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HomeMy WebLinkAboutHMP 15-01; MARTIN RESIDENCE; PRIORITY DEVELOPMENT PROJECT (PDP) STORM WATER MANAGEMENT PLAN (SWQMP); 2017-05-02rr' r-r 'LJ - /2JJI) Initial Date CITY OF CARLSBAD PRIORITY DEVELOPMENT PROJECT (PDP) PRELIMINARY STORM WATER QUALITY MANAGEMENT PLAN (SWQMP) FOR MARTIN RESIDENCE HMP 15-01 ENGINEER OF WORK: M'\ (GO ( No. 36190 \ Exp. 6/30/18 jJJ C IL RANDY R. BRÔWN RCE 36190 OF C PREPARED FOR: CAROLINE & NEIL MARTIN 1878 SHADETREE DRIVE SAN MARCOS, CA 92078 PREPARED BY: SOWARDS & BROWN ENGINEERING 2187 NEWCASTLE AVE. SUITE 103 CARDIFF, CA 92007 (760) 436-8500 I E I I I I I F I I I I I DATE: 5/02/17 RECEIVED MAY 112017 CITY OF CARLSBAD PLANN' D';SION I I TABLE OF CONTENTS I Certification Page Project Vicinity Map FORM E-34 Storm Water Standard Questionnaire ' Site Information FORM E-36 Standard Project Requirement Checklist Summary of PDP Structural BMPs ' Attachment 1: Backup for PDP Pollutant Control BMPs Attachment Ia: DMA Exhibit Attachment I b: Tabular Summary of DMAs and Design Capture Volume Calculations I Attachment Ic: Harvest and Use Feasibility Screening (when applicable) Attachment ld: Categorization of Infiltration Feasibility Condition (when applicable) Attachment le: Pollutant Control BMP Design Worksheets I Calculations I Attachment 2: Backup for PDP Hydromodification Control Measures Attachment 2a: Hydromodification Management Exhibit Attachment 2b: Management of Critical Coarse Sediment Yield Areas Attachment 2c: Geomorphic Assessment of Receiving Channels I Attachment 2d: Flow Control Facility Design Attachment 3: Structural BMP Maintenance Thresholds and Actions Attachment 4: Single Sheet BMP (SSBMP) Exhibit .1 I I I i 1 I I 11 '1 Date I Print Name I, 'I Ess/o7 rM %. No. 36190 xp. 6/30/18 1* I I CERTIFICATION PAGE 1 Martin Residence HMP 15-01 I I hereby declare that I am the Engineer in Responsible Charge of design of storm water BMPs for I 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 I 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 I responsibilities for project design. I Engineer of Work1V Signature, PE Number & Expiration Date I Zkit( r-kLd VICINITY MAP N. TS. THOMAS BROTHERS No. 1126—G7 I I FIGURE 2. 1 NOT TO SCALE I Si cos I I FIGURE 2.2 VICINI TY MAP N. IS. I I I , (-I, -- City of Carlsbad STORM WATER STANDARDS QUESTIONNAIRE E-34 Development Services Land Development Engineering 1635 Faraday Avenue (760) 602-2750 www.carlsbadca.gov Li 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 I (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. I 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 I 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: MARTIN RESIDENCE PROJECT ID: HMP 15-01 ADDRESS: Adams Street, Carlsbad CA 92008 APN: 206-200-03 The project is (check one): 7 New Development Eli Redevelopment The total proposed disturbed area is: 10,299 2 (_024_) acres The total proposed newly created and/or replaced impervious area is: 8,415 2 (_0.20 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 SWQMP#: Then, go to Step I 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 I [1 Ll ri I I I I I I, STEP I 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 LI 0 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. STEP 2 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: Designed and constructed to direct storm water runoff to adjacent vegetated areas, or other non- erodible permeable areas; El 0 Designed and constructed to be hydraulically disconnected from paved streets or roads; 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 LI i 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? U 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. I I I I I [1 I I L I I E-34 Page 2 of 4 REV 02/16 STEP 3 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 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, fl and public development projects on public or private land. 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 more of impervious surface? This includes commercial, industrial, residential, mixed-use, and public development projects on public or private land. 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 El ElI refreshment stands selling prepared foods and drinks for immediate consumption (Standard Industrial Classification (SIC) code 5812). 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 development project includes development on any natural slope that is twenty-five percent or greater. 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 El Z a land area or facility for the temporary parking or storage of motor vehicles used personally for business or for commerce. 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 street, road, highway freeway or driveway? A street, road, highway, freeway or driveway is any paved impervious surface used for the transportation of automobiles, trucks, motorcycles, and other vehicles. 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 II Eli 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).* 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 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. 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 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. Is your project a new or redevelopment project that results in the disturbance of one or more acres of land El W1 and are expected to generate pollutants post construction? 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 fl 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. I I Ii I I I:] I I I Fil I I E-34 Page 3 of 4 REV 02/16 STEP 4 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) = sq. ft. LI Total proposed newly created or replaced impervious area (B) = sq. ft. Percent impervious area created or replaced (BIA)*100 = % 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 BMP'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 fI 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. El 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. LI 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: Neil A Martin & Caroline S. Martin Applicant Title: Owners Date: Applicant Signature:i * Environmentally Sensitive Areas include but are not limited to all Clean Water Act Section 303(d) impaired 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. This Box for City Use Only City Concurrence: YES NO LI By: 0.,R1cK Date: /i717 Project ID: HrP i I I E-34 Page 4 of 4 REV 02/16 I 'I I I I I I $ I 1 I I [1 SITE INFORMATION CHECKLIST Project Summary Information Project Name Martin Residence Project ID HMP 15-01 Project Address Adams Street Carlsbad CA 92008 Assessor's Parcel Number(s) (APN(s)) 206-200-03 Project Watershed (Hydrologic Unit) Carlsbad 904.31 Parcel Area 0.47 Acres (20,347 Square Feet) Existing Impervious Area (subset of Parcel Area) 0 Acres (0 Square Feet) Area to be disturbed by the project (Project Area) 0.24 Acres (10,299 Square Feet) Project Proposed Impervious Area (subset of Project Area) 0.20 Acres (8,415 Square Feet) Project Proposed Pervious Area (subset of Project Area) 0.04 Acres (1,884 Square Feet) Note: Proposed Impervious Area + Proposed Pervious Area = Area to be Disturbed by the Project. This may be less than the Parcel Area. [1 I I I Li I 1 I I I Description Of Existing Site Condition and Drainage Patterns Current Status of the Site (select all that apply): U Existing development U Previously graded but not built out U Agricultural or other non-impervious use Vacant, undeveloped/natural Description I Additional Information: Existing Land Cover Includes (select all that apply): Vegetative Cover Non-Vegetated Pervious Areas U Impervious Areas Description /Additional Information: Underlying Soil belongs to Hydrologic Soil Group (select all that apply): U NRCS Type A NRCS Type B U NRCS Type C U NRCS Type D Approximate Depth to Groundwater (GW): U GW Depth <5 feet U 5 feet < GW Depth < 10 feet U l0 feet <GW Depth <20feet GW Depth > 20 feet Existing Natural Hydrologic Features (select all that apply): U Watercourses U Seeps U Springs Wetlands U None Description /Additional Information: Southerly end of subject lot extends into Agua Hedionda Lagoon. Li I I I I I E U I I 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]: In the existing condition, the site generally drains over natural landscape to the South down a hillside with a slope of 4:1 or less. The site drains directly to the Agua Hedionda Lagoon, and the Southerly boundary of the