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MS 2019-0003; BMW OF CARLSBAD; PRIORITY DEVELOPMENT PROJECT (PDP) STORM WATER QUALITY MANAGEMENT PLAN (SWQMP); 2021-10-18
PRIORITY DEVELOPMENT PROJECT (PDP) STORM WATER QUALITY MANAGEMENT PLAN (SWQMP) FOR BMW OF CARLSBAD 1060 Auto Center Court Carlsbad, CA 92008 CDP2019-0013, DEV2018-0198, MS2019-0003 SWQMP No. TBD ENGINEER OF WORK: Aaron M. Albertson, RCE 65513, Exp. 09/30/23 (Provide Wet Signature and Stamp Above Line) PREPARED FOR: AutoNation Inc. 200 SW 1st Ave, 14th Floor Fort Lauderdale, FL 33301 Tel: (954) 769-6000 PREPARED BY: Today’s Ideas. Tomorrow’s Reality. 4121 Westerly Place, Suite 112 Newport Beach, CA 92660 Tel: (949) 610-8997 DATE: October 18th, 2021 (_ City of Carlsbad C~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 1 of 27 TABLE OF CONTENTS Certification Page………………………………………………………………………………………... 2 Project Vicinity Map……………………………………………………………………………………… 3 FORM E-34: Storm Water Standard Questionnaire………………………………………………….. 4 Site Information…………………………………………………………………………………………... 5 FORM E-36: Standard Project Requirement Checklist…………………………………………...… 13 Summary of PDP Structural BMPs…………………………………………………………………… 14 Attachment 1: Backup for PDP Pollutant Control BMPs……………………………………………. 21 Attachment 1a: DMA Exhibit Attachment 1b: DMA Summary Attachment 1c: Harvest and Use Feasibility Screening Attachment 1d: Categorization of Infiltration Feasibility Condition (Form I-8) Attachment 1e: Pollutant Control BMP Design Worksheets / Calculations LID DCV Calculation Summary San Diego County 85th Percentile Isopluvial Map Worksheet B.5-1: Simple Sizing Method for Biofiltration BMPs (x4) Worksheet B.4-1: Simple Sizing Method for Infiltration BMPs Worksheet B.6-1: Flow-Thru Design Flows BMP Sizing & Detail Sheets Attachment 2: Backup for PDP Hydromodification Control Measures…………………………….. 23 Attachment 2a: Hydromodification Management Exhibit Attachment 2b: Management of Critical Coarse Sediment Yield Areas (WMAA Exhibit) Attachment 2c: Not Included Attachment 2d: Flow Control Facility Design Attachment 3: Structural BMP Maintenance Information…………….…………………….……….. 25 Attachment 4: Single Sheet BMP (SSBMP) Exhibit…………………………………………………. 28 c:~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 2 of 27 CERTIFICATION PAGE Project Name: BMW of Carlsbad Project ID: MS2019-0003/CDP2019-0013 I hereby declare that I am the Engineer in Responsible Charge of design of storm water BMPs for this project, and that I have exercised responsible charge over the design of the project as defined in Section 6703 of the Business and Professions Code, and that the design is consistent with the requirements of the BMP Design Manual, which is based on the requirements of SDRWQCB Order No. R9-2013-0001 (MS4 Permit) or the current Order. I have read and understand that the City Engineer has adopted minimum requirements for managing urban runoff, including storm water, from land development activities, as described in the BMP Design Manual. I certify that this SWQMP has been completed to the best of my ability and accurately reflects the project being proposed and the applicable source control and site design BMPs proposed to minimize the potentially negative impacts of this project's land development activities on water quality. I understand and acknowledge that the plan check review of this SWQMP by the City Engineer is confined to a review and does not relieve me, as the Engineer in Responsible Charge of design of storm water BMPs for this project, of my responsibilities for project design. R.C.E. 65513, Exp. 09/30/23 Engineer of Work's Signature, PE Number & Expiration Date Aaron Albertson Print Name Commercial Development Resources Company 10/18/2021 Date c:~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 3 of 27 PROJECT VICINITY MAP 0 C ,;; i z 8 i5 ~ J 8 I i5 ~ PROJECT LOCATION 1050 AUTO CENTER DR CARLSBAD, CA -·O Q 0----.., .,, _.,-~g.)(l_.. (.9,f'('\ ' ~ l " 1 p -o- tin;;." Carlsbad Flower Fields c:~Commercial Development Resources iii Location Map l I p Legoland0 California Plate 1 Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 4 of 27 [Insert City’s Storm Water Standard Questionnaire (Form E-34) here] c:~Commercial Development Resources C cityof Carlsbad STORM WATER STANDARDS QUESTIONNAIRE Development Services Land Development Engineering 1635 Faraday Avenue (760) 602-2750 www.carlsbadca.gov E-34 I INSTRUCTIONS: To address post-development pollutants that may be generated from development projects, the city requires that new development and significant redevelopment priority projects incorporate Permanent Storm Water Best Management Practices (BMPs) into the project design per Carlsbad BMP Design Manual (BMP Manual). To view the BMP Manual , refer to the Engineering Standards (Volume 5). This questionnaire must be completed by the applicant in advance of submitting for a development application (subdivision, discretionary permits and/or construction permits). The results of the questionnaire determine the level of storm water standards that must be applied to a proposed development or redevelopment project. Depending on the outcome, your project will either be subject to 'STANDARD PROJECT' requirements or be subject to 'PRIORITY DEVELOPMENT PROJECT' (PDP) requirements. Your responses to the questionnaire represent an initial assessment of the proposed project conditions and impacts. City staff has responsibility for making the final assessment after submission of the development application. If staff determines that the questionnaire was incorrectly filled out and is subject to more stringent storm water standards than initially assessed by you , this will result in the return of the development application as incomplete. In this case, please make the changes to the questionnaire and resubmit to the city. If you are unsure about the meaning of a question or need help in determining how to respond to one or more of the questions, please seek assistance from Land Development Engineering staff. A completed and signed questionnaire must be submitted with each development project application. Only one completed and signed questionnaire is required when multiple development applications for the same project are submitted concurrently. PROJECT INFORMATION PROJECT NAME: BMW OF CARLSBAD PROJECT ID: MS2019-0003/ CDP2019-0013 ADDRESS: 1060 Auto Center Court, Carlsbad , CA 92008 APN: 211-080-11-00 The project is (check one): D New Development IZI Redevelopment The total proposed disturbed area is: 161,503 ft2 ( 3.71 ) acres The total proposed newly created and/or replaced impervious area is: 120,934 ft2 ( 2.78 ) acres If your project is covered by an approved SWQMP as part of a larger development project, provide the project ID and the SWQMP # of the larger development project: Project ID: N/A SWQMP#: N/A Then , go to Step 1 and follow the instructions. When completed, sign the form at the end and submit this with your application to the city. E-34 Page 1 of 4 REV 02/16 STEP 1 TO BE COMPLETED FOR ALL PROJECTS To determine if your project is a "development project", please answer the following question: YES NO Is your project LIMITED TO routine maintenance activity and/or repair/improvements to an existing building □ IX] or structure that do not alter the size (See Section 1.3 of the BMP Design Manual for guidance)? If you answered "yes" to the above question, provide justification below then go to Step 5, mark the third box stating "my project is not a 'development project' and not subject to the requirements of the BMP manual" and complete applicant information. Justification/discussion: (e.g. the project includes only interior remodels within an existing building): If you answered "no" to the above question, the project is a 'development project', go to Step 2. STEP2 TO BE COMPLETED FOR ALL DEVELOPMENT PROJECTS To determine if your project is exempt from PDP requirements pursuant to MS4 Permit Provision E.3.b.(3), please answer the following questions: Is your project LIMITED to one or more of the following: YES NO 1. Constructing new or retrofitting paved sidewalks, bicycle lanes or trails that meet the following criteria: a) Designed and constructed to direct storm water runoff to adjacent vegetated areas, or other non- erodible permeable areas; □ IX] b) Designed and constructed to be hydraulically disconnected from paved streets or roads; c) Designed and constructed with permeable pavements or surfaces in accordance with USEPA Green Streets guidance? 2. Retrofitting or redeveloping existing paved alleys, streets, or roads that are designed and constructed in □ [Z] accordance with the USEPA Green Streets guidance? 3. Ground Mounted Solar Array that meets the criteria provided in section 1.4.2 of the BMP manual? □ IX] If you answered "yes" to one or more of the above questions, provide discussion/justification below, then go to Step 5, mark the second box stating "my project is EXEMPT from PDP ... " and complete applicant information. Discussion to justify exemption ( e.g. the project redeveloping existing road designed and constructed in accordance with the USEPA Green Street guidance): If you answered "no" to the above questions, your project is not exempt from PDP, go to Step 3. E-34 Page 2 of 4 REV 04/17 STEP3 TO BE COMPLETED FOR ALL NEW OR REDEVELOPMENT PROJECTS To determine if your project is a PDP, please answer the following questions (MS4 Permit Provision E.3.b.(1 )): YES NO 1. Is your project a new development that creates 10,000 square feet or more of impervious surfaces collectively over the entire project site? This includes commercial, industrial, residential, mixed-use, □ IX] and public development projects on public or private land. 2. Is your project a redevelopment project creating and/or replacing 5,000 square feet or more of impervious surface collectively over the entire project site on an existing site of 10,000 square feet or IZI □ more of impervious surface? This includes commercial, industrial, residential, mixed-use, and public development projects on public or private land. 3. Is your project a new or redevelopment project that creates and/or replaces 5,000 square feet or more of impervious surface collectively over the entire project site and supports a restaurant? A restaurant is a facility that sells prepared foods and drinks for consumption, including stationary lunch counters and □ IX] refreshment stands selling prepared foods and drinks for immediate consumption (Standard Industrial Classification (SIC) code 5812). 4. Is your project a new or redevelopment project that creates 5,000 square feet or more of impervious surface collectively over the entire project site and supports a hillside development project? A hillside □ IX] development project includes development on any natural slope that is twenty-five percent or greater. 5. Is your project a new or redevelopment project that creates and/or replaces 5,000 square feet or more of impervious surface collectively over the entire project site and supports a parking lot? A parking lot is Ix] □ a land area or facility for the temporary parking or storage of motor vehicles used personally for business or for commerce. 6. Is your project a new or redevelopment project that creates and/or replaces 5,000 square feet or more of impervious street, road, highway, freeway or driveway surface collectively over the entire project IZl □ site? A street, road, highway, freeway or driveway is any paved impervious surface used for the transportation of automobiles, trucks, motorcycles, and other vehicles. 7. Is your project a new or redevelopment project that creates and/or replaces 2,500 square feet or more of impervious surface collectively over the entire site, and discharges directly to an Environmentally Sensitive Area (ESA)? "Discharging Directly to" includes flow that is conveyed overland a distance of □ IZI 200 feet or less from the project to the ESA, or conveyed in a pipe or open channel any distance as an isolated flow from the project to the ESA (i.e. not commingled with flows from adjacent lands).* 8. Is your project a new development or redevelopment project that creates and/or replaces 5,000 square feet or more of impervious surface that supports an automotive repair shop? An automotive repair IZI □ shop is a facility that is categorized in any one of the following Standard Industrial Classification (SIC) codes: 5013, 5014, 5541, 7532-7534, or 7536-7539. 9. Is your project a new development or redevelopment project that creates and/or replaces 5,000 square feet or more of impervious area that supports a retail gasoline outlet (RGO)? This category includes □ IZI RGO's that meet the following criteria: (a) 5,000 square feet or more or (b) a project Average Daily Traffic (ADT) of 100 or more vehicles per day. 10. Is your project a new or redevelopment project that results in the disturbance of one or more acres of land Ix] □ and are expected to generate pollutants post construction? 11. Is your project located within 200 feet of the Pacific Ocean and (1 ) creates 2,500 square feet or more of impervious surface or (2) increases impervious surface on the property by more than 10%? (CMC □ IX] 21.203.040) If you answered "yes" to one or more of the above questions, your project is a PDP. If your project is a redevelopment project, go to step 4. If your project is a new project, go to step 5, check the first box stating "My project is a PDP ... " and complete applicant information. If you answered "no" to all of the above questions, your project is a 'STANDARD PROJECT.' Go to step 5, check the second box stating "My project is a 'STANDARD PROJECT' ... " and complete applicant information. E-34 Page 3 of 4 REV 04/17 STEP4 TO BE COMPLETED FOR REDEVELOPMENT PROJECTS THAT ARE PRIORITY DEVELOPMENT PROJECTS (PDP) ONLY Complete the questions below regarding your redevelopment project (MS4 Permit Provision E.3.b.(2)): YES NO Does the redevelopment project result in the creation or replacement of impervious surface in an amount of less than 50% of the surface area of the previously existing development? Complete the percent impervious calculation below: Existing impervious area (A) = 118,892 sq. ft. □ IX] Total proposed newly created or replaced impervious area (B) = 120,934 sq. ft. Percent impervious area created or replaced (B/A)*100 = 102 % If you answered "yes", the structural BMPs required for PDP apply only to the creation or replacement of impervious surface and not the entire development. Go to step 5, check the first box stating "My project is a PDP ... " and complete applicant information. If you answered "no," the structural BM P's required for PDP apply to the entire development. Go to step 5, check the check the first box stating "My project is a PDP ... " and complete applicant information. STEP 5 CHECK THE APPROPRIATE BOX AND COMPLETE APPLICANT INFORMATION IX] My project is a PDP and must comply with PDP stormwater requirements of the BMP Manual. I understand I must prepare a Storm Water Quality Management Plan (SWQMP) for submittal at time of application. □ My project is a 'STANDARD PROJECT' OR EXEMPT from PDP and must only comply with 'STANDARD PROJECT' stormwater requirements of the BMP Manual. As part of these requirements, I will submit a "Standard Project Requirement Checklist Form E-36" and incorporate low impact development strategies throughout my project. Note: For projects that are close to meeting the PDP threshold, staff may require detailed impervious area calculations and exhibits to verify if 'STANDARD PROJECT' stormwater requirements apply. D My Project is NOT a 'development project' and is not subject to the requirements of the BMP Manual. Applicant Information and Signature Box Applicant Name: Aaron Albertson -CDR Applicant Title: Principal Engineer Applicant Signature: Date: . . .. * Environmentally Sens1t1ve Areas include but are not limited to all Clean Water Act Section 303(d) 1mpa1red water bodies; areas designated as Areas of Special Biological Significance by the State Water Resources Control Board (Water Quality Control Plan for the San Diego Basin (1994) and amendments); water bodies designated with the RARE beneficial use by the State Water Resources Control Board (Water Quality Control Plan for the San Diego Basin (1994) and amendments); areas designated as preserves or their equivalent under the Multi Species Conservation Program within the Cities and County of San Diego; Habitat Management Plan; and any other equivalent environmentally sensitive areas which have been identified by the City. IS ox or HV se nrv Th . B ti C"t U O I YES NO City Concurrence: □ □ By: Date: Project ID: E-34 Page 4 of 4 REV 04/17 Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 5 of 27 SITE INFORMATION CHECKLIST Project Summary Information Project Name BMW of Carlsbad Project ID MS2019-0003, CDP2019-0013 Project Address 1060 Auto Center Court Carlsbad, CA 92008 Assessor's Parcel Number (APN) 211-080-11-00 Project Watershed (Hydrologic Unit) Carlsbad 904, Agua Hedionda (904.3) Parcel Area 3.708 Acres ( 161,503 Square Feet) Existing Impervious Area (subset of Parcel Area) 2.729 Acres ( 118,892 Square Feet) Area to be disturbed by the project (Project Area) 3.708 Acres ( 161,503 Square Feet) Project Proposed Impervious Area (subset of Project Area) 2.776 Acres ( 120,934 Square Feet) Project Proposed Pervious Area (subset of Project Area) 0.931 Acres ( 40,568 Square Feet) Note: Proposed Impervious Area + Proposed Pervious Area = Area to be Disturbed by the Project. This may be less than the Parcel Area. c:~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 6 of 27 Description of Existing Site Condition and Drainage Patterns Current Status of the Site (select all that apply): ☑ Existing development ☐ Previously graded but not built out ☐ Agricultural or other non-impervious use ☐ Vacant, undeveloped/natural Description / Additional Information: Existing project site is an automotive dealer and repair complex with onsite AC pavement parking lot, drive aisles and landscape areas. Existing Land Cover Includes (select all that apply): ☑ Vegetative Cover ☐ Non-Vegetated Pervious Areas ☑ Impervious Areas Description / Additional Information: Existing project site is 26% pervious landscape and 74% impervious area (roof, parking lot, sidewalks, etc.) Underlying Soil belongs to Hydrologic Soil Group (select all that apply): ☐ NRCS Type A ☑ NRCS Type B ☐ NRCS Type C ☐ NRCS Type D Approximate Depth to Groundwater (GW): ☐ GW Depth < 5 feet ☐ 5 feet < GW Depth < 10 feet ☐ 10 feet < GW Depth < 20 feet ☑ GW Depth > 20 feet Existing Natural Hydrologic Features (select all that apply): ☐ Watercourses ☐ Seeps ☐ Springs ☐ Wetlands ☑ None Description / Additional Information: N/A c:~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 7 of 27 Description of Existing Site Topography and Drainage: [How is storm water runoff conveyed from the site? At a minimum, this description should answer (1) whether existing drainage conveyance is natural or urban; (2) describe existing constructed storm water conveyance systems, if applicable; and (3) is runoff from offsite conveyed through the site? if so, describe] The existing site is an automotive detail and repair complex. Onsite stormwater flows away from the existing building, across the AC pavement parking lot, to curb and gutter around perimeter of site, then flows into onsite catch basin. The onsite catch basins discharge directly to the City’s storm drain system. Runoff in the perimeter landscaping flows offsite and into existing catch basins in the public-right-of way before joining the City’s storm drain system. The City’s storm drain system discharges to Agua Hedionda Lagoon, then to the Pacific Ocean. c:~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 8 of 27 Description of Proposed Site Development and Drainage Patterns Project Description / Proposed Land Use and/or Activities: The proposed project is the construction of a new BMW dealership with a 2-story building with 1.4 acres of rooftop parking. This will include new onsite AC pavement parking areas, drive aisles, landscape setbacks, landscape islands, and trash enclosure. List/describe proposed impervious features of the project (e.g., buildings, roadways, parking lots, courtyards, athletic courts, other impervious features): Proposed impervious features include a new 2-story building with rooftop parking, AC pavement parking lot with drive aisles, and concrete walkways. The proposed condition will be 75% impervious areas. List/describe proposed pervious features of the project (e.g. landscape areas): Proposed pervious features include landscaped areas along property lines and throughout the project site. In addition, permeable pavers are provided in parking areas to reduce the total impervious area for the project site. Permeable pavers are not considered treatment control BMPs. The proposed condition will be 25% impervious areas. Does the project include grading and changes to site topography? ☑ Yes ☐ No Description / Additional Information: The project site will be regraded to construct a 2-story, at-grade building in the center of the site. The surrounding area in the project site will be regraded to capture all rooftop and parking lot flows onsite. The landscape area along Cannon Road will remain as steep slopes from the property line down to the public right-of-way. Landscape areas along the property line on Car Country Drive and Auto Center Court will continue to slope as it does in existing condition – part of the area will slope towards the road, and part will slope onto the project site. Project site flows will be directed to biofiltration basins (two with partial retention) for treatment and discharge to the underground detention system. The retaining walls along the western property line will remain in place. The project site does not receive run-on from outside property limits. Does the project include changes to site drainage (e.g., installation of new storm water conveyance systems)? ☑ Yes ☐ No Description / Additional Information: New storm drain system, biofiltration basins, biofiltration basins with partial retention and underground detention system to capture, treat, and detain stormwater runoff onsite prior to draining offsite to meet LID and hydromodification requirements. Onsite runoff sheetflows to proposed biofiltration areas (some with partial retention) for treatment prior to discharging to underground detention. Rooftop runoff will be captured and treated via BioClean’s Modular Wetland System (MWS) prior to discharging to the underground detention system. Detention vault outlet structure will drain to the existing private storm drain lateral on Cannon Road. c:~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 9 of 27 Identify whether any of the following features, activities, and/or pollutant source areas will be present (select all that apply): ☑ On-site storm drain inlets ☐ Interior floor drains and elevator shaft sump pumps ☐ Interior parking garages ☐ Need for future indoor & structural pest control ☑ Landscape/Outdoor Pesticide Use ☐ Pools, spas, ponds, decorative fountains, and other water features ☐ Food service ☑ Refuse areas ☐ Industrial processes ☐ Outdoor storage of equipment or materials ☑ Vehicle and Equipment Cleaning ☑ Vehicle/Equipment Repair and Maintenance ☐ Fuel Dispensing Areas ☐ Loading Docks ☑ Fire Sprinkler Test Water ☑ Miscellaneous Drain or Wash Water ☑ Plazas, sidewalks, and parking lots c:~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 10 of 27 Identification of Receiving Water Pollutants of Concern Describe path of storm water from the project site to the Pacific Ocean (or bay, lagoon, lake or reservoir, as applicable): The onsite detention system will discharge to the existing private storm drain lateral at the northwest property corner. Runoff from the perimeter landscaping along Cannon Road flows north to the gutter in the public right-of-way, then to an existing public storm drain inlet approximately 600-ft west of the project site. Runoff from the perimeter landscaping along Car Country Drive flows east to the gutter in the public right-of-way, then north to an existing public storm drain inlet on Car Country Drive near the northeast property corner. Runoff from the perimeter landscaping along Auto Center Court flows south to the gutter in the public right-of-way, then to an existing public storm drain inlet located west of the project site at the end of the cul-de-sac. The existing private storm drain lateral and public storm drain inlets convey flows to the existing City storm drain line flowing west along Cannon Road. This conveys runoff to the Agua Hedionda Lagoon and ultimately drains to the Pacific Ocean. List any 303(d) impaired water bodies within the path of storm water from the project site to the Pacific Ocean (or bay, lagoon, lake or reservoir, as applicable), identify the pollutant(s)/ stressor(s) causing impairment, and identify any TMDLs for the impaired water bodies: 303(d) Impaired Water Body Pollutant(s)/Stressor(s) TMDLs Agua Hedionda Lagoon Indicator Bacteria Indicator Bacteria, Invasive Species, Sedimentation/Siltation Identification of Project Site Pollutants Identify pollutants anticipated from the project site based on all proposed use(s) of the site (see BMP Design Manual Appendix B.6): Commercial Development (>1ac), Parking Lot Pollutant Not Applicable to the Project Site Anticipated from the Project Site Also a Receiving Water Pollutant of Concern Sediment X Nutrients X Heavy Metals X Organic Compounds X Trash & Debris X Oxygen Demanding Substances X Oil & Grease X Bacteria & Viruses X X Pesticides X c:~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 11 of 27 Hydromodification Management Requirements Do hydromodification management requirements apply (see Section 1.6 of the BMP Design Manual)? ☒ Yes, hydromodification management flow control structural BMPs required. ☐ No, the project will discharge runoff directly to existing underground storm drains discharging directly to water storage reservoirs, lakes, enclosed embayments, or the Pacific Ocean. ☐ No, the project will discharge runoff directly to conveyance channels whose bed and bank are concrete-lined all the way from the point of discharge to water storage reservoirs, lakes, enclosed embayments, or the Pacific Ocean. ☐ No, the project will discharge runoff directly to an area identified as appropriate for an exemption by the WMAA for the watershed in which the project resides. Description / Additional Information (to be provided if a 'No' answer has been selected above): N/A Critical Coarse Sediment Yield Areas* *This Section only required if hydromodification management requirements apply Based on the maps provided within the WMAA, do potential critical coarse sediment yield areas exist within the project drainage boundaries? ☐ Yes ☒ No, No critical coarse sediment yield areas to be protected based on WMAA maps If yes, have any of the optional analyses presented in Section 6.2 of the BMP Design Manual been performed? ☐ 6.2.1 Verification of Geomorphic Landscape Units (GLUs) Onsite ☐ 6.2.2 Downstream Systems Sensitivity to Coarse Sediment ☐ 6.2.3 Optional Additional Analysis of Potential Critical Coarse Sediment Yield Areas Onsite ☐ No optional analyses performed, the project will avoid critical coarse sediment yield areas identified based on WMAA maps If optional analyses were performed, what is the final result? ☐ No critical coarse sediment yield areas to be protected based on verification of GLUs onsite ☐ Critical coarse sediment yield areas exist but additional analysis has determined that protection is not required. Documentation attached in Attachment 8 of the SWQMP. ☐ Critical coarse sediment yield areas exist and require protection. The project will implement management measures described in Sections 6.2.4 and 6.2.5 as applicable, and the areas are identified on the SWQMP Exhibit. Discussion / Additional Information: N/A c:~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 12 of 27 Flow Control for Post-Project Runoff* *This Section only required if hydromodification management requirements apply List and describe point(s) of compliance (POCs) for flow control for hydromodification management (see Section 6.3.1). For each POC, provide a POC identification name or number correlating to the project's HMP Exhibit and a receiving channel identification name or number correlating to the project's HMP Exhibit. There is 1 point of compliance (POC) for flow control for hydromodification management for the proposed project: DMA-1 & DMA-2 City SD System POC #1 Agua Hedionda Lagoon DMA-1 flows to City SD system via existing private lateral on Cannon Road. DMA-2 flows to City SD system via existing inlets in the public ROW on Auto Center Court, Car Country Drive, and Cannon Road. POC #1 is located at STA 31+80.00 of existing City storm drain line on Cannon Road, east of Paseo Del Norte, per City Drawing No. 285-2 (sheets 6 and 10). The storm drain system conveys flows west along Cannon Road, then discharges north to Agua Hedionda Lagoon. Has a geomorphic assessment been performed for the receiving channel(s)? ☒ No, the low flow threshold is 0.1Q2 (default low flow threshold) ☐ Yes, the result is the low flow threshold is 0.1Q2 ☐ Yes, the result is the low flow threshold is 0.3Q2 ☐ Yes, the result is the low flow threshold is 0.5Q2 If a geomorphic assessment has been performed, provide title, date, and preparer: N/A Discussion / Additional Information: (optional) N/A Other Site Requirements and Constraints When applicable, list other site requirements or constraints that will influence storm water management design, such as zoning requirements including setbacks and open space, or City codes governing minimum street width, sidewalk construction, allowable pavement types, and drainage requirements. 