Loading...
The URL can be used to link to this page
Your browser does not support the video tag.
Home
My WebLink
About
PD 2020-0008; CHURCH RESIDENCE; STORM WATER QUALITY MANAGEMENT PLAN; 2020-08-18
CITY OF CARLSBAD PRIORITY DEVELOPMENT PROJECT (PDP) STORM WATER QUALITY MANAGEMENT PLAN (SWQMP) FOR CHURCH RESIDENCE PD2020-0008 ORA WI NG No. 524-6A GR2020-0015 ENGINEER OF WORK: PREPARED FOR: BARRY A. CHURCH AND SHANNA L. CHURCH 621 POLARIS DRIVE ENCINITAS, CA 92024 PREPARED BY: SOWARDS AND BROWN ENGINEERING, INC. 2187 NEWCASTLE AVE., SUITE 103 CARDIFF, CA 92007 (760) 436-8500 DATE: 8/18/2020 ,. TABLE OF CONTENTS 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 1a: DMA Exhibit Attachment 1b: Tabular Summary of DMAs and Design Capture Volume Calculations Attachment 1c: Harvest and Use Feasibility Screening (when applicable) Attachment 1d: Categorization of Infiltration Feasibility Condition (when applicable) Attachment 1e: Pollutant Control BMP Design Worksheets / Calculations 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 Attachment 2d: Flow Control Facility Design Attachment 3: Structural BMP Maintenance Thresholds and Actions Attachment 4: Single Sheet BMP (SSBMP) Exhibit \ CERTIFICATION PAGE Project Name: CHURCH RESIDENCE Project ID: 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. RANDY R. BROWN Print Name SOWARDS AND BROWN ENGINEERING, INC. Company 8/18/2020 Date ,,. o.36190 p. 6/30/2022 *' ~~ ~~ ......::;:,~ ,-=--:::::; ...... FIGURE 2.1 CITY OF OCEANSIDE PACIFIC OCEAN 78 CITY OF ENCINITAS VICINITY MAP N. T.S. THOMAS BROTHERS No. 1126-Gl CITY OF VISTA NOT TO SCALE MARCOS Y OF N E-34 Page 1 of 4 REV 02/16 Development Services Land Development Engineering 1635 Faraday Avenue (760) 602-2750 www.carlsbadca.gov STORM WATER STANDARDS QUESTIONNAIRE E-34 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: PROJECT ID: ADDRESS: APN: The project is (check one): New Development Redevelopment The total proposed disturbed area is: ________ ft2 (________) acres The total proposed newly created and/or replaced impervious area is: ________ ft2 (________) 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 1 and follow the instructions. When completed, sign the form at the end and submit this with your application to the city. Adams Street Church Residence 11,639 0.27 0.208,514 206-200-04 PD2020-008 C cityof Carlsbad ~ □ E-34 Page 2 of 4 REV 04/17 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 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: a) Designed and constructed to direct storm water runoff to adjacent vegetated areas, or other non- erodible permeable areas; 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 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? 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 3 of 4 REV 04/17 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 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, 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 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 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 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 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 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 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 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 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 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 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. □ &ZI □ ~ □ &ZI □ fl! &ZI □ □ fl! ~ □ □ fl! □ ~ □ ~ □ ~ E-34 Page 4 of 4 REV 04/17 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. Total proposed newly created or replaced impervious area (B) = _________________________sq. ft. Percent impervious area created or replaced (B/A)*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 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. 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: Applicant Title: Applicant Signature: Date: * 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 By: Date: Project ID: □ □ ~ □ □ □ □ SITE INFORMATION CHECKLIST Project Summary Information Project Name Church Residence Project ID Project Address Adams Street Carlsbad, CA 92008 Assessor's Parcel Number(s) (APN(s)) 206-200-04 Project Watershed (Hydrologic Unit) Carlsbad 904 Parcel Area 0.49 Acres (21,203 Square Feet) Existing Impervious Area (subset of Parcel Area) 0 Acres (0 Square Feet) Area to be disturbed by the project (Project Area) 0.27 Acres (11,639 Square Feet) Project Proposed Impervious Area (subset of Project Area) 0.20 Acres (8,514 Square Feet) Project Proposed Pervious Area (subset of Project Area) 0.07 Acres (3,125 Square Feet) Note: Proposed Impervious Area + Proposed Pervious Area = Area to be Disturbed by the Project. This may be less than the Parcel Area. 