site extends roughly 47 feet South of the mean high tide line. There is no cross lot drainage to the West and minimal cross lot drainage to the East. There is onsite drainage from the North, over a slope in the Adams Street right-of-way. There is no onsite drainage from impervious areas. The project proposes to construct a single family residence and attached garage with an '5' shaped driveway. Stairs and concrete walkways will provide access on the East and West sides of the residence to the lower level patio and pool on the South side of the residence. A multi-level pad will be cut into the hillside, with retaining walls to support the change in grade. The proposed development does not extend into the 100' wetland buffer. Grades along the North property line will be adjusted to eliminate any onsite drainage from the North, and a pervious concrete sidewalk will be constructed in the right-of-way to reduce the impervious footprint. Runoff from the proposed roof and hardscape will be diverted to various planters around the residence. These planters will be built to function as biofiltration basins, and runoff from all the biofiltration basins will be collected in a vault under the lower level patio. An outlet structure built into the vault will provide proper hydromodification and flood control of the treated waters. Output from the vault will be routed to a slotted PVC pipe laid level and surrounded by gravel to mimic sheet flow. Treated flow from the developed area will comingle with the wetland buffer area flow prior to flowing into the Agua Hedionda Lagoon. I I I I i i I Description of Proposed Site Development and Drainage Patterns Project Description I Proposed Land Use and/or Activities: New single family residence to be developed on vacant property on Adams Street in Carlsbad fronting the Agua Hedionda Lagoon. The project scope of work includes grading, building construction of a two-story residence, pool, spa, landscape improvements, site retaining walls and drainage improvements. List/describe proposed impervious features of the project (e.g., buildings, roadways, parking lots, courtyards, athletic courts, other impervious features): Two story residence with garage, plus driveway and concrete walkways, stairs. List/describe proposed pervious features of the project (e.g., landscape areas): Several planters are incorporated around the residence. The 100' south of the constructed residence and hardscape will be a wetland buffer region with existing and proposed native vegetation. Does the project include grading and changes to site topography? Yes fl No Description / Additional Information: A multi-level pad will be cut into the hillside, with retaining walls to support the change in grade. Does the project include changes to site drainage (e.g., installation of new storm water conveyance systems)? Yes 1 No Description /Additional Information: Runoff from the proposed roof and hardscape will be diverted to various planters around the residence. These planters will be built to function as biofiltration basins, and runoff from all the biofiltration basins will be collected in a vault under the lower level patio. An outlet structure built into the vault will provide proper hydromodification and flood control of the treated waters. Output from the vault will be routed to a slotted PVC pipe laid level and surrounded by gravel to mimic sheet flow. Treated flow from the developed area will comingle with the wetland buffer area flow prior to flowing into the Agua Hedionda Lagoon. Identify whether any of the following features, activities, and/or pollutant sources will be present (select all that apply): On-site storm drain inlets U Interior floor drains and elevator shaft sump pumps El Interior parking garages Need for future indoor & structural pest control Landscape/Outdoor Pesticide Use Pools, spas, ponds, decorative fountains, and other water features El Food service LI Refuse areas LI Industrial processes LI Outdoor storage of equipment or materials El Vehicle and Equipment Cleaning Li Vehicle/Equipment Repair and Maintenance LI Fuel Dispensing Areas LI Loading Docks U Fire Sprinkler Test Water Miscellaneous Drain or Wash Water LI Plazas, sidewalks, and parking lots I I I F] I I I I I I I I I 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): This site drains directly to the Agua Hedionda Lagoon. 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 N/A 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 Aplendix B.6): 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 Pesticides x I Li I 1 I I I I I I I 1 Li 1 ification Do hydromodification management requirements apply (see Section 1.6 of the BMP Design I Manual)? . Yes, hydromodification management flow control structural BMPs required. Li No, the project will discharge runoff directly to existing underground storm drains discharging I directly to water storage reservoirs, lakes, enclosed embayments, or the Pacific Ocean. El 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, I enclosed embayments, or the Pacific Ocean. Li 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. I Description / Additional Information (to be provided if a 'No' answer has been selected above): I Critical Coarse Sediment Yield Areas* *This Section only required if hydromodification management requirements aoølv Based on the maps provided within the WMAA, do potential critical coarse sediment yield areas exist within the project drainage boundaries? O Yes No, No critical coarse sediment yield areas to be protected based on WMAA maps I If yes, have any of the optional analyses presented in Section 6.2 of the BMP Design Manual been performed? 0 6.2.1 Verification of Geomorphic Landscape Units (GLUs) Onsite I L] 6.2.2 Downstream Systems Sensitivity to Coarse Sediment 0 6.2.3 Optional Additional Analysis of Potential Critical Coarse Sediment Yield Areas Onsite Li No optional analyses performed, the project will avoid critical coarse sediment yield areas a identified based on WMAA maps If optional analyses were performed, what is the final result? LI No critical coarse sediment yield areas to be protected based on verification of GLUs onsite Li Critical coarse sediment yield areas exist but additional analysis has determined that protection is not required. Documentation attached in Attachment 8 of the SWQMP. Li 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: Iii I I 1 . -- 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 I 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. I There is one point of compliance POC-1 located at the outlet of an underground vault sized to meet hydromodification requirements. Water sheet flows from a flat perforated pipe over I natural terrain to the Agua Hedionda Lagoon. See the "Technical Memorandum: SWMM Modeling for Hydromodification Compliance of Martin Residence" report by Tory R. Walker Engineering dated March 1, 2017, under separate I cover, for sizing and drawdown calculations. See Vector Control Plan Memorandum dated May 2, 2017 from Tory R. Walker Engineering 1 (included as a separate attachment) Has a geomorphic assessment been performed for the receiving channel(s)? I . No, the low flow threshold is 0.1 Q2 (default low flow threshold) U Yes, the result is the low flow threshold is 0.1Q2 o Yes, the result is the low flow threshold is 0.3Q2 I D Yes, the result is the low flow threshold is 0.5Q2 If a geomorphic assessment has been performed, provide title, date, and preparer: I I I Discussion /Additional Information: (optional) I I 1 I U I I I 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. I There is a 100' wetland buffer that extends Northerly from the mean high tide line of Agua Hedionda Lagoon. Site development is limited to the portion of the lot North of the wetland I buffer limits. I 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. I I Pj I I I I I I I I I CCity of Carlsbad Development Services Land Development Engineering 1635 Faraday Avenue (760) 602-2750 www.carlsbadca.gov STANDARD PROJECT REQUIREMENT CHECKLIST E-36 Project Information Project Name: MARTIN RESIDENCE Project ID: HMP15-01 DWG No. or Building Permit No.: HMP 15-01 Source Control BMPs 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 EA 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 ll Yes J 0 No J 0 N/A Discussion/justification if SC-1 not implemented: SC-2 Storm Drain Stenciling or Signage 0 Yes LII No ll N/A Discussion/justification if SC-2 not implemented: Stenciling of small