25’-wide landscape setback along Cannon Road 10’-wide landscape setback along Car Country Drive 10’-wide landscape setback along Auto Center Court Optional Additional Information or Continuation of Previous Sections As Needed This space provided for additional information or continuation of information from previous sections as needed. N/A c:~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 13 of 27 [Insert City’s Standard Project Requirement Checklist Form E-36 (here)] c:~Commercial Development Resources C cityof Carlsbad Project Name: BMW of Carlsbad Project ID: MS2019-0003 STANDARD PROJECT REQUIREMENT CHECKLIST E-36 Project Information DWG No. or Building Permit No.: CDP2019-0013/SDP2019-0005, DWG NO. 529-6A Source Control BM Ps Development Services Land Development Engineering 1635 Faraday Avenue (760) 602-2750 www.carlsbadca.gov All development projects must implement source control BMPs SC-1 through SC-6 where applicable and feasible. See Chapter 4 and Appendix E.1 of the BMP Design Manual (Volume 5 of City Engineering Standards) for information to implement source control BMPs shown in this checklist. Answer each category below pursuant to the following. • "Yes" means the project will implement the source control BMP as described in Chapter 4 and/or Appendix E.1 of the Model BMP Design Manual. Discussion/justification is not required. • "No" means the BMP is applicable to the project but it is not feasible to implement. Discussion/justification must be provided. Please add attachments if more space is needed. • "N/A" means the BMP is not applicable at the project site because the project does not include the feature that is addressed by the BMP (e.g., the project has no outdoor materials storage areas). Discussion/justification may be provided. Source Control Requirement Applied? SC-1 Prevention of Illicit Discharges into the MS4 !XI Yes □ No □ N/A Discussion/justification if SC-1 not implemented: SC-2 Storm Drain Stenciling or Signage !XI Yes □ No □ N/A Discussion/justification if SC-2 not implemented: SC-3 Protect Outdoor Materials Storage Areas from Rainfall, Run-On, Runoff, and Wind □Yes □ No !XI N/A Dispersal Discussion/justification if SC-3 not implemented: Outdoor material storage areas are not proposed for this project. E-36 Page 1 of 4 Revised 09/16 Source Control Requirement (continued) Applied? SC-4 Protect Materials Stored in Outdoor Work Areas from Rainfall , Run-On, Runoff, and □Yes □ No IX] N/A Wind Dispersal Discussion/justification if SC-4 not implemented: Outdoor work areas not proposed for this project. All work areas will be indoor. SC-5 Protect Trash Storage Areas from Rainfall , Run-On, Runoff, and Wind Dispersal IX] Yes □ No □ N/A Discussion/justification if SC-5 not implemented: SC-6 Additional BMPs based on Potential Sources of Runoff Pollutants must answer for each source listed below and identify additional BMPs. (See Table in Appendix E.1 of BMP Manual for guidance). !xi On-site storm drain inlets IX] Yes □ No □ N/A Ix) Interior floor drains and elevator shaft sump pumps !XI Yes □ No □ N/A □ Interior parking garages □Yes □ No 1X1 N/A IZl Need for future indoor & structural pest control IXI Yes □ No □ N/A IXJ Landscape/Outdoor Pesticide Use !XI Yes □ No □ N/A □ Pools, spas, ponds, decorative fountains, and other water features □Yes □ No 1X1 N/A □ Food service □Yes □ No !XI N/A Ix) Refuse areas IXI Yes □ No □ N/A □ Industrial processes □Yes □ No 1X1 N/A □ Outdoor storage of equipment or materials □Yes □ No 1X1 N/A Ix) Vehicle and Equipment Cleaning ~Yes □ No □ N/A IZl Vehicle/Equipment Repair and Maintenance IX] Yes □ No □ N/A □ Fuel Dispensing Areas □Yes □ No !XI N/A □ Loading Docks □Yes □ No 1X1 N/A Ix) Fire Sprinkler Test Water ~Yes □ No □ N/A IXJ Miscellaneous Drain or Wash Water IXI Yes □ No □ N/A Ix) Plazas, sidewalks, and parking lots ~Yes □ No □ N/A For "Yes" answers, identify the additional BMP Qer AQQendix E.1. Provide justification for "No" answers. -Onsite storm drain inlets will be marked with "NO DUMPING" signs. -Interior floor drains and sum pumps will be plumbed to sanitary sewer. -Landscape areas will be designed to minimize use of fertilizers and pesticides. -Trash enclosure area will be covered and protected form run-on -Vehicle and equipment cleaning is limited to rinsing cars with only water -Parking lots and sidewalks will be swept regularly and debris will be collected prior to entering the storm drain. E-36 Page 2 of 4 Revised 09/16 Site Design BMPs All development projects must implement site design BMPs SD-1 through SD-8 where applicable and feasible. See Chapter 4 and Appendix E.2 thru E.6 of the BMP Design Manual (Volume 5 of City Engineering Standards) for information to implement site design BMPs shown in this checklist. Answer each category below pursuant to the following. • "Yes" means the project will implement the site design BMPs as described in Chapter 4 and/or Appendix E.2 thru E.6 of the Model BMP Design Manual. Discussion/ justification is not required. • "No" means the BMPs is applicable to the project but it is not feasible to implement. Discussion/justification must be provided. Please add attachments if more space is needed. • "N/A" means the BMPs is not applicable at the project site because the project does not include the feature that is addressed by the BMPs (e.g., the project site has no existing natural areas to conserve). Discussion/justification may be provided. Site Design Requirement I Applied? SD-1 Maintain Natural Drainage Pathways and Hydrologic Features I □Yes I □ No I IX! N/A Discussion/justification if SD-1 not implemented: Existing project site has been developed as a commercial center with minimal interior landscaping and no natural drainage pathways or hydrologic features to protect. SD-2 Conserve Natural Areas, Soils, and Vegetation I ~Yes I □ No I □ N/A SD-3 Minimize Impervious Area I IX! Yes I □ No I □ N/A Discussion/justification if SD-3 not implemented: SD-4 Minimize Soil Compaction I IX! Yes I □ No I □ N/A Discussion/justification if SD-4 not implemented: SD-5 Impervious Area Dispersion I IX! Yes I □ No I □ N/A Discussion/justification if SD-5 not implemented: E-36 Page 3 of 4 Revised 09/16 Site Design Requirement (continued) I Applied? SD-6 Runoff Collection I [ZIYes I □ No I □ N/A Discussion/justification if SD-6 not implemented: SD-7 Landscaping with Native or Drought Tolerant Species I IXI Yes I □ No I □ N/A Discussion/justification if SD-7 not implemented: SD-8 Harvesting and Using Precipitation I □Yes I 1X1 No I □ N/A Discussion/justification if SD-8 not implemented: Harvest and Use determined infeasible due to low water usage for commercial site. E-36 Page 4 of 4 Revised 09/16 Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 14 of 27 SUMMARY OF PDP STRUCTURAL BMPS PDP Structural BMPs All PDPs must implement structural BMPs for storm water pollutant control (see Chapter 5 of the BMP Design Manual). Selection of PDP structural BMPs for storm water pollutant control must be based on the selection process described in Chapter 5. PDPs subject to hydromodification management requirements must also implement structural BMPs for flow control for hydromodification management (see Chapter 6 of the BMP Design Manual). Both storm water pollutant control and flow control for hydromodification management can be achieved within the same structural BMP(s). PDP structural BMPs must be verified by the City at the completion of construction. This may include requiring the project owner or project owner's representative to certify construction of the structural BMPs (see Section 1.12 of the BMP Design Manual). PDP structural BMPs must be maintained into perpetuity, and the City must confirm the maintenance (see Section 7 of the BMP Design Manual). Use this form to provide narrative description of the general strategy for structural BMP implementation at the project site in the box below. Then complete the PDP structural BMP summary information sheet for each structural BMP within the project (copy the BMP summary information page as many times as needed to provide summary information for each individual structural BMP). Describe the general strategy for structural BMP implementation at the site. This information must describe how the steps for selecting and designing storm water pollutant control BMPs presented in Section 5.1 of the BMP Design Manual were followed, and the results (type of BMPs selected). For projects requiring hydromodification flow control BMPs, indicate whether pollutant control and flow control BMPs are integrated together or separate. The BMP selection process has been developed in accordance with the new MS4 Permit (R9-2013-0001 as amended by R9-2015-0001 and R9-2015-0100). Harvest and re-use is considered impractical for use on the project site due to it being a proposed commercial area with low water usage. Due to inadequate infiltration rates within the upper 5 feet of site soils and the presence of engineered fill and dense to very dense formation, the project geotechnical engineer concluded that full infiltration is infeasible for the entire project site. Infiltration in any capacity is prohibited adjacent to the western property line or in the northwest property corner due to nearby structures and hillside landscaping. However, partial infiltration is feasible at the northeast and southeast property corners. Therefore, biofiltration areas with partial retention (PR-1) are proposed to treat project flows for pollutant control on the eastern half of the site and lined biofiltration areas (BF-1) are proposed to treat runoff from the western half of the site. Proprietary Biofiltration BMP (BF-3) is proposed for runoff from building roof area due to site layout restrictions due to the nature of a car dealership. Permeable pavers are provided in parking areas east and south of the proposed building to reduce the project site’s total impervious area. The permeable pavers are not considered treatment control BMPs. For DMA-1A and DMA-1B, onsite stormwater will sheetflow to local biofiltration areas with partial retention for treatment and flow control, then routed to the underground detention vault for hydromodification management flow control prior to discharging from the project site. For DMA-1C and DMA-1D, onsite stormwater will sheetflow to local biofiltration areas with impermeable liners for treatment and flow control, then routed to the underground detention vault for hydromodification management flow control prior to discharging from the project site. For DMA-1E, stormwater runoff from rooftop area will be collected at a localized inlet and routed thru BioClean’s Modular Wetland System (MWS) for treatment prior to discharging to the underground detention vaults for hydromodification management flow control. DMA-2A is comprised of self-mitigating landscape area and does not require pollutant control. The hydromodification management for this area is accounted for by the underground detention system (flow control BMP). c:~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 15 of 27 Structural BMP Summary Information Structural BMP ID No. 1 (DMA-1A) DWG: No. 529-6A, Sheets 08 & 11 Type of structural BMP: ☐ Retention by harvest and use (HU-1) ☐ Retention by infiltration basin (INF-1) ☐ Retention by bioretention (INF-2) ☐ Retention by permeable pavement (INF-3) ☒ Partial retention by biofiltration with partial retention (PR-1) ☐ Biofiltration (BF-1) ☐ Flow-thru treatment control included as pre-treatment/forebay for an onsite retention or biofiltration BMP (provide BMP type/description and indicate which onsite retention or biofiltration BMP it serves in discussion section below) ☐ Detention pond or vault for hydromodification management ☐ Other (describe in discussion section below) Purpose: ☐ Pollutant control only ☐ Hydromodification control only ☒ Combined pollutant control and hydromodification control ☐ Pre-treatment/forebay for another structural BMP ☐ Other (describe in discussion section below) Discussion (as needed): Biofiltration area with partial retention is proposed to treat runoff from DMA-1A and provide flow control for the project site’s hydromodification requirement. Geotechnical engineer determined that full infiltration is infeasible for the project site. c:~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 16 of 27 Structural BMP Summary Information Structural BMP ID No. 2 (DMA-1B) DWG: No. 529-6A, Sheets 08 & 11 Type of structural BMP: ☐ Retention by harvest and use (HU-1) ☐ Retention by infiltration basin (INF-1) ☐ Retention by bioretention (INF-2) ☐ Retention by permeable pavement (INF-3) ☒ Partial retention by biofiltration with partial retention (PR-1) ☐ Biofiltration (BF-1) ☐ Flow-thru treatment control included as pre-treatment/forebay for an onsite retention or biofiltration BMP (provide BMP type/description and indicate which onsite retention or biofiltration BMP it serves in discussion section below) ☐ Detention pond or vault for hydromodification management ☐ Other (describe in discussion section below) Purpose: ☐ Pollutant control only ☐ Hydromodification control only ☒ Combined pollutant control and hydromodification control ☐ Pre-treatment/forebay for another structural BMP ☐ Other (describe in discussion section below) Discussion (as needed): Biofiltration basin with partial retention is proposed to treat runoff from DMA-1B and provide flow control for the project site’s hydromodification requirement. Geotechnical engineer determined that full infiltration is infeasible for the project site. c:~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 17 of 27 Structural BMP Summary Information Structural BMP ID No. 3 (DMA-1C) DWG: No. 529-6A, Sheets 08 & 11 Type of structural BMP: ☐ Retention by harvest and use (HU-1) ☐ Retention by infiltration basin (INF-1) ☐ Retention by bioretention (INF-2) ☐ Retention by permeable pavement (INF-3) ☐ Partial retention by biofiltration with partial retention (PR-1) ☒ Biofiltration (BF-1) ☐ Flow-thru treatment control included as pre-treatment/forebay for an onsite retention or biofiltration BMP (provide BMP type/description and indicate which onsite retention or biofiltration BMP it serves in discussion section below) ☐ Detention pond or vault for hydromodification management ☐ Other (describe in discussion section below) Purpose: ☐ Pollutant control only ☐ Hydromodification control only ☒ Combined pollutant control and hydromodification control ☐ Pre-treatment/forebay for another structural BMP ☐ Other (describe in discussion section below) Discussion (as needed): Biofiltration basin with an impermeable liner is proposed to treat runoff from DMA-1C and provide flow control for the project site’s hydromodification requirement. Geotechnical engineer determined that infiltration is infeasible in the project site’s northwest corner. c:~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 18 of 27 Structural BMP Summary Information Structural BMP ID No. 4 (DMA-1D) DWG: No. 529-6A, Sheets 08 & 11 Type of structural BMP: ☐ Retention by harvest and use (HU-1) ☐ Retention by infiltration basin (INF-1) ☐ Retention by bioretention (INF-2) ☐ Retention by permeable pavement (INF-3) ☐ Partial retention by biofiltration with partial retention (PR-1) ☒ Biofiltration (BF-1) ☐ Flow-thru treatment control included as pre-treatment/forebay for an onsite retention or biofiltration BMP (provide BMP type/description and indicate which onsite retention or biofiltration BMP it serves in discussion section below) ☐ Detention pond or vault for hydromodification management ☐ Other (describe in discussion section below) Purpose: ☐ Pollutant control only ☐ Hydromodification control only ☒ Combined pollutant control and hydromodification control ☐ Pre-treatment/forebay for another structural BMP ☐ Other (describe in discussion section below) Discussion (as needed): Biofiltration basin with an impermeable is proposed to treat runoff from DMA-1D and provide flow control for the project site’s hydromodification requirement. Geotechnical engineer determined that infiltration is infeasible along the project site’s western property line. c:~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 19 of 27 Structural BMP Summary Information Structural BMP ID No. 5 (DMA-1E) DWG: No. 529-6A, Sheets 08 & 11 Type of structural BMP: ☐ Retention by harvest and use (HU-1) ☐ Retention by infiltration basin (INF-1) ☐ Retention by bioretention (INF-2) ☐ Retention by permeable pavement (INF-3) ☐ Partial retention by biofiltration with partial retention (PR-1) ☐ Biofiltration (BF-1) ☐ Flow-thru treatment control included as pre-treatment/forebay for an onsite retention or biofiltration BMP (provide BMP type/description and indicate which onsite retention or biofiltration BMP it serves in discussion section below) ☐ Detention pond or vault for hydromodification management ☒ Other (describe in discussion section below) Purpose: ☒ Pollutant control only ☐ Hydromodification control only ☐ Combined pollutant control and hydromodification control ☐ Pre-treatment/forebay for another structural BMP ☐ Other (describe in discussion section below) Discussion (as needed): ☒ Other = Proprietary Biofiltration BMP (BF-3) BioClean Modular Wetland System (MWS) flow-thru device proposed to treat rooftop runoff from DMA-1E. Geotechnical engineer determined that full infiltration is infeasible for the project site. Providing an onsite biofiltration basin for this area would require approximately 1,550 sq-ft, which would reduce the parking count by a total of 10 stalls. Due to the nature of the project site as a car dealership and limited non-hillside landscaping, the use of biofiltration basin for treatment of rooftop runoff is infeasible. c:~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 20 of 27 Structural BMP Summary Information Structural BMP ID No. 6 (all of DMA-1) DWG: No. 529-6A, Sheets 08 & 12 Type of structural BMP: ☐ Retention by harvest and use (HU-1) ☐ Retention by infiltration basin (INF-1) ☐ Retention by bioretention (INF-2) ☐ Retention by permeable pavement (INF-3) ☐ Partial retention by biofiltration with partial retention (PR-1) ☐ Biofiltration (BF-1) ☐ Flow-thru treatment control included as pre-treatment/forebay for an onsite retention or biofiltration BMP (provide BMP type/description and indicate which onsite retention or biofiltration BMP it serves in discussion section below) ☒ Detention pond or vault for hydromodification management ☐ Other (describe in discussion section below) Purpose: ☐ Pollutant control only ☒ Hydromodification control only ☐ Combined pollutant control and hydromodification control ☐ Pre-treatment/forebay for another structural BMP ☐ Other (describe in discussion section below) Discussion (as needed): Proposed underground detention system (solid 8’ dia. CMP by Contech) is proposed for hydromodification management for runoff from entire site. Project site plan shows two vaults (BMP-6A and 6B) that are set at the same invert elevation and hydraulically connected to act as one system. Geotechnical engineer determined that full infiltration is infeasible for the project site. c:~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 21 of 27 ATTACHMENT 1 BACKUP FOR PDP POLLUTANT CONTROL BMPS This is the cover sheet for Attachment 1. Check which Items are Included behind this cover sheet: Attachment Sequence Contents Checklist Attachment 1a DMA Exhibit (Required) See DMA Exhibit Checklist on the back of this Attachment cover sheet. (24”x36” Exhibit typically required) ☑ Included Attachment 1b Tabular Summary of DMAs Showing DMA ID matching DMA Exhibit, DMA Area, and DMA Type (Required)* *Provide table in this Attachment OR on DMA Exhibit in Attachment 1a ☐ Included on DMA Exhibit in Attachment 1a ☑ Included as Attachment 1b, separate from DMA Exhibit Attachment 1c Form I-7, Harvest and Use Feasibility Screening Checklist (Required unless the entire project will use infiltration BMPs) Refer to Appendix B.3-1 of the BMP Design Manual to complete Form I-7. ☑ Included ☐ Not included because the entire project will use infiltration BMPs Attachment 1d Form I-8, Categorization of Infiltration Feasibility Condition (Required unless the project will use harvest and use BMPs) Refer to Appendices C and D of the BMP Design Manual to complete Form I-8. ☑ Included ☐ Not included because the entire project will use harvest and use BMPs Attachment 1e Pollutant Control BMP Design Worksheets / Calculations (Required) Refer to Appendices B and E of the BMP Design Manual for structural pollutant control BMP design guidelines ☑ Included c:~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 22 of 27 Use this checklist to ensure the required information has been included on the DMA Exhibit: The DMA Exhibit must identify: ☑ Underlying hydrologic soil group ☑ Approximate depth to groundwater ☑ Existing natural hydrologic features (watercourses, seeps, springs, wetlands) ☑ Critical coarse sediment yield areas to be protected (if present) ☑ Existing topography and impervious areas ☑ Existing and proposed site drainage network and connections to drainage offsite ☑ Proposed grading ☑ Proposed impervious features ☑ Proposed design features and surface treatments used to minimize imperviousness ☑ Drainage management area (DMA) boundaries, DMA ID numbers, and DMA areas (square footage or acreage), and DMA type (i.e., drains to BMP, self-retaining, or self-mitigating) ☑ Structural BMPs (identify location and type of BMP) c:~Commercial Development Resources ATTACHMENT 1A: DMA EXHIBIT 1, • • t, ~ \ ,•~\ , •-• • :~ 1\1_00~. \ ·• ~- l .. ,i -~ \:\ • .. \ ~' CANN~N ROAD • • ~ C/2 L -• ' • \ ·•: •. •• 11W --\9, c..> \ E::7 --------- • • ?=:' '-----1\' "-v"---. ---"----,9 5"_ "-C/2 ENTIRE SITE ULTIMATELY "~ --~ 1--....___ ~-' \.. -DISCHARGES TO CITY'S ----------SD SYSTEM. I,\ II \9" K -~ ' --POC #1 __,,....__\_,___ll'.'..J'I-ROOF DOWN DRAIN TO BMP-3 ------- > DMA-1 C ,___ _ 1.2 I ~---~---~----,-STRUCTURAL BMP-6B: ~ UNDERGROUND DETENTION SYSTEM FOR ROOF STORM DRAIN SYSTEM PER MEP PLANS I STRUCTURAL BMP-5: ~= PROPRIETARY BIOFILTRATION (BF-3) FOR ------------- S'iOP / • I • • STRUCTURAL BM P-6A: UNDERGROUND DETENTION SYSTEM FOR HYDROMODIFI CATION MANAGEMENT (HYDRAU LICALLY CONNECTED TO BMP-6B) 0 a :11' j ROOF RUNOFF POLLUTANT CONTROL 0 ROOF DOWN --DRAIN TO BMP-5 ROOF STORM DRAIN SYSTEM PER MEP PLANS Ir◊ L t CAR RAMP FLOWS TO DMA-1C 0 ~ ---- ROOF DOWN DRAIN TO BMP-5 0 ---- ROO F STORM DRAIN SYSTEM PER MEP PLANS ( \ I I '&, I d---as --r ~ ~--...--..... 1 ' ,c,I / / / 1.2 )- 0 0 DMA-1 D STRUCTURAL BMP-4: BIOFILTRATION (BF-1) FOR POLLUTANT CONTROL AND HYDROMODIFICATION 0 MANAGEMENT I../ ~--~~--~--- ROOF STORM DRAIN SYSTEM PER MEP PLANS i SD ---- L SD ----SD ---- SD ---- ---- SD ---- HYDROMODIFICATION MANAGEMENT (HYDRAULICALLY CONN ECTED TO BMP-6A) PROPOS ED BUILDING W/ ROOFTOP PARKING ---- +------ 'I ---- LJ ---- ---- ,, ___ _ SD ---- 1.5 1.5 - 1.4 \ ------" 1.5 -., ~ --------- . . . 4_· .• ><·-e·" _;. r\ STRUCTURAL BMP-1 : BIOFILTRATION W/ PARTIAL RETENTION (PR-1 ) FOR POLLUTANT CONTROL AND HYDROMODIFICATION MANAGEMENT SD -----$TI ---- SD SD 103 t ---- LJ STRUCTURAL BMP-2: BIOFILTRATION W/ PARTIAL RETENTION (PR-1 ) FOR POLLUTANT CONTROLAND HYDROMODIFICATION MANAGEM ENT 1.5 - ---- ti\ I I I I \ \ • :~ ~I \ \ : ~ IH+l=id=l---i!./---IJ--I/ 1.5 I I I I I \ ~ \ \ I -=r ) I I I l I \ \ I I LEGEND: ASPHALT (IMPERVIOUS) ----PROPERTY LIN E ' • • CONCRETE (IMPERVIOUS) SURFACE FLOW DIRECTION I I I I I I PERMEABLE PAYERS -SD-PROPOSED STORM DRAIN SYSTEM LANDSCAPE (□MA#) DMA ID ROOF AREA 0 OMA SUB-AREA ID MAJOR OMA BO UNDARY -GD-PROPOSED CONTOUR ----SUB-OMA BOUNDARY -#-EXISTING CONTOUR f I BIOFILTRATI ON BAS IN IW//~I UNDERGROUND DETENTI ON VAULT (W/ PARTIAL RETENTION) liiiw:#w:#~ PROPRIETARY BIOFILTRATION DEVICE BIOFILTRATI ON BAS IN ~I (W/ IMPERMEABLE LINER) PORCELAIN TILE GEOTECHNICAL INFO: • HYDROLOGIC SOIL GROUP B • INFILTRATI ON : 0.041 IN/HR • SOIL EXPANSIVE POTENTIAL: VERY LOW • DEPTH TO GROUNDWATER >50' CCSYAANALYSIS: NO CRITICAL COURSE SEDIMENT YIELD AREAS TO BE PROTECTED BAS ED ON WMAA MAPS. BMP DETAILS: SEE LID BMP DETAILS IN ATTAC HMENT 1 E OF SWOMP. OMA SUMMARY: Post-Develooed Condition OMA Area Area Type ID (SF} (AC} DMA-lA ➔ BIOFILTRATION W/ RETENTION ➔ POC #1 1.1 Roof/Pavement 19,664 0.451 1.2 Landscape (B, 0-5%) 2,314 0.053 1.3 Landscape (B, 5-15%) 520 0.012 1.4 Landscape (B, >15%} 387 0.009 1.5 Permeable Pavers 9,589 0.220 ------·-l: 32,474 0.746 DMA-1B ➔ BIOFILTRATION W/ RETENTION ➔ POC #"1 1.1 Roof/Pavement 8,486 0.195 1.2 Landscape (B, 0-5%) 1,281 0.029 1.3 Landscape (B, 5-15%) 1,030 0.024 1.4 Landscape (B, >15%) 3,765 0.086 LS Permeable Pavers 3,874 0.089 --------------------------------------·-----cc---c'c-ccc··-----------------l: 18,436 0.423 DMA-lC ➔ BIOFILTRATION BASIN ➔ POC #1 1.1 Roof/Pavement 1.2 Landscape (B, 0-5%) 21,181 1,466 L 22,647 OMA-10 ➔ BIOfllTRATION BASIN ➔ POC #1 1.1 Roof/Pavement 13,935 1.2 Landscape (B, 0-5%} 1,117 1.3 Landscape (B, 5-15%) 230 0.486 0.034 0.520 0.320 0.026 0.005 1.5 Permeable Pavers 2,312 0.053 -----------------------------------------------------------------I 17,594 o.404 DMA-lE ➔ PROPRIETARY BIOFILT. (MWS) ➔ POC #1 1.1 Roof/Pavement 57,558 L 57,558 DMA-1 TOTAL 148,710 DMA-2A ➔ SELF-MITIGATING AREA ➔ POC #1 2.1 Roof/Pavement 110 2.2 Landscape (B, 5-15%) 658 1.321 1.321 3.414 0.003 0.015 _____ ?~~-----Landscape~(B_, >_1_5o/c_,) ____ 12_,0 ___ 2s _________ 9~?-~? ___ _ I 12,793 0.294 DMA-2 TOTAL 12,793 0.294 POC #1 TOTAL 161,503 3.708 20 0 20 GRAPHIC SCALE SCALE: 1"= 20' 40 -C 0 E L u 0 --4 I m rn 0 rn ;;- Q_ :, a 3 '" / 4 u ~ 0 ~ m 0 u 31 :, rn, C 0 -0 z -------------------------------------------------------1.s PREPARED FOR: PREPARED BY: " 4, SWQMP ATTACHMENT IA: DMAEXHIBIT + u fr" AU TONATION INC. ;;_ '" 200 SW 1ST STREET, 14TH FLOOR m' FORT LAUDERDALE, FL 33301 Commercial --------------------;~ ~ I CONTACT CLIFF POWELL Development BMW OF CARLSBAD ~ ':11 " • TEL (954) 759 .. 5000 Resources ~- AUTO CENTER CT / / / ' · Today's Ideas Tomorrow's Reality 1060 AUTO CENTER COURT -tJ _j -s=~'"v':. ~ / ··"' 4121 Westerly Place #11 2 Nev11port8eachCA92660 CARLSBAD, CA 92008 t I / 'fP T 949 -610-8997 www.CDRwest.com ~ ~L ___________________________ ....;:..::..::;;;;;;;.;;;;;;........, __________________ ___;1 ____ -'---------';_ _____ ___..~~~--_;_---..l.----------------------...L---------------~~ ATTACHMENT 1B: DMA SUMMARY ATTACHMENT 1b: DMA SUMMARY PROJECT:BMW of Carlsbad LOCATION:Carlsbad, CA DATE:05/21/021 Pre‐Developed Condition Post‐Developed Condition DMA ID Type Area (SF) Area (AC) DMA ID Type Area (SF) Area (AC) DMA‐1A → BIOFILTRATION W/ RETENTION → POC #1 1.1 Natural (B, 0‐5%) 161,503 3.708 1.1 Roof/Pavement 19,664 0.451 ∑161,503 3.708 1.2 Landscape (B, 0‐5%) 2,314 0.053 POC #1 TOTAL 161,503 3.708 1.3 Landscape (B, 5‐15%) 520 0.012 1.4 Landscape (B, >15%) 387 0.009 1.5 Permeable Pavers 9,589 0.220 ∑32,474 0.746 DMA‐1B → BIOFILTRATION W/ RETENTION → POC #1 1.1 Roof/Pavement 8,486 0.195 1.2 Landscape (B, 0‐5%) 1,281 0.029 1.3 Landscape (B, 5‐15%) 1,030 0.024 1.4 Landscape (B, >15%) 3,765 0.086 1.5 Permeable Pavers 3,874 0.089 ∑18,436 0.423 DMA‐1C → BIOFILTRATION BASIN → POC #1 1.1 Roof/Pavement 21,181 0.486 1.2 Landscape (B, 0‐5%) 1,466 0.034 ∑22,647 0.520 DMA‐1D → BIOFILTRATION BASIN → POC #1 1.1 Roof/Pavement 13,935 0.320 1.2 Landscape (B, 0‐5%) 1,117 0.026 1.3 Landscape (B, 5‐15%) 230 0.005 1.5 Permeable Pavers 2,312 0.053 ∑17,594 0.404 DMA‐1E → PROPRIETARY BIOFILT. (MWS) → POC #1 1.1 Roof/Pavement 57,558 1.321 ∑57,558 1.321 DMA‐1 TOTAL 148,710 3.414 DMA‐2A → SELF‐MITIGATING AREA → POC #1 2.1 Roof/Pavement 110 0.003 2.2 Landscape (B, 5‐15%) 658 0.015 2.3 Landscape (B, >15%) 12,025 0.276 ∑12,793 0.294 DMA‐2 TOTAL 12,793 0.294 POC #1 TOTAL 161,503 3.708 DMA‐1 → POC #1 ATTACHMENT 1C: HARVEST AND USE FEASIBILITY CHECKLIST (FORM I‐7) Appendix I: Forms and Checklists I-2 February 2016 Harvest and Use Feasibility Checklist Form I-7 1. Is there a demand for harvested water (check all that apply) at the project site that is reliably present during the wet season? Toilet and urinal flushing Landscape irrigation Other:______________ 2. If there is a demand; estimate the anticipated average wet season demand over a period of 36 hours. Guidance for planning level demand calculations for toilet/urinal flushing and landscape irrigation is provided in Section B.3.2. Toilet Flushing = 7 gal x 100 employees x 1.5 days= 1,050 gal = 140 cf Irrigation = 1,470 gal/ac x 0.569 ac = 836 gal = 112 cf Total 36-Hour Demand = 252 cf 3. Calculate the DCV using worksheet B.2-1. DCV = 5,391 (cubic feet) 3a. Is the 36 hour demand greater than or equal to the DCV? Yes / No 3b. Is the 36 hour demand greater than 0.25DCV but less than the full DCV? Yes / No 3c. Is the 36 hour demand less than 0.25DCV? Yes Harvest and use appears to be feasible. Conduct more detailed evaluation and sizing calculations to confirm that DCV can be used at an adequate rate to meet drawdown criteria. Harvest and use may be feasible. Conduct more detailed evaluation and sizing calculations to determine feasibility. Harvest and use may only be able to be used for a portion of the site, or (optionally) the storage may need to be upsized to meet long term capture targets while draining in longer than 36 hours. Harvest and use is considered to be infeasible. Is harvest and use feasible based on further evaluation? Yes, refer to Appendix E to select and size harvest and use BMPs. No, select alternate BMPs. x x x x x x □ □ □ ATTACHMENT 1D: INFILTRATION FEASIBILITY CHECKLIST (FORM I‐8) Appendix I: Forms and Checklists I-3 February 2016 Categorization of Infiltration Feasibility Condition Form I-8 Part 1 - Full Infiltration Feasibility Screening Criteria Would infiltration of the full design volume be feasible from a physical perspective without any undesirable consequences that cannot be reasonably mitigated? Criteria Screening Question Yes No 1 Is the estimated reliable infiltration rate below proposed facility locations greater than 0.5 inches per hour? The response to this Screening Question shall be based on a comprehensive evaluation of the factors presented in Appendix C.2 and Appendix D. Provide basis: Per the geotechnical investigation report by GMU dated 12/13/19, infiltration rates within the upper 5 feet of site soils were determined to be 0.02 inch/hour and 0.23 inch/hour (not using a factor of safety). Full Infiltration is not feasible at the project site due to the presence of engineered fill and dense to very dense formation. See Geotechnical Investigation Report by GMU attached to this report. Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative discussion of study/data source applicability. 2 Can infiltration greater than 0.5 inches per hour be allowed without increasing risk of geotechnical hazards (slope stability, groundwater mounding, utilities, or other factors) that cannot be mitigated to an acceptable level? The response to this Screening Question shall be based on a comprehensive evaluation of the factors presented in Appendix C.2. Provide basis: N/A Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative discussion of study/data source applicability. X Appendix I: Forms and Checklists I-4 February 2016 Form I-8 Page 2 of 4 Criteri a Screening Question Yes No 3 Can infiltration greater than 0.5 inches per hour be allowed without increasing risk of groundwater contamination (shallow water table, storm water pollutants or other factors) that cannot be mitigated to an acceptable level? The response to this Screening Question shall be based on a comprehensive evaluation of the factors presented in Appendix C.3. Provide basis: N/A Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative discussion of study/data source applicability. 