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 Land Cover Includes (select all that apply): Vegetative Cover Non-Vegetated Pervious Areas Impervious Areas Description / Additional Information: 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: Southerly end of subject lot extends into Agua Hedionda Lagoon. 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 ‘S’ shaped driveway. Stairs and concrete walkways will provide access on the West side 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 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. Description of Proposed Site Development and Drainage Patterns Project Description / 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, concrete pavers 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 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 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 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 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 Appendix 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 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): 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: 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 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 natural terrain to the Agua Hedionda Lagoon. See the “Technical Memorandum: SWMM Modeling for Hydromodification Compliance of Church Residence” report by Tory R. Walker Engineering dated September 29, 2019, under separate cover, for sizing and drawdown calculations. Vector Control Plan to be submitted with Construction Drawings. 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: Discussion / Additional Information: (optional) 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. 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 buffer limits. 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. E-36 Page 1 of 4 Revised 09/16 Development Services Land Development Engineering 1635 Faraday Avenue (760) 602-2750 www.carlsbadca.gov STANDARD PROJECT REQUIREMENT CHECKLIST E-36 Project Information Project Name: Project ID: DWG No. or Building Permit No.: 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 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 Yes No N/A Discussion/justification if SC-1 not implemented: SC-2 Storm Drain Stenciling or Signage 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 Dispersal Yes No N/A Discussion/justification if SC-3 not implemented: C cityof Carlsbad □ □ □ □ □ □ □ □ □ E-36 Page 2 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 Wind Dispersal Yes No N/A Discussion/justification if SC-4 not implemented: SC-5 Protect Trash Storage Areas from Rainfall, Run-On, Runoff, and Wind Dispersal 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). On-site storm drain inlets Yes No N/A Interior floor drains and elevator shaft sump pumps Yes No N/A Interior parking garages Yes No N/A Need for future indoor & structural pest control Yes No N/A Landscape/Outdoor Pesticide Use Yes No N/A Pools, spas, ponds, decorative fountains, and other water features Yes No N/A Food service Yes No N/A Refuse areas Yes No N/A Industrial processes Yes No N/A Outdoor storage of equipment or materials Yes No N/A Vehicle and Equipment Cleaning Yes No N/A Vehicle/Equipment Repair and Maintenance Yes No N/A Fuel Dispensing Areas Yes No N/A Loading Docks Yes No N/A Fire Sprinkler Test Water Yes No N/A Miscellaneous Drain or Wash Water Yes No N/A Plazas, sidewalks, and parking lots Yes No N/A For “Yes” answers, identify the additional BMP per Appendix E.1. Provide justification for “No” answers. □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ 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 Yes No N/A Discussion/justification if SD-1 not implemented: SD-2 Conserve Natural Areas, Soils, and Vegetation Yes No N/A Discussion/justification if SD-2 not implemented: SD-3 Minimize Impervious Area Yes No N/A Discussion/justification if SD-3 not implemented: SD-4 Minimize Soil Compaction Yes No N/A Discussion/justification if SD-4 not implemented: SD-5 Impervious Area Dispersion Yes No N/A Discussion/justification if SD-5 not implemented: I ID ID ID ID ID ID ID ID ID ID ID ID ID ID ID E-36 Page 4 of 4 Revised 09/16 Site Design Requirement (continued) Applied? SD-6 Runoff Collection Yes No N/A Discussion/justification if SD-6 not implemented: SD-7 Landscaping with Native or Drought Tolerant Species Yes No N/A Discussion/justification if SD-7 not implemented: SD-8 Harvesting and Using Precipitation Yes No N/A Discussion/justification if SD-8 not implemented: I ID ID ID ID ID ID ID ID ID 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. Runoff from the proposed roof and hardscape will be diverted to various planters around the residence. Due to the the site’s hillside topographic conditions and proposed basement construction infiltration BMP’s are not recommended. Infiltration BMPs could significantly increase the risk of geotechnical instability. BMP’s designed for storage and filtration are appropriate for the project site. 