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Prelim Drain & Erosion Controlr BEEHIVE MANAGEMENT GROUP, INC. EASTHAVEN VILLA ADDITION 311 CULLENS ROAD, NORTHWEST YELM, WA 98597 DRAINAGE AND EROSION CONTROL PRELIMINARY REPORT JULY 11, 2002 ~ Easthaven Assisted Care Facility Addition, Yelm, WA PRELIMINARY REPORT PROJECT INFORMATION Project: Easthaven Assisted Care Facility Addition Prepared: 7-10-02 Prepared For: Easthaven Villa, LLC 311 Cullens Road NW Yelm, WA 98597 503-357-3793 Contact: Marvin Pratt REVIEWING AGENCY Jurisdiction: City of Yelm Project Number: [] Project Contact: Dave Gibson PROJECT ENGINEER Prepared By: MC Squared, Inc. 1235 E. 4~' Avenue Suite 101 Olympia, WA 98506 PH. 360-754-9339 FAX 360-352-2044 Project Contact: Mark J. Leingang, PE Project Number: 22234-C File Name/Number: m:projects/falter architecture/easthaven/documents PROJECT ENGINEER'S CERTIFICATION I hereby certify that this Preliminary Drainage Report for the Easthaven Assisted Care Facility Addition in Yelm, WA has been prepared by me or under by supervision and meets the intent of the City of Yelm Development Guidelines unless noted otherwise, and normal standards of engineering practice. I understand that the City of Yelm does not and will not assume liability for the sufficiency, suitability, or performance of drainage facilities designed for this development. MC Squared, Inc. j•a~~ c~ ~- ~~L pig -11 1 ~ Ea~thaven Assisted Care Facility Addition. Yelm. WA PRELIMINARY REPORT Table of Contents Part I Drainage Report SECTION 1 - EXISTING CONDITIONS 3 SECTION 2 - PROJECT DESCRIPTION 4 SECTION 3 - INFILTRATION RATES/SOILS REPORT (> SECTION 4 - WELLS & SEPTIC SYSTEMS SECTION 5 - FUEL TANKS SECTION 6 - SUB-BASIN DESCRIPTION SECTION 7 - ANALYSIS OF 100-YEAR FLOOD '7 SECTION 8 - AESTHETIC CONSIDERATIONS FOR STORMWATER FACILITIES 7 SECTION 9 - DOWNSTREAM CONSIDERATIONS 7 SECTION 10 - COVENANTS, DEDICATIONS, EASEMENTS 7 SECTION 11 - PROPERTY OWNERS ASSOCIATION ARTICLES OF INCORPORATION 7 Part II Erosion Control Report SECTION 1 - CONSTRUCTION SEQUENCE AND PROCEDURE 8 SECTION 2 - TRAPPING SEDIMENT g SECTION 3 - PERMANENT EROSION CONTROL & SITE RESTORATION 9 SECTION 4 - GEOTECHNICAL ANALYSIS AND REPORT 9 SECTION 5 - INSPECTION SEQUENCE 9 SECTION 6 - CONTROL OF POLLUTANTS OTHER TRAN SEDIMENTS 10 Part III Maintenance Plan SECTION 1 - REQUIRED MAINTENANCE 13 SECTION 2 - RESPONSIBLE ORGANIZATION x SECTION 3 - VEGETATION MANAGEMENT PLAN x SECTION 4 - SOURCE CONTROL x Appendices Appendix I Drainage Calculations Pending Appendix II Soils Report/SCS Soils Map and Description Appendix III Vicinity Map Appendix IV STORMFILTER® Product/Maintenance Information Appendix V Thurston County GeoData Query Results (Excerpt) Appendix VI Prelimary Drainage and Erosion Control Plan MC Squared, Inc. 2 ~, Ea~thaven Assisted Care Facility Addition, Yelm, WA PRELIMINARY REPORT The format of this report follows the outline provided in the Drainage Design and Erosion Control Manual (DDECM) for Thurston County. DOE Standards have been used for the design, however. SECTION 1 -EXISTING CONDITIONS The 0.61-acre site is located within the City of Yelm, immediately southwest of the existing Easthaven Villa Site. The site is currently used for growing Christmas trees and has recently been surveyed for this addition. There is no significant off-site flow tributary to the site; a minor portion of the land to the west gently slopes to the site, and surface water can be assumed to sheet flow onto the property. The amount of surface water is limited however because the soils are very well drained gravels and sands. Soils on site are Spanaway gravelly sandy loam according to the Thurston County Soil Survey published by the Soils Conservation Service. There is an existing pond that serves as an infiltration facility for the existing assisted living facility. It is not adequately sized to handle the addition. The conveyance system to the pond will not handle the additional flows from the new addition. A new system will be designed. The project site is located in an aquifer sensitive area. We will need to provide treatment of the runoff prior to infiltration. This project will