate Control Standard area. This flow control standard requires the peak flow rate under developed conditions to be equal to or less than the peak flow rate under existing conditions, as stated in the 2017 CRSWDM. Flow control is discussed in further detail in Section 4.0, Flow Control and Water Quality Facility Analysis and Design. 2.1.4 CR 4 – Conveyance System The proposed conveyance system has been designed to meet the requirements outlined in Section 1.2.4 of the CRSWDM. Refer to Section 5.0 for more information. Technical Information Report 2940, 2960, 2980, and 2990 East Valley Road Renton, WA 98057 3 2190112.10 2.1.5 CR 5 – Construction Stormwater Pollution Prevention Onsite land disturbance will consist of clearing the site, demolition of several existing onsite buildings, and regrading of the site. A Construction Stormwater Pollution Prevention Plan (CSWPPP) has been prepared and is included under a separate cover. 2.1.6 CR 6 – Maintenance and Operations Maintenance and operations of all drainage facilities is the responsibility of the owner. A completed Operations and Maintenance Plan has been prepared and is included in Appendix E. 2.1.7 CR 7 – Financial Guarantees and Liability All financial guarantee and liability requirements will be met by the owner and will be provided with the final engineering design. This project will provide a Drainage Facilities Restoration and Site Stabilization Financial Guarantee. 2.1.8 CR 8 – Water Quality Facilities The project site is subject to the Enhanced Basic Water Quality Treatment Menu per the CRSWDM. Design of these water quality facilities is discussed in Section 4.0. 2.1.9 CR 9 – Onsite BMPs The Compton Lumber Renton project is classified as a Large Lot per Section 1.2.9.2 of the CRSWDM. The proposed project site meets the Large Lot Best Management Practice (BMP) Requirements outlined in Section 1.2.9.2.2 of the CRSWDM. The basic dispersion BMP will be utilized for all roof areas meeting the above requirements. 2.1.10 SR 1 – Other Adopted Area-Specific Requirements To our knowledge, there are no adopted area-specific requirements that are applicable to the project site. 2.1.11 SR 2 – Flood Hazard Area Delineation Flood Insurance Rate Map No. 53033C0979 F, Panel 979 of 1725, was consulted for this project and shows the project site within the Zone X area, which is described as areas determined to be outside of the 500-year floodplain. Refer to Appendix C-1 for the Flood Insurance Rate Map. 2.1.12 SR 3 – Flood Protection Facilities The project site does not contain, nor is it adjacent to, any existing flood protection facilities. Project improvements do not include flood protection measures. 2.1.13 SR 4 – Source Controls The proposed project is classified as a commercial site. Water quality source controls applicable to the project site shall be evaluated and applied, as described in the King County Stormwater Pollution Prevention Manual (KCSWPPM) and Renton Municipal Code IV. Technical Information Report 2940, 2960, 2980, and 2990 East Valley Road Renton, WA 98057 4 2190112.10 2.1.14 SR 5 – Oil Control The project is not considered a high-use site. Therefore, it is not subject to oil control requirements. 2.1.15 SR 6 – Aquifer Protection Area According to the City of Renton Public Works Department Groundwater Protection Areas map (Reference 15-B of the CRSWDM), the site is not located within an aquifer protection area. Refer to Appendix C-2 for the above referenced map. 3.0 Offsite Analysis Task 1 – Study Area Definition and Maps 3.1 Ronhovde Architects LLC proposes to construct a new commercial site along East Valley Road in Renton, Washington. AHBL staff visited the site on May 11, 2017, to perform a Level 1 Downstream Analysis. There are no upstream tributary areas contributing stormwater to the onsite basin area. The entire project site is tributary to the same threshold discharge area (TDA). This TDA is the existing publically owned, underground, piped conveyance system in East Valley Road. This conveyance system eventually discharges to Panther Creek , which is a tributary to Springbrook Creek, and then the Black River. The existing discharge point to Panther Creek is over a quarter mile from the project site. Task 2 – Resource Review 3.2 The following resources were reviewed to determine if there are any existing or potential problems in the study area:  Adopted Basin Plans: The project lies within the Black River Water Subbasin. Requirements for the Black River Water Subbasin will be followed where applicable.  Offsite Analysis Reports: AHBL staff has not located offsite analysis reports for projects near the Compton Lumber Renton project site.  FEMA Map: FEMA Flood Insurance Rate Map No. 53033C0979 F, Panel 979 of 1725, dated May 16, 1995, (see Appendix C-1) indicates that the project site lies outside the categorized flood zones.  Topographic survey. Task 3 – Field Inspection 3.3 On May 11, 2017, AHBL staff performed a Downstream Analysis of the drainage system receiving stormwater runoff from the proposed Compton Lumber Renton project site. 1. Investigate any problems reported or observed during the resource review: No problems were reported or observed during the resource review. Technical Information Report 2940, 2960, 2980, and 2990 East Valley Road Renton, WA 98057 5 2190112.10 2. Locate all existing/potential constrictions or lack of capacity in the existing drainage system: No constrictions or lack of capacity in the existing drainage system was observed. 3. Identify all existing/potential downstream drainage problems, as defined in Section 1.2.2.1: No existing/potential downstream drainage problems were observed. 4. Identify existing/potential overtopping, scouring, bank sloughing, or sedimentation: No existing/potential overtopping, scouring, bank sloughing, or sedimentation was observed. 5. Identify significant destruction of aquatic habitat or organisms (e.g., severe siltation, bank erosion, or incision in a stream): No significant destruction of aquatic habitat or organisms was observed. 6. Collect qualitative data on features such as land use, impervious surfaces, topography, and soil types for the site: Land use on the project site is commercial, similar to proposed. Impervious surfaces include asphalt, gravel, and buildings, which cover the majority of the project site outside of the existing wetland buffer. The topography is flat outside of the wetland buffer, and the soil type is Tukwila muck and urban land. 7. Collect information on pipe sizes, channel characteristics, drainage structures, and relevant critical areas (e.g., wetlands, stream, and steep slopes): Pipe sizes in the East Valley Road conveyance system are 30-inch and eventually increase to 36-inch prior to discharging to Panther Creek. There are no steep slopes located on the project site. There is a Category III wetland located on the eastern border of the property. The drainage ditch on the southern property border is non-regulated. Refer to Appendix B-3 for the Wetland Report. 8. Verify tributary basins delineated in Task 1: Based on the topography found onsite and offsite, the basin delineation based on the survey was confirmed. 9. Contract neighboring property owners or residents in the area about past or existing drainage problems, and describe these in the report (optional): This requirement is not applicable for this project. The project site does not discharge to an offsite conveyance system or to adjacent private properties. 10. Note the date and weather conditions at the time of inspection: The site visit occurred on May 11, 2017. The weather was overcast and 40 degrees. Technical Information Report 2940, 2960, 2980, and 2990 East Valley Road Renton, WA 98057 6 2190112.10 Task 4 – Drainage System Description and Problem Descriptions 3.4 The site is located within the Black River Subbasin. The site is divided into four separate drainage subbasins and one TDA. The proposed TDA is the publically owned and maintained East Valley Road conveyance system. This public, piped system eventually discharges to Panther Creek. The discharge to panther creek is over one-quarter mile from the project site. No signs of flooding, overtopping, or erosion were evident at the time of the inspection. A Downstream Analysis Map has been prepared and can be found in Appendix B-4. 4.0 Flow Control and Water Quality Facility Analysis and Design Flow Control 4.1 4.1.1 Existing Site Hydrology (Part A) The existing site is developed with existing buildings, asphalt, and gravel storage areas. The site is mostly impervious, except for the existing wetland area on the east side of the site. Runoff generated on the existing site sheet flows to existing onsite catch basins before discharging east to the existing wetland east of the site. The Western Washington Hydrology Model (WWHM) was used to model the existing site and determine peak flows. 4.1.2 Developed Site Hydrology (Part B) The project site will be split into two separate drainage basins. The first basin includes the proposed parking area and the partially covered outdoor lumber sales areas. This basin will collect stormwater runoff via a series of inlets and convey the water via subsurface pipes to one of two Filterra vaults, before discharging to the City of Renton stormwater system located within East Valley Road. The second basin includes the covered lumber sales areas and the retail/warehouse building. All stormwater will be collected and conveyed via a tight-lined roof drainage system to an engineered level spreader. Here the stormwater will travel through the 56-foot flow path before dispersing into the wetlands located to the east and south of the property, and will eventually be conveyed to the storm drainage system located in East Valley Road. The project site is located within a Peak Rate Flow Control Standard area (see Appendix D-1 for the Flow Control Application Map). This standard requires that developed peak flows match existing flows for the 2-, 10-, and 100-year return period stormwater events. Under proposed conditions, net impervious area is planned to decrease, thus lowering peak flow rates and meeting the Peak Rate Flow Control Standard. WWHM peak flow calculations have been prepared and can be found in Appendix D-2 The annual peak flows and durations for the proposed site were determined using the existing and developed surface areas shown below. Table 1 – Existing vs. Developed Site Hydrology Description Impervious Area (Acres) Pervious Area (Acres) Wetland Area (Acres) Total Areas (Acres) Existing 4.03 0.09 0.16 4.28 Technical Information Report 2940, 2960, 2980, and 2990 East Valley Road Renton, WA 98057 7 2190112.10 Developed 2.75 1.37 0.16 4.28 4.1.3 Performance Standards (Part C) Area-Specific Flow Control Facility Standard The project site is located within a Peak Rate Flow Control Standard area. This standard requires that the proposed project site match existing peak flow rates for the 2-, 10-, and 100-year stormwater events. Under the proposed conditions, peak flow rates will decrease for all of the above stormwater events, meeting the flow control exception of the 2017 CRSWDM. These calculations can be found in Appendix D-2. Conveyance System Capacity Standards The onsite stormwater network was sized to convey all runoff during a 25-year peak storm event. The pipe network conveyance was analyzed using Flow Master and the peak 25-year flow rate as determined by WWHM. See Appendix D-3 for the pipe flow conveyance calculations. Water Quality Treatment Menu In accordance with the 2016 CRSWDM, onsite flows will be treated to specifications provided by the Enhanced Basic Water Quality standards. The goal of this treatment menu is to reduce total suspended solids (TSS) by 80 percent and to reduce zinc concentration by 50 percent for a typical rainfall year. This goal will be accomplished by providing new Contech Filterra vault structures for target pollution generating impervious surfaces, satisfying Enhanced Basic Option 5 – Proprietary Facility, found in Section 6.1.2 of the CRSWDM. The proposed filter vault has been sized and will be maintained per the Department of Ecology (DOE) General Use Level Designation (GULD). The DOE’s GULD has been included in Appendix C-3. Source Controls The proposed project consists of new parking, retail and warehouse buildings, and outdoor storage areas. Source control and erosion and sediment control measures during construction are included in a CSWPPP, which is provided under a separate cover. Oil Controls Not applicable. 4.1.4 Flow Control System (Part D) The proposed project site will have a greater percentage of pervious surface coverage than the existing site. This increase in pervious surfacing will decrease peak flows and satisfy the Peak Rate Flow Control Standard. WWHM calculations are provided in Appendix D-2, showing that the proposed peak flow rates are less than the existing conditions. Below is a review of each LID BMP and whether it is suitable for the proposed development.  Full Dispersion – Full dispersion is infeasible for this site because a 100-foot flow path of native vegetative surface does not exist on the property. Therefore, full dispersion is not an option for the proposed project. Technical Information Report 2940, 2960, 2980, and 2990 East Valley Road Renton, WA 98057 8 2190112.10  Full Infiltration – The existing soil within the project area is high in silt content and has a high groundwater table (as evidenced by the wetland on the east side of the site). Infiltration of stormwater is not feasible on this site.  Limited Infiltration – The existing soil within the project area is high in silt content and has a high groundwater table (as evidenced by the wetland on the east side of the site). Infiltration of stormwater is not feasible on this site.  Basic Dispersion – Basic dispersion is an option for non-pollution generating hard surfaces on this site. The topography of the site and the hydrogeological makeup of the site will not allow for stormwater to be treated and dispersed under the basic dispersion criteria. However, non-pollution generating surfaces can utilize basic dispersion on the project.  Bioretention – Due to the limited site area available for the proposed building and parking area, there is no room available to provide bioretention within the project site. This reduction in usable space would make the site unusable for the proposed use. Along with the reduction in space, the high groundwater table and lack of sufficient infiltration across the site make bioretention infeasible for this project.  Permeable Pavement – Due to the high content of silt in the existing soils onsite, the geotechnical engineer recommends capping the existing soils and providing positive drainage away from the proposed building to stabilize the soils onsite. Introducing surface water into the soils beneath the parking area would decrease the structural integrity of the soils and is not recommended. Water Quality System (Part E) 4.2 The new pollution generating impervious surfaces for the proposed site will be treated using three new Filterra vaults to provide Enhanced Basic Treatment. Ninety-one percent of influent runoff will be treated via these vaults before discharging in the municipal storm system. The system was modeled in WWHM as a sand filter, as instructed by DOE’s CULD. Screenshots showing the designed system meeting the 91 percent treatment requirement can be found in Appendix D-4. 5.0 Conveyance System Analysis and Design The conveyance for the storm drainage system was analyzed using Flow Master and WWHM. Using WWHM it was determined that the 25-year peak flow rate for the developed site is 2.02 cubic feet per second. Using this flow rate the normal depth of a 1 foot diameter pipe running at 0.5 percent slope was determined. The normal depth of this pipe is .57 feet. Therefore, the conveyance system has adequate capacity to serve this site. For calculations, see Appendix D-3. 6.0 Special Reports and Studies A Geotechnical Report by Terra Associates, Inc., dated January 24, 2017, is included in Appendix B-1. A Wetland and Fish and Wildlife Habitat Assessment and Restoration Plan by Soundview Consultants LLC, dated June 2017, is included in Appendix B-3. Technical Information Report 2940, 2960, 2980, and 2990 East Valley Road Renton, WA 98057 9 2190112.10 7.0 Other Permits Required permits for the project may include a Construction Stormwater NPDES Permit for the proposed construction, a City of Renton commercial building permit, and a City of Renton Construction Activity Permit. 8.0 CSWPPP Analysis and Design A CSWPPP has been prepared and is included in this submittal package under a separate cover. 9.0 Bond Quantities, Facility Summaries, and Declaration of Covenant A bond quantity worksheet has been prepared and is included in this submittal package. 10.0 Operations and Maintenance Plan The drainage facilities detailed in this report will be privately owned and maintained. Maintenance instructions have been prepared for all onsite drainage facilities; these can be found in Appendix E. 11.0 Conclusion This site has been designed to meet the 2016 King County Surface Water Design Manual (KCSWDM), as amended by the City of Renton, the 2016 City of Renton Surface Water Design Manual (CRSWDM). The site utilizes water quality facilities to treat stormwater draining from the site. It was determined using these criteria that:  The site will meet the Peak Rate Flow Control Standard for Flow Control.  Water quality facilities have been designed to meet the required Enhanced Basic Water Quality Treatment Level for the site.  Pipe networks will be designed to be of adequate size to effectively convey the 25-year storm event and to contain the 100-year storm event. This analysis is based on data and records either supplied to or obtained by AHBL. These doc uments are referenced within the text of the analysis. The analysis has been prepared utilizing procedures and practices within the standard accepted practices of the industry. We conclude that this project, as schematically represented, will not create any new problems within the downstream drainage system. This project will not noticeably aggravate any existing downstream problems due to either water quality or quantity. AHBL, Inc. Technical Information Report 2940, 2960, 2980, and 2990 East Valley Road Renton, WA 98057 10 2190112.10 Daniel Hendrickson, EIT Project Engineer DJH/lsk March 2019 Q:\2019\2190112\10_CIV\NON_CAD\REPORTS\TIR\20190221 Rpt (TIR) 2190112.10.docx Technical Information Report 2940, 2960, 2980, and 2990 East Valley Road Renton, WA 98057 2190112.10 Appendix A Exhibits A-1 .................... Vicinity Map A-2 .................... TIR Worksheet A-3 .................... Developed Conditions Map A-4 .................... Drainage Basin Map 2215 North 30th Street, Suite 300, Tacoma, WA 98403 253.383.2422 TEL 253.383.2572 FAX JOB NO: DATE: RENTON EAST VALLEY ROAD VICINITY MAP SCALE: 1" = 1/4 MILE (1320')EX-1 2/20/17 2160915.10 SW 34TH ST SW 27TH ST SW 23RD ST LIND AVE SWSW 19TH ST 167 167OAKESDALE AVE NW515 515 515 E VALLEY RDSITE TALBOT RD SSW 29TH ST A-1 Compton Lumber Co 3847 1st Ave S, Seattle, WA 98134 Todd Sawin AHBL, Inc. 253.383.2422 2940, 2960, 2980, & 2990 E Valley Rd Renton, WA 98057 Compton Lumber Renton 30 23 N 05 E February 2016 February 2016 A-2 Black River Water Subbasin The City of Renton Peak Flow Rate Control Standard and Enhanced Basic Water Quality Existing Category III Wetland east of site Tu 0-1%Moderate Ur N/A N/A Existing Category III Wetland East Valley Road public stormwater system 1 12.22.2016 TBD TBD Peak Rate Flow Control Standard Commercail Conveyance pipes, catch basins, Filterra units, etc. Filterra 10' BUILDING SETBACK EXISTING WETLAND BOUNDARY COVERED LUMBER SALES NEW DRIVEWAY APPROACH NEW DRIVEWAY APPROACH T EAST VALLEY ROADEAST VALLEY ROADSW 27TH ST56.25' WETLAND BUFFER PROPOSED BUILDING 26' 26' 26' 18'26' R25' R25' 9' 7'(TYP) (TYP) (TYP) (TYP) (TYP) 9'(TYP) (TYP) PARCEL BOUNDARY LINE LUMBER RACKS PARCEL BOUNDARY LINE S89° 45' 25"E 406.80' S89° 39' 04"E 167.06'S1° 49' 52"W108.04'S89° 39' 04"E 452.25'S1° 49' 52"W658.54'S89° 45' 25"E 361.01'S1° 49' 52"W658.54'S89° 45' 25"E 321.19'S9° 28' 54"E628.23'MATCH EXISTING MATCH EXISTING 10' BUILDING SETBACK 15' BUILDING SETBACK EXISTING BUILDING TO BE REMOVED EXISTING BUILDING TO BE REMOVED EXISTING BUILDING TO BE REMOVED R4.5' PEDESTRIAN WALKING PATH ROOF OVERHANG 8' 10' 3' 8' 6' MATCH EXISTING NEW DRIVEWAY APPROACH NEW DRIVEWAY APPROACH LEGEND EXISTING PROPOSED TAX PARCEL NUMBER: PROJECT ADDRESS: ZONING: JURISDICTION: PARCEL ACREAGE: 3023059099 2980 EAST VALLEY RD RENTON, WA 98057 CA CITY OF RENTON 80,199 S.F. LEGAL DESCRIPTION BASIS OF BEARING VERTICAL DATUM PROJECT INFORMATION IF WORKERS ENTER ANY TRENCH OR OTHER EXCAVATION FOUR OR MORE FEET IN DEPTH THAT DOES NOT MEET THE OPEN PIT REQUIREMENTS OF WSDOT SECTION 2-09.3(3)B, IT SHALL BE SHORED AND CRIBBED. THE CONTRACTOR ALONE SHALL BE RESPONSIBLE FOR WORKER SAFETY AND AHBL ASSUMES NO RESPONSIBILITY. ALL TRENCH SAFETY SYSTEMS SHALL MEET THE REQUIREMENTS OF THE WASHINGTON INDUSTRIAL SAFETY AND HEALTH ACT, CHAPTER 49.17 RCW. THE LOCATIONS OF EXISTING UNDERGROUND UTILITIES ARE APPROXIMATE ONLY AND HAVE NOT BEEN INDEPENDENTLY VERIFIED BY THE OWNER OR ITS REPRESENTATIVE. THE CONTRACTOR SHALL DETERMINE THE EXACT LOCATION OF ALL EXISTING UTILITIES BEFORE COMMENCING WORK AND AGREES TO BE FULLY RESPONSIBLE FOR ANY AND ALL DAMAGES THAT HAPPEN DUE TO THE CONTRACTOR'S FAILURE TO LOCATE EXACTLY AND PRESERVE ANY AND ALL UNDERGROUND UTILITIES. AHBL ASSUMES NO LIABILITY FOR THE LOCATION OF UNDERGROUND UTILITIES. FILL MATERIAL SHALL NOT CONTAIN PETROLEUM PRODUCTS, OR SUBSTANCES WHICH ARE HAZARDOUS, DANGEROUS, TOXIC, OR WHICH OTHERWISE VIOLATE ANY STATE, FEDERAL, OR LOCAL LAW, ORDINANCE, CODE, REGULATION, RULE, ORDER, OR STANDARD. UTILITY NOTE FILL SPECIFICATION TRENCH NOTE THE EXISTING CULTURAL AND TOPOGRAPHIC DATA SHOWN ON THESE DRAWINGS HAS BEEN PREPARED, IN PART, BASED UPON INFORMATION FURNISHED BY OTHERS. WHILE THIS INFORMATION IS BELIEVED TO BE RELIABLE, AHBL CANNOT ENSURE ACCURACY AND THUS IS NOT RESPONSIBLE FOR THE ACCURACY OF THAT INFORMATION OR FOR ANY ERRORS OR OMISSIONS WHICH MAY HAVE BEEN INCORPORATED INTO THESE DRAWINGS AS A RESULT. TOPOGRAPHIC NOTE N GRAPHIC SCALE 0 40 80 1" = 40 FEET 20 ARCHITECT: SURVEYOR: AHBL 2215 N 30TH ST TACOMA, WA 98403 PHONE: 253.383.2422 CONTACT: DEAN ROBINSON, PLS RONHOVDE ARCHITECTS LLC 14900 INTERURBAN AVE S, SUITE 138 TUKWILA, WA 98168 CONTACT: LES SEIFERT PHONE: 206.859.5500 EMAIL: les@ronhovdearchitects.com OWNER/APPLICANT: COMPTON LUMBER CO 3847 1ST AVE S SEATTLE WA 98134 GEOTECHNICAL ENGINEER: TERRA ASSOCIATES, INC. 1220 113TH AVENUE NE, STE. 130 KIRKLAND, WA 98034 PHONE: 425.821.7777 CONTACT: TED SCHEPPER EMAIL: TSCHEPPER@TERRA-ASSOCIATES.COM 3023059091 2990 EAST VALLEY RD RENTON, WA 98057 CA CITY OF RENTON 18,042 S.F. 3023059098 2960 EAST VALLEY RD RENTON, WA 98055 CA CITY OF RENTON 88,299 S.F. 3023059096 2940 EAST VALLEY RD RENTON, WA 98057 CA CITY OF RENTON 68,220 S.F. PER FIRST AMERICAN TITLE COMPANY ORDER NO. NCS-827513-WA1 DATED DECEMBER 8, 2016 PARCEL A: THE NORTH 200 FEET OF THAT PORTION OF THE NORTH HALF OF THE SOUTHWEST QUARTER OF THE NORTHEAST QUARTER OF SECTION 30, TOWNSHIP 23 NORTH, RANGE 5 EAST, W.M., IN KING COUNTY, WASHINGTON, LYING WEST OF PRIMARY STATE HIGHWAY NO. 5 AS ESTABLISHED BY DEED RECORDED UNDER RECORDING NO. 5346369; EXCEPT THE WEST 30 FEET THEREOF CONVEYED TO THE STATE OF WASHINGTON FOR ROAD PURPOSES BY DEED RECORDED UNDER RECORDING NO. 1079782. PARCEL B: THE SOUTH 230 FEET OF THE NORTH 430 FEET OF THAT PORTION OF THE NORTH HALF OF THE SOUTHWEST QUARTER OF THE NORTHEAST QUARTER OF SECTION 30, TOWNSHIP 23 NORTH, RANGE 5 EAST, W.M., IN KING COUNTY, WASHINGTON, LYING WEST OF PRIMARY STATE HIGHWAY NO. 5 AS ESTABLISHED BY DEED RECORDED UNDER RECORDING NO. 5346369; EXCEPT THE WEST 30 FEET THEREOF CONVEYED TO THE STATE OF WASHINGTON FOR ROAD PURPOSES BY DEED RECORDED UNDER RECORDING NO. 1079782. PARCEL C: THE NORTH HALF OF THE SOUTHWEST QUARTER OF THE NORTHEAST QUARTER OF SECTION 30, TOWNSHIP 23 NORTH, RANGE 5 EAST, W.M., IN KING COUNTY, WASHINGTON, LYING WEST OF PRIMARY STATE HIGHWAY NO. 5 AS ESTABLISHED BY DEED RECORDED UNDER RECORDING NO.5346369; EXCEPT THE WEST 30 FEET THEREOF CONVEYED TO THE STATE OF WASHINGTON FOR ROAD PURPOSES BY DEED RECORDED UNDER RECORDING NO. 1079782; AND EXCEPT THE NORTH 430 FEET THEREOF; AND EXCEPT THE EAST 167 FEET OF THE WEST 197 FEET OF THE SOUTH 108 FEET OF SAID NORTH HALF OF THE SOUTHWEST QUARTER OF THE NORTHEAST QUARTER OF SAID SECTION. PARCEL D: THE EAST 167 FEET OF THE WEST 197 FEET OF THE SOUTH 108 FEET OF THE NORTH HALF OF THE SOUTHWEST QUARTER OF THE NORTHEAST QUARTER OF SECTION 30, TOWNSHIP 23 NORTH, RANGE 5 EAST, W.M., IN KING COUNTY, WASHINGTON. NAVD 1988 VERTICAL DATUM ON ORTHOMETRICALLY CORRECTED GPS OBSERVATIONS USING WSRN AND GEOID 2012A. VERIFIED CITY OF RENTON 230 (CASE MONUMENT AT S 23RD ST AND WILLIAMS AVE CUL DE SAC) ELEV: 230.75 NAD 1983 WASHINGTON STATE PLANE NORTH PROJECTION, BASED ON GPS OBSERVATIONS USING WSRN AND GEOID 2012A. UNITS OF MEASUREMENT ARE US SURVEY FEET. VERIFIED CITY OF RENTON 230 (CASE MONUMENT AT S 23RD ST AND WILLIAMS AVE CUL DE SAC) P T W W FOUND MONUMENT AS NOTED NAIL AND WASHER SET REBAR AND CAP FOUND PROPERTY CORNER BOLLARD MAIL BOX SIGN AS NOTED SOIL BORE SANITARY SEWER CLEANOUT SANITARY SEWER MANHOLE STORM CLEANOUT STORM CATCH BASIN STORM MANHOLE GAS VALVE UTILITY POWER POLE JUNCTION BOX POWER MANHOLE POWER METER LUMINAIRE COMMUNICATIONS MANHOLE TELEPHONE RISER TELEPHONE VAULT BLOW OFF VALVE FIRE HYDRANT HOSE BIB IRRIGATION CONTROL VALVE WATER METER WATER MANHOLE POST INDICATOR VALVE WATER VALVE WATER VAULT U-UNKNOWN DECIDUOUS TREE POWER VAULT HB STORM LINE SEWER LINE WATER LINE GAS LINE ELECTRICAL LINE COMMUNICATION LINE OVERHEAD UTILITIES FENCE ASPHALT CONCRETE WETLAND FIRE SERVICE LINE ROOF DRAIN LINE SW 27TH ST E VALLEY RDSW 23RD ST OAKESDALE AVE SWLIND AVE SWHIGHWAY 167515 515 TALBOT RD SS 23RD ST S 31ST ST SITE N VICINITY MAP SCALE: 1" = 1/4 MILE (1320') AHBL, INC. 2215 NORTH 30TH STREET - SUITE 300 TACOMA, WA 98403 PHONE: 253.383.2422 CONTACT: TODD SAWIN, P.E. EMAIL: TSAWIN@AHBL.COM CIVIL ENGINEER: LANDSCAPE AREA Know what's below. before you dig.Call R SOUNDVIEW CONSULTANTS LLC 2907 HARBORVIEW DRIVE, SUITE D GIG HARBOR, WA 98335 PHONE: 253.514.8952 CONTACT: JEREMY DOWNS EMAIL: JEREMY@SOUNDVIEWCONSULTANTS.COM WETLAND BIOLOGIST: CITY OF RENTON IN COMPLIANCE WITH CITY OF RENTON STANDARDSAAANNNNNNN COMPTON LUMBER RENTON A-NNNNNNN TEL FAX www.ahbl.comWEBTELFAXwww.ahbl.comWEBTELFAXwww.ahbl.comWEB 2215 North 30th Street, Suite 300 Tacoma, WA 98403 253.383.2422TEL 253.383.2572FAX www.ahbl.comWEB TACOMA SEATTLE SPOKANE TRI-CITIES EXISTING PARCEL TO BE MAINTAINED DURING CONSTRUCTION PARKING REQUIREMENTS STALLS GENERAL OFFICE = 10,000 SF 20 RETAIL/ WHOLESALE SALES (SHOWROOM) = 10,000 SF 25 WAREHOUSE= 30,000 SF 20 OUTDORR SALES = 31515 SF 16 TOTAL 81 PARKING PROVIDED TOTAL 99 C0.1 1 SITE PLAN COVER SHEET TEAST VALLEY ROAD EAST VALLEY ROAD SW 27TH ST WASHING T O N S T A T E R O U T E 1 6 7 CONNECT TO EXISTING WATER MAIN CONNECT TO EXISTING WATER MAIN FDC WATER METER PIV PROPOSED FIRE HYDRANT 12" WATER LOOP CL52 DI CONNECT TO EXISTING SEWER MAIN 6" PVC SEWER STUB @ 2% MIN 1 2 3 4 TEL FAX www.ahbl.comWEBTELFAXwww.ahbl.comWEBTELFAXwww.ahbl.comWEB 2215 North 30th Street, Suite 300 Tacoma, WA 98403 253.383.2422TEL 253.383.2572FAX www.ahbl.comWEB TACOMA SEATTLE SPOKANE TRI-CITIES 6 TCSDJHDJH 03.11.2019 LAND USE 2190112.10 14900 INTERURBAN AVE S, SUITE 138 TUKWILA, WA 98168 CONTACT: MR. LES SEIFERT EMAIL: les@ronhovdearchitects.com RONHOVDE ARCHITECTS LLC COMPTON LUMBER RENTON A PORTION OF THE SW 1/4 OF THE NE 1/4 OF SEC. 30, TWN. 23 N., RGE. 05 E. W.M. CITY OF RENTON, KING COUNTY, WASHINGTON. COMPTON LUMBER RENTON GRAPHIC SCALE 0 30 60 1" = 30 FEET 15 N15.00' WATER EASEMENT DATE: March 11, 2019 FILENAME: Q:\2019\2190112\10_CIV\CAD\2190112-SH-UTIL.dwg C2.0 5 UTILITY SHEET EXISTING 12" WATER (W-0304) MAXIMUM FLOWRATE 5,000 GPM STATIC PRESSURE AROUND 75 PSI AT EL:18 EXISTING FIRE HYDRANT EXISTING FIRE HYDRANT EXISTING WATER METER AND SERVICE TO BE ABANDONED EXISTING WATER METER AND SERVICE TO BE ABANDONED SITE ADDRESS 2940, 2960, 2980, AND 2990 EAST VALLEY ROAD RENTON, WA 98057 PACEL NO. 3023059103 PACEL NO. 3023059085 PACEL NO. 3023059091 PACEL NO. 3023059099 PACEL NO. 3023059098 PACEL NO. 3023059096 SITE COVERAGE AREAS NORTH BASIN = .70 AC SOUTH BASIN = 1.15 AC PERVIOUS AREA = 1.37 AC WETLAND = 0.16 AC ROOF = .90 AC TOTAL = 4.28 AC A-4 Technical Information Report 2940, 2960, 2980, and 2990 East Valley Road Renton, WA 98057 2190112.10 Appendix B Exhibits B-1 .................... Geotechnical Report by Terra Associates, Inc., January 24, 2017 B-2 .................... NRCS Soil Survey B-3 .................... Wetland and Fish and Wildlife Habitat Assessment and Restoration Plan by Soundview Consultants LLC, June 2017 B-4 .................... Downstream Analysis Map SITE Environmental Earth Sciences Terra Associates, Inc. Consultants in Geotechnical Engineering Geology and Figure 1 VICINITY MAP 0 2000 4000 APPROXIMATE SCALE IN FEET REFERENCE: http://www.wsdot.wa.gov/data/tools/geoportal/ ACCESSED 1/20/17 Proj.No. T-7563 Date: JAN 2017 RENTON, WASHINGTON E VALLEY ROAD INDUSTRIAL © 2017 Microsoft Corporation © 2010 NAVTEQ © AND B-1 B-2 B-3 B-4 B-5 B-6 REFERENCE: REFERENCE ONLY AND SHOULD NOT BE USED FOR DESIGN OR CONSTRUCTION PURPOSES. DIMENSIONS ARE APPROXIMATE. IT IS INTENDED FOR NOTE: THIS SITE PLAN IS SCHEMATIC. ALL LOCATIONS AND LEGEND: 0 100 200 APPROXIMATE SCALE IN FEET APPROXIMATE BORING LOCATION SITE PLAN PROVIDED BY BING MAPS. Environmental Earth Sciences Terra Associates, Inc. Consultants in Geotechnical Engineering Geology and EXPLORATION LOCATION PLAN Figure 2Proj.No. T-7563 Date: JAN 2017 RENTON, WASHINGTON E VALLEY ROAD INDUSTRIAL NOT TO SCALE 1. NOTES: 2. 4. 3. 5. 7. 6. 8. 9. PLASTIC COUPLINGS. PLASTIC PROTECTIVE SLEEVE SHOULD EXTEND AT LEAST 1" ABOVE TOP OF FILL SURFACE. STEEL MARKER ROD SHOULD EXTEND AT LEAST 6" ABOVE TOP OF PLASTIC PROTECTIVE SLEEVE. ADDITIONAL SECTIONS OF PLASTIC PROTECTIVE SLEEVE CAN BE CONNECTED WITH PRESS-FIT ADDITIONAL SECTIONS OF STEEL ROD CAN BE CONNECTED WITH THREADED COUPLINGS. PLASTIC TUBING. SLEEVE IS NOT ATTACHED TO ROD OR BASE. PROTECTIVE SLEEVE SURROUNDING MARKER ROD SHOULD CONSIST OF 2" DIAMETER MARKER ROD IS ATTACHED TO BASE BY NUT AND WASHER ON EACH SIDE OF BASE. MARKER ROD IS 1/2" DIAMETER STEEL ROD THREADED AT BOTH ENDS. BEDDING MATERIAL, IF REQUIRED, SHOULD CONSIST OF CLEAN COARSE SAND. BASE CONSISTS OF 3/4" THICK, 2'x2' PLYWOOD WITH CENTER DRILLED 5/8" DIAMETER HOLE. SURCHARGE OR FILLOR FILL SURCHARGE PROTECTIVE SLEEVE STEEL ROD HEIGHT VARIES (SEE NOTES) Environmental Earth Sciences Terra Associates, Inc. Consultants in Geotechnical Engineering Geology and SETTLEMENT MARKER DETAIL Figure 3Proj.No. T-7563 Date: JAN 2017 RENTON, WASHINGTON E VALLEY ROAD INDUSTRIAL 12" COMPACTED STRUCTURAL FILL EXCAVATED SLOPE (SEE REPORT TEXT FOR APPROPRIATE INCLINATIONS) SLOPE TO DRAIN 12" MINIMUM 3/4" MINUS WASHED GRAVEL 3" BELOW PIPE 12" OVER PIPE 4" DIAMETER PERFORATED PVC PIPE SEE NOTE 6"(MIN.) NOT TO SCALE NOTE: MIRADRAIN G100N PREFABRICATED DRAINAGE PANELS OR SIMILAR PRODUCT CAN BE SUBSTITUTED FOR THE 12-INCH WIDE GRAVEL DRAIN BEHIND WALL. DRAINAGE PANELS SHOULD EXTEND A MINIMUM OF SIX INCHES INTO 12-INCH THICK DRAINAGE GRAVEL LAYER OVER PERFORATED DRAIN PIPE. Environmental Earth Sciences Terra Associates, Inc. Consultants in Geotechnical Engineering Geology and TYPICAL WALL DRAINAGE DETAIL Figure 4Proj.No. T-7563 Date: JAN 2017 RENTON, WASHINGTON E VALLEY ROAD INDUSTRIAL Soil Map—King County Area, Washington Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 5/10/2017 Page 1 of 352558505255870525589052559105255930525595052559705255990525601052560305256050525607052560905256110525613052558705255890525591052559305255950525597052559905256010525603052560505256070525609052561105256130558920558940558960558980559000559020559040559060559080 558920 558940 558960 558980 559000 559020 559040 559060 559080 47° 27' 21'' N 122° 13' 6'' W47° 27' 21'' N122° 12' 57'' W47° 27' 12'' N 122° 13' 6'' W47° 27' 12'' N 122° 12' 57'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 10N WGS84 0 35 70 140 210 Feet 0 10 20 40 60 Meters Map Scale: 1:794 if printed on B portrait (11" x 17") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: King County Area, Washington Survey Area Data: Version 12, Sep 8, 2016 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Aug 31, 2013—Oct 6, 2013 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Soil Map—King County Area, Washington Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 5/10/2017 Page 2 of 3 Map Unit Legend King County Area, Washington (WA633) Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI Tu Tukwila muck 4.1 63.6% Ur Urban land 2.4 36.4% Totals for Area of Interest 6.5 100.0% Soil Map—King County Area, Washington Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 5/10/2017 Page 3 of 3 WETLAND AND FISH AND WILDLIFE HABITAT ASSESSMENT AND RESTORATION PLAN EAST VALLEY ROAD JUNE 2017 WETLAND AND FISH AND WILDLIFE HABITAT ASSESSMENT AND RESTORATION PLAN EAST VALLEY ROAD JUNE 22, 2017 PROJECT LOCATION 2960 EAST VALLEY ROAD RENTON, WA 98057 PREPARED FOR LATITUDE DEVELOPMENT 1801 WEST VALLEY HIGHWAY NORTH, SUITE 101 AUBURN, WA 98001 PREPARED BY SOUNDVIEW CONSULTANTS LLC 2907 HARBORVIEW DRIVE, SUITE D GIG HARBOR, WA 98335 (253) 514-8952 Soundview Consultants LLC i June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Executive Summary Soundview Consultants LLC (SVC) has been assisting Latitude Development (Applicant) with wetland delineation and fish and wildlife habitat assessment efforts for a proposed 35,000 square foot lumber distribution facility and retail center at 2960 East Valley Road in Renton, Washington. The subject property is composed of four parcels and is currently developed with a lumber distribution facility, a car storage and wrecking yard, and associated structures for a towing company. The subject property is situated in the Southwest ¼ of the Northwest ¼ of Section 30, Township 23 N, Range 05 E, W.M. (King County Tax Parcel Numbers 3023059096, 3023059098, 3023059099, and 3023059091). SVC investigated the subject property for the presence of potentially-regulated wetlands, waterbodies, fish and wildlife habitat, and priority species in winter of 2016. The site investigations identified one wetland (Wetland A) located on the eastern border of the subject property and one non-regulated drainage ditch (Drainage Z) located on the southern property boundary. Wetland A is classified as a Category III wetland and requires a standard 75-foot buffer which can be reduced by 25 percent to 56 feet through restoration measures. Wetland A extends offsite to the north and south along the eastern boarder of the subject property. Drainage Z is an intentionally created feature which is non- regulated per Renton Municipal Code (RMC) 4-3-050.G.7.b, which exempts waters that are considered “intentionally created”, as supported by historical imagery. The proposed development is separated from the critical areas onsite by a pre-existing, intervening, lawfully created structure and other substantial improvement (paved surface and 6-foot high solid fence, existing industrial uses) along the eastern and southern border of the subject property, and should be except from critical area buffers per RMC4-3-050.B.1.g; however, the applicant is proposing buffer restoration. There is an additional wetland approximately 275 feet from the subject property across Highway 167 which the project will not affect and the critical areas buffer is separated by Highway 167. The project was carefully designed in order to avoid and minimize impacts to sensitive areas to the greatest extent feasible. The proposed project must develop a stormwater pond in order to satisfy state and local requirements. The proposed stormwater pond will be located outside of any critical areas in the southeast corner of the subject property, further separating Wetland A from the proposed building. The buffer for Wetland A must be reduced to accommodate this stormwater pond’s spatial needs. The project proposes a reduced wetland buffer of 25 percent to 56 feet with restoration actions to the buffer area to offset this reduction while providing adequate protection of the wetland. As the current condition of the buffer consists of paved surfaces, the buffer restoration measures will provide better protection for the wetland and overall ecological benefit to the watershed to result in a net increase in habitat and water quality functions. These restoration actions would not occur without the buffer reduction. The summary table below identifies regulation by different agencies. Wetland/ Drainage Name Size (Onsite) Category1 /Type Regulated Under Renton Municipal Code 4-3-0502 Regulated Under RCW 90.48 Regulated Under Clean Water Act Wetland A ~8,333 sq. ft. onsite Category III Yes Yes Likely Drainage Z ~141 linear ft. N/A No No Not Likely Notes: 1 Current Washington State Department of Ecology (Hruby, 2014) and RMC 4-3-050.G.2 wetland rating. 2 Per RMC 4-3-050. Soundview Consultants LLC ii June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Table of Contents Chapter 1. Introduction ................................................................................................................................... 1 Chapter 2. Proposed Project ........................................................................................................................... 2 2.1 Project Location ................................................................................................................................ 2 2.2 Project Description ........................................................................................................................... 2 Chapter 3. Methods .......................................................................................................................................... 4 Chapter 4. Existing Conditions....................................................................................................................... 5 4.1 Landscape Setting .............................................................................................................................. 5 4.2 Historical Landscape Setting ........................................................................................................... 5 4.3 Topography and Drainage Basin .................................................................................................... 6 4.4 Wetland Inventories .......................................................................................................................... 6 4.5 Soils ..................................................................................................................................................... 6 4.6 Vegetation .......................................................................................................................................... 7 4.7 Priority Habitats and Species ........................................................................................................... 7 4.8 Precipitation ....................................................................................................................................... 7 Chapter 5. Results ............................................................................................................................................. 8 5.1 Wetlands ............................................................................................................................................. 8 5.2 Drainages .......................................................................................................................................... 11 5.3 Off-Site Critical Areas .................................................................................................................... 12 Chapter 6. Regulatory Considerations ......................................................................................................... 13 6.1 Local Regulations .................................................................................................................................. 13 6.2 State and Federal Considerations .................................................................................................. 13 Chapter 7. Buffer Reduction and Restoration Plan ................................................................................... 15 7.1 Description of Impacts ........................................................................................................................ 15 7.2 Sequencing ............................................................................................................................................. 15 7.3 Restoration Strategy .............................................................................................................................. 16 7.4 Measures to Minimize Impacts ........................................................................................................... 17 7.5 Restoration Goals, Objectives, and Performance Standards .......................................................... 17 7.6 Plant Materials and Installation ........................................................................................................... 