4 Can infiltration greater than 0.5 inches per hour be allowed without causing potential water balance issues such as change of seasonality of ephemeral streams or increased discharge of contaminated groundwater to surface waters? The response to this Screening Question shall be based on a comprehensive evaluation of the factors presented in Appendix C.3. Provide basis: N/A Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative discussion of study/data source applicability. Part 1 Result * If all answers to rows 1 - 4 are “Yes” a full infiltration design is potentially feasible. The feasibility screening category is Full Infiltration If any answer from row 1-4 is “No”, infiltration may be possible to some extent but would not generally be feasible or desirable to achieve a “full infiltration” design. Proceed to Part 2 *To be completed using gathered site information and best professional judgment considering the definition of MEP in the MS4 Permit. Additional testing and/or studies may be required by the City to substantiate findings. Appendix I: Forms and Checklists I-5 February 2016 Form I-8 Page 3 of 4 Part 2 – Partial Infiltration vs. No Infiltration Feasibility Screening Criteria Would infiltration of water in any appreciable amount be physically feasible without any negative consequences that cannot be reasonably mitigated? Criteria Screening Question Yes No 5 Do soil and geologic conditions allow for infiltration in any appreciable rate or volume? The response to this Screening Question shall be based on a comprehensive evaluation of the factors presented in Appendix C.2 and Appendix D. Provide basis: Per the geotechnical investigation report by GMU dated 12/13/19, infiltration rates within the upper 5 feet of site soils were determined to be 0.02 inch/hour and 0.23 inch/hour (unfactored). Full infiltration is not feasible at the project site due to the presence of engineered fill and dense to very dense formation. See Geotechnical Investigation Report by GMU attached to this report. An averaged infiltration rate of 0.041 in/hr (with factor of safety = 3) is used for partial infiltration. Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative discussion of study/data source applicability and why it was not feasible to mitigate low infiltration rates. 6 Can Infiltration in any appreciable quantity be allowed without increasing risk of geotechnical hazards (slope stability, groundwater mounding, utilities, or other factors) that cannot be mitigated to an acceptable level? The response to this Screening Question shall be based on a comprehensive evaluation of the factors presented in Appendix C.2. Provide basis: N/A Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative discussion of study/data source applicability and why it was not feasible to mitigate low infiltration rates. X X Appendix I: Forms and Checklists I-6 February 2016 Form I-8 Page 4 of 4 Criteria Screening Question Yes No 7 Can Infiltration in any appreciable quantity be allowed without posing significant risk for groundwater related concerns (shallow water table, storm water pollutants or other factors)? The response to this Screening Question shall be based on a comprehensive evaluation of the factors presented in Appendix C.3. Provide basis: N/A Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative discussion of study/data source applicability and why it was not feasible to mitigate low infiltration rates. 8 Can infiltration be allowed without violating downstream water rights? The response to this Screening Question shall be based on a comprehensive evaluation of the factors presented in Appendix C.3. Provide basis: N/A Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative discussion of study/data source applicability and why it was not feasible to mitigate low infiltration rates. Part 2 Result* If all answers from row 5-8 are yes then partial infiltration design is potentially feasible. The feasibility screening category is Partial Infiltration. If any answer from row 5-8 is no, then infiltration of any volume is considered to be infeasible within the drainage area. The feasibility screening category is No Infiltration. *To be completed using gathered site information and best professional judgment considering the definition of MEP in the MS4 Permit. Additional testing and/or studies may be required by the City to substantiate findings. X X May 20, 2021 Axay Patel Autonation 200 SW 1st Street, 14th Floor Ft. Lauderdale, FL, 33301 GMU Project 18-101-00 Subject: Partial Infiltration of Unlined Biofiltration Basins References: Geotechnical Investigation Report, Auto Nation BMW of Carlsbad, 1050 and 1060 Auto Center Court, Carlsbad, California Dear Mr. Patel: Per our referenced geotechnical report two preliminary infiltration tests were completed in general accordance with the San Diego Low Impact Development (LID) handbook. These tests were completed at approximately 5 feet below grade. The results presented in our report do not incorporate a factor of safety. The unfactored rates are 0.02 inches per hour and 0.23 inches per hour for drill hole locations 6 and 7, respectively. See our referenced report for these drill hole locations within the site. Although “infiltration” was determined not to be feasible, it is our opinion that partial infiltration may be considered from a geotechnical perspective for the (2) site unlined biofiltration basins given that some infiltration was recorded. provided the following: 1. The infiltration rates contained in our referenced report be utilized for design. How the rates are utilized in the design shall be solely per the basin designer – i.e. project civil engineer or hydromodification consultant. 2. There is an overflow outlet incorporated in the design. 3. Our specifications for the permeable concrete interlocking vehicular pavers with respect to subgrade preparation are adapted to the unlined biofiltration basins where partial infiltration is desired. Respectfully submitted, Matthew T. Farrington M.Sc., PE 90349 Project Engineer Distribution: Aaron Alberts, CDR 23241 Arroyo Vista Rancho Santa Margarita I CA 92688 949.888.6513 I FX: 949.888.1380 I www.gmugeo.com Appendix I: Forms and Checklists I-7 February 2016 Factor of Safety and Design Infiltration Rate Worksheet Form I-9 Factor Category Factor Description Assigned Weight (w) Factor Value (v) Product (p) p = w x v A Suitability Assessment Soil assessment methods 0.25 Predominant soil texture 0.25 Site soil variability 0.25 Depth to groundwater / impervious layer 0.25 Suitability Assessment Safety Factor, SA = 6p B Design Level of pretreatment/ expected sediment loads 0.5 Redundancy/resiliency 0.25 Compaction during construction 0.25 Design Safety Factor, SB = 6p Combined Safety Factor, Stotal= SA x SB Observed Infiltration Rate, inch/hr, Kobserved (corrected for test-specific bias) Design Infiltration Rate, in/hr, Kdesign = Kobserved / Stotal Supporting Data Briefly describe infiltration test and provide reference to test forms: Per geotechnical report by GMU dated 12/13/19: "Two (2) preliminary infiltration tests were performed in general conformance with the County of San Diego Low Impact Development (LID) Handbook. The infiltration drill holes were excavated to depths ranging from 4 to 5 feet below the existing grade using a hollow-stem-auger, truck-mounted drill rig." The calculated unfactored infiltration rates are 0.02 in/hr at 5.0' bgs and 0.23 in/hr at 4.0' bgs. 0.02 + 0.23 = 0.125 2 3.0 0.041 in/hr 1 1 3 2 0.50 0.75 0.25 0.25 1.75 1 2 1 0.25 0.50 0.50 1.25 ATTACHMENT 1E: POLLUTANT CONTROL BMP DESIGN WORKSHEETS / CALCULATIONS PROJECT:BMW of Carlsbad LOCATION:Carlsbad, CA DATE:05/21/2021 Per Appendix B of the City of Carlsbad BMP Design Manual:NOTES: DCV = 3,630 X C X d x A 1. Impervious → Roof/Pavement [Cx=0.90] Q =C X i X A 2. Pervious → Landscape (B), Permeable Pavers [Cx=0.10] DCV = Design Capture Volume (cf)3. DCV result used for City Worksheets B.4‐1 & B.5‐1 Q = Diversion flow rate (cfs) for offline BMP C =Adjusted runoff factor (unitless) = (∑C xAx /∑A x) d =85thpercentile, 24‐hr storm event rainfall depth (in) =0.58 A = Tributary area to BMP (ac) i = Rainfall intensity = 0.2 in/hr [3% of A*C] ∑CXAX ∑AX Biofiltration Basin w/ Partial Retention → POC #1 1A 32,474 0.746 19,664 12,810 60.6% 39.4% 917 569 0.087 1B 18,436 0.423 8,486 9,951 46.0% 54.0% 417 259 0.040 50,911 1.169 28,149 22,761 55.3% 44.7% 1,335 Biofiltration Basin w/ Impermeable Liner → POC #1 1C 22,647 0.520 21,181 1,466 93.5% 6.5% 928 576 0.088 1D 17,594 0.404 13,935 3,659 79.2% 20.8% 624 387 0.059 40,241 0.924 35,116 5,125 87.3% 12.7% 1,552 Proprietary Biofiltration (MWS) → POC #1 2A 57,558 1.321 57,558 0 100.0% 0.0% 2,504 1,554 0.238 57,558 1.321 57,558 0 100.0% 0.0%2,504 Self‐Mitigating Areas → POC #1 2A 12,793 0.294 110 12,682 0.9% 99.1%‐‐‐‐‐‐ ‐‐‐ 12,793 0.294 110 12,682 0.9% 99.1%‐‐‐ TOTAL 161,503 3.708 120,934 40,568 74.9% 25.1% 5,391 3,387 ATTACHMENT 1e: LID DESIGN CAPTURE VOLUME (DCV) CALCULATIONS 0.848 0.734 0.900 ‐‐‐ 0.699 QReq. (CFS) 0.584 0.468 DMA ID Area, A (SF) Area, A (AC)Ai (SF) AP (SF) Ai (%) AP (%)C =DCV (CF) Minimum Footprint (SF) Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods B-5 February 2016 Figure B.1-1: 85th Percentile 24-hour Isopluvial Map San Diego County 85 th Percentile lsopluvials Legend --85th PERCENTILE ISOPLUVIAL c·~-~-_J INCORPORATED CITY NOTE: The 85th percentile is a 24 hour rainfall total. It represetns a value such that 85% of the observed 24 hour rainfall totals will be less than that value. N + ~Milts 0 1 2 15 8 THIS""""~Tll~Pff:CNIOED....,IHOtlfWI\.RAANTYOf'MYKIN0.ElfttER E1J>R!:SS~IMPLEO,INO..L0HOMNOTUMITEOTO TltEIMPLlfD WlRFIANTll;&0F111€1'1CH,t,NT.481UfVJ,NO,!TN€88'0MAPII.RTICULAA PV!!f"06E NOii P•l>'QIMl""YOOl'IIMl~ICl'lflOl'llhSO,ND,t,G R,,Q ...... lnkmlalons,,_,. __ ._-"""'""'''"""' ... ll'le"'lbn -OISANO,O,G l,_Pf!OCIUC!t'l.,_...,nwo,,.._,__.,...,, -~11¥R¥o!M~-~1DS,,,OIS l~rafCI• <OPJ"'011acl1>yR-11c:Na11jo&O:,r,,i,~l■W1....tu!bccv,,0<all0<....,.P911'1e"°'-fo,p,1--or .... w4houtit._,_,_ --OI-M<tllfty&C:O,,,p,11'1!'9 Olo,rt,11SanGJSX111 .-...~~ rl.llllH11X1'N_. __ tle --.n"'J-u,,g,aOf'l>'lagal __ Mm ~"'201~ P,,-l:lt)deo,,..otoNO,V,_ATl.All_l•FCTSS_R!;Vl!IITED_201!!11, IPCTSS.OISl'I.AY!U<I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods B-26 February 2016 Worksheet B.5-1: Simple Sizing Method for Biofiltration BMPs Simple Sizing Method for Biofiltration BMPs Worksheet B.5-1 1 Remaining DCV after implementing retention BMPs cubic-feet Partial Retention 2 Infiltration rate from Form I-9 if partial infiltration is feasible in/hr. 3 Allowable drawdown time for aggregate storage below the underdrain 36 hours 4 Depth of runoff that can be infiltrated [Line 2 x Line 3] inches 5 Aggregate pore space 0.40 in/in 6 Required depth of gravel below the underdrain [Line 4/ Line 5] inches 7 Assumed surface area of the biofiltration BMP sq-ft 8 Media retained pore storage 0.1 in/in 9 Volume retained by BMP [[Line 4 + (Line 12 x Line 8)]/12] x Line 7 cubic-feet 10 DCV that requires biofiltration [Line 1 – Line 9] cubic-feet BMP Parameters 11 Surface Ponding [6 inch minimum, 12 inch maximum] inches 12 Media Thickness [18 inches minimum], also add mulch layer thickness to this line for sizing calculations inches 13 Aggregate Storage above underdrain invert (12 inches typical) – use 0 inches for sizing if the aggregate is not over the entire bottom surface area 1 inches 14 Media available pore space 0.2 in/in 15 Media filtration rate to be used for sizing (5 in/hr. with no outlet control; if the filtration is controlled by the outlet, use the outlet controlled rate) 5 in/hr. Baseline Calculations 16 Allowable Routing Time for sizing 6 hours 17 Depth filtered during storm [ Line 15 x Line 16] 30 inches 18 Depth of Detention Storage [Line 11 + (Line 12 x Line 14) + (Line 13 x Line 5)] inches 19 Total Depth Treated [Line 17 + Line 18] inches Option 1 – Biofilter 1.5 times the DCV 20 Required biofiltered volume [1.5 x Line 10] cubic-feet 21 Required Footprint [Line 20/ Line 19] x 12 sq-ft Option 2 - Store 0.75 of remaining DCV in pores and ponding 22 Required Storage (surface + pores) Volume [0.75 x Line 10] cubic-feet 23 Required Footprint [Line 22/ Line 18] x 12 sq-ft Footprint of the BMP 24 Area draining to the BMP sq-ft 25 Adjusted Runoff Factor for drainage area (Refer to Appendix B.1 and B.2) 26 Minimum BMP Footprint [Line 24 x Line 25 x 0.03] sq-ft 27 Footprint of the BMP = Maximum(Minimum(Line 21, Line 23), Line 26) sq-ft Note: Line 7 is used to estimate the amount of volume retained by the BMP. Update assumed surface area in Line 7 until its equivalent to the required biofiltration footprint (either Line 21 or Line 23) 917 0.041 1.48 3.69 812 6 18+3=21 3 12.6 42.6 242 675 1,013 285 506 482 32,474 0.584 569 569 I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods B-26 February 2016 Worksheet B.5-1: Simple Sizing Method for Biofiltration BMPs Simple Sizing Method for Biofiltration BMPs Worksheet B.5-1 1 Remaining DCV after implementing retention BMPs cubic-feet Partial Retention 2 Infiltration rate from Form I-9 if partial infiltration is feasible in/hr. 3 Allowable drawdown time for aggregate storage below the underdrain 36 hours 4 Depth of runoff that can be infiltrated [Line 2 x Line 3] inches 5 Aggregate pore space 0.40 in/in 6 Required depth of gravel below the underdrain [Line 4/ Line 5] inches 7 Assumed surface area of the biofiltration BMP sq-ft 8 Media retained pore storage 0.1 in/in 9 Volume retained by BMP [[Line 4 + (Line 12 x Line 8)]/12] x Line 7 cubic-feet 10 DCV that requires biofiltration [Line 1 – Line 9] cubic-feet BMP Parameters 11 Surface Ponding [6 inch minimum, 12 inch maximum] inches 12 Media Thickness [18 inches minimum], also add mulch layer thickness to this line for sizing calculations inches 13 Aggregate Storage above underdrain invert (12 inches typical) – use 0 inches for sizing if the aggregate is not over the entire bottom surface area 1 inches 14 Media available pore space 0.2 in/in 15 Media filtration rate to be used for sizing (5 in/hr. with no outlet control; if the filtration is controlled by the outlet, use the outlet controlled rate) 5 in/hr. Baseline Calculations 16 Allowable Routing Time for sizing 6 hours 17 Depth filtered during storm [ Line 15 x Line 16] 30 inches 18 Depth of Detention Storage [Line 11 + (Line 12 x Line 14) + (Line 13 x Line 5)] inches 19 Total Depth Treated [Line 17 + Line 18] inches Option 1 – Biofilter 1.5 times the DCV 20 Required biofiltered volume [1.5 x Line 10] cubic-feet 21 Required Footprint [Line 20/ Line 19] x 12 sq-ft Option 2 - Store 0.75 of remaining DCV in pores and ponding 22 Required Storage (surface + pores) Volume [0.75 x Line 10] cubic-feet 23 Required Footprint [Line 22/ Line 18] x 12 sq-ft Footprint of the BMP 24 Area draining to the BMP sq-ft 25 Adjusted Runoff Factor for drainage area (Refer to Appendix B.1 and B.2) 26 Minimum BMP Footprint [Line 24 x Line 25 x 0.03] sq-ft 27 Footprint of the BMP = Maximum(Minimum(Line 21, Line 23), Line 26) sq-ft Note: Line 7 is used to estimate the amount of volume retained by the BMP. Update assumed surface area in Line 7 until its equivalent to the required biofiltration footprint (either Line 21 or Line 23) 417 0.041 1.48 3.69 359 6 18+3=21 6 12.6 42.6 107 310 465 135 233 222 18,436 0.468 259 259 I 78" DIA. OPENING FLOW CONTROL ORIFICE PLATE HOT-DIP GALVANIZED PLATE GREATER THAN UNDERDRAIN W/ DRILLED HOLE INVERT OF 6" DIA. SLOTTED PVC UNDERDRAIN = BOTTOM OF BASIN RISER WALL FLOW CONTROL ORIFICE PLATE, SEE DETAIL ABOVE 6" DIA. SLOTTED PVC UNDERDRAIN 4" 78" DIA. ORIFICE 4" NATURAL SOIL FILTER & GRAVEL STORAGE BOTTOM OF BASIN CLEAN OUT (C.O.) DETAIL 9" 6" PVC SCREW CAP FINISH GRADE WATERTIGHT CAP ON TERMINAL END OF PIPE 6" DIA. SLOTTED PVC UNDERDRAIN CONNECTED TO DOWNSTREAM CLEANOUT OR SQUARE RISER MULCH 7" GRAVEL (STORAGE) 18" AMENDED SOIL 3" MULCH 6" PONDING 6" FREEBOARD VARIES PER PLAN RETAINING WALL RETAINING WALL 3'x3' RISER (2'x2' INTERNALLY) OUTLET PIPE PER PLAN 3.33' 3" PEA GRAVEL (FILTER) 3" SAND (FILTER) NOTE: SLOTTED UNDERDRAIN AND ORIFICE OUTLET NOT SHOWN 6" DIA. SLOTTED PVC UNDERDRAIN NATURAL SOIL GRAVEL STORAGE AMENDED SOIL MEDIA FILTER COURSE 3" PEA GRAVEL 6" 3" SAND 1" BOTTOM OF BASIN 6" DIA. SLOTTED PVC UNDERDRAIN ORIFICE PLATE TOP GRATE OUTFALL PIPE, SIZE & LOCATION PER PLAN NOTE: UNDERDRAIN ENTERS RISER AT ONLY 1 (ONE) SIDE. BMP-2 BMP-1 HORIZONTAL 6" DIA. SLOTTED PVC UNDERDRAIN HORIZONTAL 6" DIA. SLOTTED PVC UNDERDRAIN HORIZONTAL 6" DIA. SLOTTED PVC UNDERDRAIN BMP-1 RISER BMP-2 RISER C.O. C.O. BMP-1 & BMP-2: UNDERDRAIN & RISER OUTLET LOCATION DETAIL (N.T.S.) BMW OF CARLSBAD 1060 AUTO CENTER COURT CARLSBAD, CA 92008 LID DETAILS: BMP-1 & BMP-2 BMP RISER OUTLET DETAIL (N.T.S.) CLEAN OUT (C.O.) DETAIL (N.T.S.) BMP-1 & BMP-2: BASIN CROSS-SECTION (TYP.) (N.T.S.) BIOFILTRATION W/ PARTIAL RETENTION BMP-1 & BMP-2: LID ORIFICE DETAIL (N.T.S.) BMP-1 & BMP-2: PLACEMENT OF UNDERDRAIN DETAIL (N.T.S.) I / / / I-/ {v-,z>, •:. -- \ 4 I . 8 h .., ~ o I O 0 0 0 / C~Commercial Development Resources Today's Ideas. Tomorrow's Reality. 412·1 WE'ster1\I' Place #1 12 r.Jewport 8Mch CA. 92650 T 949---610-8997 V<NiW CDRw,;,st com ~ I r ~ 4 ./ L'.I <I . I} p <I . 4 - i LC Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods B-26 February 2016 Worksheet B.5-1: Simple Sizing Method for Biofiltration BMPs Simple Sizing Method for Biofiltration BMPs Worksheet B.5-1 1 Remaining DCV after implementing retention BMPs cubic-feet Partial Retention 2 Infiltration rate from Form I-9 if partial infiltration is feasible in/hr. 3 Allowable drawdown time for aggregate storage below the underdrain 36 hours 4 Depth of runoff that can be infiltrated [Line 2 x Line 3] inches 5 Aggregate pore space 0.40 in/in 6 Required depth of gravel below the underdrain [Line 4/ Line 5] inches 7 Assumed surface area of the biofiltration BMP sq-ft 8 Media retained pore storage 0.1 in/in 9 Volume retained by BMP [[Line 4 + (Line 12 x Line 8)]/12] x Line 7 cubic-feet 10 DCV that requires biofiltration [Line 1 – Line 9] cubic-feet BMP Parameters 11 Surface Ponding [6 inch minimum, 12 inch maximum] inches 12 Media Thickness [18 inches minimum], also add mulch layer thickness to this line for sizing calculations inches 13 Aggregate Storage above underdrain invert (12 inches typical) – use 0 inches for sizing if the aggregate is not over the entire bottom surface area 1 inches 14 Media available pore space 0.2 in/in 15 Media filtration rate to be used for sizing (5 in/hr. with no outlet control; if the filtration is controlled by the outlet, use the outlet controlled rate) 5 in/hr. Baseline Calculations 16 Allowable Routing Time for sizing 6 hours 17 Depth filtered during storm [ Line 15 x Line 16] 30 inches 18 Depth of Detention Storage [Line 11 + (Line 12 x Line 14) + (Line 13 x Line 5)] inches 19 Total Depth Treated [Line 17 + Line 18] inches Option 1 – Biofilter 1.5 times the DCV 20 Required biofiltered volume [1.5 x Line 10] cubic-feet 21 Required Footprint [Line 20/ Line 19] x 12 sq-ft Option 2 - Store 0.75 of remaining DCV in pores and ponding 22 Required Storage (surface + pores) Volume [0.75 x Line 10] cubic-feet 23 Required Footprint [Line 22/ Line 18] x 12 sq-ft Footprint of the BMP 24 Area draining to the BMP sq-ft 25 Adjusted Runoff Factor for drainage area (Refer to Appendix B.1 and B.2) 26 Minimum BMP Footprint [Line 24 x Line 25 x 0.03] sq-ft 27 Footprint of the BMP = Maximum(Minimum(Line 21, Line 23), Line 26) sq-ft Note: Line 7 is used to estimate the amount of volume retained by the BMP. Update assumed surface area in Line 7 until its equivalent to the required biofiltration footprint (either Line 21 or Line 23) 928 0 0 0 576 6 18+3=21 6 12.6 42.6 101 828 1,241 350 621 591 22,647 0.848 576 576 I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods B-26 February 2016 Worksheet B.5-1: Simple Sizing Method for Biofiltration BMPs Simple Sizing Method for Biofiltration BMPs Worksheet B.5-1 1 Remaining DCV after implementing retention BMPs cubic-feet Partial Retention 2 Infiltration rate from Form I-9 if partial infiltration is feasible in/hr. 3 Allowable drawdown time for aggregate storage below the underdrain 36 hours 4 Depth of runoff that can be infiltrated [Line 2 x Line 3] inches 5 Aggregate pore space 0.40 in/in 6 Required depth of gravel below the underdrain [Line 4/ Line 5] inches 7 Assumed surface area of the biofiltration BMP sq-ft 8 Media retained pore storage 0.1 in/in 9 Volume retained by BMP [[Line 4 + (Line 12 x Line 8)]/12] x Line 7 cubic-feet 10 DCV that requires biofiltration [Line 1 – Line 9] cubic-feet BMP Parameters 11 Surface Ponding [6 inch minimum, 12 inch maximum] inches 12 Media Thickness [18 inches minimum], also add mulch layer thickness to this line for sizing calculations inches 13 Aggregate Storage above underdrain invert (12 inches typical) – use 0 inches for sizing if the aggregate is not over the entire bottom surface area 1 inches 14 Media available pore space 0.2 in/in 15 Media filtration rate to be used for sizing (5 in/hr. with no outlet control; if the filtration is controlled by the outlet, use the outlet controlled rate) 5 in/hr. Baseline Calculations 16 Allowable Routing Time for sizing 6 hours 17 Depth filtered during storm [ Line 15 x Line 16] 30 inches 18 Depth of Detention Storage [Line 11 + (Line 12 x Line 14) + (Line 13 x Line 5)] inches 19 Total Depth Treated [Line 17 + Line 18] inches Option 1 – Biofilter 1.5 times the DCV 20 Required biofiltered volume [1.5 x Line 10] cubic-feet 21 Required Footprint [Line 20/ Line 19] x 12 sq-ft Option 2 - Store 0.75 of remaining DCV in pores and ponding 22 Required Storage (surface + pores) Volume [0.75 x Line 10] cubic-feet 23 Required Footprint [Line 22/ Line 18] x 12 sq-ft Footprint of the BMP 24 Area draining to the BMP sq-ft 25 Adjusted Runoff Factor for drainage area (Refer to Appendix B.1 and B.2) 26 Minimum BMP Footprint [Line 24 x Line 25 x 0.03] sq-ft 27 Footprint of the BMP = Maximum(Minimum(Line 21, Line 23), Line 26) sq-ft Note: Line 7 is used to estimate the amount of volume retained by the BMP. Update assumed surface area in Line 7 until its equivalent to the required biofiltration footprint (either Line 21 or Line 23) 624 0 0 0 455 6 18+3=21 6 12.6 42.6 80 544 816 230 408 389 17,594 0.734 387 387 I NOTE: UNDERDRAIN ENTERS RISER AT ONLY 1 (ONE) SIDE. BMP-4 BMP-2 BMP-1 BMP-3 HORIZONTAL 6" DIA. SLOTTED PVC UNDERDRAIN BMP-4 RISER HORIZONTAL 6" DIA. SLOTTED PVC UNDERDRAIN HORIZONTAL 6" DIA. SLOTTED PVC UNDERDRAIN HORIZONTAL 6" DIA. SLOTTED PVC UNDERDRAIN BMP-1 RISER BMP-3 RISER BMP-2 RISER C.O. C.O. C.O. C.O. 6" GRAVEL (STORAGE) 18" AMENDED SOIL 3" MULCH 6" PONDING 6" FREEBOARD VARIES PER PLAN RETAINING WALL RETAINING WALL 3'x3' RISER (2'x2' INTERNALLY) OUTLET PIPE IMPERMEABLE LINER, SEE NOTES 3.25' NOTE: 1. SLOTTED UNDERDRAIN AND ORIFICE OUTLET NOT SHOWN 2. IMPERMEABLE LINER TO BE 30 MIL GSE HD SMOOTH LINER FROM GSE ENVIRONMENTAL OR APPROVED EQUIVALENT 3" PEA GRAVEL (FILTER) 3" SAND (FILTER) CLEAN OUT (C.O.) DETAIL 9" 6" PVC SCREW CAP FINISH GRADE WATERTIGHT CAP ON TERMINAL END OF PIPE 6" DIA. SLOTTED PVC UNDERDRAIN CONNECTED TO DOWNSTREAM CLEANOUT OR SQUARE RISER MULCH 6" DIA. SLOTTED PVC UNDERDRAIN ORIFICE PLATE TOP GRATE OUTFALL PIPE, SIZE & LOCATION PER PLAN BMP-4 6" DIA. SLOTTED PVC UNDERDRAIN GRAVEL STORAGE FILTER COURSE IMPERMEABLE LINER AT BOTTOM OF BASIN TO BE 30 MIL GSE HD SMOOTH LINER BY GSE ENVIRONMENTAL OR APPROVED EQUIVALENT NATURAL SOIL AMENDED SOIL MEDIA 3" PEA GRAVEL 6" 3" SAND 34" DIA. OPENING FLOW CONTROL ORIFICE PLATE HOT-DIP GALVANIZED PLATE GREATER THAN UNDERDRAIN W/ DRILLED HOLE INVERT OF 6" DIA. SLOTTED PVC UNDERDRAIN = BOTTOM OF BASIN RISER WALL FLOW CONTROL ORIFICE PLATE, SEE DETAIL ABOVE 6" DIA. SLOTTED PVC UNDERDRAIN 3" 34" DIA. ORIFICE 3" NATURAL SOIL FILTER & GRAVEL STORAGE BOTTOM OF BASIN W/ IMPERMEABLE LINER BMP-3 & BMP-4: LID ORIFICE DETAIL BMP-3 & BMP-4: UNDERDRAIN & RISER OUTLET LOCATION DETAIL (N.T.S.) BMW OF CARLSBAD 1060 AUTO CENTER COURT CARLSBAD, CA 92008 LID DETAILS: BMP-3 & BMP-4 BMP RISER OUTLET DETAIL (N.T.S.) CLEAN OUT (C.O.) DETAIL (N.T.S.) BMP-3 & BMP-4: BASIN CROSS-SECTION (TYP.) (N.T.S.) BIOFILTRATION BASIN BMP-3 & BMP-4: LID ORIFICE DETAIL (N.T.S.) BMP-3 & BMP-4: PLACEMENT OF UNDERDRAIN DETAIL (N.T.S.) I ---- I- Ll <l . --------\ ·. l c O ~ o -l o o § I . < 0 0 ° ~ -~1(<lll _u_1•~+'--'-'~r. <l . p 4 4 L._c__---t-----+--~ _____ ./ C~Commercial Development Resources Today's Ideas. Tomorrow's Reality. 412·1 WE'ster1\I' Place #1 12 r.Jewport 8Mch CA. 92650 T 949---610-8997 V<NiW CDRw,;,st com Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods B-26 February 2016 Worksheet B.5-1: Simple Sizing Method for Biofiltration BMPs Simple Sizing Method for Biofiltration BMPs Worksheet B.5-1 1 Remaining DCV after implementing retention BMPs cubic-feet Partial Retention 2 Infiltration rate from Form I-9 if partial infiltration is feasible in/hr. 3 Allowable drawdown time for aggregate storage below the underdrain 36 hours 4 Depth of runoff that can be infiltrated [Line 2 x Line 3] inches 5 Aggregate pore space 0.40 in/in 6 Required depth of gravel below the underdrain [Line 4/ Line 5] inches 7 Assumed surface area of the biofiltration BMP sq-ft 8 Media retained pore storage 0.1 in/in 9 Volume retained by BMP [[Line 4 + (Line 12 x Line 8)]/12] x Line 7 cubic-feet 10 DCV that requires biofiltration [Line 1 – Line 9] cubic-feet BMP Parameters 11 Surface Ponding [6 inch minimum, 12 inch maximum] inches 12 Media Thickness [18 inches minimum], also add mulch layer thickness to this line for sizing calculations inches 13 Aggregate Storage above underdrain invert (12 inches typical) – use 0 inches for sizing if the aggregate is not over the entire bottom surface area 1 inches 14 Media available pore space 0.2 in/in 15 Media filtration rate to be used for sizing (5 in/hr. with no outlet control; if the filtration is controlled by the outlet, use the outlet controlled rate) 5 in/hr. Baseline Calculations 16 Allowable Routing Time for sizing 6 hours 17 Depth filtered during storm [ Line 15 x Line 16] 30 inches 18 Depth of Detention Storage [Line 11 + (Line 12 x Line 14) + (Line 13 x Line 5)] inches 19 Total Depth Treated [Line 17 + Line 18] inches Option 1 – Biofilter 1.5 times the DCV 20 Required biofiltered volume [1.5 x Line 10] cubic-feet 21 Required Footprint [Line 20/ Line 19] x 12 sq-ft Option 2 - Store 0.75 of remaining DCV in pores and ponding 22 Required Storage (surface + pores) Volume [0.75 x Line 10] cubic-feet 23 Required Footprint [Line 22/ Line 18] x 12 sq-ft Footprint of the BMP 24 Area draining to the BMP sq-ft 25 Adjusted Runoff Factor for drainage area (Refer to Appendix B.1 and B.2) 26 Minimum BMP Footprint [Line 24 x Line 25 x 0.03] sq-ft 27 Footprint of the BMP = Maximum(Minimum(Line 21, Line 23), Line 26) sq-ft Note: Line 7 is used to estimate the amount of volume retained by the BMP. Update assumed surface area in Line 7 until its equivalent to the required biofiltration footprint (either Line 21 or Line 23) 2,504 0 0 0 1,554 6 18+3=21 9 13.8 43.8 0 2,504 3,756 1,029 1,878 1,633 57,558 0.90 1,554 1,554 I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods B-36 February 2016 B.6.3 Sizing Flow-Thru Treatment Control BMPs: Use for Sizing Proprietary Biofiltration BMP Flow-thru treatment control BMPs shall be sized to filter or treat the maximum flow rate of runoff produced from a rainfall intensity of 0.2 inch of rainfall per hour, for each hour of every storm event. The required flow-thru treatment rate should be adjusted for the portion of the DCV already retained or biofiltered onsite as described in Worksheet B.6-1. The following hydrologic method shall be used to calculate the flow rate to be filtered or treated: ܳൌܥൈ݅ൈܣ Where: Q = Design flow rate in cubic feet per second C = Runoff factor, area-weighted estimate using Table B.1-1. i = Rainfall intensity of 0.2 in/hr. A = Tributary area (acres) which includes the total area draining to the BMP, including any offsite or onsite areas that comingle with project runoff and drain to the BMP. Refer to Section 3.3.3 for additional guidance. Street projects consult Section 1.4.2. Worksheet B.6-1: Flow-Thru Design Flows Flow-thru Design Flows Worksheet B.6-1 1 DCV DCV cubic-feet 2 DCV retained DCVretained cubic-feet 3 DCV biofiltered DCVbiofiltered cubic-feet 4 DCV requiring flow-thru (Line 1 – Line 2 – 0.67xLine 3) DCVflow-thru cubic-feet 5 Adjustment factor (Line 4 / Line 1)* AF= unitless 6 Design rainfall intensity i= 0.20 in/hr 7 Area tributary to BMP (s) A= acres 8 Area-weighted runoff factor (estimate using Appendix B.2) C= unitless 9 Calculate Flow Rate = AF x (C x i x A) Q= cfs *Adjustment factor shall be estimated considering only retention and biofiltration BMPs located upstream of flow-thru BMPs. That is, if the flow-thru BMP is upstream of the project's retention and biofiltration BMPs then the flow-thru BMP shall be sized using an adjustment factor of 1. 2,504 0 0 2,504 1 1.321 0.90 0.238 SITE SPECIFIC DATA PROJECT NUMBER 8709 ORDER NUMBER ---- PROJECT NAME BMW OF CARLSBAD PROJECT LOCATION CARLSBAD, CA STRUCTURE ID MWS UNIT TREATMENT REQUIRED VOLUME BASED {CF) FLOW BASED {CFS) N/A 0.239 TREATMENT HGL AVAILABLE {FT) N/A PEAK BYPASS REQUIRED {CFS) -IF APPLICABLE 7.62 PIPE DATA I.£ MATERIAL DIAMETER INLET PIPE 1 90.57 N/K N/K INLET PIPE 2 N/A N/A N/A OUTLET PIPE 87.57 N/K N/K PRETREATMENT BIOFILTRATION DISCHARGE RIM ELEVATION 93.15 93.15 93.15 SURFACE LOAD PEDESTRIAN N/A PEDESTRIAN FRAME & COVER ¢JO" OPEN PLANTER ¢24" WETLANDMEDIA VOLUME {CY) 5.57 ORIFICE SIZE {DIA. INCHES) ¢2.19" NOTES: PRELIMINARY NOT FOR CONSTRUCT/ON. EOW TO PROVIDE FOOTING DETAILS. INSTALLATION NOTES 1. CONTRACTOR TO PROVIDE ALL LABOR, EQUIPMENT, MATERIALS AND INCIDENTALS REQUIRED TO OFFLOAD AND INSTALL THE SYSTEM AND APPURTENANCES IN ACCORDANCE WITH THIS DRAWING AND THE MANUFACTURERS SPECIFICATIONS, UNLESS OTHERWISE STATED IN MANUFACTURERS CONTRACT. 2. UNIT MUST BE INSTALLED ON LEVEL BAS£ MANUFACTURER RECOMMENDS A MINIMUM 6" LEVEL ROCK BASE UNLESS SPECIFIED BY THE PROJECT ENGINEER. CONTRACTOR IS RESPONSIBLE TO VERIFY PROJECT ENGINEERS RECOMMENDED BASE SPECIFICATIONS. 4. CONTRACTOR TO SUPPLY AND INSTALL ALL EXTERNAL CONNECTING PIPES. ALL PIPES MUST BE FLUSH WITH INSIDE SURFACE OF CONCRETE {PIPES CANNOT INTRUDE BEYOND FLUSH}. INVERT OF OUTFLOW PIPE MUST BE FLUSH WITH DISCHARGE CHAMBER FLOOR. ALL PIPES SHALL BE SEALED WATER TIGHT PER MANUFACTURERS STANDARD CONNECTION DETAIL. 5. CONTRACTOR RESPONSIBLE FOR INSTALLATION OF ALL RISERS, MANHOLES, AND HATCHES. CONTRACTOR TO GROUT ALL MANHOLES AND HATCHES TO MATCH FINISHED SURFACE UNLESS SPECIFIED OTHERWISE 6. VEGETATION SUPPLIED AND INSTALLED BY OTHERS. ALL UNITS WITH VEGETATION MUST HAVE DRIP OR SPRAY IRRIGATION SUPPLIED AND INSTALLED BY OTHERS. 