comply with the intent of the stormwater treatment requirements of the City of Yelm development guidelines. MC Squared, Inc. 3 Eacthaven Assisted Care Facility Addition Yelm WA PRELIMINARY REPORT SECTION 2 -PROJECT DESCRIPTION Project Proponent: Easthaven Villa, LLC 311 Cullens Road NW Yelm, WA 98597 Marvin Pratt 503-357-3793 Total Project Area: ±0.61 Acres Site Address: 311 Cullens Road NW Yelm, WA 98597 Required Permits: Grading, utility, paving, building, plumbing, mechanical, electrical, etc. Sec/Township/Range: NE '/a Section 24, Township 17 North, Range 1 East, W.M., Thurston County, WA Zoning: Commercial The proponent proposes to add a 12,600 sf addition to an existing assisted care facility and parking for approximately 11 cars. Frontage improvements on Cullens Road are to be included for this project. The owner proposes to add a stormwater system for collection, conveyance, treatment and discharge of runoff to an underground infiltration gallery in the new drive on the developed project site. The system will be enhanced to accommodate landscape islands and new drain lines for roof and courtyard runoff. Site development will be constructed in two phases. The first phase will include erosion control measures, site clearing, and demolition of asphalt, grading, storm drainage improvements, and underground utilities such as power, cable, water, sewer and telecommunications. The second phase will include construction of the building, paving, site concrete work, landscaping, pavement restoration, seal coating, and striping. Site development will increase the total impervious area. Currently, small trees, with trunk diameter less than 12 inches, cover the entire site. Development will include creation of approximately 0.22 acres of access road and parking, which is treatable impervious surface. There will be approximately 0.10 acres of perimeter landscaping, and building area landscaping. The building will add approximately 0.29 acres of clean impervious surface. This will increase the site's impervious area to approximately 0.51 acres. MC Squared, Inc. 4 j Ea~thaven Assisted Care Facility Addition, Yelm, WA PRELIMINARY REPORT Development Coverage Summary Impervious Roof Area: Impervious Paved/Concrete Area: Landscaped or Pervious Area: Totals A. Stormwater Treatment Existing Proposed 0 ac ±0.29 ac 0 ac ±0.22ac 0.61 ac ±0.10 ac ±0.61 ac ±0.61 ac The effect of lack of relief, lack of area and tight setbacks combine to eliminate several treatment BMPs; the following systems have been considered for this site: Bioswale Option: The proposed site layout and lack of topographic relief across The site makes it difficult to achieve significant success with biofiltration swales or filter strips. This BMP was not explored for the project. Wet Pond Option: This is not a feasible treatment measure for this site, because a suitable area is not available to accommodate the pond's 3-foot permanent pool depth, 3:1 length to width ratio, 3:1 side slopes, and the depth required for site drainage. This BMP was not explored for the project. Stormfilter®Option: This product, distributed by Stormwater Management, Inc. is an appropriate treatment BMP for this project. A single Stormfilter®catch basin CBSF-3-SD unit would treat the 6-month flow rate of 0.20 cfs. The unit could be placed in-line with the proposed 8-inch storm drain, just upstream of the infiltration gallery. B. C. Preferred Treatment Alternative: After considering the treatment options above, we have determined that the best option is the Stormfilter®option. We recommend this to City of Yelm staff as the most practical and environmentally beneficial option. Stormwater Storage: Due to the excessively drained soils, the infiltration gallery will be sized to serve as both detention and disposal. Both will occur on site. All stormwater runoff will be infiltrated on site. There will not be a release offsite. Roof Runoff: Roof runoff from the proposed addition will be tight lined to drywells for infiltration. The roof leaders will not be combined with the proposed parking/asphalt treatable infiltration system. MC Squared, Inc. 5 Ea;thaven Assisted Care Facility Addition