18 7.7 Conceptual Maintenance & Voluntary Monitoring Plan ................................................................ 22 7.8 Voluntary Reporting ............................................................................................................................. 23 7.9 Contingency Plan .................................................................................................................................. 23 Chapter 8. Closure .......................................................................................................................................... 25 Chapter 9. Qualifications ............................................................................................................................... 26 Chapter 10. References .................................................................................................................................. 27 Figures Figure 1. Project Vicinity Map. ................................................................................................................. 2 Figure 2. Aerial Photograph of Subject Property. .................................................................................. 5 Soundview Consultants LLC iii June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Tables Table 1. Precipitation Summary ................................................................................................................ 7 Table 2. Wetland Summary. ....................................................................................................................... 8 Table 3. Wetland A Summary ................................................................................................................... 9 Table 4. Functions and Values of Wetland A. ...................................................................................... 10 Table 5. Drainage Z Summary. ............................................................................................................... 12 Appendices Appendix A — Methods and Tools Appendix B – Background Information Appendix C – Site Plans Appendix D – Data Forms Appendix E – Wetland Rating Form Appendix F – Qualifications Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 1 Chapter 1. Introduction Soundview Consultants LLC (SVC) has been assisting Latitude Development (Applicant) with wetland delineation and fish and wildlife habitat assessment efforts for a proposed 35,000 square foot lumber distribution facility and retail center at 2960 East Valley Road in Renton, Washington. The subject property is composed of four parcels and is currently developed with a lumber distribution facility, a car storage and wrecking yard, and associated structures for a towing company. The subject property is situated in the Southwest ¼ of the Northwest ¼ of Section 30, Township 23 N, Range 05 E, W.M. (King County Tax Parcel Numbers 3023059096, 3023059098, 3023059099, and 3023059091). The purpose of this wetland delineation and fish and wildlife habitat assessment report is to document the presence of potentially-regulated wetlands, fish and wildlife habitat, and/or priority species on or near the subject property; assess potential impacts to any such critical areas and/or species from the proposed project; and provide impact avoidance and management recommendations. This report provides conclusions and recommendations regarding: • Site description, project description, and area of assessment; • Identification, delineation, and assessment of potentially-regulated wetlands and other hydrologic features within the vicinity of the proposed project; • Identification and assessment of potentially-regulated fish and wildlife habitat and/or priority species located on or near the subject property; • Standard buffer recommendations, building setbacks, and development limitations; • Existing conditions site map detailing identified critical areas and standard buffers; • Proposed site plan with proposed project details; • Documentation of impact avoidance and minimization measures; • Buffer reduction plan with buffer restoration actions; and • Supplemental information necessary for local regulatory review. Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 2 Chapter 2. Proposed Project 2.1 Project Location The proposed project is located at 2960 East Valley Road in Renton, Washington. The subject property is situated in the Southwest ¼ of the Northwest ¼ of Section 30, Township 23 N, Range 05 E within the City of Renton (King County Tax Parcel Numbers 3023059096, 3023059098, 3023059099, and 3023059091). To access the site from Highway 405 East, take Exit 2 East and continue for 0.1 miles. Keep left at the form and then follow signs for WA-167 North/Renton and merge onto WA-167 North and proceed for 0.5 miles. Use the left two lanes to stay on WA-167 and continue for 0.2 miles. Turn left onto Southwest Grady Way and proceed for 0.3 miles. Turn left onto Lind Avenue Southwest and continue for 0.3 miles. Turn left at the 2nd cross street onto Southwest 16th Street and proceed for 0.2miles. Continue onto East Valley Road for 0.8 miles. The site destination will be on the left. Figure 1. Project Vicinity Map. 2.2 Project Description The project proposes to provide a new lumber distribution and retail facility and utilize an existing lumber retail and distribution facility onsite near West Valley Highway consistent with the City of Renton zoning and nearby uses. The proposed project includes demolition of existing structures, Subject Property (Approximate) Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 3 removal of scrap and debris associated with the previous land use, and clearing and grading for construction of one 35,000-square foot distribution and retail building with associated infrastructure including parking areas, utilities, and stormwater facilities. The project was carefully designed in order to avoid and minimize impacts to sensitive areas to the greatest extent feasible. The proposed project must develop a stormwater pond in order to satisfy state and local requirements. The proposed stormwater pond will be located outside of any critical areas in the southeast corner of the subject property. The buffer for an onsite wetland (Wetland A) must be reduced to accommodate this stormwater pond’s spatial needs. The project proposes restoration actions to the buffer area to offset this reduction while providing adequate protection of the wetland. As the current condition of the buffer consists of paved surfaces that were established and maintained under a prior land use, the buffer restoration measures will provide better protection for the wetland and overall ecological benefit to the watershed to result in a net increase in habitat and water quality functions. These restoration actions would not occur without the buffer reduction. A buffer reduction and restoration plan is discussed in Chapter 7 of this Report. Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 4 Chapter 3. Methods SVC investigated, assessed, and delineated wetlands, drainages, and other potentially-regulated fish and wildlife habitat within the subject property and identified potentially-regulated features within 200 feet of the subject property during December of 2016. All wetland determinations were made using observable vegetation, hydrology, and soils in conjunction with data from the U.S. Geographic Survey (USGS) topographic maps, the Natural Resources Conservation Service (NRCS) Soil Survey, National Wetlands Inventory (NWI), King County Geographic Information Services (GIS) data, City of Renton GIS data, U.S. Fish and Wildlife Service (USFWS), Washington State Department of Natural Resources (DNR), the Soil Survey of King County (Snyder et al., 1973), local precipitation data (NOAA), and various orthophotographic resources Wetland boundaries were determined using the routine approach described in the U.S. Army Corps of Engineers’ Wetlands Delineation Manual (USACE, 1987) and modified according to the guidelines established in the Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Western Mountains, Valleys, and Coast Region, Version 2.0 (USACE, 2010). Qualified SVC wetland scientists marked boundaries of onsite wetlands with orange surveyor’s flagging labeled alpha-numerically and tied to 3-foot lath or vegetation along the wetland boundary. Pink surveyor’s flagging was labeled alpha-numerically and tied to 3-foot lath or vegetation at formal sampling locations to mark the points where detailed data was collected. Additional tests pits were excavated at regular intervals inside and outside of the wetland boundaries to further confirm each delineation. SVC classified all wetlands using both the hydrogeomorphic (Brinson, 1993) and Cowardin (Cowardin, 1979) classification systems, and assessed wetlands using the Wetland Functions Characterization Tool for Linear Projects (WSDOT, 2000). Following classification and assessment, WSDOE-trained scientists rated and categorized all wetlands using the Washington State Wetlands Rating System for Western Washington (Hruby, 2014) and the definitions established in RMC 4-3-050.G.9. Drainages and surface water features were classified using the DNR Water Typing System as described in the Washington Administrative Code (WAC) Section 222-16 and the guidelines established in RMC 4-3-050.G.7. The fish and wildlife habitat assessment was conducted during the same site visits by qualified fish and wildlife biologists. Experienced biologists made visual observations using stationary and walking survey methods for both aquatic and upland habitats noting any special habitat features or signs of fish and wildlife activity. Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 5 Chapter 4. Existing Conditions 4.1 Landscape Setting The subject property is a highly disturbed industrial site that has been scraped, graded and paved under a prior land use. The site is currently a retail lumber and distribution facility, auto wrecking site, and storage yard, and contains four industrial service buildings. The subject property is bordered to the north by a large commercial office building, to the east by Highway 167, to the south by a vacant lot zoned for commercial use, and to the west by East Valley road with two large warehouse buildings beyond. Figure 2. Aerial Photograph of Subject Property. 4.2 Historical Landscape Setting Historical photographs were examined in order to determine the past uses of the subject property. The subject property has been in agricultural use since at least the 1930s. Aerial photographs from 1936 and 1940 indicate the subject property as agricultural farmland with row crops and plowing shown throughout the subject property, as well as the surrounding valley landscape. A road is depicted directly west of the subject property in the same orientation as the current East Valley Road. A 1964 aerial photograph depicts the subject property as cleared land with Highway 167 apparently under construction to the east. A potential linear drainage feature is depicted on the southern border of the subject property (see discussion of Drainage Z in Chapter 5 of this Report). A 1998 aerial photograph depicts the subject property as it appears in its current state with several industrial buildings, vehicle storage yards, and a wetland located on the eastern border. Historical aerial photographs are provided in Appendix B2. Subject Property (Approximate) Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 6 The King County hydrographic and topographic map (Appendix B3) depicts Panther Creek traversing through Wetland A in a west and then north direction; however, this feature is not depicted on the City of Renton GIS data, DNR stream typing map, or WDFW SalmonScape map. It is conceivable that this feature had continuous flow past the subject property historically, however, now it flows east of Highway 167 to the north. Maps and data are provided in Appendix B. 4.3 Topography and Drainage Basin The topography of the site is generally flat and at an elevation of approximately 20 feet above mean sea level. The subject property is located within Water Resource Inventory Area (WRIA) 9 - Duwamish-Green River Watershed. WRIA 9 is situated in southern Puget Sound and comprises most of southern King county. On its west side, it is bounded by Puget Sound and its east side includes portions of the Cascade Mountain range. WRIA 9 has a large amount of urban development and high population density on its west side. This watershed includes only one major river, the Duwamish- Green River which originates in the Cascade Mountains. The Green River is the source for much of the drinking water for the Tacoma area and includes the Howard A. Hanson Dam, which is used for flood control and reservoir purposes. The watershed includes various smaller streams such as Jenkins, Little Soos, Newaukum and Boundary creeks. 4.4 Wetland Inventories The City of Renton GIS map (Appendix B4) and USFWS NWI map (Appendix B5) identify a linear wetland located offsite along the eastern subject property boundary. Potential wetland areas are also documented greater than 200 feet east of the subject property, on the opposite side of Highway 167. 4.5 Soils The NRCS Soil Survey of King County identifies two soil series present on the subject property: Tukwila Muck (Tu) and Urban Land (Ur). The soil map is provided in Appendix B6. Below is a detailed description of the soil profiles. Tukwila muck (Tu) Tukwila muck occurs on zero to one percent slopes and is considered to have very poor drainage. It forms on floodplains with a parent material consisting of herbaceous organic material. In a typical profile, the surface layer consists of muck from 0 to 19 inches below ground surface (bgs). The subsurface layer consists of stratified diatomaceous earth to muck from 19 to 60 inches bgs. Tukwila Muck is listed as hydric on the King County Hydric Soils List (NRCS, 2001). Urban Land (Ur) According to the soil survey, urban land soil type exhibits high anthropogenic disturbance. The natural soil layers are disturbed and have three to twelve feet of added fill material to accommodate large commercial, industrial, and residential developments. The soil varies from gravelly sandy loam to gravelly loam in texture (NRCS, 1973). This is not listed as hydric soil on the King County Hydric Soils List (NRCS, 2001), nor the Hydric Soils List of Washington State (NRCS, 1995). While the NRCS soil survey depicts Tukwila Muck presence on the subject property and throughout the region of development to the north and south of the subject property, it is highly unlikely that this Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 7 soil is currently present in these locations due to the intensive development and historic manipulation in the area. 4.6 Vegetation Upland landscape consists of over-scraped, paved, and graded areas with the invasive Himalayan blackberry scattered throughout the site. Onsite wetland areas were characterized by red alder, red- osier dogwood, black cottonwood saplings, red-tinged bulrush, and cat tails with sparse reed canarygrass. The onsite drainage feature is dominated by invasive species such as field bindweed and Himalayan blackberry with lesser amounts of red alder. 4.7 Priority Habitats and Species The City of Renton GIS data does not identify any streams on the subject property. A Type F stream is located to the east of Highway 167 approximately 400 feet away from the subject property (Appendix B8). The DNR Stream Typing map does not identify any streams on or near the vicinity of the subject property (Appendix B7). The WDFW SalmonScape map does not identify any streams located on the subject property. 4.8 Precipitation Precipitation data was obtained from the National Oceanic and Atmospheric Administration (NOAA) weather station at the Seattle-Tacoma International Airport in order to obtain percent of normal precipitation during and preceding the investigation. A summary of data collected is provided in Table 1. Table 1. Precipitation Summary Date Day of1 Day Before1 1 Week Prior1 2 Weeks Prior1 Month To Date3 (Observed/ Normal) Water Year to Date 4 (Observed/ Normal) Percent of Normal (MTD/Water Year)5 12/15/16 T2 0.00 0.76 1.73 1.63/2.70 18.16/12.75 60/142 Notes: 1. Data obtained from the NOAA weather website at SeaTac International Airport http://w2.weather.gov/climate/xmacis.php?wfo=sew 2. Trace amounts. 3. Month-to-date value obtained from the first day of the onsite date visit month to the onsite date. 4. Water Year is precipitation from October 1 to the onsite date. 5. Percent of Normal shown for both the Month-to-Date and the Water Year. Precipitation for the December 2016 onsite visit was 60 percent of normal for the month-to-date and 142 percent of normal for the 2016/2017 water year. This precipitation data suggests that significantly high precipitation for the 2016/2017 water year may have caused some areas that are not normally wet to become saturated and/or inundated at the time of the site investigations due to higher than normal precipitation. Such conditions were considered in making professional wetland boundary determinations. Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 8 Chapter 5. Results 5.1 Wetlands The site investigation identified one potentially-regulated wetland (Wetland A) located on the eastern border of the subject property extending offsite to the north and south. One additional offsite wetland was also observed across Highway 167 approximately 275 from the subject property. SVC’s site investigation in the spring of 2017 consisted of walk-through surveys of all accessible areas on or within 300 feet of the subject property per RMC 4-3-050. The identified wetland contained indicators of wetland hydrology, hydric soils, and a predominance of hydrophytic vegetation according to current wetland delineation methodology. Wetland data forms are provided in Appendix D, and a wetland rating form is provided in Appendix E. Table 2 summarizes the wetland identified on the subject property, Table 2. Wetland Summary. Wetland Predominant Wetland Classification / Rating Wetland Size (acres) Buffer Width (feet)E CowardinA HGMB WSDOEC City of RentonD A PSS/EMH Depressional III III 0.23 56 Notes: A. Cowardin et al. (1979) and Federal Geographic Data Committee (2013), or National Wetland Inventory (NWI) Class based on vegetation: PEM = Palustrine Emergent; PSS = Palustrine Scrub-Shrub; Modifiers (-H) = Water Regime or Special Situations for a permanent flooding hydroperiod. B. Brinson, M. M. (1993). C. Ecology rating per Washington State Wetland Rating System for Western Washington – Revised Hruby (2014). D. RMC 04-03-050.G.9. definition (verified with Ecology 2014 rating forms). E. RMC 4-3-050.G.2. buffer width standards. F. RMC 4-3-050. I.1. buffer width reduction by 25 percent. Wetland A is located on the eastern boundary of the subject property extending offsite. Wetland A is 8,333 square-feet (0.17 acre) in size onsite, and has a permanently flowing outlet. Hydrology for Wetland A is provided by a seasonally high groundwater table, direct precipitation, and stormwater runoff from adjacent high intensity land uses with excess impervious surfaces. The dominant vegetation in this wetland is red alder saplings, Pacific willow, red osier dogwood, black cottonwood saplings, red-tinge bulrush, and reed canarygrass. Wetland A is a Palustrine Scrub-Shrub/Emergent, Permanently Flooded wetland. Under RMC 4-3-050.G.9, Wetland A is a Category III depressional wetland with a habitat score of 4 points. Under RMC 4-3-050.G.2 and RMC 4-3-050.I.1, Category III wetlands with a habitat score of 3-4 points and with a land uses other than low impact uses require a standard buffer of 75 feet which can be reduced by 25 percent through restoration measures. This rating is consistent with an accepted wetland rating for Wetland A for the adjacent property to the north for an application as recent as December 2016 (Appendix B10). Table 3 provides a detailed summary of Wetland A. Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 9 Table 3. Wetland A Summary Table 3. Wetland A Summary WETLAND A – INFORMATION SUMMARY Location: Along the eastern property boundary. Local Jurisdiction Renton WRIA 9 – Duwamish - Green Ecology Rating (Hruby, 2014)A III City of Renton RatingB III City Buffer WidthC 75 foot standard buffer Building Setback 15 feet Wetland Size 8,333 square feet (0.17 acres) onsite Cowardin ClassificationD PSS/EMH HGM ClassificationE Depressional Wetland Data Sheet(s) DP-1 Upland Data Sheet (s) DP-2 Boundary Flag color Orange Dominant Vegetation The dominant vegetation in this wetland are red alder saplings, Pacific willow, red osier dogwood, black cottonwood saplings, cattails, red-tinge bulrush, and reed canarygrass. Soils Mapped as Tukwila Muck. Hydric soil indicator A4 observed. Hydrology Hydrology for Wetland A is provided by surface sheet flow, direct precipitation, a seasonally-high groundwater table, and excess stormwater runoff from surrounding development Rationale for Delineation Wetland boundaries were determined by topographic drop and a transition to hydrophytic plant community. Rationale for Local Rating Wetland A is rated according to the Washington State Wetlands Rating System for Western Washington – Washington State Department of Ecology Publication No. 14-06-029, published October 2014 (Hruby, 2014) and guidelines established in the Renton Municipal Code 4-3-050.G.9. Wetland Functions Summary Water Quality Wetland A has the opportunity to retain sediments and pollutants from stormwater runoff associated with the nearby road and development. As this wetland is located in close proximity to a 303(d) waterway, it has relatively moderate capabilities of supporting water quality functions onsite. Wetland A’s score for Water Quality Functions using the 2014 method is moderate (6). Hydrologic Storage capacity is moderate due to its permanently ponded hydroperiod, therefore hydrologic function is limited to moderate reductions of surface flows during storm events. Wetland A’s score for Hydrologic Functions using the 2014 method is moderate (6). Habitat Habitat functions provided by the wetland may include limited small bird foraging and wetland associated amphibians and mammals due to its permanent ponding hydroperiod; however, minimal other habitat functions are provided due to the wetland being surrounded by development. Wetland A’s score for Habitat Functions using the 2014 method is low (4). Buffer Condition The buffer surrounding Wetland A is substantially impacted by adjacent industrial development and Highway 167. The onsite buffer is paved and maintained under a prior land use. Vegetation that partially surrounds consists primarily of Himalayan blackberry. The buffer provides no screening of the wetland from outside disturbances and little or no water quality enhancement. Notes: A. WSDOE rating according to Washington State Wetland Rating System for Western Washington – Hruby (2014). B. RMC (4-3-050.G.9), as amended. C. Recommended wetland buffer width with reduction modification according to RMC 4-3-050.D.5.c.iv. D. Cowardin et al. (1979) Federal Geographic Data Committee (2013) or NWI Class based on vegetation: PEM = Palustrine Emergent; PSS= Palustrine Scrub-Shrub Modifier (-H) = Water Regime or Special Situations for Permanent ponding. E. Brinson, M. M. (1993). Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 10 Wetland A Functions The wetland on the subject property may provide some water quality and hydrologic functions, such as limited stormwater retention and infiltration, water quality enhancement, and wildlife habitat. Wetland functions were evaluated using the Wetland Functions Characterization Tool for Linear Projects (BPJ) (WSDOT, 2000) in conjunction with the Western Washington Wetland Rating System - Revised (Hruby, 2014). Wetland A is moderately vegetated with two Cowardin classifications (scrub-shrub and emergent strata) and as such provides general habitat suitability due to the increased diversity in strata. Storage capacity is moderate due to the size of the wetland unit; therefore, hydrologic function is limited to minor reductions of surface flows during storm events. The wetland has the potential to retain sediments and pollutants and has the potential to provide moderate biofiltration. Habitat capacity is limited to small bird foraging and amphibian refugia, but lacks plant richness and quality functioning buffers. The wetland unit is long durational seasonally flooded and therefore provides the potential habitat for wetland-associated aquatic invertebrates, as well as habitat for amphibians. This wetland does not provide general fish habitat as there are no documented fish species associated with Wetland A. Table 4. Functions and Values of Wetland A. Function / ValueA Wetland A Water Quality Functions Sediment Removal x Nutrient and Toxicant Removal x Hydrologic Functions Flood Flow Alteration - Erosion Control and Shoreline Stabilization - Habitat Functions Production and Export of Organic Matter - General Habitat Suitability x Habitat for Aquatic Invertebrates x Habitat for Amphibians x Habitat for Wetland-Associated Mammals - Habitat for Wetland-Associated Birds - General Fish Habitat - Native Plant Richness - Special Characteristics Educational or Scientific Value - Uniqueness and Heritage - Notes: 1. “-“ Is the function is not present; “x” means that the function is present is of lower quality; and “+” means the function is present and is of higher quality. Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 11 Wetland A Buffer The upland buffer surrounding Wetland A is dominated by Himalayan blackberry, bull thistle, Canadian thistle, and morning glory. Non-native invasive species make up approximately 30 percent of the vegetative cover of the narrow and degraded onsite buffer. Most of the onsite buffer area consists of paved surfaces maintained under a prior land use. The eastern offsite border of Wetland A abuts Washington State Route 167. Wetland A is a Category III wetland with a low habitat score. Wetland A requires a 75-foot standard buffer based on high intensity land uses. An additional 15-foot building setback is also required from the edge of the wetland buffer (RMC 4-3-050.G.2 and RMC 4-3-050.I.1). This buffer and wetland rating is consistant with a prior accepted wetland rating for Wetland by a prior (2016) application (Appendix B10). 5.2 Drainages The site investigation identified one non-regulated unnamed drainage ditch located on the southern border of the subject property (Drainage Z). Drainage Z flows along the southern border of the subject property, traversing in an east to west direction and flowing into an approximate 24 inch culvert under East Valley Road, continuing west under other developments west of East Valley Road. Drainage Z is not recognized by the City of Renton GIS data, DNR stream typing map, or WDFW’s SalmonScape map. Historical photographs were examined to identify when Drainage Z was created. An aerial photograph from 1964 depicts a linear feature on the southern border of the subject property and in the same location and orientation as Drainage Z. Highway 167 is also apparently under construction in this 1964 historic aerial, suggesting that Drainage Z was artificially constructed to provide drainage for the new highway. Drainage Z provides a permanently flowing outlet for Wetland A but does not likely drain the entire Wetland A unit as Wetland A continues south and north along the west side of Highway 167. Drainage Z primarily drains adjacent uplands. According to RMC 4-3-050.G.7.b, waters that are considered “intentionally created” are not regulated, including irrigation ditches, grass-lined swales, and canals that do not meet the criteria for Type S, F, Np, or Ns waterbodies. As background data shows, purposeful creation is documented through historical aerial photograph research as the 1936 and 1940 historical aerial photographs illustrate the current drainage alignment in agricultural production, and the 1964 aerial photograph depicts the drainage intentionally created concurrently with the construction of Highway 167 (See Appendix B2 for historical aerial photographs). Therefore, Drainage Z should be considered an intentionally created feature. A summary of Drainage Z is provided in Table 5 below. Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 12 Table 5. Drainage Z Summary. STREAM INFORMATION SUMMARY Feature Name Drainage Z WRIA 9 – Duwamish - Green Local Jurisdiction City of Renton DNR Stream Type N/A Local Rating1 N/A Intentionally-created feature Buffer Width1 N/A Intentionally-created feature Building Setback N/A Documented Fish Use None Location of Feature Drainage Z is located on the southern border of the subject property, traversing in an east to west direction. Connectivity (where water flows from/to) Drainage Z likely originates from the east and flows west under East Valley Road. Documented Fish Species N/A Riparian/Buffer Condition The onsite buffer of the drainage is highly disturbed and dominated by invasive vegetation including reed canarygrass and Himalayan blackberry. The drainage is surrounded by paved surfaces under a prior land use. Notes: 1. RMC 4-3-050.G.7.b. 5.3 Off-Site Critical Areas Off-Site Wetlands Wetland A extends offsite of the subject property to the north and south along the eastern border of the subject property. One additional offsite wetland was observed 275 feet to the east of the of the subject property across Highway 167. The proposed development is separated from the offsite wetlands by a pre-existing, intervening, lawfully created structure and other substantial improvement (paved surface, Highway 167 and 6-foot high fencing) along the eastern and southern border of the subject property, and should be except from critical area buffers per RMC4-3-050.B.1.g; however, the applicant is proposing buffer restoration out of an abundance of caution. The potential offsite buffers would not encroach onto the subject property, and the proposed development should not affect any offsite critical areas. Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 13 Chapter 6. Regulatory Considerations The results of the investigation identified one potentially-regulated Category III wetland (Wetland A) and one non-regulated drainage ditch (Drainage Z) located on the subject property. The project proposes a reduced wetland buffer with restoration actions to the buffer area to compensate for the reduction. To optimize site use while conforming to development standards set forth by the City of Renton, a stormwater pond is proposed in the southeastern portion of the subject property. This chapter discusses the regulatory implications and considerations of the proposed project development. 6.1 Local Regulations The proposed project is designed to meet the City of Renton Critical Areas Regulations as outlined in RMC 4-3-050 for an enhanced buffer plan to compensate for the proposed buffer reduction and enhancement. The following section details how these codes are being met. 6.1.1 Wetland Buffer Requirements and Modifications Wetland A is a Category III with a low habitat score and requires a standard buffer width of 75 feet with an additional building set back of 15 feet (RMC 4-3-050.G.2). Per RMC 4-3-050.I.1, a buffer reduction is allowed by 25 percent, provided requirements are met pursuant to RMC 4-3-050.I.3, which would reduce the Wetland A buffer width to 56 feet. This is consistent with a prior accepted wetland Rating for Wetland A by the City of Renton (Appendix B10). A buffer restoration plan is outlined in Chapter 7 of this Report in order compensate for the reduction. The buffer restoration plan, as described in detail in Chapter 7, proposes removal of paved surfaces from the wetland buffer to provide an undulating topography revegetated with native plant species to help re-establish a more natural buffer area adjacent to the wetland. In fact, the value and benefit of the buffer restoration actions proposed will greatly exceed any minor impacts associated with reduction of the buffer. The buffer being restored is currently paved surface and only contains a few trees adjacent to the wetland. As a result, the proposed buffer reduction will result in no net loss of buffer or habitat functionality and the restoration actions will enhance buffer functions and values to better protect the wetland. 6.1.2 Non-Regulated Drainages Drainage Z is a linear drainage ditch intentionally created in an upland area. Drainage Z flows along the southern border of the subject property, traversing in an east to west direction and flowing into a culvert under East Valley Road. Historical aerials clearly depict that Drainage Z was artificially created sometime between 1940 and 1964, in concurrence with the construction of Highway 167. The drainage feature was likely intentionally created to direct stormwater away from the highway. Historical aerials of the subject property are provided in Appendix B2.According to RMC 4-3- 050.G.7.b, intentionally created irrigation ditches, grass-lined swales, and canals are not regulated features. 6.2 State and Federal Considerations The onsite Wetland A has a surface and/or subsurface connection to waters of the United States; therefore, this features is regulated under Section 404 of the CWA. However, as no direct impacts to Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 14 wetlands are proposed, permitting under USACE is not required at this time. The WSDOE also regulates wetlands and natural surface waters under RCW 90.48. The WSDOE does not, however, recognize non-wetland drainage swales and ephemeral/stormwater ditches excavated from uplands as features typically subject to regulation under RCW 90.48. Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 15 Chapter 7. Buffer Reduction and Restoration Plan The proposed buffer restoration plan for the project attempts to provide adequate protection of the wetland functions while allowing a 25 percent reduction of the buffer under RMC 4-3-050.I.3.a. Removal of paved surfaces will develop restored wetland function with increased hydraulic function and storage capacity, and planting of native vegetation and placement of large woody debris (LWD) will augment nature processes. All work is proposed with the goal of improving hydrologic, water quality, and habitat functionality of Wetland A and associated buffer. 7.1 Description of Impacts The project proposes a buffer reduction and restoration for Wetland A which will reduce the standard buffer by 25 percent to 56 feet. To optimize site use while conforming to the City of Renton’s development standards, the project proposes to construct the stormwater pond in the southeastern portion of the subject property between Wetland A and the proposed building, outside of the reduced Wetland A buffer. Impacts are expected to be minimal. Potential temporary minor impacts may occur with the removal of paved surfaces for buffer restoration or due to the development of the stormwater pond. As such, these developments add function and value by increasing water quality while also facilitating the growth for a healthy wetland buffer. Further, the current condition of the buffer consists of paved surfaces. Construction of the stormwater feature will further buffer the wetland from the proposed development, and without the proposed development the buffer would remain in its current state which is paved and maintained. Temporary impacts include potential minor excavation within the Wetland A buffer to facilitate nature buffer processes, as well as excavation outside of the reduced buffer for stormwater pond development. During construction activities, the project will implement all appropriate best management practices (BMPs) and temporary erosion and sediment control (TESC), which are measures to reduce potential temporary impacts due to grading actions. 7.2 Sequencing To meet the need of the proposed development, a new approximate 35,000 square foot building needs to be constructed. In addition, local building, fire, and site development regulations require additional parking access, storm, and fire services. The Wetland A buffer which is currently paved and maintained under a prior land use will need to be reduced to allow adequate infrastructure. The stormwater pond will be developed outside of the reduced buffer. Impacts to critical areas are being avoided through careful design, and the implementations of the restoration actions will result in an ecological lift from the current conditions of paved surfaces. Other than the proposed restoration actions, the project was carefully designed to avoid direct impacts to all onsite critical areas and buffers. Wetland A is constrained by Highway 167 to the east and paved surfaces onsite to the west, exhibiting no functional buffer within the surrounding areas onsite or offsite. Through careful planning efforts the proposed project avoids on-site impacts by locating the development away from Wetland A and provides buffer restoration actions to restore the currently non-existent buffer functionality of Wetland A. The restoration actions will achieve a net gain in critical area protections and improvement Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 16 in watershed functions. The buffer for Wetland A will be protected and restored per the specifications and plans presented herein. In addition, the project itself has been designed specifically to protect hydrology and water quality by locating stormwater treatment ponds between the project’s developed areas and Wetland A, thus providing additional buffering distance from facility operations and increasing buffer functionality over existing conditions. The proposed project provides comprehensive stormwater treatment and flow control to minimize impacts on hydrology, and silt fences and other TESC measures will be installed and maintained on the site to minimize construction impacts on sedimentation and water quality. 7.3 Restoration Strategy Buffer restoration is proposed to restore wetland habitat functionality and increase hydrologic function and storage capacity in an area currently degraded by industrial use. This restoration plan proposes to offset potential impacts associated with construction and to significantly expand storage capacity by removing paved surfaces, improve conveyance, facilitate natural processes, improve wildlife habitat complexity, and restore native vegetation and habitat structures and associated onsite buffers. The proposed actions to the buffer of Wetland A buffer will involve extensive removal of paved surfaces and fill to provide an undulating topography, removal of trash and non-native invasive plant species, planting native plant species using the plant list provided in Table 6-8 and Appendix C, and installation of a protective fence along the outer buffer edge. An approximate 2:1 cut will then be used to meet the existing grade adjacent to the stormwater pond. All grading will be rough to mimic natural topography, and upland hummocks will be strategically located to provide additional wildlife habitat areas. As some trees are currently located adjacent to the wetland, deciduous trees will be preserved where possible on hummocks. Additional wildlife habitat features, such as standing snags and LWD will be installed in select locations. These features will effectively screen Wetland A from disturbances and protect the wetland functions and values. The proposed project has been carefully designed to avoid direct impacts to Wetland A as a result of the proposed development and/or during wetland buffer restoration activities. As the buffer surrounding Wetland A is comprised of paved surfaces and existing anthropogenic impacts, the proposed restoration actions are anticipated to improve wetland buffer protections and internal wetland functions by establishing an overall net gain in buffer functionality, allowing for improvement over existing wetland protections and will function at a higher level than the standard buffer. Light intrusion into Wetland A will be minimized by directing lights away from the wetland, and traffic will be routed outside the adjusted wetland buffer to mitigate vehicle light intrusion. A selection of native plants will be installed along the outer perimeter of the wetland buffer to reduce the opportunity for physical intrusion into the buffer, and a fence will be installed along the perimeter of the critical area buffer. No unauthorized pesticide use will be permitted within the wetland or wetland buffer. As part of the construction plan, BMPs will be applied during construction to control dust and surface runoff. These measures demonstrate that construction and post-construction efforts are designed to maintain the buffer in a natural vegetative state while minimizing further impacts from the development or adjacent land use. Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 17 Restoration actions for the wetland buffer include, but may not be limited to, the following recommendations: • Removal of paved surfaces and trash and debris within the wetland buffer; • Pre-treat invasive plants with an herbicide approved by Washington Department of Agriculture, then grub to remove the invasive plants, and replant all cleared areas with using the native species outlined in Table 6-8 and Appendix C. Pre-treatment of the invasive plants should occur a minimum of two weeks prior to removal; • Replant all areas with native trees, shrubs, and groundcovers listed in Section 7.6.3, or substitutes approved by the responsible wetland scientist, to help retain soils, filter stormwater, and increase biodiversity; • An approved native seed mix will be used to seed the disturbed areas after planting; • Maintain and control invasive plants annually, at a minimum, or more frequently if necessary. Maintenance to reduce the growth and spread of invasive plants is not restricted to chemical applications but may include hand removal, if warranted; • Provide dry-season irrigation as necessary to ensure native plant survival; • Direct exterior lights away from the wetlands wherever possible; • Place all activities that generate excessive noise (e.g., generators and air conditioning equipment) away from the wetlands where feasible. 7.4 Measures to Minimize Impacts The proposed restoration plan is intended to provide increased wetland protections by maintenance or improvement of wetland buffer functions. Impacts to the wetland buffer are being minimized through careful planning efforts and project design. Restoration actions of disturbed areas within the wetland buffer should occur immediately after grading is complete. A concrete wash water collection basin should also be installed away from any onsite buffers prior to commencement of any construction activities requiring additional concrete work. TESC measures will be implemented that consist of high visibility fence installed around native vegetation along the perimeter of the reduced buffer, silt fencing between the graded areas and undisturbed buffer, plastic sheeting on stockpiled materials, and seeding of disturbed soils. These TESC measures should be installed prior to the start of development or restoration actions and actively managed for the duration of the project. All equipment staging and materials stockpiles should be kept out of the buffer, and the area will need to be kept free of spills and/or hazardous materials. Equipment will be kept in good working order free of leaks. All fill material and road surfacing should be sourced from upland areas onsite or from approved suppliers, and will need to be free of pollutants and hazardous materials. Construction materials along with all construction waste and debris should be effectively managed and stockpiled on paved surfaces and kept free of the remaining wetland buffer area. Following completion of the residence, the entire site should be cleaned and detail graded using hand tools wherever necessary, and TESC measures will need to be removed. 7.5 Restoration Goals, Objectives, and Performance Standards Approximately 32,577-square feet of wetland buffer will be reduced and restored in accordance to standards set forth in RMC 4-3-050.I.3.a. Restoration actions for the wetland buffer include, but may not be limited to, the following voluntary recommendations: Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 18 Goal 1 – Restore buffer function for Wetland A by establishing an approximately 56-foot wide functional buffer with associated habitat features. Objective 1 – Establish approximately 32,577 square feet of functional buffer area adjacent to Wetland A through the removal of paved surfaces. Performance Standard 1 – As measured from wetland boundary onsite, the total size of functional buffer area onsite will measure 32,577 square feet (0.61 acres) in size. Goal 2 – Improve habitat functions within Wetland A by reducing presence of invasive species and increasing presence of native vegetation and habitat features and diversity within the buffer areas Objective 2 – Effectively control and/or eliminate invasive species from the buffer restoration area. Performance Standard 2 – Non-native invasive plants will be removed from the restoration area. Objective 3 – Establish areas of differing forest and scrub-shrub communities and various habitats to create diverse horizontal and vertical vegetation structure and additional wildlife habitat. Performance Standard 3 – By the end of Year 5, the restoration area will have a least 3 species of native trees, 3 species of native shrubs, and 3 species of native vegetation; native volunteer species will be included in the count. 7.6 Plant Materials and Installation 7.6.1 Planting Plan The planting plan is approximate and subject to field verification prior to installation. All plantings are intended to establish a variety of native forested and scrub-shrub communities within the buffer. The proposed plant lists (Tables 6 through 8) and planting details are provided in Appendix C. The plant lists are based on a variety of factors such as habitat functions, availability of plant material, anticipated hydrology, and likelihood of survival and are intended to be adaptive under the direction of the Project Biologist. All areas will be planted with native shrubs and trees after seeding with the approved seed mixes to help prevent growth of invasive and noxious plants and after site stabilization and confirmation of site hydrology with the Project Biologist. In addition, a three-inch layer of mulch with a two-foot diameter will be placed around each tree or shrub to help maintain moisture around the plants and reduce competition from herbaceous species. Riparian and wetland seed mixes will be seeded throughout the restoration area. The intent of these mixes is to allow natural germination and adaption of herbaceous plants and prevent erosion. 7.6.2 Planting Materials All plant materials to be used on the site will be nursery grown stock from a reputable, local source. Only native species are to be used; no hybrids or cultivars will be allowed within the restoration area. Plant material provided will be typical of species or variety; if not bare root or cuttings, all plants will Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 19 exhibit normal, densely-developed branches and vigorous, fibrous root systems. Plants will be sound, healthy, vigorous plants free from defects, and all forms of disease and infestation. Container stock shall have been grown in its delivery container for not less than six months but not more than two years. Plants shall not exhibit root bound conditions. Seed mixture used for hand or hydroseeding shall contain fresh, clean, and new crop seed mixed by an approved method. The mixture is to be mixed to the specified proportions indicated in Table 6 by weight and tested to minimum percentages of purity and germination. Fertilizer will be in the form of Agroform plant tabs or an approved like form. Mulch will consist of sterile wheat straw or clean recycled wood chips approximately 1/2 inch to 1 inch in size and 1/2 inch thick. If free of invasive plant species, the mulch material may be sourced from woody materials salvaged from the land clearing activities. 7.6.3 Plant Scheduling, Species, Size, and Spacing Plant installation should occur as close to conclusion of clearing and grading activities as possible to limit erosion and limit the temporal loss of function provided by the buffer. All planting should occur between September 1 and May 1 to ensure plants do not dry out after installation, or temporary irrigation measures may be necessary. All planting will be installed according to the procedures detailed in the following subsections using the species and densities outlined in Tables 7 and 8 below. Table 6. Wetland Buffer and Wetland Seed Mix (substitutions allowed with Project Biologist approval) Species Name Common Name Plant Status Percentage by weight Meadow barley Hordeum brachyantherum FACW 50 Redtop Agrostis gigantea FAC 5 Spreading bluegrass Agrostis stolonifera FAC 5 Water foxtail Alopecurus geniculatus FACW 5 Slough sedge Carex obnupta OBL 5 Tufted hairgrass Deschampsia cespitosa FACW 5 Creeping spike rush Eleocharis palustris OBL 5 Reed managrass Glyceria grandis FACW 5 Slender rush Juncus tenuis FAC 5 Big trefoil Lotus pendunculatus FAC 5 Small tufted bulrush Scirpus microcarpus OBL 5 Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 20 Table 7. Tree Restoration Plan Plant Species Plant Name Spacing Size Scientific Common Plant Status Quantities Tree 32,577 SF Abies grandis Grand fir FACU 4 10 - 12 ft Bare root Acer macrophyllum Big leaf maple FACU 5 10 - 12 ft Bare root Alnus rubra Red Alder FAC 6 8 - 10 ft Bare root Betula papyrifera Paperbark birch FAC 18 8 - 10 ft Bare root Crataegus douglasii Douglas hawthorn FAC 6 4 - 5 ft Bare root Fraxinus latifolia Oregon ash FACW 3 8 - 10 ft Bare root Picea sitchensis Sitka spruce FAC 18 12 - 15 ft Bare root Pinus monticola Western white pine FACU 5 10 - 12 ft Bare Root Populus tremuloides Quaking aspen FACU 5 10 - 12 ft Bare root Populus trichocarpa Black cottonwood FAC 8 10 - 12 ft Bare root Prunus emarginata Bitter cherry FACU 18 10 - 12 ft Bare root Pseudotsuga menziesii Douglas fir FACU 18 10 - 12 ft Bare root Thuja plicata Western red cedar FAC 8 10 - 12 ft Bare root Tsuga heterophylla Western hemlock FACU 8 10 - 12 ft Bare root Table 8. Shrub Restoration Plan Plant Species Acer circinatum Vine maple FAC 40 4 - 5 ft Bare root Amelanchier alnifolia Service berry FACU 50 4 - 5 ft Bare root Cornus sericea Red-twig dogwood FACW 70 4 - 5 ft Bare root Corylus cornuta Western hazlenut FACU 40 4 - 5 ft Bare root Holodiscus discolor Oceanspray FACU 50 4 - 5 ft Bare root Lonicera involucrata Black twinberry FAC 50 4 - 5 ft Bare root Malus fusca Western crabapple FACW 24 8 - 10 ft Bare Root Oemleria cerasiformis Indian plum FACU 24 4 - 5 ft Bare root Physocarpus capitatus Pacific ninebark FACW 36 4 - 5 ft Bare root Rhamnus purshiana Cascara FAC 36 4 - 5 ft Bare root Ribes sanguineum Red-flowering currant (NL) UPL 40 4 - 5 ft Bare root Rosa nutkana Nootka rose FAC 40 4 - 5 ft Bare root Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 21 Rosa pisocarpa Clustered wild rose FAC 40 4 - 5 ft Bare root Rubus spectabilis Salmonberry FACU 36 4 - 5 ft Bare root Salix hookeriana Hooker's willow FACW 12 4 - 5 ft Stakes Salix lucida Pacific willow FACW 12 8 - 10 ft Stakes Salix scolleriana Scouler's willow FAC 12 4 - 5 ft Stakes Salix sitchensis Sitka willow FACW 12 4 - 5 ft Stakes Sambucus racemosa Red elderberry FACU 40 4 - 5 ft Bare root Symphoricarpos albus Snowberry FACU 40 4 - 5 ft Bare root 7.6.4 Quality Control for Planting Plan All plant material shall be inspected by the Project Biologist upon delivery. Plant material not conforming to the specifications above will be rejected and replaced by the planting contractor. Rejected plant materials shall be immediately removed from the site. Under no circumstances shall container stock be handled by their trunks, stems, or tops. The Landscape Contractor shall provide the Project Biologist with documentation of plant material that includes the supplying nursery contact information, plant species, plant quantities, and plant sizes. 7.6.5 Product Handling, Delivery, and Storage All seed and fertilizer should be delivered in original, unopened, and undamaged containers showing weight, analysis, and name of manufacturer. This material should be stored in a manner to prevent wetting and deterioration. All precautions customary in good trade practice shall be taken in preparing plants for moving. All plant materials to be used on the site will be nursery grown stock from a reputable, local source. Workmanship that fails to meet industry standards will be rejected. Plants will be packed, transported, and handled with care to ensure protection against injury and from drying out. If plants cannot be planted immediately upon delivery they should be protected with soil, wet peat moss, or in a manner acceptable to the project biologist. Plants, fertilizer, and mulch not installed immediately upon delivery shall be secured on the site to prevent theft or tampering. No plant shall be bound with rope or wire in a manner that could damage or break the branches. Plants transported on open vehicles should be secured with a protective covering to prevent windburn. Only native species are to be used; no hybrids or cultivars will be allowed. 7.6.6 Preparation and Installation of Plant Materials The Landscape Contractor shall verify the location of all elements of the restoration plan with the Project Biologist prior to installation. The responsible Project Biologist reserves the right to adjust the locations of landscape elements during the installation period as appropriate to the restoration actions outlined above. If obstructions are encountered that are not shown on the drawings, planting operations will cease until alternate plant locations have been selected by and/or approved by the Project Biologist. Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 22 Circular plant pits with vertical sides will be excavated for all container and bare root stock. The pits should be at least 12 inches in diameter, and the depth of the pit should accommodate the entire root system. The bottom of each pit will be scarified to a depth of 4 inches. Broken roots should be pruned with a sharp instrument and root-balls should be thoroughly soaked prior to installation. Set plant material upright in the planting pit to proper grade and alignment. Water plants thoroughly midway through backfilling and add Agroform tablets. Water pits again upon completion of backfilling. No filling should occur around trunks or stems. Do not use frozen or muddy mixtures for backfilling. Form a ring of soil around the edge of each planting pit to retain water, and install a 4 to 6 inch layer of mulch around the base of each container plant. 7.6.7 Temporary Irrigation Specifications While the native species selected for restoration are hardy and typically thrive in northwest conditions, and the proposed restoration actions are planned in areas with sufficient hydroperiods for the species selected, some individual plants might perish due to dry conditions. Therefore, a temporary irrigation system shall be installed to facilitate and help ensure watering will be provided for the duration of the first two growing seasons, as a minimum, while the native plantings become established. Temporary irrigation will be made available for a minimum of the first two growing seasons depending on plant vitality as determined by the Project Biologist. Weekly irrigation may be required between June 1 and October 30. The Landscape Contractor will be responsible for ensuring adequate irrigation is provided to help ensure plant survival. Unusual weather conditions (i.e. drought or lower than normal precipitation) may warrant extended irrigation for periods beyond those specified above. 7.6.8 Invasive Plant Control and Removal Invasive species to be removed include Himalayan blackberry and all listed noxious weeds. Non- native invasive plant species, specifically Himalayan blackerry are established within the on-site section of the buffer and require an effective control strategy. To ensure non-native invasive species do not expand following the restoration actions, non-native invasive plants within the entire restoration area will be pretreated with a root-killing herbicide approved for use in aquatic sites (i.e., Rodeo) a minimum of 2 weeks prior to being cleared and grubbed from the restoration area. A second application is strongly recommended. The pre-treatment with herbicide should occur prior to all planned restoration actions, and spot treatment of surviving non-native invasive vegetation should be performed again each fall prior to senescence for a minimum of 5 years. All Himalayan blackberry patches within the wetlands, ditches, or associated buffers on-site will be fully removed from the site. 7.7 Conceptual Maintenance & Voluntary Monitoring Plan Conceptual Maintenance and Voluntary Monitoring Plans are described below in accordance with RMC 4-3-050.L. The Applicant is committed to compliance with the restoration plan and overall success of the project. As such, the Applicant will continue to maintain the project, keeping the site free from of non-native invasive vegetation, trash, and yard waste. The wetland restoration actions will require continued voluntary monitoring and maintenance to ensure the actions are successful. Therefore, the buffer restoration area will be voluntarily monitored Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 23 for a period of 5 years with formal inspections by a qualified Wetland Scientist. Monitoring events will be scheduled at the time of construction, 30 days after planting, early in the growing season and the end of the growing season for Year 1, twice during Year 2, and annually in Years 3 and 5. Monitoring will consist of percent cover measurements at permanent monitoring stations, walk- through surveys to identify invasive species presence and dead or dying plantings, photographs taken at fixed photo points, wildlife observations, and general qualitative habitat and wetland function observations. To determine percent cover, observed vegetation will be identified and recorded by species and an estimate of areal cover of dominant species within each sampling plots. Circular sample plots, approximately 30 feet in diameter (706 square feet), are centered at each monitoring station. The sample plots encompass the specified wetland areas and terminate at the observed wetland boundary. Trees and shrubs within each 30-foot diameter monitoring plot are then recorded to species and areal cover. Herbaceous vegetation is sampled from a 10-foot diameter (78.5 square feet) within each monitoring plot, established at the same location as the center of each tree and shrub sample plot. Herbaceous vegetation within each monitoring plot is then recorded to species and includes an estimate of percent areal cover. A list of observed tree, shrub, and herbaceous species including percent areal cover of each species and wetland status is included within the monitoring report. 7.8 Voluntary Reporting Following each monitoring event, a brief voluntary monitoring report detailing the current ecological status of the mitigation actions, measurement of performance standards, and management recommendations will be prepared. 7.9 Contingency Plan If annual monitoring results indicate that the voluntary performance standards are not being met, it may be necessary to implement all or part of the contingency plan. Careful attention to maintenance is essential in ensuring that problems do not arise. Should any portion of the site fail to meet the success criteria, a contingency plan will be developed and implemented with regulatory approval. Such plans are adaptive and should be prepared on a case-by-case basis to reflect any failed restoration characteristics. Contingency plans can include additional grade control, plant installation, and/or plant substitutions including type, size, and location. Contingency/maintenance activities may include, but are not limited to: 1. Using plugs instead of seed for emergent vegetation coverage where seeded material does not become well-established; 2. Replacing plants lost to vandalism, drought, or disease, as necessary; 3. Replacing any plant species with a 20 percent or greater mortality rate after 2 growing seasons with the same species or native species of similar form and function; 4. Irrigating the restoration areas only as necessary during dry weather if plants appear to be too dry, with a minimal quantity of water; 5. Reseeding and/or repair of restoration areas as necessary if erosion or sedimentation occurs; 6. Spot treat non-native invasive plant species; 7. Removing all trash or undesirable debris from the wetland areas as necessary, and Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 24 8. Removing additional shrub species to ensure better light penetration to herbaceous groundcover. Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 25 Chapter 8. Closure The findings and conclusions documented in this report have been prepared for specific application to this project. They have been developed in a manner consistent with that level of care and skill normally exercised by members of the environmental science profession currently practicing under similar conditions in the area. Our work was also performed in accordance with the terms and conditions set forth in our proposal. The conclusions and recommendations presented in this report are professional opinions based on an interpretation of information currently available to us and are made within the operation scope, budget, and schedule of this project. No warranty, expressed or implied, is made. In addition, changes in government codes, regulations, or laws may occur. Due to such changes, our observations and conclusions applicable to this project may need to be revised wholly or in part. All wetland boundaries identified by Soundview Consultants LLC are based on conditions present at the time of the site inspection and considered preliminary until the flagged wetland boundaries are validated by the jurisdictional agencies. Validation of the wetland boundaries by the regulating agency provides a certification, usually written, that the wetland boundaries verified are the boundaries that will be regulated by the agencies until a specific date or until the regulations are modified. Only the regulating agencies can provide this certification. As wetlands are dynamic communities affected by both natural and human activities, changes in wetland boundaries may be expected; therefore, wetland delineations cannot remain valid for an indefinite period of time. Local agencies typically recognize the validity of wetland delineations for a period of five years after completion of a wetland delineation report. Development activities on a site five years after the completion of this wetland delineation report may require revision of the wetland delineation. In addition, changes in government codes, regulations, or laws may occur. Due of such changes, our observations and conclusions applicable to this site may need to be revised wholly or in part. Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 26 June 22, 2017 Chapter 9. Qualifications All field inspections, habitat assessments, and supporting documentation, including this Wetland and Fish and Wildlife Habitat Assessment Report prepared for Latitude Development were prepared by, or under the direction of Jeremy Downs and Jon Pickett of Soundview Consultants LLC with the assistance of Soundview Consultants LLC Wetland Scientist Emily Swaim and Staff Scientist, Melissa Cole. Jeremy Downs is an approved Wetlands Specialist and Environmental Planner and Jon Pickett is a project manager and environmental planner. Any deviations and/or alterations to this document must be approved by the aforementioned parties at Soundview Consultants LLC. Please see Appendix F for a description of professional qualifications. Jeremy Downs Date Senior Biologist/Environmental Planner Soundview Consultants LLC 2907 Harborview Drive Gig Harbor, Washington 98335 (253) 514-8952 Office (253) 514-8954 Fax jeremy@soundviewconsultants.com Jon Pickett Date Senior Scientist and Environmental Planner Soundview Consultants LLC 2907 Harborview Drive Gig Harbor, Washington 98335 (253) 514-8952 Office (253) 514-8954 Fax jon@soundviewconsultants.com June 22, 2017 Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 27 Chapter 10. References Brinson, M. M., 1993. “A Hydrogeomorphic Classification for Wetlands,” Technical Report WRP DE-4, U.S. Army Engineer Waterways Experiment Station, Vicksburg, MS. Cooke, S.S. 1997. Wetland Plants of Western Washington. Seattle Audubon Society. Seattle, Washington. Cowardin, L.M., V. Carter, F. Golet, and E.T. LaRoe. 1979. Classification of Wetlands and Deepwater Habitats of the United States. U.S. Fish & Wildlife Service. Washington D.C. Environmental Laboratory. 1987. Corps of Engineers Wetlands Delineation Manual. Technical Report Y- 87-1, US Army Engineer Waterways Experiment Station, Vicksburg, Mississippi. Federal Geographic Data Committee. 2013. Classification of Wetlands and Deepwater Habitats of the United States. FGDC-STD-004-2013. Second Edition. Wetlands Subcommittee, Federal Geographic Data Committee and U.S. Fish and Wildlife Service, Washington, DC. Granger, T., T. Hruby, A. McMillan, D. Peters, J. Rubey, D. Sheldon, S. Stanley, E. Stockdale. April 2005. Wetlands in Washington State - Volume 2: Guidance for Protecting and Managing Wetlands. Washington State Department of Ecology. Publication #05-06-008. Olympia, WA. Hruby, T. 2014. Washington State Wetland Rating System for Western Washington – Revised. Washington State Department of Ecology Publication # 14-06-029. King County iMap, 2017. Parcel Map and Topographic Map. Data accessed from website: http://gismaps.kingcounty.gov/iMap/?center=-13606090%2C6012570&scale=2256.994353&. Lichvar, R.W., D.L. Banks, W.N. Kirchner, and N.C. Melvin. 2016. The National Wetland Plant List: 2016 wetland ratings. Phytoneuron 2016-30: 1-17. Published 28 April 2016. ISSN 2153 733X Munsell Color. 2000. Munsell Soil Color Charts. New Windsor, New York. Natural Resources Conservation Service. 1995. Hydric Soils of Washington. U.S. Department of Agriculture. Washington D.C. Natural Resources Conservation Service. 2001. Hydric Soils List: King County, Washington. U.S. Department of Agriculture. Washington D.C. Natural Resources Conservation Service. 2016. The Plants Database. Data accessed from website: http://plants.usda.gov/java/. Natural Resources Conservation Service (NRCS), 2016. Soil Survey. Data accessed from website: https://websoilsurvey.sc.egov.usda.gov/App/WebSoilSurvey.aspx. Null, William, Skinner, Gloria, and Leonard, William. 2000. Wetland Functions Characterization Tool for Linear Projects. Washington State Department of Transportation. Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Page 28 Sheldon, D., T. Hruby, P. Johnson, K. Harper, A. McMillan, T. Granger, S. Stanley, and E. Stockdale. March 2005. Wetlands in Washington State - Volume 1: A Synthesis of the Science. Washington State Department of Ecology. Publication #05-06-006. Olympia, WA. Snyder, Dale E., Gale, Philip S., and Pringle, Russell F. 1973. Soil Survey of King County Area, Washington. Soil Conservation Service. U.S. Army Corps of Engineers. 2010. Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Western Mountains, Valleys, and Coast Region (Version 2.0), ed. J. S. Wakeley, R. W. Lichvar, and C. V. Noble. ERDC/EL TR-10-3. Vicksburg, MS: U.S. Army Engineer Research and Development. U.S. Fish and Wildlife Service. 2016. National Wetlands Inventory – V2. Data accessed from website: https://www.fws.gov/wetlands/Data/Mapper.html. Washington Department of Fish and Wildlife. 2008. Priority Habitat and Species List. Olympia, Washington. 177 pp. Washington Natural Heritage Program. Data published 07/24/15. Endangered, threatened, and sensitive plants of Washington. Washington State Department of Natural Resources, Washington Natural Heritage Program, Olympia, WA. Data accessed from website: http://www1.dnr.wa.gov/nhp/refdesk/datasearch/wnhpwetlands.pdf Washington State Department of Fish and Wildlife. 2017. Priority Habitats and Species. Data accessed from website: http://apps.wdfw.wa.gov/phsontheweb/. Washington State Department of Fish and Wildlife. 2016. SalmonScape. Data accessed from website: http://apps.wdfw.wa.gov/salmonscape/map.html. Washington State Department of Natural Resources (DNR), 2017. Forest Practices Application Mapping Tool Stream Typing. Data accessed from website: https://fortress.wa.gov/dnr/protectiongis/fpamt/. Washington State Legislator. 2016. Washington Administrative Code (WAC) 222-16-030. DNR Water typing system. Data accessed from website: http://apps.leg.wa.gov/wac/default.aspx?cite=222- 16-030. Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Appendix A — Methods and Tools Table A-1. Methods and tools used to prepare the report Parameter Method or Tool Website Reference Wetland Delineation USACE 1987 Wetland Delineation Manual USCAE 2010 WMVC Regional Supplement http://el.erdc.usace.army.mil/elpu bs/pdf/wlman87.pdf Environmental Laboratory. 1987. Corps of Engineers Wetlands Delineation Manual. Technical Report Y-87-1, US Army Engineer Waterways Experiment Station, Vicksburg, Mississippi. U.S. Army Corps of Engineers. 2010. Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Western Mountains, Valleys, and Coast Region (Version 2.0), ed. J. S. Wakeley, R. W. Lichvar, and C. V. Noble. ERDC/EL TR- 10-3. Vicksburg, MS: U.S. Army Engineer Research and Development. NWI https://www.fws.gov/wetlands/D ata/Mapper.html. U.S. Fish and Wildlife Service. 2016. National Wetlands Inventory – V2. Wetland Classification USFWS / Cowardin Classification System http://www.fws.gov/nwi/Pubs_R eports/Class_Manual/class_titlepg. htm Cowardin, L. M., V. Carter, F. C. Golet, E. T. LaRoe. 1979. Classification of wetlands and deepwater habitats of the United States. Government Printing Office, Washington, D.C. Federal Geographic Data Committee. 2013. Classification of wetlands and deepwater habitats of the United States. FGDC-STD-004-2013. Second Edition. Wetlands Subcommittee, Federal Geographic Data Committee and U.S. Fish and Wildlife Service, Washington, DC. Hydrogeomorphic Classification (HGM) System http://el.erdc.usace.army.mil/wetla nds/pdfs/wrpde4.pdf Brinson, M. M. (1993). “A Hydrogeomorphic Classification for Wetlands,” Technical Report WRP-DE-4, U.S. Army Engineer Waterways Experiment Station, Vicksburg, MS. Wetland Functions Characterization Tool for Linear Projects http://www.wsdot.wa.gov/nr/rdo nlyres/b92be0d4-9078-4efc-99da- 3c0ea4805e2f/0/bpjtool.pdf Null, William, Skinner, Gloria, and Leonard, William. 2000. Wetland Functions Characterization Tool for Linear Projects. Washington State Department of Transportation. Wetland Rating Washington State Wetland Rating System https://fortress.wa.gov/ecy/public ations/SummaryPages/1406029.ht ml Hruby. 2014. Washington State Wetland Rating System for Western Washington –Revised. Publication # 14-06-029. City of Renton Municipal Code, Wetlands http://www.codepublishing.com/ WA/Renton/ Renton Municipal Code 4-3-050. Drainage Classification Department of Natural Resources (DNR) Water Typing System Forest Practices Water Typing: http://www.stage.dnr.wa.gov/fore stpractices/watertyping/ WAC 222-16-030: http://apps.leg.wa.gov/WAC/defa ult.aspx?cite=222-16-030 Water Type Mapping: http://www3.wadnr.gov/dnrapp5/ website/fpars/viewer.htm Washington Administrative Code (WAC) 222-16-030. DNR Water typing system. City of Renton Stream Classification http://www.codepublishing.com/ WA/Renton/ Renton Municipal Code 4-3-050.G.2 Plants USDA Plant Database http://plants.usda.gov/ Website (see Appendix A) Wetland Plants of Western Washington http://soundnativeplants.com/wp- content/uploads/References_and_ Resources.pdf http://wetland- plants.usace.army.mil/nwpl_static/ Cooke, S.S. 1997. Wetland Plants of Western Washington. Seattle Audubon Society. Seattle, Washington. Lichvar, R.W., D.L. Banks, W.N. Kirchner, and N.C. Melvin. 2016. The National Wetland Plant List: 2016 wetland ratings. Phytoneuron 2016-30: 1-17. Published 28 April 2016. ISSN 2153 733X Soundview Consultants LLC June 22, 2017 1413.0004- East Valley Road- Wetland and Fish and Wildlife Habitat Assessment Parameter Method or Tool Website Reference 2016 Regional Wetland Plant List data/DOC/lists_2016/Regions/pd f/reg_WMVC_2016v1.pdf Soils Data NRCS Soil Survey http://websoilsurvey.nrcs.usda.gov /app/WebSoilSurvey.aspx Snyder, Dale E., Gale, Philip S., and Pringle, Russell F. 1973. Soil Survey of King County Area, Washington. Soil Conservation Service. Soil Color Charts Munsell Color. 2000. Munsell Soil Color Charts. New Windsor, New York. Hydric Soils Data King County Hydric Soils List http://www.wa.nrcs.usda.gov/tech nical/soils/hydric_lists/hydsoil-wa- 653.pdf Natural Resources Conservation Service. 1995. Hydric Soils of Washington. U.S. Department of Agriculture. Washington D.C. Natural Resources Conservation Service. 2001. Hydric Soils List: King County, Washington. U.S. Department of Agriculture. Washington D.C. Threatened and Endangered Species Washington Natural Heritage Program http://www1.dnr.wa.gov/nhp/ref desk/datasearch/wnhpwetlands.pd f Washington Natural Heritage Program (Data published 07/24/15). Endangered, threatened, and sensitive plants of Washington. Washington State Department of Natural Resources, Washington Natural Heritage Program, Olympia, WA Washington Priority Habitats and Species http://wdfw.wa.gov/hab/phspage. htm Priority Habitats and Species (PHS) Program (Data requested 02/01/17). Map of priority habitats and species in project vicinity. Washington Department of Fish and Wildlife. Washington SalmonScape http://apps.wdfw.wa.gov/salmons cape/map.html SalmonScape (Data requested on 11/30/16). Washington State Department of Fish and Wildlife. NOAA fisheries species list and maps http://www.nwr.noaa.gov/ESA- Salmon-Listings/Salmon- Populations/Index.cfm and http://www.nmfs.noaa.gov/pr/sp ecies/ Website Species of Local Importance WDFW GIS Data http://wdfw.wa.gov/mapping/sal monscape/ and http://apps.wdfw.wa.gov/phsonth eweb/. Website Report Preparation King County iMap. http://gismaps.kingcounty.gov/iM ap/ Interactive Mapping Tool Renton Municipal Code http://www.codepublishing.com/ WA/Renton/ Website Soundview Consultants LLC June 22, 2017 1413.0004- East Valley Road- Wetland and Fish and Wildlife Habitat Assessment Appendix B – Background Information This Appendix includes a King County Parcel Map (B1), Historical Aerial Photographs (B2), King County Hydrography and Topographic Map (B3), Renton Wetlands, Streams, and Flood Zones Map (B4), USFWS NWI map (B5), NRCS Soil Survey map (B6), DNR Stream Typing map (B7), WDFW SalmonScape map (B8), WDFW PHS map (B9) and Prior Accepted Wetland Rating and Application (B10). Soundview Consultants LLC June 22, 2017 1413.0001 – East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Appendix B1. King County Parcel Map Subject Property (Approximate) Soundview Consultants LLC June 22, 2017 1413.0004 – East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Appendix B2. Historical Aerials King County 1936 Aerial Photograph Subject Property (Approximate) Soundview Consultants LLC June 22, 2017 1413.0004 – East Valley Road - Wetland and Fish and Wildlife Habitat Assessment HistoricalAerials.com 1940 Aerial Photograph Subject Property (Approximate) Soundview Consultants LLC June 22, 2017 1413.0004 – East Valley Road - Wetland and Fish and Wildlife Habitat Assessment HistoricalAerials.com 1964 Aerial Photograph Subject Property (Approximate) Soundview Consultants LLC June 22, 2017 1413.0004 – East Valley Road - Wetland and Fish and Wildlife Habitat Assessment King County 1998 Aerial Photograph Subject Property (Approximate) Soundview Consultants LLC June 22, 2017 1413.0004 – East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Appendix B3. King County Hydrography and Topographic Map Subject Property (Approximate) Soundview Consultants LLC June 22, 2017 1413.0004 – East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Appendix B4. Renton Wetlands, Streams, and Flood Zones Map Subject Property (Approximate) Soundview Consultants LLC June 22, 2017 1413.0004 – East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Appendix B5. USFWS NWI Map Subject Property (Approximate) Soundview Consultants LLC June 22, 2017 1413.0004 – East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Appendix B6. NRCS Soil Survey Map Subject Property (Approximate) Soundview Consultants LLC June 22, 2017 1413.0004 – East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Appendix B7. DNR Stream Typing Map Subject Property (Approximate) Soundview Consultants LLC June 22, 2017 1413.0004 – East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Appendix B8. WDFW SalmonScape Map Subject Property (Approximate) Soundview Consultants LLC June 22, 2017 1413.0004 – East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Appendix B9. WDFW PHS Map Subject Property (Approximate) Soundview Consultants LLC June 22, 2017 1413.0004 – East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Soundview Consultants LLC June 22, 2017 1413.0004 – East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Appendix B10. Prior Accepted Wetland Rating and Application Permit Details https://permitsearch.mybuildingpermit.com/...ails.aspx?permitnumber=PRE16-000978&permitstatus=Complete&parcelnumber=302305-9103[6/22/2017 1:34:30 PM] Permit Details Activities Inspections Conditions Fees INFORMATION ON PERMIT PRE16-000978 Permit Status: Complete (status definition)Description: People Data: (click for applicant/owner/contractor details)2,372 sq. ft. expansion of the north end of the existing building located at 2500 East Valley Road. Expansion would add two fully enclosed truck bays. Site Address: 2500 East Valley Rd Application Date: Dec 30, 2016 Parcel Number: 302305-9103 (property map & information) City Staff: Angelea Weihs Activities Plan Added City Staff: Alex Morganroth Status: Applied Date: Dec 30, 2016 Notes: PLAN Added Inspections Conditions Fees Item Fee Amount Fee Remaining Other permits associated with this parcel Permit Number Status Description LUA17-000324 In Review The applicant is requesting Environmental Review, an Urban Design Modification, a Street Modification, and a Minor Modification to an approved Site Plan for a proposed 2,673 square foot addition to the existing 28,065 square foot building located at 2500 E Valley Rd (Parcel number 3023059103). The subject site is 3.07 acres (134,074 sf) and is zoned Commercial Arterial (CA). The building is currently used as administrative offices for US Bank. The expansion would enlarge the building’s footprint from 28,065 square feet to 30,738 square feet. Existing access is gained via East Valley Road. The proposed development would include two enclosed truck bays, removal of parking stalls, and a new landscape planter strips along the sides of the building expansion. Seismic hazards are mapped on the project site. A Category III wetland is mapped off-site within 50 feet of the property. The applicant has requested and received an administrative determination that the project is exempt from the required wetland buffer setbacks, due to the existing separation from the wetland by pre-existing, intervening, and lawfully created substantial existing improvements, per RMC 4-3-050B.1.g. B17002305 Plan Check/In Review REMODEL OF EXISTING OFFICE SPACE FOR US BANK. 12,780 SQ FT PRE16-000978 Complete 2,372 sq. ft. expansion of the north end of the existing building located at 2500 East Valley Road. Expansion would add two fully enclosed truck bays. E16005396 Finaled A (Nonresidential Alteration) project installing (Temporary Service). Additional Info (). Work Site Location () E16005035 Issued A (Nonresidential Alteration) project installing (Temporary Service). Additional Info (). Work Site Location () E15007386 Expired A (Nonresidential Alteration) project installing (Security system). Additional Info (). Work Site Location () Close this window Permit Details https://permitsearch.mybuildingpermit.com/...ails.aspx?permitnumber=PRE16-000978&permitstatus=Complete&parcelnumber=302305-9103[6/22/2017 1:34:30 PM] E15007203 Finaled ELEC- LOAD BANK TEST 250 KW GENERATOR FOR US BANK E15002857 Finaled A (Nonresidential Addition) project installing (Security system; Door Locks). Additional Info (). Work Site Location () E14004966 Finaled A (Nonresidential Alteration) project installing (Panel). Additional Info (). Work Site Location () E14002643 Finaled US BANK - LOW VOLTAGE - INSTALL CABLE SUPPORT ABOVE CEILING E14001094 Finaled A (Nonresidential Alteration) project installing (Data cable system). Additional Info (). Work Site Location () E13004903 Finaled US BANK - LOADBANK GENERATOR TEST F13003885 Finaled REPLACE SCAN UNIT WITH AES RADIO E13003755 Expired A (Multifamily Residential Alteration) project installing (Fire Alarms). Additional Info (NE Corner Phone Room). Work Site Location (Building C) E111220 Finaled INSTALL 300 KW GENERATOR FOR US BANK DATA CENTER-OTC PER AS E110898 Finaled US BANK-INSTALL 1 LS-15R RECEPTACLE IN DEMARC RM E110703 Finaled INSTALL 4 IN CONDUIT AND DS-3 COAX FOR US BANK E110276 Finaled INSTALL LOW VOLT. VOICE & DATA CABLE AT US BANK T.I. E110222 Finaled INSTALL POWER MODIFICATIONS TO BRANCH CIRCUITS AT US BANK - SUITE C B110044 Finaled CONSTRUCT INTERIOR T.I. FOR US BANK E101525 Finaled MOVE OUTLET FOR MONITOR AT RENTON DATA CENTER E101527 Finaled INSTALL CIRCUITS FOR U S BANK P09-052 Recorded 3 LOT SHORT PLAT WITH EXISTING BUILDINGS LUA09-042 Recorded The applicant is proposing to subdivide an existing parcel into 3 lots which contains an existing three building office development to be retained. The proposed lots would range in size from 10,335 square feet up to 27,723 square feet; each of the lots would contain one of the three existing commercial buildings. The subject property is located on the east side of East Valley Road just north of SW 27th Street. The project site totals 5.59 acres in area and is zoned Commercial Arterial (CA). Access for the proposed lots would be provided via existing driveways along East Valley Road. An addendum to the existing SEPA Determination of Non- Significance-Mitigated, issued for the construction of the office development (ECF- 053-87), is also being requested in order to recognize the proposed lot lines. 5/19/09 - Appeal and reconsideration received. 7/1/09 - Planning Director responded to reconsideration upholding the approval of the plat with a revision to condition 2 of the initial report & decision dated 5/5/09. New appeal period ends 7/15/09. 