7. CONTRACTOR RESPONSIBLE FOR CONTACTING BIO CLEAN FOR ACTIVATION OF UNIT. MANUFACTURERS WARRANTY IS VOID WITH OUT PROPER ACTIVATION BY A BIO CLEAN REPRESENTATIVE GENERAL NOTES VERTICAL UNDERDRAIN MANIFOLD 93.15 RIM/FG FLOW CONTROL RISER C/L DRAIN DOWN LINE PLAN VIEW C/L ELEVATION VIEW INTERNAL BYPASS DISCLOSURE: WETL.ANDMEDIA BED PATENTED PERIMETER VOID AREA THE DESIGN AND CAPACITY OF THE PEAK CONVEYANCE METHOD TO BE REVIEWED AND APPROVED BY THE ENGINEER OF RECORD. HGL{S) AT PEAK FLOW SHALL BE ASSESSED TO ENSURE NO UPSTREAM FLOODING. PEAK HGL AND BYPASS CAPACITY SHOWN ON DRAWING ARE USED FOR GUIDANCE ONLY. LEFT END VIEW ~~ 11~ .... ~-+-i.::;~=:.::d~~J.11 • co 5•Y .-----r =g:-----.r-6· RIGHT END VIEW TREATMENT FLOW {CFS) 0.239 OPERA TING HEAD {FT) 3.5 PRETREATMENT LOADING RATE (GPM/SF) 2.1 WETLAND MEDIA LOADING RATE {GPM/SF} 1.0 1. MANUFACTURER TO PROVIDE ALL MATERIALS UNLESS OTHERWISE NOTED. 2. ALL DIMENSIONS, ELEVATIONS, SPECIFICATIONS AND CAPACITIES ARE SUBJECT TO CHANG£ FOR PROJECT SPECIFIC DRAWINGS DETAILING EXACT DIMENSIONS, WEIGHTS AND ACCESSORIES PLEASE CONTACT BIO CLEAN. ~ , .. , PROPRIETARY AND CONFIDENTIAL: A_ ~ETLANDS THE INFDRMA710N CONTAINED IN THIS DOCUMENT IS THE SOI.£ 8 ·1 o .DA\._.v Cl ea n PROPERTY OF FORTERRA ANO llS COUPANIES. THIS DOCUMENT, '1/: :::::ltJ; =-~~ ~4~ IT NOR ANY PAl?T THEREOF, MAY BE USED, REPRODUCED OR MOOIAED MWS-L-8-8-5'-6"-V-HC STORMWATER 8/0FIL TRATION SYSTEM STANDARD DETAIL ~~Jis~RfZA1E11 FDIIEICN PATENTS OR IN ANY MANNER WITH OI/T THE WRITTEN CONSENT OF FOHTERRA. A foriaTa Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 23 of 27 ATTACHMENT 2 BACKUP FOR PDP HYDROMODIFICATION CONTROL MEASURES [This is the cover sheet for Attachment 2.] Indicate which Items are Included behind this cover sheet: Attachment Sequence Contents Checklist Attachment 2a Hydromodification Management Exhibit (Required) ☑ Included See Hydromodification Management Exhibit Checklist on the back of this Attachment cover sheet. Attachment 2b Management of Critical Coarse Sediment Yield Areas (WMAA Exhibit is required, additional analyses are optional) See Section 6.2 of the BMP Design Manual. ☑ Exhibit showing project drainage boundaries marked on WMAA Critical Coarse Sediment Yield Area Map (Required) Optional analyses for Critical Coarse Sediment Yield Area Determination: ☐ 6.2.1 Verification of Geomorphic Landscape Units Onsite ☐ 6.2.2 Downstream Systems Sensitivity to Coarse Sediment ☐ 6.2.3 Optional Additional Analysis of Potential Critical Coarse Sediment Yield Areas Onsite Attachment 2c Geomorphic Assessment of Receiving Channels (Optional) See Section 6.3.4 of the BMP Design Manual. ☑ Not performed ☐ Included Attachment 2d Flow Control Facility Design and Structural BMP Drawdown Calculations (Required) See Chapter 6 and Appendix G of the BMP Design Manual ☑ Included ☐ Submitted as a separate stand- alone document c:~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 24 of 27 Use this checklist to ensure the required information has been included on the Hydromodification Management Exhibit: The Hydromodification Management Exhibit must identify: ☑ Underlying hydrologic soil group ☑ Approximate depth to groundwater ☑ Existing natural hydrologic features ( watercourses, seeps, springs, wetlands) ☑ Critical coarse sediment yield areas to be protected (if present) ☑ Existing topography ☑ Existing and proposed site drainage network and connections to drainage offsite ☑ Proposed grading ☑ Proposed impervious features ☑ Proposed design features and surface treatments used to minimize imperviousness ☑ Point(s) of Compliance (POC) for Hydromodification Management ☑ Existing and proposed drainage boundary and drainage area to each POC (when necessary, create separate exhibits for pre-development and post-project conditions) ☑ Structural BMPs for hydromodification management (identify location, type of BMP, and size/detail) c:~Commercial Development Resources ATTACHMENT 2A: HYDROMODIFICATION MANAGEMENT EXHIBIT . \ ___;,. / / WV STOP ' I I ENTI RE SITE ULTIMATELY DISCHARGES TO CITY'S SD SYSTEM . • I ROOFDOWN I --DRAIN TO BMP-5 r OMA-1C 0.520AC \ _\ • • • • I ~\ l STRUCTURAL BMP-6B UNDERGROUND DETENTION SYSTEM FOR HYDROMODIFICATION MANAGEM ENT . l 1 =l!ell t (HYDRAULICALLY CONNECTED TO BMP-6A) ~ ~ ~~~--~~( 1- -~"' r -. •· . .. l f "'- OMA-1E 1.321 AC - I I I I I I STRUCTURAL BMP-6A: I yc:2::-;¾:2,;,;~ UNDERGROUND DETENTION SYSTE M FOR 1-1 ~~===::J'::';:'.;~~~~~~"~ I ~ HYDROMODI FICATION MANAGEMENT F I 0 '"""' /,c:i---~ I I I I I .,.,.,., ·/Uf,7""f'=#oa'4, l __ L __ I : I ",,,~,. \ I iiri'':'---.-~ __ _j I ' I Ii If I (HYDRAULICALLY CONNECTED TO BMP-6B) I . -k t ipJ I C) ROOF STORM DRAIN I I 1i ' 1---- 1 SYSTEM PER MEP PLANS _,, __ ) ' ( I/IH ---,.-1 I /llt----:1::-+-"'~, 0 'it't--+:~I I Wt--+-1 II it ]rt-..,i,..;1-~ I I ~ ' CAR RAMP FLOWS TO DMA-1C \1 r:.:.:., =lli!---- lt,1 ::: n . t . ,I d I I 0 DOWN TO BMP-5 I 0 ~~f ll~J~1i~~~~~ _ ROOF STORM DRAIN SYSTEM PER MEP PLANS OMA-10 0.404AC I I ' I ll I '\ L PROPOSED BUILDING W/ ROOFTOP PARKING I \ I T I I • @· I ~~~~~SEE • J I -t 1")3t . I - t I • ., . ' • J • ·1 • I • • I I I , ' L -- \ . " .. ~ll~a......----1-.b-~ ...... lpllllll!!I!!!'~. -~--~~-.·--··:>_ .. ,"""'~:/- STRUCTURAL BMP-4 <I! T-? ~ /1, .,-. '" - I I I "'" I ii\ I BIOFILTRATION (BF-1) FOR POLLUTANT ~•'-~t : ,· CONTROL AND HYDROMODIFICATION \, ' MANAGEMENT \ ' -----7a --~--' ..........,. ------------------ .. .. . . .. . . .. . . . . . .. __ . .. ............ ...._. STRUCTURAL BMP-2 BIOFILTRATION W/ PARTIAL RETENTION (PR -1) FOR POLLUTANT CONTROL AND HYDROMODIFICATION MANAGEMENT ------I ·~-----~-----s.c· "~ R AUTO CENTE~ CT .j:...~ I '- I I I I I I I I I I I I ,._ • • I I I I I I I I I I I I I I I I / I I I I I I I I I I I I I I I / I LEGEND: ~I -~I ASPHALT (IMPERVIOUS) I ·' • I CONCRETE (IMPERVIOUS) l LANDSCAPE ~-- PROPOSED ROOF AREA OMA BOUNDARY PROP ERTY LINE CENTERLINE SURFACE FLOW DI RECTION PROPOSED SD SYSTEM (□MA-#) OMA ID --cJ[)-PROPOSED CONTOUR EXISTING CONTOUR UNDERGROUND DETENTION VAULT I._.: . ' I BIOFILTRATION BASIN W/ PARTIAL RETENTION BIOFILTRATION BASIN W/ IMPERMEABLE LINER 1: : : : : : : :I PERM EABLE PAVERS 1m111m111mm MODULAR WETLAND SYSTEM (MWS) GEOTECHNICAL INFO: • HYDROLOGIC SOIL GROUP: B •INFILTRATION: 0.041 IN/HR • SOIL EXPANS IVE POTENTIAL VERY LOW • DEPTH TO GROUNDWATER: >50' CCSYA ANALYSIS: NO CR ITICAL COURSE SEDI MENT YIELD AREAS TO BE PROTECTED BASED ON WMAA MAPS BMP DETAILS: SEE SHEET 2 OF THIS EXH IBIT. 20 0 20 GRAPHIC SCALE SCALE: 1" = 20' 40 SHEET 01 OF 02 Q_ :, a " en "' u u a ~ w L a u ,i 2 rn, C 0 -a z 0 --------------------------------r---------------------;i, PREPARED FOR: AU TONATION INC. 200 SW 1ST STREET, 14TH FLOOR FORT LAUDERDALE, FL 33301 CONTACT CLIFF POWELL TEL (954) 769-6000 PREPARED BY: Today's Ideas Tomorrow's Reality Commercial Development Resources 4121 Westerly Place #11 2 Nev•p□rt 82ar.h CA 92660 SWQMP ATTACHMENT 2A: HMPEXHIBIT BMW OF CARLSBAD + u O' "' Q_ en I m CD 0 CD CD 0 " T 949 -610-8997 www.CDRwest.com _j "--••L. ,------v-/ / / ~-,A ~ L ____________________________________ :-===-==:::--:;;;;;;;;;;;;;;-;;;;-,;,;· ==·-----------------------------':_ _____ .. 1;_ __________________ .. ~,!l:i:;;i;)l"-½:.... ___ .... ____ _,L _______________________________ ..., _____________________ _ 1060 AUTO CENTER COURT CARLSBAD, CA 92008 _j 2 U) _J ~ w 0 ~ w 1---U) >-U) z 0 1-z w 1-w 0 U) _J ~ w 0 z U) <C co RISER INFORMATION STUB INFORMATION BM P-6A: PIECE RIM ELEV. SYSTEM PIECE STUB INVERT SYSTEM INVERT INVERT WEST OF PR OPOSED BUILDING 4'-0" 36"0 RISER A3 '" f ~ A 96"0BULKHEAO A1 W/ 12"0 STUB A2a THE UNDERSIGNED HEREBY APPROVES THE ATTACHED (4) PAGES INCLUDING THE FOLLOWING: • PIPE STORAGE = 5,681 CF • MAINLINE PIPE GAGE= 16 • WALL TYPE = SOLID • DIAMETER = 96" • FINISH= ALT2 • CORRUGATION= 5x1 CUSTOMER DATE Tte 1os~c. oc,J h,'crc-ctba slocw" en lh, de"''•'"" Is pm,;cl,d ", ser,;co lO ,no C<<;oct ,,.,,,,., '"""'" ..-d x.,1,acror"' G,.--,, Eo~"'"""" S,,·,.,~,,, U.G i'ICootech''.,. N,;,n,, lh" O,awlcs, ao· aa, "'"·"""''JI . .,,,,."' u,,c, ""'"'"""'" oc m:,;rt.eo ,n ,,., mon•ecw101o·Jtu-.e oror , .• ,"~' ,~os ot Ce'lt«.,. Fcll,r<iOCO~otl" ,,.., """ """ ,wo,51< '"' c,_h ""°'"'~' ,aoam, ,,, , ,hJ~· o, ,.,,r,on,lhify foe '"'''"'" 11 ,~erc,,ando, "''""'" '" '""''"" '"°'"""'" cooo ~, o-;i-o o,.,,,,,, 1, °"'"° ,n; ,du~ fi""1 oooca:oas ""' '"''""'"''' "''" ''•""' °'°'""""· '""'• ,1,0-,,,,ncia, most c, ""°""' co u,,_ 1m""'"'"~ ro, re·e\"elJ;)'"" or"" ""~"· c"'"'"' aoceots n, llabllt)• focc;,s·aos ""'' en mlss:ao, ~romp.,,. cr ;,-,"'"''";''"""'"""'''''"'''"''""'' MAR~ DATE REVISION DESCRIPTION BY HOT-DIP GALVAN IZED PLATE GREATER THAN UNDERDRAIN WI DRILLED HOLE ½" DIA. OPENING 4" INVERT OF 6" DIA. SLOTTED PVC UNDERDRAIN -BOTTOM OF BASI N FLOW CONTROL ORIFICE PLATE C I BAND, TYPICAL SEE DETAIL SHEET P3 C(~NTECH" ENGINEERED SOLUTIONS LLC www.ContechES.com 11815 NE Glenn Widing Drive. Portland, OR 97220 800-548-4667 503-240-3393 SU0-561-1 271 FAX 6" DIA. SLOTTED PVC UNDERDRAIN RISER WALL FLOW CONTROL ORIFICE PLATE, SEE DETAIL ABOVE BOTTOM OF BASIN \ NATURAL SOIL LID ORIFICE DETAIL AM ENDED 6" DIA SLOTTED = i ¼" DIA ORIFICE { 4" SOIL MEDIA PVC UNDERDRAIN «Y/_,,(<, '/,t(",'./(' -~'0'v«, ! >0 »;;;;»0_;~-d'$,:2$;»;$'f; f 3' SAND FILTER COURSE ____ 0 _____ 0 -~--- 0 __ --~ __ f,', PEA GRAVEL GRAVEL STORAGE O O o O o O o O 6 0 0 0 0 BOTTOM OF BASIN NATURAL SOIL 36"0 RISER A3 TBD 87.00 12"0 STUB A2 94.00 87.00 12"0 STUB B2 87.00 87,00 10"0 STUB 83 94.17 87.00 113'-0" I I I I I I I C C I B I I I I 96"0 BULKHEAD B1 I : W/ 12"0 STUB 82 f 4'-0" 10"0 STUB 83 NOTES • BULKHEADS SHALL BE 12-GAGE OR HEAVIER STEEL AND THE COATING WILL MATCH THE SPECIFIED CMP COATING. BULKHEAD PLATES SHALL BE FULLY WELDED ONTO THE CMP WITH STEEL REINFORCEMENT AS REQUIRED. THE STEEL REINFORCEMENT SHALL BE POST COATED WITH ZINC RICH PAINT PER AASHTO M 36. BULKHEAD DESIGNS SHALL SATISFY THE REQUIREMENTS SHOWN IN CHAPTER 8 OF THE NCSPA CSP DESIGN MANUAL AND CALCULATIONS SHALL BE PROVIDED TO THE ENGINEER OF RECORD (EOR) FOR APPROVAL UPON REQUEST ASSEMBLY • ALL FITTINGS SHALL BE STRUCTURALLY CHECKED FOR REINFORCEMENTS PER ASTM A998 AND PROVIDED TO THE EOR FOR APPROVAL UPON REQUEST SCALE: 1" = 10' • CONNECTING BANDS FOR DETENTION SYSTEMS SHALL BE HUGGER TYPE OR FULLY PIPE STORAGE : 5,681 CF CORRUGATED WITH APPROPRIATE BOLTED CONNECTIONS THAT CAN BE TORQUED TO 35 FOOT LOADING: H20 POUNDS. BANDS SHALL MATCH THE SPECIFIED CMP COATING AND MEET THE REQUIREMENTS PIPE INV.= 87.00'± OF AASHTO M 36. • All METALLIC COATINGS AFFECTED BY MANUFACTURING FABRICATION SHALL BE REPAIRED PER AASHTO M 36 SECTION 11 REQUIREMENTS (E.G. ZINC-RICH PAINT ON ALL WELDS) IF POLYMER COATINGS ARE USED THE REPAIR OF DAMAGED COATINGS WILL BE IN CONFORMANCE WITH AASHTO M 245 SECTION 11 REQUIREMENTS. • ACCESS LADDERS SHALL BE ATTACHED BY THE MANUFACTURER PRIOR TO DELIVERY, NOT INSTALLED ON THE JOBSITE. _,,11,:.auTr-u· 96"0 UNDERGROUND DETENTION SYSTEM -617515-010 ~~~ i I.V!"!! PROJECT No.: ISEQ. No.: I D/\TE 617515 010 5118/2021 CMP DETENTION SYSTEMS BMW CARLSBAD CARLSBAD , CA I CONTECH I PROPOSAL SITE DESIGNATION: BMP 6A DRAWING HOT-DIP GALVANIZED PLATE GREATER THAN UNDERDRAIN W/ DRILLED HOLE ¾" DIA OPENING 3" INVERT OF 6" DIA. SLOTTED PVC UNDERDRAIN ~ BOTTOM OF BASIN FLOW CONTROL ORIFICE PLATE LI D ORIFICE DETAIL AM ENDED 6" DIA SLOTTED SOIL MEDIA~' PVC UNDERDRAIN ij>-«-. '/A"«· -,;e/./''"« >"">-°'»'»70;.,_-:::f:,0;; --!-_-:::f;,"'»"-"'»;$'f; ! FILTER COURSE!' · ' ·. ·.>--·a'\ ' 3"SAND 3" PEA GRAVEL o O O O 0 GRAVEL STORAGE ) 0 0 ° 0 0 ° o O O o O ( 6' "/ ,,<'(\ IMPERMEABLE LINER AT BOTTOM OF BASIN \ NATURAL TO BE 30 MIL GSE HD SMOOTH LINER BY GSE SOIL ENVIRONM ENTAL OR APPROVED EQUIVALENT PLACEMENT OF SLOTTED UNDERDRAIN BMP-3 /]iliiiR I I · I t1 J I l , I I.- _l I l. - I ll J I DESIGNED RLH CHECKED SHEET NO P1 BMP-4 RISER DRAWN RLH APPROVED Ce 4 HORIZONTAL 6" DIA. SLOTTED PVC UNDERDRAIN C.O. BMP-4 BMP-6B: NORTH OF PROPOSED 4'-0" 36"0 RISER A4 96"0BULKHEADA1 / WI 12"0 STUB A2 WI 10"0 STUB A3 THE UNDERSIGNED HEREBY APPROVES THE ATTACHED {4) PAGES INCLUDING THE FOLLOWING: • PIPE STORAGE= 4,776 CF • MAINLINE PIPE GAGE= 16 • WALL TYPE = SOLID • DIAMETER = 96" • FINISH= ALT2 • CORRUGATION = 5x1 CUSTOMER DATE Tho do,,1., ac.1 ,Fonnocloo ,oo,,~ "' 1"1< <lmwlcs ls p<.,·,~c.<I "" '"''"' '" "'" µ,u);Cl """"· ,,,,;,~" """ co,,O<>Olc, ,, '.¼,ta,J, E,-~;,,,..o,,1 Sc.l,~o·" lLr-fG""1""1'>. N~he, 11-is dca,,aa. noc ,..,. ca1 Che,acl, m,, be"""· a,pwdococ oc n·o,,ni,,;, In Cll\' rno,n" ½11"°"' 1t>e OrlOC wrtt<n "'"""' o' Conte<h •• 0,·1-,01<> "'"""'' ;, oono at Lt>o ·.socs o,-·n M,K an, Gootech "'"""'' o;,,,,1,;,,, ")' llsblllc' n· .,.,s,,,nabllll; fee ''""""' tr "'"''""""' M'.wecn 1"' sc,o:IO<l lnloc..,,on u,:,:,n "~'" to. ,,.,.,;no 1, ,.,., aco ,ctu,1 ••Id c,,::dt&, ,., .,,,ecol,,.., ,a '"' ~o-, '"''"'"""· u-,e,e ""'""""' ,, mu,< bO ""'""' to un1ecn lmmMIO:~vt<r ro,ovOlcaron 01 ,no"'""· c:on1ecn """'" oo lla,1111,,.,,-des<>'s Cased ,a m~i,g, 1,00m,le1e ,c ;""""""'' """""":'"""'"'·";"'; """" MARf DATE REVISION DESCRIPTION BMP-1 RISER _____ -__________ ,:_ __ 7 ·' ...... ·.,· . ·. . . ' ., NOTE UNDERDRAIN ENTERS RISER AT ONLY 1 (ONE) SIDE BMP-2 RISER BMP-2 HORIZONTAL 6" DIA SLOTTED PVC UNDERDRAIN co l : I I I I I I .I I : I t l I BMP-1 PLAC EMENT OF SLOTTED UNDERDRAIN BASIN BMP RISER & SLOTTED UNDERDRAIN C.O. LAYOUT RETAINING WALL 3.33' VARIES PER PLAN 3'x3' RISER -(2'x2' INTERNALLY) OUTLET PIPE PER PLAN NOTE: SLOTTED UNDERDRAIN AND ORIFICE OUTLET NOT SHOWN TYPICAL BASIN CROSS-SECTI ON RETAINING WALL 6" FREEBOARD 6" PONDING 3" MULCH 18" AMENDED SOIL 3" SAND (FILTER) 3" PEA GRAVEL (FILTER) 7" GRAV EL (STORAG E) BMP-1 & BMP-2: BIOFILTRATION BASIN W/ PARTIAL RETENTION VARIES PER PLAN RETAINING WALL RETAINING WALL 3.25' NOTE 3'x3' RISER -(2'x2' INTER NALLY) ·~-'v Yi ,✓,. (%JTl'.'.ET " PIPE IMPERMEABLE LINER. SEE NOTES 1. SLOTTED UNDERDRAIN AND OR IFICE OUTLET NOT SHOWN 2. IMPERMEABLE LINER TO BE 30 MIL GSE HD SMOOTH LINER FROM GSE ENVIRONM ENTAL OR APPROVED EQU IVALENT TYPICAL BAS IN CROSS-SECTION 6" FREEBOARD 6" PONDING 3" MULCH 18" AMENDED SOIL 3" SAND (FILTER) 3" PEA GRAVEL (FILTER) 6" GRAVEL (STORAG E) BMP-3 & BMP-4: BIOFIL TRATION BASIN W/ IMPERMEABLE LINER cl C n I 6" DIA. SLOTTED PVC UNDERDRAIN \ ~" 9 .. p ' 0 0 o . 0 i, 0 O G if ORIFICE Vi PLATE n -- OUTFALL PIPE SIZE & , • LOCATION PER PLAN ,,,,---- BASIN BMP RISER OUTLET DETAIL 0 , 6" PVC SCREW CAP / WATERTIGHT CAP ON TERMINAL END OF PIPE 6" DIA SLOTTED PVC UNDERDRAIN CONN ECTED TO DOWNSTREAM CLEANOUT OR SQUARE RISER UNDERDRAIN CLEANOUT (C .O.) DETAIL STUB INFORMATION PIECE STUB INVERT SYSTEM INVERT BUILDING 12"0 STUB A2 87.00 87.00 10"0 STUB A3 94.17 87.00 12"0 STUB B2 94.00 87_00 RISER INFORMATION PIECE RIM ELEV SYSTEM INVERT 95'-0" 36"0 RISER A4 TBD 87.00 ,, I I I I I I I I I ~ 96"0 BULKHEAD 8 1 A I C I C I B I I I I I I I I I ,, WI 12"0 STUB B2 BAND, TYPICAL SEE DETAIL SHEET P3 NOTES • BULKHEADS SHALL BE 12-GAGE OR HEAVIER STEEL AND THE COATING WILL MATCH THE SPECIFIED CMP COATING. BULKHEAD PLATES SHALL BE FULLY WELDED ONTO THE CMP WITH STEEL REINFORCEMENT AS REQUIRED. THE STEEL REINFORCEMENT SHALL BE POST COATED WITH ZINC RICH PAINT PER AASHTO M 36. BULKHEAD DESIGNS SHALL SATISFY THE REQUIREMENTS SHOWN IN CHAPTER 8 OF THE NCSPA CSP DESIGN MANUAL AND CALCULATIONS SHALL BE PROVIDED TO THE ENGINEER OF RECORD (EOR) FOR APPROVAL UPON REQUEST ASSEMBLY • ALL FITTINGS SHALL BE STRUCTURALLY CHECKED FOR REINFORCEMENTS PER ASTM A998 AND PROVIDED TO THE EOR FOR APPROVAL UPON REQUEST SCALE: 1" = 10' • CONNECTING BANDS FOR DETENTION SYSTEMS SHALL BE HUGGER TYPE OR FULLY PIPE STORAGE: 4,776 CF CORRUGATED WITH APPROPRIATE BOLTED CONNECTIONS THAT CAN BE TORQUED TO 35 FOOT LOADI NG: H20 POUNDS. BANDS SHALL MATCH THE SPECIFIED CMP COATING AND MEET THE REQUIREMENTS PIPE INV.= 87.00'± OF AASHTO M 36. • ALL METALLIC COATIN GS AFFECTED BY MANUFACTURING FABRICATION SHALL BE REPAIRED PER AASHTO M 36 SECTION 11 REQUIREMENTS {E.G. ZINC-RICH PAINT ON ALL WELDS). IF POLYMER COATINGS ARE USED THE REPAIR OF DAMAGED COATINGS WILL BE IN CONFORMANCE WITH AASHTO M 245 SECTION 11 REQUIREMENTS. • ACCESS LADDERS SHALL BE ATTACHED BY THE MANUFACTURER PRIOR TO DELIVERY, NOT INSTALLED ON THE JOBSfTE. PROJECT No.: ISEQ. No., I DATE C()NTECH" A s,111,:.a .. rrr-u· 96"0 UNDERGROUND DETENTION SYSTEM -617515-020 617515 020 5118/2021 V~~;,w i I.V!"!! DESIGNED DRAWN ENGINEERED SOLUTIONS LLC CMP DETENTION SYSTEMS BMW CARLSBAD RLH RLH www.ContechES.com CARLSBAD, CA CHECKED APPROVED 11815 NE Glenn Widing Dri.,e. Portland. OR 97220 I PRO~TOC'SAL I SITE DESIGNATION: BMP 6B BY 800-548-4667 HORIZONTAL 6" DIA. SLOTTED PVC UNDERDRAIN co 503-240-3393 800-561-1271 FAX DRAWING NOTES: 1. BMP-6A A ND BMP-6B TO ACT AS ONE DETENTION SYSTEM THAT IS HYDRAULICALY CONNECTED VIA 12" HOPE PIPE A ND SET AT O NE ELEVATION. 5.66' 5.0' SHEET NO P1 Ce 4 I 95 OOTW 2 . BMP-6 SHALL HAVE A MINIMUM TOTA L STORAGE VOLUME OF 10,440 CU-FT. I -1~·'"'1=N~TE=R~N~A~L_T_O_P_ --;-~·1 ______ ==,,,.---~'"i--1~ OF STRUCTURE 94.21 FL METAL PLATE GREATER THAN 6" DIA OPENING 6" PVC PIPE EMBEDDED IN 4" CONCRETE WALL 1.125" DIA. OR IFICE THRU PLATE FLOW CONTROL ORIFICE PLATE 4.0' 0.79' 7.21 ' A t <I. Li <J <J Li L'.l Li 6" PVC PIPE EMBEDDED IN CONCRETE ------~-+---~---------t-~ 0.5' 4.0' 15" DIA. H PE OUTLET PIPE TO PUBLIC SD LINE 0.5' CONCRETE WEIR WALL OR IFICE PLATE t 12" DIA. HOPE INLET PIPE FROM ONSITE DETENTION VAULT (BMP-6B) 12" DIA HOPE INLET PIPE FROM ONS ITE DETENT ION VAULT (BMP-6A) OUTLET STRUCTURE & WEIR DETAIL OVERFLOW WEIR Li <J <J Li ,1 <J <I METAL PLATE ON OUTLET SIDE OF WEIR. SEE DETAIL AB~VE I 87.00INV ~lccNcccTEacRc'cN.ccA-L~B~O=TT=o ~M <J OF STRUCTURE " ,1 ,1 1.125" DIA. OR IFICE · THR U METAL PLATE SHEET 02 OF 02 A t Q_ :, a " en <{ u u a ~ w L a u ,i 2 ml C 0 -a z 0 t,------------------------------------------------------------------1-i' PREPARED FOR: PREPARED BY: AU TONATION INC. 200 SW 1ST STREET, 14TH FLOOR FORT LAUDERDALE, FL 33301 CONTACT CLIFF POWELL TEL (954) 769-6000 Today's Ideas Tomorrow's Reality Commercial Development Resources 4121 Westerly Place #11 2 NevLiport Beach CA 92660 T 949-610-8997 www.CDRwest.com SWQMP ATTACHMENT 2A: HMPEXHIBIT BMW OF CARLSBAD 1060 AUTO CENTER COURT CARLSBAD, CA 92008 I + u O' <{ Q_ en I m CD 0 CD CD 0 " I .._ ____________________________________________________________________________________________________________________ .., _________________________________ .., ______________________ _ ATTACHMENT 2B: WMAA EXHIBIT 0 u ;! Q) C gj 13 8 (l.) 0 ATTACHMENT 2C: NOT INCLUDED ATTACHMENT 2D: TECHNICAL MEMORANDUM: SWMM Modeling for Hydromodification Compliance of: BMW Carlsbad Prepared For: CDR Prepared by: Luis Parra, PhD, CPSWQ, ToR, D.WRE. R.C.E. 66377 REC Consultants 2442 Second Avenue San Diego, CA 92101 Telephone: (619) 232-9200 TECHNICAL MEMORANDUM TO: CDR. FROM: Luis Parra, PhD, PE, CPSWQ, ToR, D.WRE, CFM. David Edwards, MS, PE, CFM. DATE: December 13, 2019 RE: Summary of SWMM Modeling for Hydromodification Compliance for BMW Carlsbad, City of Carlsbad, CA. INTRODUCTION This memorandum summarizes the approach used to model the proposed commercial site in the City of Carlsbad using the Environmental Protection Agency (EPA) Storm Water Management Model 5.0 (SWMM). SWMM models were prepared for the pre and post‐developed conditions at the site in order to determine if the proposed LID HMP bio‐filtration and underground detention facilities have sufficient volume to meet Order R9‐2013‐001 requirements of the California Regional Water Quality Control Board San Diego Region (SDRWQCB), as explained in the Final Hydromodification Management Plan (HMP), dated March 2011, prepared for the County of San Diego by Brown and Caldwell. SWMM MODEL DEVELOPMENT The BMW Carlsbad project proposes a commercial structure and servicing parking lots on the currently developed site. Two (2) SWMM models were prepared for this study: the first for the predevelopment and the second for the post‐developed conditions. The project site drains to one (1) Point of Compliance (POC‐1) located at the existing storm drain system located to the north of the project site. Per Section G1.2 in Appendix G of the 2016 City of Carlsbad BMP Design Manual, the EPA SWMM model was used to perform the continuous hydrologic simulation. For both SWMM models, flow duration curves were prepared to determine if the proposed HMP facilities are sufficient to meet the current HMP requirements. The inputs required to develop SWMM models include rainfall, watershed characteristics, and BMP configurations. The Oceanside Gage from the Project Clean Water website was used for this study since it is the most representative of the project site precipitation due to elevation and proximity to the project site. Per the California Irrigation Management Information System “Reference Evaporation Zones” (CIMIS ETo Zone Map), the project site is located within the Zone 1 Evapotranspiration Area. Thus evapotranspiration vales for the site were modeled using Zone 1 average monthly values from Table G.1‐1 from the 2016 BMP Design Manual. Per the site specific geotechnical investigation and NRCS Web Soil Survey, the project site is situated upon Class B soils. Soils have been assumed to be compacted in the existing developed condition while fully compacted in the post developed conditions. Other SWMM inputs for the subareas are discussed in the appendices to this document, where the selection of parameters is explained in detail. R·E·C BMW Carlsbad HMP Memo December 13, 2019 2 W.O.7063‐02 HMP MODELING PRE DEVELOPED CONDITIONS The current site consists of a developed lot that drains via overland flow to the receiving storm drain system located to the north of the project site within the adjacent Cannon Road. Table 1 below illustrates the pre‐developed area to be redeveloped and impervious percentage accordingly. TABLE 1 – SUMMARY OF PRE‐DEVELOPED CONDITIONS POC DMA Tributary Area, A (Ac) Impervious Percentage, Ip(1) POC‐1 DMA‐A 3.71 0% TOTAL ‐‐ 3.71 0% Notes: (1) – Per the 2013 RWQCB permit, existing condition impervious surfaces are not to be accounted for in existing conditions analysis. DEVELOPED CONDITIONS Storm water runoff from the proposed project site is routed to one (1) POC located at the existing storm drain location to the north of the project site. Runoff from the developed project site is drained to five (5) onsite receiving BMPS; four (4) biofiltration LID BMP’s and a two (2) underground detention vaults that are hydraulically linked to act as a single detention facility. Once flows are routed via the proposed LID BMPs, developed onsite flows are then conveyed to the POC. A small portion of the site is self‐ mitigating; this area will bypass the LID BMPs and confluence with flows at the aforementioned POC. TABLE 2 – SUMMARY OF POST‐DEVELOPED CONDITIONS POC DMA Tributary Area, A (Ac) Impervious Percentage, Ip POC‐1 DMA‐1A + Pavers 0.726 61.23 BR‐1 0.01843 0% DMA‐1B 0.325 61.22% DMA‐1B (Pavers) 0.089 0% BR‐2 0.00817 0% DMA‐1D 0.341 96.62% DMA‐1D (Pavers) 0.053 0% BR‐3 0.01279 0% DMA‐1C 0.506 92.52% BR‐4 0.01 0% DMA‐1E 1.325 100% DMA‐2A (Self Mitigating) 0.294 6.73% TOTAL ‐‐ 3.71 ‐‐ Four (4) LID biofiltration basins and a single underground detention vault are located within the project site and are responsible for handling hydromodification requirements. In developed conditions, the basins will have a surface depth of 0.92 feet and a riser spillway structure (see dimensions in Table 4). Flows will then discharge from the basins via a low flow orifice outlet within the gravel layer. The riser BMW Carlsbad HMP Memo December 13, 2019 3 W.O.7063‐02 structure will act as a spillway such that peak flows can be safely discharged to the receiving underground detention vault. Beneath the basins’ invert lies the proposed LID biofiltration portion of the drainage facility. This portion of the basin is comprised of a 3‐inch layer of mulch, an 18‐inch layer of amended soil (a highly sandy, organic rich composite with an infiltration capacity of at least 5 inches/hr). Two (2) of the BMP’s (BR‐1 and BR‐2) are partial‐retention systems; these basins will feature 13‐inches of gravel while the remaining two (2) bio‐filtration BMPs (BR‐3 and BR‐4) will be lined and include a 12‐inch layer of gravel for additional detention and to accommodate the French drain system. These systems are to be located beneath the biofiltration layers to intercept treated storm water and convey these flows to a single small diameter lower outlet orifice. Once the runoff has been routed by the outlet structure, flows are then drained to the receiving underground detention vaults for additional detention. The two (2) spate vaults are to be constructed at the same elevation and will be linked via the junction box that houses the single outlet structure for the two (2) facilities. Given that the basin elevations are the same and that both basins are constricted by the same outlet structure, these facilities are hydraulically linked and act as a single detention facility for modeling purposes. After these flows have been detained via the detention vault, they will be discharged to the existing storm drain system located within the adjacent Cannon Road. The biofiltration basins were modeled using the biofiltration LID module within SWMM. The biofiltration module can model the underground gravel storage layer, underdrain with an orifice plate, amended soil layer, and a surface storage pond up to the elevation of the invert of the spillway. It should be noted that detailed outlet structure location and elevations will be shown on the construction plans based on the recommendations of this study. Water Quality BMP Sizing It is assumed all storm water quality requirements for the project will be met by the bio‐filtration LID BMPs detailed in the SWQMP and other BMPs included within the site design. However, detailed water quality requirements are not discussed within this technical memo. For further information in regards to storm water quality requirements for the project (including sizing and drawdown) please refer to the site specific Storm Water Quality Management Plan (SWQMP). Porous Pavers As an integrated LID BMP design practice, several sections of the project sites parking lots will feature porous pavement/pavers. These porous sections will include a 6‐inch layer of gravel to be located beneath the paver to allow for storage of intercepted runoff. There will be no French drain located beneath the paver section such that once the volume of voids of the gravel has been filled with stormwater, any excess storm water will continue to surface flow to the receiving storm water quality bio‐filtration basin. The paver base will be unlined to allow for infiltration into the underlying soil. In some DMA’s, cross gutters prevent run‐on from adjacent impervious areas into these pervious sections, such that the only runoff tributary to these LIDs is the direct precipitation that falls upon them. The DMA’s located within the north‐eastern portion of the site however do not feature cross gutters, thus allowing for run‐on from the adjacent impervious areas. BMW Carlsbad HMP Memo December 13, 2019 4 W.O.7063‐02 To represent these differences within the SWMM model, the DMA’s that are run‐on to the pervious areas (DMA‐1A) are modeled as draining to pervious. Whereas for the porous pavement areas that do not receive run‐on, these areas are modeled as their own individual catchment within SWMM, allowing for the accurate representation of impervious runoff from adjacent DMA’s to bypass these porous pavement sections and drain directly to the BMP. Additionally, to represent the 6‐inches of gravel storage located beneath the porous pavement French Drain, the “Dstore‐Perv” value for the catchment representing the porous pavement is set to 4.8‐inches (as 12 inches of gravel has only 40% of voids space available for storage, thus 6 X 0.4 = 2.4). It should be noted that the pavers are not treatment control BMPs and as such no draw‐down calculations are required; the 57‐year continuous hydrologic SWMM model demonstrates the pavers are able to meet their HMP objective. The bio‐filtration BMPs downstream of the pavers have been sized for the full DCV and have not been reduced due to the volumetric interception provided by the paver. BMP MODELING FOR HMP PURPOSES Modeling of dual purpose Water Quality/HMP BMPs Four (4) HMP BMP biofiltration basins and two (2) underground detention vaults are proposed hydromodification conformance for the project site. Tables 4, 5 and 6 illustrate the dimensions required for HMP compliance according to the SWMM model that was undertaken for the project. TABLE 4 – SUMMARY OF DEVELOPED DUAL PURPOSE WQ & HMP BMPs BMP Tributary Area (Ac) DIMENSIONS BMP Area(1) (ft2) Gravel Depth(2) (in) Lower Orif. D (in)(3) Depth Riser Invert (ft)(4) Weir Perimeter Length(5) (ft) Total Surface Depth(6) (ft) BR‐1 0.726 803 13 0.875 0.75 8.0 0.92 BR‐2 0.414 356 13 0.675 0.75 8.0 0.92 BR‐3 0.394 557 12 0.75 0.75 8.0 0.92 BR‐4 0.506 435 12 0.75 0.75 8.0 0.92 Notes: (1): Area of amended soil equal to area of gravel (2): Includes filter gravel layer, French Drain is set at an elevation of 3‐inchesor 4‐inches above the base of the facility. (3): Diameter of orifice in gravel layer with invert at bottom of layer; tied with hydromod min threshold (0.1∙Q2). (4): Depth of ponding beneath riser structure’s surface spillway. (5): Overflow length, the internal perimeter of the riser is 8 ft (2ft x 2ft internal dimensions). (6): Total surface depth of BMP from top crest elevation to surface invert. TABLE 5– SUMMARY OF DETENTION VAULTS: Basin Area (ft2) Depth (ft) Volume (ft3) DETENTION VAULT 1,305 8 10,440 Notes: (1): Volume/area to be distributed between the two (2) individual detention facilities. BMW Carlsbad HMP Memo December 13, 2019 5 W.O.7063‐02 TABLE 6 – SUMMARY OF DETENTION VAULT RISER DETAILS: BASIN Lower Orifice Emergency Weir Diameter (in) Number of Orifices Elev.(1) (ft) Width (ft) Elev.