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. Since infiltration is not feasible due to geotechnical factors, an impervious liner will be used. 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. 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 be a green street feature as DMA 1 will be a green street. Self-Mitigating areas consist of natural or landscaped areas that drain directly to the Lagoon and is hydraulically separate from DMAs that contain permanent storm water pollutant control BMPs [Continue on next page as necessary.] Chapter 5: Storm Water Pollutant Control Requirements for PDPs chart. This section is applicable whether or not hydromodification management requirements apply, however the overall sequencing of project development may be different if hydromodification management requirements apply. Step 1: Evaluate at DMA Scale Step lA: Is the DMA "Self- mitigating" or "De minimis" or "Self-retaining"? Refer to Section 5.2 Yes No 1-----.._ ___ _, Yes Step 2A: Implement Harvest and use BMPs* Refer to Section 5.5.1.1 Step 1B: Adjust runoff factor to account for site design BMPs and estimate DCV Refer to Section 5.3, B.1 & B.2 No See Figure 5-2 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 Chapter 5: Storm Water Pollutant Control Requirements for PDPs Step 3A&B: Full Infiltration Condition Refer to Section 5.5.1.2 Step 3C: Compute Sizing Requirements Refer to Appendix B.4 rtep 4B: lmplemerit BMP using maximum feasible footprint and document why tl>e r main: g B'VIP siz could not fit on sit Re t'l , S arc Step S: e t Flow thru Treatment Control No* AND BMPs Re tc, ~ c 10 1 5 , 4 1-----1~ ar,c A iper drx El , Step 3A&B: Partial Infiltration Condition Refer to Section 5.5.2 Step 3C: Compute Sizing Requirements Refer to Appendix B.5 St p SA Partic µate in Alt native Comp nc Program l{efe r •-• ~r 1 f Step 3A&B: No Infiltration Condition Refer to Section 5.5.3 Step 3C: Compute Sizing Requirements Refer to Appendix B.5 Yes Step4A: Design BMP for the required size, per design criteria and considerations listed in the fact sheets Refer to Appendix E 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 * Carlsbad has not adopted an Alternative Compliance Program. Redesign the project to capture the remaining DCV using biofiltration. Refer to Appendix B.5 and E. FIGURE 5-2. Stonn Water Pollutant Control BMP Selection Flow Chart 5-3 February 2016 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 __524-A6__ Sheet No. 3 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): 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 __524-A6__ Sheet No. 3 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): 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 __524-A6__ Sheet No. 4 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): 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 __524-A6__ Sheet No. 4 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): Structural BMP Summary Information [Copy this page as needed to provide information for each individual proposed structural BMP] Structural BMP ID No. IMP 7 DWG __524-A6__ Sheet No. 4 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): Structural BMP Summary Information [Copy this page as needed to provide information for each individual proposed structural BMP] Structural BMP ID No. IMP 9 DWG __524-A6__ Sheet No. 4 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): Structural BMP Summary Information [Copy this page as needed to provide information for each individual proposed structural BMP] Structural BMP ID No. IMP 10 DWG __524-A6__ Sheet No. 4 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): 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 ATTACHMENT 1a N I -l!2 as i ~ "' -"' i;5 !fl - /! ~ I IMP 3 BIOFIL TRA TION BASIN 110 SF OMA 3 DRAINS TO IMP 3 4,714 SF 83% IMPERVIOUS I li:J I ,::l::::.-----.....1 I t;._____, GR EN STREt;f f 1,4 3 SF J I PERVI CONCRET[ SIDEWALK I 64 , , I , l , l fR, l . [' l ,,__,_,6,214 , l I I I I , I ~ l I I I I I I I I I I I ...._ -, OMA 2 ..._ I Ltb1 DRAINS TO IM 2 1,420 SF 87% IMPERVIOUS IMP 2 BIOFIL TRA TION BASIN 40 SF ' ' ' OMA 4 DRAINS TO IMP 5 551 SF 100% IMPERVIOUS OMA 6 DRAINS TO IMP 6 1,419 SF 97% IMPERVIOUS OMA 5 DRAINS TO IMP 5 789 SF 95% IMPERVIOUS DMA EXHIBIT IMP 5 BIOFIL TRA TION BASIN 36 SF ii \ I/ ~ ii ,, ,, ,, 11 11 ii 11 11 I OMA 7 DRAINS TO IMP 7 303 SF 95% IMPERVIOUS IMP 7 BIOFIL TRA TION BASIN 15 SF OMA 9 DRAINS TO IMP 9 416 SF 89% IMPERVIOUS IMP 9 BIOFIL TRA TION BASIN 44 SF I ' IMP 10 DETENTION VAULT 373 SF UNDERGRO OTTO!./ 19. I I _L_ I \ L -..J .... C)"' C) Q_ OMA B DRA1t s TO IMP 6 380 SF l 100% MPER'l(OUS " DM\ 11 I SELF\ MITIG TING 8,02i SF / I 18.35' FROM OP[RTY MONU [NT TO 100' UFFER LINE I I I X I I I I I I I I 1 /1 I I I i I I I I I I I I I ~I ..--..