Yelm WA PRELIMINARY REPORT D. Landscape Area: In general, parking lot landscape area runoff will sheet flow to driveway and parking areas for collection in the site's stormwater system. Some areas adjacent to the buildings will require yard drains to collect runoff for discharge to the drywell system mentioned above for roof drains. SECTION 3 -INFILTRATION RATES/SOILS REPORT The Soil Conservation Service (SCS) soil survey of Thurston County classifies the onsite soils as "Spanaway Gravelly Sandy Loam, 0 to 3 percent slopes". A typical soil profile is described by SCS as follows: "These deep, somewhat excessively drained soils are on terraces. It formed in glacial outwash and volcanic ash. For the SCS soils description and map, see Appendix II. SECTION 4 -WELLS & SEPTIC SYSTEMS The owner is not aware of any abandoned or existing wells on-site. Water service for the proposed project will be provided by the City of Yelm. The existing building has a STEP system that serves its sanitary sewer needs. No abandoned or existing septic systems were identified on-site for the property utilized for the addition during MC Squared, Inc.'s site investigation. The addition's sanitary sewer needs will be handled by a STEP system. Sewer service will be provided by the City of Yelm. SECTION 5 -FUEL TANKS No fuel tanks were located during our site inspection. The owner is not aware of any existing tanks in the project area. SECTION 6 -SUB-BASIN DESCRIPTION The site is situated within the City of Yelm commercial district. A minor amount of off-site runoff from the west is tributary to the site. However, given the permeable soil, any runoff from the west is assumed to be negligible. The other existing drainage conditions and systems are detailed in Section 1 -Existing Conditions and is shown on Sheet C- 2 ofthe project civil engineering drawings, (enclosed in Appendix I). No hazardous materials are expected to be handled or transported within the site other than cleaning/maintenance products associated with janitorial operations. MC Squared, Inc. g Easthaven Assisted Care Facility Addition Yelm WA PRELIMINARY REPORT SECTION 7 -ANALYSIS OF 100-YEAR FLOOD Preliminary research shows that the site is not in a 100-year flood hazard area. SECTION 8 -AESTHETIC CONSIDERATIONS FOR STORMWATER FACILITIES All pervious areas will be vegetated and landscaped to provide an aesthetically pleasing environment per the requirements of the City. Landscaping plans have been prepared by the landscape architectural design firm of [to be determined] SECTION 9 -DOWNSTREAM CONSIDERATIONS Runoff from the site will be infiltrated on site. There are not any downstream impacts anticipated. SECTION 10 -COVENANTS, DEDICATIONS, EASEMENTS On-site storm lines, catch basins, and roof drains will require routine maintenance. A maintenance schedule is included in Part III of this report. The owner's maintenance crews will maintain parking lot storm piping systems and catch basins. The building owners will maintain building roof drain lines. SECTION 11-PROPERTY OWNERS ASSOCIATION ARTICLES OF INCORPORATION In light of the commercial nature of this project, special covenants covering landscape, maintenance, signage, stormwater and site maintenance will not be applicable. The building owner will perform maintenance of storm drainage facilities. The building owners will perform maintenance of the roof drain lines and courtyard drains adjacent to the building. MC Squared, Inc. 7 Easthaven Assisted Care Facility Addition. Yelm WA PRELIMINARY REPORT SECTION 1 -CONSTRUCTION SEQUENCE AND PROCEDURE Development of the property will include site grading and erosion control measures designed to contain silt and soil within the project boundaries during construction until permanent erosion control is in place. Erosion sedimentation control will be achieved by a combination of structural/vegetative cover measures and construction practices tailored to fit the site. Best Construction Management Practices (BMPs) will be employed to properly demolish, clear and grade the site and to schedule construction activities. Before any construction begins on-site, erosion control facilities shall first be installed. The contractor shall refer to the erosion control plans. The planned construction sequence is as follows: 1. Schedule preconstruction meeting with City.. 2. Install temporary gravel construction entrance (as needed). 