(1) (ft) DETENTION VAULT 1.125 1 0.0 5 7.2083 Notes: (1): Invert of basin surface assumed to be elevation 0.0’. FLOW DURATION CURVE COMPARISON The Flow Duration Curve (FDC) for the site was compared at the POC by exporting the hourly runoff time series results from SWMM to a spreadsheet. Q2 and Q10 were determined with a partial duration statistical analysis of the runoff time series in an Excel spreadsheet using the Cunnane plotting position method (which is the preferred plotting methodology in the HMP Permit). As the SWMM Model includes a statistical analysis based on the Weibull Plotting Position Method, the Weibull Method was also used within the spreadsheet to ensure that the results were similar to those obtained by the SWMM Model. The range between 10% of Q2 and Q10 was divided into 100 equal time intervals; the number of hours that each flow rate was exceeded was counted from the hourly series. Additionally, the intermediate peaks with a return period “i” were obtained (Qi with i=3 to 9). For the purpose of the plot, the values were presented as percentage of time exceeded for each flow rate. FDC comparison at the POC is illustrated in Figure 1 in both normal and logarithmic scale. Attachment V provides a detailed drainage exhibit for the post‐developed condition. As can be seen in Figure 1, the FDC for the proposed condition with the HMP BMPs is within 110% of the curve for the existing condition in both peak flows and durations. The additional runoff volume generated from developing the site will be released to the existing point of discharge at a flow rate below the 10% Q2 lower threshold for POC‐1. Additionally, the project will also not increase peak flow rates between the Q2 and the Q10, as shown in the peak flow tables in Attachment I. Discussion of the Manning’s coefficient (Pervious Areas) for Pre and Post‐Development Conditions Typically the Manning’s coefficient is selected as n = 0.10 for pervious areas and n = 0.012 for impervious areas. Due to the complexity of the model carried out in pre and post‐development conditions, a more accurate value of the Manning’s coefficient for pervious areas has been chosen. Taken into consideration the “Handouts on Supplemental Guidance – Handout #2: Manning’s “n” Values for Overland Flow Using EPA SWMM V.5” by the County of San Diego (Reference [6]) a more accurate value of n = 0.05 has been selected (see Table 1 of Reference [6] included in Attachment VII). An average n value between pasture and shrubs and bushes (which is also the value of dense grass) has been selected per the reference cited, for light rain (<0.8 in/hr) as more than 99% of the rainfall has been measured with this intensity. BMW Carlsbad HMP Memo December 13, 2019 6 W.O.7063‐02 SUMMARY This study has demonstrated that the proposed HMP BMPs provided for the BMW Carlsbad project site is sufficient to meet the current HMP criteria if the cross‐section areas and volumes recommended within this technical memorandum, and the respective orifice and outlet structure are incorporated as specified within the proposed project site. KEY ASSUMPTIONS 1.Type B Soils is representative of the existing condition site. 2.Two (2) separate detention vaults will be constructed at the same elevation and hydraulically linked, acting as a single detention system. ATTACHMENTS I.Q2 to Q10 Comparison Tables II.FDC Plots (log and natural “x” scale) and Flow Duration Table. III.List of the “n” largest Peaks: Pre‐Development and Post‐Development Conditions IV.Elevations vs. Discharge Curves to be used in SWMM V.Pre & Post Development Maps, Project plan and section sketches VI.SWMM Input Data in Input Format (Existing and Proposed Models) VII.SWMM Screens and Explanation of Significant Variables VIII.Geotechnical Documentation IX.Summary files from the SWMM Model REFERENCES [1]– “Review and Analysis of San Diego County Hydromodification Management Plan (HMP): Assumptions, Criteria, Methods, & Modeling Tools – Prepared for the Cities of San Marcos, Oceanside & Vista”, May 2012, TRW Engineering. [2]– “Final Hydromodification Management Plan (HMP) prepared for the County of San Diego”, March 2011, Brown and Caldwell. [3]‐ Order R9‐20013‐001, California Regional Water Quality Control Board San Diego Region (SDRWQCB). [4]– “Handbook of Hydrology”, David R. Maidment, Editor in Chief. 1992, McGraw Hill. [5]– “City of Carlsbad BMP Design Manual”, February 2016. [6]– “Improving Accuracy in Continuous Hydrologic Modeling: Guidance for Selecting Pervious Overland Flow Manning’s n Values in the San Diego Region”, 2016, TRW Engineering. BMW Carlsbad HMP Memo December 13, 2019 7 W.O.7063‐02 Figure 1a and 1b. Flow Duration Curve Comparison (logarithmic and normal “x” scale) BMW Carlsbad POC 1-Flow Duration Curve ).)S 1.75 Qi"·-____ l _________ ·-·-·-·-·-·-·-·-·l ·-·-·-·-· ·----~ --Exi~tinf; :'g_ 1.2!; +---+--------'>c-+-------+---------+-------+--1 --Pmpof.<'!rt Cl -. -Ux o.75 .stt;· _. _. ·-·-·-·-·-·-·-·-·-·-·-·-·-·-·-·-·-o:sQ, - --- -·- ---·-------·- --o:3Q, U.l~ ~:-=~=--:-=-1~=-:-=~=--:-=-!~:-:-=~~~~~~~~;::t ~::==~jt~~=-:::1 ~.I(ti·-·-·-· ·-·-·-·-·-·-·-·-·-1·-·-·-·-· , . ·-·-·-·-·~1Qi i Cl 0 +------~--------.--------------+-----------------1 0 0.02 0.04 O.OG PP.rr.P.nt11eP. nf timP. P.U-.P.P.riP.d (%) BMW Carlsbad POC 1-Flow Duration Curve 1.b ,----,----------,--------------------,---,--,-,-----,----- JJ 1.8 1.6 1.1 l.l 0.8 0.6 0.'1 O.l 0 u ·-·-·-·-·-·-·-·-·-·-·-·-·-·-·-·-•-4-•-·-·-·-·-·-·-·-·-·-·-·-·-·-·-·-·-·-·-·-·--·-·-·-·-·-·-·-·-·-·-·-·-·-·-·-•-4-•-·-·-·-·-·-·-·-·-·-·-·-·-·-·-·-·-·-·-·-·- Qi ---- -----·--------- -----------------------------·------'------------------~- na· ·-· ·- - -·- -·-·- -·-·- - -·- -,-·-·-·-·-·- -·- -·-·- -·-·- -·-·- -·-·- --Q I, 1 11 .I I I I 3 .1 .19.,__ O.ol Percentage oftfme exceeded(%) 8 W.O.7063‐02 BMW Carlsbad HMP Memo December 13, 2019 ATTACHMENT I. Q2 to Q10 Comparison Table – POC 1 Return Period Existing Condition (cfs) Mitigated Condition (cfs) Reduction, Exist ‐ Mitigated (cfs) 2‐year 1.465 0.811 0.654 3‐year 1.820 1.063 0.758 4‐year 1.976 1.381 0.595 5‐year 2.057 1.590 0.467 6‐year 2.227 1.886 0.341 7‐year 2.264 1.965 0.299 8‐year 2.383 2.060 0.324 9‐year 2.490 2.098 0.392 10‐year 2.496 2.196 0.300 ATTACHMENT II FLOW DURATION CURVE ANALYSIS 1)Flow duration curve shall not exceed the existing conditions by more than 10%, neither in peak flow nor duration. The figures on the following pages illustrate that the flow duration curve in post‐development conditions after the proposed BMP is below the existing flow duration curve. The flow duration curve table following the curve shows that if the interval 0.10Q2 – Q10 is divided in 100 sub‐ intervals, then a) the post development divided by pre‐development durations are never larger than 110% (the permit allows up to 110%); and b) there are no more than 10 intervals in the range 101%‐110% which would imply an excess over 10% of the length of the curve (the permit allows less than 10% of excesses measured as 101‐110%). Consequently, the design passes the hydromodification test. It is important to note that the flow duration curve can be expressed in the “x” axis as percentage of time, hours per year, total number of hours, or any other similar time variable. As those variables only differ by a multiplying constant, their plot in logarithmic scale is going to look exactly the same, and compliance can be observed regardless of the variable selected. However, in order to satisfy the City of CarlsbadHMP example, % of time exceeded is the variable of choice in the flow duration curve. The selection of a logarithmic scale in lieu of the normal scale is preferred, as differences between the pre‐development and post‐development curves can be seen more clearly in the entire range of analysis. Both graphics are presented just to prove the difference. In terms of the “y” axis, the peak flow value is the variable of choice. As an additional analysis performed by REC, not only the range of analysis is clearly depicted (10% of Q2 to Q10) but also all intermediate flows are shown (Q2, Q3, Q4, Q5, Q6, Q7, Q8 and Q9) in order to demonstrate compliance at any range Qx – Qx+1. It must be pointed out that one of the limitations of both the SWMM and SDHM models is that the intermediate analysis is not performed (to obtain Qi from i = 2 to 10). REC performed the analysis using the Cunnane Plotting position Method (the preferred method in the HMP permit) from the “n” largest independent peak flows obtained from the continuous time series. The largest “n” peak flows are attached in this appendix, as well as the values of Qi with a return period “i”, from i=2 to 10. The Qi values are also added into the flow‐duration plot. 0.000.200.400.600.801.001.201.401.601.802.002.202.402.600.0003 0.003 0.03 0.3Q (cfs)Percentage of time exceeded (%)BMW Carlsbad POC 1‐Flow Duration CurveExistingProposedQx-.-_, C. i,,--,-. -----·---·--"'"'--------·---·----· --~---------·---__, ,-. --·-Ill.ti 7 ~o 1~· -· ·n·-. , .. ·--· l ·-·-. ----. --. -. •• ~ -·-· ~~ -+ · -·-·-·--· - ---·-·-·--·--· -·,. -. -: l +t ~--·-· ·,· ·-·,·-·,· ·-·-· -·-· -·-~--· -. -·-·-·-··-·--·--· -. --. -i-•-·-·--·--·--. --.. -· ---l I ... .... ~--·-· -·-· -·-·-..... -· .... ""'" -·-·-·-·-·-·--· - -. ----·-·-·--·--· -. --· -. -. g_~ ~5 ..... ~--·-· -·-· -·-·-·--· -· --,-·-·-·-·-·--· - -. ----·-·-·--·--· -. --· -. -. 1 ~ -Qi·-·-· -■-■ -·-·-·-·-·--~--■-■-·--· - -. --. --■-■-■--·--· -·--· -. -. '"' I ~: '-. 1 ...... , \ ~--·-· -·-· -·-·-·-... -· -":"---·-·-·\-·-··--· - -. ---i-•-·-·--·--·· -. --·· -· -• 1 t '\ l. -l "'"' -\ \ ~ \ -·-' I'\. 1 -~ ~r'\. L!LSft-· -· -·-·-·-· -· -· -·-•1-·-·-·-· --~ -·-.... --~ r. --·-·-·-·--·-·-.... -·-- -rt:• (C -~ ' ' 2 .... ~ '-iii. ~-"'I ,0.3~:i-. -·-·-·-· -· -· -·-i-. 1-·-·-·-· -·-· -·-... -i-. ..--\· -·-·-·--·-·-.---·-- -. 1':3( ~"-, " 2 ...... --l...\ .... 0.1-0:,--· -·-·-·-· -· -· -·-i-. 1-·-·-·-· -·-· -·-... -.. -i-. ..---· -·-. --·-·-... -·-- -. 1': .c 2 00.20.40.60.811.21.41.61.822.22.42.600.020.04Q (cfs)Percentage of time exceeded (%)BMW Carlsbad POC 1‐Flow Duration CurveExistingProposedQx-w -. . ·-· . . . ··-~· . . , "4b l i-- - - --· ,_ . --. . --. . -- --- - --· -. --· . --. ·--. -. -- - -r ~ F l-:c ::I : --, . -· ,_ . --. -·-... -. -·r -:c -: I: :::J : -· -. -.... -. --· -. -... -. -:c :I : ----! . =l: ·---. -· ,_ . --. -·-... -. -·-- --· -. -.... -. --· -. -..... -. --...J. l-. c~ '-. ."' - - - --· ,-. --. -·--. -. -- ------· -. -..... -. --· -. -... -. --- - --n. c~ ·---· ---· ,_ . --. -·-... -. -- -----· -· -. -.... -. --· -. -..... -. -·----~ ~3 ,_ -"'~ - - --· ,_ . --. -·-.... -. -- ------· -. -..... -. --· -·-... -. --- - -f.l:: I ~ .._~ ~ \ ci - - -\ --. --. 1-. --· -·-... -·--. - -'" . --,---··-· -. -.... -· -. -n .. -' ... -' ... -·-' ', ' "~ r\_ -"I, ' """"""'---~ -"'.\ .... ~ 1~_5ft. ;---· --· ,-. --. -·--. ,..___ - ------· -. --. -. --· -. -... -. -----n_j~ ' ....... •2-r-,.,._ """""~ -..... ..... .... i-,,.. ..... ...... ----~ !.3'.tt -.. - ---. --. 1-. --· -. -ill..: -·--. -,-,. . --~ il". -· -. -.... -. --· -·-... -·--. --,· --o: ~ 2-i"""o, ......... i"""oi ..._ ..... .... t~.l n -.. - ---. --. 1-. --· ·-... -·--. -,-,. . --.. ,.._ -··-· -. -.... . --· ·-... -. -. r 0 tC., Flow Duration Curve Data for BMW Carlsbad, City of Carlsbad, CA Q2 = 1.47 cfs Fraction 10 % Q10 = 2.50 cfs Step = 0.0237 cfs Count = 499679 hours 57.00 years Pass or Q (cfs) Hours > Q% time Hours>Q % time Post/Pre Fail? 1 0.147 222 4.44E‐02 239 4.78E‐02 108% Pass 2 0.170 206 4.12E‐02 213 4.26E‐02 103% Pass 3 0.194 186 3.72E‐02 191 3.82E‐02 103% Pass 4 0.218 179 3.58E‐02 168 3.36E‐02 94% Pass 5 0.241 175 3.50E‐02 143 2.86E‐02 82% Pass 6 0.265 170 3.40E‐02 118 2.36E‐02 69% Pass 7 0.289 169 3.38E‐02 110 2.20E‐02 65% Pass 8 0.313 164 3.28E‐02 104 2.08E‐02 63% Pass 9 0.336 152 3.04E‐02 99 1.98E‐02 65% Pass 10 0.360 149 2.98E‐02 93 1.86E‐02 62% Pass 11 0.384 146 2.92E‐02 90 1.80E‐02 62% Pass 12 0.408 141 2.82E‐02 84 1.68E‐02 60% Pass 13 0.431 141 2.82E‐02 81 1.62E‐02 57% Pass 14 0.455 135 2.70E‐02 80 1.60E‐02 59% Pass 15 0.479 132 2.64E‐02 79 1.58E‐02 60% Pass 16 0.502 126 2.52E‐02 71 1.42E‐02 56% Pass 17 0.526 121 2.42E‐02 66 1.32E‐02 55% Pass 18 0.550 116 2.32E‐02 64 1.28E‐02 55% Pass 19 0.574 110 2.20E‐02 58 1.16E‐02 53% Pass 20 0.597 106 2.12E‐02 56 1.12E‐02 53% Pass 21 0.621 106 2.12E‐02 53 1.06E‐02 50% Pass 22 0.645 101 2.02E‐02 49 9.81E‐03 49% Pass 23 0.669 99 1.98E‐02 48 9.61E‐03 48% Pass 24 0.692 94 1.88E‐02 46 9.21E‐03 49% Pass 25 0.716 92 1.84E‐02 44 8.81E‐03 48% Pass 26 0.740 89 1.78E‐02 43 8.61E‐03 48% Pass 27 0.763 86 1.72E‐02 41 8.21E‐03 48% Pass 28 0.787 83 1.66E‐02 37 7.40E‐03 45% Pass 29 0.811 81 1.62E‐02 36 7.20E‐03 44% Pass 30 0.835 79 1.58E‐02 32 6.40E‐03 41% Pass 31 0.858 74 1.48E‐02 32 6.40E‐03 43% Pass 32 0.882 72 1.44E‐02 29 5.80E‐03 40% Pass 33 0.906 71 1.42E‐02 28 5.60E‐03 39% Pass 34 0.930 58 1.16E‐02 28 5.60E‐03 48% Pass 35 0.953 58 1.16E‐02 27 5.40E‐03 47% Pass 36 0.977 57 1.14E‐02 26 5.20E‐03 46% Pass Detention Optimized Interval Existing Condition Pass or Q (cfs) Hours > Q% time Hours>Q % time Post/Pre Fail? Detention Optimized Interval Existing Condition 37 1.001 53 1.06E‐02 25 5.00E‐03 47% Pass 38 1.025 53 1.06E‐02 25 5.00E‐03 47% Pass 39 1.048 52 1.04E‐02 24 4.80E‐03 46% Pass 40 1.072 50 1.00E‐02 20 4.00E‐03 40% Pass 41 1.096 50 1.00E‐02 20 4.00E‐03 40% Pass 42 1.119 50 1.00E‐02 19 3.80E‐03 38% Pass 43 1.143 48 9.61E‐03 19 3.80E‐03 40% Pass 44 1.167 47 9.41E‐03 18 3.60E‐03 38% Pass 45 1.191 47 9.41E‐03 18 3.60E‐03 38% Pass 46 1.214 47 9.41E‐03 18 3.60E‐03 38% Pass 47 1.238 43 8.61E‐03 18 3.60E‐03 42% Pass 48 1.262 43 8.61E‐03 18 3.60E‐03 42% Pass 49 1.286 41 8.21E‐03 18 3.60E‐03 44% Pass 50 1.309 37 7.40E‐03 17 3.40E‐03 46% Pass 51 1.333 35 7.00E‐03 17 3.40E‐03 49% Pass 52 1.357 35 7.00E‐03 16 3.20E‐03 46% Pass 53 1.380 35 7.00E‐03 16 3.20E‐03 46% Pass 54 1.404 33 6.60E‐03 15 3.00E‐03 45% Pass 55 1.428 33 6.60E‐03 15 3.00E‐03 45% Pass 56 1.452 33 6.60E‐03 15 3.00E‐03 45% Pass 57 1.475 32 6.40E‐03 15 3.00E‐03 47% Pass 58 1.499 32 6.40E‐03 14 2.80E‐03 44% Pass 59 1.523 31 6.20E‐03 14 2.80E‐03 45% Pass 60 1.547 31 6.20E‐03 14 2.80E‐03 45% Pass 61 1.570 30 6.00E‐03 13 2.60E‐03 43% Pass 62 1.594 29 5.80E‐03 12 2.40E‐03 41% Pass 63 1.618 27 5.40E‐03 11 2.20E‐03 41% Pass 64 1.641 26 5.20E‐03 11 2.20E‐03 42% Pass 65 1.665 25 5.00E‐03 11 2.20E‐03 44% Pass 66 1.689 23 4.60E‐03 11 2.20E‐03 48% Pass 67 1.713 23 4.60E‐03 11 2.20E‐03 48% Pass 68 1.736 23 4.60E‐03 11 2.20E‐03 48% Pass 69 1.760 23 4.60E‐03 11 2.20E‐03 48% Pass 70 1.784 23 4.60E‐03 11 2.20E‐03 48% Pass 71 1.808 23 4.60E‐03 11 2.20E‐03 48% Pass 72 1.831 22 4.40E‐03 11 2.20E‐03 50% Pass 73 1.855 21 4.20E‐03 11 2.20E‐03 52% Pass 74 1.879 19 3.80E‐03 11 2.20E‐03 58% Pass 75 1.903 18 3.60E‐03 10 2.00E‐03 56% Pass 76 1.926 18 3.60E‐03 9 1.80E‐03 50% Pass 77 1.950 18 3.60E‐03 9 1.80E‐03 50% Pass 78 1.974 17 3.40E‐03 9 1.80E‐03 53% Pass 79 1.997 17 3.40E‐03 9 1.80E‐03 53% Pass 80 2.021 16 3.20E‐03 9 1.80E‐03 56% Pass 81 2.045 14 2.80E‐03 9 1.80E‐03 64% Pass Pass or Q (cfs) Hours > Q% time Hours>Q % time Post/Pre Fail? Detention Optimized Interval Existing Condition 82 2.069 12 2.40E‐03 7 1.40E‐03 58% Pass 83 2.092 12 2.40E‐03 7 1.40E‐03 58% Pass 84 2.116 12 2.40E‐03 7 1.40E‐03 58% Pass 85 2.140 10 2.00E‐03 7 1.40E‐03 70% Pass 86 2.164 10 2.00E‐03 7 1.40E‐03 70% Pass 87 2.187 10 2.00E‐03 7 1.40E‐03 70% Pass 88 2.211 10 2.00E‐03 7 1.40E‐03 70% Pass 89 2.235 9 1.80E‐03 6 1.20E‐03 67% Pass 90 2.258 8 1.60E‐03 5 1.00E‐03 63% Pass 91 2.282 8 1.60E‐03 5 1.00E‐03 63% Pass 92 2.306 8 1.60E‐03 5 1.00E‐03 63% Pass 93 2.330 7 1.40E‐03 5 1.00E‐03 71% Pass 94 2.353 7 1.40E‐03 5 1.00E‐03 71% Pass 95 2.377 7 1.40E‐03 5 1.00E‐03 71% Pass 96 2.401 7 1.40E‐03 5 1.00E‐03 71% Pass 97 2.425 7 1.40E‐03 4 8.01E‐04 57% Pass 98 2.448 7 1.40E‐03 4 8.01E‐04 57% Pass 99 2.472 7 1.40E‐03 4 8.01E‐04 57% Pass 100 2.496 6 1.20E‐03 4 8.01E‐04 67% Pass Peak Flows calculated with Cunnane Plotting Position Return Period (years)Pre‐dev. Q (cfs)Post‐Dev. Q (cfs) Reduction (cfs) 10 2.496 2.196 0.300 9 2.490 2.098 0.392 8 2.383 2.060 0.324 7 2.264 1.965 0.299 6 2.227 1.886 0.341 5 2.057 1.590 0.467 4 1.976 1.381 0.595 3 1.820 1.063 0.758 2 1.465 0.811 0.654 ATTACHMENT III List of the “n” Largest Peaks: Pre & Post‐Developed Conditions Basic Probabilistic Equation: R = 1/P R: Return period (years). P: Probability of a flow to be equaled or exceeded any given year (dimensionless). Cunnane Equation:Weibull Equation: Pൌ୧ି.ସ ୬ା.ଶ Pൌ ୧ ୬ାଵ i: Position of the peak whose probability is desired (sorted from large to small) n: number of years analyzed. Explanation of Variables for the Tables in this Attachment Peak: Refers to the peak flow at the date given, taken from the continuous simulation hourly results of the n year analyzed. Posit: If all peaks are sorted from large to small, the position of the peak in a sorting analysis is included under the variable Posit. Date: Date of the occurrence of the peak at the outlet from the continuous simulation Note: all peaks are not annual maxima; instead they are defined as event maxima, with a threshold to separate peaks of at least 12 hours. In other words, any peak P in a time series is defined as a value where dP/dt = 0, and the peak is the largest value in 25 hours (12 hours before, the hour of occurrence and 12 hours after the occurrence, so it is in essence a daily peak). List of Peak events and Determination of Q2 and Q10 (Pre-Development) BMW Carlsbad - POC 1 T (Year) Cunnane (cfs) Weibull (cfs) 10 2.50 2.59 Date Posit Weibull Cunnane 9 2.49 2.49 0.908 1/15/1978 57 1.02 1.01 8 2.38 2.44 0.923 9/18/1963 56 1.04 1.03 7 2.26 2.29 0.923 1/11/2005 55 1.05 1.05 6 2.23 2.23 0.926 3/15/1986 54 1.07 1.07 5 2.06 2.07 0.926 12/24/1988 53 1.09 1.09 4 1.98 1.99 0.927 2/19/1958 52 1.12 1.11 3 1.82 1.82 0.929 1/6/1979 51 1.14 1.13 2 1.47 1.47 0.986 8/17/1977 50 1.16 1.15 0.992 2/22/1998 49 1.18 1.18 0.992 2/12/2003 48 1.21 1.20 Note:0.994 11/8/2002 47 1.23 1.23 Cunnane is the preferred 1.039 12/31/2004 46 1.26 1.25 method by the HMP permit. 1.053 2/4/1994 45 1.29 1.28 1.069 3/1/1991 44 1.32 1.31 1.123 11/11/1985 43 1.35 1.34 1.137 4/27/1960 42 1.38 1.38 1.157 2/14/1998 41 1.41 1.41 1.226 1/18/1993 40 1.45 1.44 1.237 12/2/1961 39 1.49 1.48 1.277 2/12/1992 38 1.53 1.52 1.292 2/15/1986 37 1.57 1.56 1.296 3/2/1980 36 1.61 1.61 1.304 1/16/1978 35 1.66 1.65 1.304 1/29/1980 34 1.71 1.70 1.32 3/11/1995 33 1.76 1.75 1.325 1/6/2008 32 1.81 1.81 1.394 12/30/1991 31 1.87 1.87 1.394 2/17/1998 30 1.93 1.93 1.465 1/27/2008 29 2.00 2.00 1.512 2/23/1998 28 2.07 2.07 1.59 10/20/2004 27 2.15 2.15 1.595 2/16/1980 26 2.23 2.23 1.611 2/10/1978 25 2.32 2.33 1.627 11/22/1965 24 2.42 2.42 1.664 2/27/1983 23 2.52 2.53 1.667 1/29/1983 22 2.64 2.65 1.667 2/3/1998 21 2.76 2.78 1.808 3/17/1982 20 2.90 2.92 1.832 1/16/1952 19 3.05 3.08 1.856 11/15/1952 18 3.22 3.25 1.864 12/19/1970 17 3.41 3.45 1.879 10/27/2004 16 3.63 3.67 1.958 4/1/1958 15 3.87 3.92 2.021 1/14/1993 14 4.14 4.21 2.034 3/1/1978 13 4.46 4.54 2.046 2/20/1980 12 4.83 4.93 2.12 2/18/2005 11 5.27 5.40 2.227 10/29/2000 10 5.80 5.96 2.235 2/25/1969 9 6.44 6.65 2.309 2/4/1958 8 7.25 7.53 2.488 9/23/1986 7 8.29 8.67 2.497 2/25/2003 6 9.67 10.21 3.025 1/4/1995 5 11.60 12.43 3.175 1/15/1979 4 14.50 15.89 3.525 1/4/1978 3 19.33 22.00 3.541 10/1/1983 2 29.00 35.75 3.911 4/14/2003 1 58.00 95.33 Peaks (cfs) Period of Return (Years) List of Peak events and Determination of Q2 and Q10 (Post‐Development) BMW Carlsbad ‐ POC 1 T (Year) Cunnane (cfs) Weibull (cfs) 10 2.20 2.22 Date Posit Weibull Cunnane 9 2.10 2.14 0.233 1/14/1993 57 1.02 1.01 8 2.06 2.06 0.237 12/17/1987 56 1.04 1.03 7 1.97 2.01 0.237 10/29/2000 55 1.05 1.05 6 1.89 1.89 0.238 3/2/1983 54 1.07 1.07 5 1.59 1.59 0.238 10/12/1987 53 1.09 1.09 4 1.38 1.41 0.239 2/14/1954 52 1.12 1.11 3 1.06 1.07 0.242 1/6/1977 51 1.14 1.13 2 0.81 0.81 0.243 12/19/1967 50 1.16 1.15 0.243 2/18/2005 49 1.18 1.18 0.271 9/23/1986 48 1.21 1.20 Note: 0.359 4/1/1958 47 1.23 1.23 Cunnane is the preferred 0.372 10/20/2004 46 1.26 1.25 method by the HMP permit. 0.375 1/15/1993 45 1.29 1.28 0.376 1/11/2005 44 1.32 1.31 0.394 12/29/2004 43 1.35 1.34 0.426 1/27/1956 42 1.38 1.38 0.482 12/25/1983 41 1.41 1.41 0.483 1/18/1952 40 1.45 1.44 0.502 1/16/1952 39 1.49 1.48 0.503 2/18/1980 38 1.53 1.52 0.514 1/11/1980 37 1.57 1.56 0.562 1/18/1993 36 1.61 1.61 0.58 10/27/2004 35 1.66 1.65 0.617 1/22/1967 34 1.71 1.70 0.624 3/3/1983 33 1.76 1.75 0.637 1/25/1969 32 1.81 1.81 0.751 3/11/1995 31 1.87 1.87 0.759 11/22/1996 30 1.93 1.93 0.811 12/5/1966 29 2.00 2.00 0.814 1/20/1962 28 2.07 2.07 0.824 3/5/1995 27 2.15 2.15 0.866 11/30/2007 26 2.23 2.23 0.905 1/16/1993 25 2.32 2.33 0.947 1/9/2005 24 2.42 2.42 0.998 1/13/1997 23 2.52 2.53 1.033 2/23/2005 22 2.64 2.65 1.05 3/8/1968 21 2.76 2.78 1.054 1/15/1978 20 2.90 2.92 1.071 1/6/1979 19 3.05 3.08 1.1 2/15/1986 18 3.22 3.25 1.149 2/22/2008 17 3.41 3.45 1.299 3/1/1991 16 3.63 3.67 1.336 1/16/1978 15 3.87 3.92 1.494 2/23/1998 14 4.14 4.21 1.56 1/29/1980 13 4.46 4.54 1.588 11/22/1965 12 4.83 4.93 1.6 3/17/1982 11 5.27 5.40 1.885 2/20/1980 10 5.80 5.96 1.905 3/1/1978 9 6.44 6.65 2.056 2/25/1969 8 7.25 7.53 2.065 2/4/1958 7 8.29 8.67 2.217 2/25/2003 6 9.67 10.21 2.237 1/4/1978 5 11.60 12.43 2.606 10/1/1983 4 14.50 15.89 2.766 1/15/1979 3 19.33 22.00 3.323 1/4/1995 2 29.00 35.75 3.7 4/14/2003 1 58.00 95.33 Peaks (cfs) Period of Return (Years) ATTACHMENT IV AREA VS ELEVATION The storage provided beneath the first surface outlet by the LID BMP is entered into the LID Module within SWMM – please refer to Attachment VII for further information. The surface bio‐ filtration BMPs are bordered by vertical walls, as such the area is constant with depth. Similarly, the underground detention vault has a constant area as the depth increases due to it being a walled structure. DISCHARGE VS ELEVATION The orifices have been selected to maximize their size while still restricting flows to conform with the required 10% of the Q2 event flow as mandated in the Final Hydromodification Management Plan by Brown & Caldwell, dated March 2011. While REC acknowledges that these orifices are small, to increase the size of these outlets would impact the basin’s ability to restrict flows beneath the HMP thresholds, thus preventing the BMP from conformance with HMP requirements. In order to further reduce the risk of blockage of the orifices, regular maintenance of the riser and orifices must be performed to ensure potential blockages are minimized. A detail of the orifice and riser structure is provided in Attachment V of this memorandum. The LID low flow orifice discharge relationship is addressed within the LID Module within SWMM – please refer to Attachment VII for further information. DISCHARGE EQUATIONS 1)Weir: ܳௐ ൌ ܥௐ ܮܪଷ/ଶ (1) 2)Slot: As an orifice: ܳ௦ ൌܤ௦ ݄௦ ܿ ට2݃ ቀܪെೞ ଶ ቁ (2.a) As a weir: ܳ௦ ൌܥௐ ܤ௦ ܪଷ/ଶ (2.b) For H > hs slot works as weir until orifice equation provides a smaller discharge. The elevation such that equation (2.a) = equation (2.b) is the elevation at which the behavior changes from weir to orifice. 3)Vertical Orifices As an orifice: ܳ ൌ0.25ߨܦଶ ܿ ට2݃ ቀܪെ ଶቁ (3.a) As a weir: Critical depth and geometric family of circular sector must be solved to determined Q as a function of H: ܳைଶ ݃ ൌ ܣଷ ܶ ; ܪ ൌ ݕ ܣ 2ܶ ; ܶ ൌ2ඥݕሺܦെݕሻ ; ܣ ൌ ܦଶ 8 ሾߙ െݏ݅݊ሺߙሻሿ ; ݕ ൌ ଶ ሾ1െݏ݅݊ሺ0.5 ߙሻሿ (3.b.1, 3.b.2, 3.b.3, 3.b.4 and 3.b.5) There is a value of H (approximately H = 110% D) from which orifices no longer work as weirs as critical depth is not possible at the entrance of the orifice. This value of H is obtained equaling the discharge using critical equations and equations (3.b). A mathematical model is prepared with the previous equations depending on the type o discharge. The following are the variables used above: QW, Qs, QO = Discharge of weir, slot or orifice (cfs) CW, cg : Coefficients of discharge of weir (typically 3.1) and orifice (0.61 to 0.62) L, Bs, D, hs : Length of weir, width of slot, diameter of orifice and height of slot, respectively; (ft) H: Level of water in the pond over the invert of slot, weir or orifice (ft) Acr, Tcr, ycr, αcr: Critical variables for circular sector: area (sq‐ft), top width (ft), critical depth (ft), and angle to the center, respectively. Outlet structure for Discharge of Underground Vault Discharge vs Elevation Table Low orifice:1.125 " Lower slot Emergency Weir Number: 1 Invert: 0.00 ft Invert: 7.208 ft Cg‐low: 0.61 B 0.00 ft B: 5 ft Middle orifice:1 " h 0.000 ft number of orif: 0 Upper slot Cg‐middle: 0.62 Invert: 0.000 ft invert elev: 0.25 ft B: 0.00 ft h 0.167 ft h H/D‐low H/D‐mid Qlow‐orif Qlow‐weir Qtot‐low Qmid‐orif Qmid‐weir Qtot‐med Qslot‐low Qslot‐upp Qemer Qtot (ft)‐‐(cfs) (cfs)(cfs)(cfs) (cfs)(cfs) (cfs) (cfs) (cfs) (cfs) 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.250 2.667 0.000 0.015 0.019 0.015 0.000 0.000 0.000 0.000 0.000 0.000 0.015 0.500 5.333 3.000 0.023 0.202 0.023 0.000 0.000 0.000 0.000 0.000 0.000 0.023 0.750 8.000 6.000 0.028 0.283 0.028 0.000 0.000 0.000 0.000 0.000 0.000 0.028 1.000 10.667 9.000 0.033 0.330 0.033 0.000 0.000 0.000 0.000 0.000 0.000 0.033 1.250 13.333 12.000 0.037 0.371 0.037 0.000 0.000 0.000 0.000 0.000 0.000 0.037 1.500 16.000 15.000 0.041 0.407 0.041 0.000 0.000 0.000 0.000 0.000 0.000 0.041 1.750 18.667 18.000 0.044 0.441 0.044 0.000 0.000 0.000 0.000 0.000 0.000 0.044 2.000 21.333 21.000 0.047 0.472 0.047 0.000 0.000 0.000 0.000 0.000 0.000 0.047 2.250 24.000 24.000 0.050 0.502 0.050 0.000 0.000 0.000 0.000 0.000 0.000 0.050 2.500 26.667 27.000 0.053 0.529 0.053 0.000 0.000 0.000 0.000 0.000 0.000 0.053 2.750 29.333 30.000 0.056 0.556 0.056 0.000 0.000 0.000 0.000 0.000 0.000 0.056 3.000 32.000 33.000 0.058 0.581 0.058 0.000 0.000 0.000 0.000 0.000 0.000 0.058 3.250 34.667 36.000 0.060 0.605 0.060 0.000 0.000 0.000 0.000 0.000 0.000 0.060 3.500 37.333 39.000 0.063 0.628 0.063 0.000 0.000 0.000 0.000 0.000 0.000 0.063 3.750 40.000 42.000 0.065 0.650 0.065 0.000 0.000 0.000 0.000 0.000 0.000 0.065 4.000 42.667 45.000 0.067 0.672 0.067 0.000 0.000 0.000 0.000 0.000 0.000 0.067 4.250 45.333 48.000 0.069 0.693 0.069 0.000 0.000 0.000 0.000 0.000 0.000 0.069 4.500 48.000 51.000 0.071 0.713 0.071 0.000 0.000 0.000 0.000 0.000 0.000 0.071 4.750 50.667 54.000 0.073 0.733 0.073 0.000 0.000 0.000 0.000 0.000 0.000 0.073 5.000 53.333 57.000 0.075 0.752 0.075 0.000 0.000 0.000 0.000 0.000 0.000 0.075 5.250 56.000 60.000 0.077 0.771 0.077 0.000 0.000 0.000 0.000 0.000 0.000 0.077 5.500 58.667 63.000 0.079 0.789 0.079 0.000 0.000 0.000 0.000 0.000 0.000 0.079 5.750 61.333 66.000 0.081 0.807 0.081 0.000 0.000 0.000 0.000 0.000 0.000 0.081 6.000 64.000 69.000 0.082 0.824 0.082 0.000 0.000 0.000 0.000 0.000 0.000 0.082 6.250 66.667 72.000 0.084 0.842 0.084 0.000 0.000 0.000 0.000 0.000 0.000 0.084 6.500 69.333 75.000 0.086 0.858 0.086 0.000 0.000 0.000 0.000 0.000 0.000 0.086 6.750 72.000 78.000 0.087 0.875 0.087 0.000 0.000 0.000 0.000 0.000 0.000 0.087 7.000 74.667 81.000 0.089 0.891 0.089 0.000 0.000 0.000 0.000 0.000 0.000 0.089 7.208 76.885 83.496 0.090 0.904 0.090 0.000 0.000 0.000 0.000 0.000 0.000 0.090 7.500 80.000 87.000 0.092 0.923 0.092 0.000 0.000 0.000 0.000 0.000 2.442 2.534 7.750 82.667 90.000 0.094 0.938 0.094 0.000 0.000 0.000 0.000 0.000 6.180 6.273 8.000 85.333 93.000 0.095 0.953 0.095 0.000 0.000 0.000 0.000 0.000 10.919 11.014 ATTACHMENT V Pre & Post‐Developed Maps, Project Plan and Detention Section Sketches l . 1 I i j lEEtm RIVERS/CREEKS WATERSHEDS ~RECIPIT~:TICH 0 UE INCLUDE, ST,i.110NooI~OOIFICA110N IN HY O o SET RAINFALL DATA OlHER ALERT STAllO~ " L. ,-.f, l.l..F l 1, • • t, ~ \ ,•~\ , •-• • :~ 1\1_00~. \ ·• ~- l .. ,i -~ \:\ • .. \ ~' CANN~N ROAD • • ~ C/2 L -• ' • \ ·•: •. •• 11W --\9, c..> \ E::7 --------- • • ?=:' '-----1\' "-v"---. ---"----,9 5"_ "-C/2 ENTIRE SITE ULTIMATELY "~ --~ 1--....___ ~-' \.. -DISCHARGES TO CITY'S ----------SD SYSTEM. I,\ II \9" K -~ ' --POC #1 __,,....__\_,___ll'.'..J'I-ROOF DOWN DRAIN TO BMP-3 ------- > DMA-1 C ,___ _ 1.2 I ~---~---~----,-STRUCTURAL BMP-6B: ~ UNDERGROUND DETENTION SYSTEM FOR ROOF STORM DRAIN SYSTEM PER MEP PLANS I STRUCTURAL BMP-5: ~= PROPRIETARY BIOFILTRATION (BF-3) FOR ------------- S'iOP / • I • • STRUCTURAL BM P-6A: UNDERGROUND DETENTION SYSTEM FOR HYDROMODIFI CATION MANAGEMENT (HYDRAU LICALLY CONNECTED TO BMP-6B) 0 a :11' j ROOF RUNOFF POLLUTANT CONTROL 0 ROOF DOWN --DRAIN TO BMP-5 ROOF STORM DRAIN SYSTEM PER MEP PLANS Ir◊ L t CAR RAMP FLOWS TO DMA-1C 0 ~ ---- ROOF DOWN DRAIN TO BMP-5 0 ---- ROO F STORM DRAIN SYSTEM PER MEP PLANS ( \ I I '&, I d---as --r ~ ~--...--..... 1 ' ,c,I / / / 1.2 )- 0 0 DMA-1 D STRUCTURAL BMP-4: BIOFILTRATION (BF-1) FOR POLLUTANT CONTROL AND HYDROMODIFICATION 0 MANAGEMENT I../ ~--~~--~--- ROOF STORM DRAIN SYSTEM PER MEP PLANS i SD ---- L SD ----SD ---- SD ---- ---- SD ---- HYDROMODIFICATION MANAGEMENT (HYDRAULICALLY CONN ECTED TO BMP-6A) PROPOS ED BUILDING W/ ROOFTOP PARKING ---- +------ 'I ---- LJ ---- ---- ,, ___ _ SD ---- 1.5 1.5 - 1.4 \ ------" 1.5 -., ~ --------- . . . 4_· .• ><·-e·" _;. r\ STRUCTURAL BMP-1 : BIOFILTRATION W/ PARTIAL RETENTION (PR-1 ) FOR POLLUTANT CONTROL AND HYDROMODIFICATION MANAGEMENT SD -----$TI ---- SD SD 103 t ---- LJ STRUCTURAL BMP-2: BIOFILTRATION W/ PARTIAL RETENTION (PR-1 ) FOR POLLUTANT CONTROLAND HYDROMODIFICATION MANAGEM ENT 1.5 - ---- ti\ I I I I \ \ • :~ ~I \ \ : ~ IH+l=id=l---i!./---IJ--I/ 1.5 I I I I I \ ~ \ \ I -=r ) I I I l I \ \ I I LEGEND: ASPHALT (IMPERVIOUS) ----PROPERTY LIN E ' • • CONCRETE (IMPERVIOUS) SURFACE FLOW DIRECTION I I I I I I PERMEABLE PAYERS -SD-PROPOSED STORM DRAIN SYSTEM LANDSCAPE (□MA#) DMA ID ROOF AREA 0 OMA SUB-AREA ID MAJOR OMA BO UNDARY -GD-PROPOSED CONTOUR ----SUB-OMA BOUNDARY -#-EXISTING CONTOUR f I BIOFILTRATI ON BAS IN IW//~I UNDERGROUND DETENTI ON VAULT (W/ PARTIAL RETENTION) liiiw:#w:#~ PROPRIETARY BIOFILTRATION DEVICE BIOFILTRATI ON BAS IN ~I (W/ IMPERMEABLE LINER) PORCELAIN TILE GEOTECHNICAL INFO: • HYDROLOGIC SOIL GROUP B • INFILTRATI ON : 0.041 IN/HR • SOIL EXPANSIVE POTENTIAL: VERY LOW • DEPTH TO GROUNDWATER >50' CCSYAANALYSIS: NO CRITICAL COURSE SEDIMENT YIELD AREAS TO BE PROTECTED BAS ED ON WMAA MAPS. BMP DETAILS: SEE LID BMP DETAILS IN ATTAC HMENT 1 E OF SWOMP. OMA SUMMARY: Post-Develooed Condition OMA Area Area Type ID (SF} (AC} DMA-lA ➔ BIOFILTRATION W/ RETENTION ➔ POC #1 1.1 Roof/Pavement 19,664 0.451 1.2 Landscape (B, 0-5%) 2,314 0.053 1.3 Landscape (B, 5-15%) 520 0.012 1.4 Landscape (B, >15%} 387 0.009 1.5 Permeable Pavers 9,589 0.220 ------·-l: 32,474 0.746 DMA-1B ➔ BIOFILTRATION W/ RETENTION ➔ POC #"1 1.1 Roof/Pavement 8,486 0.195 1.2 Landscape (B, 0-5%) 1,281 0.029 1.3 Landscape (B, 5-15%) 1,030 0.024 1.4 Landscape (B, >15%) 3,765 0.086 LS Permeable Pavers 3,874 0.089 --------------------------------------·-----cc---c'c-ccc··-----------------l: 18,436 0.423 DMA-lC ➔ BIOFILTRATION BASIN ➔ POC #1 1.1 Roof/Pavement 1.2 Landscape (B, 0-5%) 21,181 1,466 L 22,647 OMA-10 ➔ BIOfllTRATION BASIN ➔ POC #1 1.1 Roof/Pavement 13,935 1.2 Landscape (B, 0-5%} 1,117 1.3 Landscape (B, 5-15%) 230 0.486 0.034 0.520 0.320 0.026 0.005 1.5 Permeable Pavers 2,312 0.053 -----------------------------------------------------------------I 17,594 o.404 DMA-lE ➔ PROPRIETARY BIOFILT. (MWS) ➔ POC #1 1.1 Roof/Pavement 57,558 L 57,558 DMA-1 TOTAL 148,710 DMA-2A ➔ SELF-MITIGATING AREA ➔ POC #1 2.1 Roof/Pavement 110 2.2 Landscape (B, 5-15%) 658 1.321 1.321 3.414 0.003 0.015 _____ ?~~-----Landscape~(B_, >_1_5o/c_,) ____ 12_,0 ___ 2s _________ 9~?-~? ___ _ I 12,793 0.294 DMA-2 TOTAL 12,793 0.294 POC #1 TOTAL 161,503 3.708 20 0 20 GRAPHIC SCALE SCALE: 1"= 20' 40 -C 0 E L u 0 --4 I m rn 0 rn ;;- Q_ :, a 3 '" / 4 u ~ 0 ~ m 0 u 31 :, rn, C 0 -0 z -------------------------------------------------------1.s PREPARED FOR: PREPARED BY: " 4, SWQMP ATTACHMENT IA: DMAEXHIBIT + u fr" AU TONATION INC. ;;_ '" 200 SW 1ST STREET, 14TH FLOOR m' FORT LAUDERDALE, FL 33301 Commercial --------------------;~ ~ I CONTACT CLIFF POWELL Development BMW OF CARLSBAD ~ ':11 " • TEL (954) 759 .. 