7/15/09 - Appeal of Planning Director's reconsideration decision received. Appeal scheduled to be heard by the Hearing Examiner on 7/28/09. 7/28/09 - Hearing Examiner opened and continued heaing to a date TBD. 8/13/10 - Stipulation & Order agreement removing condition #1 of the Administrative Report & Decision dated 5/5/09 was signed by the applicant, City Attorney, & Hearing Examiner - appeal withdrawn. PRE08-030 Complete 3 LOT SHORT PLAT WITH THREE EXISTING COMMERCIAL BUILDINGS. 4/1/08 - APPLICANT REQUESTED THE LANDSCAPING IMPROVEMENTS BE WAIVED AS PART OF THE SHORT PLAT. NEIL WATTS DETERMINED THAT THE LANDSCOING WOULD NOT BE WAIVED. 4/3/08- APPLICANT REQUESTED A WETLAND STUDY, PROVIDED BY DOT FOR A HWY 167 PROJECT, TAKE THE PLACE OF THE STREAM STUDY REQUIRED FOR PROJECT REVIEW. NEIL WATTS DETERMINED THAT A STREAM STUDY DONE FOR THE SITE IS NECCESSARY AND THE STUDY DONE BY DOT WOULD NOT SATISFY THIS REQUIREMENT. E071243 Finaled INSTALL WIRING TO REPLACE HVAC UNITS AT US BANK M070370 Finaled REPLACEMENT OF EQUIPMENT (3 UNITS) AT US BANK P06-214 Expired CONVERT COMMERCIAL BLDG TO CHURCH USE LUA06-130 Expired The applicant is requesting a Hearing Examiner Conditional Use Permit to operate the Oasis Seattle Church on a 244,807 square foot (5.6 acre) site located within the Commercial Arterial (CA) zoning designation and the Employment Area Valley (EAV) Overlay. The Oasis Seattle Church has approximately 400 members. Services are held on Thursdays from 6-9 pm and on Sunday from 8 am-2 pm. Parking would be Permit Details https://permitsearch.mybuildingpermit.com/...ails.aspx?permitnumber=PRE16-000978&permitstatus=Complete&parcelnumber=302305-9103[6/22/2017 1:34:30 PM] provided within the existing parking lot located on the project site. No building or landscaping improvments are proposed at this time. PRE06-071 Complete PREAPP MEETING TO DISCUSS THE FEASIBILITY OF A CONDITIONAL USE PERMIT FOR A CHURCH IN THE CA ZONE. F050109 Finaled INSTALL FIRE ALARM SYSTEM F040248 Finaled FIRE PANEL REPLACEMENT E040985 Finaled INSTALL (1) NEW PROGRAMMABLE THERMOSTAT/U.S. BANK M040314 Finaled INSTALL ROOF TOP HEAT PUMP AT US BANK E040712 Finaled ADD NEW LTG PANEL, RELOCATE LTG BRANCH CKTS, NEW UPS FEEDER/U.S. BANK SUITE C E020045 Finaled INSTALL VIDEO CABLE TO PROJECTOR-MANUFACTURE INDUSTRIAL OFFICE B000634 Finaled ADD NEW OFFICE FOR FAA WITHIN EXISTING BUILDING E001305 Finaled INSTALL ELECT.FOR TENANT IMPROVEMENT/FAA E000231 Finaled INSTALL LOW VOLTAGE SECURITY SYSTEM/#C2 B980437 Expired TI FOR US BANCORP/EXPIRED TOSSED PLANS E980867 Finaled CONNECT ELECTRIC TO HVAC EQUIPMENT B980352 Finaled CONSTRUCT STRUCTURAL MODIFICATIONS FOR MECH. M980266 Finaled 1 ROOFTOP GAS A/C UNIT 150,000 BTU/2 RELIEF SYST./2 GAS PIPE.REV.FOR US BANK.ALTER.3EXIST.SYST.8/3 E980816 Finaled ADD 1 LOW VOLT.T-STAT FOR US BANK E980738 Finaled INSTALL LOW VOLTAGE DATA CABELING - SUITE C E980732 Finaled ADD TELE POWER POLES & MISC CLEAN UP OF CIRCUITS B980257 Finaled REMOVE PARTITION WALLS S970080 Finaled INSTALL RAISED LETTER SIGN FOR AEROTEK E971237 Finaled INSTALL VOICE & DATA CABLE FOR FAA TI P970422 Finaled INSTALL PLUMBING FOR FAA TI F970208 Finaled INSTALLATION OF FIRE SPRINKLERS E971195 Finaled INSTALL LIGHTING & POWER FOR FAA TI M970536 Finaled INSTALL 1 3 TON A/C UNIT/2 5 TON AC UNITS & 5 EXH.FANS FOR FAA TI. E971193 Finaled INSTALL 3 24 VOLT THERMOSTATS FOR FAA TI B970512 Finaled CONSTRUCT OFFICE TENANT IMPROVEMENT FOR FAA E970280 Finaled INSTALL TELEPHONE WIRING FOR AEROTEC TI E970215 Finaled WIRE 9 POWER INTERIOR POWER POLES IN AEROTEC TI F970024 Finaled INSTALLATION OF FIRE SPRINKLERS E970078 Finaled INSTALL ELECTRICAL IN AEROTEC TI BLG.#C P970026 Finaled INSTALL PLUMBING IN AREOTECH TI BLDG.#C M970022 Finaled INSTALL 3 HEAT PUMPS(3 TON)/4 EXHAUST FANS (100 CFM)/1 HEAT PUMP (7 1/2 TON) E970054 Finaled INSTALL 4 THERMOSTATS E970034 Finaled INSTALL SERVICE AND FEEDER B960830 Finaled AEROTEC TENANT IMPROVEMENT FOR BLDG C E961125 Finaled ADD 2 CIRCUIT FOR ACCESS CONTROL #7-84 E961126 Finaled INSTALL 2 DOOR ACCESS CONTROL SYSTEM (LOW VOLT.) #7-84 E960979 Finaled INSTALL LOW VOLTAGE CONTROL OF HVAC FOR U.S.BANK F960153 Finaled RELOCATE 5 HEADS, PLUG 2 E960949 Finaled RELOCATE ALARM IN US BANK OF WASHINGTON E960900 Finaled INSTALL LOW VOLTAGE DATA CABLING FOR U.S.BANK M960423 Finaled RELOCATE EXISTING DIFFUSERS & R.A.G.S FOR RENTON DATA CTR. E960875 Finaled NSTALL ELECTRICAL TO WIRE OFFICES FOR US BANK TI B960470 Finaled INTERIOR DEMOLITION FOR U.S.BANK TI B960468 Finaled U.S.BANK TENANT IMPROVEMENT F940193 Finaled INSTALL SPRINKLERS FOR TI (#B940313) Soundview Consultants LLC June 22, 2017 1413.0004 East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Appendix C – Site Plans T EAST VALLEY ROADEAST VALLEY ROADPROPERTY BOUNDARY56' REDUCEDWETLAND BUFFER15' BUILDING SETBACKVVVVVVVVVVDITCH Z(UNREGULATED)141 LF ON-SITE75' STANDARDWETLAND BUFFER56'E A S T V A L L E Y R O A DWETLAND ACATEGORY III(8,333 SF ON-SITE)OFF-SITEWETLAND AAPPROX. 25,874 SF(NOT DELINEATED)STORMWATERPONDS R - 1 6 7DITCH Z(UNREGULATED) 145 LF OFF-SITEPROPERTY BOUNDARYOFF-SITEWETLAND AAPPROX.BOUNDARY(NOT DELINEATED)EAST VALLEY ROAD - EXISTING CONDITIONS 1SCALE: SEE GRAPHICSOURCES: EAST VALLEY ROAD 2960 EAST VALLEY ROAD RENTON, WASHINGTON 98057 THE NE 1 4 OF SECTION 30, TOWNSHIP 23N, RANGE 05E, W.M.DATE: 3/22/2017BY: DSJOB: 1413.0004SHEET OF 32215 North 30th Street, Suite 300 Tacoma, WA 98403 253.383.2422 TEL 253.383.2572 FAX www.ahbl.com WEB TACOMA SEATTLE SPOKANE TRI-CITIES PRELIMINARYINFORMATION ONLYNOT FOR CONSTRUCTIONSOUNDVIEW CONSULTANTS, LLC. ASSUMESNO LIABILITY OR RESPONSIBILITY FORCONSTRUCTION, IMPROVEMENTS, ORESTIMATES BASED ON THIS PLAN SETDRAFT FOR REVIEW T EAST VALLEY ROADEAST VALLEY ROADPROPERTY BOUNDARY56' REDUCEDWETLAND BUFFER15' BUILDING SETBACKVVVVVVVVVVDITCH Z(UNREGULATED)141 LF ON-SITE75' STANDARDWETLAND BUFFER56'NO IMPROVEMENTSIN THIS PARCELWETLAND APROPOSED BUFFERRESTORATION AREA(32,577 SF)PROPOSED LUMBERDISTRIBUTION ANDRETAIL FACILITYPROPOSEDHUMMOCK WITHEXISTING TREESPROTECTEXISTING TREETO REMAIN (TYP.)LARGE WOODYDEBRIS (TYP.)HUMMOCKS TO PRESERVEEXISTING TREES TOREMAIN56' REDUCEDWETLAND BUFFERNOTE:SEE SHEET 4 FOR DETAILS, PLANT SCHEDULE ANDADDITIONAL PLANTING INFORMATION,E A S T V A L L E Y R O A DWETLAND ACATEGORY III(8,333 SF ON-SITE)OFF-SITEWETLAND AAPPROX. 25,874 SF(NOT DELINEATED)STORMWATERPONDDITCH Z(UNREGULATED) 145 LF OFF-SITEPROPERTY BOUNDARYEAST VALLEY ROAD - PROPOSED PROJECT 2SCALE: SEE GRAPHICSOURCES: EAST VALLEY ROAD 2960 EAST VALLEY ROAD RENTON, WASHINGTON 98057 THE NE 1 4 OF SECTION 30, TOWNSHIP 23N, RANGE 05E, W.M.DATE: 3/22/2017BY: DSJOB: 1413.0004SHEET OF 32215 North 30th Street, Suite 300 Tacoma, WA 98403 253.383.2422 TEL 253.383.2572 FAX www.ahbl.com WEB TACOMA SEATTLE SPOKANE TRI-CITIES PRELIMINARYINFORMATION ONLYNOT FOR CONSTRUCTIONSOUNDVIEW CONSULTANTS, LLC. ASSUMESNO LIABILITY OR RESPONSIBILITY FORCONSTRUCTION, IMPROVEMENTS, ORESTIMATES BASED ON THIS PLAN SETDRAFT FOR REVIEW EAST VALLEY ROAD - PLANT DETAILS 3SCALE: SEE GRAPHICSOURCES: EAST VALLEY ROAD 2960 EAST VALLEY ROAD RENTON, WASHINGTON 98057 THE NE 1 4 OF SECTION 30, TOWNSHIP 23N, RANGE 05E, W.M.DATE: 3/22/2017BY: DSJOB: 1413.0004SHEET OF 32215 North 30th Street, Suite 300 Tacoma, WA 98403 253.383.2422 TEL 253.383.2572 FAX www.ahbl.com WEB TACOMA SEATTLE SPOKANE TRI-CITIES SCALE: 1" = 20' - 0"WETLAND BUFFER RESTORATION SAMPLE PLANTING PLANPLANT SCHEDULENOTES:1 - PROTECT EXISTING TREES TO REMAIN.2 - PLANT TREES AND SHRUBS IN GROUPINGS OF 3 TO 11 PLANTS.3 - ALTHOUGH PLANTS MAY BE STAKED OR LAID OUT IN REGULAR TRIANGULAR SPACING PRIOR TOPLANTING, ADJUST PLANT LAYOUT AND GROUPINGS BEFORE PLANTING TO AVOID STRAIGHT LINESAND TO PROVIDE NATURAL-LOOKING PLANT COMMUNITIES.PROPOSED HUMMOCK WITH EXISTINGAND PROPOSED TREES AND SHRUBS56' REDUCEDWETLAND BUFFERLARGEWOODYDEBRISSTREAM BUFFER SEED MIXTHROUGHOUT BUFFERPROPERTY BOUNDARYWETLAND ANOT TO SCALEHUMMOCK DETAIL (TYPICAL)HUMMOCKNOTES:1. PLANT SHRUBS OF THE SAMESPECIES IN GROUPS OF 3 to 6 ASAPPROPRIATE.2. EXCAVATE PIT TO FULL DEPTH OFROOT MASS AND CANOPYDIAMETER. SPREAD ROOTS TOFULL WIDTH OF CANOPY.3. MIDWAY THROUGH PLANTING ADDAGROFORM TABLET AND WATERTHOROUGHLY.4. BACKFILL TO BE COMPACTEDUSING WATER ONLY.5. WATER IMMEDIATELY AFTERINSTALLATION.LOCATOR LATH (IF SPECIFIED)3 to 4 INCH LAYER OF MULCHNOT TO SCALETREE & SHRUB PLANTING DETAIL (TYPICAL)PRELIMINARYINFORMATION ONLYNOT FOR CONSTRUCTIONSOUNDVIEW CONSULTANTS, LLC. ASSUMESNO LIABILITY OR RESPONSIBILITY FORCONSTRUCTION, IMPROVEMENTS, ORESTIMATES BASED ON THIS PLAN SETDRAFT FOR REVIEW EAST VALLEY ROAD - SITE DETAILS 4SCALE: SEE GRAPHICSOURCES: EAST VALLEY ROAD 2960 EAST VALLEY ROAD RENTON, WASHINGTON 98057 THE NE 1 4 OF SECTION 30, TOWNSHIP 23N, RANGE 05E, W.M.DATE: 3/22/2017BY: DSJOB: 1413.0004SHEET OF 32215 North 30th Street, Suite 300 Tacoma, WA 98403 253.383.2422 TEL 253.383.2572 FAX www.ahbl.com WEB TACOMA SEATTLE SPOKANE TRI-CITIESNOT TO SCALEHUMMOCK DETAIL (TYPICAL)HUMMOCKNOTES:1. PLANT SHRUBS OF THE SAMESPECIES IN GROUPS OF 3 to 6 ASAPPROPRIATE.2. EXCAVATE PIT TO FULL DEPTH OFROOT MASS AND CANOPYDIAMETER. SPREAD ROOTS TOFULL WIDTH OF CANOPY.3. MIDWAY THROUGH PLANTING ADDAGROFORM TABLET AND WATERTHOROUGHLY.4. BACKFILL TO BE COMPACTEDUSING WATER ONLY.5. WATER IMMEDIATELY AFTERINSTALLATION.LOCATOR LATH (IF SPECIFIED)3 to 4 INCH LAYER OF MULCHNOT TO SCALETREE & SHRUB PLANTING DETAIL (TYPICAL)NOT TO SCALEANCHOR LARGE WOODY DEBRIS WITHDUCK-BILL ANCHOR WITH GALVANIZED CABLEOR APPROVED EQUIVALENT TO BEDETERMINED BY PROJECT ENGINEER.LARGE WOODY DEBRIS DETAILAT STREAM BANK (TYPICAL)BANKFULL WIDTHDRAFT FOR REVIEW Soundview Consultants LLC June 22, 2017 1413.0004 – East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Appendix D – Data Forms US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 WETLAND DETERMINATION DATA FORM – Western Mountains, Valleys, and Coast Region Project/Site: 1413.0004 East Valley Road City/County: Renton/King Sampling Date:12-15-2016 Applicant/Owner: Latitude Development- Donovan Brothers State: WA Sampling Point: DP-1 Investigator(s): J. Pickett and E. Swaim Section, Township, Range: T23N, R5E, Section 30 Landform (hillslope, terrace, etc.): slope Local relief (concave, convex, none): Concave Slope (%): 3 Subregion (LRR): A2 Lat: 47.45495 Long: -122.21672 Datum: WGS 84 Soil Map Unit Name: Urban Land / Tukwila Muck (inaccurately mapped) NWI classification: N/A Are climatic / hydrologic conditions on the site typical for this time of year? Yes No (If no, explain in Remarks.) Are Vegetation x, Soil x, or Hydrology x significantly disturbed? Are “Normal Circumstances” present? Yes No Are Vegetation , Soil , or Hydrology naturally problematic? (If needed, explain any answers in Remarks.) SUMMARY OF FINDINGS – Attach site map showing sampling point locations, transects, important features, etc. Hydrophytic Vegetation Present? Yes No Hydric Soil Present? Yes No Wetland Hydrology Present? Yes No Is the Sampled Area within a Wetland? Yes No Remarks: All three wetland criteria observed. Area highly developed and heavily disturbed from adjacent land uses. Precipitation 144 percent of normal for the water year to the date of the site visit. VEGETATION – Use scientific names of plants. Absolute Dominant Indicator Tree Stratum (Plot size: 30 ft) % Cover Species? Status 1. Salix lucida 50 Y FACW 2. Alnus rubra 30 Y FAC 3. 4. 80 = Total Cover Sapling/Shrub Stratum (Plot size: 15 ft) 1. Rubus armeniacus 25 Y FAC 2. Cornus alba 5 N FACW 3. 4. 5. 30 = Total Cover Herb Stratum (Plot size: 5 ft) 1. Polystichum munitum 1 Y FACU 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 1 = Total Cover Woody Vine Stratum (Plot size: 30 ft) 1. 2. = Total Cover % Bare Ground in Herb Stratum 99 Dominance Test worksheet: Number of Dominant Species That Are OBL, FACW, or FAC: 3 (A) Total Number of Dominant Species Across All Strata: 4 (B) Percent of Dominant Species That Are OBL, FACW, or FAC: 75 (A/B) Prevalence Index worksheet: Total % Cover of: Multiply by: OBL species x 1 = FACW species x 2 = FAC species x 3 = FACU species x 4 = UPL species x 5 = Column Totals: (A) (B) Prevalence Index = B/A = Hydrophytic Vegetation Indicators: Rapid Test for Hydrophytic Vegetation Dominance Test is >50% Prevalence Index is ≤3.01 Morphological Adaptations1 (Provide supporting data in Remarks or on a separate sheet) Wetland Non-Vascular Plants1 Problematic Hydrophytic Vegetation1 (Explain) 1Indicators of hydric soil and wetland hydrology must be present, unless disturbed or problematic. Hydrophytic Vegetation Present? Yes No Remarks: Hydrophytic vegetation criteria observed. Bare ground observed due to permanent ponding. US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 SOIL Sampling Point: DP-1 Profile Description: (Describe to the depth needed to document the indicator or confirm the absence of indicators.) Depth Matrix Redox Features (inches) Color (moist) % Color (moist) % Type1 Loc2 Texture Remarks 0-5 2.5Y 2.5/1 100 - - - - GSL/FILL Fill/Gravel 1Type: C=Concentration, D=Depletion, RM=Reduced Matrix, CS=Covered or Coated Sand Grains. 2Location: PL=Pore Lining, M=Matrix. Hydric Soil Indicators: (Applicable to all LRRs, unless otherwise noted.) Indicators for Problematic Hydric Soils3: Histosol (A1) Sandy Redox (S5) 2 cm Muck (A10) Histic Epipedon (A2) Stripped Matrix (S6) Red Parent Material (TF2) Black Histic (A3) Loamy Mucky Mineral (F1) (except MLRA 1) Very Shallow Dark Surface (TF12) Hydrogen Sulfide (A4) Loamy Gleyed Matrix (F2) Other (Explain in Remarks) Depleted Below Dark Surface (A11) Depleted Matrix (F3) Thick Dark Surface (A12) Redox Dark Surface (F6) 3Indicators of hydrophytic vegetation and Sandy Mucky Mineral (S1) Depleted Dark Surface (F7) wetland hydrology must be present, Sandy Gleyed Matrix (S4) Redox Depressions (F8) unless disturbed or problematic. Restrictive Layer (if present): Type:________________________________ Depth (inches):________________________ Hydric Soil Present? Yes No Remarks: Hydric soil indicator A4 observed- Hydrogen sulfide aroma. HYDROLOGY Wetland Hydrology Indicators: Primary Indicators (minimum of one required; check all that apply) Secondary Indicators (2 or more required) Surface Water (A1) Water-Stained Leaves (B9) (except MLRA Water-Stained Leaves (B9) (MLRA 1, 2, High Water Table (A2) 1, 2, 4A, and 4B) 4A, and 4B) Saturation (A3) Salt Crust (B11) Drainage Patterns (B10) Water Marks (B1) Aquatic Invertebrates (B13) Dry-Season Water Table (C2) Sediment Deposits (B2) Hydrogen Sulfide Odor (C1) Saturation Visible on Aerial Imagery (C9) Drift Deposits (B3) Oxidized Rhizospheres along Living Roots (C3) Geomorphic Position (D2) Algal Mat or Crust (B4) Presence of Reduced Iron (C4) Shallow Aquitard (D3) Iron Deposits (B5) Recent Iron Reduction in Tilled Soils (C6) FAC-Neutral Test (D5) Surface Soil Cracks (B6) Stunted or Stressed Plants (D1) (LRR A) Raised Ant Mounds (D6) (LRR A) Inundation Visible on Aerial Imagery (B7) Other (Explain in Remarks) Frost-Heave Hummocks (D7) Sparsely Vegetated Concave Surface (B8) Field Observations: Surface Water Present? Yes No Depth (inches): +12 Water Table Present? Yes No Depth (inches): surface Saturation Present? Yes No Depth (inches): surface (includes capillary fringe) Wetland Hydrology Present? Yes No Describe Recorded Data (stream gauge, monitoring well, aerial photos, previous inspections), if available: 144 percent of normal for the water year to the date of the site vist (10/01/2016-12/15/16). Remarks: Primary hydrologic indicators A1-A3 and C1 observed as well as secondary hydrologic indicators B9, B10, D2, and D5. GRAVEL / FILL 5 inches below ground surface US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 WETLAND DETERMINATION DATA FORM – Western Mountains, Valleys, and Coast Region Project/Site: 1413.0004 East Valley Road City/County: Renton/King Sampling Date:12-15-2016 Applicant/Owner: Latitude Development- Donovan Brothers State: WA Sampling Point: DP-2 Investigator(s): J. Pickett and E. Swaim Section, Township, Range: T23N, R5E, Section 30 Landform (hillslope, terrace, etc.): Developed terrace Local relief (concave, convex, none): None Slope (%): 0 Subregion (LRR): A2 Lat: 47.454741 Long: -122.216764 Datum: WGS 84 Soil Map Unit Name: Urban Land NWI classification: N/A Are climatic / hydrologic conditions on the site typical for this time of year? Yes No (If no, explain in Remarks.) Are Vegetation x, Soil x, or Hydrology significantly disturbed? Are “Normal Circumstances” present? Yes No Are Vegetation , Soil , or Hydrology naturally problematic? (If needed, explain any answers in Remarks.) SUMMARY OF FINDINGS – Attach site map showing sampling point locations, transects, important features, etc. Hydrophytic Vegetation Present? Yes No Hydric Soil Present? Yes No Wetland Hydrology Present? Yes No Is the Sampled Area within a Wetland? Yes No Remarks: No wetland criteria observed in the developed location of DP-2. Area highly developed and heavily disturbed from adjacent land uses. Precipitation 144 percent of normal for the water year to the date of the site visit. Disturbance noted due to development. VEGETATION – Use scientific names of plants. Absolute Dominant Indicator Tree Stratum (Plot size: 30 ft) % Cover Species? Status 1. 2. 3. 4. = Total Cover Sapling/Shrub Stratum (Plot size: 15 ft) 1. 2. 3. 4. 5. = Total Cover Herb Stratum (Plot size: 5 ft) 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. = Total Cover Woody Vine Stratum (Plot size: 30 ft) 1. 2. = Total Cover % Bare Ground in Herb Stratum 0 Dominance Test worksheet: Number of Dominant Species That Are OBL, FACW, or FAC: (A) Total Number of Dominant Species Across All Strata: (B) Percent of Dominant Species That Are OBL, FACW, or FAC: (A/B) Prevalence Index worksheet: Total % Cover of: Multiply by: OBL species x 1 = FACW species x 2 = FAC species x 3 = FACU species x 4 = UPL species x 5 = Column Totals: (A) (B) Prevalence Index = B/A = Hydrophytic Vegetation Indicators: Rapid Test for Hydrophytic Vegetation Dominance Test is >50% Prevalence Index is ≤3.01 Morphological Adaptations1 (Provide supporting data in Remarks or on a separate sheet) Wetland Non-Vascular Plants1 Problematic Hydrophytic Vegetation1 (Explain) 1Indicators of hydric soil and wetland hydrology must be present, unless disturbed or problematic. Hydrophytic Vegetation Present? Yes No Remarks: No vegetation located in area of data plot. Located in area of gravel fill development. US Army Corps of Engineers Western Mountains, Valleys, and Coast – Version 2.0 SOIL Sampling Point: DP-2 Profile Description: (Describe to the depth needed to document the indicator or confirm the absence of indicators.) Depth Matrix Redox Features (inches) Color (moist) % Color (moist) % Type1 Loc2 Texture Remarks - - - - - - - GSL/FILL Fill/Gravel 1Type: C=Concentration, D=Depletion, RM=Reduced Matrix, CS=Covered or Coated Sand Grains. 2Location: PL=Pore Lining, M=Matrix. Hydric Soil Indicators: (Applicable to all LRRs, unless otherwise noted.) Indicators for Problematic Hydric Soils3: Histosol (A1) Sandy Redox (S5) 2 cm Muck (A10) Histic Epipedon (A2) Stripped Matrix (S6) Red Parent Material (TF2) Black Histic (A3) Loamy Mucky Mineral (F1) (except MLRA 1) Very Shallow Dark Surface (TF12) Hydrogen Sulfide (A4) Loamy Gleyed Matrix (F2) Other (Explain in Remarks) Depleted Below Dark Surface (A11) Depleted Matrix (F3) Thick Dark Surface (A12) Redox Dark Surface (F6) 3Indicators of hydrophytic vegetation and Sandy Mucky Mineral (S1) Depleted Dark Surface (F7) wetland hydrology must be present, Sandy Gleyed Matrix (S4) Redox Depressions (F8) unless disturbed or problematic. Restrictive Layer (if present): Type:________________________________ Depth (inches):________________________ Hydric Soil Present? Yes No Remarks: No hydric soil indicators observed. Fill and gravel are not actual soil textures. Hard and compacted gravel fill. Not applicable to soil testing. HYDROLOGY Wetland Hydrology Indicators: Primary Indicators (minimum of one required; check all that apply) Secondary Indicators (2 or more required) Surface Water (A1) Water-Stained Leaves (B9) (except MLRA Water-Stained Leaves (B9) (MLRA 1, 2, High Water Table (A2) 1, 2, 4A, and 4B) 4A, and 4B) Saturation (A3) Salt Crust (B11) Drainage Patterns (B10) Water Marks (B1) Aquatic Invertebrates (B13) Dry-Season Water Table (C2) Sediment Deposits (B2) Hydrogen Sulfide Odor (C1) Saturation Visible on Aerial Imagery (C9) Drift Deposits (B3) Oxidized Rhizospheres along Living Roots (C3) Geomorphic Position (D2) Algal Mat or Crust (B4) Presence of Reduced Iron (C4) Shallow Aquitard (D3) Iron Deposits (B5) Recent Iron Reduction in Tilled Soils (C6) FAC-Neutral Test (D5) Surface Soil Cracks (B6) Stunted or Stressed Plants (D1) (LRR A) Raised Ant Mounds (D6) (LRR A) Inundation Visible on Aerial Imagery (B7) Other (Explain in Remarks) Frost-Heave Hummocks (D7) Sparsely Vegetated Concave Surface (B8) Field Observations: Surface Water Present? Yes No Depth (inches): Water Table Present? Yes No Depth (inches): Saturation Present? Yes No Depth (inches): (includes capillary fringe) Wetland Hydrology Present? Yes No Describe Recorded Data (stream gauge, monitoring well, aerial photos, previous inspections), if available: 144 percent of normal for the water year to the date of the site vist (10/01/2016-12/15/16) according to the SeaTac Airport NOAA data. Remarks: No primary nor secondary indicators of wetland hydrology observed. Soundview Consultants LLC June 22, 2017 1413.0004 – East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Appendix E – Wetland Rating Form Wetland name or number A Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 1 WSDOT Adapted Form - March 2, 2015 Name of wetland (or ID #):Date of site visit:12/15/2016 Rated by Trained by Ecology? Yes No Date of training 3/31/2016 HGM Class used for rating Wetland has multiple HGM classes? Yes No NOTE: Form is not complete with out the figures requested (figures can be combined ). Source of base aerial photo/map OVERALL WETLAND CATEGORY III (based on functions or special characteristics ) 1. Category of wetland based on FUNCTIONS Category I - Total score = 23 - 27 Score for each Category II - Total score = 20 - 22 function based X Category III - Total score = 16 - 19 on three Category IV - Total score = 9 - 15 ratings (order of ratings is not important ) L M 9 = H, H, H H L 8 = H, H, M M L Total 7 = H, H, L 7 = H, M, M 6 = H, M, L 6 = M, M, M 5 = H, L, L 5 = M, M, L 4 = M, L, L 3 = L, L, L 2. Category based on SPECIAL CHARACTERISTICS of wetland XNone of the above Coastal Lagoon Interdunal Value Score Based on Ratings 6 6 4 16 H CHARACTERISTIC Category Estuarine Wetland of High Conservation Value Bog Mature Forest Old Growth Forest Depressional & Flats RATING SUMMARY – Western Washington List appropriate rating (H, M, L) HydrologicImproving Water Quality LSite Potential Landscape Potential Habitat M FUNCTION Wetland A 1413.0004 J. Downs and E.Swaim Google Earth 2016 Wetland name or number A Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 2 WSDOT Adapted Form - March 2, 2015 Wetland name or number A Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 3 WSDOT Adapted Form - March 2, 2015 Maps and Figures required to answer questions correctly for Western Washington Depressional Wetlands Map of: Figure # Cowardin plant classes Hydroperiods Location of outlet (can be added to map of hydroperiods ) Boundary of area within 150 ft of the wetland (can be added to another figure ) Map of the contributing basin 1 km Polygon: Area that extends 1 km from entire wetland edge - including polygons for accessible habitat and undisturbed habitat Screen capture of map of 303(d) listed waters in basin (from Ecology website) Screen capture of list of TMDLs for WRIA in which unit is found (from web) Riverine Wetlands Map of: Figure # Cowardin plant classes Hydroperiods Ponded depressions Boundary of area within 150 ft of the wetland (can be added to another figure ) Plant cover of trees, shrubs, and herbaceous plants Width of unit vs. width of stream (can be added to another figure ) Map of the contributing basin 1 km Polygon: Area that extends 1 km from entire wetland edge - including polygons for accessible habitat and undisturbed habitat Screen capture of map of 303(d) listed waters in basin (from Ecology website) Screen capture of list of TMDLs for WRIA in which unit is found (from web) Lake Fringe Wetlands Map of: Figure # Cowardin plant classes Plant cover of trees, shrubs, and herbaceous plants Boundary of area within 150 ft of the wetland (can be added to another figure ) 1 km Polygon: Area that extends 1 km from entire wetland edge - including polygons for accessible habitat and undisturbed habitat Screen capture of map of 303(d) listed waters in basin (from Ecology website) Screen capture of list of TMDLs for WRIA in which unit is found (from web) Slope Wetlands Map of: Figure # Cowardin plant classes Hydroperiods Plant cover of dense trees, shrubs, and herbaceous plants Plant cover of dense, rigid trees, shrubs, and herbaceous plants (can be added to another figure ) Boundary of area within 150 ft of the wetland (can be added to another figure ) 1 km Polygon: Area that extends 1 km from entire wetland edge - including polygons for accessible habitat and undisturbed habitat To answer questions: D 1.3, H 1.1, H 1.4 D 1.4, H 1.2 D 1.1, D 4.1 D 2.2, D 5.2 D 4.3, D 5.3 H 2.1, H 2.2, H 2.3 D 3.1, D 3.2 D 3.3 To answer questions: H 1.1, H 1.4 H 1.2 R 1.1 R 2.4 R 1.2, R 4.2 R 4.1 R 2.2, R 2.3, R 5.2 H 2.1, H 2.2, H 2.3 L 1.2 L 2.2 L 3.1, L 3.2 L 3.3 H 2.1, H 2.2, H 2.3 R 3.1 R 3.2, R 3.3 To answer questions: L 1.1, L 4.1, H 1.1, H 1.4 S 4.1 S 2.1, S 5.1 To answer questions: H 1.1, H 1.4 H 1.2 S 1.3 H 2.1, H 2.2, H 2.3 Wetland name or number A Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 4 WSDOT Adapted Form - March 2, 2015 Screen capture of map of 303(d) listed waters in basin (from Ecology website) Screen capture of list of TMDLs for WRIA in which unit is found (from web) S 3.1, S 3.2 S 3.3 Wetland name or number A Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 5 WSDOT Adapted Form - March 2, 2015 For questions 1 -7, the criteria described must apply to the entire unit being rated. 1. Are the water levels in the entire unit usually controlled by tides except during floods? NO - go to 2 YES - the wetland class is Tidal Fringe - go to 1.1 1.1 Is the salinity of the water during periods of annual low flow below 0.5 ppt (parts per thousand)? NO - Saltwater Tidal Fringe (Estuarine)YES - Freshwater Tidal Fringe NO - go to 3 YES - The wetland class is Flats If your wetland can be classified as a Flats wetland, use the form for Depressional wetlands. 3. Does the entire wetland unit meet all of the following criteria? NO - go to 4 YES - The wetland class is Lake Fringe (Lacustrine Fringe) 4. Does the entire wetland unit meet all of the following criteria? The wetland is on a slope (slope can be very gradual ), The water leaves the wetland without being impounded. NO - go to 5 YES - The wetland class is Slope 5. Does the entire wetland unit meet all of the following criteria? The overbank flooding occurs at least once every 2 years. NO - go to 6 YES - The wetland class is Riverine NOTE: The Riverine unit can contain depressions that are filled with water when the river is not flooding. If hydrologic criteria listed in each question do not apply to the entire unit being rated, you probably have a unit with multiple HGM classes. In this case, identify which hydrologic criteria in questions 1 - 7 apply, and go to Question 8. At least 30% of the open water area is deeper than 6.6 ft (2 m). HGM Classification of Wetland in Western Washington If your wetland can be classified as a Freshwater Tidal Fringe use the forms for Riverine wetlands. If it is Saltwater Tidal Fringe it is an Estuarine wetland and is not scored. This method cannot be used to score functions for estuarine wetlands. The vegetated part of the wetland is on the shores of a body of permanent open water (without any plants on the surface at any time of the year) at least 20 ac (8 ha) in size; The water flows through the wetland in one direction (unidirectional) and usually comes from seeps. It may flow subsurface, as sheetflow, or in a swale without distinct banks. NOTE: Surface water does not pond in these type of wetlands except occasionally in very small and shallow depressions or behind hummocks (depressions are usually <3 ft diameter and less than 1 ft deep). The unit is in a valley, or stream channel, where it gets inundated by overbank flooding from that stream or river, 2. The entire wetland unit is flat and precipitation is the only source (>90%) of water to it. Groundwater and surface water runoff are NOT sources of water to the unit. Wetland name or number A Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 6 WSDOT Adapted Form - March 2, 2015 NO - go to 7 YES - The wetland class is Depressional NO - go to 8 YES - The wetland class is Depressional NOTES and FIELD OBSERVATIONS: 7. Is the entire wetland unit located in a very flat area with no obvious depression and no overbank flooding? The unit does not pond surface water more than a few inches. The unit seems to be maintained by high groundwater in the area. The wetland may be ditched, but has no obvious natural outlet. 8. Your wetland unit seems to be difficult to classify and probably contains several different HGM classes. For example, seeps at the base of a slope may grade into a riverine floodplain, or a small stream within a Depressional wetland has a zone of flooding along its sides. GO BACK AND IDENTIFY WHICH OF THE HYDROLOGIC REGIMES DESCRIBED IN QUESTIONS 1-7 APPLY TO DIFFERENT AREAS IN THE UNIT (make a rough sketch to help you decide). Use the following table to identify the appropriate class to use for the rating system if you have several HGM classes present within the wetland unit being scored. 6. Is the entire wetland unit in a topographic depression in which water ponds, or is saturated to the surface, at some time during the year? This means that any outlet, if present, is higher than the interior of the wetland. Riverine Treat as ESTUARINE Slope + Lake Fringe Depressional + Riverine along stream within boundary of depression Depressional + Lake Fringe Riverine + Lake Fringe NOTE: Use this table only if the class that is recommended in the second column represents 10% or more of the total area of the wetland unit being rated. If the area of the HGM class listed in column 2 is less than 10% of the unit; classify the wetland using the class that represents more than 90% of the total area. HGM classes within the wetland unit being rated Slope + Riverine Slope + Depressional Depressional Depressional If you are still unable to determine which of the above criteria apply to your wetland, or if you have more than 2 HGM classes within a wetland boundary, classify the wetland as Depressional for the rating. Salt Water Tidal Fringe and any other class of freshwater wetland HGM class to use in rating Riverine Depressional Lake Fringe Wetland name or number A Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 8 WSDOT Adapted Form - March 2, 2015 D 1.1. Characteristics of surface water outflows from the wetland: points = 3 points = 2 points = 1 points = 1 Yes = 4 No = 0 Wetland has persistent, ungrazed, plants > 95% of area points = 5 Wetland has persistent, ungrazed, plants > ½ of area points = 3 Wetland has persistent, ungrazed plants > 1/10 of area points = 1 Wetland has persistent, ungrazed plants < 1/10 of area points = 0 D 1.4. Characteristics of seasonal ponding or inundation: This is the area that is ponded for at least 2 months. See description in manual. Area seasonally ponded is > ½ total area of wetland points = 4 Area seasonally ponded is > ¼ total area of wetland points = 2 Area seasonally ponded is < ¼ total area of wetland points = 0 Total for D 1 Add the points in the boxes above 4 Rating of Site Potential If score is: 12 - 16 = H 6 - 11 = M 0 - 5 = L Record the rating on the first page D 2.1. Does the wetland unit receive stormwater discharges?Yes = 1 No = 0 1 Yes = 1 No = 0 D 2.3. Are there septic systems within 250 ft of the wetland?Yes = 1 No = 0 0 Source Yes = 1 No = 0 Total for D 2 Add the points in the boxes above 2 Rating of Landscape Potential If score is: 3 or 4 = H 1 or 2 = M 0 = L Record the rating on the first page Yes = 1 No = 0 Yes = 1 No = 0 Yes = 2 No = 0 Total for D 3 Add the points in the boxes above 3 Rating of Value If score is: 2 - 4 = H 1 = M 0 = L Record the rating on the first page D 3.3. Has the site been identified in a watershed or local plan as important for maintaining water quality (answer YES if there is a TMDL for the basin in which the unit is found )? D 1.2. The soil 2 in below the surface (or duff layer) is true clay or true organic (use NRCS definitions ). D 1.3. Characteristics and distribution of persistent plants (Emergent, Scrub-shrub, and/or Forested Cowardin classes): D 2.4. Are there other sources of pollutants coming into the wetland that are not listed in questions D 2.1 - D 2.3? D 3.1. Does the wetland discharge directly (i.e., within 1 mi) to a stream, river, lake, or marine water that is on the 303(d) list? D 2.2. Is > 10% of the area within 150 ft of the wetland in land uses that generate pollutants? D 3.2. Is the wetland in a basin or sub-basin where an aquatic resource is on the 303(d) list? D 3.0. Is the water quality improvement provided by the site valuable to society? 1 0 2 0 3 DEPRESSIONAL AND FLATS WETLANDS 1 0 Water Quality Functions - Indicators that the site functions to improve water quality D 1.0. Does the site have the potential to improve water quality? 1 Wetland has an unconstricted, or slightly constricted, surface outlet that is permanently flowing Wetland has an intermittently flowing stream or ditch, OR highly constricted permanently flowing outlet. Wetland is a depression or flat depression (QUESTION 7 on key) with no surface water leaving it (no outlet). Wetland is a flat depression (QUESTION 7 on key), whose outlet is a permanently flowing ditch. 0 D 2.0. Does the landscape have the potential to support the water quality function of the site? Wetland name or number A Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 10 WSDOT Adapted Form - March 2, 2015 D 4.1. Characteristics of surface water outflows from the wetland: points = 4 points = 2 points = 1 points = 0 Marks of ponding are 3 ft or more above the surface or bottom of outlet points = 7 Marks of ponding between 2 ft to < 3 ft from surface or bottom of outlet points = 5 Marks are at least 0.5 ft to < 2 ft from surface or bottom of outlet points = 3 The wetland is a “headwater” wetland points = 3 Wetland is flat but has small depressions on the surface that trap water points = 1 Marks of ponding less than 0.5 ft (6 in)points = 0 The area of the basin is less than 10 times the area of the unit points = 5 The area of the basin is 10 to 100 times the area of the unit points = 3 The area of the basin is more than 100 times the area of the unit points = 0 Entire wetland is in the Flats class points = 5 Total for D 4 Add the points in the boxes above 3 Rating of Site Potential If score is: 12 - 16 = H 6 - 11 = M 0 - 5 = L Record the rating on the first page D 5.1. Does the wetland unit receive stormwater discharges?Yes = 1 No = 0 1 D 5.2. Is > 10% of the area within 150 ft of the wetland in land uses that generate excess runoff? Yes = 1 No = 0 Yes = 1 No = 0 Total for D 5 Add the points in the boxes above 3 Rating of Landscape Potential If score is: 3 = H 1 or 2 = M 0 = L Record the rating on the first page points = 2 points = 1 Flooding from groundwater is an issue in the sub-basin.points = 1 points = 0 1 1 D 5.3. Is more than 25% of the contributing basin of the wetland covered with intensive human land uses (residential at >1 residence/ac, urban, commercial, agriculture, etc.)? The existing or potential outflow from the wetland is so constrained by human or natural conditions that the water stored by the wetland cannot reach areas that flood. Explain why 1 3 D 4.2. Depth of storage during wet periods: Estimate the height of ponding above the bottom of the outlet. For wetlands with no outlet, measure from the surface of permanent water or if dry, the deepest part. D 4.3. Contribution of the wetland to storage in the watershed: Estimate the ratio of the area of upstream basin contributing surface water to the wetland to the area of the wetland unit itself. D 6.1. The unit is in a landscape that has flooding problems. Choose the description that best matches conditions around the wetland unit being rated. Do not add points. Choose the highest score if more than one condition is met. Hydrologic Functions - Indicators that the site functions to reduce flooding and stream degradation D 4.0. Does the site have the potential to reduce flooding and erosion? 0 Wetland is a depression or flat depression with no surface water leaving it (no outlet) Wetland has an unconstricted, or slightly constricted, surface outlet that is permanently flowing Wetland has an intermittently flowing stream or ditch, OR highly constricted permanently flowing outlet Wetland is a flat depression (QUESTION 7 on key), whose outlet is a permanently flowing ditch 0 D 5.0. Does the landscape have the potential to support hydrologic function of the site? D 6.0. Are the hydrologic functions provided by the site valuable to society? The wetland captures surface water that would otherwise flow down-gradient into areas where flooding has damaged human or natural resources (e.g., houses or salmon redds): Flooding occurs in a sub-basin that is immediately down- gradient of unit. Surface flooding problems are in a sub-basin farther down- gradient. DEPRESSIONAL AND FLATS WETLANDS Wetland name or number A Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 11 WSDOT Adapted Form - March 2, 2015 There are no problems with flooding downstream of the wetland.points = 0 Yes = 2 No = 0 Total for D 6 Add the points in the boxes above 1 Rating of Value If score is: 2 - 4 = H 1 = M 0 = L Record the rating on the first page D 6.2. Has the site been identified as important for flood storage or flood conveyance in a regional flood control plan? Wetland name or number A Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 12 WSDOT Adapted Form - March 2, 2015 HABITAT FUNCTIONS - Indicators that site functions to provide important habitat H 1.0. Does the site have the potential to provide habitat? Aquatic bed 4 structures or more: points = 4 Emergent 3 structures: points = 2 Scrub-shrub (areas where shrubs have > 30% cover)2 structures: points - 1 Forested (areas where trees have > 30% cover)1 structure: points = 0 If the unit has a Forested class, check if : H 1.2. Hydroperiods Permanently flooded or inundated 4 or more types present: points = 3 Seasonally flooded or inundated 3 types present: points = 2 Occasionally flooded or inundated 2 types present: points = 1 Saturated only 1 types present: points = 0 Permanently flowing stream or river in, or adjacent to, the wetland Seasonally flowing stream in, or adjacent to, the wetland Lake Fringe wetland 2 points Freshwater tidal wetland 2 points H 1.3. Richness of plant species If you counted:> 19 species points = 2 5 - 19 species points = 1 < 5 species points = 0 H 1.4. Interspersion of habitats None = 0 points Low = 1 point Moderate = 2 points All three diagrams in this row are 1 Check the types of water regimes (hydroperiods) present within the wetland. The water regime has to cover more than 10% of the wetland or ¼ ac to count (see text for descriptions of hydroperiods ). 