3. Install inlet protection for existing catch basins per Thurston County DDECM details 38 and 139 as shown on civil plans. 4. Install filter fabric fence (as needed). 5. Perform asphalt demolition, clearing, earthwork operations, and foundation excavation. 6. Install storm drainage improvements; install or relocate other utility lines. 7. Install inlet protection for all new on-site catch basins. 8. Hydroseed or cover all exposed areas subject to erosion, i.e., steep slopes, landscape islands, etc. 9. Designate an area for washing of equipment and concrete trucks to control wash down runoff and eliminate entry into storm drainage systems. 10. Complete building and site improvements. 11. Remove temporary erosion control facilities once site landscaping is stabilized. SECTION 2 -TRAPPING SEDIMENT The on-site soils belong to the Spanaway soil group and have slight erosion potential according to the SCS. If necessary, a stabilized construction entrance shall be installed at a single entry point to the site to prevent vehicles from tracking soil away from the disturbed areas. If sediment is tracked off-site, sediment shall, on a daily basis, be swept or shoveled from paved surfaces and not washed into the storm system. Unless the City inspector approves otherwise, the contractor shall not be allowed to leave disturbed areas greater than 5,000 sf, that are to be left unworked for more than 30 days uncovered during the rainy season from November 1 through March 31. Mulch, sodding or plastic covering will be used to prevent erosion in these areas. MC Squared, Inc. g Easthaven Assisted Care Facility Addition, Yelm, WA PRELIMINARY REPORT During construction, the contractor may also be required to install filter fabric fencing, as needed, and/or as directed by the engineer, or city inspector. SECTION 3 -PERMANENT EROSION CONTROL & SITE RESTORATION All disturbed areas will be paved, covered with a building or landscaped with ground cover, shrubbery or trees. SECTION 4 - GEOTECHNICAL ANALYSIS AND REPORT A geo-technical engineering study was not prepared to address site work issues. No on- site slopes exceed 15%. An infiltration test is pending for stormwater infiltration system design. SECTION 5 -INSPECTION SEQUENCE In addition to the normal City inspections, the Project Engineer shall inspect the facilities related to stormwater treatment, erosion control, storage and conveyance during construction. At a minimum, the following items shall be inspected at the time specified: The erosion control facilities shall be inspected before the start of clearing and grading to ensure the following structures are in place: a. Construction Entrance (if installed) b. Filter Fabric Fences (if installed) c. Catch Basin Inlet Protection 2. The conveyance systems shall be inspected after construction of the facility, but before the project is completed to ensure the following are in working order: a. Parking Lot Surface Drainage b. Storm Lines, Catch Basins and Yard Drains 3. The permanent site restoration measures shall be inspected after landscaping is completed. A final inspection shall be performed to verify final grades, setting of control structures and all necessary information to complete Thurston County's Engineer's Construction Inspection Report Form and Commercial Agreement To Maintain Stormwater Facilities. These documents must be completed prior to final City construction approval. MC Squared, Inc. g Easthaven Assisted Care Facility Addition, Yelm, WA PRELIMINARY REPORT SECTION 6 -CONTROL OF POLLUTANTS OTHER THAN SEDIMENTS Washout from concrete trucks shall not be dumped into the storm drain, or onto soil or pavement, which carries stormwater runoff. It can be dumped into a designated area to be later backfilled or hardened and broken up for disposal into a dumpster. The Contractor will be required to designate a wash down area for equipment and concrete trucks. MC Squared, Inc. 10 Easthaven Assisted Care Facility Addition. Yelm. WA PRELIMINARY REPORT INSTRUCTIONS The following pages contain maintenance needs for most of the components that aze part of the site drainage system. Advise the City of Yelm if there are any components that are missing from these pages. Ignore the requirements that do not apply to the system. Plan to complete a checklist for all system components on the following schedule: 1) Monthly from November through April. 