5000 Resources ~- AUTO CENTER CT / / / ' · Today's Ideas Tomorrow's Reality 1060 AUTO CENTER COURT -tJ _j -s=~'"v':. ~ / ··"' 4121 Westerly Place #11 2 Nev11port8eachCA92660 CARLSBAD, CA 92008 t I / 'fP T 949 -610-8997 www.CDRwest.com ~ ~L ___________________________ ....;:..::..::;;;;;;;.;;;;;;........, __________________ ___;1 ____ -'---------';_ _____ ___..~~~--_;_---..l.----------------------...L---------------~~ _j 2 U) _J ~ w 0 ~ w 1---U) >-U) z 0 1-z w 1-w 0 U) _J ~ w 0 z U) <C co RISER INFORMATION STUB INFORMATION BM P-6A: PIECE RIM ELEV. SYSTEM PIECE STUB INVERT SYSTEM INVERT INVERT WEST OF PR OPOSED BUILDING 4'-0" 36"0 RISER A3 '" f ~ A 96"0BULKHEAO A1 W/ 12"0 STUB A2a THE UNDERSIGNED HEREBY APPROVES THE ATTACHED (4) PAGES INCLUDING THE FOLLOWING: • PIPE STORAGE = 5,681 CF • MAINLINE PIPE GAGE= 16 • WALL TYPE = SOLID • DIAMETER = 96" • FINISH= ALT2 • CORRUGATION= 5x1 CUSTOMER DATE Tte 1os~c. oc,J h,'crc-ctba slocw" en lh, de"''•'"" Is pm,;cl,d ", ser,;co lO ,no C<<;oct ,,.,,,,., '"""'" ..-d x.,1,acror"' G,.--,, Eo~"'"""" S,,·,.,~,,, U.G i'ICootech''.,. N,;,n,, lh" O,awlcs, ao· aa, "'"·"""''JI . .,,,,."' u,,c, ""'"'"""'" oc m:,;rt.eo ,n ,,., mon•ecw101o·Jtu-.e oror , .• ,"~' ,~os ot Ce'lt«.,. Fcll,r<iOCO~otl" ,,.., """ """ ,wo,51< '"' c,_h ""°'"'~' ,aoam, ,,, , ,hJ~· o, ,.,,r,on,lhify foe '"'''"'" 11 ,~erc,,ando, "''""'" '" '""''"" '"°'"""'" cooo ~, o-;i-o o,.,,,,,, 1, °"'"° ,n; ,du~ fi""1 oooca:oas ""' '"''""'"''' "''" ''•""' °'°'""""· '""'• ,1,0-,,,,ncia, most c, ""°""' co u,,_ 1m""'"'"~ ro, re·e\"elJ;)'"" or"" ""~"· c"'"'"' aoceots n, llabllt)• focc;,s·aos ""'' en mlss:ao, ~romp.,,. cr ;,-,"'"''";''"""'"""'''''"'''"''""'' MAR~ DATE REVISION DESCRIPTION BY HOT-DIP GALVAN IZED PLATE GREATER THAN UNDERDRAIN WI DRILLED HOLE ½" DIA. OPENING 4" INVERT OF 6" DIA. SLOTTED PVC UNDERDRAIN -BOTTOM OF BASI N FLOW CONTROL ORIFICE PLATE C I BAND, TYPICAL SEE DETAIL SHEET P3 C(~NTECH" ENGINEERED SOLUTIONS LLC www.ContechES.com 11815 NE Glenn Widing Drive. Portland, OR 97220 800-548-4667 503-240-3393 SU0-561-1 271 FAX 6" DIA. SLOTTED PVC UNDERDRAIN RISER WALL FLOW CONTROL ORIFICE PLATE, SEE DETAIL ABOVE BOTTOM OF BASIN \ NATURAL SOIL LID ORIFICE DETAIL AM ENDED 6" DIA SLOTTED = i ¼" DIA ORIFICE { 4" SOIL MEDIA PVC UNDERDRAIN «Y/_,,(<, '/,t(",'./(' -~'0'v«, ! >0 »;;;;»0_;~-d'$,:2$;»;$'f; f 3' SAND FILTER COURSE ____ 0 _____ 0 -~--- 0 __ --~ __ f,', PEA GRAVEL GRAVEL STORAGE O O o O o O o O 6 0 0 0 0 BOTTOM OF BASIN NATURAL SOIL 36"0 RISER A3 TBD 87.00 12"0 STUB A2 94.00 87.00 12"0 STUB B2 87.00 87,00 10"0 STUB 83 94.17 87.00 113'-0" I I I I I I I C C I B I I I I 96"0 BULKHEAD B1 I : W/ 12"0 STUB 82 f 4'-0" 10"0 STUB 83 NOTES • BULKHEADS SHALL BE 12-GAGE OR HEAVIER STEEL AND THE COATING WILL MATCH THE SPECIFIED CMP COATING. BULKHEAD PLATES SHALL BE FULLY WELDED ONTO THE CMP WITH STEEL REINFORCEMENT AS REQUIRED. THE STEEL REINFORCEMENT SHALL BE POST COATED WITH ZINC RICH PAINT PER AASHTO M 36. BULKHEAD DESIGNS SHALL SATISFY THE REQUIREMENTS SHOWN IN CHAPTER 8 OF THE NCSPA CSP DESIGN MANUAL AND CALCULATIONS SHALL BE PROVIDED TO THE ENGINEER OF RECORD (EOR) FOR APPROVAL UPON REQUEST ASSEMBLY • ALL FITTINGS SHALL BE STRUCTURALLY CHECKED FOR REINFORCEMENTS PER ASTM A998 AND PROVIDED TO THE EOR FOR APPROVAL UPON REQUEST SCALE: 1" = 10' • CONNECTING BANDS FOR DETENTION SYSTEMS SHALL BE HUGGER TYPE OR FULLY PIPE STORAGE : 5,681 CF CORRUGATED WITH APPROPRIATE BOLTED CONNECTIONS THAT CAN BE TORQUED TO 35 FOOT LOADING: H20 POUNDS. BANDS SHALL MATCH THE SPECIFIED CMP COATING AND MEET THE REQUIREMENTS PIPE INV.= 87.00'± OF AASHTO M 36. • All METALLIC COATINGS AFFECTED BY MANUFACTURING FABRICATION SHALL BE REPAIRED PER AASHTO M 36 SECTION 11 REQUIREMENTS (E.G. ZINC-RICH PAINT ON ALL WELDS) IF POLYMER COATINGS ARE USED THE REPAIR OF DAMAGED COATINGS WILL BE IN CONFORMANCE WITH AASHTO M 245 SECTION 11 REQUIREMENTS. • ACCESS LADDERS SHALL BE ATTACHED BY THE MANUFACTURER PRIOR TO DELIVERY, NOT INSTALLED ON THE JOBSITE. _,,11,:.auTr-u· 96"0 UNDERGROUND DETENTION SYSTEM -617515-010 ~~~ i I.V!"!! PROJECT No.: ISEQ. No.: I D/\TE 617515 010 5118/2021 CMP DETENTION SYSTEMS BMW CARLSBAD CARLSBAD , CA I CONTECH I PROPOSAL SITE DESIGNATION: BMP 6A DRAWING HOT-DIP GALVANIZED PLATE GREATER THAN UNDERDRAIN W/ DRILLED HOLE ¾" DIA OPENING 3" INVERT OF 6" DIA. SLOTTED PVC UNDERDRAIN ~ BOTTOM OF BASIN FLOW CONTROL ORIFICE PLATE LI D ORIFICE DETAIL AM ENDED 6" DIA SLOTTED SOIL MEDIA~' PVC UNDERDRAIN ij>-«-. '/A"«· -,;e/./''"« >"">-°'»'»70;.,_-:::f:,0;; --!-_-:::f;,"'»"-"'»;$'f; ! FILTER COURSE!' · ' ·. ·.>--·a'\ ' 3"SAND 3" PEA GRAVEL o O O O 0 GRAVEL STORAGE ) 0 0 ° 0 0 ° o O O o O ( 6' "/ ,,<'(\ IMPERMEABLE LINER AT BOTTOM OF BASIN \ NATURAL TO BE 30 MIL GSE HD SMOOTH LINER BY GSE SOIL ENVIRONM ENTAL OR APPROVED EQUIVALENT PLACEMENT OF SLOTTED UNDERDRAIN BMP-3 /]iliiiR I I · I t1 J I l , I I.- _l I l. - I ll J I DESIGNED RLH CHECKED SHEET NO P1 BMP-4 RISER DRAWN RLH APPROVED Ce 4 HORIZONTAL 6" DIA. SLOTTED PVC UNDERDRAIN C.O. BMP-4 BMP-6B: NORTH OF PROPOSED 4'-0" 36"0 RISER A4 96"0BULKHEADA1 / WI 12"0 STUB A2 WI 10"0 STUB A3 THE UNDERSIGNED HEREBY APPROVES THE ATTACHED {4) PAGES INCLUDING THE FOLLOWING: • PIPE STORAGE= 4,776 CF • MAINLINE PIPE GAGE= 16 • WALL TYPE = SOLID • DIAMETER = 96" • FINISH= ALT2 • CORRUGATION = 5x1 CUSTOMER DATE Tho do,,1., ac.1 ,Fonnocloo ,oo,,~ "' 1"1< <lmwlcs ls p<.,·,~c.<I "" '"''"' '" "'" µ,u);Cl """"· ,,,,;,~" """ co,,O<>Olc, ,, '.¼,ta,J, E,-~;,,,..o,,1 Sc.l,~o·" lLr-fG""1""1'>. N~he, 11-is dca,,aa. noc ,..,. ca1 Che,acl, m,, be"""· a,pwdococ oc n·o,,ni,,;, In Cll\' rno,n" ½11"°"' 1t>e OrlOC wrtt<n "'"""' o' Conte<h •• 0,·1-,01<> "'"""'' ;, oono at Lt>o ·.socs o,-·n M,K an, Gootech "'"""'' o;,,,,1,;,,, ")' llsblllc' n· .,.,s,,,nabllll; fee ''""""' tr "'"''""""' M'.wecn 1"' sc,o:IO<l lnloc..,,on u,:,:,n "~'" to. ,,.,.,;no 1, ,.,., aco ,ctu,1 ••Id c,,::dt&, ,., .,,,ecol,,.., ,a '"' ~o-, '"''"'"""· u-,e,e ""'""""' ,, mu,< bO ""'""' to un1ecn lmmMIO:~vt<r ro,ovOlcaron 01 ,no"'""· c:on1ecn """'" oo lla,1111,,.,,-des<>'s Cased ,a m~i,g, 1,00m,le1e ,c ;""""""'' """""":'"""'"'·";"'; """" MARf DATE REVISION DESCRIPTION BMP-1 RISER _____ -__________ ,:_ __ 7 ·' ...... ·.,· . ·. . . ' ., NOTE UNDERDRAIN ENTERS RISER AT ONLY 1 (ONE) SIDE BMP-2 RISER BMP-2 HORIZONTAL 6" DIA SLOTTED PVC UNDERDRAIN co l : I I I I I I .I I : I t l I BMP-1 PLAC EMENT OF SLOTTED UNDERDRAIN BASIN BMP RISER & SLOTTED UNDERDRAIN C.O. LAYOUT RETAINING WALL 3.33' VARIES PER PLAN 3'x3' RISER -(2'x2' INTERNALLY) OUTLET PIPE PER PLAN NOTE: SLOTTED UNDERDRAIN AND ORIFICE OUTLET NOT SHOWN TYPICAL BASIN CROSS-SECTI ON RETAINING WALL 6" FREEBOARD 6" PONDING 3" MULCH 18" AMENDED SOIL 3" SAND (FILTER) 3" PEA GRAVEL (FILTER) 7" GRAV EL (STORAG E) BMP-1 & BMP-2: BIOFILTRATION BASIN W/ PARTIAL RETENTION VARIES PER PLAN RETAINING WALL RETAINING WALL 3.25' NOTE 3'x3' RISER -(2'x2' INTER NALLY) ·~-'v Yi ,✓,. (%JTl'.'.ET " PIPE IMPERMEABLE LINER. SEE NOTES 1. SLOTTED UNDERDRAIN AND OR IFICE OUTLET NOT SHOWN 2. IMPERMEABLE LINER TO BE 30 MIL GSE HD SMOOTH LINER FROM GSE ENVIRONM ENTAL OR APPROVED EQU IVALENT TYPICAL BAS IN CROSS-SECTION 6" FREEBOARD 6" PONDING 3" MULCH 18" AMENDED SOIL 3" SAND (FILTER) 3" PEA GRAVEL (FILTER) 6" GRAVEL (STORAG E) BMP-3 & BMP-4: BIOFIL TRATION BASIN W/ IMPERMEABLE LINER cl C n I 6" DIA. SLOTTED PVC UNDERDRAIN \ ~" 9 .. p ' 0 0 o . 0 i, 0 O G if ORIFICE Vi PLATE n -- OUTFALL PIPE SIZE & , • LOCATION PER PLAN ,,,,---- BASIN BMP RISER OUTLET DETAIL 0 , 6" PVC SCREW CAP / WATERTIGHT CAP ON TERMINAL END OF PIPE 6" DIA SLOTTED PVC UNDERDRAIN CONN ECTED TO DOWNSTREAM CLEANOUT OR SQUARE RISER UNDERDRAIN CLEANOUT (C .O.) DETAIL STUB INFORMATION PIECE STUB INVERT SYSTEM INVERT BUILDING 12"0 STUB A2 87.00 87.00 10"0 STUB A3 94.17 87.00 12"0 STUB B2 94.00 87_00 RISER INFORMATION PIECE RIM ELEV SYSTEM INVERT 95'-0" 36"0 RISER A4 TBD 87.00 ,, I I I I I I I I I ~ 96"0 BULKHEAD 8 1 A I C I C I B I I I I I I I I I ,, WI 12"0 STUB B2 BAND, TYPICAL SEE DETAIL SHEET P3 NOTES • BULKHEADS SHALL BE 12-GAGE OR HEAVIER STEEL AND THE COATING WILL MATCH THE SPECIFIED CMP COATING. BULKHEAD PLATES SHALL BE FULLY WELDED ONTO THE CMP WITH STEEL REINFORCEMENT AS REQUIRED. THE STEEL REINFORCEMENT SHALL BE POST COATED WITH ZINC RICH PAINT PER AASHTO M 36. BULKHEAD DESIGNS SHALL SATISFY THE REQUIREMENTS SHOWN IN CHAPTER 8 OF THE NCSPA CSP DESIGN MANUAL AND CALCULATIONS SHALL BE PROVIDED TO THE ENGINEER OF RECORD (EOR) FOR APPROVAL UPON REQUEST ASSEMBLY • ALL FITTINGS SHALL BE STRUCTURALLY CHECKED FOR REINFORCEMENTS PER ASTM A998 AND PROVIDED TO THE EOR FOR APPROVAL UPON REQUEST SCALE: 1" = 10' • CONNECTING BANDS FOR DETENTION SYSTEMS SHALL BE HUGGER TYPE OR FULLY PIPE STORAGE: 4,776 CF CORRUGATED WITH APPROPRIATE BOLTED CONNECTIONS THAT CAN BE TORQUED TO 35 FOOT LOADI NG: H20 POUNDS. BANDS SHALL MATCH THE SPECIFIED CMP COATING AND MEET THE REQUIREMENTS PIPE INV.= 87.00'± OF AASHTO M 36. • ALL METALLIC COATIN GS AFFECTED BY MANUFACTURING FABRICATION SHALL BE REPAIRED PER AASHTO M 36 SECTION 11 REQUIREMENTS {E.G. ZINC-RICH PAINT ON ALL WELDS). IF POLYMER COATINGS ARE USED THE REPAIR OF DAMAGED COATINGS WILL BE IN CONFORMANCE WITH AASHTO M 245 SECTION 11 REQUIREMENTS. • ACCESS LADDERS SHALL BE ATTACHED BY THE MANUFACTURER PRIOR TO DELIVERY, NOT INSTALLED ON THE JOBSfTE. PROJECT No.: ISEQ. No., I DATE C()NTECH" A s,111,:.a .. rrr-u· 96"0 UNDERGROUND DETENTION SYSTEM -617515-020 617515 020 5118/2021 V~~;,w i I.V!"!! DESIGNED DRAWN ENGINEERED SOLUTIONS LLC CMP DETENTION SYSTEMS BMW CARLSBAD RLH RLH www.ContechES.com CARLSBAD, CA CHECKED APPROVED 11815 NE Glenn Widing Dri.,e. Portland. OR 97220 I PRO~TOC'SAL I SITE DESIGNATION: BMP 6B BY 800-548-4667 HORIZONTAL 6" DIA. SLOTTED PVC UNDERDRAIN co 503-240-3393 800-561-1271 FAX DRAWING NOTES: 1. BMP-6A A ND BMP-6B TO ACT AS ONE DETENTION SYSTEM THAT IS HYDRAULICALY CONNECTED VIA 12" HOPE PIPE A ND SET AT O NE ELEVATION. 5.66' 5.0' SHEET NO P1 Ce 4 I 95 OOTW 2 . BMP-6 SHALL HAVE A MINIMUM TOTA L STORAGE VOLUME OF 10,440 CU-FT. I -1~·'"'1=N~TE=R~N~A~L_T_O_P_ --;-~·1 ______ ==,,,.---~'"i--1~ OF STRUCTURE 94.21 FL METAL PLATE GREATER THAN 6" DIA OPENING 6" PVC PIPE EMBEDDED IN 4" CONCRETE WALL 1.125" DIA. OR IFICE THRU PLATE FLOW CONTROL ORIFICE PLATE 4.0' 0.79' 7.21 ' A t <I. Li <J <J Li L'.l Li 6" PVC PIPE EMBEDDED IN CONCRETE ------~-+---~---------t-~ 0.5' 4.0' 15" DIA. H PE OUTLET PIPE TO PUBLIC SD LINE 0.5' CONCRETE WEIR WALL OR IFICE PLATE t 12" DIA. HOPE INLET PIPE FROM ONSITE DETENTION VAULT (BMP-6B) 12" DIA HOPE INLET PIPE FROM ONS ITE DETENT ION VAULT (BMP-6A) OUTLET STRUCTURE & WEIR DETAIL OVERFLOW WEIR Li <J <J Li ,1 <J <I METAL PLATE ON OUTLET SIDE OF WEIR. SEE DETAIL AB~VE I 87.00INV ~lccNcccTEacRc'cN.ccA-L~B~O=TT=o ~M <J OF STRUCTURE " ,1 ,1 1.125" DIA. OR IFICE · THR U METAL PLATE SHEET 02 OF 02 A t Q_ :, a " en <{ u u a ~ w L a u ,i 2 ml C 0 -a z 0 t,------------------------------------------------------------------1-i' PREPARED FOR: PREPARED BY: AU TONATION INC. 200 SW 1ST STREET, 14TH FLOOR FORT LAUDERDALE, FL 33301 CONTACT CLIFF POWELL TEL (954) 769-6000 Today's Ideas Tomorrow's Reality Commercial Development Resources 4121 Westerly Place #11 2 NevLiport Beach CA 92660 T 949-610-8997 www.CDRwest.com SWQMP ATTACHMENT 2A: HMPEXHIBIT BMW OF CARLSBAD 1060 AUTO CENTER COURT CARLSBAD, CA 92008 I + u O' <{ Q_ en I m CD 0 CD CD 0 " I .._ ____________________________________________________________________________________________________________________ .., _________________________________ .., ______________________ _ ATTACHMENT VI SWMM Input Data in Input Format (Existing & Proposed Models) PRE_DEV [TITLE] [OPTIONS] FLOW_UNITS CFS INFILTRATION GREEN_AMPT FLOW_ROUTING KINWAVE START_DATE 10/01/1951 START_TIME 00:00:00 REPORT_START_DATE 10/01/1951 REPORT_START_TIME 00:00:00 END_DATE 09/30/2008 END_TIME 23:00:00 SWEEP_START 01/01 SWEEP_END 12/31 DRY_DAYS 0 REPORT_STEP 01:00:00 WET_STEP 00:15:00 DRY_STEP 04:00:00 ROUTING_STEP 0:01:00 ALLOW_PONDING NO INERTIAL_DAMPING PARTIAL VARIABLE_STEP 0.75 LENGTHENING_STEP 0 MIN_SURFAREA 0 NORMAL_FLOW_LIMITED BOTH SKIP_STEADY_STATE NO FORCE_MAIN_EQUATION H-W LINK_OFFSETS DEPTH MIN_SLOPE 0 [EVAPORATION] ;;Type Parameters ;;---------- ---------- MONTHLY 0.03 0.05 0.08 0.11 0.13 0.15 0.15 0.13 0.11 0.08 0.04 0.02 DRY_ONLY NO [RAINGAGES] ;; Rain Time Snow Data ;;Name Type Intrvl Catch Source ;;-------------- --------- ------ ------ ---------- Oceanside INTENSITY 1:00 1.0 TIMESERIES Oceanside [SUBCATCHMENTS] ;; Total Pcnt. Pcnt. Curb Snow ;;Name Raingage Outlet Area Imperv Width Slope Length Pack ;;-------------- ---------------- ---------------- -------- -------- -------- -------- -------- -------- DMA-A Oceanside POC-1 3.71 0 979 3 0 [SUBAREAS] ;;Subcatchment N-Imperv N-Perv S-Imperv S-Perv PctZero RouteTo PctRouted ;;-------------- ---------- ---------- ---------- ---------- ---------- ---------- ---------- DMA-A 0.012 0.05 0.05 0.1 25 OUTLET [INFILTRATION] ;;Subcatchment Suction HydCon IMDmax ;;-------------- ---------- ---------- ---------- DMA-A 3 0.15 0.31 [OUTFALLS] ;; Invert Outfall Stage/Table Tide ;;Name Elev. Type Time Series Gate ;;-------------- ---------- ---------- ---------------- ---- POC-1 0 FREE NO [TIMESERIES] ;;Name Date Time Value ;;-------------- ---------- ---------- ---------- Oceanside FILE "OsideRain.prn" [REPORT] INPUT NO PRE_DEV CONTROLS NO SUBCATCHMENTS ALL NODES ALL LINKS ALL [TAGS] [MAP] DIMENSIONS -8510.915 4908.181 -8482.307 8731.478 Units None [COORDINATES] ;;Node X-Coord Y-Coord ;;-------------- ------------------ ------------------ POC-1 -8483.607 5081.967 [VERTICES] ;;Link X-Coord Y-Coord ;;-------------- ------------------ ------------------ [Polygons] ;;Subcatchment X-Coord Y-Coord ;;-------------- ------------------ ------------------ DMA-A -8483.607 6622.951 [SYMBOLS] ;;Gage X-Coord Y-Coord ;;-------------- ------------------ ------------------ Oceanside -8489.868 7908.829 POST_DEV [TITLE] [OPTIONS] FLOW_UNITS CFS INFILTRATION GREEN_AMPT FLOW_ROUTING KINWAVE START_DATE 10/01/1951 START_TIME 00:00:00 REPORT_START_DATE 10/01/1951 REPORT_START_TIME 00:00:00 END_DATE 09/30/2008 END_TIME 23:00:00 SWEEP_START 01/01 SWEEP_END 12/31 DRY_DAYS 0 REPORT_STEP 01:00:00 WET_STEP 00:15:00 DRY_STEP 04:00:00 ROUTING_STEP 0:01:00 ALLOW_PONDING NO INERTIAL_DAMPING PARTIAL VARIABLE_STEP 0.75 LENGTHENING_STEP 0 MIN_SURFAREA 0 NORMAL_FLOW_LIMITED BOTH SKIP_STEADY_STATE NO FORCE_MAIN_EQUATION H-W LINK_OFFSETS DEPTH MIN_SLOPE 0 [EVAPORATION] ;;Type Parameters ;;---------- ---------- MONTHLY 0.03 0.05 0.08 0.11 0.13 0.15 0.15 0.13 0.11 0.08 0.04 0.02 DRY_ONLY NO [RAINGAGES] ;; Rain Time Snow Data ;;Name Type Intrvl Catch Source ;;-------------- --------- ------ ------ ---------- Oceanside INTENSITY 1:00 1.0 TIMESERIES Oceanside [SUBCATCHMENTS] ;;Total Pcnt.Pcnt. Curb Snow ;;Name Raingage Outlet Area Imperv Width Slope Length Pack ;;-------------- ---------------- ---------------- -------- -------- -------- -------- -------- -------- DMA-1D Oceanside BR-3 0.341 96.62 52 1 0 DMA-2A(SM) Oceanside POC-1 0.294 6.73 128 1 0 BR-3 Oceanside Vault 0.01279 0 10 0 0 DMA-1B Oceanside BR-2 0.325 61.22 71 1 0 DMA-1C Oceanside BR-4 0.506 92.52 78 1 0 BR-2 Oceanside Vault 0.00817 0 10 0 0 BR-1 Oceanside Vault 0.01843 0 10 0 0 BR-4 Oceanside Vault 0.009986 0 10 0 0 DMA-1B(Pavers) Oceanside BR-2 0.089 0 77 1 0 DMA-1D(Pavers) Oceanside BR-3 0.053 0 46 1 0 DMA-1E Oceanside VAULT 1.325 100 124 1 0 DMA-1A+Pavers Oceanside BR-1 0.726 61.23 86 1 0 [SUBAREAS] ;;Subcatchment N-Imperv N-Perv S-Imperv S-Perv PctZero RouteTo PctRouted ;;-------------- ---------- ---------- ---------- ---------- ---------- ---------- ---------- DMA-1D 0.012 0.05 0.05 0.1 25 OUTLET DMA-2A(SM) 0.012 0.05 0.05 0.1 25 OUTLET BR-3 0.012 0.05 0.05 0.1 25 OUTLET DMA-1B 0.012 0.05 0.05 0.1 25 OUTLET DMA-1C 0.012 0.05 0.05 0.1 25 OUTLET BR-2 0.012 0.05 0.05 0.1 25 OUTLET BR-1 0.012 0.05 0.05 0.1 25 OUTLET BR-4 0.012 0.05 0.05 0.1 25 OUTLET DMA-1B(Pavers) 0.012 0.05 0.05 2.4 25 PERVIOUS 100 POST_DEV DMA-1D(Pavers) 0.012 0.05 0.05 2.4 25 PERVIOUS 100 DMA-1E 0.012 0.05 0.05 0.1 25 OUTLET DMA-1A+Pavers 0.012 0.05 0.05 2.4 25 PERVIOUS 100 [INFILTRATION] ;;Subcatchment Suction HydCon IMDmax ;;-------------- ---------- ---------- ---------- DMA-1D 3 0.15 0.31 DMA-2A(SM) 3 0.15 0.31 BR-3 3 0.15 0.31 DMA-1B 3 0.15 0.31 DMA-1C 3 0.15 0.31 BR-2 3 0.15 0.31 BR-1 3 0.15 0.31 BR-4 3 0.15 0.31 DMA-1B(Pavers) 3 0.15 0.31 DMA-1D(Pavers) 3 0.15 0.31 DMA-1E 3 0.15 0.31 DMA-1A+Pavers 3 0.15 0.31 [LID_CONTROLS] ;;Type/Layer Parameters ;;-------------- ---------- ---------- BR-1 BC BR-1 SURFACE 7.2 0.00 0.0 0.0 5 BR-1 SOIL 18 0.4 0.2 0.1 5 5 1.5 BR-1 STORAGE 13 0.67 0.041 0 BR-1 DRAIN 0.3175 0.5 4 6 BR-2 BC BR-2 SURFACE 7.2 0.00 0 0 5 BR-2 SOIL 18 0.4 0.2 0.1 5 5 1.5 BR-2 STORAGE 13 0.67 0.041 0 BR-2 DRAIN 0.4261 0.5 4 6 BR-3 BC BR-3 SURFACE 7.2 0.00 0.0 0.0 5 BR-3 SOIL 18 0.4 0.2 0.1 5 5 1.5 BR-3 STORAGE 12 0.67 0 0 BR-3 DRAIN 0.3362 0.5 3 6 BR-4 BC BR-4 SURFACE 7.2 0.00 0.0 0.0 5 BR-4 SOIL 18 0.4 0.2 0.1 5 5 1.5 BR-4 STORAGE 12 0.67 0 0 BR-4 DRAIN 0.4306 0.5 3 6 [LID_USAGE] ;;Subcatchment LID Process Number Area Width InitSatur FromImprv ToPerv Report File ;;-------------- ---------------- ------- ---------- ---------- ---------- ---------- ---------- ----------- BR-3 BR-3 1 557 0 0 100 0 BR-2 BR-2 1 356 0 0 100 0 BR-1 BR-1 1 803 0 0 100 0 BR-4 BR-4 1 435 0 0 100 0 [OUTFALLS] ;;Invert Outfall Stage/Table Tide ;;Name Elev. Type Time Series Gate ;;-------------- ---------- ---------- ---------------- ---- POC-1 0 FREE NO [STORAGE] ;;Invert Max. Init. Storage Curve Ponded Evap. ;;Name Elev. Depth Depth Curve Params Area Frac. Infiltration Parameters ;;-------------- -------- -------- -------- ---------- -------- -------- -------- -------- -------- ----------------- ------ VAULT 0 8 0 TABULAR UBASIN 0 0 [OUTLETS] ;;Inlet Outlet Outflow Outlet Qcoeff/Flap POST_DEV ;;Name Node Node Height Type QTable Qexpon Gate ;;-------------- ---------------- ---------------- ---------- --------------- ---------------- ---------- ---- OUTLET VAULT POC-1 0 TABULAR/HEAD OUTLET NO [CURVES] ;;Name Type X-Value Y-Value ;;-------------- ---------- ---------- ---------- OUTLET Rating 0.000 0.000 OUTLET 0.250 0.015 OUTLET 0.500 0.023 OUTLET 0.750 0.028 OUTLET 1.000 0.033 OUTLET 1.250 0.037 OUTLET 1.500 0.041 OUTLET 1.750 0.044 OUTLET 2.000 0.047 OUTLET 2.250 0.050 OUTLET 2.500 0.053 OUTLET 2.750 0.056 OUTLET 3.000 0.058 OUTLET 3.250 0.060 OUTLET 3.500 0.063 OUTLET 3.750 0.065 OUTLET 4.000 0.067 OUTLET 4.250 0.069 OUTLET 4.500 0.071 OUTLET 4.750 0.073 OUTLET 5.000 0.075 OUTLET 5.250 0.077 OUTLET 5.500 0.079 OUTLET 5.750 0.081 OUTLET 6.000 0.082 OUTLET 6.250 0.084 OUTLET 6.500 0.086 OUTLET 6.750 0.087 OUTLET 7.000 0.089 OUTLET 7.250 0.090 OUTLET 7.500 2.534 OUTLET 7.750 6.273 OUTLET 8.000 11.014 UBASIN Storage 0 1305 UBASIN 8 1305 [TIMESERIES] ;;Name Date Time Value ;;-------------- ---------- ---------- ---------- Oceanside FILE "OsideRain.prn" [REPORT] INPUT NO CONTROLS NO SUBCATCHMENTS ALL NODES ALL LINKS ALL [TAGS] [MAP] DIMENSIONS -11502.645 3423.967 -5798.942 8802.155 Units None [COORDINATES] ;;Node X-Coord Y-Coord ;;-------------- ------------------ ------------------ POC-1 -8925.024 4095.217 VAULT -8933.210 5413.160 [VERTICES] ;;Link X-Coord Y-Coord ;;-------------- ------------------ ------------------ POST_DEV [Polygons] ;;Subcatchment X-Coord Y-Coord ;;-------------- ------------------ ------------------ DMA-1D -8483.607 7590.164 DMA-2A(SM) -6058.201 4832.451 BR-3 -8500.000 6590.164 DMA-1B -10169.293 7631.560 DMA-1C -6798.942 7548.501 BR-2 -9761.905 6613.757 BR-1 -11225.284 6616.499 BR-4 -6781.305 6684.303 DMA-1B(Pavers) -9547.158 7631.560 DMA-1D(Pavers) -7877.219 7598.816 DMA-1E -6780.297 5707.855 DMA-1A+Pavers -11217.098 7656.118 [SYMBOLS] ;;Gage X-Coord Y-Coord ;;-------------- ------------------ ------------------ Oceanside -8509.615 8557.692 ATTACHMENT VII EPA SWMM FIGURES AND EXPLANATIONS Per the attached, the reader can see the screens associated with the EPA‐SWMM Model in both pre‐development and post‐development conditions. Each portion, i.e., sub‐catchments, outfalls, storage units, weir as a discharge, and outfalls (point of compliance), are also shown. Variables for modeling are associated with typical recommended values by the EPA‐SWMM model, typical values found in technical literature (such as Maidment’s Handbook of Hydrology). Recommended values for the SWMM model have been attained from Appendix G of the 2016 City of Carlsbad BMP Design Manual. Soil characteristics of the existing soils were determined from the site specific geotechnical investigation (located in Attachment VIII of this report). A Technical document prepared by Tory R Walker Engineering for the Cities of San Marcos, Oceanside and Vista (Reference [1]) can also be consulted for additional information regarding typical values for SWMM parameters. Manning’s roughness coefficients have been based upon the findings of the “Improving Accuracy in Continuous Hydrologic Modeling: Guidance for Selecting Pervious Overland Flow Manning’s n Values in the San Diego Region” date 2016 by TRW Engineering (Reference [6]). PRE‐DEVELOPED CONDITIONS G) SWMM S -PRE-DEV.inp -[Study Area Map] @ File Edit View Project Report T cols Window Help Data Map ..... Title/Notes i .. Options i .. Climatology iiJ .. Hydrology &) .. Hydraulics iiJ .. Quality $··Curves L.. Time Series ! .... Time Patterns L .. Map Labels + -~ •• ~! Title/Notes C? @ e © T - Oceanside 121 OMA-A ' POC-1 • Auto-Length: Off • I Offsets: Depth • I Flow Units: CFS • lill Zoom Level: 100% I X,Y: ·9067.404, 8731.478 Outfall POC-1 I Property Name X-Coordinate Y-Coordinate Description Tag Inflows Treatment Invert EL Tide Gate Type Fixed Stage Curve Name - - I Series Name I value POC-1 2500,000 2700 .. 000 NO NO 0 NO FREE 0 ~ Rain Gage Oceanside ! Property Name X-Coordinate -8509.615 Y-Coordinate 8557 .. 692 Description Tag Rain Format Time Interval Snow Catch Factor Data Source -File Name -Station ID -Rain Units INTENSITY 1 :00 10 TIME SERIES IN User-assigned name of rain gage □ X -e X Subcatchment DMA-A Property Value Name \DMA-A X-Coordinate -8483.607 Y-Coordinate 6622.951 Description Tag Rain Gage Oceanside Outlet POC-1 Area 3.71 Width 979 % Slope 3 %1mperv 0 N-lmperv 0.012 N-Perv 0.05 Dstore-lmperv 0.05 Dstore-Perv 0.1 %Zero-lmperv 25 Subarea Routing OUTLET Percent Routed 100 Infiltration GREEN_AMPT Groundwater NO Snow Pack LID Controls 0 Land Uses 0 Initial Buildup NONE Curb Length 0 User-assigned name of subcatchment Infiltration Editor Infiltration Method Property Suction Head ,- Conductivity f--lnitial Deficit f- GREEN_AMPT !Value 0.15 0.31 a X POST‐DEVELOPED CONDITIONS (i; SWMM S -POST-DEV-BASIN.inp ____ GJ[§J~ File Edit View Project Report Tools Window Help Data I Map I · · Title/Notes ·.·Options :···· Climatolog_y I~ H_ydrology !···· Rain Gages 1•---Subcatchments ! ... Aquifers ; Snow Packs I·· Unit Hydrographs L LID Controls [~--Hydraulics (~l-Nodes ·. · Junctions ··· Outfalls · Dividers l : .. U~k:torage Units I•••••.···· Con.duits , .... Pumps !···· Orifices 1-•··Weirs : .... Outlets , ... Transects + -~ i} 0 u Subcatchments DMA-1D DMA-2A[SMJ BR-3 DMA-1B DMA-lC BR-2 BR-1 BR-4 DMA-1 B[Pavers) DMA-1D(Pavers) 11]§@0 DMA-1A+Pavers ;\?;, Study Area Map DMA-1A+Pave ' BR-1 • Oceanside 5rl DMA-1B .. OMA-1 B(Paver DMA-10 DMA-1D(Pavers) DMA-lC ' ' \iR-2 .. ~~,r ' )I BR-3 • :,09----- DMA-1E ------ g[§J~ IHOIIIIM■IIIHl■IOE. DMA-2A(SM) ----- Auto-Length: Off ... 1 Offsets: Depth ... 1 Flow Units: CFS ... 1 i11 Zoom Level: 100% I X,Y: -7601.179, 8151.568 Outfall POC-1 Property Name X-Coordinate Y-Coordinate Description Tag Inflows Treatment Invert Et Tide Gate Type Value I~?.-~.:~----····-.... --------·-·-·-·· -290.792 4991.922 NO NO 0 NO FREE User-assigned name of outfall Rain Gage Oceanside Property Value Name X-Coordinate Y-Coordinate Description Tag Rain Format Time Interval Snow Catch Factor Data Source · Series Name -File Name · Station ID -Rain Units !Name of rainfall data file Oceanside -8509.615 8557.692 INTENSITY 1:00 1.0 TIMESERIES Oceanside :,::::::::::::::::::::::::::::::::::::: ... 3 IN II. Subcatchment DMA-lA+Pavers ~ Subcatchment BR-1 a Property !Value Name \DMA-1A+Pavers Property Value Name BR-1 ~ X-Coordinate -11217.098 X-Coordinate ·11225.284 ~ Y-Coordinate 7656.118 Y-Coordinate 6616.499 ~ Description -Description Tag -Tag Rain Gage Oceanside Rain Gage Oceanside Dutlet 8R-1 Dutlet Vault ~ Area 0.726 Area 0.01843 c--Width 86 Width 10 c-% Slope 1 ~ % Slope 0 %1mperv 61.23 ~ %1mperv 0 N-lmperv 0.012 -N-lmperv 0.012 N-Perv 0.05 N-Perv 0.05 -Dstore·lmperv 0.05 ~ Dstore-lmperv 0.05 Dstore-Perv 2.4 Dstore-Perv 0.1 ~ %Zero-lmperv 25 ~ %Zero-lmperv 25 Subarea Routing PERVIDUS ~ Subarea Routing DUTLET Percent Routed 100 Percent Routed 100 ~ GREEN_AMPT Infiltration Groundwater ND Infiltration \GREEN_AMPT ---I Groundwater ND -Snow Pack Snow Pack ~ LID Controls 0 LID Controls 1 c-Land Uses 0 Land Uses 0 ~ Initial Buildup NDNE ~ Initial Buildup NDNE Curb Length 0 ~ Curb Length 0 User-assigned name of subcatchment Infiltration parameters (click to edit) - Infiltration Editor X Infiltration Editor X Infiltration Method GREEN_AMPT Infiltration Method GREEN_AMPT Property !Value Property !Value Suction Head \3 Suction Head \3 Conductivity 0.15 Conductivity 0.15 ,- 0.31 c--0.31 Initial Deficit Initial Deficit c-c- Subcatchment DMA-lB ~ Subcatchment DMA-lB(Pavers) ~ Property Value I Property Value Name DMA-1B Name jDMA-1B(Pavers) -X-Coordinate -10169.293 X-Coordinate -9547.158 -Y-Coordinate 7631.560 Y-Coordinate 7631.560 -Description Description -Tag Tag -Rain Gage Oceanside Rain Gage Oceanside Dutlet BR-2 Dutlet BR-2 -Area 0.325 Area 0.089 -Width 71 Width 77 -% Slope 1 % Slope -%1mperv 61.22 %1mperv 0 -N-lmperv 0.012 N-lmperv 0.012 -N-Perv 0.05 N-Perv 0.05 -Dstore·lmperv 0.05 Dstore-lmperv 0.05 -Dstore-Perv 0.1 Dstore-Perv 2.4 -%Zero-lmperv 25 %Zero·lmperv 25 -Subarea Routing DUTLET Subarea Routing PERVIDUS -Percent Routed 100 Percent Routed 100 -Infiltration GREEN_AMPT Infiltration GREEN_AMPT Groundwater ND Groundwater ND -Snow Pack Snow Pack -LID Controls 0 LID Controls 0 -Land Uses 0 Land Uses 0 -Initial Buildup NDNE Initial Buildup NDNE -Curb Length 0 Curb Length 0 - User-assigned name of subcatchment User-assigned name of subcatchment - Infiltration Editor X Infiltration Editor X Infiltration Method GREEN_AMPT Infiltration Method GREEN_AMPT Property !Value Property !Value Suction Head \3 Suction Head \3 -f-Conductivity 0.15 Conductivity 0.15 -f--Initial Deficit 0.31 Initial Deficit 0.31 -f- Subcatchment BR-2 ~ Subcatchment DMA-lD(Pavers) ~ Property Value I Property Value Name BR-2 Name jDMA-lD(Pavers) -X-Coordinate -9761.905 X-Coordinate -7877.219 -Y-Coordinate 6613.757 Y-Coordinate 7598.816 -Description Description -Tag Tag -Rain Gage Oceanside Rain Gage Oceanside Outlet Vault Outlet BR-3 -Area 0.00817 Area 0.053 -Width 10 Width 46 -% Slope 0 % Slope -%1mperv 0 %1mperv 0 -N-lmperv 0.012 N-lmperv 0.012 -N-Perv 0.05 N-Perv 0.05 -Dstore·lmperv 0.05 Dstore-lmperv 0.05 -Dstore-Perv 0.1 Dstore-Perv 2.4 -%Zero-lmperv 25 %Zero·lmperv 25 -Subarea Routing OUTLET Subarea Routing PERVIOUS -Percent Routed 100 Percent Routed 100 -Infiltration GREEN_AMPT Infiltration GREEN_AMPT Groundwater NO Groundwater NO -Snow Pack Snow Pack -LID Controls 1 LID Controls 0 -Land Uses 0 Land Uses 0 -Initial Buildup NONE Initial Buildup NONE -Curb Length 0 Curb Length 0 - User-assigned name of subcatchment User-assigned name of subcatchment - Infiltration Editor X Infiltration Editor X Infiltration Method GREEN_AMPT Infiltration Method GREEN_AMPT Property !Value Property !Value Suction Head \3 Suction Head \3 -f-Conductivity 0.15 Conductivity 0.15 -f--Initial Deficit 0.31 Initial Deficit 0.31 -f- Subcatchment DMA-lD ~ Subcatchment 8R-3 ~ Property Value I Property Value Name DMA-1D Name SR-~ ----X-Coordinate -8483.607 X-Coordinate -8500.000 --Y-Coordinate 7590.164 Y-Coordinate 6590.164 --Description Description --Tag Tag --Rain Gage Oceanside Rain Gage Oceanside ~ Dutlet 8R-3 Dutlet Vault --Area 0.341 Area 0.01279 --Width 52 Width 10 --% Slope 1 % Slope 0 --%1mperv 96.62 %1mperv 0 --N-lmperv 0.012 N-lmperv 0.012 --N-Perv 0.05 N-Perv 0.05 --Dstore·lmperv 0.05 Dstore-lmperv 0.05 --Dstore-Perv 0.1 Dstore-Perv 0.1 --%Zero-lmperv 25 %Zero·lmperv 25 -~ Subarea Routing DUTLET Subarea Routing DUTLET --Percent Routed 100 Percent Routed 100 --Infiltration GREEN_AMPT Infiltration GREEN_AMPT Groundwater ND Groundwater ND --Snow Pack Snow Pack --LID Controls 0 LID Controls 1 --Land Uses 0 Land Uses 0 --Initial Buildup NDNE Initial Buildup NDNE --Curb Length 0 Curb Length 0 --User-assigned name of subcatchment User-assigned name of subcatchment - Infiltration Editor X Infiltration Editor X Infiltration Method GREEN_AMPT Infiltration Method GREEN_AMPT Property !Value Property !Value Suction Head \3 Suction Head \3 --Conductivity 0.15 Conductivity 0.15 --Initial Deficit 0.31 Initial Deficit 0.31 -f- Subcatchment DMA-lC ~ Subcatchment 8R-4 ~ Property Value Property Value Name DMA-1Q Name SR-~ ------X-Coordinate -6798.942 X-Coordinate -6781.305 --Y-Coordinate 7548.501 Y-Coordinate 6684.303 --Description Description --Tag Tag --Rain Gage Oceanside Rain Gage Oceanside ~ Dutlet 8R-4 Dutlet Vault --Area 0.506 Area 0.009986 --Width 78 Width 10 --% Slope 1 % Slope 0 --%1mperv 92.52 %1mperv 0 --N-lmperv 0.012 N-lmperv 0.012 --N-Perv 0.05 N-Perv 0.05 --Dstore·lmperv 0.05 Dstore-lmperv 0.05 --Dstore-Perv 0.1 Dstore-Perv 0.1 --%Zero-lmperv 25 %Zero·lmperv 25 -~ Subarea Routing DUTLET Subarea Routing DUTLET --Percent Routed 100 Percent Routed 100 --Infiltration GREEN_AMPT Infiltration GREEN_AMPT Groundwater ND Groundwater ND --Snow Pack Snow Pack --LID Controls 0 LID Controls 1 --Land Uses 0 Land Uses 0 --Initial Buildup NDNE Initial Buildup NDNE --Curb Length 0 Curb Length 0 --User-assigned name of subcatchment User-assigned name of subcatchment - Infiltration Editor X Infiltration Editor X Infiltration Method GREEN_AMPT Infiltration Method GREEN_AMPT Property !Value Property !Value Suction Head \3 Suction Head \3 --Conductivity 0.15 Conductivity 0.15 --Initial Deficit 0.31 Initial Deficit 0.31 -f- Subcatchment DMA-lE ~ Subcatchment DMA-2A(SM) ~ Property Value I Property Value Name DMA-1E Name jDMA-2A(SM) -X-Coordinate -6780.297 X-Coordinate -6058.201 -Y-Coordinate 5707.855 Y-Coordinate 4832.451 -Description Description -Tag Tag -Rain Gage Oceanside Rain Gage Oceanside Dutlet VAULT Dutlet PDC-1 -Area 1.325 Area 0.294 -Width 124 Width 128 -% Slope 1 % Slope -%1mperv 100 %1mperv 6.73 -N-lmperv 0.012 N-lmperv 0.012 -N-Perv 0.05 N-Perv 0.05 -Dstore·lmperv 0.05 Dstore-lmperv 0.05 -Dstore-Perv 0.1 Dstore-Perv 0.1 -%Zero-lmperv 25 %Zero·lmperv 25 -Subarea Routing DUTLET Subarea Routing DUTLET -Percent Routed 100 Percent Routed 100 -Infiltration GREEN_AMPT Infiltration GREEN_AMPT Groundwater ND Groundwater ND -Snow Pack Snow Pack -LID Controls 0 LID Controls 0 -Land Uses 0 Land Uses 0 -Initial Buildup NDNE Initial Buildup NDNE -Curb Length 0 Curb Length 0 - User-assigned name of subcatchment User-assigned name of subcatchment - Infiltration Editor X Infiltration Editor X Infiltration Method GREEN_AMPT Infiltration Method GREEN_AMPT Property !Value Property !Value Suction Head \3 Suction Head \3 -f-Conductivity 0.15 Conductivity 0.15 -f--Initial Deficit 0.31 Initial Deficit 0.31 -f- Detention Vault Storage Unit VAULT Property Name X-Coordinate Y-Coordinate Description Tag Inflows Treatment Invert El. Max. Depth Initial Depth Ponded Area Evap. Factor Infiltration Storage Curve Functional Cu1ve Coefficient Exponent Constant Value VAULT -8933.210 5413.160 ND ND 0 8 0 0 0 ND TABULAR 1000 0 0 U8ASIN a Outlet OUTLET a Property Value Name \DUTLET ·------------' Inlet Node VAULT Dutlet Node PDC-1 Description Tag Inlet Dffset Flap Gate Rating Curve Functional Cu1ve Coefficient Exponent 0 ND T A8ULAR/HEAD 10.0 0.5 User-assigned name of outlet Storage Curve Editor Curve Name @=H-1141 Description Depth (ft) 0 2 8 3 4 5 6 7 8 9 Rating Curve Editor Curve Name @-111:11 Description Head (ft) 0.000 2 0.250 3 0.500 4 0.750 5 1.000 6 1.250 7 1.500 8 1.750 9 2.000 I ra,.1 ~ ~ Area A ~iew ... I (ft2) D 1305 Load ... 