1 Count the number of plant species in the wetland that cover at least 10 ft2.Different patches of the same species can be combined to meet the size threshold and you do not have to name the species. Do not include Eurasian milfoil, reed canarygrass, purple loosestrife, Canadian thistle 1 Decide from the diagrams below whether interspersion among Cowardin plants classes (described in H 1.1), or the classes and unvegetated areas (can include open water or mudflats) is high, moderate, low, or none. If you have four or more plant classes or three classes and open water, the rating is always high. These questions apply to wetlands of all HGM classes. The Forested class has 3 out of 5 strata (canopy, sub-canopy, shrubs, herbaceous, moss/ground-cover) that each cover 20% within the Forested polygon 1 H 1.1. Structure of plant community: Indicators are Cowardin classes and strata within the Forested class. Check the Cowardin plant classes in the wetland. Up to 10 patches may be combined for each class to meet the threshold of ¼ ac or more than 10% of the unit if it is smaller than 2.5 ac. Add the number of structures checked. Wetland name or number A Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 13 WSDOT Adapted Form - March 2, 2015 HIGH = 3 points Wetland name or number A Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 14 WSDOT Adapted Form - March 2, 2015 H 1.5. Special habitat features: Large, downed, woody debris within the wetland (> 4 in diameter and 6 ft long) Standing snags (dbh > 4 in) within the wetland Total for H 1 Add the points in the boxes above 7 Rating of Site Potential If Score is: 15 - 18 = H 7 - 14 = M 0 - 6 = L Record the rating on the first page H 2.0. Does the landscape have the potential to support the habitat function of the site? H 2.1 Accessible habitat (include only habitat that directly abuts wetland unit ). Calculate: 0 % undisturbed habitat + (0.29 % moderate & low intensity land uses / 2 ) = 0.145% If total accessible habitat is: > 1/3 (33.3%) of 1 km Polygon points = 3 20 - 33% of 1 km Polygon points = 2 10 - 19% of 1 km Polygon points = 1 < 10 % of 1 km Polygon points = 0 H 2.2. Undisturbed habitat in 1 km Polygon around the wetland. Calculate: 5 % undisturbed habitat + (2.3 % moderate & low intensity land uses / 2 ) = 6.15% Undisturbed habitat > 50% of Polygon points = 3 Undisturbed habitat 10 - 50% and in 1-3 patches points = 2 Undisturbed habitat 10 - 50% and > 3 patches points = 1 Undisturbed habitat < 10% of 1 km Polygon points = 0 H 2.3 Land use intensity in 1 km Polygon: If > 50% of 1 km Polygon is high intensity land use points = (-2) ≤ 50% of 1km Polygon is high intensity points = 0 Total for H 2 Add the points in the boxes above -2 Rating of Landscape Potential If Score is: 4 - 6 = H 1 - 3 = M < 1 = L Record the rating on the first page Site meets ANY of the following criteria:points = 2 It has 3 or more priority habitats within 100 m (see next page) It is mapped as a location for an individual WDFW priority species Check the habitat features that are present in the wetland. The number of checks is the number of points. It has been categorized as an important habitat site in a local or regional comprehensive plan, in a Shoreline Master Plan, or in a Undercut banks are present for at least 6.6 ft (2 m) and/or overhanging plants extends at least 3.3 ft (1 m) over a stream (or ditch) in, or contiguous with the wetland, for at least 33 ft (10 m) Stable steep banks of fine material that might be used by beaver or muskrat for denning (> 30 degree slope) OR signs of recent beaver activity are present (cut shrubs or trees that have not yet weathered where wood is exposed ) At least ¼ ac of thin-stemmed persistent plants or woody branches are present in areas that are permanently or seasonally inundated (structures for egg-laying by amphibians ) 3 It is a Wetland of High Conservation Value as determined by the Department of Natural Resources 0 Invasive plants cover less than 25% of the wetland area in every stratum of plants (see H 1.1 for list of strata ) 0 0 -2 H 3.0. Is the habitat provided by the site valuable to society? H 3.1. Does the site provide habitat for species valued in laws, regulations, or policies? Choose only the highest score that applies to the wetland being rated . It provides habitat for Threatened or Endangered species (any plant or animal on the state or federal lists) Wetland name or number A Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 15 WSDOT Adapted Form - March 2, 2015 Site has 1 or 2 priority habitats (listed on next page) with in 100m points = 1 Site does not meet any of the criteria above points = 0 Rating of Value If Score is: 2 = H 1 = M 0 = L Record the rating on the first page watershed plan Wetland name or number A Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 16 WSDOT Adapted Form - March 2, 2015 Aspen Stands: Pure or mixed stands of aspen greater than 1 ac (0.4 ha). Herbaceous Balds: Variable size patches of grass and forbs on shallow soils over bedrock. Cliffs: Greater than 25 ft (7.6 m) high and occurring below 5000 ft elevation. Priority habitats listed by WDFW (see complete descriptions of WDFW priority habitats, and the counties in which they can be found, in: Washington Department of Fish and Wildlife. 2008. Priority Habitat and Species List. Olympia, Washington. 177 pp. Oregon White Oak: Woodland stands of pure oak or oak/conifer associations where canopy coverage of the oak component is important (full descriptions in WDFW PHS report p. 158 – see web link above ). Riparian: The area adjacent to aquatic systems with flowing water that contains elements of both aquatic and terrestrial ecosystems which mutually influence each other. Westside Prairies: Herbaceous, non-forested plant communities that can either take the form of a dry prairie or a wet prairie (full descriptions in WDFW PHS report p. 161 – see web link above ). Instream: The combination of physical, biological, and chemical processes and conditions that interact to provide functional life history requirements for instream fish and wildlife resources. Nearshore: Relatively undisturbed nearshore habitats. These include Coastal Nearshore, Open Coast Nearshore, and Puget Sound Nearshore. (full descriptions of habitats and the definition of relatively undisturbed are in WDFW report – see web link on previous page ). Snags and Logs: Trees are considered snags if they are dead or dying and exhibit sufficient decay characteristics to enable cavity excavation/use by wildlife. Priority snags have a diameter at breast height of > 20 in (51 cm) in western Washington and are > 6.5 ft (2 m) in height. Priority logs are > Talus: Homogenous areas of rock rubble ranging in average size 0.5 - 6.5 ft (0.15 - 2.0 m), composed of basalt, andesite, and/or sedimentary rock, including riprap slides and mine tailings. May be associated with cliffs. Caves: A naturally occurring cavity, recess, void, or system of interconnected passages under the earth in soils, rock, ice, or other geological formations and is large enough to contain a human. WDFW Priority Habitats Count how many of the following priority habitats are within 330 ft (100 m) of the wetland unit: NOTE : This question is independent of the land use between the wetland unit and the priority habitat. Biodiversity Areas and Corridors: Areas of habitat that are relatively important to various species of native fish and wildlife (full descriptions in WDFW PHS report ). Old-growth/Mature forests: Old-growth west of Cascade crest – Stands of at least 2 tree species, forming a multi-layered canopy with occasional small openings; with at least 8 trees/ac (20 trees/ha) > 32 in (81 cm) dbh or > 200 years of age. Mature forests – Stands with average diameters exceeding 21 in (53 cm) dbh; crown cover may be less than 100%; decay, decadence, numbers of snags, and quantity of large downed material is generally less than that found in old-growth; 80-200 years old west of the Cascade crest. http://wdfw.wa.gov/publications/00165/wdfw00165.pdf or access the list from here: http://wdfw.wa.gov/conservation/phs/list/ Wetland name or number A Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 17 WSDOT Adapted Form - March 2, 2015 12 in (30 cm) in diameter at the largest end, and > 20 ft (6 m) long. Note: All vegetated wetlands are by definition a priority habitat but are not included in this list because they are addressed elsewhere. Wetland name or number A Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 18 WSDOT Adapted Form - March 2, 2015 Wetland Type Category Check off any criteria that apply to the wetland. List the category when the appropriate criteria are met. SC 1.0. Estuarine Wetlands Does the wetland meet the following criteria for Estuarine wetlands? The dominant water regime is tidal, Vegetated, and With a salinity greater than 0.5 ppt Yes - Go to SC 1.1 No = Not an estuarine wetland SC 1.1. Yes = Category I No - Go to SC 1.2 SC 1.2.Is the wetland unit at least 1 ac in size and meets at least two of the following three conditions? Yes = Category I No = Category II SC 2.0. Wetlands of High Conservation Value (WHCV) SC 2.1. Yes - Go to SC 2.2 No - Go to SC 2.3 SC 2.2.Is the wetland listed on the WDNR database as a Wetland of High Conservation Value? Yes = Category I No = Not WHCV SC 2.3.Is the wetland in a Section/Township/Range that contains a Natural Heritage wetland? http://www1.dnr.wa.gov/nhp/refdesk/datasearch/wnhpwetlands.pdf Yes - Contact WNHP/WDNR and to SC 2.4 No = Not WHCV SC 2.4. Yes = Category I No = Not WHCV SC 3.0. Bogs SC 3.1. Yes - Go to SC 3.3 No - Go to SC 3.2 SC 3.2. Yes - Go to SC 3.3 No = Is not a bog SC 3.3. Yes = Is a Category I bog No - Go to SC 3.4 SC 3.4. NOTE: If you are uncertain about the extent of mosses in the understory, you may substitute that criterion by measuring the pH of the water that seeps into a hole dug at least 16 in deep. If the pH is less than 5.0 and the plant species in Table 4 are present, the wetland is a bog. Is an area with peats or mucks forested (> 30% cover) with Sitka spruce, subalpine fir, CATEGORIZATION BASED ON SPECIAL CHARACTERISTICS Is the wetland within a National Wildlife Refuge, National Park, National Estuary Reserve, Natural Area Preserve, State Park or Educational, Environmental, or Scientific Reserve designated under WAC 332-30-151? The wetland is relatively undisturbed (has no diking, ditching, filling, cultivation, grazing, and has less than 10% cover of non-native plant species. (If non-native species are Spartina , see page 25) At least ¾ of the landward edge of the wetland has a 100 ft buffer of shrub, forest, or un- grazed or un-mowed grassland. The wetland has at least two of the following features: tidal channels, depressions with open water, or contiguous freshwater wetlands. Has WDNR identified the wetland within the S/T/R as a Wetland of High Conservation Value and listed it on their website? Has the WA Department of Natural Resources updated their website to include the list of Wetlands of High Conservation Value? Does the wetland (or any part of the unit) meet both the criteria for soils and vegetation in bogs? Use the key below. If you answer YES you will still need to rate the wetland based on its functions . Does an area within the wetland unit have organic soil horizons, either peats or mucks, that compose 16 in or more of the first 32 in of the soil profile? Does an area within the wetland unit have organic soils, either peats or mucks, that are less than 16 in deep over bedrock, or an impermeable hardpan such as clay or volcanic ash, or that are floating on top of a lake or pond? Does an area with peats or mucks have more than 70% cover of mosses at ground level, AND at least a 30% cover of plant species listed in Table 4? Wetland name or number A Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 19 WSDOT Adapted Form - March 2, 2015 Yes = Is a Category I bog No = Is not a bog p ( ) p , p , western red cedar, western hemlock, lodgepole pine, quaking aspen, Engelmann spruce, or western white pine, AND any of the species (or combination of species) listed in Table 4 provide more than 30% of the cover under the canopy? Wetland name or number A Wetland Rating System for Western WA: 2014 Update Rating Form - Effective January 1, 2015 20 WSDOT Adapted Form - March 2, 2015 SC 4.0. Forested Wetlands Yes = Category I No = Not a forested wetland for this section SC 5.0. Wetlands in Coastal Lagoons Does the wetland meet all of the following criteria of a wetland in a coastal lagoon? Yes - Go to SC 5.1 No = Not a wetland in a coastal lagoon SC 5.1. Does the wetland meet all of the following three conditions? The wetland is larger than 1/10 ac (4350 ft2) Yes = Category I No = Category II SC 6.0. Interdunal Wetlands In practical terms that means the following geographic areas: Long Beach Peninsula: Lands west of SR 103 Grayland-Westport: Lands west of SR 105 Ocean Shores-Copalis: Lands west of SR 115 and SR 109 Yes - Go to SC 6.1 No = Not an interdunal wetland for rating SC 6.1. Yes = Category I No - Go to SC 6.2 SC 6.2.Is the wetland 1 ac or larger, or is it in a mosaic of wetlands that is 1 ac or larger? Yes = Category II No - Go to SC 6.3 SC 6.3. Yes = Category III No = Category IV Category of wetland based on Special Characteristics If you answered No for all types, enter “Not Applicable” on Summary Form The wetland is relatively undisturbed (has no diking, ditching, filling, cultivation, grazing), and has less than 20% cover of aggressive, opportunistic plant species (see list of species on p. 100). At least ¾ of the landward edge of the wetland has a 100 ft buffer of shrub, forest, or un- grazed or un-mowed grassland. Is the wetland west of the 1889 line (also called the Western Boundary of Upland Ownership or WBUO)? If you answer yes you will still need to rate the wetland based on its habitat functions. Is the wetland 1 ac or larger and scores an 8 or 9 for the habitat functions on the form (rates H,H,H or H,H,M for the three aspects of function)? Is the unit between 0.1 and 1 ac, or is it in a mosaic of wetlands that is between 0.1 and 1 ac? The wetland lies in a depression adjacent to marine waters that is wholly or partially separated from marine waters by sandbanks, gravel banks, shingle, or, less frequently, rocks The lagoon in which the wetland is located contains ponded water that is saline or brackish (> 0.5 ppt) during most of the year in at least a portion of the lagoon (needs to be measured near the bottom ) Does the wetland have at least 1 contiguous acre of forest that meets one of these criteria for the WA Department of Fish and Wildlife’s forests as priority habitats? If you answer YES you will still need to rate the wetland based on its functions. Old-growth forests (west of Cascade crest): Stands of at least two tree species, forming a multi-layered canopy with occasional small openings; with at least 8 trees/ac (20 trees/ha) that are at least 200 years of age OR have a diameter at breast height (dbh) of 32 in (81 cm) or more. Mature forests (west of the Cascade Crest): Stands where the largest trees are 80- 200 years old OR the species that make up the canopy have an average diameter (dbh) exceeding 21 in (53 cm). Soundview Consultants LLC June 22, 2017 1413.0004 – East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Appendix F – Qualifications Jeremy Downs, Principle Scientist/Environmental Planner Jeremy Downs is a Principal Scientist and Environmental Planner with professional training and extensive experience in land use, site planning and design, project coordination, permitting and management, marine and wetland ecology, habitat restoration, wetland, stream, and benthic delineations and assessments, stream assessments, underwater and terrestrial monitoring programs, and mitigation planning and design since 1987. Mr. Downs earned a Bachelor of Science degree in Biology from the University of California, Davis. In addition, he studied under the Environmental Risk and Recovery program at the Australian Institute of Marine Science. Mr. Downs also holds graduate-level professional certifications in various advanced wetland science and management programs from both Portland State University and San Francisco State University, and he has received professional training in Salmonid Biology from the University of California Extension. Jeremy is a certified wetlands delineator under US Army Corps of Engineers guidelines. He has been formally trained in the use of the Washington State Wetland Rating System, Determination of Ordinary High Water Mark, Designing Compensatory Mitigation and Restoration Projects, and Reviewing Wetland Mitigation and Monitoring Plans from the US Army Corps of Engineers and Washington State Department of Ecology, and in conducting Biological Assessments from the Washington Department of Transportation. Mr. Downs is also a Pierce County Qualified Wetland Specialist and Fisheries Biologist, and he holds similar qualifications from other jurisdictions. Jon Pickett, Senior Scientist/Environmental Planner Jon Pickett is a Senior Scientist/Environmental Planner with diverse professional experience in habitat development as a Regional Biologist and Environmental Project Manager, with an emphasis in wetland restoration and enhancement. Jon has extensive experience successfully planning, developing, securing funding, managing and implementing numerous large-scale wetland habitat projects aimed at restoring the biological and physical functions of wetlands throughout California’s Central Valley and Southern California. He worked to ensure the projects were designed and implemented to achieve habitat restoration goals, including reclamation of wetland and floodplain habitats, reintroduction of aquatic complexity and habitat, and reestablishment of riparian corridor. Jon also managed regulatory coordination to ensure projects operated in compliance with Federal, State and local environmental regulations, preparing permit documentation, coordinating with all pertinent agencies and stakeholders, and developing and maintaining appropriate permitting timelines to ensure timely approvals. He oversaw earthwork construction components and revegetation efforts, as well as post- project monitoring, with an emphasis in native vegetation establishment and natural channel morphology. Jon managed a 2,200 acre private wetland and upland habitat complex as a public trust resource for conservation and consumptive use. Jon has worked with Federal and State agencies and private entities on land acquisitions for conservational habitat and public use, including prioritizing acquisitions relative to value and opportunity and funding. Soundview Consultants LLC June 22, 2017 1413.0004 – East Valley Road - Wetland and Fish and Wildlife Habitat Assessment Emily Swaim, Wetland Scientist/Field Geologist Emily Swaim is a Wetland Scientist and Field Geologist with a background in delineating and assessing wetland and aquatic systems, conducting Phase I, II and III Environmental Site Assessments (ESAs), underground natural gas pipeline and overhead electrical transmission line project assessment and environmental inspections, construction oversight, stormwater compliance inspections, soil sampling, and stormwater, floodplain, and wetland permitting. Ms. Swaim’s expertise focuses on projects involving sensitive wetland and stream habitats where extensive team coordination and various regulatory challenges must be carefully and intelligently managed from project inception to completion. Emily earned a Bachelor of Science degree in Geology from Illinois State University and is also educated in Environmental Science from Iowa State University. She also studied Wetland Science and Management at the University of Washington in the Professional Continuing Education Certification Program to further enhance her professional capabilities and wetland science knowledge. Her education and experience has provided her with extensive knowledge on soils, wetland science, restoration and field botany, hydrogeology, sedimentology, environmental and wetland law, environmental geology, landscape ecology, and structural geology. Ms. Swaim has been formally trained in the use of the Washington State Wetland Rating System for Western Washington, determination of the Ordinary High Mark, identification of Wetlands of High Conservation Value, Grass, Sedge, and Rush identification, and how to choose Mitigation Sites based on a Watershed Approach. She is also formally trained in Hazardous Waste Operations and Emergency Response (HAZWOPER) and is also Occupational Health and Safety Administration (OSHA) 30-hour Construction and 10-hour Construction certified. She also has extensive experience in environmental compliance monitoring involving final site restoration efforts. Her former 115-mile 345 kV Electrical Transmission Line construction project won the Trumbull County Soil and Water Conservation District’s Project and Contractor of the Year Award in 2014 in regards to environmental compliance efforts that ensured regulatory compliance and successful project implementation. Ms. Swaim is a Pierce County Qualified Wetland Specialist. Melissa Cole, Staff Scientist Melissa Cole is a Staff Scientist with a background in research writing, project management, peer review, executing scopes of work, budgeting and financing, organizing and attending technical science seminars, public outreach, data entry and analysis, Phase I and Phase II environmental site assessments, soil sampling, soil vapor sampling, soil excavation monitoring, field classification of soils, stormwater surveying, water sampling, asbestos sampling, lead in water sampling, lead in paint sampling, noise monitoring, radon sampling, tree height / width and condition measurements, tree density measurements, seedling and sapling counting, analyzing grazing conditions, statistical analysis, and research presentation. Melissa received a Bachelor of Science degree from San Jose State University in Environmental Studies with a minor in Biology. This program provided her with a strong background in natural resource management, environmental laws and regulations, habitat conservation, and environmental restoration. Melissa’s interest in habitat conservation drove her to minor in Biological Science where she had courses in botany, zoology, computer literacy, biostatistical analysis, and ecology. DOWNSTREAM ANALYSIS MAP PROJECT SITE FLOW ARROWS STORMWATER EXITS SITE HERE 1/4 MILE DOWNSTREAM. STORMWATER IS STILL IN EAST VALLEY ROAD DRAINAGE SYSTEM Technical Information Report 2940, 2960, 2980, and 2990 East Valley Road Renton, WA 98057 2190112.10 Appendix C Exhibits C-1.................... Flood Insurance Rate Map C-2.................... Groundwater Protection Areas Map C-3.................... Department of Ecology GULD - Filterra PROJECT SITE PROJECT SITE 1 June 2016 GENERAL USE LEVEL DESIGNATION FOR BASIC (TSS), ENHANCED, PHOSPHORUS & OIL TREATMENT For Americast Filterra® BioscapeTM Ecology’s Decision: Based on Americast’s submissions, including the Final Technical Evaluation Reports, dated March 27, 2014, December 2009 and additional information provided to Ecology, Ecology hereby issues the following use level designations: 1. A General Use Level Designation for Basic, Enhanced, Phosphorus, and Oil Treatment at the following water quality design hydraulic loading rates: Treatment Hydraulic Conductivity* (in/hr) for use in Western Washington Sizing Infiltration Rate (in/hr) for use in eastern Washington Sizing Basic 70.92 100 Phosphorus 70.92 100 Oil 35.46 50 Enhanced 24.82 35 *calculated based on listed infiltration rate and a hydraulic gradient of 1.41 inch/inch (2.55 ft head with 1.80 ft media). 2. The Filterra® BioscapeTM unit is not appropriate for oil spill-control purposes. 3. Ecology approves the Filterra® BioscapeTM units for treatment at the hydraulic loading rates listed above, to achieve the maximum water quality design flow rate. Calculate the water quality design flow rates using the following procedures:  Western Washington: for treatment installed upstream of detention or retention, the water quality design flow rate is the peak 15-minute flow rate as calculated using the latest version of the Western Washington Hydrology Model or other Ecology-approved continuous runoff model. The model must indicate the unit (represented in the model by a sand filter element routed to a gravel trench bed) is capable of processing 91 percent of the influent runoff file.  Eastern Washington: For treatment installed upstream of detention or retention, the water quality design flow rate is the peak 15-minute flow rate as calculated using one of the three flow rate based methods described in Chapter 2.2.5 of the Stormwater Management Manual for Eastern Washington (SWMMEW) or local manual. 2  Entire State: For treatment installed downstream of detention, the water quality design flow rate is the full 2-year release rate of the detention facility. 4. This General Use Level Designation has no expiration date but Ecology may revoke or amend the designation, and is subject to the conditions specified below. Ecology’s Conditions of Use: Filterra® units shall comply with the following conditions: 1. Design, assemble, install, operate, and maintain the Filterra® BioscapeTM units in accordance with applicable Americast Filterra® manuals, document, and the Ecology Decision. 2. Each site plan must undergo Americast Filterra® review before Ecology can approve the unit for site installation. This will ensure that site grading and slope are appropriate for use of a Filterra® BioscapeTM unit. 3. Filterra® BioscapeTM media shall conform to the specifications submitted to and approved by Ecology. The media shall not differ from the media used in the standard Filterra unit and as approved by Ecology. 4. Maintenance includes removing trash, degraded mulch, and accumulated debris from the filter surface and replacing the mulch layer. Use inspections to determine the site-specific maintenance schedules and requirements. Follow maintenance procedures given in the most recent version of the Filterra® BioscapeTM Operation and Maintenance Manual. 5. Maintenance: The required maintenance interval for stormwater treatment devices is often dependent upon the degree of pollutant loading from a particular drainage basin. Therefore, Ecology does not endorse or recommend a “one size fits all” maintenance cycle for a particular model/size of manufactured filter treatment device.  Filterra designs their systems for a target maintenance interval of 6 months. Maintenance includes removing accumulated sediment and trash from the surface area of the media, removing the mulch above the media, replacing the mulch, providing plant health evaluation, and pruning the plant if deemed necessary.  Conduct maintenance following manufacturer’s guidelines. 6. The minimum size filter surface-area for use in western Washington is determined by using the sand filter element connected to a gravel trench bed element in the latest version of WWHM or other Ecology approved continuous runoff model. Sand Filter element model inputs include a. Filter media depth: 1.8 feet b. Effective Ponding Depth: 0.75 feet (This is equivalent to the 6-inch clear zone between the top of the mulch and the bottom of the slab plus 3-inches of mulch.) c. Side slopes: Vertical d. Riser height: 0.70 feet e. Filter Hydraulic Conductivity: Use the Hydraulic Conductivity as listed in the table above (use the lowest applicable hydraulic conductivity depending on the level of treatment required) under Ecology’s Decision, above. 3 Gravel Trench Bed element model inputs include: a. Outlet 2 (discharge through the bottom of the sand filter element) should be connected to the gravel trench bed b. Outlet 1 (surface discharge from the sand filter element) represents the overflow (bypass through the Terraflume weir tray in the flow splitter) and should not be connected to the gravel trench bed c. Trench length and width: same as the Filterra® Bioscape™ unit (modeled in the sand filter element) d. Effective total depth: 1.167 feet (includes 1 foot of freeboard) e. Bottom slope: 0.001 ft/ft (must be a non-zero input) f. Riser height: 0.167 feet (depth of aggregate layer below underdrain pipe) g. Layer 1 thickness: 0.167 feet h. Layer 1 porosity: 0.3 i. Infiltration: yes, if native soil infiltration is possible. Use short-term native soil infiltration rate with a safety factor of 4. 7. The minimum size filter surface-area for use in eastern Washington is determined by using the design water quality flow rate (as determined in item 3, above) and the Infiltration Rate from the above table (use the lowest applicable Infiltration Rate depending on the level of treatment required). Calculate the required area by dividing the water quality design flow rate (cu ft/sec) by the Infiltration Rate (converted to ft/sec) to obtain required surface area (sq ft) of the Filterra unit. 8. The distance from the point of entry of water to the most distant point on the surface of the Filterra® BioscapeTM treatment media shall not exceed 12-feet. The Filterra® BioscapeTM requires water to flow across the entire surface area to obtain optimal performance. 9. Users can design the Filterra® BioscapeTM units without an underdrain. Users shall design the system with a temporary water storage area beneath the treatment media to provide a detention reservoir. Water shall not saturate the treatment media at any time. 10. Discharges from the Filterra® units shall not cause or contribute to water quality standards violations in receiving waters. Applicant: Filterra® Bioretention Systems, division of Americast, Inc. Applicant’s Address: 11352 Virginia Precast Road Ashland, VA, 23005 Application Documents:  State of Washington Department of Ecology Application for Conditional Use Designation, Americast (September 2006)  Quality Assurance Project Plan Filterra® Bioretention Filtration System Performance Monitoring, Americast (April 2008)  Quality Assurance Project Plan Addendum Filterra® Bioretention Filtration System Performance Monitoring, Americast (June 2008) 4  Draft Technical Evaluation Report Filterra® Bioretention Filtration System Performance Monitoring, Americast (August 2009)  Final Technical Evaluation Report Filterra® Bioretention Filtration System Performance Monitoring, Americast (December 2009)  Technical Evaluation Report Appendices Filterra® Bioretention Filtration System Performance Monitoring, Americast (August 2009)  Memorandum to Department of Ecology Dated October 9, 2009 from Americast, Inc. and Herrera Environmental Consultants  Quality Assurance Project Plan Filterra® Bioretention System Phosphorus treatment and Supplemental Basic and Enhanced Treatment Performance Monitoring, Americast (November 2011)  Filterra® letter August 24, 2012 regarding sizing for the Filterra® Shallow System.  University of Virginia Engineering Department Memo by Joanna Crowe Curran, Ph. D dated March 16, 2013 concerning capacity analysis of Filterra® internal weir inlet tray.  Filterra® BioscapeTM Bioretention System Model Configuration Approval Request, January 2014  Terraphase Engineering letter to Jodi Mills, P.E. dated April 2, 2013 regarding Terraflume Hydraulic Test, Filterra® Bioretention System and attachments.  Technical Evaluation Report, Filterra® System Phosphorus Treatment and Supplemental Basic Treatment Performance Monitoring. March 27th, 2014. Applicant’s Use Level Request: General Level Use Designation for Basic, Enhanced, Phosphorus, and Oil Treatment. Applicant’s Performance Claims: Field-testing and laboratory testing show that the Filterra® unit is promising as a stormwater treatment best management practice and can meet Ecology’s performance goals for basic, enhanced, phosphorus, and oil treatment. Findings of Fact: Field Testing 2013 1. Filterra® completed field-testing of a 6.5 ft x 4 ft. unit at one site in Bellingham, Washington. Continuous flow and rainfall data collected from January 1, 2013 through July 23, 2013 indicated that 59 storm events occurred. The monitoring obtained water quality data from 22 storm events. Not all the sampled storms produced information that met TAPE criteria for storm and/or water quality data. 2. The system treated 98.9 percent of the total 8-month runoff volume during the testing period. Consequently, the system achieved the goal of treating 91 percent of the volume from the site. Stormwater runoff bypassed during four of the 59 storm events. 5 3. Of the 22 sampled events, 18 qualified for TSS analysis (influent TSS concentrations ranged from 25 to 138 mg/L). The data were segregated into sample pairs with influent concentration greater than and less than 100 mg/L. The UCL95 mean effluent concentration for the data with influent less than 100 mg/L was 5.2 mg/L, below the 20- mg/L threshold. Although the TAPE guidelines do not require an evaluation of TSS removal efficiency for influent concentrations below 100 mg/L, the mean TSS removal for these samples was 90.1 percent. Average removal of influent TSS concentrations greater than 100 mg/L (three events) was 85 percent. In addition, the system consistently exhibited TSS removal greater than 80 percent at flow rates at a 100 inches per hour [in/hr] infiltration rate and was observed at 150 in/hr. 4. Ten of the 22 sampled events qualified for TP analysis. Americast augmented the dataset using two sample pairs from previous monitoring at the site. Influent TP concentrations ranged from 0.11 to 0.52 mg/L. The mean TP removal for these twelve events was 72.6 percent. The LCL95 mean percent removal was 66.0, well above the TAPE requirement of 50 percent. Treatment above 50 percent was evident at 100 in/hr infiltration rate and as high as 150 in/hr. Consequently, the Filterra® test system met the TAPE Phosphorus Treatment goal at 100 in/hr. Influent ortho-P concentrations ranged from 0.005 to 0.012 mg/L; effluent ortho-P concentrations ranged from 0.005 to 0.013 mg/L. The reporting limit/resolution for the ortho-P test method is 0.01 mg/L, therefore the influent and effluent ortho-P concentrations were both at or near non-detect concentrations. Field Testing 2008-2009 1. Filterra® completed field-testing at two sites at the Port of Tacoma. Continuous flow and rainfall data collected during the 2008-2009 monitoring period indicated that 89 storm events occurred. The monitoring obtained water quality data from 27 storm events. Not all the sampled storms produced information that met TAPE criteria for storm and/or water quality data. 2. During the testing at the Port of Tacoma, 98.96 to 99.89 percent of the annual influent runoff volume passed through the POT1 and POT2 test systems respectively. Stormwater runoff bypassed the POT1 test system during nine storm events and bypassed the POT2 test system during one storm event. Bypass volumes ranged from 0.13% to 15.3% of the influent storm volume. Both test systems achieved the 91 percent water quality treatment-goal over the 1-year monitoring period. 3. Consultants observed infiltration rates as high as 133 in/hr during the various storms. Filterra® did not provide any paired data that identified percent removal of TSS, metals, oil, or phosphorus at an instantaneous observed flow rate. 4. The maximum storm average hydraulic loading rate associated with water quality data is <40 in/hr, with the majority of flow rates < 25 in/hr. The average instantaneous hydraulic loading rate ranged from 8.6 to 53 inches per hour. 5. The field data showed a removal rate greater than 80% for TSS with an influent concentration greater than 20 mg/l at an average instantaneous hydraulic loading rate up to 53 in/hr (average influent concentration of 28.8 mg/l, average effluent concentration of 4.3 mg/l). 6 6. The field data showed a removal rate generally greater than 54% for dissolved zinc at an average instantaneous hydraulic loading rate up to 60 in/hr and an average influent concentration of 0.266 mg/l (average effluent concentration of 0.115 mg/l). 7. The field data showed a removal rate generally greater than 40% for dissolved copper at an average instantaneous hydraulic loading rate up to 35 in/hr and an average influent concentration of 0.0070 mg/l (average effluent concentration of 0.0036 mg/l). 8. The field data showed an average removal rate of 93% for total petroleum hydrocarbon (TPH) at an average instantaneous hydraulic loading rate up to 53 in/hr and an average influent concentration of 52 mg/l (average effluent concentration of 2.3 mg/l). The data also shows achievement of less than 15 mg/l TPH for grab samples. Filterra® provided limited visible sheen data due to access limitations at the outlet monitoring location. 9. The field data showed low percentage removals of total phosphorus at all storm flows at an average influent concentration of 0.189 mg/l (average effluent concentration of 0.171 mg/l). We may relate the relatively poor treatment performance of the Filterra® system at this location to influent characteristics for total phosphorus that are unique to the Port of Tacoma site. It appears that the Filterra® system will not meet the 50 percent removal performance goal when you expect the majority of phosphorus in the runoff to be in the dissolved form. Laboratory Testing 1. Filterra® performed laboratory testing on a scaled down version of the Filterra® unit. The lab data showed an average removal from 83-91% for TSS with influents ranging from 21 to 320 mg/L, 82-84% for total copper with influents ranging from 0.94 to 2.3 mg/L, and 50-61% for orthophosphate with influents ranging from 2.46 to 14.37 mg/L. 2. Filterra® conducted permeability tests on the soil media. 3. Lab scale testing using Sil-Co-Sil 106 showed percent removals ranging from 70.1% to 95.5% with a median percent removal of 90.7%, for influent concentrations ranging from 8.3 to 260 mg/L. Filterra® ran these laboratory tests at an infiltration rate of 50 in/hr. 4. Supplemental lab testing conducted in September 2009 using Sil-Co-Sil 106 showed an average percent removal of 90.6%. These laboratory tests were run at infiltration rates ranging from 25 to 150 in/hr for influent concentrations ranging from 41.6 to 252.5 mg/l. Regression analysis results indicate that the Filterra® system’s TSS removal performance is independent of influent concentration in the concentration rage evaluated at hydraulic loading rates of up to 150 in/hr. 7 Contact Information: Applicant: Sean Darcy Contech Engineered Solutions, LLC. 11815 Glenn Widing Dr Portland, OR 97220 (503) 258-3105 darcys@conteches.com Applicant’s Website: http://www.conteches.com Ecology web link: http://www.ecy.wa.gov/programs/wq/stormwater/newtech/index.html Ecology: Douglas C. Howie, P.E. Department of Ecology Water Quality Program (360) 407-6444 douglas.howie@ecy.wa.gov Date Revision July 2014 GULD for Basic, Enhanced, Phosphorus and Oil granted March 2015 Revised Contact Information December 2015 Revised device name from Filterra® BoxlessTM to Filterra®BioscapeTM June 2016 Revised text regarding Hydraulic conductivity value Note: Some pages in this document have been purposely skipped or blank pages inserted so that this document will copy correctly when duplexed. Technical Information Report 2940, 2960, 2980, and 2990 East Valley Road Renton, WA 98057 2190112.10 Appendix D Exhibits D-1.................... Flow Control Application Map D-2.................... WWHM Flow Control Calculations D-3.................... 25-Year Conveyance Simulation D-4.................... Filterra Sizing Calculations PROJECT SITE WWHM2012 PROJECT REPORT D-2 Flow Control Calculations 20190226-Flow Control Calcs 2/26/2019 1:02:39 PM Page 2 General Model Information Project Name:20190226-Flow Control Calcs Site Name: Site Address: City: Report Date:2/26/2019 Gage:Seatac Data Start:1948/10/01 Data End:2009/09/30 Timestep:15 Minute Precip Scale:1.000 Version Date:2017/07/05 Version:4.2.13 POC Thresholds Low Flow Threshold for POC1:50 Percent of the 2 Year High Flow Threshold for POC1:50 Year 20190226-Flow Control Calcs 2/26/2019 1:02:39 PM Page 3 Landuse Basin Data Predeveloped Land Use PreDeveloped Condition Bypass:No GroundWater:No Pervious Land Use acre C, Forest, Flat 0.09 SAT, Forest, Flat 0.16 Pervious Total 0.25 Impervious Land Use acre DRIVEWAYS FLAT 4.03 Impervious Total 4.03 Basin Total 4.28 Element Flows To: Surface Interflow Groundwater 20190226-Flow Control Calcs 2/26/2019 1:02:39 PM Page 4 Mitigated Land Use Developed Condition Bypass:No GroundWater:No Pervious Land Use acre C, Lawn, Flat 1.37 SAT, Forest, Flat 0.16 Pervious Total 1.53 Impervious Land Use acre DRIVEWAYS FLAT 2.75 Impervious Total 2.75 Basin Total 4.28 Element Flows To: Surface Interflow Groundwater 20190226-Flow Control Calcs 2/26/2019 1:02:39 PM Page 5 Routing Elements Predeveloped Routing 20190226-Flow Control Calcs 2/26/2019 1:02:39 PM Page 6 Mitigated Routing 20190226-Flow Control Calcs 2/26/2019 1:02:39 PM Page 7 Analysis Results POC 1 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area:0.25 Total Impervious Area:4.03 Mitigated Landuse Totals for POC #1 Total Pervious Area:1.53 Total Impervious Area:2.75 Flow Frequency Method:Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 1.540876 5 year 1.944946 10 year 2.219336 25 year 2.575109 50 year 2.847308 100 year 3.126035 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 1.140055 5 year 1.475202 10 year 1.70718 25 year 2.012509 50 year 2.249212 100 year 2.494107 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1949 1.995 1.559 1950 2.150 1.499 1951 1.267 0.989 1952 1.106 0.770 1953 1.194 0.832 1954 1.257 0.932 1955 1.418 1.030 1956 1.397 1.021 1957 1.588 1.214 1958 1.277 0.920 20190226-Flow Control Calcs 2/26/2019 1:03:28 PM Page 8 1959 1.302 0.889 1960 1.290 1.014 1961 1.363 1.028 1962 1.177 0.832 1963 1.311 0.987 1964 1.282 0.923 1965 1.645 1.275 1966 1.094 0.795 1967 1.877 1.411 1968 2.134 1.575 1969 1.486 1.147 1970 1.434 1.064 1971 1.708 1.268 1972 1.781 1.439 1973 1.067 0.729 1974 1.558 1.185 1975 1.794 1.226 1976 1.215 0.922 1977 1.307 0.894 1978 1.598 1.121 1979 2.188 1.518 1980 1.965 1.614 1981 1.606 1.175 1982 2.265 1.716 1983 1.843 1.307 1984 1.173 0.867 1985 1.602 1.179 1986 1.389 0.984 1987 2.142 1.506 1988 1.300 0.887 1989 1.625 1.110 1990 2.751 2.388 1991 2.193 1.815 1992 1.154 0.851 1993 0.998 0.710 1994 1.085 0.740 1995 1.424 1.033 1996 1.528 1.210 1997 1.486 1.148 1998 1.491 1.062 1999 3.051 2.355 2000 1.526 1.143 2001 1.669 1.165 2002 1.948 1.535 2003 1.518 1.195 2004 2.855 2.182 2005 1.315 1.011 2006 1.163 0.912 2007 2.668 2.154 2008 2.172 1.799 2009 1.986 1.359 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 3.0512 2.3881 2 2.8550 2.3547 3 2.7512 2.1824 20190226-Flow Control Calcs 2/26/2019 1:03:28 PM Page 9 4 2.6685 2.1541 5 2.2647 1.8153 6 2.1928 1.7990 7 2.1879 1.7161 8 2.1716 1.6137 9 2.1505 1.5752 10 2.1424 1.5590 11 2.1342 1.5345 12 1.9949 1.5183 13 1.9860 1.5058 14 1.9650 1.4991 15 1.9475 1.4386 16 1.8770 1.4111 17 1.8428 1.3590 18 1.7942 1.3068 19 1.7811 1.2749 20 1.7081 1.2680 21 1.6688 1.2255 22 1.6447 1.2139 23 1.6255 1.2096 24 1.6064 1.1952 25 1.6022 1.1849 26 1.5983 1.1787 27 1.5875 1.1748 28 1.5584 1.1650 29 1.5277 1.1484 30 1.5264 1.1472 31 1.5178 1.1428 32 1.4915 1.1214 33 1.4861 1.1096 34 1.4859 1.0635 35 1.4343 1.0623 36 1.4245 1.0331 37 1.4180 1.0303 38 1.3965 1.0282 39 1.3885 1.0206 40 1.3632 1.0137 41 1.3153 1.0109 42 1.3106 0.9892 43 1.3066 0.9868 44 1.3016 0.9840 45 1.2997 0.9321 46 1.2904 0.9233 47 1.2824 0.9222 48 1.2773 0.9198 49 1.2673 0.9125 50 1.2566 0.8942 51 1.2147 0.8891 52 1.1942 0.8871 53 1.1772 0.8670 54 1.1728 0.8512 55 1.1633 0.8323 56 1.1537 0.8321 57 1.1058 0.7954 58 1.0943 0.7698 59 1.0847 0.7403 60 1.0673 0.7288 61 0.9976 0.7105 20190226-Flow Control Calcs 2/26/2019 1:03:28 PM Page 10 20190226-Flow Control Calcs 2/26/2019 1:03:28 PM Page 11 Duration Flows The Facility PASSED Flow(cfs)Predev Mit Percentage Pass/Fail 0.7704 1808 554 30 Pass 0.7914 1648 508 30 Pass 0.8124 1487 455 30 Pass 0.8334 1360 412 30 Pass 0.8544 1232 378 30 Pass 0.8753 1116 357 31 Pass 0.8963 1011 324 32 Pass 0.9173 927 297 32 Pass 0.9383 859 271 31 Pass 0.9592 790 245 31 Pass 0.9802 730 224 30 Pass 1.0012 672 204 30 Pass 1.0222 612 189 30 Pass 1.0432 573 171 29 Pass 1.0641 541 159 29 Pass 1.0851 493 145 29 Pass 1.1061 453 135 29 Pass 1.1271 424 126 29 Pass 1.1481 393 111 28 Pass 1.1690 372 105 28 Pass 1.1900 341 101 29 Pass 1.2110 321 93 28 Pass 1.2320 299 84 28 Pass 1.2529 276 82 29 Pass 1.2739 259 77 29 Pass 1.2949 241 76 31 Pass 1.3159 223 70 31 Pass 1.3369 210 65 30 Pass 1.3578 199 61 30 Pass 1.3788 183 58 31 Pass 1.3998 172 55 31 Pass 1.4208 160 50 31 Pass 1.4417 146 46 31 Pass 1.4627 140 43 30 Pass 1.4837 136 39 28 Pass 1.5047 124 37 29 Pass 1.5257 116 32 27 Pass 1.5466 107 29 27 Pass 1.5676 105 27 25 Pass 1.5886 100 26 26 Pass 1.6096 92 22 23 Pass 1.6306 88 21 23 Pass 1.6515 83 20 24 Pass 1.6725 76 18 23 Pass 1.6935 71 17 23 Pass 1.7145 66 15 22 Pass 1.7354 64 13 20 Pass 1.7564 62 12 19 Pass 1.7774 59 12 20 Pass 1.7984 55 11 20 Pass 1.8194 53 8 15 Pass 1.8403 53 8 15 Pass 1.8613 50 8 16 Pass 20190226-Flow Control Calcs 2/26/2019 1:03:28 PM Page 12 1.8823 48 8 16 Pass 1.9033 45 8 17 Pass 1.9243 40 7 17 Pass 1.9452 38 7 18 Pass 1.9662 33 7 21 Pass 1.9872 31 7 22 Pass 2.0082 29 7 24 Pass 2.0291 28 7 25 Pass 2.0501 25 7 28 Pass 2.0711 23 6 26 Pass 2.0921 21 5 23 Pass 2.1131 21 5 23 Pass 2.1340 17 5 29 Pass 2.1550 14 4 28 Pass 2.1760 12 3 25 Pass 2.1970 9 2 22 Pass 2.2180 9 2 22 Pass 2.2389 9 2 22 Pass 2.2599 9 2 22 Pass 2.2809 8 2 25 Pass 2.3019 8 2 25 Pass 2.3228 8 2 25 Pass 2.3438 8 2 25 Pass 2.3648 8 1 12 Pass 2.3858 8 1 12 Pass 2.4068 8 0 0 Pass 2.4277 8 0 0 Pass 2.4487 8 0 0 Pass 2.4697 7 0 0 Pass 2.4907 7 0 0 Pass 2.5117 7 0 0 Pass 2.5326 7 0 0 Pass 2.5536 6 0 0 Pass 2.5746 6 0 0 Pass 2.5956 6 0 0 Pass 2.6165 6 0 0 Pass 2.6375 6 0 0 Pass 2.6585 6 0 0 Pass 2.6795 5 0 0 Pass 2.7005 5 0 0 Pass 2.7214 4 0 0 Pass 2.7424 4 0 0 Pass 2.7634 3 0 0 Pass 2.7844 2 0 0 Pass 2.8054 2 0 0 Pass 2.8263 2 0 0 Pass 2.8473 2 0 0 Pass 20190226-Flow Control Calcs 2/26/2019 1:03:28 PM Page 13 Water Quality Water Quality BMP Flow and Volume for POC #1 On-line facility volume:0 acre-feet On-line facility target flow:0 cfs. Adjusted for 15 min:0 cfs. Off-line facility target flow:0 cfs. Adjusted for 15 min:0 cfs. 20190226-Flow Control Calcs 2/26/2019 1:03:28 PM Page 14 LID Report 20190226-Flow Control Calcs 2/26/2019 1:04:11 PM Page 15 POC 2 POC #2 was not reported because POC must exist in both scenarios and both scenarios must have been run. 20190226-Flow Control Calcs 2/26/2019 1:04:11 PM Page 16 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. 