--r DE MINIMU1 IMP 6 BIOFIL TRA TION BASIN 42 SF 154 SF I OMA TABULAR SUMMARY OMA ID OMA AREA OMA TYPE OMA 1 1,493 SF GREEN STREET DMA 2 1,420 SF ORA/NS TO IMP 2 IMP 2 40 SF BIOFIL TRA TION BASIN OMA 3 4,714 SF DRAINS TO IMP 3 IMP 3 110 SF BIOFIL TRA TION BASIN OMA 4 551 SF DRAINS TO IMP 5 OMA 5 789 SF DRAINS TO IMP 5 IMP 5 36 SF BIOFIL TRA TION BASIN OMA 6 1,419 SF DRAINS TO IMP 6 IMP 6 42 SF BIOFIL TRA TION BASIN OMA 7 303 SF DRAINS TO IMP 7 IMP 7 15 SF BIOFIL TRA TION BASIN OMA 8 380 SF DRAINS TO IMP 6 OMA 9 416 SF DRAINS TO IMP 9 IMP 9 44 SF BIOFIL TRA TION BASIN IMP 10 373 SF DETENTION VAULT OMA 11 8,021 SF SELF MIT/GA TING DE MIN/MIS 154 SF DE MIN/MIS TOTAL SITE 19,660 SF OMA NOTES: 1. Sil[ IS HYDROLOG/C GROUP '8' --====:)>= =< < SCALE: 1"=10' ,/ ,/ ,/ ------ 2. APPROX/MA l[ DEPTH TO GROUNDWA l[R IS 25 FEET. -------------..J I ___, I , , I , , I , I I , , I , , I , , I I , I , , I , , I -~' I , , ------- OMA EXHIBIT JOB NO. 18-045 B/18/20 SOWARDS & BROWN ENGINEERING CONSUL TING ENGINEERS 2187 NEWCASTLE AVENUE SUITE 1 03 CARDIFF BY THE SEA, CA., 92007 TEL. 760/436-8500 FAX 760/436-BBOa (j D~,\DR~A:'V,N:'G':FILES~\~Tin.E~SH:'EETS~\:'GRAG~IN::G~Tin.E~SHEET~.DWG~R~E'll=SED~,0~2/1~5/1~7-----------------------------------------------------------------------------------------------------------.1 ATTACHMENT 1c 9.3 gal/resident/day x 1.5 days x 8 Residents x 1 CF/7.48 gal = 15 CF 365 Appendix I: Forms and Checklists 1. Is there a demand for harvested water (check all that apply) at the project site that is reliably present during the wet season? IZI Toilet and urinal flushing D Landscape irrigation D 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. [Provide a summary of calculations here] 3. Calculate the DCV using worksheet B.2-1. DCV = ____ (cubic feet) 3a. Is the 36 hour demand greater than or equal to the DCV? D Yes / ~ No c:::> ~ 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. 3b. Is the 36 hour demand greater than 0.25DCV but less than the full DCV? D Yes I No c:=> ~ 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. Is harvest and use feasible based on further evaluation? D Yes, refer to Appendix E to select and size harvest and use BMPs. ~ No, select alternate BMPs. 1-2 3c. Is the 36 hour demand less than 0.25DCV? ~ Yes t Harvest and use is considered to be infeasible. February 2016 ATTACHMENT 1d 7840 EL CAJON BLVD., SUITE 200 ■LA MESA, CALIFORNIA 91942 Phone: (619) 462-9861 ♦ Email: clamonte@flash.net ♦ Fax: (619) 462-9859 TO: SUBJECT: REFERENCES: In accordance with the request of Sowards & Brown Engineering and as required by the City of Carlsbad, we have prepared Form I-8 from the City of Carlsbad, BMP Design Manual - Appendices (February 16, 2016). It was determined that infiltration is not feasible due to geotechnical factors. If you should have any questions after reviewing this report, please do not hesitate to contact our office. This opportunity to be of professional service is sincerely appreciated. Respectfully submitted, C. W. La Monte Company Inc. _______________________________________ Clifford W. La Monte, R.C.E. 25241, G.E. 0495 Job No. 18 7072July 18, 2019 Infiltration Feasibility - Form I-8 Proposed Church Residence West of and Adjacent to 4485 Adams Street Carlsbad, CA, 92008 APN 206-200-04 McCullough Design Development 10531 4S Commons Dr #700 San Diego, CA 92127 Report of Limited Geotechnical Investigation, Proposed Church Residence West of and Adjacent to 4485 Adams Street, Carlsbad, CA, 92008, APN 206-200-04, by C.W. La Monte Company, Inc., dated November 15, 2018 12/31/2019 12/31/2019 C. W. ta M<ante Cmnp•J Ifm:t. vo··1 a di r' Y1 1'tla to rs Appendix I: Forms and Checklists Categorization of Infiltration Feasibility Form 1-8 Condition Part 1 -Full Infiltration Feasibili!y 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 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: Yes No 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: Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative discussion of study/ data source applicability. 1-3 February 2016 Appendix I: Forms and Checklists Criteri a 3 Form 1-8 Page 2 of 4 Screening Question 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: Yes No 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: Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative discussion of study/ data source applicability. Partl 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 11EP in the MS4 Permit. Additional testing and/ or studies may be required by the City to substantiate findings. 1-4 February 2016 Appendix I: Forms and Checklists Form 1-8 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 5 Screening Question 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: Yes No 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: 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. 1-5 February 2016 Appendix I: Forms and Checklists Criteria 7 Form 1-8 Page 4 of 4 Screening Question 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: Yes No 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: 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. Part2 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. 