1305 ~ave ... DK Cancel T !ielp I ra,.1 ~ ~ Dutflow A ~iew ... I (CFS) D 0.000 Load ... 0.015 0.023 ~ave ... 0.028 0.033 DK 0.037 0.041 Cancel 0.044 0.047 T !ielp EXPLANATION OF SELECTED VARIABLES Sub Catchment Areas: Please refer to the attached diagrams that indicate the DMA and Bio‐Retention BMPs (BMP) sub areas modeled within the project site at both the pre and post developed conditions draining to the POC. Parameters for the pre‐ and post‐developed models include soil type B as determined from the site specific geotechnical investigation (attached at the end of this appendix). Suction head, conductivity and initial deficit corresponds to average values expected for these soils types, according to Appendix G of the 2016 City of Carlsbad BMP Design Manual. For surface runoff infiltration values, REC selected infiltration values per Appendix G of the 2016 City of Carlsbad BMP Design Manual corresponding to hydrologic soil type. Selection of a Kinematic Approach: As the continuous model is based on hourly rainfall, and the time of concentration for the pre‐development and post‐development conditions is significantly smaller than 60 minutes, precise routing of the flows through the impervious surfaces, the underdrain pipe system, and the discharge pipe was considered unnecessary. The truncation error of the precipitation into hourly steps is much more significant than the precise routing in a system where the time of concentration is much smaller than 1 hour. Sub‐catchment BMP: The area of biofiltration must be equal to the area of the development tributary to the biofiltration facility (area that drains into the biofiltration, equal external area plus bio‐retention itself). Five (5) decimal places were given regarding the areas of the biofiltration to insure that the area used by the program for the LID subroutine corresponds exactly with this tributary. LID Usage Editor X LID Usage Editor X Control Name 1rnm vi Control Name lllllE vi Number of Replicate Units I 1 IF-l Number of Replicate Units I 1 I~ Area of Each Unit (sq ft or sq m) 1003 Area of Each Unit (sq ft or sq m) 1356 % of Subcatchment Occupied 100.0 % of Subcatchment Occupied 100.0 Top Width of Overland Flow 10 Top Width of Overland Flow 10 Surface of Each Unit (ft or m) Surface of Each Unit (ft or m) % Initially Saturated 10 % Initially Saturated 10 % of Impervious Area Treated 1100 % of Impervious Area Treated 1100 LID Usage Editor X LID Usage Editor X Control Name l[DJ vi Control Name ltD vi Number of Replicate Units I 1 IF-l Number of Replicate Units I 1 IF-l Area of Each Unit (sq ft or sq m) 1557 Area of Each Unit (sq ft or sq m) 1435 % of Subcatchment Occupied 100.0 % of Subcatchment Occupied 100.0 Top Width of Overland Flow 10 Top Width of Overland Flow 10 Surface of Each Unit (ft or m) Surface of Each Unit (ft or m) % Initially Saturated 10 % Initially Saturated 10 % of Impervious Area Treated 1100 % of Impervious Area Treated 1100 LID Control Editor Control Name: IIUI LID Type: I Bio-Retention Cell Process Layers: Surf ace Soil Storage Underdrain Storage Depth 172 (in. ormm) Vegetation Volume 1000 Fraction Surf ace Roughness 100 (Mannings n) Surf ace Slope 100 (percent) LID Control Editor Control Name: IIUI LID Type: I Bio-Retention Cell Process Layers: Surface Soil Storage Underdrain Height 113 (in. or mm) ~-----' Void Ratio I 0.67 [Voids I Solids) '-------' Conductivity (in/hr or mm/hr) Clogging Factor 10041 10 Note: use a Conductivity of O if the LID unit has an impermeable bottom. ~-□-K_~I I Cancel I ~I _H_el_P ~ X X LID Control Editor Control Name: LID Type: I Bio-Retention Cell Process Layers: Surface Soil Storage Underdrain Thickness 11a (in. ormm) Porosity 104 (volume fraction) Field Capacity 102 (volume fraction) Wilting Point 101 (volume fraction) Conductivity 15 (in/hr or mm/hr) Conductivity Slope 15 Suction Head 115 (in. ormm) OK Help LID Control Editor Control Name: IIUI LID Type: I Bio-Retention Cell Process Layers: Surface Soil Storage Underdrain Drain Coefficient I 0.3175 (in/hr or mm/hr) ~-----' Drain Exponent .... I 0_.5 ____ _, Drain Offset Height (in. ormm) Note: use a Drain Coefficient of O if the LID unit has no underdrain. ~-O_K_~I I Cancel I ~I _H_el_P ~ X X LID Control Editor X Control Name: lllllE LID Type: I Bio-Retention Cell Process Layers: Surface Soil Storage Underdrain Storage Depth 172 (in. ormm) Vegetation Volume 1000 Fraction Surf ace Roughness 10 (Mannings n) Surf ace Slope 10 (percent) LID Control Editor X Control Name: ~11=_);_1!_~ ________ ~ LID Type: I Bio-Retention Cell Process Layers: Surface Soil Storage Underdrain Height 113 (in. or mm) ~-----' Void Ratio I 0.67 [Voids I Solids) '-------' Conductivity (in/hr or mm/hr) Clogging Factor 10041 10 Note: use a Conductivity of O if the LID unit has an impermeable bottom. LID Control Editor X Control Name: LID Type: I Bio-Retention Cell Process Layers: Surface Soil Storage Underdrain Thickness 11a (in. ormm) Porosity 104 (volume fraction) Field Capacity 102 (volume fraction) Wilting Point 101 (volume fraction) Conductivity 15 (in/hr or mm/hr) Conductivity Slope 15 Suction Head 115 (in. ormm) LID Control Editor X Control Name: ~11=_);_1!_~ ________ __, LID Type: I Bio-Retention Cell Process Layers: Surface Soil Storage Underdrain Drain Coefficient I0.4261 (in/hr or mm/hr) ~-----' Drain Exponent ~I 0_.5 ____ _, Drain Offset Height (in. ormm) Note: use a Drain Coefficient of O if the LID unit has no underdrain. OK Help LID Control Editor X Control Name: IID LID Type: I Bio-Retention Cell Process Layers: Surface Soil Storage Underdrain Storage Depth 172 (in. ormm) Vegetation Volume 1000 Fraction Surf ace Roughness 100 (Mannings n) Surf ace Slope 100 (percent) LID Control Editor X Control Name: ~ll=_li_l_l ________ ~ LID Type: I Bio-Retention Cell Process Layers: Surface Soil Storage Underdrain Height 112 (in. or mm) ~-----' Void Ratio I 0.67 [Voids I Solids) '-------' Conductivity (in/hr or mm/hr) Clogging Factor 10 10 Note: use a Conductivity of O if the LID unit has an impermeable bottom. Cancel LID Control Editor X Control Name: LID Type: I Bio-Retention Cell Process Layers: Surface Soil Storage Underdrain Thickness 1,a (in. ormm) Porosity 104 (volume fraction) Field Capacity 102 (volume fraction) Wilting Point 10, (volume fraction) Conductivity 15 (in/hr or mm/hr) Conductivity Slope 15 Suction Head 1, 5 (in. ormm) LID Control Editor X Control Name: ~ll=_li_l_l ________ __, LID Type: I Bio-Retention Cell Process Layers: Surface Soil Storage Underdrain Drain Coefficient I 0.3362 (in/hr or mm/hr) ~-----' Drain Exponent ~I 0_.5 ____ _, Drain Offset Height (in. ormm) Note: use a Drain Coefficient of O if the LID unit has no underdrain . .___□_K_~I I Cancel ` LID Control Editor X Control Name: LID Type: I Bio-Retention Cell Process Layers: Surface Soil Storage Underdrain Storage Depth 172 (in. ormm) Vegetation Volume 1000 Fraction Surf ace Roughness 100 (Mannings n) Surf ace Slope 100 (percent) LID Control Editor X Control Name: ..._IIDJ_· ________ __, LID Type: I Bio-Retention Cell Process Layers: Surface Soil Storage Underdrain Height 112 (in. or mm) '-------' Void Ratio I 0.67 (Voids/ Solids) '--------' Conductivity (in/hr or mm/hr) Clogging Factor 10 10 Note: use a Conductivity of O if the LID unit has an impermeable bottom. OK LID Control Editor X Control Name: LID Type: I Bio-Retention Cell Process Layers: Surface Soil Storage Underdrain Thickness 1,a (in. ormm) Porosity 104 (volume fraction) Field Capacity 102 (volume fraction) Wilting Point 10, (volume fraction) Conductivity 15 (in/hr or mm/hr) Conductivity Slope 15 Suction Head 1, 5 (in. ormm) LID Control Editor X Control Name: ..._IIDJ_· ________ __, LID Type: I Bio-Retention Cell Process Layers: Surface Soil Storage Underdrain Drain Coefficient I0.4306 (in/hr or mm/hr) '-------' Drain Exponent ..._I 0_.5 ____ _, Drain Offset Height (in. ormm) Note: use a Drain Coefficient of O if the LID unit has no underdrain . ...___□_K_...,I I Cancel LID Control Editor: Explanation of Significant Variables Storage Depth: The storage depth variable within the SWMM model is representative of the storage volume provided beneath the surface riser outlet and the surface of the bio filtration facility. In those cases where the surface storage has a variable area that is also different to the area of the gravel and amended soil, the SWMM model needs to be calibrated as the LID module will use the storage depth multiplied by the BMP area as the amount of volume stored at the surface. Let ABMP be the area of the BMP (area of amended soil and area of gravel). The proper value of the storage depth SD to be included in the LID module can be calculated by using geometric properties of the surface volume. Let A0 be the surface area at the bottom of the surface pond, and let Ai be the surface area at the elevation of the invert of the first row of orifices (or at the invert of the riser if not surface orifices are included). Finally, let hi be the difference in elevation between A0 and Ai. By volumetric definition: ܣெ ܵ ൌ ሺబାሻ ଶ ݄ (1) Equation (1) allows the determination of SD to be included as Storage Depth in the LID module. The 3‐inches of gravel volume (3‐inches x volume of solids (0.6) = 1.8‐inches) is then subtracted from this volume. Porosity: A porosity value of 0.4 has been selected for the model. The amended soil is to be highly sandy in content in order to have a saturated hydraulic conductivity of approximately 5 in/hr. REC considers such a value to be slightly high; however, in order to comply with the HMP Permit, the value recommended by the Copermittees for the porosity of amended soil is 0.4, per Appendix A of the Final Hydromodification Management Plan by Brown & Caldwell, dated March 2011. Such porosity is equal to the porosity of the gravel per the same document. Void Ratio: The ratio of the void volume divided by the soil volume is directly related to porosity as n/(1‐n). As the underdrain layer is composed of gravel, a porosity value of 0.4 has been selected (also per Appendix A of the Final HMP document), which results in a void ratio of 0.4/(1‐0.4) = 0.67 for the gravel detention layer. Conductivity: Per the site‐specific geotechnical investigation for the project site infiltration is only feasible for basins to the east of the project site, a factored infiltration rate of 0.041 in/hr has been used for these facilities. For the western basins, a value of 0 has been assigned for conductivity accordingly. Clogging factor: A clogging factor was not used (0 indicates that there is no clogging assumed within the model). The reason for this is related to the fairness of a comparison with the SDHM model and the HMP sizing tables: a clogging factor was not considered, and instead, a conservative value of infiltration was recommended. Drain (Flow) coefficient: The flow coefficient C in the SWMM Model is the coefficient needed to transform the orifice equation into a general power law equation of the form: ݍൌܥሺܪെܪሻ (2) where q is the peak flow in in/hr, n is the exponent (typically 0.5 for orifice equation), HD is the elevation of the centroid of the orifice in inches (assumed equal to the invert of the orifice for small orifices and in our design equal to 0) and H is the depth of the water in inches. The general orifice equation can be expressed as: ܳൌగ ସ ܿ మ ଵସସ ට2݃ ሺுିுವሻ ଵଶ (3) where Q is the peak flow in cfs, D is the diameter in inches, cg is the typical discharge coefficient for orifices (0.61‐0.63 for thin walls and around 0.75‐0.8 for thick walls), g is the acceleration of gravity in ft/s2, and H and HD are defined above and are also used in inches in Equation (3). It is clear that: ݍ ቀ ቁܺ ಳಾು ଵଶ ଷ ൌ ܳ ሺ݂ܿݏሻ (4) Cut‐Off Flow: Q (cfs) and q (in/hr) are also the cutoff flow. For numerical reasons to insure the LID is full, the model uses cut‐off = 1.01 Q. Overland Flow Manning’s Coefficient per TRWE (Reference [6]) 3 Further discussion is provided on page 6 under “Discussion of Differences Between Manning’s n Values” 3 appeal of a de facto value, we anticipate that jurisdictions will not be inclined to approve land surfaces other than short prairie grass. Therefore, in order to provide SWMM users with a wider range of land surfaces suitable for local application and to provide Copermittees with confidence in the design parameters, we recommend using the values published by Yen and Chow in Table 3-5 of the EPA SWMM Reference Manual Volume I – Hydrology. SWMM-Endorsed Values Will Improve Model Quality In January 2016, the EPA released the SWMM Reference Manual Volume I – Hydrology (SWMM Hydrology Reference Manual). The SWMM Hydrology Reference Manual complements the SWMM 5 User’s Manual and SWMM 5 Applications Manual by providing an in-depth description of the program’s hydrologic components (EPA 2016). Table 3-5 of the SWMM Hydrology Reference Manual expounds upon SWMM 5 User’s Manual Table A.6 by providing Manning’s n values for additional overland flow surfaces3. The values are provided in Table 1: Table 1: Manning’s n Values for Overland Flow (EPA, 2016; Yen 2001; Yen and Chow, 1983). Overland Surface Light Rain (< 0.8 in/hr) Moderate Rain (0.8-1.2 in/hr) Heavy Rain (> 1.2 in/hr) Smooth asphalt pavement 0.010 0.012 0.015 Smooth impervious surface 0.011 0.013 0.015 Tar and sand pavement 0.012 0.014 0.016 Concrete pavement 0.014 0.017 0.020 Rough impervious surface 0.015 0.019 0.023 Smooth bare packed soil 0.017 0.021 0.025 Moderate bare packed soil 0.025 0.030 0.035 Rough bare packed soil 0.032 0.038 0.045 Gravel soil 0.025 0.032 0.045 Mowed poor grass 0.030 0.038 0.045 Average grass, closely clipped sod 0.040 0.050 0.060 Pasture 0.040 0.055 0.070 Timberland 0.060 0.090 0.120 Dense grass 0.060 0.090 0.120 Shrubs and bushes 0.080 0.120 0.180 Land Use Business 0.014 0.022 0.035 Semibusiness 0.022 0.035 0.050 Industrial 0.020 0.035 0.050 Dense residential 0.025 0.040 0.060 Suburban residential 0.030 0.055 0.080 Parks and lawns 0.040 0.075 0.120 For purposes of local hydromodification management BMP design, these Manning’s n values are an improvement upon the values presented by Engman (1986) in SWMM 5 User’s Manual Table A.6. Values from SWMM 5 User’s Manual Table A.6, while completely suitable for the intended application to certain agricultural land covers, comes with the disclaimer that the provided Manning’s n values are valid for shallow-depth overland flow that match the conditions in the experimental plots (Engman, ATTACHMENT VIII Geotechnical Documentation Hydrologic Soil Group—San Diego County Area, California Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 7/19/2019 Page 1 of 4366618036662003666220366624036662603666280366630036663203666340366618036662003666220366624036662603666280366630036663203666340469660469680469700469720469740469760469780469800469820469840469860469880469900 469660 469680 469700 469720 469740 469760 469780 469800 469820 469840 469860 469880 469900 33° 8' 7'' N 117° 19' 31'' W33° 8' 7'' N117° 19' 21'' W33° 8' 2'' N 117° 19' 31'' W33° 8' 2'' N 117° 19' 21'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 11N WGS84 0 50 100 200 300Feet 0 15 30 60 90Meters Map Scale: 1:1,200 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. USDA = MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Rating Polygons A A/D B B/D C C/D D Not rated or not available Soil Rating Lines A A/D B B/D C C/D D Not rated or not available Soil Rating Points A A/D B B/D C C/D D Not rated or not available 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: San Diego County Area, California Survey Area Data: Version 13, Sep 12, 2018 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Nov 3, 2014—Nov 22, 2014 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. Hydrologic Soil Group—San Diego County Area, California Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 7/19/2019 Page 2 of 4USDA = □ D D D D D D D D ,,..,,,. ,,..,,,. □ ■ ■ □ □ ,,..._., t-+-t ~ tllWI ,..,,. ~ • Hydrologic Soil Group Map unit symbol Map unit name Rating Acres in AOI Percent of AOI CbB Carlsbad gravelly loamy sand, 2 to 5 percent slopes B 1.5 39.4% MlC Marina loamy coarse sand, 2 to 9 percent slopes B 2.3 60.6% Totals for Area of Interest 3.8 100.0% Description Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms. The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (A/D, B/D, and C/D). The groups are defined as follows: Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential) when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes. Hydrologic Soil Group—San Diego County Area, California Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 7/19/2019 Page 3 of 4USDA = Rating Options Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher Hydrologic Soil Group—San Diego County Area, California Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 7/19/2019 Page 4 of 4~ ATTACHMENT IX Summary Files from the SWMM Model PRE_DEV EPA STORM WATER MANAGEMENT MODEL - VERSION 5.0 (Build 5.0.022) -------------------------------------------------------------- ********************************************************* NOTE: The summary statistics displayed in this report are based on results found at every computational time step, not just on results from each reporting time step. ********************************************************* **************** Analysis Options **************** Flow Units ............... CFS Process Models: Rainfall/Runoff ........ YES Snowmelt ............... NO Groundwater ............ NO Flow Routing ........... NO Water Quality .......... NO Infiltration Method ...... GREEN_AMPT Starting Date ............ OCT-01-1951 00:00:00 Ending Date .............. SEP-30-2008 23:00:00 Antecedent Dry Days ...... 0.0 Report Time Step ......... 01:00:00 Wet Time Step ............ 00:15:00 Dry Time Step ............ 04:00:00 ************************** Volume Depth Runoff Quantity Continuity acre-feet inches ************************** --------- ------- Total Precipitation ...... 208.490 674.360 Evaporation Loss ......... 0.768 2.485 Infiltration Loss ........ 197.677 639.388 Surface Runoff ........... 10.899 35.251 Final Surface Storage .... 0.000 0.000 Continuity Error (%) ..... -0.410 ************************** Volume Volume Flow Routing Continuity acre-feet 10^6 gal ************************** --------- --------- Dry Weather Inflow ....... 0.000 0.000 Wet Weather Inflow ....... 10.899 3.551 Groundwater Inflow ....... 0.000 0.000 RDII Inflow .............. 0.000 0.000 External Inflow .......... 0.000 0.000 External Outflow ......... 10.899 3.551 Internal Outflow ......... 0.000 0.000 Storage Losses ........... 0.000 0.000 Initial Stored Volume .... 0.000 0.000 Final Stored Volume ...... 0.000 0.000 Continuity Error (%) ..... 0.000 *************************** Subcatchment Runoff Summary *************************** -------------------------------------------------------------------------------------------------------- Total Total Total Total Total Total Peak Runoff Precip Runon Evap Infil Runoff Runoff Runoff Coeff Subcatchment in in in in in 10^6 gal CFS -------------------------------------------------------------------------------------------------------- DMA-A 674.36 0.00 2.48 639.39 35.25 3.55 3.91 0.052 Analysis begun on: Tue Jul 16 12:54:08 2019 Analysis ended on: Tue Jul 16 12:54:24 2019 Total elapsed time: 00:00:16 POST_DEV EPA STORM WATER MANAGEMENT MODEL - VERSION 5.0 (Build 5.0.022) -------------------------------------------------------------- ********************************************************* NOTE: The summary statistics displayed in this report are based on results found at every computational time step, not just on results from each reporting time step. ********************************************************* **************** Analysis Options **************** Flow Units ............... CFS Process Models: Rainfall/Runoff ........ YES Snowmelt ............... NO Groundwater ............ NO Flow Routing ........... YES Ponding Allowed ........ NO Water Quality .......... NO Infiltration Method ...... GREEN_AMPT Flow Routing Method ...... KINWAVE Starting Date ............ OCT-01-1951 00:00:00 Ending Date .............. SEP-30-2008 23:00:00 Antecedent Dry Days ...... 0.0 Report Time Step ......... 01:00:00 Wet Time Step ............ 00:15:00 Dry Time Step ............ 04:00:00 Routing Time Step ........ 60.00 sec ************************** Volume Depth Runoff Quantity Continuity acre-feet inches ************************** --------- ------- Total Precipitation ...... 208.398 674.360 Evaporation Loss ......... 22.933 74.210 Infiltration Loss ........ 70.572 228.365 Surface Runoff ........... 116.713 377.673 Final Surface Storage .... 0.000 0.000 Continuity Error (%) ..... -0.873 ************************** Volume Volume Flow Routing Continuity acre-feet 10^6 gal ************************** --------- --------- Dry Weather Inflow ....... 0.000 0.000 Wet Weather Inflow ....... 116.713 38.033 Groundwater Inflow ....... 0.000 0.000 RDII Inflow .............. 0.000 0.000 External Inflow .......... 0.000 0.000 External Outflow ......... 116.685 38.023 Internal Outflow ......... 0.000 0.000 Storage Losses ........... 0.000 0.000 Initial Stored Volume .... 0.000 0.000 Final Stored Volume ...... 0.000 0.000 Continuity Error (%) ..... 0.024 ******************************** Highest Flow Instability Indexes ******************************** All links are stable. ************************* Routing Time Step Summary ************************* Minimum Time Step : 60.00 sec Average Time Step : 60.00 sec POST_DEV Maximum Time Step : 60.00 sec Percent in Steady State : 0.00 Average Iterations per Step : 1.00 *************************** Subcatchment Runoff Summary *************************** -------------------------------------------------------------------------------------------------------- Total Total Total Total Total Total Peak Runoff Precip Runon Evap Infil Runoff Runoff Runoff Coeff Subcatchment in in in in in 10^6 gal CFS -------------------------------------------------------------------------------------------------------- DMA-1D 674.36 0.00 81.95 21.50 577.72 5.35 0.41 0.857 DMA-2A(SM) 674.36 0.00 6.88 596.04 74.05 0.59 0.31 0.110 BR-3 674.36 15402.89 822.89 0.00 15312.70 5.32 0.42 0.952 DMA-1B 674.36 0.00 50.94 247.65 382.23 3.37 0.37 0.567 DMA-1C 674.36 0.00 78.35 47.62 555.20 7.63 0.60 0.823 BR-2 674.36 15205.17 694.80 2050.69 13156.94 2.92 0.38 0.829 BR-1 674.36 557.47 412.72 276.03 546.16 0.27 0.74 0.443 BR-4 674.36 28132.37 871.74 0.00 28059.63 7.61 0.62 0.974 DMA-1B(Pavers) 674.36 0.00 2.27 672.29 0.01 0.00 0.00 0.000 DMA-1D(Pavers) 674.36 0.00 2.27 672.29 0.01 0.00 0.00 0.000 DMA-1E 674.36 0.00 87.11 0.00 592.58 21.32 1.60 0.879 DMA-1A+Pavers 674.36 0.00 56.17 609.37 14.15 0.28 0.83 0.021 *********************** LID Performance Summary *********************** ------------------------------------------------------------------------------------------------------------------ Total Evap Infil Surface Drain Init. Final Pcnt. Inflow Loss Loss Outflow Outflow Storage Storage Error Subcatchment LID Control in in in in in in in ------------------------------------------------------------------------------------------------------------------ BR-3 BR-3 16077.25 823.12 0.00 2641.89 12675.01 0.00 0.00 -0.39 BR-2 BR-2 15879.53 694.60 2050.11 2268.89 10884.29 0.00 0.00 -0.12 BR-1 BR-1 1231.83 412.64 275.98 220.41 325.64 0.00 0.00 -0.23 BR-4 BR-4 28806.73 871.75 0.00 9388.01 18672.01 0.00 0.00 -0.43 ****************** Node Depth Summary ****************** --------------------------------------------------------------------- Average Maximum Maximum Time of Max Depth Depth HGL Occurrence Node Type Feet Feet Feet days hr:min --------------------------------------------------------------------- POC-1 OUTFALL 0.00 0.00 0.00 0 00:00 VAULT STORAGE 0.12 7.56 7.56 18823 17:01 ******************* Node Inflow Summary ******************* ------------------------------------------------------------------------------------- Maximum Maximum Lateral Total Lateral Total Time of Max Inflow Inflow Inflow Inflow Occurrence Volume Volume Node Type CFS CFS days hr:min 10^6 gal 10^6 gal ------------------------------------------------------------------------------------- POC-1 OUTFALL 0.31 3.70 18823 17:00 0.591 38.021 VAULT STORAGE 3.41 3.41 18823 17:00 37.439 37.439 ********************** Node Surcharge Summary POST_DEV ********************** Surcharging occurs when water rises above the top of the highest conduit. --------------------------------------------------------------------- Max. Height Min. Depth Hours Above Crown Below Rim Node Type Surcharged Feet Feet --------------------------------------------------------------------- VAULT STORAGE 499679.02 7.558 0.442 ********************* Node Flooding Summary ********************* No nodes were flooded. ********************** Storage Volume Summary ********************** -------------------------------------------------------------------------------------------- Average Avg E&I Maximum Max Time of Max Maximum Volume Pcnt Pcnt Volume Pcnt Occurrence Outflow Storage Unit 1000 ft3 Full Loss 1000 ft3 Full days hr:min CFS -------------------------------------------------------------------------------------------- VAULT 0.151 1 0 9.864 94 18823 17:00 3.40 *********************** Outfall Loading Summary *********************** ----------------------------------------------------------- Flow Avg. Max. Total Freq. Flow Flow Volume Outfall Node Pcnt. CFS CFS 10^6 gal ----------------------------------------------------------- POC-1 9.66 0.03 3.70 38.021 ----------------------------------------------------------- System 9.66 0.03 3.70 38.021 ******************** Link Flow Summary ******************** ----------------------------------------------------------------------------- Maximum Time of Max Maximum Max/ Max/ |Flow| Occurrence |Veloc| Full Full Link Type CFS days hr:min ft/sec Flow Depth ----------------------------------------------------------------------------- OUTLET DUMMY 3.40 18823 17:01 ************************* Conduit Surcharge Summary ************************* No conduits were surcharged. Analysis begun on: Mon Dec 16 16:34:54 2019 Analysis ended on: Mon Dec 16 16:35:21 2019 Total elapsed time: 00:00:27 Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 25 of 27 ATTACHMENT 3 Structural BMP Maintenance Information Use this checklist to ensure the required information has been included in the Structural BMP Maintenance Information Attachment: Preliminary Design/Planning/CEQA level submittal: Attachment 3 must identify: ☐ Typical maintenance indicators and actions for proposed structural BMP(s) based on Section 7.7 of the BMP Design Manual Final Design level submittal: Attachment 3 must identify: ☑ Specific maintenance indicators and actions for proposed structural BMP(s). This shall be based on Section 7.7 of the BMP Design Manual and enhanced to reflect actual proposed components of the structural BMP(s) ☑ How to access the structural BMP(s) to inspect and perform maintenance ☑ Features that are provided to facilitate inspection (e.g., observation ports, cleanouts, silt posts, or other features that allow the inspector to view necessary components of the structural BMP and compare to maintenance thresholds) ☑ Manufacturer and part number for proprietary parts of structural BMP(s) when applicable ☑ Maintenance thresholds for BMPs subject to siltation or heavy trash(e.g., silt level posts or other markings shall be included in all BMP components that will trap and store sediment, trash, and/or debris, so that the inspector may determine how full the BMP is, and the maintenance personnel may determine where the bottom of the BMP is . If required, posts or other markings shall be indicated and described on structural BMP plans.) ☑ Recommended equipment to perform maintenance ☑ When applicable, necessary special training or certification requirements for inspection and maintenance personnel such as confined space entry or hazardous waste management c:~Commercial Development Resources Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 26 of 27 Summary of BMP Inspection/Maintenance BMP Reponsible Party(s) Inspection/ Maintenance Activities Required Minimum Frequency of Activities Biofiltration Basin w/ Partial Retention BMP No. 1 BMP No. 2 Project Owner Inspect for and remove accumulated trash, sediment, and debris as necessary. Inspect for poor vegetation establishment or erosion, and overgrown vegetation. Inspect for standing water and repair or de-clog as needed. Maintain at least once per year. Inspect at least twice per year, prior to start of rainy season (Oct. 1st) and after significant storm events. Biofiltration Basin BMP No. 3 BMP No. 4 Project Owner Inspect for and remove accumulated trash, sediment, and debris as necessary. Inspect for poor vegetation establishment or erosion, and overgrown vegetation. Inspect for standing water and repair or de-clog as needed. Maintain at least once per year. Inspect at least twice per year, prior to start of rainy season (Oct. 1st) and after significant storm events. Modular Wetland System BMP No. 5 Project Owner Inspect for and remove accumulated trash, sediment, and debris as necessary. Clear obstructions if standing water or inlet clogged. Maintain at least once per year. Inspect at least twice per year, prior to start of rainy season (Oct. 1st) and after significant storm events. Underground Detention System BMP No. 6 Project Owner Inspect for and remove accumulated trash, sediment, and debris as necessary. Clear obstructions if standing water or inlet clogged. Maintain at least once per year. Inspect at least twice per year, prior to start of rainy season (Oct. 1st) and after significant storm events. c:~Commercial Development Resources www.modularwetlands.com Inspection Guidelines for Modular Wetland System - Linear Inspection Summary o Inspect Pre-Treatment, Biofiltration and Discharge Chambers – average inspection interval is 6 to 12 months. (15 minute average inspection time). o NOTE: Pollutant loading varies greatly from site to site and no two sites are the same. Therefore, the first year requires inspection monthly during the wet season and every other month during the dry season in order to observe and record the amount of pollutant loading the system is receiving. System Diagram Access to separation chamber and pre-filter cartridges 1 Pre-treatment Chamber 2 Biofiltration Chamber 3 Discharge Chamber Access to discharge chamber and orifice control Curb Inlet Pre·filter Cartridge Vertical Underdrain Manifold OioMedio GREEN M rlond MEDIA ~ MODULAP. WETLANDS Drain-Down Line Flow Control Riser www.modularwetlands.com Inspection Overview As with all stormwater BMPs inspection and maintenance on the MWS Linear is necessary. Stormwater regulations require that all BMPs be inspected and maintained to ensure they are operating as designed to allow for effective pollutant removal and provide protection to receiving water bodies. It is recommended that inspections be performed multiple times during the first year to assess the site specific loading conditions. This is recommended because pollutant loading and pollutant characteristics can vary greatly from site to site. Variables such as nearby soil erosion or construction sites, winter sanding on roads, amount of daily traffic and land use can increase pollutant loading on the system. The first year of inspections can be used to set inspection and maintenance intervals for subsequent years to ensure appropriate maintenance is provided. Without appropriate maintenance a BMP will exceed its storage capacity which can negatively affect its continued performance in removing and retaining captured pollutants. Inspection Equipment Following is a list of equipment to allow for simple and effective inspection of the MWS Linear: Modular Wetland Inspection Form Flashlight Manhole hook or appropriate tools to remove access hatches and covers Appropriate traffic control signage and procedures Measuring pole and/or tape measure. Protective clothing and eye protection. 