20190226-Flow Control Calcs 2/26/2019 1:04:11 PM Page 17 Appendix Predeveloped Schematic 20190226-Flow Control Calcs 2/26/2019 1:04:13 PM Page 18 Mitigated Schematic 20190226-Flow Control Calcs 2/26/2019 1:04:14 PM Page 19 Predeveloped UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END 2009 09 30 RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 UNIT SYSTEM 1 END GLOBAL FILES <File> <Un#> <-----------File Name------------------------------>*** <-ID-> *** WDM 26 20190226-Flow Control Calcs.wdm MESSU 25 Pre20190226-Flow Control Calcs.MES 27 Pre20190226-Flow Control Calcs.L61 28 Pre20190226-Flow Control Calcs.L62 30 POC20190226-Flow Control Calcs1.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 10 PERLND 19 IMPLND 5 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 PreDeveloped Condition MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 END TIMESERIES END COPY GENER OPCODE # # OPCD *** END OPCODE PARM # # K *** END PARM END GENER PERLND GEN-INFO <PLS ><-------Name------->NBLKS Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 10 C, Forest, Flat 1 1 1 1 27 0 19 SAT, Forest, Flat 1 1 1 1 27 0 END GEN-INFO *** Section PWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC *** 10 0 0 1 0 0 0 0 0 0 0 0 0 19 0 0 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ***************************** PIVL PYR 20190226-Flow Control Calcs 2/26/2019 1:04:14 PM Page 20 # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC ********* 10 0 0 4 0 0 0 0 0 0 0 0 0 1 9 19 0 0 4 0 0 0 0 0 0 0 0 0 1 9 END PRINT-INFO PWAT-PARM1 <PLS > PWATER variable monthly parameter value flags *** # - # CSNO RTOP UZFG VCS VUZ VNN VIFW VIRC VLE INFC HWT *** 10 0 0 0 0 0 0 0 0 0 0 0 19 0 0 0 0 0 0 0 0 0 0 0 END PWAT-PARM1 PWAT-PARM2 <PLS > PWATER input info: Part 2 *** # - # ***FOREST LZSN INFILT LSUR SLSUR KVARY AGWRC 10 0 4.5 0.08 400 0.05 0.5 0.996 19 0 4 2 100 0.001 0.5 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 10 0 0 2 2 0 0 0 19 0 0 10 2 0 0 0.7 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 10 0.2 0.5 0.35 6 0.5 0.7 19 0.2 3 0.5 1 0.7 0.8 END PWAT-PARM4 PWAT-STATE1 <PLS > *** Initial conditions at start of simulation ran from 1990 to end of 1992 (pat 1-11-95) RUN 21 *** # - # *** CEPS SURS UZS IFWS LZS AGWS GWVS 10 0 0 0 0 2.5 1 0 19 0 0 0 0 4.2 1 0 END PWAT-STATE1 END PERLND IMPLND GEN-INFO <PLS ><-------Name-------> Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 5 DRIVEWAYS/FLAT 1 1 1 27 0 END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** 5 0 0 1 0 0 0 END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* 5 0 0 4 0 0 0 1 9 END PRINT-INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** 5 0 0 0 0 0 END IWAT-PARM1 IWAT-PARM2 20190226-Flow Control Calcs 2/26/2019 1:04:14 PM Page 21 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC 5 400 0.01 0.1 0.1 END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN 5 0 0 END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 5 0 0 END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** PreDeveloped Condition*** PERLND 10 0.09 COPY 501 12 PERLND 10 0.09 COPY 501 13 PERLND 19 0.16 COPY 501 12 PERLND 19 0.16 COPY 501 13 IMPLND 5 4.03 COPY 501 15 ******Routing****** END SCHEMATIC NETWORK <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** COPY 501 OUTPUT MEAN 1 1 48.4 DISPLY 1 INPUT TIMSER 1 <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** END NETWORK RCHRES GEN-INFO RCHRES Name Nexits Unit Systems Printer *** # - #<------------------><---> User T-series Engl Metr LKFG *** in out *** END GEN-INFO *** Section RCHRES*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG *** END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ******************* PIVL PYR # - # HYDR ADCA CONS HEAT SED GQL OXRX NUTR PLNK PHCB PIVL PYR ********* END PRINT-INFO HYDR-PARM1 RCHRES Flags for each HYDR Section *** # - # VC A1 A2 A3 ODFVFG for each *** ODGTFG for each FUNCT for each FG FG FG FG possible exit *** possible exit possible exit * * * * * * * * * * * * * * *** END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** 20190226-Flow Control Calcs 2/26/2019 1:04:14 PM Page 22 <------><--------><--------><--------><--------><--------><--------> *** END HYDR-PARM2 HYDR-INIT RCHRES Initial conditions for each HYDR section *** # - # *** VOL Initial value of COLIND Initial value of OUTDGT *** ac-ft for each possible exit for each possible exit <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> END HYDR-INIT END RCHRES SPEC-ACTIONS END SPEC-ACTIONS FTABLES END FTABLES EXT SOURCES <-Volume-> <Member> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # tem strg<-factor->strg <Name> # # <Name> # # *** WDM 2 PREC ENGL 1 PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1 IMPLND 1 999 EXTNL PREC WDM 1 EVAP ENGL 0.76 PERLND 1 999 EXTNL PETINP WDM 1 EVAP ENGL 0.76 IMPLND 1 999 EXTNL PETINP END EXT SOURCES EXT TARGETS <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Volume-> <Member> Tsys Tgap Amd *** <Name> # <Name> # #<-factor->strg <Name> # <Name> tem strg strg*** COPY 501 OUTPUT MEAN 1 1 48.4 WDM 501 FLOW ENGL REPL END EXT TARGETS MASS-LINK <Volume> <-Grp> <-Member-><--Mult--> <Target> <-Grp> <-Member->*** <Name> <Name> # #<-factor-> <Name> <Name> # #*** MASS-LINK 12 PERLND PWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 12 MASS-LINK 13 PERLND PWATER IFWO 0.083333 COPY INPUT MEAN END MASS-LINK 13 MASS-LINK 15 IMPLND IWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 15 END MASS-LINK END RUN 20190226-Flow Control Calcs 2/26/2019 1:04:14 PM Page 23 Mitigated UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END 2009 09 30 RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 UNIT SYSTEM 1 END GLOBAL FILES <File> <Un#> <-----------File Name------------------------------>*** <-ID-> *** WDM 26 20190226-Flow Control Calcs.wdm MESSU 25 Mit20190226-Flow Control Calcs.MES 27 Mit20190226-Flow Control Calcs.L61 28 Mit20190226-Flow Control Calcs.L62 30 POC20190226-Flow Control Calcs1.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 16 PERLND 19 IMPLND 5 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 Developed Condition MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 END TIMESERIES END COPY GENER OPCODE # # OPCD *** END OPCODE PARM # # K *** END PARM END GENER PERLND GEN-INFO <PLS ><-------Name------->NBLKS Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 16 C, Lawn, Flat 1 1 1 1 27 0 19 SAT, Forest, Flat 1 1 1 1 27 0 END GEN-INFO *** Section PWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC *** 16 0 0 1 0 0 0 0 0 0 0 0 0 19 0 0 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ***************************** PIVL PYR 20190226-Flow Control Calcs 2/26/2019 1:04:14 PM Page 24 # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC ********* 16 0 0 4 0 0 0 0 0 0 0 0 0 1 9 19 0 0 4 0 0 0 0 0 0 0 0 0 1 9 END PRINT-INFO PWAT-PARM1 <PLS > PWATER variable monthly parameter value flags *** # - # CSNO RTOP UZFG VCS VUZ VNN VIFW VIRC VLE INFC HWT *** 16 0 0 0 0 0 0 0 0 0 0 0 19 0 0 0 0 0 0 0 0 0 0 0 END PWAT-PARM1 PWAT-PARM2 <PLS > PWATER input info: Part 2 *** # - # ***FOREST LZSN INFILT LSUR SLSUR KVARY AGWRC 16 0 4.5 0.03 400 0.05 0.5 0.996 19 0 4 2 100 0.001 0.5 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 16 0 0 2 2 0 0 0 19 0 0 10 2 0 0 0.7 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 16 0.1 0.25 0.25 6 0.5 0.25 19 0.2 3 0.5 1 0.7 0.8 END PWAT-PARM4 PWAT-STATE1 <PLS > *** Initial conditions at start of simulation ran from 1990 to end of 1992 (pat 1-11-95) RUN 21 *** # - # *** CEPS SURS UZS IFWS LZS AGWS GWVS 16 0 0 0 0 2.5 1 0 19 0 0 0 0 4.2 1 0 END PWAT-STATE1 END PERLND IMPLND GEN-INFO <PLS ><-------Name-------> Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 5 DRIVEWAYS/FLAT 1 1 1 27 0 END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** 5 0 0 1 0 0 0 END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* 5 0 0 4 0 0 0 1 9 END PRINT-INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** 5 0 0 0 0 0 END IWAT-PARM1 IWAT-PARM2 20190226-Flow Control Calcs 2/26/2019 1:04:14 PM Page 25 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC 5 400 0.01 0.1 0.1 END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN 5 0 0 END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 5 0 0 END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Developed Condition*** PERLND 16 1.37 COPY 501 12 PERLND 16 1.37 COPY 501 13 PERLND 19 0.16 COPY 501 12 PERLND 19 0.16 COPY 501 13 IMPLND 5 2.75 COPY 501 15 ******Routing****** END SCHEMATIC NETWORK <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** COPY 501 OUTPUT MEAN 1 1 48.4 DISPLY 1 INPUT TIMSER 1 <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** END NETWORK RCHRES GEN-INFO RCHRES Name Nexits Unit Systems Printer *** # - #<------------------><---> User T-series Engl Metr LKFG *** in out *** END GEN-INFO *** Section RCHRES*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG *** END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ******************* PIVL PYR # - # HYDR ADCA CONS HEAT SED GQL OXRX NUTR PLNK PHCB PIVL PYR ********* END PRINT-INFO HYDR-PARM1 RCHRES Flags for each HYDR Section *** # - # VC A1 A2 A3 ODFVFG for each *** ODGTFG for each FUNCT for each FG FG FG FG possible exit *** possible exit possible exit * * * * * * * * * * * * * * *** END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** 20190226-Flow Control Calcs 2/26/2019 1:04:14 PM Page 26 <------><--------><--------><--------><--------><--------><--------> *** END HYDR-PARM2 HYDR-INIT RCHRES Initial conditions for each HYDR section *** # - # *** VOL Initial value of COLIND Initial value of OUTDGT *** ac-ft for each possible exit for each possible exit <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> END HYDR-INIT END RCHRES SPEC-ACTIONS END SPEC-ACTIONS FTABLES END FTABLES EXT SOURCES <-Volume-> <Member> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # tem strg<-factor->strg <Name> # # <Name> # # *** WDM 2 PREC ENGL 1 PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1 IMPLND 1 999 EXTNL PREC WDM 1 EVAP ENGL 0.76 PERLND 1 999 EXTNL PETINP WDM 1 EVAP ENGL 0.76 IMPLND 1 999 EXTNL PETINP END EXT SOURCES EXT TARGETS <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Volume-> <Member> Tsys Tgap Amd *** <Name> # <Name> # #<-factor->strg <Name> # <Name> tem strg strg*** COPY 1 OUTPUT MEAN 1 1 48.4 WDM 701 FLOW ENGL REPL COPY 501 OUTPUT MEAN 1 1 48.4 WDM 801 FLOW ENGL REPL END EXT TARGETS MASS-LINK <Volume> <-Grp> <-Member-><--Mult--> <Target> <-Grp> <-Member->*** <Name> <Name> # #<-factor-> <Name> <Name> # #*** MASS-LINK 12 PERLND PWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 12 MASS-LINK 13 PERLND PWATER IFWO 0.083333 COPY INPUT MEAN END MASS-LINK 13 MASS-LINK 15 IMPLND IWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 15 END MASS-LINK END RUN 20190226-Flow Control Calcs 2/26/2019 1:04:14 PM Page 27 Predeveloped HSPF Message File 20190226-Flow Control Calcs 2/26/2019 1:04:14 PM Page 28 Mitigated HSPF Message File 20190226-Flow Control Calcs 2/26/2019 1:04:14 PM Page 29 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. 2005-2019; 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 Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.010 Channel Slope 0.00500 ft/ft Diameter 1.00 ft Discharge 2.02 ft³/s Results Normal Depth 0.57 ft Flow Area 0.46 ft² Wetted Perimeter 1.71 ft Hydraulic Radius 0.27 ft Top Width 0.99 ft Critical Depth 0.61 ft Percent Full 56.8 % Critical Slope 0.00407 ft/ft Velocity 4.39 ft/s Velocity Head 0.30 ft Specific Energy 0.87 ft Froude Number 1.13 Maximum Discharge 3.52 ft³/s Discharge Full 3.27 ft³/s Slope Full 0.00190 ft/ft Flow Type SuperCritical GVF Input Data Downstream Depth 0.00 ft Length 0.00 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.00 ft Profile Description Profile Headloss 0.00 ft Average End Depth Over Rise 0.00 % Normal Depth Over Rise 56.80 % Downstream Velocity Infinity ft/s Worksheet for Circular Pipe - 1 2/26/2019 1:15:59 PM Bentley Systems, Inc. Haestad Methods Solution CenterBentley FlowMaster V8i (SELECTseries 1) [08.11.01.03] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 2of1Page 25 year storm from WWHM GVF Output Data Upstream Velocity Infinity ft/s Normal Depth 0.57 ft Critical Depth 0.61 ft Channel Slope 0.00500 ft/ft Critical Slope 0.00407 ft/ft Worksheet for Circular Pipe - 1 2/26/2019 1:15:59 PM Bentley Systems, Inc. Haestad Methods Solution CenterBentley FlowMaster V8i (SELECTseries 1) [08.11.01.03] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 2of2Page WWHM2012 PROJECT REPORT 20190226-Filterra Calcs 2/26/2019 12:45:55 PM Page 2 General Model Information Project Name:20190226-Filterra Calcs Site Name: Site Address: City: Report Date:2/26/2019 Gage:Seatac Data Start:1948/10/01 Data End:2009/09/30 Timestep:15 Minute Precip Scale:1.000 Version Date:2017/07/05 Version:4.2.13 POC Thresholds Low Flow Threshold for POC1:50 Percent of the 2 Year High Flow Threshold for POC1:50 Year Low Flow Threshold for POC2:50 Percent of the 2 Year High Flow Threshold for POC2:50 Year 20190226-Filterra Calcs 2/26/2019 12:45:55 PM Page 3 Landuse Basin Data Predeveloped Land Use South Basin Bypass:No GroundWater:No Pervious Land Use acre A B, Forest, Flat 1.15 Pervious Total 1.15 Impervious Land Use acre Impervious Total 0 Basin Total 1.15 Element Flows To: Surface Interflow Groundwater 20190226-Filterra Calcs 2/26/2019 12:45:55 PM Page 4 North Basin Bypass:No GroundWater:No Pervious Land Use acre A B, Forest, Flat 0.7 Pervious Total 0.7 Impervious Land Use acre Impervious Total 0 Basin Total 0.7 Element Flows To: Surface Interflow Groundwater 20190226-Filterra Calcs 2/26/2019 12:45:55 PM Page 5 Mitigated Land Use South Basin Bypass:No GroundWater:No Pervious Land Use acre Pervious Total 0 Impervious Land Use acre ROADS FLAT 1.15 Impervious Total 1.15 Basin Total 1.15 Element Flows To: Surface Interflow Groundwater Filterra South Filterra South 20190226-Filterra Calcs 2/26/2019 12:45:55 PM Page 6 North Basin Bypass:No GroundWater:No Pervious Land Use acre Pervious Total 0 Impervious Land Use acre ROADS FLAT 0.7 Impervious Total 0.7 Basin Total 0.7 Element Flows To: Surface Interflow Groundwater Filterra North Filterra North 20190226-Filterra Calcs 2/26/2019 12:45:55 PM Page 7 Routing Elements Predeveloped Routing 20190226-Filterra Calcs 2/26/2019 12:45:55 PM Page 8 Mitigated Routing Filterra South Bottom Length:16.00 ft. Bottom Width:8.00 ft. Depth:0.75 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 Filtration On Hydraulic conductivity:24.82 Depth of filter medium:1.8 Total Volume Infiltrated (ac-ft.):163.891 Total Volume Through Riser (ac-ft.):15.53 Total Volume Through Facility (ac-ft.):179.421 Percent Infiltrated:91.34 Total Precip Applied to Facility:0 Total Evap From Facility:0 Discharge Structure Riser Height:0.7 ft. Riser Diameter:100 in. Element Flows To: Outlet 1 Outlet 2 Sand Filter Hydraulic Table Stage(feet)Area(ac.)Volume(ac-ft.)Discharge(cfs)Infilt(cfs) 0.0000 0.002 0.000 0.000 0.000 0.0083 0.002 0.000 0.000 0.073 0.0167 0.002 0.000 0.000 0.074 0.0250 0.002 0.000 0.000 0.074 0.0333 0.002 0.000 0.000 0.074 0.0417 0.002 0.000 0.000 0.075 0.0500 0.002 0.000 0.000 0.075 0.0583 0.002 0.000 0.000 0.075 0.0667 0.002 0.000 0.000 0.076 0.0750 0.002 0.000 0.000 0.076 0.0833 0.002 0.000 0.000 0.076 0.0917 0.002 0.000 0.000 0.077 0.1000 0.002 0.000 0.000 0.077 0.1083 0.002 0.000 0.000 0.078 0.1167 0.002 0.000 0.000 0.078 0.1250 0.002 0.000 0.000 0.078 0.1333 0.002 0.000 0.000 0.079 0.1417 0.002 0.000 0.000 0.079 0.1500 0.002 0.000 0.000 0.079 0.1583 0.002 0.000 0.000 0.080 0.1667 0.002 0.000 0.000 0.080 0.1750 0.002 0.000 0.000 0.080 0.1833 0.002 0.000 0.000 0.081 0.1917 0.002 0.000 0.000 0.081 0.2000 0.002 0.000 0.000 0.081 0.2083 0.002 0.000 0.000 0.082 0.2167 0.002 0.000 0.000 0.082 0.2250 0.002 0.000 0.000 0.082 20190226-Filterra Calcs 2/26/2019 12:45:55 PM Page 9 0.2333 0.002 0.000 0.000 0.083 0.2417 0.002 0.000 0.000 0.083 0.2500 0.002 0.000 0.000 0.083 0.2583 0.002 0.000 0.000 0.084 0.2667 0.002 0.000 0.000 0.084 0.2750 0.002 0.000 0.000 0.084 0.2833 0.002 0.000 0.000 0.085 0.2917 0.002 0.000 0.000 0.085 0.3000 0.002 0.000 0.000 0.085 0.3083 0.002 0.000 0.000 0.086 0.3167 0.002 0.000 0.000 0.086 0.3250 0.002 0.001 0.000 0.086 0.3333 0.002 0.001 0.000 0.087 0.3417 0.002 0.001 0.000 0.087 0.3500 0.002 0.001 0.000 0.087 0.3583 0.002 0.001 0.000 0.088 0.3667 0.002 0.001 0.000 0.088 0.3750 0.002 0.001 0.000 0.088 0.3833 0.002 0.001 0.000 0.089 0.3917 0.002 0.001 0.000 0.089 0.4000 0.002 0.001 0.000 0.089 0.4083 0.002 0.001 0.000 0.090 0.4167 0.002 0.001 0.000 0.090 0.4250 0.002 0.001 0.000 0.090 0.4333 0.002 0.001 0.000 0.091 0.4417 0.002 0.001 0.000 0.091 0.4500 0.002 0.001 0.000 0.091 0.4583 0.002 0.001 0.000 0.092 0.4667 0.002 0.001 0.000 0.092 0.4750 0.002 0.001 0.000 0.092 0.4833 0.002 0.001 0.000 0.093 0.4917 0.002 0.001 0.000 0.093 0.5000 0.002 0.001 0.000 0.094 0.5083 0.002 0.001 0.000 0.094 0.5167 0.002 0.001 0.000 0.094 0.5250 0.002 0.001 0.000 0.095 0.5333 0.002 0.001 0.000 0.095 0.5417 0.002 0.001 0.000 0.095 0.5500 0.002 0.001 0.000 0.096 0.5583 0.002 0.001 0.000 0.096 0.5667 0.002 0.001 0.000 0.096 0.5750 0.002 0.001 0.000 0.097 0.5833 0.002 0.001 0.000 0.097 0.5917 0.002 0.001 0.000 0.097 0.6000 0.002 0.001 0.000 0.098 0.6083 0.002 0.001 0.000 0.098 0.6167 0.002 0.001 0.000 0.098 0.6250 0.002 0.001 0.000 0.099 0.6333 0.002 0.001 0.000 0.099 0.6417 0.002 0.001 0.000 0.099 0.6500 0.002 0.001 0.000 0.100 0.6583 0.002 0.001 0.000 0.100 0.6667 0.002 0.002 0.000 0.100 0.6750 0.002 0.002 0.000 0.101 0.6833 0.002 0.002 0.000 0.101 0.6917 0.002 0.002 0.000 0.101 0.7000 0.002 0.002 0.000 0.102 0.7083 0.002 0.002 0.067 0.102 20190226-Filterra Calcs 2/26/2019 12:45:55 PM Page 10 0.7167 0.002 0.002 0.190 0.102 0.7250 0.002 0.002 0.349 0.103 0.7333 0.002 0.002 0.538 0.103 0.7417 0.002 0.002 0.752 0.103 0.7500 0.002 0.002 0.989 0.104 0.7583 0.002 0.002 1.246 0.104 20190226-Filterra Calcs 2/26/2019 12:45:55 PM Page 11 Filterra North Bottom Length:13.00 ft. Bottom Width:7.00 ft. Depth:0.75 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 Filtration On Hydraulic conductivity:24.82 Depth of filter medium:1.8 Total Volume Infiltrated (ac-ft.):102.019 Total Volume Through Riser (ac-ft.):6.793 Total Volume Through Facility (ac-ft.):108.812 Percent Infiltrated:93.76 Total Precip Applied to Facility:0 Total Evap From Facility:0 Discharge Structure Riser Height:0.7 ft. Riser Diameter:100 in. Element Flows To: Outlet 1 Outlet 2 Sand Filter Hydraulic Table Stage(feet)Area(ac.)Volume(ac-ft.)Discharge(cfs)Infilt(cfs) 0.0000 0.002089 0.000000 0.000 0.000 0.0083 0.002089 0.000017 0.000 0.052 0.0167 0.002089 0.000035 0.000 0.052 0.0250 0.002089 0.000052 0.000 0.053 0.0333 0.002089 0.000070 0.000 0.053 0.0417 0.002089 0.000087 0.000 0.053 0.0500 0.002089 0.000104 0.000 0.053 0.0583 0.002089 0.000122 0.000 0.054 0.0667 0.002089 0.000139 0.000 0.054 0.0750 0.002089 0.000157 0.000 0.054 0.0833 0.002089 0.000174 0.000 0.054 0.0917 0.002089 0.000191 0.000 0.054 0.1000 0.002089 0.000209 0.000 0.055 0.1083 0.002089 0.000226 0.000 0.055 0.1167 0.002089 0.000244 0.000 0.055 0.1250 0.002089 0.000261 0.000 0.055 0.1333 0.002089 0.000279 0.000 0.056 0.1417 0.002089 0.000296 0.000 0.056 0.1500 0.002089 0.000313 0.000 0.056 0.1583 0.002089 0.000331 0.000 0.056 0.1667 0.002089 0.000348 0.000 0.057 0.1750 0.002089 0.000366 0.000 0.057 0.1833 0.002089 0.000383 0.000 0.057 0.1917 0.002089 0.000400 0.000 0.057 0.2000 0.002089 0.000418 0.000 0.058 0.2083 0.002089 0.000435 0.000 0.058 0.2167 0.002089 0.000453 0.000 0.058 0.2250 0.002089 0.000470 0.000 0.058 0.2333 0.002089 0.000487 0.000 0.059 0.2417 0.002089 0.000505 0.000 0.059 20190226-Filterra Calcs 2/26/2019 12:45:55 PM Page 12 0.2500 0.002089 0.000522 0.000 0.059 0.2583 0.002089 0.000540 0.000 0.059 0.2667 0.002089 0.000557 0.000 0.060 0.2750 0.002089 0.000574 0.000 0.060 0.2833 0.002089 0.000592 0.000 0.060 0.2917 0.002089 0.000609 0.000 0.060 0.3000 0.002089 0.000627 0.000 0.061 0.3083 0.002089 0.000644 0.000 0.061 0.3167 0.002089 0.000662 0.000 0.061 0.3250 0.002089 0.000679 0.000 0.061 0.3333 0.002089 0.000696 0.000 0.062 0.3417 0.002089 0.000714 0.000 0.062 0.3500 0.002089 0.000731 0.000 0.062 0.3583 0.002089 0.000749 0.000 0.062 0.3667 0.002089 0.000766 0.000 0.062 0.3750 0.002089 0.000783 0.000 0.063 0.3833 0.002089 0.000801 0.000 0.063 0.3917 0.002089 0.000818 0.000 0.063 0.4000 0.002089 0.000836 0.000 0.063 0.4083 0.002089 0.000853 0.000 0.064 0.4167 0.002089 0.000870 0.000 0.064 0.4250 0.002089 0.000888 0.000 0.064 0.4333 0.002089 0.000905 0.000 0.064 0.4417 0.002089 0.000923 0.000 0.065 0.4500 0.002089 0.000940 0.000 0.065 0.4583 0.002089 0.000957 0.000 0.065 0.4667 0.002089 0.000975 0.000 0.065 0.4750 0.002089 0.000992 0.000 0.066 0.4833 0.002089 0.001010 0.000 0.066 0.4917 0.002089 0.001027 0.000 0.066 0.5000 0.002089 0.001045 0.000 0.066 0.5083 0.002089 0.001062 0.000 0.067 0.5167 0.002089 0.001079 0.000 0.067 0.5250 0.002089 0.001097 0.000 0.067 0.5333 0.002089 0.001114 0.000 0.067 0.5417 0.002089 0.001132 0.000 0.068 0.5500 0.002089 0.001149 0.000 0.068 0.5583 0.002089 0.001166 0.000 0.068 0.5667 0.002089 0.001184 0.000 0.068 0.5750 0.002089 0.001201 0.000 0.069 0.5833 0.002089 0.001219 0.000 0.069 0.5917 0.002089 0.001236 0.000 0.069 0.6000 0.002089 0.001253 0.000 0.069 0.6083 0.002089 0.001271 0.000 0.070 0.6167 0.002089 0.001288 0.000 0.070 0.6250 0.002089 0.001306 0.000 0.070 0.6333 0.002089 0.001323 0.000 0.070 0.6417 0.002089 0.001340 0.000 0.070 0.6500 0.002089 0.001358 0.000 0.071 0.6583 0.002089 0.001375 0.000 0.071 0.6667 0.002089 0.001393 0.000 0.071 0.6750 0.002089 0.001410 0.000 0.071 0.6833 0.002089 0.001428 0.000 0.072 0.6917 0.002089 0.001445 0.000 0.072 0.7000 0.002089 0.001462 0.000 0.072 0.7083 0.002089 0.001480 0.067 0.072 0.7167 0.002089 0.001497 0.190 0.073 0.7250 0.002089 0.001515 0.349 0.073 20190226-Filterra Calcs 2/26/2019 12:45:55 PM Page 13 0.7333 0.002089 0.001532 0.538 0.073 0.7417 0.002089 0.001549 0.752 0.073 0.7500 0.002089 0.001567 0.989 0.074 0.7583 0.002089 0.001584 1.246 0.074 20190226-Filterra Calcs 2/26/2019 12:45:55 PM Page 14 Analysis Results POC 1 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area:1.15 Total Impervious Area:0 Mitigated Landuse Totals for POC #1 Total Pervious Area:0 Total Impervious Area:1.15 Flow Frequency Method:Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.000976 5 year 0.001477 10 year 0.001885 25 year 0.002497 50 year 0.003031 100 year 0.003637 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.331888 5 year 0.44707 10 year 0.527576 25 year 0.634266 50 year 0.717428 100 year 0.803805 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1949 0.001 0.463 1950 0.002 0.510 1951 0.002 0.251 1952 0.001 0.214 1953 0.001 0.238 1954 0.001 0.254 1955 0.001 0.300 1956 0.001 0.295 1957 0.001 0.348 1958 0.001 0.259 20190226-Filterra Calcs 2/26/2019 12:46:34 PM Page 15 1959 0.001 0.266 1960 0.001 0.260 1961 0.001 0.284 1962 0.001 0.233 1963 0.001 0.269 1964 0.001 0.261 1965 0.001 0.364 1966 0.001 0.208 1967 0.001 0.433 1968 0.001 0.503 1969 0.001 0.321 1970 0.001 0.304 1971 0.001 0.383 1972 0.005 0.401 1973 0.001 0.200 1974 0.001 0.339 1975 0.001 0.408 1976 0.001 0.240 1977 0.001 0.270 1978 0.001 0.349 1979 0.001 0.521 1980 0.001 0.460 1981 0.001 0.354 1982 0.001 0.543 1983 0.001 0.424 1984 0.001 0.229 1985 0.001 0.354 1986 0.001 0.293 1987 0.001 0.509 1988 0.001 0.266 1989 0.001 0.319 1990 0.001 0.681 1991 0.001 0.520 1992 0.001 0.226 1993 0.001 0.180 1994 0.001 0.207 1995 0.001 0.303 1996 0.006 0.333 1997 0.001 0.316 1998 0.001 0.322 1999 0.001 0.765 2000 0.001 0.330 2001 0.001 0.371 2002 0.001 0.454 2003 0.001 0.325 2004 0.001 0.705 2005 0.001 0.270 2006 0.001 0.225 2007 0.010 0.656 2008 0.001 0.505 2009 0.001 0.466 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.0096 0.7653 2 0.0064 0.7052 3 0.0048 0.6806 20190226-Filterra Calcs 2/26/2019 12:46:34 PM Page 16 4 0.0017 0.6557 5 0.0017 0.5431 6 0.0015 0.5206 7 0.0015 0.5202 8 0.0009 0.5099 9 0.0009 0.5087 10 0.0009 0.5052 11 0.0009 0.5031 12 0.0009 0.4659 13 0.0009 0.4635 14 0.0009 0.4604 15 0.0009 0.4535 16 0.0009 0.4326 17 0.0009 0.4243 18 0.0009 0.4085 19 0.0009 0.4014 20 0.0009 0.3828 21 0.0009 0.3712 22 0.0009 0.3635 23 0.0009 0.3544 24 0.0009 0.3543 25 0.0009 0.3487 26 0.0009 0.3484 27 0.0009 0.3391 28 0.0009 0.3334 29 0.0009 0.3296 30 0.0009 0.3248 31 0.0009 0.3216 32 0.0009 0.3211 33 0.0009 0.3191 34 0.0009 0.3162 35 0.0009 0.3042 36 0.0009 0.3030 37 0.0009 0.3002 38 0.0009 0.2952 39 0.0009 0.2935 40 0.0009 0.2837 41 0.0009 0.2705 42 0.0009 0.2702 43 0.0009 0.2694 44 0.0009 0.2661 45 0.0009 0.2658 46 0.0009 0.2609 47 0.0009 0.2597 48 0.0009 0.2589 49 0.0009 0.2541 50 0.0009 0.2514 51 0.0009 0.2397 52 0.0009 0.2384 53 0.0009 0.2328 54 0.0009 0.2289 55 0.0009 0.2262 56 0.0009 0.2246 57 0.0009 0.2138 58 0.0008 0.2079 59 0.0008 0.2066 60 0.0007 0.1996 61 0.0007 0.1799 20190226-Filterra Calcs 2/26/2019 12:46:34 PM Page 17 20190226-Filterra Calcs 2/26/2019 12:46:34 PM Page 18 Duration Flows Flow(cfs)Predev Mit Percentage Pass/Fail 0.0005 3031 11499 379 Fail 0.0005 2714 11488 423 Fail 0.0005 2391 11479 480 Fail 0.0006 2141 11471 535 Fail 0.0006 1915 11467 598 Fail 0.0006 1687 11464 679 Fail 0.0006 1475 11462 777 Fail 0.0007 1330 11456 861 Fail 0.0007 1173 11449 976 Fail 0.0007 1009 11449 1134 Fail 0.0007 842 11447 1359 Fail 0.0008 674 11443 1697 Fail 0.0008 552 11439 2072 Fail 0.0008 446 11434 2563 Fail 0.0008 354 11428 3228 Fail 0.0009 250 11424 4569 Fail 0.0009 135 11422 8460 Fail 0.0009 36 11422 31727 Fail 0.0010 26 11419 43919 Fail 0.0010 26 11415 43903 Fail 0.0010 26 11400 43846 Fail 0.0010 26 11396 43830 Fail 0.0011 25 11396 45584 Fail 0.0011 25 11392 45568 Fail 0.0011 24 11390 47458 Fail 0.0011 23 11383 49491 Fail 0.0012 23 11379 49473 Fail 0.0012 23 11379 49473 Fail 0.0012 22 11379 51722 Fail 0.0012 22 11377 51713 Fail 0.0013 22 11370 51681 Fail 0.0013 21 11362 54104 Fail 0.0013 21 11353 54061 Fail 0.0013 21 11351 54052 Fail 0.0014 21 11345 54023 Fail 0.0014 19 11340 59684 Fail 0.0014 19 11336 59663 Fail 0.0014 18 11330 62944 Fail 0.0015 18 11323 62905 Fail 0.0015 18 11317 62872 Fail 0.0015 16 11317 70731 Fail 0.0015 16 11313 70706 Fail 0.0016 16 11308 70675 Fail 0.0016 16 11306 70662 Fail 0.0016 16 11298 70612 Fail 0.0016 15 11291 75273 Fail 0.0017 15 11289 75260 Fail 0.0017 15 11287 75246 Fail 0.0017 14 11280 80571 Fail 0.0017 13 11280 86769 Fail 0.0018 13 11278 86753 Fail 0.0018 13 11276 86738 Fail 0.0018 13 11272 86707 Fail 0.0018 13 11265 86653 Fail 20190226-Filterra Calcs 2/26/2019 12:46:34 PM Page 19 0.0019 13 11261 86623 Fail 0.0019 12 11259 93825 Fail 0.0019 12 11253 93775 Fail 0.0020 12 11248 93733 Fail 0.0020 11 11246 102236 Fail 0.0020 11 11240 102181 Fail 0.0020 11 11240 102181 Fail 0.0021 11 11233 102118 Fail 0.0021 10 11229 112290 Fail 0.0021 10 11229 112290 Fail 0.0021 9 11227 124744 Fail 0.0022 9 11221 124677 Fail 0.0022 9 11214 124600 Fail 0.0022 9 11212 124577 Fail 0.0022 9 11212 124577 Fail 0.0023 8 11203 140037 Fail 0.0023 8 11199 139987 Fail 0.0023 8 11188 139850 Fail 0.0023 8 11180 139750 Fail 0.0024 8 11178 139725 Fail 0.0024 8 11174 139675 Fail 0.0024 8 11171 139637 Fail 0.0024 8 11165 139562 Fail 0.0025 8 11163 139537 Fail 0.0025 8 11156 139450 Fail 0.0025 8 11150 139375 Fail 0.0025 8 11148 139350 Fail 0.0026 8 11139 139237 Fail 0.0026 8 11137 139212 Fail 0.0026 8 11137 139212 Fail 0.0026 8 11133 139162 Fail 0.0027 8 11124 139050 Fail 0.0027 8 11120 139000 Fail 0.0027 8 11118 138975 Fail 0.0027 8 11109 138862 Fail 0.0028 8 11105 138812 Fail 0.0028 8 11103 138787 Fail 0.0028 8 11101 138762 Fail 0.0029 8 11097 138712 Fail 0.0029 8 11088 138600 Fail 0.0029 8 11086 138575 Fail 0.0029 8 11084 138550 Fail 0.0030 8 11082 138525 Fail 0.0030 8 11073 138412 Fail 0.0030 8 11069 138362 Fail 0.0030 8 11062 138275 Fail The development has an increase in flow durations from 1/2 Predeveloped 2 year flow to the 2 year flow or more than a 10% increase from the 2 year to the 50 year flow. The development has an increase in flow durations for more than 50% of the flows for the range of the duration analysis. 20190226-Filterra Calcs 2/26/2019 12:46:34 PM Page 20 Water Quality Water Quality BMP Flow and Volume for POC #1 On-line facility volume:0 acre-feet On-line facility target flow:0 cfs. Adjusted for 15 min:0 cfs. Off-line facility target flow:0 cfs. Adjusted for 15 min:0 cfs. 20190226-Filterra Calcs 2/26/2019 12:46:34 PM Page 21 LID Report 20190226-Filterra Calcs 2/26/2019 12:47:11 PM Page 22 POC 2 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #2 Total Pervious Area:0.7 Total Impervious Area:0 Mitigated Landuse Totals for POC #2 Total Pervious Area:0 Total Impervious Area:0.7 Flow Frequency Method:Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #2 Return Period Flow(cfs) 2 year 0.000594 5 year 0.000899 10 year 0.001147 25 year 0.00152 50 year 0.001845 100 year 0.002214 Flow Frequency Return Periods for Mitigated. POC #2 Return Period Flow(cfs) 2 year 0.19061 5 year 0.261269 10 year 0.311314 25 year 0.378319 50 year 0.431013 100 year 0.486124 Annual Peaks Annual Peaks for Predeveloped and Mitigated. POC #2 Year Predeveloped Mitigated 1949 0.000 0.272 1950 0.001 0.300 1951 0.001 0.143 1952 0.001 0.120 1953 0.001 0.134 1954 0.001 0.144 1955 0.001 0.173 1956 0.001 0.169 1957 0.001 0.202 1958 0.001 0.148 1959 0.001 0.151 20190226-Filterra Calcs 2/26/2019 12:47:37 PM Page 23 1960 0.001 0.148 1961 0.001 0.162 1962 0.001 0.132 1963 0.001 0.153 1964 0.001 0.148 1965 0.001 0.211 1966 0.001 0.116 1967 0.001 0.253 1968 0.001 0.295 1969 0.001 0.185 1970 0.001 0.175 1971 0.001 0.223 1972 0.003 0.234 1973 0.001 0.104 1974 0.001 0.196 1975 0.001 0.239 1976 0.001 0.136 1977 0.000 0.154 1978 0.001 0.202 1979 0.000 0.306 1980 0.001 0.269 1981 0.001 0.205 1982 0.001 0.320 1983 0.001 0.248 1984 0.001 0.129 1985 0.001 0.205 1986 0.001 0.168 1987 0.001 0.299 1988 0.001 0.152 1989 0.001 0.172 1990 0.001 0.404 1991 0.001 0.306 1992 0.001 0.127 1993 0.000 0.099 1994 0.001 0.115 1995 0.001 0.174 1996 0.004 0.192 1997 0.001 0.182 1998 0.001 0.185 1999 0.001 0.455 2000 0.001 0.191 2001 0.001 0.216 2002 0.001 0.266 2003 0.001 0.187 2004 0.001 0.420 2005 0.001 0.154 2006 0.001 0.126 2007 0.006 0.389 2008 0.001 0.298 2009 0.001 0.274 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #2 Rank Predeveloped Mitigated 1 0.0058 0.4546 2 0.0039 0.4200 3 0.0029 0.4037 4 0.0011 0.3890 20190226-Filterra Calcs 2/26/2019 12:47:37 PM Page 24 5 0.0010 0.3202 6 0.0009 0.3064 7 0.0009 0.3062 8 0.0006 0.3004 9 0.0006 0.2993 10 0.0006 0.2977 11 0.0006 0.2954 12 0.0006 0.2736 13 0.0006 0.2722 14 0.0006 0.2692 15 0.0006 0.2659 16 0.0006 0.2529 17 0.0006 0.2477 18 0.0006 0.2389 19 0.0006 0.2343 20 0.0006 0.2230 21 0.0006 0.2157 22 0.0006 0.2106 23 0.0006 0.2054 24 0.0006 0.2054 25 0.0006 0.2019 26 0.0006 0.2015 27 0.0006 0.1959 28 0.0006 0.1919 29 0.0006 0.1906 30 0.0006 0.1871 31 0.0006 0.1852 32 0.0006 0.1848 33 0.0006 0.1821 34 0.0005 0.1753 35 0.0005 0.1743 36 0.0005 0.1727 37 0.0005 0.1721 38 0.0005 0.1691 39 0.0005 0.1678 40 0.0005 0.1615 41 0.0005 0.1540 42 0.0005 0.1538 43 0.0005 0.1534 44 0.0005 0.1518 45 0.0005 0.1511 46 0.0005 0.1481 47 0.0005 0.1480 48 0.0005 0.1476 49 0.0005 0.1443 50 0.0005 0.1431 51 0.0005 0.1363 52 0.0005 0.1343 53 0.0005 0.1321 54 0.0005 0.1293 55 0.0005 0.1271 56 0.0005 0.1257 57 0.0005 0.1197 58 0.0005 0.1162 59 0.0005 0.1151 60 0.0004 0.1043 61 0.0004 0.0986 20190226-Filterra Calcs 2/26/2019 12:47:37 PM Page 25 20190226-Filterra Calcs 2/26/2019 12:47:37 PM Page 26 Duration Flows Flow(cfs)Predev Mit Percentage Pass/Fail 0.0003 3033 7751 255 Fail 0.0003 2725 7751 284 Fail 0.0003 2393 7751 323 Fail 0.0003 2152 7751 360 Fail 0.0004 1915 7751 404 Fail 0.0004 1687 7751 459 Fail 0.0004 1487 7751 521 Fail 0.0004 1330 7751 582 Fail 0.0004 1173 7751 660 Fail 0.0004 1011 7751 766 Fail 0.0005 841 7751 921 Fail 0.0005 671 7747 1154 Fail 0.0005 554 7745 1398 Fail 0.0005 446 7738 1734 Fail 0.0005 355 7736 2179 Fail 0.0005 253 7734 3056 Fail 0.0005 129 7732 5993 Fail 0.0006 36 7730 21472 Fail 0.0006 26 7726 29715 Fail 0.0006 26 7723 29703 Fail 0.0006 26 7721 29696 Fail 0.0006 26 7717 29680 Fail 0.0006 25 7715 30860 Fail 0.0007 25 7713 30851 Fail 0.0007 24 7713 32137 Fail 0.0007 23 7706 33504 Fail 0.0007 23 7702 33486 Fail 0.0007 23 7700 33478 Fail 0.0007 22 7698 34990 Fail 0.0008 22 7696 34981 Fail 0.0008 22 7694 34972 Fail 0.0008 21 7689 36614 Fail 0.0008 21 7687 36604 Fail 0.0008 21 7685 36595 Fail 0.0008 21 7683 36585 Fail 0.0008 19 7681 40426 Fail 0.0009 19 7679 40415 Fail 0.0009 18 7672 42622 Fail 0.0009 18 7672 42622 Fail 0.0009 18 7672 42622 Fail 0.0009 16 7670 47937 Fail 0.0009 16 7666 47912 Fail 0.0010 16 7666 47912 Fail 0.0010 16 7661 47881 Fail 0.0010 16 7657 47856 Fail 0.0010 15 7655 51033 Fail 0.0010 15 7655 51033 Fail 0.0010 15 7653 51020 Fail 0.0010 14 7653 54664 Fail 0.0011 13 7651 58853 Fail 0.0011 13 7644 58800 Fail 0.0011 13 7642 58784 Fail 0.0011 13 7642 58784 Fail 0.0011 13 7638 58753 Fail 20190226-Filterra Calcs 2/26/2019 12:47:37 PM Page 27 0.0011 13 7638 58753 Fail 0.0012 12 7636 63633 Fail 0.0012 12 7632 63600 Fail 0.0012 12 7629 63575 Fail 0.0012 11 7627 69336 Fail 0.0012 11 7621 69281 Fail 0.0012 11 7619 69263 Fail 0.0013 11 7614 69218 Fail 0.0013 10 7610 76100 Fail 0.0013 10 7608 76080 Fail 0.0013 9 7604 84488 Fail 0.0013 9 7602 84466 Fail 0.0013 9 7599 84433 Fail 0.0013 9 7599 84433 Fail 0.0014 9 7597 84411 Fail 0.0014 8 7597 94962 Fail 0.0014 8 7597 94962 Fail 0.0014 8 7593 94912 Fail 0.0014 8 7591 94887 Fail 0.0014 8 7587 94837 Fail 0.0015 8 7584 94800 Fail 0.0015 8 7582 94775 Fail 0.0015 8 7582 94775 Fail 0.0015 8 7578 94725 Fail 0.0015 8 7578 94725 Fail 0.0015 8 7572 94650 Fail 0.0015 8 7572 94650 Fail 0.0016 8 7569 94612 Fail 0.0016 8 7565 94562 Fail 0.0016 8 7563 94537 Fail 0.0016 8 7561 94512 Fail 0.0016 8 7559 94487 Fail 0.0016 8 7557 94462 Fail 0.0017 8 7555 94437 Fail 0.0017 8 7550 94375 Fail 0.0017 8 7548 94350 Fail 0.0017 8 7546 94325 Fail 0.0017 8 7546 94325 Fail 0.0017 8 7544 94300 Fail 0.0018 8 7542 94275 Fail 0.0018 8 7540 94250 Fail 0.0018 8 7533 94162 Fail 0.0018 8 7533 94162 Fail 0.0018 8 7533 94162 Fail 0.0018 8 7533 94162 Fail 0.0018 8 7531 94137 Fail The development has an increase in flow durations from 1/2 Predeveloped 2 year flow to the 2 year flow or more than a 10% increase from the 2 year to the 50 year flow. The development has an increase in flow durations for more than 50% of the flows for the range of the duration analysis. 20190226-Filterra Calcs 2/26/2019 12:47:37 PM Page 28 Water Quality Water Quality BMP Flow and Volume for POC #2 On-line facility volume:0 acre-feet On-line facility target flow:0 cfs. Adjusted for 15 min:0 cfs. Off-line facility target flow:0 cfs. Adjusted for 15 min:0 cfs. 20190226-Filterra Calcs 2/26/2019 12:47:37 PM Page 29 LID Report 20190226-Filterra Calcs 2/26/2019 12:47:38 PM Page 30 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. 20190226-Filterra Calcs 2/26/2019 12:47:38 PM Page 31 Appendix Predeveloped Schematic 20190226-Filterra Calcs 2/26/2019 12:47:39 PM Page 32 Mitigated Schematic 20190226-Filterra Calcs 2/26/2019 12:47:40 PM Page 33 Predeveloped UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END 2009 09 30 RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 UNIT SYSTEM 1 END GLOBAL FILES <File> <Un#> <-----------File Name------------------------------>*** <-ID-> *** WDM 26 20190226-Filterra Calcs.wdm MESSU 25 Pre20190226-Filterra Calcs.MES 27 Pre20190226-Filterra Calcs.L61 28 Pre20190226-Filterra Calcs.L62 30 POC20190226-Filterra Calcs1.dat 31 POC20190226-Filterra Calcs2.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 1 COPY 501 COPY 502 DISPLY 1 DISPLY 2 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 South Basin MAX 1 2 30 9 2 North Basin MAX 1 2 31 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 502 1 1 END TIMESERIES END COPY GENER OPCODE # # OPCD *** END OPCODE PARM # # K *** END PARM END GENER PERLND GEN-INFO <PLS ><-------Name------->NBLKS Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 1 A/B, Forest, Flat 1 1 1 1 27 0 END GEN-INFO *** Section PWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC *** 1 0 0 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO 20190226-Filterra Calcs 2/26/2019 12:47:40 PM Page 34 <PLS > ***************** Print-flags ***************************** PIVL PYR # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC ********* 1 0 0 4 0 0 0 0 0 0 0 0 0 1 9 END PRINT-INFO PWAT-PARM1 <PLS > PWATER variable monthly parameter value flags *** # - # CSNO RTOP UZFG VCS VUZ VNN VIFW VIRC VLE INFC HWT *** 1 0 0 0 0 0 0 0 0 0 0 0 END PWAT-PARM1 PWAT-PARM2 <PLS > PWATER input info: Part 2 *** # - # ***FOREST LZSN INFILT LSUR SLSUR KVARY AGWRC 1 0 5 2 400 0.05 0.3 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 1 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 1 0.2 0.5 0.35 0 0.7 0.7 END PWAT-PARM4 PWAT-STATE1 <PLS > *** Initial conditions at start of simulation ran from 1990 to end of 1992 (pat 1-11-95) RUN 21 *** # - # *** CEPS SURS UZS IFWS LZS AGWS GWVS 1 0 0 0 0 3 1 0 END PWAT-STATE1 END PERLND IMPLND GEN-INFO <PLS ><-------Name-------> Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* END PRINT-INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** END IWAT-PARM1 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN END IWAT-PARM3 20190226-Filterra Calcs 2/26/2019 12:47:40 PM Page 35 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** South Basin*** PERLND 1 1.15 COPY 501 12 PERLND 1 1.15 COPY 501 13 North Basin*** PERLND 1 0.7 COPY 502 12 PERLND 1 0.7 COPY 502 13 ******Routing****** END SCHEMATIC NETWORK <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** COPY 501 OUTPUT MEAN 1 1 48.4 DISPLY 1 INPUT TIMSER 1 COPY 502 OUTPUT MEAN 1 1 48.4 DISPLY 2 INPUT TIMSER 1 <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** END NETWORK RCHRES GEN-INFO RCHRES Name Nexits Unit Systems Printer *** # - #<------------------><---> User T-series Engl Metr LKFG *** in out *** END GEN-INFO *** Section RCHRES*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG *** END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ******************* PIVL PYR # - # HYDR ADCA CONS HEAT SED GQL OXRX NUTR PLNK PHCB PIVL PYR ********* END PRINT-INFO HYDR-PARM1 RCHRES Flags for each HYDR Section *** # - # VC A1 A2 A3 ODFVFG for each *** ODGTFG for each FUNCT for each FG FG FG FG possible exit *** possible exit possible exit * * * * * * * * * * * * * * *** END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** <------><--------><--------><--------><--------><--------><--------> *** END HYDR-PARM2 HYDR-INIT RCHRES Initial conditions for each HYDR section *** # - # *** VOL Initial value of COLIND Initial value of OUTDGT *** ac-ft for each possible exit for each possible exit <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> END HYDR-INIT END RCHRES SPEC-ACTIONS 20190226-Filterra Calcs 2/26/2019 12:47:40 PM Page 36 END SPEC-ACTIONS FTABLES END FTABLES EXT SOURCES <-Volume-> <Member> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # tem strg<-factor->strg <Name> # # <Name> # # *** WDM 2 PREC ENGL 1 PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1 IMPLND 1 999 EXTNL PREC WDM 1 EVAP ENGL 0.76 PERLND 1 999 EXTNL PETINP WDM 1 EVAP ENGL 0.76 IMPLND 1 999 EXTNL PETINP END EXT SOURCES EXT TARGETS <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Volume-> <Member> Tsys Tgap Amd *** <Name> # <Name> # #<-factor->strg <Name> # <Name> tem strg strg*** COPY 501 OUTPUT MEAN 1 1 48.4 WDM 501 FLOW ENGL REPL COPY 502 OUTPUT MEAN 1 1 48.4 WDM 502 FLOW ENGL REPL END EXT TARGETS MASS-LINK <Volume> <-Grp> <-Member-><--Mult--> <Target> <-Grp> <-Member->*** <Name> <Name> # #<-factor-> <Name> <Name> # #*** MASS-LINK 12 PERLND PWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 12 MASS-LINK 13 PERLND PWATER IFWO 0.083333 COPY INPUT MEAN END MASS-LINK 13 END MASS-LINK END RUN 20190226-Filterra Calcs 2/26/2019 12:47:40 PM Page 37 Mitigated UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END 2009 09 30 RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 UNIT SYSTEM 1 END GLOBAL FILES <File> <Un#> <-----------File Name------------------------------>*** <-ID-> *** WDM 26 20190226-Filterra Calcs.wdm MESSU 25 Mit20190226-Filterra Calcs.MES 27 Mit20190226-Filterra Calcs.L61 28 Mit20190226-Filterra Calcs.L62 30 POC20190226-Filterra Calcs1.dat 31 POC20190226-Filterra Calcs2.