2) Once in late summer (preferable September). 3) After any major storm (use "1" in 24 hours as a guideline). Using photocopies of these pages, check off the problems you looked for each time an inspection was performed. Add comments on problems found and actions taken. Keep these "checked" sheets in your files, as they will be used to write your annual report (due in May). Some items do not need to be looked at every time an inspection is done. Use the suggested frequency at the left of each item as a guideline for your inspection. Call the City for technical assistance if needed. MC Squared, Inc. 11 Easthaven Assisted Care Facility Addition, Yelm. WA PRELIMINARY REPORT Inspection-Period: MAINTENANCE PROGRAM COVER SHEET Number of Sheets Attached: Date Inspected: Name of Inspector: Inspector's Signature: MC Squared, Inc. 12 Easthaven Assisted Care Facility Addition, Yelm, WA PRELIMINARY REPORT SECTION 1-REQUIRED MAINTENANCE The drainage facilities will require occasional maintenance. The following general requirements are the minimum requirements as set forth in the Drainage Design and Erosion Control Manual of Thurston County. The required maintenance for storm drainage facilities and frequency of maintenance are as follows: Maintenance Checklist for Conveyance Systems (Pipes and Swales) MC Squared, Inc. 13 APPENDIX 1 DRAINAGE CALCULATIONS (PENDING) APPENDIX 11 BRADLEY-NOBLE SOILS/INFILTRATION REPORT (PENDING) ;ton County, Washington jed areas make up about 10 percent of the total ige. rmeability is moderately rapid in the Spana soil. able water capacity is moderate. Effective rooting is 20 to 40 inches. A seasonal high water table is lepth of about t 2 to 36 inches from November to Runoff is slow, and the hazard of water erosion is st areas are used as hayland and pasture. This ;suited to hay and pasture. The main limitations e seasonal high water table and the moderate ble water capacity. Proper stocking rates, pasture ~n, and restricted grazing during wet periods help ~p the pasture in good condition and protect the om erosion. Rotation grazing helps to maintain the ~ of forage. Periodic mowing helps to maintain m growth, discourages selective grazing, and GIs weeds. In most years irrigation is needed for ium production. Sprinkler irrigation is the best ~d of applying water. The amount of water applied i be sufficient to wet the root zone but small ~h to minimize the leaching of plant nutrients. 'w areas are used as woodland. On the basis of a gar site curve, the estimated site index for as-fir is 144. On the basis of a 50-year site curve, 10. The estimated growth rate of an unmanaged, aged stand of Douglas-fir is 150 cubic feet per per year at 60 years of age. main limitation affecting the harvesting of timber muddiness caused by seasonal wetness. Use of ad and tracked equipment when the soil is wet in ruts and soil compaction. Unsurfaced roads cid trails are soft and can be impassable when ogging roads require suitable surfacing material ~r-round use. Rounded pebbles and cobbles for onstruction are readily available on this unit. The gal high water table limits the use of equipment to rinds. Disturbance of the protective layer of duff minimized by the careful use of wheeled and d equipment. idling establishment is the main concern in the :tion of timber. Reforestation can be plished by planting Douglas-fir seedlings. If the includes seed trees, natural reforestation by red occurs periodically in cutover areas. The seasonal ater table inhibits root respiration and thus results e seedling mortality. When openings are made in ropy, invading brushy plants can prevent the shment of planted Douglas-fir seedlings. imon forest understory plants are cascade ~-grape, salal, vine maple, western brackenfern, ~egon white oak. 89 This map unit is in capability subclass Illw. 110-Spanaway gravelly sandv loam. 0 to 3 ~'a percent sloops. This very deep, somewhat excessively drained soil is on terraces. It formed in glacial outwash and volcanic ash. The native vegetation is mainly grasses, ferns, and a few conifers. Elevation is 100 to 400 feet. The average annual precipitation is 45 to 55 inches, the average annual air temperature is about 51 degrees F, and the average frost-free period is t 50 to 200 days. Typically, the surface layer is black gravelly sandy loam about 15 inches thick. The subsoil is dark yellowish brown very gravelly loam about 5 inches thick. The substratum to a depth of 60 inches or more is dark yellowish brown extremely gravelly sand. Included in this unit are small areas of Alderwood soils on till plains; Everett, Indianola, and Nisqually soils on outwash terraces; and Spana soils in depressions. Also included are small areas of Spanaway soils that have a stony sandy loam surface layer and small areas of Spanaway gravelly sandy loam that have slopes of 3 to 15 percent. Included areas make up about 20 percent of the total acreage. Permeability is moderately rapid in the subsoil of the Spanaway soil and very rapid in the substratum. Available water capacity is low. Effective rooting depth is 60 inches or more. Runoff is slow, and the hazard of water erosion is slight. This unit is used mainly as hayland, pasture, or cropland, as a site for homes, or as a source of gravel. It is also used as woodland. The main limitation affecting hav anti nact~ira is tha low available water capacity. Proper grazing practices, weed control, and fertilizer are needed to ensure maximum quality of forage. Rotation grazing helps to maintain the quality of forage. Periodic mowing helps to maintain uniform growth, discourages selective grazing, and controls weeds. Animal manure can be applied periodically during the growing season. Areas that receive heavy applications should be harrowed at least once a year. In summer, irrigation is needed for maximum production of most forage crops. Sprinkler irrigation is the best method of applying water. The amount of water applied should be sufficient to wet the root zone but small enough to minimize the leaching of plant nutrients. This unit is suited to crops. Wheat, oats, strawberries, raspberries, blackberries, and sweet corn are commonly grown. The main limitation is the low available water capacity. In summer, irrigation is needed for maximum production of most crops. ;, 'i r ~~SHINGTON - SHEET NUMBER 2~1 ,. . -.+'~+.5' ~' -.. nd ~r~ '~~Y iI~ t V r~`t ~( W~. ` ~i^IiYW ~'~ `'r - r y, , ; ~ ._ y' ,k_tl `Ck~ 1 r ~ ,, ~ ~ ~ . , G j' j" Y '~' y uw m.} Hf ~ ~ :~ ~~ e ~ rr a " ~ .. S. 4'!, :~ •~, .ran Eti KIL~ME~EFtS ~ ,~E~: t.S..~;;,,. y ~.+ ~~;~ P~J~~-r' ~ti ~ .~ , - dl l , ,rs ~ ~fs ~`~ -.~~ =..'~Y, ~-. .:.~~_ ~t_ :: 105 r P. G t _ ~ ~ mow' .:~•1 .4~! rc~~6 '~R. ."'~5`~~ i>.. s° ~~y #',. ~' . APPENDIX 111 VICINITY MAP APPENDIX IV STORMFILTER CBSF-3-SD PRODUCT AND MAINTENANCE INFORMATION Selecting and Sizing your StormFilter Catch Basin StormFilter Overview The Catch Basin StormFilterT"" (CBSF) consists of a multi-chamber steel, concrete, or plastic catch basin unit that can contain up to four StormFilter ' cartridges. The CBSF is offered both as a standard and as a deep unit. The CBSF is installed flush with the finished grade and is applicable for both constrained lot and retrofit applications. It can also be fitted with an inlet pipe for roof leaders or similar applications. The CBSF unit treats peak water quality design flows up to 0.13 cfs, coupled with an internal weir overflow capacity of 1.0 cfs for the standard unit and up to 3.0 cfs for the deep unit. 