1-6 February 2016 ATTACHMENT 1e Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods B-10 February 2016 Worksheet B.2-1. DCV Design Capture Volume Worksheet B-2.1 1 85th percentile 24-hr storm depth from Figure B.1-1 d= inches 2 Area tributary to BMP (s) A= acres 3 Area weighted runoff factor (estimate using Appendix B.1.1 and B.2.1)C= unitless 4 Tree wells volume reduction TCV= cubic-feet 5 Rain barrels volume reduction RCV= cubic-feet 6 Calculate DCV = (3630 x C x d x A) – TCV - RCV DCV= cubic-feet IMP 2 0.60 0 0 0.03 0.80 52 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) 0 0 0 6 6 IMP 2 52 18 40 6 46 69 20 42 12 35 35 1420 0.80 34 34 I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods B-10 February 2016 Worksheet B.2-1. DCV Design Capture Volume Worksheet B-2.1 1 85th percentile 24-hr storm depth from Figure B.1-1 d= inches 2 Area tributary to BMP (s) A= acres 3 Area weighted runoff factor (estimate using Appendix B.1.1 and B.2.1) C= unitless 4 Tree wells volume reduction TCV= cubic-feet 5 Rain barrels volume reduction RCV= cubic-feet 6 Calculate DCV = (3630 x C x d x A) – TCV - RCV DCV= cubic-feet 0.60 0 0 IMP 3 185 0.11 0.77 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) 0 0 0 6 6 IMP 3 18 4714 110 110 12 42 185 0.77 110 17 168 252 72 126 126 I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods B-10 February 2016 Worksheet B.2-1. DCV Design Capture Volume Worksheet B-2.1 1 85th percentile 24-hr storm depth from Figure B.1-1 d= inches 2 Area tributary to BMP (s) A= acres 3 Area weighted runoff factor (estimate using Appendix B.1.1 and B.2.1) C= unitless 4 Tree wells volume reduction TCV= cubic-feet 5 Rain barrels volume reduction RCV= cubic-feet 6 Calculate DCV = (3630 x C x d x A) – TCV - RCV DCV= cubic-feet 0.60 0 0 0.01 0.90 20 IMP 4 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) 0 0 0 6 6 18 36 5 42 12 20 15 23 6 11 11 551 0.90 15 15 IMP 4 I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods B-10 February 2016 Worksheet B.2-1. DCV Design Capture Volume Worksheet B-2.1 1 85th percentile 24-hr storm depth from Figure B.1-1 d= inches 2 Area tributary to BMP (s) A= acres 3 Area weighted runoff factor (estimate using Appendix B.1.1 and B.2.1) C= unitless 4 Tree wells volume reduction TCV= cubic-feet 5 Rain barrels volume reduction RCV= cubic-feet 6 Calculate DCV = (3630 x C x d x A) – TCV - RCV DCV= cubic-feet 0.60 0 0 IMP 5 0.88 0.02 38 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) 0 0 0 6 6 IMP 5 0.88 38 18 36 5 33 50 14 42 12 25 25 789 21 21 I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods B-10 February 2016 Worksheet B.2-1. DCV Design Capture Volume Worksheet B-2.1 1 85th percentile 24-hr storm depth from Figure B.1-1 d= inches 2 Area tributary to BMP (s) A= acres 3 Area weighted runoff factor (estimate using Appendix B.1.1 and B.2.1) C= unitless 4 Tree wells volume reduction TCV= cubic-feet 5 Rain barrels volume reduction RCV= cubic-feet 6 Calculate DCV = (3630 x C x d x A) – TCV - RCV DCV= cubic-feet 0.60 0 0 IMP 6 0.03 0.88 57 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) 0 0 0 6 6 IMP 6 57 42 38 0.88 37 37 18 12 42 6 51 77 22 38 1418 I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods B-10 February 2016 Worksheet B.2-1. DCV Design Capture Volume Worksheet B-2.1 1 85th percentile 24-hr storm depth from Figure B.1-1 d= inches 2 Area tributary to BMP (s) A= acres 3 Area weighted runoff factor (estimate using Appendix B.1.1 and B.2.1) C= unitless 4 Tree wells volume reduction TCV= cubic-feet 5 Rain barrels volume reduction RCV= cubic-feet 6 Calculate DCV = (3630 x C x d x A) – TCV - RCV DCV= cubic-feet 0.60 0 0 IMP 7 0.01 19 0.86 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) 0 0 0 6 6 IMP 7 19 15 7 303 8 8 18 12 42 2 17 26 13 13 0.86 I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods B-10 February 2016 Worksheet B.2-1. DCV Design Capture Volume Worksheet B-2.1 1 85th percentile 24-hr storm depth from Figure B.1-1 d= inches 2 Area tributary to BMP (s) A= acres 3 Area weighted runoff factor (estimate using Appendix B.1.1 and B.2.1) C= unitless 4 Tree wells volume reduction TCV= cubic-feet 5 Rain barrels volume reduction RCV= cubic-feet 6 Calculate DCV = (3630 x C x d x A) – TCV - RCV DCV= cubic-feet 0.60 0 0 0.01 20 0.90 IMP 8 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) 0 0 0 6 6 10 10 20 18 12 42 10 2 18 380 0.90 38 8 14 14 IMP 8 I Appendix B: Storm Water Pollutant Control Hydrologic Calculations and Sizing Methods B-10 February 2016 Worksheet B.2-1. DCV Design Capture Volume Worksheet B-2.1 1 85th percentile 24-hr storm depth from Figure B.1-1 d= inches 2 Area tributary to BMP (s) A= acres 3 Area weighted runoff factor (estimate using Appendix B.1.1 and B.2.1) C= unitless 4 Tree wells volume reduction TCV= cubic-feet 5 Rain barrels volume reduction RCV= cubic-feet 6 Calculate DCV = (3630 x C x d x A) – TCV - RCV DCV= cubic-feet 0.60 0 0 0.01 IMP 9 0.82 18 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) 0 0 0 6 6 IMP 9 416 10 10 18 44 7 11 18 42 12 17 5 8 8 0.82 I 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 To be completed following initial City review of proposed development ATTACHMENT 2a N /! ~ a-----1,L25• I ------+-1----25• PERVI S CONCRETE SIDEWALK I PERVI CONCRETE SIDEWALK () I I 64 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 t A iii f'j @ u m (ii u IJ -- HMP EXHIBIT -=::::::::)::= =~ __ .,.