private drains is not feasible. SC-3 Protect Outdoor Materials Storage Areas from Rainfall, Run-On, Runoff, and Wind Dispersal 0 Yes 0 No ll N/A Discussion/justification if SC-3 not implemented: No outdoor material storage areas are proposed for this site. I E-36 Page 1 of 4 Revised 09/16 1 I I I I I Ii I I I I I I I I Source Control Requirement (continued) Applied? SC-4 Protect Materials Stored in Outdoor Work Areas from Rainfall, Run-On, Runoff, and Wind Dispersal D Yes 0 No lii N/A Discussion/justification if SC-4 not implemented: No outdoor work areas are proposed for this site. SC-5 Protect Trash Storage Areas from Rainfall, Run-On, Runoff, and Wind Dispersal Yes 0 No 0 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). On-site storm drain inlets III Yes 0 No 0 N/A El Interior floor drains and elevator shaft sump pumps El Yes 0 No 0 N/A O Interior parking garages 0 Yes 0 No 0 N/A M Need for future indoor & structural pest control 0 Yes 0 No 0 N/A El Landscape/Outdoor Pesticide Use 0 Yes 0 No El N/A El Pools, spas, ponds, decorative fountains, and other water features 0 Yes I El No El N/A 0 Food service 0 Yes 0 No 0 N/A El Refuse areas 0 Yes 0 No 0 N/A El Industrial processes 0 Yes El No 0 N/A F] Outdoor storage of equipment or materials El Yes El No 0 N/A El Vehicle and Equipment Cleaning 0 Yes 0 No Ill N/A El Vehicle/Equipment Repair and Maintenance 0 Yes 0 No 0 N/A Fuel Dispensing Areas El Yes El No 0 N/A El Loading Docks 0 Yes El No 0 N/A C] Fire Sprinkler Test Water 0 Yes El No 0 N/A Miscellaneous Drain or Wash Water 0 Yes 0 No El N/A El Plazas, sidewalks, and parking lots 0 Yes 0 No 1 0 N/A For "Yes" answers, identify the additional BMP per Appendix E.I. Provide justification for No" answers. Storm Drain Inlets: Provide storm water pollution prevention information Indoor & Outdoor Pesticide use: Provide Integrated Pest Management information Pools & Spas: Provide sanitary sewer cleanout per City of Carlsbad regulations Miscellaneous Drain Water: No copper or unprotected metals on roof I I E-36 Page 2 of 4 Revised 09/16 Li I I I I I I FJ I I Li I [11 I E-36 Page 3 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 Applied? SD-1 Maintain Natural Drainage Pathways and Hydrologic Features III Yes 0 No El N/A Discussion/justification if SD-1 not implemented: SD-2 Conserve Natural Areas, Soils, and Vegetation lii Yes 0 No 0 N/A Discussion/justification if SD-2 not implemented: SD-3 Minimize Impervious Area I li Yes I 0 No I 0 N/A Discussion/justification if SD-3 not implemented: SD-4 Minimize Soil Compaction I iii Yes 0 No El N/A Discussion/justification if SD-4 not implemented: SD-5 Impervious Area Dispersion I iii Yes 1-0 No 1 0 N/A Discussion/justification if SD-5 not implemented: I Li I I I Fi Li -j Li I I I I I I I I I I Site Design Requirement (continued) Applied? SD-6 Runoff Collection 9Yes 0 No 0 N/A Discussion/justification if SD-6 not implemented: SD-7 Landscaping with Native or Drought Tolerant Species N Yes 0 No Discussion/justification if SD-7 not implemented: SD-8 Harvesting and Using Precipitation I 0 Yes 0 No I N N/A Discussion/justification if SD-8 not implemented: The site area is too small to implement harvesting in a cost effective manner. See form 1-7 in attachments. I I I I I I I I I I E-36 Page 4 of 4 Revised 09/16 I I I I [1 LI I I SUMMARY OF PDP STRUCTURAL BMPS I 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 I 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). I 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 I Design Manual). Use this form to provide narrative description of the general strategy for structural BMP I 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 I 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 I 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. [Continue on next page as necessary.] Runoff from the proposed roof and hardscape will be diverted to various planters around the residence. These planters will be built to function as biofiltration basins, and runoff from all the biofiltration basins will be collected in a vault under the lower level patio. An outlet structure built into the vault will provide proper hydromodification and flood control of the treated waters. Output from the vault will be routed to a slotted PVC pipe laid level and surrounded by gravel to mimic sheet flow. Treated flow from the developed area will comingle with the wetland buffer area flow prior to flowing into the Agua Hedionda Lagoon. I I I I I I I 1 I 1 I I I I I I I I I I I I I I Chapter 5: Storm Water Pollutant Control Requirements for PDPs Step 18: Adjust runoff factor to Step 1: Evaluate at account for site design BMPs DMA Scale and estimate DCV Refer to Section 5.3, 8.1 & B.2 Step 1A: Is the DMA "Self- mitigating" or "Dc minimis" or No "Self-retaining"? Refer to Section 5.2 Step 2: Is Harvest Yes and Use Feasible? Refer to Section 5.4.1 Step 2A: Implement Harvest and use BMPs* Refer to Section 5.5.1.1 Step 28: Is DC retained? No Refer to Appendix 8.3 See Figure 5-2 Yes Compliant with Pollutant Control BMP Sizing Requirements Steps 6 & 7: Prepare O&M requirements and Storm Water Quality Management Plan - Refer to Chapters 7 and 8 * Step 2C: Project applicant has an option to also conduct feasibility analysis for infiltration and if infiltration is fully or partially feasible has an option to choose between infiltration and harvest and use BMPs. But if infiltration is not feasible and harvest and use Is feasible, project applicant must implement harvest and use BMPs FIGURE 5-1. Storm Water Pollutant Control BMP Selection Flow Chart 5-2 February 2016 Step 3A&0: Full Infiltration Condition Refer to Section 5.5.1.2 Step 3A&8: Partial step 3A&8: No Infiltration Infiltration Condition Condition Refer to Section Refer to Section 5.5.2 5.5.3 Step 3C Compute Step 3C: compute Step 3C: Compute Sizing Requirements Sizing Requirements Sizing Requirements Refer to Appendix 8.4 Refer to Appendix 8.5 Refer to Appendix 9.5 I I I I I I I I I I I I I 1 I I I I I Chapter 5: Storm Water Pollutant Control Requirements for PDPs Step 3: Is Infiltration Feasible? Refer to Section \. S.4.2 .d Step 40: Implement OMP using maximum feasible footprint and document why the remaining BMP size could not fit on site* Refer to Appendix 8.5 and £ Compi iant with Pollutant Control BMP Sizing Requirements Steps 6 & 7: Prepare O&M requirements and Storm Water Quality Management Plan - Refer to Chapters land S * Project approval at the discretion of (City Engineer) FIGURE 5-2. Storm Water Pollutant Control BMP Selection Flow Chart 5-3 February 2016 Step 4: Can the No BMP be designedior the remaining DCV? Step 5: implement Flow- thru Treatment Control AND 8MPs Refer to Section 5.5.4 and Appendix 8.6 Step 5A: Participate in Alternative Compliance Program Refer to Section 1,8 Step 4A: Design BMP for the required size, per design criteria and considerations listed in the fact sheets Refer to Appendix E Structural BMP Summary Information [Copy this page as needed to provide information for each individual proposed structural BMP] Structural BMP ID No. IMP I DWG Sheet No. 3 Type of structural BMP: E Retention by harvest and use (HU-1) E Retention by infiltration basin (INF-1) 1 Retention by bioretention (INF-2) 0 Retention by permeable pavement (lNF-3) Partial retention by biofiltration with partial retention (PR-1) Biofiltration (BF-1) o 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) ii Detention pond or vault for hydromodification management El Other (describe in discussion section below) Purpose: Pollutant control only O Hydromodification control only O Combined pollutant control and hydromodification control El Pre-treatment/forebay for another structural BMP 0 Other (describe in discussion section below) Discussion (as needed): I 1 1 I I I I I I I I I I LI r L I I I I Structural BMP Summary Information [Copy this page as needed to provide information for each individual proposed structural BMP] Structural BMP ID No. IMP 2 DWG Sheet No. 3 Type of structural BMP: El Retention by harvest and use (HU-l) Li Retention by infiltration basin (INF-I) El Retention by bioretention (INF-2) El Retention by permeable pavement (lNF-3) El Partial retention by biofiltration with partial retention (PR-1) Biofiltration (BF-1) Li 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) El Detention pond or vault for hydromodification management El Other (describe in discussion section below) Purpose: Pollutant control only El Hydromodification control only