'Design operation The CBSF is installed as the primary receiver of runoff, similar to a standard, grated catch basin. The steel and concrete CBSF units each have atraffic- bearing, H-20 lid that allows the filter to be installed in parking lots, and for all practical purposes, take up no land area. Plastic Catch Basin units can be used in landscaped areas and for other non-traffic bearing applications The CBSF consists of a sumped inlet chamber and a cartridge chamber(s). Runoff enters the sumped inlet chamber either by sheet flow from a paved surface or from an inlet pipe discharging directly to the unit vault. The inlet chamber is equipped with an internal baffle, which traps debris and floating oil and grease, and an overflow weir. While in the inlet chamber, heavier solids are allowed to settle into the deep sump, while lighter solids and soluble pollutants are directed under the baffle and into the cartridge chamber through a port between the baffle and the overflow weir. Once in the cartridge chamber, polluted water ponds and percolates horizontally through the media in the filter cartridges. Treated water collects in the cartridge's center tube from where it is directed by an under-drain manifold ~~ to the outlet pipe on the downstream side of the overflow weir and discharged. When flows into the CBSF exceed the water quality design value, excess water spills over the overflow weir, bypassing the cartridge bay, and discharges to the outlet pipe. Applications The CBSF is particularly useful where small flows are being treated or for sites that are flat and there is little available hydraulic head to spare. The unit is ideal for applications in which standard catch basins are to be used. Both water quality and catchment issues can be resolved with the use of the CBSF. Retro-Fit The retrofit market has many possible applications for the CBSF. The CBSF can be installed by replacing an existing catch basin without having to "chase the grade," thus reducing the high cost of re-piping the storm system. Special Considerations When designing the CBSF into your system, you should consider the following: • Additional information on the non-traffic bearing plastic Catch Basin units is available from the Stormwater Management Engineering Department. • If an inlet pipe is used, a deep unit is recommended in order to minimize the effect of standing water in the upstream system. • Standing water in the inlet bay may lead to standing water in the inlet pipe. • Additional sorbent and oil treatment components are available for the CBSF. See the "Other Products' section for more information. I SF T 800.548.4667 F 800.561.1271 W stormwaterinc.com SF-33 Selecting and Sizing your StormFilter Sizing the Catch Basin StormFilter To determine the size of your Catch Basin StormFilter. 1. Determine the number of cartridges required to treat your water quality flow rate. See "Determining the number of StormFilter cartridges" for instructions on how to calculate this value. 2. Determine the type of material that you want to use: steel, concrete, or plastic. Refer to Table 3 and corresponding footnotes to determine the configurations offered for each material. 3. Locate the number of required cartridges in the Catch Basin configuration options table below. 4. Use the corresponding StormFilter model number, dimensions, and configuration option for your Catch Basin size. Important: Be sure to specify standard or deep unit. Table 3. Catch Basin StormFilter configuration options'' ° StormFilter Number of Outside Approximate Configuration Options ` Model Cartridges Dimensions ~ Weight (Ibs) Standard Deep CBSF1' 1 L,R 4'9" x 2'S" 650 / 775 ~b b~ b b ~' R CBSF2'~d 2 7'1" x 2'S" 950 / 1150 CBSF3 3 L,R 8'10" x 2'S" 1250 / 1500 b _ OO O O OO b b L R CBSF4 4 10'8" x 2'S" 1550 / 1850 OO OO b ' Concrete catch basin units are available in the CBSF1-L configuration only; plastic catch basin units are available with 1 or 2 cartridges only; steel catch basin units are available in all configurations. If anther configuration or more information is needed, contact the Stormwater Management Engineering Department. b The "b" symbol on the configuration drawings denotes possible inlet pipe locations. Inlet pipes are recommended on deep units only. The inlet pipe can o~ be attached to the grated chamber. ` Inlet pipes installed lower than 1 foot below the grade (standard units; 1'10', deep units) will be partially to completely submerged. ° 2-cartridge catch basin units can be designed with a left or right configuration if needed. Contact the Stormwater Management Engineering Department for details. ~F-34 T 800.548.4667 F 800.561.1271 W stormwaterinc.com Using the flow-based method To determine the number of StormFilter cartridges needed for a highly impervious site (>_ 70% impervious): 1. Calculate the peak flow rate from the water quality storm (Q~a~) for your site using the approved hydrologic models established by your local agency. If there are no agency guidelines, we recommend using the Santa Barbara Urban Hydrograph Method. 