< SCALE: 1"=10' • --------'!..3::1•43"[ 291_44• I 1~ I I I I I I I L_ ii I/ ~ ii ,, ,, ,, 11 11 ii 11 11 ,_ -..J .... C)"' C) Q_ 19.70 FLAT I JUNcnON Box \IE 18.70 ( \poc,1 EME, GENCY 111:/R\ UPP~ ORIFICE (~f4.00 LOWE,~OR/FICE IE \9.30 "' ---- BY-PASS 1-1 -------- I ' I I -------- I I I I I I I I I I ________ ,_ _______ I ;I I ---------1--I J(. -----'/ I -------.1{, ------..J I I I I I I I I I ____, I I I I I I I 100' 111:TLAND BUFFER I I \ \ \ Sc! \ \ \ \ I. , -;-~-- \ \ \ \ I I I \ \ \ \ .-- \ ----\ X--------------1--- I HMP NOTES: 1. SITE IS HYDROLOGIC GROUP 'B' I I ---I -------- 2. APPROX/MA TE DEPTH TO GROUNDWATER IS 25 FEET. J. SEE Sll!,/M MODELING MEMORANDUM DA TED SEPTEMBER 29, 2019 BY TORY R. WALKER ENGINEERING FOR HYDROMOD/FICA nON CALCULA nONs ------ I I I /, I ~ I t--· " l,,t, ,;ii? I ;!t i ~ I I I I I I I I I ----;' I I I HMP EXHIBIT JOB NO. 18-045 8/18/20 SOWARDS & BROWN ENGINEERING CONSUL TING ENGINEERS 2187 NEWCASTLE AVENUE SUITE 1 03 CARDIFF BY THE SEA, CA., 92007 TEL. 760/436-8500 FAX 760/436-BBOa (j D,,\DR=A'll.=N~G'::FILES='\TI~n.E~SH:EETS~\G:RAG:l:NG~TI~n.E':":SH:EET~.D:WG~R:E'll~SED~,0~2/1~5~/17~-------------------------------------------------------------------------------------------------------------------------------------.1 ATTACHMENT 2b ATTACHMENT 2d TECHNICAL MEMORANDUM TO: Barry and Shanna Church 621 Polaris Drive Encinitas, CA 92024 FROM: Tory Walker, PE, CFM, LEED GA DATE: September 29, 2019 RE: Summary of SWMM Modeling for Hydromodification Compliance of the Church Residence, City of Carlsbad, CA. INTRODUCTION This technical memorandum summarizes the approach used to model the proposed Church Residence project in the City of Carlsbad, CA, using the Environmental Protection Agency (EPA) Storm Water Management Model 5.1 (SWMM). SWMM analyses were prepared for the pre- and post-developed conditions at the project site to determine if the proposed underground storage vault meets Hydromodification Management Plan (HMP) requirements. The San Diego Regional Water Quality Control Board (SDRWQCB) established these requirements in the Model BMP Design Manual San Diego Region1 (BMPDM) for the County of San Diego Copermittees, which includes the City of Carlsbad. SWMM MODEL DEVELOPMENT The Church Residence project proposes to develop an existing site, which is currently undeveloped, located on Adams Street, east of its interception with Highland Drive, in the City of Carlsbad. Two (2) SWMM scenarios were prepared for this study, one for the pre-developed and another for the post- developed conditions. One Point of Compliance (POC-1) has been identified for the project site, as shown on the exhibits in Attachment 5. For both SWMM scenarios, flow duration curves were prepared for POC-1 to determine if the proposed underground vault is sufficient to meet the current HMP requirements. The input data required to develop SWMM analyses include rainfall, watershed characteristics, and BMP configurations. The Oceanside gauge from the Project Clean Water website was used for this study, since it is the most representative of the site precipitation due to elevation and proximity to the project site. Evaporation for the site was modeled using average monthly values provided in the BMPDM. The existing condition site was modeled with Type B hydrologic soil, as determined from the Natural Resources Conservation Service (NRCS) Web Soil Survey. Type B soil has been assumed in post- developed conditions to account for the anticipated fill soils onsite, as required by the BMPDM. TORY R. WALKER ENGINEERING RELIABLE SOLUTIONS IN WATER RESOURCES WATERSHED, FLOODPLAIN es'., STORM WATER MANACEMENT · RIVER RESTORATION· FLOOD FACILITIES DESICN · SEDIMENT es'., EROSION 122 CIVIC CENTER DRIV E, SUITE 206, VISTA CA 92084 • 760-414-9212 • TRWENGINEERING.COM Church Residence HMP Memo September 29, 2019 2 Job # 575-01 HMP MODELING POC-1 is located along the southeastern project site boundary (see Site maps in Attachment 5). In existing conditions, the undeveloped DMA 1 drains southerly to POC-1. In proposed conditions, the developed area tributary to POC-1 is drained to underground vault (Hydromodification BMP). Once flow is routed via the proposed BMP, the flow is then discharged to POC-1. Tables 1.1 and 1.2 summarize data for the POC-1 DMAs. The underground vault is responsible for handling hydromodification requirements for POC-1 and has been designed with a maximum surface ponding depth of 4.00 feet. Flows will discharge from the basin via orifice outlets and a weir within the ponding depth of the vault, to POC-1 at the project boundary. An outlet structure will be constructed within the BMP with an emergency weir, such that peak flows can be safely discharged to POC-1 (see dimensions in Tables 2 and 3 below). TABLE 1.1 – SUMMARY OF EXISTING CONDITIONS FOR POC-1 DMA Tributary Area, A (ac) Impervious Percentage, Ip DMA 1 0.2449 0.0% TABLE 1.2 – SUMMARY OF DEVELOPED CONDITIONS FOR POC-1 DMA Tributary Area, A (ac) Impervious Percentage, Ip(2) DMA 1 0. 