U Combined pollutant control and hydromodification control El Pre-treatment/forebay for another structural BMP El Other (describe in discussion section below) Discussion (as needed): I 1 fl I I [1 Li I 1 I I I Li H I I I I I Structural BMP Summary Information [Copy this page as needed to provide information for each individual proposed structural BMP] Structural BMP ID No. IMP 3 DWG Sheet No. 4 Type of structural BMP- 11 Retention by harvest and use (HU-1) Retention by infiltration basin (lNF-l) Li Retention by bioretention (INF-2) Li Retention by permeable pavement (INF-3) Li Partial retention by biofiltration with partial retention (PR-1) Biofiltration (BF-1) U 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) U Detention pond or vault for hydromodification management U Other (describe in discussion section below) Purpose: Pollutant control only Li Hyd romod ifi cation control only D Combined pollutant control and hydromodification control U Pre-treatment/forebay for another structural BMP U Other (describe in discussion section below) Discussion (as needed): Li TT H I r I I 1 I I I I L I I I 1 I Structural BMP Summary Information [Copy this page as needed to provide information for each individual proposed structural BMP] Structural BMP ID No. IMP 4 DWG Sheet No. 3 Type of structural BMP: Retention by harvest and use (HU-l) Retention by infiltration basin (INF-l) 0 Retention by bioretention (INF-2) 0 Retention by permeable pavement (lNF-3) 0 Partial retention by biofiltration with partial retention (PR-1) Biofiltration (BF-1) U 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) U Detention pond or vault for hydromodification management O Other (describe in discussion section below) Purpose: Pollutant control only O Hydromodification control only Combined pollutant control and hydromodification control Pre-treatment/forebay for another structural BMP 0 Other (describe in discussion section below) Discussion (as needed): I 1 I I Li I I LI I I I Li I I I I I I I L Structural BMP Summary Information [Copy this page as needed to provide information for each individual proposed structural BMP] Structural BMP ID No. IMP 5 DWG Sheet No. 4 Type of structural BMP: Retention by harvest and use (HU-1) E Retention by infiltration basin (INF-1) fl Retention by bioretention (lNF-2) O Retention by permeable pavement (lNF-3) 0 Partial retention by biofiltration with partial retention (PR-1) Biofiltration (BF-1) o 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) 0 Detention pond or vault for hydromodification management Li Other (describe in discussion section below) Purpose: Pollutant control only LI Hydromodification control only LI Combined pollutant control and hydromodification control El Pre-treatment/forebay for another structural BMP El Other (describe in discussion section below) Discussion (as needed): 11 1 1 I I I I d I I 1 I I I I I Structural BMP Summary Information [Copy this page as needed to provide information for each individual proposed structural BMP] Structural BMP ID No. IMP 6 DWG Sheet No. 4 Type of structural BMP: El Retention by harvest and use (HU-1) El Retention by infiltration basin (INF-1) El Retention by bioretention (INF-2) El Retention by permeable pavement (INF-3) o Partial retention by biofiltration with partial retention (PR-1) O Biofiltration (BF-1) El 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 El Other (describe in discussion section below) Purpose: El Pollutant control only Hydromodification control only El Combined pollutant control and hydromodification control El Pre-treatment/forebay for another structural BMP El Other (describe in discussion section below) Discussion (as needed): See SWMMM Modeling Memorandum dated March 1, 2017 from Tory R. Walker Engineering for sizing and hydromodification calculations (included as a separate attachment) See Vector Control Plan Memorandum dated May 2, 2017 from Tory R. Walker Engineering (included as a separate attachment) II Ii I I I I I I I I I I Li I I ATTACHMENT I BACKUP FOR PDP POLLUTANT CONTROL BMPS I This is the cover sheet for Attachment 1. Check which Items are Included behind this cover sheet: Attachment Contents Checklist Sequence Attachment 1 DMA Exhibit (Required) See DMA Included Exhibit Checklist on the back of this Attachment cover sheet. (24"x36" Exhibit typically required) Attachment lb Tabular Summary of DMAs Showing Included on DMA Exhibit in DMA ID matching DMA Exhibit, DMA Attachment la Area, and DMA Type (Required)* Included as Attachment I b, *Provide table in this Attachment OR separate from DMA Exhibit on DMA Exhibit in Attachment la Attachment 1 Form 1-7, Harvest and Use Feasibility n Included Screening Checklist (Required unless D Not included because the entire the entire project will use infiltration project will use infiltration BMPs BMPs) Refer to Appendix B.3-1 of the BMP Design Manual to complete Form 1-7. Attachment Id Form 1-5, Categorization of Infiltration Included Feasibility Condition (Required unless LI Not included because the entire the project will use harvest and use project will use harvest and use BMPs) Refer to Appendices C and D of BMPs the BMP Design Manual to complete Form 1-8 (referred to as 1-8 in the manual). Attachment le Pollutant Control BMP Design Included Worksheets I Calculations (Required) Refer to Appendices B and E of the BMP Design Manual for structural pollutant control BMP design guidelines I I I I I I I I Li [j 1 I I I LI I I I ATFACHMENT la U U I I I I I I I I I I I I I I I DMA EXHIBI T SCALE: 1"-10' IMP 4 1 I m BIORL MA liON BASIN 44 SF DMA NOTES: SITE IS HYDROLOGIC GROUP 'B' APPROXIMATE DEPTH TO GROUNDWATER IS 25 FEET. DMA EXHIBIT JOB Na 13-036 5/02/17 SOWARDS & BROWN ENGINEERING CONSULTING ENGINEERS 2187 NEWCASTLE AVENUE SUITE 103 CARDIFF BY THE SEA, CA, 92007 TEL 760/436-8500 FAX 760/436-8603 I ATTACHMENT lc II I I I I Ll I TI I I I I I I i I I Appendix I: Forms and Checklists IKb e!ix1 an MRnAftammm Is there a demand for harvested water (check all that apply) at the project site that is reliably present during the wet season? CQ Toilet and urinal flushing O Landscape irrigation 0 Other:______________ 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. [Provide a summary of calculations here] X x( J; den II CF Calculate the DCV using worksheet B.2-l. DCV = 71 2. (cubic feet) 3a. Is the 36 hour demand greater 3b. Is the 36 hour demand greater than 3c. Is the 36 hour demand than or equal to the DCV? 0.25DCV but less than the full DCV? less than 0.25DCV? O Yes / No E 0 Yes / No K Yes Harvest and use appears to be Harvest and use may be feasible. Harvest and use is feasible. Conduct more detailed Conduct more detailed evaluation and considered to be infeasible. evaluation and sizing calculations sizing calculations to determine to confirm that DCV can be used feasibility. Harvest and use may only be at an adequate rate to meet able to be used for a portion of the site, drawdown criteria, or (optionally) the storage may need to be upsized to meet long term capture targets while draining in longer than 36 hours. Is harvest and use feasible based on further evaluation? 0 Yes, refer to Appendix E to select and size harvest and use BMPs. No, select alternate BMPs. I I 1 1-2 February 2016 I Ii I I I I I I [TI I I I I I I I I ATTACHMENT id I I I I I I R I I I I I 1 I I I I I I I I 1 1 I I I, I I I I JOB # 16-190-S Storm Water BMP 08/16/16 Test Site Location: Percolation Data 4400 Block of Adams Street, Carlsbad Infiltration BMP Type Infiltration Basin Test Method Shallow Percolation Testing (Option 2) Factor of Safety FS3 Drill Date 08/08/16 Test Date 08/09/16 Equipment Type Skid Steer Using Solid Stem Auger Test Bore Diameter 8" inch Observation Bore Diameter 8" inch Groundwater Conditions Groundwater NOT Encountered Shore Line is 25' Vertical Elevation Below Proposed SWQC Basins Weather Conditions Dry, Sunny, 880 to 90° F 2 3 4 3' 3' 3' 15.00 2.22 1.07 0.36 BAISN #1 2.04 4.80 5 3' 40.00 0.10 6 3' 30.00 0.17 BASIN #2 7 3' 30.00 0.13 8 3' 30.00 0.15 BAISN #1 Average= 4.81 mpi Average = 3.58 in/hr BASIN #2 Average = 32.50 mpi Average = 0.14 in/hr Infiltration Rates Vary Slightly Due to Actual Depth of Hole In Inches Depth (ft) I Ober'ation.oring A 08/8/2016 0 - 3' Tan Loamy Sand 3-10' Tan Sandy Clay End © 10' U - Ian Loamy San 3 - 10' Tan Sandy Clay r....J USCS Soil Classifications 2450 Auto Park Way \Jinje & Middleton Escondido, CA 92029-1229 Engineering, Inc. (760) 743-1214 VINJE & WDDLETON ENGINEERING, INC. 2450 Auto Park Way Escondido, CA 92029-122 760- 74311Th,.. /- c-I / 4) BASIN #1 AREA Fa N31M3EZ6Ob I T111 IF / / ® © f•7L&/7 •7/ I OW$EWEI. I 1 __-- E3T10 PA FB -_/ BASIN # LLL t3 Ij 4 SITE PLAN DATE. _8/18/2016 JOB No. 18-190—S APN 206-200-03 ACRES 0.48 OwnersAddress SiteLocation Neil Martin Adams Street, 1878 Shadetree Drive, Carlsbad San Marcos, CA 92078 858-6514018 nei1rnqua1comm,com LEGEND Perc Test Location -_Groundwater Boring 30_—.....Contour Line w/ 1' Interval FIGURE1 Infiltration Test. Boring Location Map I 16-190-S BASIN #1 RESULTS PAGE - -Affil trattonFésibth Scre Cna I2 I______ Is the estimated reliable infiltration rate below proposed facility locations greater than 0.5 inches per hour? The 1 response to this Screening Question shall be based on a X comprehensive evaluation of the factors presented in Appendix C.2 and Appendix D. Provide-basis: TEST DATA WAS COLLECTED FROM FOUR 8" INCH DIAMETER BORINGS DRILLED TO 3' FEET AND ONE 8" INCH BORING DRILLED TO 10' FEET WITHIN THE RESIDENTIAL STORM WATER DETENTION BASIN #1 AREA. SEE ATTACHED INFILTRATION RATE RESULTS. MAXIMUM INFILTRATION RATES OF = 7.10 INCHES/HOUR AND MINIMUM INFILTRATION RATE = 0.36 INCHES/HOUR WERE RECORDED. AVERAGED TESTED INFILTRATION RATES = 3.58 IN/HR. Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative discussion of study/data source applicability. 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: INFILTRATION BASIN #1 IS IMMIEDATLEY ADJACENT TO THE PROPOSED STRUCTURE FOUNDATIONS AND COULD VERY WELL CAUSE DAMGAE FROM INJECTED STORM WATER. INFILTRATION BASINS ARE ALSO PROPOSED WITHIN CLOSE PROXIMITY TO A MAJOR EXISTING SEWER LINE. THIS UTILITY MUST BE PROTECTED FROM POTENTIAL DAMAGE CAUSED BY THE PROPOSED SUBSURFACE BASIN DISCHARGE. IF DAMAGED THIS COULD CAUSE RAW SEWAGE TO FLOW INTO A PROTECTED . BODY OF WATER, NAMLEY THE HEDIONDA LAGOON. Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative discussion of study/data source applicability. I' Template Date: March 29, 2016 Preparation Date: 12/07/16 POP SWQMF - Attachments I I I] I I] I 1 I I I I I Can infiltration greater than 0.5 inches per hour be allowed without increasing risk of groundwater contamination 3 (shallow water table, storm water pollutants or other factors) X 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: THE PROPOSED RESIDENTIAL STORM WATER INFILTRATION BASINS WILL HAVE A MINIMUM OF 10' FEET VERTICAL SEPARATION FROM BASIN BOTTOM TO ESTIMATED GROUNDWATER ELEVATION. STABALIZED GROUNDWATER CONDIDTIONS ARE EXPECTED AT APPROXIMATLEY 25' FEET BELOW EXISTING GRADE AT BORINGS A AND B. PROPOSED BASIN DEPTH BOTTOM IS 3' FEET BELOW EXISTING GRADE. Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative discussion of study/data source applicability. Can infiltration greater than 0.5 inches per hour be allowed without causing potential water balance issues such as change 4 of seasonally or ephemeral streams or increased discharge of X contaminated groundwater to surface waters? The response to this Screening Question shall he based on a comprehensive evaluation of the factors presented in Appendix C.3. Provide basis: RESIDENTIAL STORM WATER BASIN INFILTRATION WILL NOT OCCUR WITHIN APPROXIMATLEY 80' FEET OF AGUA HEDIONDA LAGOON HIGH TIDE LINE. CONTAMINATED WATER WILL NOT BE DISCHARGED DIRECTLEY TO THE GROUND SURFACE. Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative discussion of study/data source applicability. If all answers to rows I - 4 are "Yes" a full infiltration design is potentially feasible. The feasibility screening category is Full Infiltration PULL Part 1 INFILTRATION? Result* If any answer from row 1-4 is "No", infiltration may be possible to some extent but NO would not generally be feasible or desirable to achieve a "full infiltration" design. Proceed to Part 2 Template Date: March 29, 2016 Preparation Date: 12/07/16 PDP SWQMP . Attachments El l I KNO I, P, ROVElasm-- t, I Scree. N. t , tion It IN z up- Do soil and geologic conditions allow for infiltration in any 5 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: TEST DATA WAS COLLECTED FROM FOUR 8" INCH DIAMETER BORINGS DRILLED TO 3' FEET AND ONE 8" INCH BORING DRILLED TO 10' FEET WITHIN THE RESIDENTIAL STORM WATER DETENTION BASIN #1 AREA. SEE ATTACHED INFILTRATION RATE RESULTS. MAXIMUM INFILTRATION RATES OF = 7.10 INCHES/HOUR AND MINIMUM INFILTRATION RATE = 0.36 INCHES/HOUR WERE RECORDED. AVERAGED TESTED INFILTRATION RATES = 3.58 IN/HR. 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. Can Infiltration in any appreciable quantity be allowed without increasing risk of geotechnical hazards (slope stability, 6 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: INFILTRATION BASINS ARE PROPOSED WITHIN CLOSE PROXIMITY TO A MAJOR EXISTING SEWER LINE. THIS UTILITY MUST BE PROTECTED FROM DAMAGE. AS DAMAGE TO THE SEWER LINE WOULD CAUSE A MAJOR ENVIRONMENTAL PROBLEM TO THE NEAR BY HEDIONDA LAGOON. STRUCTURAL INTEGRITIY OF THE PROPOSED RESIDENCE WOULD LIKEY RESULT AS WELL. BASED ON POTENTIAL STRUCTURAL CONCERNS TO THE PROPOSED RESIDENCE AND THE EXISTING UTILITIES IT IS MY PROFESSIONAL OPINION THAT INFILTRATION SHOULD NOT BE ALLOWED ON THIS SITE 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. I Template Date: March 29, 2016 Preparation Date: 12/07/16 POP SWQ111P Attachments I I I I I 1 I I LF I I U 0 Not IBM In NO- lum 111 Can Infiltration in any appreciable quantity be allowed without posing significant risk for groundwater related concerns x (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: THE PROPOSED RESIDENTIAL STORM WATER INFILTRATION BASINS WILL HAVE A MINIMUM OF 10' FEET VERTICAL SEPARATION FROM BASIN BOTTOM TO ESTIMATED GROUNDWATER ELEVATION. GROUNDWATER ELEVATION IS NOT EXPECTED TO VARY SIGNIFICANTLEY. STABALIZED GROUNDWATER CONDIDTIONS ARE ESTIMATED AT 25' FEET BELOW EXISTING GRADE IN BORINGS A AND B. PROPOSED BASIN DEPTH IS3' FEET BELOW EXISTING GRADE. 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. Can infiltration be allowed without violating downstream 8 water rights? The response to this Screening Question shall be X based on a comprehensive evaluation of the factors presented in Appendix C.3. Provide basis: DOWNSTREAM WATER RIGHTS VIOLATIONS ARE EXPECTED TO REMAIN UNCHANGED AND NON-EXISTING. 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. If all answers from row 5-8 are yes then partial infiltration design is potentially feasible. The feasibility screening category is Partial Infiltration. Part 2 NO Result* 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 Infiltration. I Template Date: March 29, 2016 Preparation Date: 12/07/16 PDP SWQMP - Attachments I I I I I I I I I The Geotechnical Engineer certifies they completed Form 1-5 except Criteria 4 & 8 (see Appendix C.4.3). Professional Geotechnical Engineer's Printed Name: [SEAL] I I I I I I I Template Date: March 29, 2016 Preparation Date: 12/07/16 PDP SWQMP - Attachments I I 16-190-S BASIN #2 RESULTS PAGE from a iio (rnten es 16 Fig Is the estimated reliable infiltration rate below proposed facility locations greater than 0.5 inches per hour? The response I to this Screening Question shall be based on a comprehensive X evaluation of the factors presented in Appendix C.2 and Appendix D. Provide basis: TEST DATA WAS COLLECTED FROM FOUR 8" INCH DIAMETER BORINGS DRILLED TO 3' FEET AND ONE 8" INCH BORING DRILLED TO 10' FEET WITHIN THE RESIDENTIAL STORM WATER DETENTION BASIN #2 AREA. SEE ATTACHED INFILTRATION RATE RESULTS. MAXIMUM INFILTRATION RATES OF = 0.17 INCHES/HOUR AND MINIMUM INFILTRATION RATE = 0.10 INCHES/HOUR WERE RECORDED. AVERAGED TESTED INFILTRATION RATES = 0.14 IN/HR. Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative discussion of study/data source applicability. 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 X - 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: INFILTRATION BASIN #2 IS IMMIEDATLEY ADJACENT TO THE PROPOSED STRUCTURE FOUNDATIONS AND COULD VERY WELL CAUSE DAMGAE FROM INJECTED STORM WATER. INFILTRATION BASINS ARE ALSO PROPOSED WITHIN CLOSE PROXIMITY TO A MAJOR EXISTING SEWER LINE. THIS UTILITY MUST BE PROTECTED FROM POTENTIAL DAMAGE CAUSED BY THE PROPOSED SUBSURFACE BASIN DISCHARGE. IF DAMAGED THIS COULD CAUSE RAW SEWAGE TO FLOW INTO A PROTECTED BODY OF WATER, NAMLEY THE HEDIONDA LAGOON. Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative discussion of study/data source applicability. Template Date: March 29, 2016 Preparation Date: 12/07/16 PDP SWQMP - Attachments I Can infiltration greater than 0.5 inches per hour be allowed without increasing risk of groundwater contamination (shallow 3 water table, storm water pollutants or other factors) that cannot X 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: AVERAGED TESTED INFILTRATION RATES = 0.14 IN/HR. THE PROPOSED RESIDENTIAL STORM WATER INFILTRATION BASINS WILL HAVE A MINIMUM OF 10' FEET VERTICAL SEPARATION FROM BASIN BOTTOM TO ESTIMATED GROUNDWATER ELEVATION. STABALIZED GROUNDWATER CONDIDTIONS ARE EXPECTED AT APPROXIMATLEY 25' FEET BELOW EXISTING GRADE AT BORINGS A AND B. PROPOSED BASIN DEPTH BOTTOM IS3' FEET BELOW EXISTING GRADE. Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative discussion of study/data source applicability. Can infiltration greater than 0.5 inches per hour be allowed without causing potential water balance issues such as change 4 of seasonally or ephemeral streams or increased discharge of X 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: AVERAGED TESTED INFILTRATION RATES = 0.14 IN/HR. RESIDENTIAL STORM WATER BASIN INFILTRATION WILL NOT OCCUR WITHIN APPROXIMATLEY 80' FEET OF AGUA HEDIONDA LAGOON HIGH TIDE LINE. CONTAMINATED WATER WILL NOT BE DISCHARGED DIRECTLEY TO THE GROUND SURFACE. Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative discussion of study/data source applicability. If all answers to rows I - 4 are "Yes" a full infiltration design is potentially feasible. The feasibility screening category is Full Infiltration FULL Part 1 INFILTRATION? Result* If any answer from row 1-4 is "No", infiltration may be possible to some extent but NO would not generally be feasible or desirable to achieve a "full infiltration" design. Proceed to Part 2 I I Template Date: March 29, 2016 Preparation Date: 12/07/16 PDP SWQMP - Attachments I I I I I I I I RRIPER wo mpmgg 0. V-1 qt _ NICE Mt A M--11 0-11 Do soil and geologic conditions allow for infiltration in any 5 appreciable rate or volume? The response to this Screening x Question shall be based on a comprehensive evaluation of the factors presented in Appendix C.2 and Appendix D. Provide basis: TEST DATA WAS COLLECTED FROM FOUR 8" INCH DIAMETER BORINGS DRILLED TO 3' FEET AND ONE 8" INCH BORING DRILLED TO 10' FEET WITHIN THE RESIDENTIAL STORM WATER DETENTION BASIN #2 AREA. SEE ATTACHED INFILTRATION RATE RESULTS. MAXIMUM INFILTRATION RATES OF = 0.17 INCHES/HOUR AND MINIMUM INFILTRATION RATE. = 0.10 INCHES/HOUR WERE RECORDED. AVERAGED TESTED INFILTRATION RATES = 0.14 IN/HR. 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. Can Infiltration in any appreciable quantity be allowed without increasing risk of geotechnical hazards (slope stability, 6 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: INFILTRATION BASINS ARE PROPOSED WITHIN CLOSE PROXIMITY TO A MAJOR EXISTING SEWER LINE. THIS UTILITY MUST BE PROTECTED FROM DAMAGE POTENTIALLY CAUSED BY THE PROPOSED SUBSURFACE BASIN DISCHARGE, WHICH COULD CAUSE RAW SEWAGE FLOW INTO A PROTECTED BODY OF WATER, NAMLEY THE HEDIONDA LAGOON. 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. I I Template Date: March 29, 2016 Preparation Date: 12/07/16 POP SWQMP - Attachments I F I I F' I I I If" RARK MINE Can Infiltration in any appreciable quantity be allowed without posing significant risk for groundwater related concerns x (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: THE PROPOSED RESIDENTIAL STORM WATER INFILTRATION BASINS WILL HAVE A MINIMUM OF 10' FEET VERTICAL SEPARATION FROM BASIN BOTTOM TO ESTIMATED GROUNDWATER ELEVATION. GROUNDWATER ELEVATION IS NOT EXPECTED TO VARY SIGNIFICANTLEY. STABALIZED GROUNDWATER CONDIDTIONS ARE ESTIMATED AT 25' FEET BELOW EXISTING GRADE IN BORINGS A AND B. PROPOSED BASIN DEPTH IS 3' FEET BELOW EXISTING GRADE. 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: DOWNSTREAM WATER RIGHTS VIOLATIONS ARE EXPECTED TO REMAIN UNCHANGED AND NON-EXISTING. 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. If all answers from row 5-8 are yes then partial infiltration design is potentially feasible. NO Part 2 The feasibility screening category is Partial Infiltration. Result* If any answer from row 5-8 is no, then infiltration of any volume is considered to be PARTIAL infeasible within the drainage area. The feasibility screening category is No Infiltration. INFILTRATION Ll 1 Template Date: March 29, 2016 Preparation Date: 12/07/16 PDP SWQMP - Attachments I El I I n Li I I I . I I I I I I I I I I I I I I I I I I Template Date: March 29, 2016 Preparation Date: 12/07/16 PDP SWQMP - Attachments Date: ProfessiojrGechnicaI Enqei'Siqned jsJame: Professional Geotechnical Engineer's Printed Name: RALPH MALCOLM VINJE The Geotechnical Engineer certifies they completed Form 1-5 except Criteria 4 & 8 (see Appendix C.4.3). [SEAL] I I ATTACHMENT le I I I I I I I I I I LI I I I 1 I I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods Worksheet B.2-1. DCV 85h percentile 24-hr storm depth from Figure B.l-1 d= 0 . 6 inches 2 Area tributary to BMP (s) A= 0. acres 3 Area weighted runoff factor (estimate using Appendix B.l.l and B.2.1) unitless 4 Tree wells volume reduction TCV= cubic-feet 5 Rain barrels volume reduction RCV= 0 cubic-feet 6 Calculate DCV = (3630 x C x d x A) - TCV -RCV DCV= ? 2 cubic-feet I I [I I Li I I I 1 I B-b February 2016 [1 I I I I I I I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods Worksheet B.2-1. DCV IMP I 1 85t1 percentile 24-hr storm depth from Figure B.1-1 d= 0.60 inches 2 Area tributary to BMP (s) A= 0.014 acres 3 Area weighted runoff factor (estimate using Appendix B.1.1 and B.2.1) C= 0.90 umtless 4 Tree wells volume reduction TCV= 0 cubic-feet 5 Rain barrels volume reduction RCV cubic-feet 6 Calculate DCV = 1 (3630 x C x d x A) - TCV - RCV DCV= 27 cubic-feet I I I I I E1 II I B-10 February 2016 I I I I I I I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods Worksheet B.5-1: Simple Sizing Method for Biofiltration BMPs I M P 1 1 1 Remaining DCV after implementing retention BMPs 27 cubic-feet Partial Retention 2 Infiltration rate from Form 1-9 if partial infiltration is feasible 0 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] 0 inches 5 Aggregate pore space 0.40 in/in 6 Required depth of gravel below the underdrain [Line 4/ Line 5] 0 inches 7 Assumed surface area of the biofiltration BMP 44 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 8 cubic-feet 10 DCV that requires biofiltration [Line I - Line 9] 19 cubic-feet BMP Parameters ii Surface Ponding [6 inch minimum, 12 inch maximum] 6 inches 12 - Media Thickness [18 inches minimum] ' also add mulch layer thickness to this line for sizing calculations 21 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 6 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; f the filtration is controlled by the outlet, use the outlet controlled rate) i .ti 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 [Line 11 + (Line 12 x Line 14) + (Line 13 x Line 5)] inches 19 Total Depth Treated [Line 17 + Line 18] 42.6 inches Op ion 1— Biofilter 1.5 times the DCV 20 Required biofiltered volume [1.5 x Line 10] 29 cubic-feet 21 Required Footprint [Line 20/ Line 19] x 12 8 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] 14 cubic-feet 23 Required Footprint [Line 22/ Line 18] x 12 13 sq-ft Footprint of the BMP 24 1 Area draining to the BMP 616 sq-ft 25 Adjusted Runoff Factor for drainage area (Refer to Appendix B.1 and B.2) 0.90 26 Minimum BMP Footprint [Line 24 x Line 25 x 0.03] 17 sq-ft 27 Footprint of the BMP = Maximum(Minimum(Line 21, Line 23), Line 26) 17 sq-ft Note: Line 7 is used to estimate the amount ot volume retained oy tue J1vir. upuate assumeu surrace area in Janc i uuui its equivalent to the required biofiltration footprint (either Line 21 or Line 23) I I 1 I I LI I I 1 I I I I I B-26 February 2016 I I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods Worksheet B.2-1. DCV I M P 2 85 percentile 24-hr storm depth from Figure B.1-1 d= 0.60 inches 2 Area tributary to BMP (s) A= 0.012 acres 3 Area weighted runoff factor (estimate using Appendix B.l.1 and B.2. 