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 IMPLND 1 RCHRES 1 RCHRES 2 COPY 1 COPY 501 COPY 2 COPY 502 DISPLY 1 DISPLY 2 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 Filterra South MAX 1 2 30 9 2 Filterra North MAX 1 2 31 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 2 1 1 502 1 1 END TIMESERIES END COPY GENER OPCODE # # OPCD *** END OPCODE PARM # # K *** END PARM END GENER PERLND GEN-INFO <PLS ><-------Name------->NBLKS Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** END GEN-INFO *** Section PWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC *** 20190226-Filterra Calcs 2/26/2019 12:47:40 PM Page 38 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ***************************** PIVL PYR # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC ********* END PRINT-INFO PWAT-PARM1 <PLS > PWATER variable monthly parameter value flags *** # - # CSNO RTOP UZFG VCS VUZ VNN VIFW VIRC VLE INFC HWT *** END PWAT-PARM1 PWAT-PARM2 <PLS > PWATER input info: Part 2 *** # - # ***FOREST LZSN INFILT LSUR SLSUR KVARY AGWRC END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** END PWAT-PARM4 PWAT-STATE1 <PLS > *** Initial conditions at start of simulation ran from 1990 to end of 1992 (pat 1-11-95) RUN 21 *** # - # *** CEPS SURS UZS IFWS LZS AGWS GWVS END PWAT-STATE1 END PERLND IMPLND GEN-INFO <PLS ><-------Name-------> Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 1 ROADS/FLAT 1 1 1 27 0 END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** 1 0 0 1 0 0 0 END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* 1 0 0 4 0 0 0 1 9 END PRINT-INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** 1 0 0 0 0 0 END IWAT-PARM1 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC 1 400 0.01 0.1 0.1 END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN 20190226-Filterra Calcs 2/26/2019 12:47:40 PM Page 39 1 0 0 END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 1 0 0 END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** South Basin*** IMPLND 1 1.15 RCHRES 1 5 North Basin*** IMPLND 1 0.7 RCHRES 2 5 ******Routing****** IMPLND 1 1.15 COPY 1 15 IMPLND 1 0.7 COPY 2 15 RCHRES 1 1 COPY 501 17 RCHRES 2 1 COPY 502 17 END SCHEMATIC NETWORK <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** COPY 501 OUTPUT MEAN 1 1 48.4 DISPLY 1 INPUT TIMSER 1 COPY 502 OUTPUT MEAN 1 1 48.4 DISPLY 2 INPUT TIMSER 1 <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** END NETWORK RCHRES GEN-INFO RCHRES Name Nexits Unit Systems Printer *** # - #<------------------><---> User T-series Engl Metr LKFG *** in out *** 1 Filterra South 2 1 1 1 28 0 1 2 Filterra North 2 1 1 1 28 0 1 END GEN-INFO *** Section RCHRES*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG *** 1 1 0 0 0 0 0 0 0 0 0 2 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ******************* PIVL PYR # - # HYDR ADCA CONS HEAT SED GQL OXRX NUTR PLNK PHCB PIVL PYR ********* 1 4 0 0 0 0 0 0 0 0 0 1 9 2 4 0 0 0 0 0 0 0 0 0 1 9 END PRINT-INFO HYDR-PARM1 RCHRES Flags for each HYDR Section *** # - # VC A1 A2 A3 ODFVFG for each *** ODGTFG for each FUNCT for each FG FG FG FG possible exit *** possible exit possible exit * * * * * * * * * * * * * * *** 1 0 1 0 0 4 5 0 0 0 0 0 0 0 0 2 2 2 2 2 2 0 1 0 0 4 5 0 0 0 0 0 0 0 0 2 2 2 2 2 END HYDR-PARM1 20190226-Filterra Calcs 2/26/2019 12:47:40 PM Page 40 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** <------><--------><--------><--------><--------><--------><--------> *** 1 1 0.01 0.0 0.0 0.5 0.0 2 2 0.01 0.0 0.0 0.5 0.0 END HYDR-PARM2 HYDR-INIT RCHRES Initial conditions for each HYDR section *** # - # *** VOL Initial value of COLIND Initial value of OUTDGT *** ac-ft for each possible exit for each possible exit <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> 1 0 4.0 5.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2 0 4.0 5.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 END HYDR-INIT END RCHRES SPEC-ACTIONS END SPEC-ACTIONS FTABLES FTABLE 1 91 5 Depth Area Volume Outflow1 Outflow2 Velocity Travel Time*** (ft) (acres) (acre-ft) (cfs) (cfs) (ft/sec) (Minutes)*** 0.000000 0.002938 0.000000 0.000000 0.000000 0.008333 0.002938 0.000024 0.000000 0.073881 0.016667 0.002938 0.000049 0.000000 0.074222 0.025000 0.002938 0.000073 0.000000 0.074562 0.033333 0.002938 0.000098 0.000000 0.074903 0.041667 0.002938 0.000122 0.000000 0.075243 0.050000 0.002938 0.000147 0.000000 0.075584 0.058333 0.002938 0.000171 0.000000 0.075924 0.066667 0.002938 0.000196 0.000000 0.076264 0.075000 0.002938 0.000220 0.000000 0.076605 0.083333 0.002938 0.000245 0.000000 0.076945 0.091667 0.002938 0.000269 0.000000 0.077286 0.100000 0.002938 0.000294 0.000000 0.077626 0.108333 0.002938 0.000318 0.000000 0.077967 0.116667 0.002938 0.000343 0.000000 0.078307 0.125000 0.002938 0.000367 0.000000 0.078648 0.133333 0.002938 0.000392 0.000000 0.078988 0.141667 0.002938 0.000416 0.000000 0.079329 0.150000 0.002938 0.000441 0.000000 0.079669 0.158333 0.002938 0.000465 0.000000 0.080010 0.166667 0.002938 0.000490 0.000000 0.080350 0.175000 0.002938 0.000514 0.000000 0.080691 0.183333 0.002938 0.000539 0.000000 0.081031 0.191667 0.002938 0.000563 0.000000 0.081371 0.200000 0.002938 0.000588 0.000000 0.081712 0.208333 0.002938 0.000612 0.000000 0.082052 0.216667 0.002938 0.000637 0.000000 0.082393 0.225000 0.002938 0.000661 0.000000 0.082733 0.233333 0.002938 0.000686 0.000000 0.083074 0.241667 0.002938 0.000710 0.000000 0.083414 0.250000 0.002938 0.000735 0.000000 0.083755 0.258333 0.002938 0.000759 0.000000 0.084095 0.266667 0.002938 0.000784 0.000000 0.084436 0.275000 0.002938 0.000808 0.000000 0.084776 0.283333 0.002938 0.000833 0.000000 0.085117 0.291667 0.002938 0.000857 0.000000 0.085457 0.300000 0.002938 0.000882 0.000000 0.085798 0.308333 0.002938 0.000906 0.000000 0.086138 0.316667 0.002938 0.000931 0.000000 0.086478 0.325000 0.002938 0.000955 0.000000 0.086819 0.333333 0.002938 0.000979 0.000000 0.087159 0.341667 0.002938 0.001004 0.000000 0.087500 0.350000 0.002938 0.001028 0.000000 0.087840 0.358333 0.002938 0.001053 0.000000 0.088181 0.366667 0.002938 0.001077 0.000000 0.088521 0.375000 0.002938 0.001102 0.000000 0.088862 20190226-Filterra Calcs 2/26/2019 12:47:41 PM Page 41 0.383333 0.002938 0.001126 0.000000 0.089202 0.391667 0.002938 0.001151 0.000000 0.089543 0.400000 0.002938 0.001175 0.000000 0.089883 0.408333 0.002938 0.001200 0.000000 0.090224 0.416667 0.002938 0.001224 0.000000 0.090564 0.425000 0.002938 0.001249 0.000000 0.090905 0.433333 0.002938 0.001273 0.000000 0.091245 0.441667 0.002938 0.001298 0.000000 0.091585 0.450000 0.002938 0.001322 0.000000 0.091926 0.458333 0.002938 0.001347 0.000000 0.092266 0.466667 0.002938 0.001371 0.000000 0.092607 0.475000 0.002938 0.001396 0.000000 0.092947 0.483333 0.002938 0.001420 0.000000 0.093288 0.491667 0.002938 0.001445 0.000000 0.093628 0.500000 0.002938 0.001469 0.000000 0.093969 0.508333 0.002938 0.001494 0.000000 0.094309 0.516667 0.002938 0.001518 0.000000 0.094650 0.525000 0.002938 0.001543 0.000000 0.094990 0.533333 0.002938 0.001567 0.000000 0.095331 0.541667 0.002938 0.001592 0.000000 0.095671 0.550000 0.002938 0.001616 0.000000 0.096012 0.558333 0.002938 0.001641 0.000000 0.096352 0.566667 0.002938 0.001665 0.000000 0.096692 0.575000 0.002938 0.001690 0.000000 0.097033 0.583333 0.002938 0.001714 0.000000 0.097373 0.591667 0.002938 0.001739 0.000000 0.097714 0.600000 0.002938 0.001763 0.000000 0.098054 0.608333 0.002938 0.001788 0.000000 0.098395 0.616667 0.002938 0.001812 0.000000 0.098735 0.625000 0.002938 0.001837 0.000000 0.099076 0.633333 0.002938 0.001861 0.000000 0.099416 0.641667 0.002938 0.001886 0.000000 0.099757 0.650000 0.002938 0.001910 0.000000 0.100097 0.658333 0.002938 0.001934 0.000000 0.100438 0.666667 0.002938 0.001959 0.000000 0.100778 0.675000 0.002938 0.001983 0.000000 0.101119 0.683333 0.002938 0.002008 0.000000 0.101459 0.691667 0.002938 0.002032 0.000000 0.101799 0.700000 0.002938 0.002057 0.000000 0.102140 0.708333 0.002938 0.002081 0.067333 0.102480 0.716667 0.002938 0.002106 0.190433 0.102821 0.725000 0.002938 0.002130 0.349825 0.103161 0.733333 0.002938 0.002155 0.538557 0.103502 0.741667 0.002938 0.002179 0.752610 0.103842 0.750000 0.002938 0.002204 0.989273 0.104183 END FTABLE 1 FTABLE 2 91 5 Depth Area Volume Outflow1 Outflow2 Velocity Travel Time*** (ft) (acres) (acre-ft) (cfs) (cfs) (ft/sec) (Minutes)*** 0.000000 0.002089 0.000000 0.000000 0.000000 0.008333 0.002089 0.000017 0.000000 0.052525 0.016667 0.002089 0.000035 0.000000 0.052767 0.025000 0.002089 0.000052 0.000000 0.053009 0.033333 0.002089 0.000070 0.000000 0.053251 0.041667 0.002089 0.000087 0.000000 0.053493 0.050000 0.002089 0.000104 0.000000 0.053735 0.058333 0.002089 0.000122 0.000000 0.053977 0.066667 0.002089 0.000139 0.000000 0.054219 0.075000 0.002089 0.000157 0.000000 0.054461 0.083333 0.002089 0.000174 0.000000 0.054703 0.091667 0.002089 0.000191 0.000000 0.054945 0.100000 0.002089 0.000209 0.000000 0.055187 0.108333 0.002089 0.000226 0.000000 0.055430 0.116667 0.002089 0.000244 0.000000 0.055672 0.125000 0.002089 0.000261 0.000000 0.055914 0.133333 0.002089 0.000279 0.000000 0.056156 0.141667 0.002089 0.000296 0.000000 0.056398 0.150000 0.002089 0.000313 0.000000 0.056640 0.158333 0.002089 0.000331 0.000000 0.056882 20190226-Filterra Calcs 2/26/2019 12:47:41 PM Page 42 0.166667 0.002089 0.000348 0.000000 0.057124 0.175000 0.002089 0.000366 0.000000 0.057366 0.183333 0.002089 0.000383 0.000000 0.057608 0.191667 0.002089 0.000400 0.000000 0.057850 0.200000 0.002089 0.000418 0.000000 0.058092 0.208333 0.002089 0.000435 0.000000 0.058334 0.216667 0.002089 0.000453 0.000000 0.058576 0.225000 0.002089 0.000470 0.000000 0.058818 0.233333 0.002089 0.000487 0.000000 0.059060 0.241667 0.002089 0.000505 0.000000 0.059302 0.250000 0.002089 0.000522 0.000000 0.059544 0.258333 0.002089 0.000540 0.000000 0.059786 0.266667 0.002089 0.000557 0.000000 0.060028 0.275000 0.002089 0.000574 0.000000 0.060271 0.283333 0.002089 0.000592 0.000000 0.060513 0.291667 0.002089 0.000609 0.000000 0.060755 0.300000 0.002089 0.000627 0.000000 0.060997 0.308333 0.002089 0.000644 0.000000 0.061239 0.316667 0.002089 0.000662 0.000000 0.061481 0.325000 0.002089 0.000679 0.000000 0.061723 0.333333 0.002089 0.000696 0.000000 0.061965 0.341667 0.002089 0.000714 0.000000 0.062207 0.350000 0.002089 0.000731 0.000000 0.062449 0.358333 0.002089 0.000749 0.000000 0.062691 0.366667 0.002089 0.000766 0.000000 0.062933 0.375000 0.002089 0.000783 0.000000 0.063175 0.383333 0.002089 0.000801 0.000000 0.063417 0.391667 0.002089 0.000818 0.000000 0.063659 0.400000 0.002089 0.000836 0.000000 0.063901 0.408333 0.002089 0.000853 0.000000 0.064143 0.416667 0.002089 0.000870 0.000000 0.064385 0.425000 0.002089 0.000888 0.000000 0.064627 0.433333 0.002089 0.000905 0.000000 0.064869 0.441667 0.002089 0.000923 0.000000 0.065112 0.450000 0.002089 0.000940 0.000000 0.065354 0.458333 0.002089 0.000957 0.000000 0.065596 0.466667 0.002089 0.000975 0.000000 0.065838 0.475000 0.002089 0.000992 0.000000 0.066080 0.483333 0.002089 0.001010 0.000000 0.066322 0.491667 0.002089 0.001027 0.000000 0.066564 0.500000 0.002089 0.001045 0.000000 0.066806 0.508333 0.002089 0.001062 0.000000 0.067048 0.516667 0.002089 0.001079 0.000000 0.067290 0.525000 0.002089 0.001097 0.000000 0.067532 0.533333 0.002089 0.001114 0.000000 0.067774 0.541667 0.002089 0.001132 0.000000 0.068016 0.550000 0.002089 0.001149 0.000000 0.068258 0.558333 0.002089 0.001166 0.000000 0.068500 0.566667 0.002089 0.001184 0.000000 0.068742 0.575000 0.002089 0.001201 0.000000 0.068984 0.583333 0.002089 0.001219 0.000000 0.069226 0.591667 0.002089 0.001236 0.000000 0.069468 0.600000 0.002089 0.001253 0.000000 0.069710 0.608333 0.002089 0.001271 0.000000 0.069953 0.616667 0.002089 0.001288 0.000000 0.070195 0.625000 0.002089 0.001306 0.000000 0.070437 0.633333 0.002089 0.001323 0.000000 0.070679 0.641667 0.002089 0.001340 0.000000 0.070921 0.650000 0.002089 0.001358 0.000000 0.071163 0.658333 0.002089 0.001375 0.000000 0.071405 0.666667 0.002089 0.001393 0.000000 0.071647 0.675000 0.002089 0.001410 0.000000 0.071889 0.683333 0.002089 0.001428 0.000000 0.072131 0.691667 0.002089 0.001445 0.000000 0.072373 0.700000 0.002089 0.001462 0.000000 0.072615 0.708333 0.002089 0.001480 0.067333 0.072857 0.716667 0.002089 0.001497 0.190433 0.073099 0.725000 0.002089 0.001515 0.349825 0.073341 0.733333 0.002089 0.001532 0.538557 0.073583 0.741667 0.002089 0.001549 0.752610 0.073825 20190226-Filterra Calcs 2/26/2019 12:47:41 PM Page 43 0.750000 0.002089 0.001567 0.989273 0.074067 END FTABLE 2 END FTABLES EXT SOURCES <-Volume-> <Member> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # tem strg<-factor->strg <Name> # # <Name> # # *** WDM 2 PREC ENGL 1 PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1 IMPLND 1 999 EXTNL PREC WDM 1 EVAP ENGL 0.76 PERLND 1 999 EXTNL PETINP WDM 1 EVAP ENGL 0.76 IMPLND 1 999 EXTNL PETINP END EXT SOURCES EXT TARGETS <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Volume-> <Member> Tsys Tgap Amd *** <Name> # <Name> # #<-factor->strg <Name> # <Name> tem strg strg*** RCHRES 1 HYDR RO 1 1 1 WDM 1000 FLOW ENGL REPL RCHRES 1 HYDR O 1 1 1 WDM 1001 FLOW ENGL REPL RCHRES 1 HYDR O 2 1 1 WDM 1002 FLOW ENGL REPL RCHRES 1 HYDR STAGE 1 1 1 WDM 1003 STAG ENGL REPL COPY 1 OUTPUT MEAN 1 1 48.4 WDM 701 FLOW ENGL REPL COPY 501 OUTPUT MEAN 1 1 48.4 WDM 801 FLOW ENGL REPL RCHRES 2 HYDR RO 1 1 1 WDM 1004 FLOW ENGL REPL RCHRES 2 HYDR O 1 1 1 WDM 1005 FLOW ENGL REPL RCHRES 2 HYDR O 2 1 1 WDM 1006 FLOW ENGL REPL RCHRES 2 HYDR STAGE 1 1 1 WDM 1007 STAG ENGL REPL COPY 2 OUTPUT MEAN 1 1 48.4 WDM 702 FLOW ENGL REPL COPY 502 OUTPUT MEAN 1 1 48.4 WDM 802 FLOW ENGL REPL END EXT TARGETS MASS-LINK <Volume> <-Grp> <-Member-><--Mult--> <Target> <-Grp> <-Member->*** <Name> <Name> # #<-factor-> <Name> <Name> # #*** MASS-LINK 5 IMPLND IWATER SURO 0.083333 RCHRES INFLOW IVOL END MASS-LINK 5 MASS-LINK 15 IMPLND IWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 15 MASS-LINK 17 RCHRES OFLOW OVOL 1 COPY INPUT MEAN END MASS-LINK 17 END MASS-LINK END RUN 20190226-Filterra Calcs 2/26/2019 12:47:41 PM Page 44 Predeveloped HSPF Message File 20190226-Filterra Calcs 2/26/2019 12:47:41 PM Page 45 Mitigated HSPF Message File ERROR/WARNING ID: 341 6 DATE/TIME: 2003/10/20 12:15 RCHRES: 1 The volume of water in this reach/mixed reservoir is greater than the value in the "volume" column of the last row of RCHTAB(). To continue the simulation the table has been extrapolated, based on information contained in the last two rows. This will usually result in some loss of accuracy. If depth is being calculated it will also cause an error condition. Relevant data are: NROWS V1 V2 VOL 91 9.4917E+01 96.006 96.998 ERROR/WARNING ID: 341 5 DATE/TIME: 2003/10/20 12:15 RCHRES: 1 Calculation of relative depth, using Newton's method of successive approximations, converged to an invalid value (not in range 0.0 to 1.0). Probably ftable was extrapolated. If extrapolation was small, no problem. Remedy; extend ftable. Relevant data are: A B C RDEP1 RDEP2 COUNT 0.0000E+00 255.96 -489.14 1.9110 1.9110E+00 2 20190226-Filterra Calcs 2/26/2019 12:47:41 PM Page 46 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. 2005-2019; 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 Technical Information Report 2940, 2960, 2980, and 2990 East Valley Road Renton, WA 98057 2190112.10 Appendix E Exhibits E-1 .................... Operations & Maintenance Guide COMPTON LUMBER RENTON Operations & Maintenance Guide Page  King County Drainage Maintenance Standards for Commercial and Multifamily Drainage Facilities Type I Catch Basin (See Figure B-1 in Appendix) Definition: An underground concrete water receiving inlet, rectangular in shape (approximately 3’ X 2’ X 4’ deep) with a slotted iron grate on top to inlet water or a solid rectangular cover. Water may also enter/exit through cul- verts visible in the side walls of basin. Invert refers to the lowest point of a pipe where it enters or exits a catch basin. Defect Number & Defect: A-1 General—Trash & Debris (Including Sediment) Blocking Water From Entering Basin: Trash or debris covering any portion of the catch basin grate or blocking inlet grate to basin. Maintenance Necessary to Bring to Standard: Remove all trash, debris and sediment from in front of the catch basin inlet. Refer to the disposal guidelines in Appendix A for instructions on disposal of trash, debris and sediment. A-2 General—Trash & Debris (Including Sediment): Trash, debris and sediment (in the basin) that exceeds one-third the depth from the bottom of the basin to invert of the lowest pipe into or out of the basin. This is the most common maintenance requirement. Maintenance Necessary to Bring to Standard: Remove all trash, debris and sediment from the catch basin. Refer to the disposal guidelines in Appendix A for instructions on disposal of trash, debris and sediment. A-3 General—Trash & Debris (Including Sediment): Trash, debris and sediment in any inlet or outlet pipe blocking more than one-third of its height. Maintenance Necessary to Bring to Standard: Remove all trash, debris and sediment from inlet and outlet pipes. Refer to the disposal guidelines in Appendix A for instructions on disposal of trash, debris and sediment. A-4 Structural—Structural Damage to Frame and/or Top Slab: Top concrete slab has holes larger than 2 square inches or cracks wider than 1/4 inch (intent is to make sure all material is running into the basin through the grate). Maintenance Necessary to Bring to Standard: Repair top slab so that it is free of holes and cracks. A-5 Structural—Frame not sitting flush on top slab, i.e., separation of more than 3/4 inch of the frame from the top slab. Maintenance Necessary to Bring to Standard: Repair so that frame is sitting flush on top slab. A-6 Structural—Cracks in Basin Walls/Bottom: Cracks wider than 1/2 inch, any evidence of soil particles or water entering catch basin through cracks, or maintenance person judges that structure is unsound. Maintenance Necessary to Bring to Standard: Replace or repair basin to design standards. A-7 Structural—Cracks in Basin Around Inletting Culverts: Cracks wider than 1/2 inch at the joint of any inlet/outlet pipe or any evidence of soil particles or water entering catch basin through cracks. Maintenance Necessary to Bring to Standard: Replace or repair basin to design standards. A-8 Structural—Settlement/Misalignment: Basin has settled more than 1 inch or has rotated more than 2 inches out of alignment. Maintenance Necessary to Bring to Standard: Replace or repair basin to design standards. A. King County Drainage Maintenance Standards for Commercial and Multifamily Drainage Facilities Page  A-9 General—Pollution: Presence of any pollutants (including paint, auto fluids, grease and food waste) or flammable materials. Maintenance Necessary to Bring to Standard: Remove contaminants so that none are present. Contact the Waste Characterization Program at 206-296-4633 to determine how to dispose of pollutants and flammable material. Also, contact Water and Land Resources at 206-296-1900 for a water quality site consultation to eliminate the source of the pollution. A-10 Catch Basin Cover—Not in Place: Cover is missing or only partially in place. Any open catch basin requires maintenance. Maintenance Necessary to Bring to Standard: Replace missing cover or repair catch basin cover so that it is closed. A-11 Metal Grates—Safety Hazard: Grate with opening wider than 7/8 inch. Maintenance Necessary to Bring to Standard: Repair grate openings so that they meet design standards. A-12 Metal Grates—Trash & Debris: Trash and debris that is blocking grate surface. Maintenance Necessary to Bring to Standard: Remove all trash and debris from grate. Refer to the disposal guidelines in Appendix A for instructions on disposal of trash, debris and sediment. A-13 Metal Grates—Damaged or Missing: Grate is missing or has broken members. Maintenance Necessary to Bring to Standard: Repair or replace grate so that it is in place and meets design standards. Type II Catch Basin (See Figure B-2 in Appendix) Definition: A round concrete underground basin (4’-8’ in diameter; 6’ deep or deeper); may contain a Flow Restrictor Oil Pollution (FROP) control device or a T-section with a specifically sized orifice(s) to control release rates or a spill control device. These basins are also required when larger diameter culverts are used. Defect Number & Defect: B-1 General—Trash & Debris (Including Sediment): Trash, debris and sediment covering the catch basin grate or is blocking any portion of inlet to basin. Maintenance Necessary to Bring to Standard: Remove trash, debris and sediment so that none is located immediately in front of catch basin inlet. Refer to the disposal guidelines in Appendix A for instructions on disposal of trash, debris and sediment. B-2 General—Trash & Debris (Including Sediment): Trash, debris and sediment (in the basin) that exceeds one-third the depth from the bottom of the basin to invert of the lowest pipe into or out of the basin. This is the most common maintenance requirement. Maintenance Necessary to Bring to Standard: Remove all trash, debris and sediment from the catch basin. Refer to the disposal guidelines in Appendix A for instructions on disposal of trash, debris and sediment. B. Page  King County Drainage Maintenance Standards for Commercial and Multifamily Drainage Facilities B-3 General—Trash & Debris (Including Sediment): Trash, debris and sediment in any inlet or outlet pipe blocking more than one-third of its height. Maintenance Necessary to Bring to Standard: Remove all trash, debris and sediment from inlet and outlet pipes. Refer to the disposal guidelines in Appendix A for instructions on disposal of trash, debris and sediment. B-4 Structural—Structural Damage to Frame and/or Top Slab: Top slab has holes larger than 2 square inches or cracks wider than 1/4 inch (intent is to make sure all material is running into the basin). Maintenance Necessary to Bring to Standard: Repair top slab so that it is free of holes and cracks. B-5 Structural—Frame Not Sitting Flush on Top Slab, i.e., separation of more than 3/4 inch of the frame from the top slab. Maintenance Necessary to Bring to Standard: Repair so that frame is sitting flush on top slab. B-6 Structural—Cracks in Basin Walls/Bottom: Cracks wider than 1/2 inch and longer than 3 feet, any evidence of soil particles or water entering catch basin through cracks, or maintenance person judges that structure is unsound. Maintenance Necessary to Bring to Standard: Replace or repair basin to design standards. B-7 Structural—Cracks in Pipe Joints: Cracks wider than 1/2 inch and longer than 1 foot at the joint of any inlet/outlet pipe or any evidence of soil particles or water entering catch basin through cracks. Maintenance Necessary to Bring to Standard: Replace or repair basin to design standards. B-8 Structural—Settlement/Misalignment: Basin has settled more than 1 inch or has rotated more than 2 inches out of alignment. Maintenance Necessary to Bring to Standard: Replace or repair basin to design standards. B-9 General—Pollution: Presence of any chemical pollutants or flammable materials. Maintenance Necessary to Bring to Standard: Remove contaminants so that none are present. Contact the Waste Characterization program at 206-296-4633 to determine how to dispose of pollutants and flammable material. Also, contact Water and Land Resources at 206-296-1900 for a water quality site consultation to eliminate the source of the pollution. B-10 Catch Basin Cover—Not in Place: Cover is missing or only partially in place. Any open catch basin requires maintenance. Maintenance Necessary to Bring to Standard: Repair or replace catch basin cover so that it is closed. B-11 Metal Grates—Safety Hazard: Grate with opening wider than 7/8 inch. Maintenance Necessary to Bring to Standard: Repair grate openings so that they meet design standards. B-12 Metal Grates—Trash & Debris: Trash and debris that is blocking grate surface. Maintenance Necessary to Bring to Standard: Remove all trash and debris from grate. Refer to the disposal guidelines in Appendix A for instructions on disposal of trash, debris and sediment. King County Drainage Maintenance Standards for Commercial and Multifamily Drainage Facilities Page  B-13 Metal Grates—Damaged or Missing: Grate is missing or has broken members. Maintenance Necessary to Bring to Standard: Repair or replace grate so that it is in place and meets design standards. B-14 Ladder—Rungs Unsafe: Maintenance person judges that ladder is unsafe due to missing rungs, misalignment, rust, or cracks. Maintenance Necessary to Bring to Standard: Repair ladder so that it meets design standards and allows maintenance person safe access. Flow Restrictor (See Figure B-3 in Appendix) Definition: A facility such as a Flow Restrictor Oil Pollution (FROP) control device with a specifically sized orifice(s) to control release rates or a spill control device. Usually located in a Type II Catch Basin/Control Manhole; designated as “CS,” “CS/CB,” or “CS/MH” on your site plan. There may be a vertical culvert at the outlet (“T”) with additional elbow orifice inlets (secondary orifice). Defect Number & Defect: C-1 General—Trash & Debris (Includes Sediment): Distance between debris buildup and bottom of orifice plate is less that 1-1/2 feet (18 inches). Similar to B-2. Maintenance Necessary to Bring to Standard: Remove all trash and debris. Refer to the disposal guidelines in Appendix A for instructions on disposal of trash, debris and sediment. C-2 General—Structural Damage: Structure is not securely attached to manhole wall (outlet pipe structure should support at least 1,000 pounds of up or down pressure); and/or structure is not in upright position (allow up to 10% from plumb). (Structure is usually secured with banding material.) Maintenance Necessary to Bring to Standard: Repair structure to be securely attached to wall so that outlet pipe supports at least 1,000 pounds of up or down pressure; and ensure outlet pipe is in correct position. C-3 General—Structural Damage: Connections to outlet pipe are not watertight and show signs of rust or deteriorated grout. Maintenance Necessary to Bring to Standard: Repair connections to outlet pipe so that they are watertight; repair or replace structure so that it works as designed. C-4 General—Structural Damage: Any holes—other than designed holes—in the structure. Maintenance Necessary to Bring to Standard: Repair holes so that structure has no holes other than designed holes. C-5 Cleanout Gate—Damaged or Missing: Cleanout gate is not watertight or is missing. Maintenance Necessary to Bring to Standard: Repair or replace gate so that it is watertight and works as designed. C-6 Cleanout Gate—Will Not Open or Opens with Difficulty: Gate cannot be moved up and down by one person. Maintenance Necessary to Bring to Standard: Repair gate so that it moves up and down easily and is watertight. C. King County Drainage Maintenance Standards for Commercial and Multifamily Drainage Facilities Page  D-3 General—Missing Bars: Bars are missing, or entire barrier is missing. Maintenance Necessary to Bring to Standard: Repair or replace bars according to design standards. D-4 General—Bars are loose and rust is causing 50% deterioration to any part of barrier. Maintenance Necessary to Bring to Standard: Repair or replace barrier according to design standards. Energy Dissipater/Dispersion Trench Definition: A rock pad constructed at inlets/outlets to prevent erosion (Energy Dissipater), or a catch basin used to slow fast flowing runoff (Energy Dissipater), or a constructed percolation trench to disperse outletting flows over a large area (Dispersion Trench). Catch basins may be a part of the dispersion trench; see Type I or Type II Catch Basins (Items A and B) for maintenance requirements. Defect Number & Defect: E-1 Rock Pad—Missing or Moved Rock: One layer or less of rock exists above native soil in area five square feet or larger, or any exposure of native soil. Maintenance Necessary to Bring to Standard: Replace rocks to design standard. E-2 Energy Dissipater—Needs Replacement: Visible signs of pad erosion, or plugged dispersion trenches. Maintenance Necessary to Bring to Standard: Replace energy dissipater. E-3 Dispersion Trench—Pipe Plugged with Sediment: Accumulated sediment that exceeds 20% of the design depth. Maintenance Necessary to Bring to Standard: Clean/flush pipe so that it matches design. Refer to the disposal guidelines in Appendix A for instructions on disposal of trash, debris and sediment. E-4 Dispersion Trench—Not Discharging Water Properly: Visual evidence of water discharging at concentrated points along trench (normal condition is a “sheet flow” of water along trench). Intent is to prevent erosion damage. Maintenance Necessary to Bring to Standard: Rebuild trench to design standards. E-5 Dispersion Trench—Perforations Plugged: Over 1/2 of perforations in pipe are plugged with debris and sediment. Maintenance Necessary to Bring to Standard: Clean or replace perforated pipe. Refer to the disposal guidelines in Appendix A for instructions on disposal of trash, debris and sediment. E-6 Dispersion Trench—Water Flows Out Top of “Distributor” Catch Basin: Water has been observed flowing out during any storm less than the design storm, or it is causing or appears likely to cause damage. Maintenance Necessary to Bring to Standard: Rebuild facility to design standards. E-7 Dispersion Trench—Receiving Area Oversaturated: Water in receiving area is causing or has potential of causing landslide problems. Maintenance Necessary to Bring to Standard: Ensure that engineer’s evaluation of outlet function and soil stability is satisfactory. E. Filterra Owner’s Manual ® Bioretention Systems ENGINEERED SOLUTIONS www.ContechES.com/filterra | 800-338-1122 3 Table of Contents Introduction ................................................................................4 Activation Overview .....................................................................4 Filterra Plant Selection Overview ...................................................6 Warranty Overview ......................................................................6 Routine Maintenance Guidelines...................................................6 Maintenance Visit Procedure .........................................................9 Appendix 1 – Activation Checklist ...............................................12 Appendix 2 – Planting Requirements for Filterra Systems ................13 Enclosed Local Area Filterra Plant List ® Bioretention Systems ENGINEERED SOLUTIONS www.ContechES.com/filterra | 800-338-11224 Introduction Thank you for your purchase of the Filterra® Bioretention System. Filterra is a specially engineered stormwater treatment system incorporating high performance biofiltration media to remove pollutants from stormwater runoff. The system’s biota (vegetation and soil microorganisms) then further breakdown and absorb captured pollutants. All components of the system work together to provide a sustainable long-term solution for treating stormwater runoff. The Filterra system has been delivered to you with protection in place to resist intrusion of construction related sediment which can contaminate the biofiltration media and result in inadequate system performance. These protection devices are intended as a best practice and cannot fully prevent contamination. It is the purchaser’s responsibility to provide adequate measures to prevent construction related runoff from entering the Filterra system. Included with your purchase is Activation of the Filterra system by the manufacturer as well as a 1-year warranty from delivery of the system and 1-year of routine maintenance (mulch replacement, debris removal, and pruning of vegetation) up to twice during the first year after activation. Design and Installation Each project presents different scopes for the use of Filterra systems. Information and help may be provided to the design engineer during the planning process. Correct Filterra box sizing (by rainfall region) is essential to predict pollutant removal rates for a given area. The engineer shall submit calculations for approval by the local jurisdiction. The contractor is responsible for the correct installation of Filterra units as shown in approved plans. A comprehensive installation manual is available at www.ContechES.com. Activation Overview Activation of the Filterra system is a procedure completed by the manufacturer to place the system into working condition. This involves the following items: • Removal of construction runoff protection devices • Planting of the system’s vegetation • Placement of pretreatment mulch layer using mulch certified for use in Filterra systems. Activation MUST be provided by the manufacturer to ensure proper site conditions are met for Activation, proper installation of the vegetation, and use of pretreatment mulch certified for use in Filterra systems. www.ContechES.com/filterra | 800-338-1122 5 Minimum Requirements The minimum requirements for Filterra Activation are as follows: 1. The site landscaping must be fully stabilized, i.e. full landscaping installed and some grass cover (not just straw and seed) is required to reduce sediment transport. Construction debris and materials should be removed from surrounding area. 2. Final paving must be completed. Final paving ensures that paving materials will not enter and contaminate the Filterra system during the paving process, and that the plant will receive runoff from the drainage area, assisting with plant survival for the Filterra system. 3. Filterra throat opening should be at least 4” in order to ensure adequate capacity for inflow and debris. An Activation Checklist is included on page 12 to ensure proper conditions are met for Contech to perform the Activation services. A charge of $500.00 will be invoiced for each Activation visit requested by Customer where Contech determines that the site does not meet the conditions required for Activation. www.ContechES.com/filterra | 800-338-11226 Filterra Plant Selection Overview A Plant List has been enclosed with this packet highlighting recommended plants for Filterra systems in your area. Keep in mind that plants are subject to availability due to seasonality and required minimum size for the Filterra system. Plants installed in the Filterra system are container plants (max 15 gallon) from nursery stock and will be immature in height and spread at Activation. It is the responsibility of the owner to provide adequate irrigation when necessary to the plant of the Filterra system. The “Planting Requirements for Filterra Systems” document is included as an appendix and discusses proper selection and care of the plants within Filterra systems. Warranty Overview Refer to the Contech Engineered Solutions LLC Stormwater Treatment System LIMITED WARRANTY for further information. The following conditions may void the Filterra system’s warranty and waive the manufacturer provided Activation and Maintenance services: • Unauthorized activation or performance of any of the items listed in the activation overview • Any tampering, modifications or damage to the Filterra system or runoff protection devices • Removal of any Filterra system components • Failure to prevent construction related runoff from entering the Filterra system • Failure to properly store and protect any Filterra components (including media and underdrain stone) that may be shipped separately from the vault Routine Maintenance Guidelines With proper routine maintenance, the biofiltration media within the Filterra system should last as long as traditional bioretention media. Routine maintenance is included by the manufacturer on all Filterra systems for the first year after activation. This includes a maximum of 2 visits to remove debris, replace pretreatment mulch, and prune the vegetation. More information is provided in the Operations and Maintenance Guidelines. Some Filterra systems also contain pretreatment or outlet bays. Depending on site pollutant loading, these bays may require periodic removal of debris, however this is not included in the first year of maintenance, and would likely not be required within the first year of operation. These services, as well as routine maintenance outside of the included first year, can be provided by certified maintenance providers listed on the Contech website. Training can also be provided to other stormwater maintenance or landscape providers. www.ContechES.com/filterra | 800-338-1122 7 Why Maintain? All stormwater treatment systems require maintenance for effective operation. This necessity is often incorporated in your property’s permitting process as a legally binding BMP maintenance agreement. Other reasons to maintain are: • Avoiding legal challenges from your jurisdiction’s maintenance enforcement program. • Prolonging the expected lifespan of your Filterra media. • Avoiding more costly media replacement. • Helping reduce pollutant loads leaving your property. Simple maintenance of the Filterra is required to continue effective pollutant removal from stormwater runoff before discharge into downstream waters. This procedure will also extend the longevity of the living biofilter system. The unit will recycle and accumulate pollutants within the biomass, but is also subjected to other materials entering the inlet. This may include trash, silt and leaves etc. which will be contained above the mulch layer. Too much silt may inhibit the Filterra’s flow rate, which is the reason for site stabilization before activation. Regular replacement of the mulch stops accumulation of such sediment. When to Maintain? Contech includes a 1-year maintenance plan with each system purchase. Annual included maintenance consists of a maximum of two (2) scheduled visits. Additional maintenance may be necessary depending on sediment and trash loading (by Owner or at additional cost). The start of the maintenance plan begins when the system is activated. Maintenance visits are scheduled seasonally; the spring visit aims to clean up after winter loads including salts and sands while the fall visit helps the system by removing excessive leaf litter. It has been found that in regions which receive between 30-50 inches of annual rainfall, (2) two visits are generally required; regions with less rainfall often only require (1) one visit per annum. Varying land uses can affect maintenance frequency; e.g. some fast food restaurants require more frequent trash removal. Contributing drainage areas which are subject to new development wherein the recommended erosion and sediment control measures have not been implemented may require additional maintenance visits. Some sites may be subjected to extreme sediment or trash loads, requiring more frequent maintenance visits. This is the reason for detailed notes of maintenance actions per unit, helping the Supplier and Owner predict future maintenance frequencies, reflecting individual site conditions. Owners must promptly notify the (maintenance) Supplier of any damage to the plant(s), which constitute(s) an integral part of the bioretention technology. Owners should also advise other landscape or maintenance contractors to leave all maintenance to the Supplier (i.e. no pruning or fertilizing) during the first year. www.ContechES.com/filterra | 800-338-11228 Exclusion of Services Clean up due to major contamination such as oils, chemicals, toxic spills, etc. will result in additional costs and are not covered under the Supplier maintenance contract. Should a major contamination event occur the Owner must block off the outlet pipe of the Filterra (where the cleaned runoff drains to, such as drop inlet) and block off the throat of the Filterra. The Supplier should be informed immediately. Maintenance Visit Summary Each maintenance visit consists of the following simple tasks (detailed instructions below). 