2347 79.1% BYPASS 1 0.0015 100.0% TOTAL 0.2362* - *Lower area total in the developed condition is the result of the self retaining pool area being removed from totals General Considerations The vault was modeled using the storage element within SWMM. The storage element can model the vault as a detention basin: elevation vs. area, and elevation vs. discharge tables, are needed by SWMM for Modified Puls routing purposes. Detailed outlet structure location and elevations should be shown on the construction plans based on the recommendations of this study. Detailed water quality requirements are not discussed within this technical memo. For further information regarding storm water quality requirements for the project, please refer to the site specific Storm Water Quality Management Plan (SWQMP). -TRWE- Church Residence HMP Memo September 29, 2019 3 Job # 575-01 BMP MODELING FOR HMP PURPOSES Modeling HMP BMPs An underground storage vault is proposed for hydromodification conformance for the project site. Tables 2 and 3 illustrate the dimensions required for HMP compliance according to the SWMM models that were undertaken for the project. TABLE 2 – SUMMARY OF HYDROMODIFICATION BMP: Storage Vault BMP BMP DIMENSIONS FOR POC-1 Vault Surface Area (ft2) Vault Depth (ft) 1 320 5.2 TABLE 3 – SUMMARY OF HMP RISER SURFACE DISCHARGE STRUCTURES BMP OUTLET DIMENSIONS FOR POC-1 LOWER ORIFICE UPPER ORIFICE EMERGENCY WEIR Dimensions Inv. El. (ft) Dimensions Inv. El. (ft) Inv. El.(ft) Length (ft) (# - diameter (in) ) (# - diameter (in) ) 1 1 - 0.3125 0 2 - 0.3125 4.25 4.7 5 FLOW DURATION CURVE COMPARISON A Flow Duration Curve (FDC) was compared at the project’s POC by exporting the hourly runoff time series results from SWMM to a spreadsheet. The FDC was compared between 10% of the existing condition Q2 up to the existing condition Q10. The 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 from 10% of Q2 up to 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 for POC-1 is illustrated in Figure 1 in both normal and logarithmic scale. As can be seen in Figure 1, the FDC for the proposed condition with the HMP facility is within 110% of the curve for the existing condition in both peak flow and duration. The additional runoff volume generated from developing the site will be released to the storm drain system at a flow rate below the 10% Q2 lower threshold. Additionally, the project will maintain peak flow rates between the Q2 and the Q10, as shown in the graphics and also in the peak flow tables in Attachment 1. -TRWE- I I Church Residence HMP Memo September 29, 2019 4 Job # 575-01 SUMMARY This study has demonstrated that the proposed underground vault provided within the Church Residence project is sufficient to meet the current HMP criteria if the cross-sectional area and volume recommended within this technical memorandum, and the respective orifices and outlet structures, are incorporated as specified within the proposed project site. KEY ASSUMPTIONS 1. Type B soils are representative of the existing condition site per the NRCS Web Soil Survey. -TRWE- Church Residence HMP Memo September 29, 2019 5 Job # 575-01 Figure 1. Flow Duration Curve Comparison for POC-1 (logarithmic and normal “x” scale). -TRWE- Flow Duration Curve -Church Residence (POC-1) 0.15 +-'n_.,,.._..-1-· -_· -_· -_· -_·_-_._--+---·_-_·_-_·_-_·_--+---· -_· -_·--+--• -_· -+---·_-_·+--·_-_.f---·--+·--_·+--+--·-_· -_· -_· -_· -_· -_·_-_.-+-·--_·_-_._-_·_-_·_-+-41Ae<>J ~!-s::------------------=----+= --------------~ 0.14 t-~-"::~--. .... .cc-==,-=--=-=-=-=,r ==c+=='t-'="f=f=r'-'-f=r ======="T-=--=-=-=-=t~..-1 cf,--~,-1:.·:~·--·-·----- -·-·-·- ----------·-·-·-·-·-·----·-·-·-·-·-·---·-------·---0.~ ~ ----:= ----~;-----= ---------------~ -----~ ~--~,· -~ ~ .., --Existing 0.11 t------~-------=--------,f---t,-t---+--+--t--+-+--+----l I -I"-,. 0.13 0.12 - --Proposed -·-Qx 0.10 t-~,-.=c,. ======c+:cc.-!,,'l ===c±===!-='-._.:::±,=-=·t-cc.=i=c=lc=±-c=r.==i 0.09 t------------,-..-1----+----t---+--+ .. --+-+--+-t---------+-----+----l 2 t-Qr=====+=-=·-=-=-=-=i·-=-==ct=~="J=l~. I;;'!· ==f='-1'"-4=====-'4====.jf=Q.,..j ; 0.08 """'' .... , -.;, . ........ ... 0.o7 +-----------,-------,f-~-+--+--+-+--P...,,~t---------+-----t--l ~~ '\ 0.06 t----------t-----t--~•~t-----t-----1----t--t----t----1t,----------t-------t-----1 -.. " 0.05 t------------,--------,,----+--... ,..._..,+---+--+-+--+-t--lo-~:::,------+-----t----l 0.04 +-ufl: .. :'i&~-------i-----,f---....,---.,-.