7/16” open or closed ended wrench. Large permanent black marker (initial inspections only – first year) Note: entering a confined space requires appropriate safety and certification. It is generally not required for routine inspections of the system. MODULAP. WETLANDS www.modularwetlands.com Inspection Steps The core to any successful stormwater BMP maintenance program is routine inspections. The inspection steps required on the MWS Linear are quick and easy. As mentioned above the first year should be seen as the maintenance interval establishment phase. During the first year more frequent inspections should occur in order to gather loading data and maintenance requirements for that specific site. This information can be used to establish a base for long term inspection and maintenance interval requirements. The MWS Linear can be inspected though visual observation without entry into the system. All necessary pre-inspection steps must be carried out before inspection occurs, especially traffic control and other safety measures to protect the inspector and near-by pedestrians from any dangers associated with an open access hatch or manhole. Once these access covers have been safely opened the inspection process can proceed: Prepare the inspection form by writing in the necessary information including project name, location, date & time, unit number and other info (see inspection form). Observe the inside of the system through the access hatches. If minimal light is available and vision into the unit is impaired utilize a flashlight to see inside the system and all of its chambers. Look for any out of the ordinary obstructions in the inflow pipe, pre-treatment chamber, biofiltration chamber, discharge chamber or outflow pipe. Write down any observations on the inspection form. Through observation and/or digital photographs estimate the amount of trash, debris and sediment accumulated in the pre-treatment chamber. Utilizing a tape measure or measuring stick estimate the amount of trash, debris and sediment in this chamber. Record this depth on the inspection form. MODULAP. WETLANDS www.modularwetlands.com Through visual observation inspect the condition of the pre-filter cartridges. Look for excessive build-up of sediments on the cartridges, any build-up on the top of the cartridges, or clogging of the holes. Record this information on the inspection form. The pre-filter cartridges can further be inspected by removing the cartridge tops and assessing the color of the BioMediaGREEN filter cubes (requires entry into pre-treatment chamber – see notes above regarding confined space entry). Record the color of the material. New material is a light green in color. As the media becomes clogged it will turn darker in color, eventually becoming dark brown or black. Using the below color indicator record the percentage of media exhausted. The biofiltration chamber is generally maintenance free due to the system’s advanced pre- treatment chamber. For units which have open planters with vegetation it is recommended that the vegetation be inspected. Look for any plants that are dead or showing signs of disease or other negative stressors. Record the general health of the plants on the inspection and indicate through visual observation or digital photographs if trimming of the vegetation is needed. The discharge chamber houses the orifice control structure, drain down filter and is connected to the outflow pipe. It is important to check to ensure the orifice is in proper operating conditions and free of any obstructions. It is also important to assess the condition of the drain down filter media which utilizes a block form of the BioMediaGREEN. Assess in the same manner as the cubes in the Pre-Filter Cartridge as mentioned above. Generally, the discharge chamber will be clean and free of debris. Inspect the water marks on the side walls. If possible, inspect the discharge chamber during a rain event to assess the amount of flow leaving the system while it is at 100% capacity (pre-treatment chamber water level at peak HGL). The water level of the flowing water should be compared to the watermark level on the side walls which is an indicator of the highest discharge rate the system achieved when initially installed. Record on the form is there is any difference in level from watermark in inches. 0% -- Percent Clogged -- 100% New BioMediaGREEN Exhausted BioMediaGREEN 85% MODULAP. WETLANDS www.modularwetlands.com NOTE: During the first few storms the water level in the outflow chamber should be observed and a 6” long horizontal watermark line drawn (using a large permanent marker) at the water level in the discharge chamber while the system is operating at 100% capacity. The diagram below illustrates where a line should be drawn. This line is a reference point for future inspections of the system: Water level in the discharge chamber is a function of flow rate and pipe size. Observation of water level during the first few months of operation can be used as a benchmark level for future inspections. The initial mark and all future observations shall be made when system is at 100% capacity (water level at maximum level in pre-treatment chamber). If future water levels are below this mark when system is at 100% capacity this is an indicator that maintenance to the pre-filter cartridges may be needed. Finalize inspection report for analysis by the maintenance manager to determine if maintenance is required. Water Level Mark Water Level Marks Using a permanent marker draw a 6 inch long horizontal line, as shown, at the higher water level in the MWS Linear discharge chamber. MODULAR WETLANDS www.modularwetlands.com Maintenance Indicators Based upon observations made during inspection, maintenance of the system may be required based on the following indicators: Missing or damaged internal components or cartridges. Obstructions in the system or its inlet or outlet. Excessive accumulation of floatables in the pre-treatment chamber in which the length and width of the chamber is fully impacted more than 18”. Excessive accumulation of sediment in the pre-treatment chamber of more than 6” in depth. MODULAP. WETLANDS www.modularwetlands.com Excessive accumulation of sediment on the BioMediaGREEN media housed within the pre- filter cartridges. The following chart shows photos of the condition of the BioMediaGREEN contained within the pre-filter cartridges. When media is more than 85% clogged replacement is required. Excessive accumulation of sediment on the BioMediaGREEN media housed within the drain down filter. The following photos show of the condition of the BioMediaGREEN contained within the drain down filter. When media is more than 85% clogged replacement is required. 0% -- Percent Clogged -- 100% New BioMediaGREEN Exhausted BioMediaGREEN 85% MODULAP. WETLANDS www.modularwetlands.com Overgrown vegetation. Water level in discharge chamber during 100% operating capacity (pre-treatment chamber water level at max height) is lower than the watermark by 20%. MODULAP. WETLANDS www.modularwetlands.com Inspection Notes 1. Following maintenance and/or inspection, it is recommended the maintenance operator prepare a maintenance/inspection record. The record should include any maintenance activities performed, amount and description of debris collected, and condition of the system and its various filter mechanisms. 2. The owner should keep maintenance/inspection record(s) for a minimum of five years from the date of maintenance. These records should be made available to the governing municipality for inspection upon request at any time. 3. Transport all debris, trash, organics and sediments to approved facility for disposal in accordance with local and state requirements. 4. Entry into chambers may require confined space training based on state and local regulations. 5. No fertilizer shall be used in the Biofiltration Chamber. 6. Irrigation should be provided as recommended by manufacturer and/or landscape architect. Amount of irrigation required is dependent on plant species. Some plants may not require irrigation after initial establishment. MODULAP. WETLANDS www.modularwetlands.com Maintenance Guidelines for Modular Wetland System - Linear Maintenance Summary o Remove Sediment from Pre-Treatment Chamber – average maintenance interval is 12 to 24 months. (10 minute average service time). o Replace Pre-Filter Cartridge Media – average maintenance interval 12 to 24 months. (10-15 minute per cartridge average service time). o Trim Vegetation – average maintenance interval is 6 to 12 months. (Service time varies). System Diagram Access to separation chamber and pre-filter cartridge 1 Pre-treatment Chamber 2 Biofiltration Chamber 3 Discharge Chamber Curb Inlet Pre-filter Cartridge Vertical Underdrain Manifold GioMedia GREEN \}.ktlond MEDIA 0 0 0 Drain-Down Line ~ MODULAP. WETLANDS www.modularwetlands.com Maintenance Overview The time has come to maintain your Modular Wetland System Linear (MWS Linear). To ensure successful and efficient maintenance on the system we recommend the following. The MWS Linear can be maintained by removing the access hatches over the systems various chambers. All necessary pre-maintenance steps must be carried out before maintenance occurs, especially traffic control and other safety measures to protect the inspector and near-by pedestrians from any dangers associated with an open access hatch or manhole. Once traffic control has been set up per local and state regulations and access covers have been safely opened the maintenance process can begin. It should be noted that some maintenance activities require confined space entry. All confined space requirements must be strictly followed before entry into the system. In addition the following is recommended: Prepare the maintenance form by writing in the necessary information including project name, location, date & time, unit number and other info (see maintenance form). Set up all appropriate safety and cleaning equipment. Ensure traffic control is set up and properly positioned. Prepare a pre-checks (OSHA, safety, confined space entry) are performed. Maintenance Equipment Following is a list of equipment required for maintenance of the MWS Linear: Modular Wetland Maintenance Form Manhole hook or appropriate tools to access hatches and covers Protective clothing, flashlight and eye protection. 7/16” open or closed ended wrench. Vacuum assisted truck with pressure washer. Replacement BioMediaGREEN for Pre-Filter Cartridges if required (order from manufacturer). MODULAP. WETLANDS www.modularwetlands.com Maintenance Steps 1. Pre-treatment Chamber (bottom of chamber) A. Remove access hatch or manhole cover over pre-treatment chamber and position vacuum truck accordingly. B. With a pressure washer spray down pollutants accumulated on walls and pre-filter cartridges. C. Vacuum out Pre-Treatment Chamber and remove all accumulated pollutants including trash, debris and sediments. Be sure to vacuum the floor until pervious pavers are visible and clean. D. If Pre-Filter Cartridges require media replacement move onto step 2. If not, replace access hatch or manhole cover. Removal of access hatch to gain access below. Insertion of vacuum hose into separation chamber. Removal of trash, sediment and debris. Fully cleaned separation chamber. MODULAP. WETLANDS www.modularwetlands.com 2. Pre-Filter Cartridges (attached to wall of pre-treatment chamber) A. After finishing step 1 enter pre-treatment chamber. B. Unscrew the two bolts holding the lid on each cartridge filter and remove lid. C. Place the vacuum hose over each individual media filter to suck out filter media. D. Once filter media has been sucked use a pressure washer to spray down inside of the cartridge and it’s containing media cages. Remove cleaned media cages and place to the side. Once removed the vacuum hose can be inserted into the cartridge to vacuum out any remaining material near the bottom of the cartridge. Pre-filter cartridges with tops on. Inside cartridges showing media filters ready for replacement. Vacuuming out of media filters. ~ MODULAP. WETLANDS www.modularwetlands.com E. Reinstall media cages and fill with new media from manufacturer or outside supplier. Manufacturer will provide specification of media and sources to purchase. Utilize the manufacture provided refilling trey and place on top of cartridge. Fill trey with new bulk media and shake down into place. Using your hands slightly compact media into each filter cage. Once cages are full removed refilling trey and replace cartridge top ensuring bolts are properly tightened. F. Exit pre-treatment chamber. Replace access hatch or manhole cover. 3. Biofiltration Chamber (middle vegetated chamber) A. In general, the biofiltration chamber is maintenance free with the exception of maintaining the vegetation. Using standard gardening tools properly trim back the vegetation to healthy levels. The MWS Linear utilizes vegetation similar to surrounding landscape areas therefore trim vegetation to match surrounding vegetation. If any plants have died replace plants with new ones: Refilling trey for media replacement. Refilling trey on cartridge with bulk media. ~ MODULAP. WETLANDS www.modularwetlands.com 4. Discharge Chamber (contains drain down cartridge & connected to pipe) A. Remove access hatch or manhole cover over discharge chamber. B. Enter chamber to gain access to the drain down filter. Unlock the locking mechanism and left up drain down filter housing to remove used BioMediaGREEN filter block as shown below: C. Insert new BioMediaGREEN filter block and lock drain down filter housing back in place. Replace access hatch or manhole cover over discharge chamber. MODULAP. WETLANDS www.modularwetlands.com Inspection Notes 1. Following maintenance and/or inspection, it is recommended the maintenance operator prepare a maintenance/inspection record. The record should include any maintenance activities performed, amount and description of debris collected, and condition of the system and its various filter mechanisms. 2. The owner should keep maintenance/inspection record(s) for a minimum of five years from the date of maintenance. These records should be made available to the governing municipality for inspection upon request at any time. 3. Transport all debris, trash, organics and sediments to approved facility for disposal in accordance with local and state requirements. 4. Entry into chambers may require confined space training based on state and local regulations. 5. No fertilizer shall be used in the Biofiltration Chamber. 6. Irrigation should be provided as recommended by manufacturer and/or landscape architect. Amount of irrigation required is dependent on plant species. Some plants may not require irrigation after initial establishment. MODULAP. WETLANDS www.modularwetlands.com Inspection Form Modular Wetland System, Inc. P. 760.433-7640 F. 760-433-3176 E. Info@modularwetlands.com MODULAR WETLANDS Cl For Office Use Only (city) (Zip Code)(Reviewed By) Owner / Management Company (Date) Contact Phone ( )_ Inspector Name Date / /Time AM / PM Weather Condition Additional Notes Yes Depth: Yes No Modular Wetland System Type (Curb, Grate or UG Vault):Size (22', 14' or etc.): Other Inspection Items: Storm Event in Last 72-hours? No Yes Type of Inspection Routine Follow Up Complaint Storm Office personnel to complete section to the left. 2972 San Luis Rey Road, Oceanside, CA 92058 P (760) 433-7640 F (760) 433-3176 Inspection Report Modular Wetlands System Is the filter insert (if applicable) at capacity and/or is there an accumulation of debris/trash on the shelf system? Does the cartridge filter media need replacement in pre-treatment chamber and/or discharge chamber? Any signs of improper functioning in the discharge chamber? Note issues in comments section. Chamber: Is the inlet/outlet pipe or drain down pipe damaged or otherwise not functioning properly? Structural Integrity: Working Condition: Is there evidence of illicit discharge or excessive oil, grease, or other automobile fluids entering and clogging the unit? Is there standing water in inappropriate areas after a dry period? Damage to pre-treatment access cover (manhole cover/grate) or cannot be opened using normal lifting pressure? Damage to discharge chamber access cover (manhole cover/grate) or cannot be opened using normal lifting pressure? Does the MWS unit show signs of structural deterioration (cracks in the wall, damage to frame)? Project Name Project Address Inspection Checklist CommentsNo Does the depth of sediment/trash/debris suggest a blockage of the inflow pipe, bypass or cartridge filter? If yes, specify which one in the comments section. Note depth of accumulation in in pre-treatment chamber. Is there a septic or foul odor coming from inside the system? Is there an accumulation of sediment/trash/debris in the wetland media (if applicable)? Is it evident that the plants are alive and healthy (if applicable)? Please note Plant Information below. Sediment / Silt / Clay Trash / Bags / Bottles Green Waste / Leaves / Foliage Waste:Plant Information No Cleaning Needed Recommended Maintenance Additional Notes: Damage to Plants Plant Replacement Plant Trimming Schedule Maintenance as Planned Needs Immediate Maintenance CLEAN. !NVPRONM(NTAL StltVtCE.$, INC. ---- □ □ □ □ □ □ www.modularwetlands.com Maintenance Report Modular Wetland System, Inc. P. 760.433-7640 F. 760-433-3176 E. Info@modularwetlands.com MODULAP. WETLANDS For Office Use Only (city) (Zip Code)(Reviewed By) Owner / Management Company (Date) Contact Phone ( )_ Inspector Name Date / / Time AM / PM Weather Condition Additional Notes Site Map # Comments: 2972 San Luis Rey Road, Oceanside, CA 92058 P. 760.433.7640 F. 760.433.3176 Inlet and Outlet Pipe Condition Drain Down Pipe Condition Discharge Chamber Condition Drain Down Media Condition Plant Condition Media Filter Condition Long: MWS Sedimentation Basin Total Debris Accumulation Condition of Media 25/50/75/100 (will be changed @ 75%) Operational Per Manufactures' Specifications (If not, why?) Lat:MWS Catch Basins GPS Coordinates of Insert Manufacturer / Description / Sizing Trash Accumulation Foliage Accumulation Sediment Accumulation Type of Inspection Routine Follow Up Complaint Storm Storm Event in Last 72-hours? No Yes Office personnel to complete section to the left. Project Address Project Name Cleaning and Maintenance Report Modular Wetlands SystemCLEAN. ~ MODULA R E.NV/RONME.NTAL SE.RVICE.S , INC. WETLANDS ---- □ □ □ □ □ □ Underground stormwater detention and infiltration systems must be inspected and maintained at regular intervals for purposes of performance and longevity. Inspection Inspection is the key to effective maintenance of CMP detention systems and is easily performed. Contech recommends ongoing, quarterly inspections. The rate at which the system collects pollutants will depend more on site specific activities rather than the size or configuration of the system. Inspections should be performed more often in equipment washdown areas, in climates where sanding and/or salting operations take place, and in other various instances in which one would expect higher accumulations of sediment or abrasive/corrosive conditions. A record of each inspection is to be maintained for the life of the system. Maintenance CMP detention systems should be cleaned when an inspection reveals accumulated sediment or trash is clogging the discharge orifice. Accumulated sediment and trash can typically be evacuated through the manhole over the outlet orifice. If maintenance is not performed as recommended, sediment and trash may accumulate in front of the outlet orifice. Manhole covers should be securely seated following cleaning activities. Contech suggests that all systems be designed with an access/inspection manhole situated at or near the inlet and the outlet orifice. Should it be necessary to get inside the system to perform maintenance activities, all appropriate precautions regarding confined space entry and OSHA regulations should be followed. Systems are to be rinsed, including above the spring line, annually soon after the spring thaw, and after any additional use of salting agents, as part of the maintenance program for all systems where salting agents may accumulate inside the pipe. Maintaining an underground detention or infiltration system is easiest when there is no flow entering the system. For this reason, it is a good idea to schedule the cleanout during dry weather. The foregoing inspection and maintenance efforts help ensure underground pipe systems used for stormwater storage continue to function as intended by identifying recommended regular inspection and maintenance practices. Inspection and maintenance related to the structural integrity of the pipe or the soundness of pipe joint connections is beyond the scope of this guide. Contech® CMP Detention Inspection and Maintenance Guide CMP MAINTENANCE GUIDE 2/17 PDF © 2017 Contech Engineered Solutions LLC All rights reserved. Printed in USA. ENGINEERED SOLUTIONS 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 CMP DETENTION SYSTEMS Underground stormwater detention and infiltration systems must be inspected and maintained at regular intervals for purposes of performance and longevity. Inspection Inspection is the key to effective maintenance of CMP detention systems and is easily performed. Contech recommends ongoing, annual inspections. Sites with high trash load or small outlet control orifices may need more frequent inspections. The rate at which the system collects pollutants will depend more on- site specific activities rather than the size or configuration of the system. Inspections should be performed more often in equipment washdown areas, in climates where sanding and/or salting operations take place, and in other various instances in which one would expect higher accumulations of sediment or abrasive/ corrosive conditions. A record of each inspection is to be maintained for the life of the system. 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. CMP MAINTENANCE GUIDE 10/19 PDF © 2019 CONTECH ENGINEERED SOLUTIONS LLC, A QUIKRETE COMPANY ALL RIGHTS RESERVED. PRINTED IN USA. Maintenance CMP detention systems should be cleaned when an inspection reveals accumulated sediment or trash is clogging the discharge orifice. Accumulated sediment and trash can typically be evacuated through the manhole over the outlet orifice. If maintenance is not performed as recommended, sediment and trash may accumulate in front of the outlet orifice. Manhole covers should be securely seated following cleaning activities. Contech suggests that all systems be designed with an access/inspection manhole situated at or near the inlet and the outlet orifice. Should it be necessary to get inside the system to perform maintenance activities, all appropriate precautions regarding confined space entry and OSHA regulations should be followed. Annual inspections are best practice for all underground systems. During this inspection if evidence of salting/de-icing agents is observed within the system, it is best practice for the system to be rinsed, including above the spring line soon after the spring thaw as part of the maintenance program for the system. Maintaining an underground detention or infiltration system is easiest when there is no flow entering the system. For this reason, it is a good idea to schedule the cleanout during dry weather. The foregoing inspection and maintenance efforts help ensure underground pipe systems used for stormwater storage continue to function as intended by identifying recommended regular inspection and maintenance practices. Inspection and maintenance related to the structural integrity of the pipe or the soundness of pipe joint connections is beyond the scope of this guide. Contech® CMP Detention Inspection and Maintenance Guide ENGINEERED SOLUTIONS CMP DETENTION SYSTEMS Priority Development Project (PDP) SWQMP BMW of Carlsbad PDP SWQMP 27 of 27 ATTACHMENT 4 City standard Single Sheet BMP (SSBMP) Exhibit [Use the City’s standard Single Sheet BMP Plan.] c:~Commercial Development Resources . . --7=1 . / / I /, I • I• 8 ~ i. I I t ~/ ·Jrf ----- I " I l G:::~:; I -~ ,,,,,,.\ i -L--,.----1 • I ' I ' ~ " ' \O'I-ROOF DOWN DRAIN TO BM P-3 0.520AC ~==== I --~R=O=O~F~S~T=O~R=M~D=R~A=IN~_ -SYSTEM PER MEP PLANS I-----, ----~ i½@i I • I ROOFOOWN I --DRAIN TO BMP-5 fl I I ------,1 I ----ccjl ~---= I ROOF STORM DRAIN i---ccsy"sceTccE-"cMccPeeEccRc-M"'EceP-ePc'-LA~N=s ~ I I ------,1 I -----,1 ----~ I I _____ ,----- ~ I I I CAR RAMP FLOWS TO OMA-1 C if-@l I i---- 1 0 ROOF DOWN DRAIN TO BMP-5 I 0 L ___ _ ROOF STORM DRAIN SYSTEM PER MEP PLANS ~!__ I " I I I I i-- ROOF STORM DRAIN SYSTEM PER MEP PLANS ] Ni t-----+---' 1 I I 1~------1c------l ~O~M~A~-~10~ 1~~n r ~ I ' I ' 0.404AC -' -I ' I 8 I I I " OMA-1E 1.321 AC PROPOSED BU ILDING W/ ROOFTOP PARKING -.,,--.. _ ,._,,,_ .. _ "' --.,,._ __ "' --.. -- I I I 7 ' I • •--:-A • • • ~ I 1/, . OMA-2A -_.., 0.040AC .: -- _, ~ilit -~ / / ----=ac+-..b .. __ ,. __ ,,, I \_ ' . ----t----------1-----1 --------AUTO CENTER CT I ---~.:::-~ u .. J\i._ "--------------------- 8 _" __ '" __ I I L __ _ LJ 7 -. . . -. . . . --. . ------:-0]1 --. -. · :·102 ·: ..... :_A: . . . . . r7 '-=-----;z;:. -cF,L4=¾~lsc I I . x· • ' 8 4 4 " OMA-1B 0.423AC ·r--"" P=\=/c~-~---b~--=-~~ ~ r-~ / 1..--- / , ~ ' \ '\\ ',\I I I I I I 0.023AC I C~Commercial Development Resources Today's Ideas. Tomorrow's Reality. 4121 Wasl<1rl1 FlaGB #1 12 N&Ytport Baach CA g;,550 T 949-610-8997 , . .,,,.,..,,_cDRVM~tcom SWMP NO.~T=BO~---- PARTY RESPONSIB LE FOR MAINTENANCE NAM E: AUTONATION INC. ADDRESS: 200 SW 1ST AVE 14TH FLOOR CONTACT: CLIFF POWELL FORT LAUDERDALE FL 33301 PHONE NO · 1654) 769-6000 PLAN PREPARED BY ----------B-. NAME: AARON M. ALBERTSON PE C/2JS• ,;i0 SIGNATURE COMPANY: COMMERCIAL DEVELOPMENT RESOURCES ADDRESS: 4121 WESTERLY PLACE SU ITE 112 NEWPORT BEAC H. CA 92660 PHONE NO · 1949) 610-8997 CERTIFICATION-R.C.E. 65513 BM P NOTES: 1. 2. 3 . 4. 5. 6. THESE BMPS ARE MANDATORY TO BE INSTALLED PER MANUFACTURER'S RECOMMENDATIONS OR THESE PLANS. NO CHANGES TO THE PROPOSED BMPS ON THIS SHEET WITHOUT PR IOR APPROVAL FROM THE CITY ENGINEER. NO SUBSTITUTIONS TO THE MATERIAL OR TYPES OR PLANTING TYPES WITHOUT PRIOR APPROVAL FROM THE CITY ENGINEER. NO OCCUPANCY WILL BE GRANTED UNTIL THE CITY INSPECTION STAFF HAS INSP ECTED THIS PROJECT FOR APPROPRIATE BMP CONSTRUCTION ANO INSTALLATION . REFER TO MAINTENANCE AGREEMENT DOCUMENT. SEE PROJECT SWMP FOR ADD ITIONAL INFORMATION. -" '--r-h l--1--,W=! I I I I I - . - . -' . • -iS 7 ---. • -. . \ /i I /1 BMP ID# I I I I I I I I I I BMPTYPE 20 GEOTECHNICAL NOTES • HYOROLOGIC SOIL GROUP B • INFILTRATION : 0.041 IN/HR • SOIL EXPANS IVE POTENTIAL: VERY LOW • APPROXIMATE DEPTH TO GROUNDWATER: >50' 0 20 40 PERMANENT WATER QUALITY TREATMENT FACILITY KEEP OUR WATER\IVAYS CLEAN GRAPHIC SCALE SCALE: 1"= 20' MAINTAIN WITH CARE -NO MODIFICATIONS \IV'ITHOUT AGENCY APPROVAL BMP TABLE SYMBOL CASQA NO. QUANTITY DRAWING NO. SHEET NO.(S) b.. WATER QUALITY SIGN NOT TO SCALE INSPECTION* FREQUENCY MAINTENANCE * FREQUENCY HYDROMODIFICATION & TREATMENT CONTROL (ii BIOFILTRATION BASIN WI \..'_) PARTIAL RETENTION 0 BIOFILTRATION BASIN WI PARTIAL RETENTION TC-32 812 SF TC-32 359 SF 529-6A 08, 11 SEMI-ANNUALLY ANNUALLY 529-6A 08, 11 SEMI-ANNUALLY ANNUALLY I f-------+--------+--~~--+----+-----+-----+-------+--------+-----___, ~ BIOFILTRATION BASIN WI I I I I I I I I \:'_} IMPERMEABLE LINER 0 BIOFILTRATION BASIN WI IMPERMEABLE LINER TREATMENT CONTROL 0 BIOFILTRATION: 111 111 MODULAR WETLAND SYSTEM (MWS) HYDROMODIFICATION DETENTION VAULT LOW IMPACT DESIGN (L.I.D.) 0 0 PERMEABLE PAVERS LANDSCAPE WI NATIVE/DROUGHT TOLERANT SPECIES SOURCE CONTROL 0 TRASH ENCLOSURE r1 IN LET STENCIL/ SIGNAGE SEE DETAI L TC-32 576 SF 529-6A 08, 11 SEMI-ANNUALLY ANNUALLY TC-32 455 SF 529-6A 08, 11 SEMI-ANNUALLY ANNUALLY BF-3 1 EA. 529-6A 08, 11 SEMI-ANNUALLY ANNUALLY MP-50 2 EA. 529-6A 08, 12 SEMI-ANNUALLY ANNUALLY SD-20 15,776 SF 529-6A 04, 10 SEMI-ANNUALLY ANNUALLY SD-10 24,793 SF 529-6A 04 WEEKLY WEEKLY SD-32 1 EA. 529-6A 04 AS-NEEDED AS-NEEDED SD-13 4 EA. 529-6A 08 AS-NEEDED AS-NEEDED fsHml CITY OF CARLSBAD ~ i----1-----t-----------------+-----t---i----+-----,l__()_1__J~_E_N_G_I_N_EE_R_I_N_G_D_E_P_A_R_T_M_EN_T __ ~l___Q_1_J SINGLE SHEET BMP SITE PLAN BMW OF CARLSBAD 1060 AUTO CENTER COURT CARLSBAD, CA 92008 RECORD COPY PROJECT NO. MS2019-0003 DATE INITIAL ENGINEER OF WORK REVISION DESCRI PTION DATE INITIAL DATE INITIAL OTHER APPROVAL CITY APPROVAL I DRAWING NO, I INITIAL DATE 529-6A '" a N V,