1. Inspection of Filterra and surrounding area 2. Removal of tree grate and erosion control stones 3. Removal of debris, trash and mulch 4. Mulch replacement 5. Plant health evaluation and pruning or replacement as necessary 6. Clean area around Filterra 7. Complete paperwork Maintenance Tools, Safety Equipment and Supplies Ideal tools include: camera, bucket, shovel, broom, pruners, hoe/rake, and tape measure. Appropriate Personal Protective Equipment (PPE) should be used in accordance with local or company procedures. This may include impervious gloves where the type of trash is unknown, high visibility clothing and barricades when working in close proximity to traffic and also safety hats and shoes. A T-Bar or crowbar should be used for moving the tree grates (up to 170 lbs ea.). Most visits require minor trash removal and a full replacement of mulch. See below for actual number of bagged mulch that is required in each media bay size. Mulch should be a double shredded, hardwood variety. Some visits may require additional Filterra engineered soil media available from the Supplier. Box Length Box Width Filter Surface Area (ft²)Volume at 3” (ft³)# of 2 ft³ Mulch Bags 4 4 4 4 2 6 4 6 6 3 8 4 8 8 4 6 6 9 9 5 8 6 12 12 6 10 6 15 15 8 12 6 18 18 9 13 7 23 23 12 www.ContechES.com/filterra | 800-338-1122 9 1. Inspection of Filterra and surrounding area • Record individual unit before maintenance with photograph (numbered). Record on Maintenance Report (see example in this document) the following: 2. Removal of tree grate and erosion control stones • Remove cast iron grates for access into Filterra box. • Dig out silt (if any) and mulch and remove trash & foreign items. 3. Removal of debris, trash and mulch • After removal of mulch and debris, measure distance from the top of the Filterra engineered media soil to the top of the top slab. Compare the measured distance to the distance shown on the approved Contract Drawings for the system. Add Filterra media (not top soil or other) to bring media up as needed to distance indicated on drawings. Record on Maintenance Report the following: Standing Water yes | no Damage to Box Structure yes | no Damage to Grate yes | no Is Bypass Clear yes | no If yes answered to any of these observations, record with close-up photograph (numbered). Record on Maintenance Report the following: Silt/Clay yes | no Cups/ Bags yes | no Leaves yes | no Buckets Removed ________ Record on Maintenance Report the following: Distance to Top of Top Slab (inches) ________ Inches of Media Added ________ Maintenance Visit Procedure Keep sufficient documentation of maintenance actions to predict location specific maintenance frequencies and needs. An example Maintenance Report is included in this manual. www.ContechES.com/filterra | 800-338-112210 4. Mulch replacement • Add double shredded mulch evenly across the entire unit to a depth of 3”. • Refer to Filterra Mulch Specifications for information on acceptable sources. • Ensure correct repositioning of erosion control stones by the Filterra inlet to allow for entry of trash during a storm event. • Replace Filterra grates correctly using appropriate lifting or moving tools, taking care not to damage the plant. 5. Plant health evaluation and pruning or replacement as necessary • Examine the plant’s health and replace if necessary. • Prune as necessary to encourage growth in the correct directions 6. Clean area around Filterra • Clean area around unit and remove all refuse to be disposed of appropriately. 7. Complete paperwork • Deliver Maintenance Report and photographs to appropriate location (normally Contech during maintenance contract period). • Some jurisdictions may require submission of maintenance reports in accordance with approvals. It is the responsibility of the Owner to comply with local regulations. Record on Maintenance Report the following: Height above Grate _____________________(ft) Width at Widest Point _____________________(ft) Health healthy | unhealthy Damage to Plant yes | no Plant Replaced yes | no www.ContechES.com/filterra | 800-338-1122 11 Maintenance Checklist Filterra Inspection & Maintenance Log Filterra System Size/Model: _____________________________Location: ____________________________________________ Drainage System Failure Problem Conditions to Check Condition that Should Exist Actions Inlet Excessive sediment or trash accumulation. Accumulated sediments or trash impair free flow of water into Filterra. Inlet should be free of obstructions allowing free distributed flow of water into Filterra. Sediments and/or trash should be removed. Mulch Cover Trash and floatable debris accumulation. Excessive trash and/or debris accumulation. Minimal trash or other debris on mulch cover. Trash and debris should be removed and mulch cover raked level. Ensure bark nugget mulch is not used. Mulch Cover “Ponding” of water on mulch cover. “Ponding” in unit could be indicative of clogging due to excessive fine sediment accumulation or spill of petroleum oils. Stormwater should drain freely and evenly through mulch cover. Recommend contact manufacturer and replace mulch as a minimum. Vegetation Plants not growing or in poor condition. Soil/mulch too wet, evidence of spill. Incorrect plant selection. Pest infestation. Vandalism to plants. Plants should be healthy and pest free.Contact manufacturer for advice. Vegetation Plant growth excessive. Plants should be appropriate to the species and location of Filterra. Trim/prune plants in accordance with typical landscaping and safety needs. Structure Structure has visible cracks. Cracks wider than 1/2 inch or evidence of soil particles entering the structure through the cracks. Vault should be repaired. Maintenance is ideally to be performed twice annually. Date Mulch & Debris Removed Depth of Mulch Added Mulch Brand Height of Vegetation Above Grate Vegetation Species Issues with System Comments 1/1/17 5 – 5 gal Buckets 3” Lowe’s Premium Brown Mulch 4’Galaxy Magnolia - Standing water in downstream structure - Removed blockage in downstream structure www.ContechES.com/filterra | 800-338-112212 Appendix 1 – Filterra® Activation Checklist Project Name: ________________________________________Company: ______________________________________________ Site Contact Name: _______________________________________Site Contact Phone/Email: ____________________________ Site Owner/End User Name: _________________________Site Owner/End User Phone/Email: ____________________________ Preferred Activation Date: ___________________________________(provide 2 weeks minimum from date this form is submitted) Site Designation System Size Final Pavement / Top Coat Complete Landscaping Complete / Grass Emerging Construction materials / Piles / Debris Removed Throat Opening Measures 4” Min. Height Plant Species Requested  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No NOTE: A charge of $500.00 will be invoiced for each Activation visit requested by Customer where Contech determines that the site does not meet the conditions required for Activation. ONLY Contech authorized representatives can perform Activation of Filterra systems; unauthorized Activations will void the system warranty and waive manufacturer supplied Activation and 1st Year Maintenance. Attach additional sheets as necessary. Signature Date ENGINEERED SOLUTIONS www.ContechES.com/filterra | 800-338-1122 13 Appendix 2 – Planting Requirements for Filterra® Systems Plant Material Selection • Select plant(s) as specified in the engineering plans and specifications. • Select plant(s) with full root development but not to the point where root bound. • Use local nursery container plants only. Ball and burlapped plants are not permitted. • For precast Filterra systems with a tree grate, plant(s) must not have scaffold limbs at least 14 inches from the crown due to spacing between the top of the mulch and the tree grate. Lower branches can be pruned away provided there are sufficient scaffold branches for tree or shrub development. • For precast Filterra systems with a tree grate, at the time of installation, it is required that plant(s) must be at least 6” above the tree grate opening at installation for all Filterra configurations. This DOES NOT apply to Full Grate Cover designs. • Plant(s) shall not have a mature height greater than 25 feet. • For standard 21” media depth, a 7 – 15 gallon container size shall be used. Media less than 21” (Filterra boxes only) will require smaller container plants. • For precast Filterra systems, plant(s) should have a single trunk at installation, and pruning may be necessary at activation and maintenance for some of the faster growing species, or species known to produce basal sprouts. Plant Installation • During transport protect the plant leaves from wind and excessive jostling. • Prior to removing the plant(s) from the container, ensure the soil moisture is sufficient to maintain the integrity of the root ball. If needed, pre-wet the container plant. • Cut away any roots which are growing out of the container drain holes. Plants with excessive root growth from the drain holes should be rejected. • Plant(s) should be carefully removed from the pot by gently pounding on the sides of the container with the fist to loosen root ball. Then carefully slide out. Do not lift plant(s) by trunk as this can break roots and cause soil to fall off. Extract the root ball in a horizontal position and support it to prevent it from breaking apart. Alternatively the pot can be cut away to minimize root ball disturbance. • Remove any excess soil from above the root flare after removing plant(s) from container. • Excavate a hole with a diameter 4” greater than the root ball, gently place the plant(s). • If plant(s) have any circling roots from being pot bound, gently tease them loose without breaking them. • If root ball has a root mat on the bottom, it should be shaved off with a knife just above the mat line. • Plant the tree/shrub/grass with the top of the root ball 1” above surrounding media to allow for settling. • All plants should have the main stem centered in the tree grate (where applicable) upon completion of installation. • With all trees/shrubs, remove dead, diseased, crossed/rubbing, sharply crotched branches or branches growing excessively long or in wrong direction compared to majority of branches. • To prevent transplant shock (especially if planting takes place in the hot season), it may be necessary to prune some of the foliage to compensate for reduced root uptake capacity. This is accomplished by pruning away some of the smaller secondary branches or a main scaffold branch if there are too many. Too much foliage relative to the root ball can dehydrate and damage the plant. • Plant staking may be required. www.ContechES.com/filterra | 800-338-112214 Mulch Installation • Only mulch that has been meeting Contech Engineered Solutions’ mulch specifications can be used in the Filterra system. • Mulch must be applied to a depth of 3” evenly over the surface of the media. Irrigation Requirements • Each Filterra system must receive adequate irrigation to ensure survival of the living system during periods of drier weather. • Irrigation sources include rainfall runoff from downspouts and/or gutter flow, applied water through the tree grate or in some cases from an irrigation system with emitters installed during construction. • At Activation: Apply about one (cool climates) to two (warm climates) gallons of water per inch of trunk diameter over the root ball. • During Establishment: In common with all plants, each Filterra plant will require more frequent watering during the establishment period. One inch of applied water per week for the first three months is recommended for cooler climates (2 to 3 inches for warmer climates). If the system is receiving rainfall runoff from the drainage area, then irrigation may not be needed. Inspection of the soil moisture content can be evaluated by gently brushing aside the mulch layer and feeling the soil. Be sure to replace the mulch when the assessment is complete. Irrigate as needed**. • Established Plants: Established plants have fully developed root systems and can access the entire water column in the media. Therefore irrigation is less frequent but requires more applied water when performed. For a mature system assume 3.5 inches of available water within the media matrix. Irrigation demand can be estimated as 1” of irrigation demand per week. Therefore if dry periods exceed 3 weeks, irrigation may be required. It is also important to recognize that plants which are exposed to windy areas and reflected heat from paved surfaces may need more frequent irrigation. Long term care should develop a history which is more site specific. ** Five gallons per square yard approximates 1 inch of water Therefore for a 6’ by 6’ Filterra approximately 20-60 gallons of water is needed. To ensure even distribution of water it needs to be evenly sprinkled over the entire surface of the filter bed, with special attention to make sure the root ball is completely wetted. NOTE: if needed, measure the time it takes to fill a five gallon bucket to estimate the applied water flow rate then calculate the time needed to irrigate the Filterra. For example, if the flow rate of the sprinkler is 5 gallons/minute then it would take 12 minutes to irrigate a 6’ by 6’ filter. Notes ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ PDF 1/18 © 2018 Contech Engineered Solutions LLC, a QUIKRETE Company 9025 Centre Pointe Drive, Suite 400 West Chester, OH 45069 info@conteches.com | 800-338-1122 www.ContechES.com ALL RIGHTS RESERVED. PRINTED IN THE USA. NOTHING IN THIS CATALOG SHOULD BE CONSTRUED AS A WARRANTY. APPLICATIONS SUGGESTED HEREIN ARE DESCRIBED ONLY TO HELP READERS MAKE THEIR OWN EVALUATIONS AND DECISIONS, AND ARE NEITHER GUARANTEES NOR WARRANTIES OF SUITABILITY FOR ANY APPLICATION. CONTECH MAKES NO WARRANTY WHATSOEVER, EXPRESS OR IMPLIED, RELATED TO THE APPLICATIONS, MATERIALS, COATINGS, OR PRODUCTS DISCUSSED HEREIN. ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND ALL IMPLIED WARRANTIES OF FITNESS FOR ANY PARTICULAR PURPOSE ARE DISCLAIMED BY CONTECH. SEE CONTECH’S CONDITIONS OF SALE (AVAILABLE AT WWW.CONTECHES.COM/COS) FOR MORE INFORMATION. ® Bioretention Systems ENGINEERED SOLUTIONS Filterra Owner’s Manual ® Bioretention Systems ENGINEERED SOLUTIONS www.ContechES.com/filterra | 800-338-1122 3 Table of Contents Introduction ................................................................................4 Activation Overview .....................................................................4 Filterra Plant Selection Overview ...................................................6 Warranty Overview ......................................................................6 Routine Maintenance Guidelines...................................................6 Maintenance Visit Procedure .........................................................9 Appendix 1 – Activation Checklist ...............................................12 Appendix 2 – Planting Requirements for Filterra Systems ................13 Enclosed Local Area Filterra Plant List ® Bioretention Systems ENGINEERED SOLUTIONS www.ContechES.com/filterra | 800-338-11224 Introduction Thank you for your purchase of the Filterra® Bioretention System. Filterra is a specially engineered stormwater treatment system incorporating high performance biofiltration media to remove pollutants from stormwater runoff. The system’s biota (vegetation and soil microorganisms) then further breakdown and absorb captured pollutants. All components of the system work together to provide a sustainable long-term solution for treating stormwater runoff. The Filterra system has been delivered to you with protection in place to resist intrusion of construction related sediment which can contaminate the biofiltration media and result in inadequate system performance. These protection devices are intended as a best practice and cannot fully prevent contamination. It is the purchaser’s responsibility to provide adequate measures to prevent construction related runoff from entering the Filterra system. Included with your purchase is Activation of the Filterra system by the manufacturer as well as a 1-year warranty from delivery of the system and 1-year of routine maintenance (mulch replacement, debris removal, and pruning of vegetation) up to twice during the first year after activation. Design and Installation Each project presents different scopes for the use of Filterra systems. Information and help may be provided to the design engineer during the planning process. Correct Filterra box sizing (by rainfall region) is essential to predict pollutant removal rates for a given area. The engineer shall submit calculations for approval by the local jurisdiction. The contractor is responsible for the correct installation of Filterra units as shown in approved plans. A comprehensive installation manual is available at www.ContechES.com. Activation Overview Activation of the Filterra system is a procedure completed by the manufacturer to place the system into working condition. This involves the following items: • Removal of construction runoff protection devices • Planting of the system’s vegetation • Placement of pretreatment mulch layer using mulch certified for use in Filterra systems. Activation MUST be provided by the manufacturer to ensure proper site conditions are met for Activation, proper installation of the vegetation, and use of pretreatment mulch certified for use in Filterra systems. www.ContechES.com/filterra | 800-338-1122 5 Minimum Requirements The minimum requirements for Filterra Activation are as follows: 1. The site landscaping must be fully stabilized, i.e. full landscaping installed and some grass cover (not just straw and seed) is required to reduce sediment transport. Construction debris and materials should be removed from surrounding area. 2. Final paving must be completed. Final paving ensures that paving materials will not enter and contaminate the Filterra system during the paving process, and that the plant will receive runoff from the drainage area, assisting with plant survival for the Filterra system. 3. Filterra throat opening should be at least 4” in order to ensure adequate capacity for inflow and debris. An Activation Checklist is included on page 12 to ensure proper conditions are met for Contech to perform the Activation services. A charge of $500.00 will be invoiced for each Activation visit requested by Customer where Contech determines that the site does not meet the conditions required for Activation. www.ContechES.com/filterra | 800-338-11226 Filterra Plant Selection Overview A Plant List has been enclosed with this packet highlighting recommended plants for Filterra systems in your area. Keep in mind that plants are subject to availability due to seasonality and required minimum size for the Filterra system. Plants installed in the Filterra system are container plants (max 15 gallon) from nursery stock and will be immature in height and spread at Activation. It is the responsibility of the owner to provide adequate irrigation when necessary to the plant of the Filterra system. The “Planting Requirements for Filterra Systems” document is included as an appendix and discusses proper selection and care of the plants within Filterra systems. Warranty Overview Refer to the Contech Engineered Solutions LLC Stormwater Treatment System LIMITED WARRANTY for further information. The following conditions may void the Filterra system’s warranty and waive the manufacturer provided Activation and Maintenance services: • Unauthorized activation or performance of any of the items listed in the activation overview • Any tampering, modifications or damage to the Filterra system or runoff protection devices • Removal of any Filterra system components • Failure to prevent construction related runoff from entering the Filterra system • Failure to properly store and protect any Filterra components (including media and underdrain stone) that may be shipped separately from the vault Routine Maintenance Guidelines With proper routine maintenance, the biofiltration media within the Filterra system should last as long as traditional bioretention media. Routine maintenance is included by the manufacturer on all Filterra systems for the first year after activation. This includes a maximum of 2 visits to remove debris, replace pretreatment mulch, and prune the vegetation. More information is provided in the Operations and Maintenance Guidelines. Some Filterra systems also contain pretreatment or outlet bays. Depending on site pollutant loading, these bays may require periodic removal of debris, however this is not included in the first year of maintenance, and would likely not be required within the first year of operation. These services, as well as routine maintenance outside of the included first year, can be provided by certified maintenance providers listed on the Contech website. Training can also be provided to other stormwater maintenance or landscape providers. www.ContechES.com/filterra | 800-338-1122 7 Why Maintain? All stormwater treatment systems require maintenance for effective operation. This necessity is often incorporated in your property’s permitting process as a legally binding BMP maintenance agreement. Other reasons to maintain are: • Avoiding legal challenges from your jurisdiction’s maintenance enforcement program. • Prolonging the expected lifespan of your Filterra media. • Avoiding more costly media replacement. • Helping reduce pollutant loads leaving your property. Simple maintenance of the Filterra is required to continue effective pollutant removal from stormwater runoff before discharge into downstream waters. This procedure will also extend the longevity of the living biofilter system. The unit will recycle and accumulate pollutants within the biomass, but is also subjected to other materials entering the inlet. This may include trash, silt and leaves etc. which will be contained above the mulch layer. Too much silt may inhibit the Filterra’s flow rate, which is the reason for site stabilization before activation. Regular replacement of the mulch stops accumulation of such sediment. When to Maintain? Contech includes a 1-year maintenance plan with each system purchase. Annual included maintenance consists of a maximum of two (2) scheduled visits. Additional maintenance may be necessary depending on sediment and trash loading (by Owner or at additional cost). The start of the maintenance plan begins when the system is activated. Maintenance visits are scheduled seasonally; the spring visit aims to clean up after winter loads including salts and sands while the fall visit helps the system by removing excessive leaf litter. It has been found that in regions which receive between 30-50 inches of annual rainfall, (2) two visits are generally required; regions with less rainfall often only require (1) one visit per annum. Varying land uses can affect maintenance frequency; e.g. some fast food restaurants require more frequent trash removal. Contributing drainage areas which are subject to new development wherein the recommended erosion and sediment control measures have not been implemented may require additional maintenance visits. Some sites may be subjected to extreme sediment or trash loads, requiring more frequent maintenance visits. This is the reason for detailed notes of maintenance actions per unit, helping the Supplier and Owner predict future maintenance frequencies, reflecting individual site conditions. Owners must promptly notify the (maintenance) Supplier of any damage to the plant(s), which constitute(s) an integral part of the bioretention technology. Owners should also advise other landscape or maintenance contractors to leave all maintenance to the Supplier (i.e. no pruning or fertilizing) during the first year. www.ContechES.com/filterra | 800-338-11228 Exclusion of Services Clean up due to major contamination such as oils, chemicals, toxic spills, etc. will result in additional costs and are not covered under the Supplier maintenance contract. Should a major contamination event occur the Owner must block off the outlet pipe of the Filterra (where the cleaned runoff drains to, such as drop inlet) and block off the throat of the Filterra. The Supplier should be informed immediately. Maintenance Visit Summary Each maintenance visit consists of the following simple tasks (detailed instructions below). 1. Inspection of Filterra and surrounding area 2. Removal of tree grate and erosion control stones 3. Removal of debris, trash and mulch 4. Mulch replacement 5. Plant health evaluation and pruning or replacement as necessary 6. Clean area around Filterra 7. Complete paperwork Maintenance Tools, Safety Equipment and Supplies Ideal tools include: camera, bucket, shovel, broom, pruners, hoe/rake, and tape measure. Appropriate Personal Protective Equipment (PPE) should be used in accordance with local or company procedures. This may include impervious gloves where the type of trash is unknown, high visibility clothing and barricades when working in close proximity to traffic and also safety hats and shoes. A T-Bar or crowbar should be used for moving the tree grates (up to 170 lbs ea.). Most visits require minor trash removal and a full replacement of mulch. See below for actual number of bagged mulch that is required in each media bay size. Mulch should be a double shredded, hardwood variety. Some visits may require additional Filterra engineered soil media available from the Supplier. Box Length Box Width Filter Surface Area (ft²)Volume at 3” (ft³)# of 2 ft³ Mulch Bags 4 4 4 4 2 6 4 6 6 3 8 4 8 8 4 6 6 9 9 5 8 6 12 12 6 10 6 15 15 8 12 6 18 18 9 13 7 23 23 12 www.ContechES.com/filterra | 800-338-1122 9 1. Inspection of Filterra and surrounding area • Record individual unit before maintenance with photograph (numbered). Record on Maintenance Report (see example in this document) the following: 2. Removal of tree grate and erosion control stones • Remove cast iron grates for access into Filterra box. • Dig out silt (if any) and mulch and remove trash & foreign items. 3. Removal of debris, trash and mulch • After removal of mulch and debris, measure distance from the top of the Filterra engineered media soil to the top of the top slab. Compare the measured distance to the distance shown on the approved Contract Drawings for the system. Add Filterra media (not top soil or other) to bring media up as needed to distance indicated on drawings. Record on Maintenance Report the following: Standing Water yes | no Damage to Box Structure yes | no Damage to Grate yes | no Is Bypass Clear yes | no If yes answered to any of these observations, record with close-up photograph (numbered). Record on Maintenance Report the following: Silt/Clay yes | no Cups/ Bags yes | no Leaves yes | no Buckets Removed ________ Record on Maintenance Report the following: Distance to Top of Top Slab (inches) ________ Inches of Media Added ________ Maintenance Visit Procedure Keep sufficient documentation of maintenance actions to predict location specific maintenance frequencies and needs. An example Maintenance Report is included in this manual. www.ContechES.com/filterra | 800-338-112210 4. Mulch replacement • Add double shredded mulch evenly across the entire unit to a depth of 3”. • Refer to Filterra Mulch Specifications for information on acceptable sources. • Ensure correct repositioning of erosion control stones by the Filterra inlet to allow for entry of trash during a storm event. • Replace Filterra grates correctly using appropriate lifting or moving tools, taking care not to damage the plant. 5. Plant health evaluation and pruning or replacement as necessary • Examine the plant’s health and replace if necessary. • Prune as necessary to encourage growth in the correct directions 6. Clean area around Filterra • Clean area around unit and remove all refuse to be disposed of appropriately. 7. Complete paperwork • Deliver Maintenance Report and photographs to appropriate location (normally Contech during maintenance contract period). • Some jurisdictions may require submission of maintenance reports in accordance with approvals. It is the responsibility of the Owner to comply with local regulations. Record on Maintenance Report the following: Height above Grate _____________________(ft) Width at Widest Point _____________________(ft) Health healthy | unhealthy Damage to Plant yes | no Plant Replaced yes | no www.ContechES.com/filterra | 800-338-1122 11 Maintenance Checklist Filterra Inspection & Maintenance Log Filterra System Size/Model: _____________________________Location: ____________________________________________ Drainage System Failure Problem Conditions to Check Condition that Should Exist Actions Inlet Excessive sediment or trash accumulation. Accumulated sediments or trash impair free flow of water into Filterra. Inlet should be free of obstructions allowing free distributed flow of water into Filterra. Sediments and/or trash should be removed. Mulch Cover Trash and floatable debris accumulation. Excessive trash and/or debris accumulation. Minimal trash or other debris on mulch cover. Trash and debris should be removed and mulch cover raked level. Ensure bark nugget mulch is not used. Mulch Cover “Ponding” of water on mulch cover. “Ponding” in unit could be indicative of clogging due to excessive fine sediment accumulation or spill of petroleum oils. Stormwater should drain freely and evenly through mulch cover. Recommend contact manufacturer and replace mulch as a minimum. Vegetation Plants not growing or in poor condition. Soil/mulch too wet, evidence of spill. Incorrect plant selection. Pest infestation. Vandalism to plants. Plants should be healthy and pest free.Contact manufacturer for advice. Vegetation Plant growth excessive. Plants should be appropriate to the species and location of Filterra. Trim/prune plants in accordance with typical landscaping and safety needs. Structure Structure has visible cracks. Cracks wider than 1/2 inch or evidence of soil particles entering the structure through the cracks. Vault should be repaired. Maintenance is ideally to be performed twice annually. Date Mulch & Debris Removed Depth of Mulch Added Mulch Brand Height of Vegetation Above Grate Vegetation Species Issues with System Comments 1/1/17 5 – 5 gal Buckets 3” Lowe’s Premium Brown Mulch 4’Galaxy Magnolia - Standing water in downstream structure - Removed blockage in downstream structure www.ContechES.com/filterra | 800-338-112212 Appendix 1 – Filterra® Activation Checklist Project Name: ________________________________________Company: ______________________________________________ Site Contact Name: _______________________________________Site Contact Phone/Email: ____________________________ Site Owner/End User Name: _________________________Site Owner/End User Phone/Email: ____________________________ Preferred Activation Date: ___________________________________(provide 2 weeks minimum from date this form is submitted) Site Designation System Size Final Pavement / Top Coat Complete Landscaping Complete / Grass Emerging Construction materials / Piles / Debris Removed Throat Opening Measures 4” Min. Height Plant Species Requested  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No  Yes  No NOTE: A charge of $500.00 will be invoiced for each Activation visit requested by Customer where Contech determines that the site does not meet the conditions required for Activation. ONLY Contech authorized representatives can perform Activation of Filterra systems; unauthorized Activations will void the system warranty and waive manufacturer supplied Activation and 1st Year Maintenance. Attach additional sheets as necessary. Signature Date ENGINEERED SOLUTIONS www.ContechES.com/filterra | 800-338-1122 13 Appendix 2 – Planting Requirements for Filterra® Systems Plant Material Selection • Select plant(s) as specified in the engineering plans and specifications. • Select plant(s) with full root development but not to the point where root bound. • Use local nursery container plants only. Ball and burlapped plants are not permitted. • For precast Filterra systems with a tree grate, plant(s) must not have scaffold limbs at least 14 inches from the crown due to spacing between the top of the mulch and the tree grate. Lower branches can be pruned away provided there are sufficient scaffold branches for tree or shrub development. • For precast Filterra systems with a tree grate, at the time of installation, it is required that plant(s) must be at least 6” above the tree grate opening at installation for all Filterra configurations. This DOES NOT apply to Full Grate Cover designs. • Plant(s) shall not have a mature height greater than 25 feet. • For standard 21” media depth, a 7 – 15 gallon container size shall be used. Media less than 21” (Filterra boxes only) will require smaller container plants. • For precast Filterra systems, plant(s) should have a single trunk at installation, and pruning may be necessary at activation and maintenance for some of the faster growing species, or species known to produce basal sprouts. Plant Installation • During transport protect the plant leaves from wind and excessive jostling. • Prior to removing the plant(s) from the container, ensure the soil moisture is sufficient to maintain the integrity of the root ball. If needed, pre-wet the container plant. • Cut away any roots which are growing out of the container drain holes. Plants with excessive root growth from the drain holes should be rejected. • Plant(s) should be carefully removed from the pot by gently pounding on the sides of the container with the fist to loosen root ball. Then carefully slide out. Do not lift plant(s) by trunk as this can break roots and cause soil to fall off. Extract the root ball in a horizontal position and support it to prevent it from breaking apart. Alternatively the pot can be cut away to minimize root ball disturbance. • Remove any excess soil from above the root flare after removing plant(s) from container. • Excavate a hole with a diameter 4” greater than the root ball, gently place the plant(s). • If plant(s) have any circling roots from being pot bound, gently tease them loose without breaking them. • If root ball has a root mat on the bottom, it should be shaved off with a knife just above the mat line. • Plant the tree/shrub/grass with the top of the root ball 1” above surrounding media to allow for settling. • All plants should have the main stem centered in the tree grate (where applicable) upon completion of installation. • With all trees/shrubs, remove dead, diseased, crossed/rubbing, sharply crotched branches or branches growing excessively long or in wrong direction compared to majority of branches. • To prevent transplant shock (especially if planting takes place in the hot season), it may be necessary to prune some of the foliage to compensate for reduced root uptake capacity. This is accomplished by pruning away some of the smaller secondary branches or a main scaffold branch if there are too many. Too much foliage relative to the root ball can dehydrate and damage the plant. • Plant staking may be required. www.ContechES.com/filterra | 800-338-112214 Mulch Installation • Only mulch that has been meeting Contech Engineered Solutions’ mulch specifications can be used in the Filterra system. • Mulch must be applied to a depth of 3” evenly over the surface of the media. Irrigation Requirements • Each Filterra system must receive adequate irrigation to ensure survival of the living system during periods of drier weather. • Irrigation sources include rainfall runoff from downspouts and/or gutter flow, applied water through the tree grate or in some cases from an irrigation system with emitters installed during construction. • At Activation: Apply about one (cool climates) to two (warm climates) gallons of water per inch of trunk diameter over the root ball. • During Establishment: In common with all plants, each Filterra plant will require more frequent watering during the establishment period. One inch of applied water per week for the first three months is recommended for cooler climates (2 to 3 inches for warmer climates). If the system is receiving rainfall runoff from the drainage area, then irrigation may not be needed. Inspection of the soil moisture content can be evaluated by gently brushing aside the mulch layer and feeling the soil. Be sure to replace the mulch when the assessment is complete. Irrigate as needed**. • Established Plants: Established plants have fully developed root systems and can access the entire water column in the media. Therefore irrigation is less frequent but requires more applied water when performed. For a mature system assume 3.5 inches of available water within the media matrix. Irrigation demand can be estimated as 1” of irrigation demand per week. Therefore if dry periods exceed 3 weeks, irrigation may be required. It is also important to recognize that plants which are exposed to windy areas and reflected heat from paved surfaces may need more frequent irrigation. Long term care should develop a history which is more site specific. ** Five gallons per square yard approximates 1 inch of water Therefore for a 6’ by 6’ Filterra approximately 20-60 gallons of water is needed. To ensure even distribution of water it needs to be evenly sprinkled over the entire surface of the filter bed, with special attention to make sure the root ball is completely wetted. NOTE: if needed, measure the time it takes to fill a five gallon bucket to estimate the applied water flow rate then calculate the time needed to irrigate the Filterra. For example, if the flow rate of the sprinkler is 5 gallons/minute then it would take 12 minutes to irrigate a 6’ by 6’ filter. Notes ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ ___________________________________________________________________________________________________________ PDF 1/18 © 2018 Contech Engineered Solutions LLC, a QUIKRETE Company 9025 Centre Pointe Drive, Suite 400 West Chester, OH 45069 info@conteches.com | 800-338-1122 www.ContechES.com ALL RIGHTS RESERVED. PRINTED IN THE USA. NOTHING IN THIS CATALOG SHOULD BE CONSTRUED AS A WARRANTY. APPLICATIONS SUGGESTED HEREIN ARE DESCRIBED ONLY TO HELP READERS MAKE THEIR OWN EVALUATIONS AND DECISIONS, AND ARE NEITHER GUARANTEES NOR WARRANTIES OF SUITABILITY FOR ANY APPLICATION. CONTECH MAKES NO WARRANTY WHATSOEVER, EXPRESS OR IMPLIED, RELATED TO THE APPLICATIONS, MATERIALS, COATINGS, OR PRODUCTS DISCUSSED HEREIN. ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND ALL IMPLIED WARRANTIES OF FITNESS FOR ANY PARTICULAR PURPOSE ARE DISCLAIMED BY CONTECH. SEE CONTECH’S CONDITIONS OF SALE (AVAILABLE AT WWW.CONTECHES.COM/COS) FOR MORE INFORMATION. ® Bioretention Systems ENGINEERED SOLUTIONS Page 10 King County Drainage Maintenance Standards for Commercial and Multifamily Drainage Facilities E-8 Dispersion Trench—Vegetation: Any vegetation growing on dispersion trench. Maintenance Necessary to Bring to Standard: Remove vegetation including root system. Pipe/Culvert Definition: A conveyance culvert of varying diameter. May be constructed of concrete pipe (CP), corrugated metal pipe (CMP), or smooth wall high density polyethylene pipe (HDPP). Defect Number & Defect: F-1 General—Sediment & Debris: Accumulated sediment and/or debris that exceeds 20% of the diameter of the pipe. Maintenance Necessary to Bring to Standard: Clean pipe of all sediment and debris. Refer to the disposal guidelines in Appendix A for instructions on disposal of trash, debris and sediment. F-2 Vegetation—Overgrowth: Vegetation that reduces free movement of water through pipes. Maintenance Necessary to Bring to Standard: Remove all vegetation so water flows freely through pipes. F-3 Structural—Protective Coating is Damaged: Rust is causing more than 50% deterioration to any part of the pipe. Maintenance Necessary to Bring to Standard: Repair or replace pipe. F-4 Structural—Joints: Joints are visibly misaligned, or culvert alignment is disrupted. Maintenance Necessary to Bring to Standard: Realign/reconnect affected culvert. F-5 Structural—Damaged Pipe: Any dent that decreases the cross section area of pipe by more than 20%. Maintenance Necessary to Bring to Standard: Repair or replace pipe. Ditch Definition: Conveyance system. May be U-shaped or trapezoidal with flat bottom. May be rock lined. A ditch is not the same as a bioswale (See Section M. Other—Specific to Bioswale). Defect Number & Defect: G-1 General—Trash & Debris: Trash and debris exceeds 1 cubic foot per 1,000 square feet of ditch and slopes. Maintenance Necessary to Bring to Standard: Clear trash and debris from ditch. Refer to the disposal guidelines in Appendix A for instructions on disposal of trash, debris and sediment. G-2 General—Sediment: Accumulated sediment that exceeds 20% of the design depth. Maintenance Necessary to Bring to Standard: Clean/flush ditch of all sediment and debris so that it matches design. Refer to the disposal guidelines in Appendix A for instructions on disposal of trash, debris and sediment. F. G.