1) C= 0.90 unitless 4 Tree wells volume reduction TCV= 0 cubic-feet 5 Rain barrels volume reduction RCV 0 cubic-feet 6 Calculate DCV = (3630 x C x d x A) - TCV -RCV DCV= 24 cubic-feet I I 1 iii I I I I Iii I I B-10 February 2016 I I 11 I I III I I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods Worksheet B.5-1: Simple Sizing Method for Biofiltration BMPs I M P 2 1 j Remaining DCV after implementing retention BIvIPs 24 cubic-feet Partial Retention 2 Infiltration rate from Form 1-9 if partial infiltration is feasible 0 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] 0 inches 5 Aggregate pore space 0.40 in/in 6 Required depth of gravel below the underdrain [Line 4/ Line 5] 0 inches 7 Assumed surface area of the biofiltration BMP 21 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 4 cubic-feet 10 1 DCV that requires biofiltration [Line I - Line 9] 20 cubic-feet BMP Parameters 11 Surface Ponding [6 inch minimum, 12 inch maximum] 6 inches 12 - Media Thickness [18 inches minimum] also add mulch layer thickness to . this line for sizing calculations 21 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 6 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)] 12.6 inches 19 Total Depth Treated [Line 17 + Line 18] 42.6 inches OP ion 1— Biofilter 1.5 times the DCV 20 Required biofiltered volume [1.5 x Line 101 30 cubic-feet 21 Required Footprint [Line 20/ Line 19] x 12 8 sq-ft OP 'on 2- Store 0.75 of remaining DCV in pores and ponding 22 Required Storage (surface + pores) Volume [0.75 x Line 10] 15 cubic-feet 23 Required Footprint [Line 22/ Line 18] x 12 15 sq-ft Footprint of the BMP 24 Area draining to the BMP 535 sq-ft 25 Adjusted Runoff Factor for drainage area (Refer to Appendix B.1 and B.2) 0.90 26 Minimum BMP Footprint [Line 24 x Line 25 x 0.03] 14 sq-ft 27 Footprint of the BMP = Maximum(Minimum(Line 21, Line 23), Line 26) 14 Note: Line 7 is used to estimate the amount ot volume retained by Use I51VW. upuate assunieo surrace area in Ianc i uuui its equivalent to the required biofiltration footprint (either Line 21 or Line 23) I I 1 ii I I II] I I I [ II II I F] I B-26 February 2016 I ' Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods Worksheet B.2-1. DCV I M P 3 1 85 percentile 24-hr storm depth from Figure B.1-1 d= 0.60 inches 2 Area tributary to BMP (s) A= 0.034 acres 3 Area weighted runoff factor (estimate using Appendix B.1.1 and B.2.1) C= 0.86 unitless 4 Tree wells volume reduction TCV= 0 cubic-feet 5 Rain barrels volume reduction RCV 0 cubic-feet— 6 Calculate DCV = (3630 x C x d x A) - TCV - RCV DCV= 64 cubic-feet I I 1 I I I I I 1 I I B-10 February 2016 I I I I I I I I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods Worksheet B.5-1: Simple Sizing Method for Biofiltration BMPs I M P 3 1 Remaining DCV after implementing retention BMPs [ 64 cubic-feet Partial Retention 2 Infiltration rate from Form 1-9 if partial infiltration is feasible 0 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] 0 inches 5 Aggregate pore space 0.40 in/in 6 Required depth of gravel below the underdrain [Line 4/ Line 5] 0 inches 7 Assumed surface area of the biofiltration BMP 55 sq-ft 8 Media retained pore storage 0.1 in/in 9 Volume retained by BMP [[Line 4 + (Line 12 x Line 8)1/12] x Line 7 10 cubic-feet 10 DCV that requires biofiltration [Line 1 - Line 91 54 cubic-feet BMP Parameters 11 Surface Ponding [6 inch minimum, 12 inch maximum] 6 inches 12 - Media Thickness [18 inches minimum], also add mulch layer thickness to . this line for sizing calculations 21 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 6 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; f the filtration s controlled by the outlet, use the outlet controlled rate) i i 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 . . . . [Linelt+(Lme12x Line 14)+(Lirie13x Line 5)] 12.6 inches 19 Total Depth Treated [Line 17 + Line 18] 42.6 inches Option 1— Biofilter 1.5 times the DCV 20 Required biofiltered volume [1.5 x Line 10] 81 cubic-feet 21 Required Footprint [Line 20/ Line 19] x 12 23 sq-ft 2- Store 0.75 of remaining DCV in pores and ponding ..c!ption 22 Required Storage (surface + pores) Volume [0.75 x Line 10] 41 [:39 cubic-feet 23 Required Footprint [Line 22/ Line 18] x 12 sq-ft Footprint of the BMP 24 Area draining to the BIVfP 1,483 sq-ft 25 Adjusted Runoff Factor for drainage area (Refer to Appendix B.1 and B.2) 0.86 26 Minimum BUT Footprint [Line 24 x Line 25 x 0.03] 38 sq-ft 27 Footprint of the BM? = Maximum(Minimum(Line 21, Line 23), Line 26) 35 - sq-ft Note: Line 7 is used to estimate the amount of volume retalnecl oy toe iDtvir. upuate asswneu su1Iac area iii j.wc i U- its equivalent to the required biofiltration footprint (either Line 21 or Line 23) I I I I I I I I 1 I [1 I I LI I I B-26 February 2016 I I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods Worksheet B.2-1. DCV I M P 4 85" percentile 24-hr storm depth from Figure B.1-1 d= 0.60 inches 2 Area tributary to BMP (s) A= 0.086 acres 3 Area weighted runoff factor (estimate using Appendix B.1.1 and B.2.1) C= 0.90 unitless 4 Tree wells volume reduction TCV= 0 cubic-feet 5 Rain barrels volume reduction RCV= cubic-feet 6 Calculate DCV (3630 x C x d x A) - TCV - RCV DCV= 169 cubic-feet I I S I I I I I I I I B-1O February 2016 II] I I II I I B-26 February 2016 I I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods Worksheet B.5-1: Simple Sizing Method for Biofiltration BMPs I M P 4 1 Remaining DCV after implementing retention BMPs 169 cubic-feet Partial Retention 2 Infiltration rate from Form 1-9 if partial infiltration is feasible 0 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] 0 inches 5 Aggregate pore space 0.40 in/in 6 Required depth of gravel below the underdrain [Line 4/ Line 5] 0 inches 7 Assumed surface area of the biofiltration BMP 126 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 22 cubic-feet 10 1 DCV that requires biofiltration [Line I - Line 9] 147 cubic-feet BMP Parameters 11 Surface Ponding [6 inch minimum, 12 inch maximum] 6 inches 12 - Media Thickness [18 inches minimum] also add mulch layer thickness to this line for sizing calculations 21 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 6 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 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 . [Linell± (Line 12x Line 14)+ (Line 13x Line 5)] 12.6 inches 19 Total Depth Treated [Line 17 + Line 18] 42.6 inches 1— Biofilter 1.5 times the DCV .c!ption 20 Required biofiltered volume [1.5 x Line 10] 221 cubic-feet 21 Required Footprint [Line 20/ Line 19] x 12 62 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] 110 cubic-feet 23 Required Footprint [Line 22/ Line 18] x 12 105 sq-ft Footprint of the BMP 24 1 Area draining to the BMP 3,732 sq-ft 25 Adjusted Runoff Factor for drainage area (Refer to Appendix B.1 and B.2) 0.90 26 Minimum BMP Footprint [Line 24 x Line 25 x 0.03] 101 sq-ft 27 Footprint of the BMP = Maximum(Minimum(Line 21, Line 23), Line 26) 101 sq-ft Note: Line 7 is used to estimate the amount ot volume retained toe nlvu-'. upaate assumeci suriace area in ine / unut its equivalent to the required biofikration footprint (either Line 21 or Line 23) F I I I I I 1 I I I I I I I I 1 I I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods Worksheet B.2-1. DCV I M P 5 I 85t percentile 24-hr storm depth from Figure B.1-1 d= 0.60 inches 2 Area tributary to BMP (s) A= 0.025 acres 3 Area weighted runoff factor (estimate using Appendix B.1.1 and B.2.1) C= 0.90 unitless 4 Tree wells volume reduction TCV= 0 cubic-feet 5 Rain barrels volume reduction RCV= 0 cubic-feet 6 Calculate DCV (3630 x C x d x A) - TCV - RCV DCV= 49 cubic-feet 1 I I r I L I I I I I B-10 February 2016 I I LII I I 1 I I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods Worksheet B.5-1: Simple Sizing Method for Biofiltration BMPs I M P 5 ssmu - 1 Remaining DCV after implementing retention BIVIPs I49 I cubic-feet Partial Retention 2 Infiltration rate from Form 1-9 if partial infiltration is feasible 0 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] 0 inches 5 Aggregate pore space 0.40 in/in 6 1 Required depth of gravel below the underdrain [Line 4/ Line 5] 0 inches 7 Assumed surface area of the biofiltration BMP 38 sq-ft 8 Media retained pore storage 0.1 in/in 9 Volume retained by BIvfP [[Line 4 + (Line 12 x Line 8)]/12] x Line 7 7 cubic-feet 10 DCV that requires biofiltration [Line 1 - Line 9] 42 cubic-feet BMP Parameters 11 Surface Ponding [6 inch minimum, 12 inch maximum] 6 inches 12 Media Thickness [18 inches minimum], also add mulch layer thickness to . this line for sizing calculations 21 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 6 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 s controlled by the outlet, use the outlet controlled rate) i 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 [Line 11 + (Line 12 xLrne 14) + (Line 13 xLine 5)] inches 19 Total Depth Treated [Line 17 + Line 18] 42.6 inches Option 1— Biofiher 1.5 times the DCV 20 Required