2. Calculate the number of cartridges required to treat the peak water quality flow rate (Nn°r„) for your site. . Know = Qveat (449 gpm/cfs / Qcart 9Pm/grt) Notes: • Assume Q~rt = 15 yprrvcan, which is the maximum flow rate that an individual cartridge can treat. In some areas or situations, cartridges with a flow rate other than 15 gPm may be required, resulting in a different Q~rt value. • If the number of cartridges is not a whole number, round the number of cartridges up to the next whole number. APPENDIX V THURSTON COUNTY GEODATA QUERY RESULTS EXCERPTS Thurston GeoDATA Center/Interactive Map Thurston GeoData Center Click here to view results of search. Page 1 of 3 Click on Map to: ~' Zoam In ~' Zoom Out~~ Zoom Factor: t=___J ~ escribe a Parcel ~ !:;escnhe a 1_aver ~ N(easure Distance ~ A,leasure Area ~.: . Search By: .Address: Do not use road suffix (ie St. or Rd.} ~~Street Number (ie 921): C __-Street Name (ie 5tn er Evergreen Park) EOuadrant (ie NW cr SE): 11 digit Parcel Number: Section (ie 05182w}: ~~~Survey Target#?Name: ~~CAPCOM Grid# (ie V-14)' R~`~i~.~~, ~ i ~.: Return to top of page ~ Display Aerial Photos ~ Display Parcel Text Show other ma la ers? none v~, Label Parcels With? Parcel Number 1~s~essor ~~ta Thurston GeoDATA Center/Interactive Map OWNER: EAST HAVEN VILLA LLC (Due to space restrictions only 1 owner is listed) Address: 311 CULLENS ST NW City: YELM State: WA, 98597 Parcel#: 21724140502 Site Address: 311 CULLENS ST NW Site City: YELM Site Zip: 98597 Section: s24171E Legal Description: 24-17-1E SE NE BEG AT NE COR SE NE W ALG NLN 335.86F TO POB 536-29 -30-W 364.21F S53- Usecode: 17 - INST-LODGING Tax Code Area: 170 Taxable: Y Property Type: COM Total Acres: 2.18 Land Value: 104900 Building Value: 1928700 Total Value: 2033600 Current Use: N Exemptions: None Last Sale Recorded #: Last Sale Date: Unknown Last Sale Price: Unknown Transaction includes additional properties: Unknown Last Sellers Name: Unknown Return to top of page Page 2 of 3 ~l`el~ld~ ~dt~l Thurston GeoDATA Center/Interactive Map Wetlands: No Floodzone: No Flood of 1996: Unknown Winter Flooding of 1996: No High Groundwater Flood Hazards: Unknown Salmon Creek Basin: No 1999 Carlyon Beach Landslide Hazard: None Zoning: R-6 or C-1 Historic Site: No Jurisdiction: YELM Stormwater Rate: No No Shooting Zone: No Animal Control Zone: Yes Weed Containment Area: No Steep Slopes: No Sensitive Areas: No DNR Natural Heritage Data: No Critical Buffers: 200' Wetland Shoreline Management: No Waterbody & Wetland Buffers: Yes Wellhead Prot. Area: Unknown Area of Groundwater Concern: No Elevated Nitrates: No Soil Type: Spanaway gravelly sandy loam, 0 to 3~ slopes Hydric Soil: No Watershed: YELM CREEK Water Service Area: YELM, CITY OF School Service District: YELM Fire Response District: YELM Planning Region: 3 Census Tract Page 3 of 3 County Ordinances ~ Data Descriptions ~ Help ~ Whnt's New ~ TGC Home ~ Hel ful Info ~ Assessor Questions Ecology Shoreline Photographs ~ Thurston County GPS Bnsestntion ,~. . . y..: `~ °~ You are visitor 3fi5,55~ with map request 5,008,742 since. Apri124, 1998 ~~.Af2~l~;~: ~'aircel 1):~ta was last updated on Sunda-, ,Aug 4, 2002 DISCLAIMER: Thurston GeoData Center makes no guarantee of data accuracy and assumes no liability for the data represented here. If questions arise regarding accuracy please contact Thurston County staff. Please do not bookmark this page! Bookmark our home page instead! Thurston GeoDATA Center/Interactive Map Page 1 of 1 • ~ .- Scale: Approx. lInch = 100 Feet 8/7/2002 12:21:45 PM Map Produced By: Thurston GEODATA Center's Internet Map Server APPENDIX VI PRELIMINARY DRAINAGE AND EROSION CONTROL PLAN