biofiltered volume [1.5 x Line 10] 63 cubic-feet 21 Required Footprint [Line 20/ Line 19] x 12 18 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] 32 cubic-feet 23 Required Footprint [Line 22/ Line 18] x 12 30 sq-ft Footprint of the BMP 24 1 Area draining to the BMP 1,086 sq-ft 25 Adjusted Runoff Factor for drainage area (Refer to Appendix B.l and B.2) 0.90 26 Minimum BMP Footprint [Line 24 x Line 25 x 0.03] 29 sq-ft 27 Footprint of the BMP = Maximum(Minimum(Line 21, Line 23), Line 26) 29 sq-ft Note: Line 7 Is used to estimate the amount ot volume retainer! DY me nivu. upuare assumcu SU1IaL uca m L4UC / its equivalent to the required biofiltration footprint (either Line 21 or Line 23) I I I I I I I El I I I I I I I B-26 February 2016 I I ATTACHMENT 2 BACKUP FOR PDP HYDROMODIFICATION CONTROL MEASURES [This is the cover sheet for Attachment 2.1 Indicate which Items are Included behind this cover sheet: Attachment Contents Checklist Sequence Attachment 2a Hydromodification Management Included Exhibit (Required) See SWMMM Modeling Memorandum dated March 1, 2017 from Tory R. Walker Engineering for sizing and hydromodification calculations (included as a separate attachment) Attachment 2b Management of Critical Coarse Exhibit showing project drainage Sediment Yield Areas (WMAA Exhibit boundaries marked on WMAA Critical is required, additional analyses are Coarse Sediment Yield Area Map optional) (Required) See Section 6.2 of the BMP Design Optional analyses for Critical Coarse Manual. Sediment Yield Area Determination U 6.2.1 Verification of Geomorphic Landscape Units Onsite U 6.2.2 Downstream Systems Sensitivity to Coarse Sediment U 6.2.3 Optional Additional Analysis of Potential Critical Coarse Sediment Yield Areas Onsite Attachment 2c Geomorphic Assessment of Receiving Not performed Channels (Optional) U Included See Section 6.3.4 of the BMP Design Manual. Attachment 2d U Included See SWMMM Modeling Memorandum dated March 1, 2017 from Tory R. Walker Engineering for sizing and hydromodification calculations (included as a separate Flow Control Facility Design and attachment) Structural BMP Drawdown Calculations (Required) See Vector Control Plan Memorandum dated May 2, 2017 See Chapter 6 and Appendix G of the from Tory R. Walker Engineering BMP Design Manual (included as a separate attachment) I Ii I I I I I I I I Li I I I I I I I I ATFACHMENT 2a I I I I I I I I H I I I I P I I I HUP EXHIBIT SCALE. 17=10' I WA HMP NOTES: SITE IS HYDROLOGIC GROUP 'B' 2. APPROXIMA iF DEPTH To GROUND WA TER IS 25 FEET. SEE SWUM MODELING MEMORANDUM DATED NOVEMBER 30, 2016 BY TORY R. WALKER ENGINEERING FOR HYDROMODIFICA TJON CALCULA T1ONS HMP EXHIBIT JOB NO. 13-036 5/02/17 SOWARDS & BROWN ENGINEERING CONSULTING ENGINEERS 2187 NEWCASTLE AVENUE SUITE 103 CARDIFF BY THE SEA, CA. 92007 TEL. 760/436-8500 FAX 760/436-8603 - ........- -----. .----. .--------- - --. •- H .-.. .-. --. -.-..----. -- I I ATFACHMENT 2b I I n I I I I I I I I LI I LI I U I jj oe /* _ *!L TL!) * , LJk L ;j 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: 1 Attachment 3 must identify: Typical maintenance indicators and actions for proposed structural BMP(s) I based on Section 7.7 of the BMP Design Manual I Final Design level submittal: Attachment 3 must identify: 1 El 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 I to reflect actual proposed components of the structural BMP(s) El How to access the structural BMP(s) to inspect and perform maintenance El Features that are provided to facilitate inspection (e.g., observation ports, I cleanouts, silt posts, or other features that allow the inspector to view necessary components of the structural BMP and compare to maintenance thresholds) I El Manufacturer and part number for proprietary parts of structural BMP(s) when applicable El Maintenance thresholds for BMPs subject to siltation or heavy trash(e.g., silt I 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 I determine where the bottom of the BMP is. If required, posts or other markings shall be indicated and described on structural BMP plans.) El Recommended equipment to perform maintenance ' El When applicable, necessary special training or certification requirements for inspection and maintenance personnel such as confined space entry or hazardous waste management I I I I I BMP Maintenance Plan The structural BMP Maintenance Plan is in accordance with Category 1 requirements with I minimal maintenance responsibilities on a single family residential project. The property owner is responsible to ensure inspection, operation, and maintenance of the structural BMP. I Inspection of the biofiltration basins will be performed annually prior to the start of the rainy season. The biofiltration basins are accessible to the property owner. The inspection will include measuring the ground elevation is 6" below the opening or riser top elevation and I adjusting the grade as necessary to provide 6" of surface ponding. The property owner will provide annual self-certification that inspection and maintenance has been performed, provide I details of the inspection results and maintenance activities, and confirm or update the contact information for the party responsible to ensure inspection and maintenance is performed. 1 Typical Maintenance Indicator(s) for Maintenance Actions Vegetated_BMPs Accumulation of sediment, litter, or debris Remove & properly dispose of accumulated materials, without damage to the vegetation Poor vegetation establishment Reseed, replant or re-establish vegetation Overgrown vegetation Mow or trim as appropriate Erosion due to concentrated irrigation Repair and adjust the irrigation system flow Standing water in biofiltration areas Make appropriate corrective measures such as adjusting irrigation system, removing obstructions of debris or invasive vegetation, clearing underdrains, or repairing/replacing clogged or compacted soils Obstructed inlet or outlet structure Clear obstructions Damage to structural components such Repair or replace as applicable walls or outlet structures Typical Maintenance Indicator(s) for Maintenance Actions Detention Vaults Accumulation of sediment, litter, or debris Remove & properly dispose of accumulated materials Obstructed inlet or outlet structure Clear obstructions Damage to structural components such Repair or replace as applicable as wiers, inlet or outlet structures I I 1 I I I I I I I I I ATTACHMENT 4 City standard Single Sheet BMP (SSBMP) Exhibit [Use the City's standard Single Sheet BMP Plan.] 1 I EE I I I I I I I I I I / co co co Co- / / / i i I f ..-_--__.-•- - __ _________ __ SCALE. 1"=lO' ES S No. 36190 Exp. 6/30/18 OF C ILL CIVIV PARTY RESPONSIBLE FOR MAINTENANCE: NEIL A. MARliN 1878 SHADE TREE DRIVE SAN MARCOS, CA 92078 (760) 920—J208 :;:E Y R. BROWN SO WARDS AND BROV'N ENGINEERING, INC 2187 NEWCASTLE AVENUE, STE 103 CARDIFF BY THE SEA, CA 92007 (760) 436-8500 JOB NO. 13-036 5/02/17 SOWARDS & BROWN ENGINEERING CONSULTING ENGINEERS 2187 NEWCASTLE AVENUE SUITE 103 CARDIFF BY THE SEA, CA., 92007 TEL 760/436-8500 FAX 760/436-8603 BMP TABLE BMP ID # BMP TYPE SYMBOL CASQA NO. - QUAN 17TY DRA WWG NO, SHEET NO. (s) INSPECTiON FREQUENCY MAINTENANCE FREQUENCY SOURCE CONTROL ROOF DRAIN TO SD-11 7 EA. LANDSCAPING — 3, 4 ANNUALLY ANNUALLY EFFICIENT 1RRIGA liON SYSTEMS SD-12 TREA TMEN T CON TROL BIORL IRA liON BASIN TC-32 359 SF — 3, 4 QUARTERLY SEMI—ANNUALLY HYDROMODIF1CA 1/ON DRY VAULT I MP-50 - 359 SF — 4 QUARTERLY SEMI—ANNUALLY LOW IMPACT DESIGN (L.LD.) CONSER VA liON OF NA TURAL DRAINAGES, WELL DRAINED SOILS AND SIGNIFICANT LID 2.2.1 VEGE TA liON MINIMIZE DIS77/RBANCE TO NATURAL DRAINAGES LID 2.2.2 MINIMIZE SOIL COMPAC11ON LID 2.2.4 PER I.'lOUS PAVEMENTS LID 3.2 260 SF - 3 BMP NOTES: 1, THESE BMPS ARE MANDATORY TO BE INSTALLED PER MANUFACTURER'S RECOMMENDA liONS OR THESE PLANS. NO CHANGES TO THE PROPOSED BMPS ON THIS SHEET WiTHOUT PRIOR APPROVAL FROM THE CITY ENGINEER. NO SUBS11RJ liONS TO THE MATERIAL OR TYPES OR PLAN 11NG TYPES WiTHOUT PRIOR APPROVAL FROM THE CITY ENGINEER. NO OCCUPANCY WLL BE GRANTED UN11L THE CI' INSPEC11ON STAFF HAS INSPECTED THIS PROJECT FOR APPROPRIA iF BMP CONSTRUCT/ON AND INS TALLA TION. REFER TO MAINTENANCE AGREEMENT DOCUMENT. SEE PROJECT SWAMP FOR ADD! T1ONAL INFORMA liON. n CITY OF CARLSBAD ENGINEERING DEPARTMENT 1 SINGLE SHEET BMP SITE PLAN MARTIN RESIDENCE RECORD COPY INITIAL DATE PROJECT NO. HMP 15-01 INITIAL REVISION DESCRIPTION --rDATE DATE INITIAL DATE INITIAL DRAWING NO. N/A ENGINEER OF WORK OTHER APPROVAL CITY APPROVAL . -•