-,.t,,.._=~ .. -.. +-.. +-+--------',~-+-----1trS-1~~.z.l 0.03 +-------------,--------,f----+----+---+--+--+"'-~+--------¼+------+----1 0.3Qz -·-·--·-·----·--·---+-·-·-·-·-·-1 ----~• ...... : -------~~----~Qz 0.02 t------------,--------,f----+--+---+--+-+--+-t-~---==-----+--,------+----l -------"-, '\. o.01 +-o=-.-=-1fli=-. _-. _-. _-. _-. _-.-_-.-+-.-_-.---.---.-_-.-+----t-. _-. _-+. _-. _-. +.-_-_-T1-.-_-_+--+-1-_-_ -_-. _-. _-. _-. _-__ -. _-. _-.+--.-_ ... _-.,.c-.~_...-~.--,0;1c+_=-Q=-z---l 0.00 +----------<-----<-------+---+-~-~-+-+---------+------~ 0.001 0.01 Perc;entage of time exceeded [96-t Flow Duration Curve -Church Residence (POC-1) 0.10 Tro=7..=-=ccc-~;;;;;;;;='=C7'=t-aa.c=r..=-=e--c-=-,-e==~=7.a=i-=ccc-=17.a-=-c--'ccc-=======ac-t==--1 _______ I ____________ I ______ _ ]. 0.08 +'-8"--'--"'F-'-"''--'-''F--'--""'--'f"'la:'-'=-P,==f-'--'=-'--"'F--'-=-'--1F-''-='--'-i=-'--"=-j-='--'-'=j-'--""' _-' _-' ~"L'-' _'-' _"' _"-_-'-~7'_"-_-' _-' _"' _'-' ~'i'_"' _"-_'--_"' ~'4=-"1.,rl a --Existing ---Proposed -. -Qx 0.1ft}: · -· - 0.00 +----'-----'-------"---.--------''---<------l----'------'----'----1 0.01 0.02 0.03 Percentage of time exceeded (%) Church Residence HMP Memo September 29, 2019 6 Job # 575-01 REFERENCES [1] – “Model BMP Design Manual San Diego Region – For Permanent Site Design, Storm Water Treatment, and Hydromodification Management”, June 2015, Geosyntec Consultants & Rick Engineering Company. [2] – Order R9-2013-001, California Regional Water Quality Control Board San Diego Region (SDRWQCB). [3] – “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, Tory R. Walker Engineering. [4] – “Handbook of Hydrology”, David R. Maidment, Editor in Chief. 1992, McGraw Hill. ATTACHMENTS 1. Peak Flow Frequency Comparison Tables 2. Flow Duration Curve Comparison Plots and Data 3. Partial Duration Series Data 4. Storage and Rating Curves 5. Drawdown Time Calculations 6. Pre-Developed and Post-Project DMA Exhibits 7. NRCS Soil Map 8. SWMM Input Data 9. SWMM Summary Report -TRWE- ATTACHMENT 1 Q 2 to Q10 Comparison Tables Q2 to Q10 Comparison Table – POC-1 Return Period Existing Condition (cfs) Mitigated Condition (cfs) Reduction, Exist - Mitigated (cfs) 2-year 0.081 0.013 0.068 3-year 0.099 0.038 0.061 4-year 0.119 0.061 0.058 5-year 0.124 0.085 0.039 6-year 0.128 0.086 0.042 7-year 0.137 0.108 0.029 8-year 0.141 0.109 0.032 9-year 0.145 0.111 0.035 10-year 0.152 0.115 0.037 ATTACHMENT 2 FDC Plots (log and natural “x” scale) and Flow Duration Table ATTACHMENT 2 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, for each POC, the flow duration curve in post- development conditions with the proposed BMPs 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 Encinitas HMP 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 TRWE, 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. 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). TRWE 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. 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0 0.01 0.02 0.03 Q ( c f s ) Percentage of time exceeded (%) Flow Duration Curve -Church Residence (POC-1) Existing Proposed Qx Cliii l-·-·- -·-· -·-· ~·-·--·-·-·-·-·-·- -·-· -·-· -·-·-~·-·-·-·-·-·--QlO $L ·-·- -·-· -·-· -·-·--·-·-·-·-·-·- -·-· -·-· -·-·-~--·-··-·-·-·--~9 -· . --. ·--· . --· ·-·-Cr,'t ·-·- -·-· -·-· -·-·--·-·-·-·-·-·- -·-· -·-· -·-·-~--·-··-·-·-·--a; 7 ' ~-. ~ ~ -·-· -·-· ~--·--·-·-·-·-·-·- -·-· -·-· -·-·-~--·-·-·-·-·--Q6 crs·r --·-· -·-· -·-·--·-·-·-·-·-·- -·-· -·-· -·-·-~--·-··-·-·-·---Qs cti"" i" . -"'""" -·-· -·-· ~--·--·-·-·-·-·-·- -·-· -·-· -·-·-~--·-·-·-·-·--o.i • ... 1 l\ l.ti" . 1 ~ ~· . --. ·--· . -~· ·-·-ll.3 I I ~. , .... I "--· I ~. . --. ·--· . --· ·-·-" ~£ ' '--~£ ' -I "' l ---I I ~ " ~ -·-... I ' ' ~ ~--t . ---u.~.....,z -.---.. ~ u.~.....,z ..... ~ ,_ -, -:-......... I 0.3t,:z· -·-·--·-·-·-·-·--~ c-::·-· -·-· ~--·--·-·-·-·-·-·-· -·-·--0.~2 .. _ ~ ----i-----~ ~ -----------... .... "'--~--O.ltt2· -·-·--·-·-·-·-·-·- -·-· -·-· ~--·--·-·-·-·-·-·--~~ ~--· ·o.'tQz 0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10 0.11 0.12 0.13 0.14 0.15 0.16 0.001 0.01 Q ( c f s ) Percentage of time exceeded (%) Flow Duration Curve -Church Residence (POC-1) Existing Proposed Qx n--a-·-·-·-·-·-·-·-·-~--·--·-· -·-·-· -· -. --· ~--·-·-·-·-·-·-·-·-·-!-n ci;bi:--·-·-•.1u ·-·-·-·· ~--·--·-· -·-·-· -·· ~. -~ .. ~--·-·-·-·-·~·-·-·-·-~Q ~ ..... ·-.. -· ·--. --. . . . . . . . . . -.... Ag ='0 ~-~ -·-·-·-·-·-·-·-·-·1 ·-·-·-·-~a; ~--~-·-·-·-·-·-·r ·-·--·-· -·-·-· 7 ---I ~--·-·-;· . ·--~·-·--·-· -·-·-· -· -. --· =·-·-·-·-·-·~----·-·: -Q6 l .L ____ 0s9·-·-·:·-·-·-· -·-· -·--·· ~. -~ .. ~Cls ,...., l.{i"" ·-· ·-. -~~· ·--. -~· ~· . --, . . -1C4 I I -------. L.. ---I I"'\.. . Lli". ·-·-· ~· ~ ~. -~· ~· -·-~· ..... Q.3 I I """ ·--.l . ------ "--· ·-~-·--. --· ~-·-. -"""""' --£ ...... -~ --£ " I """'- l,.. "~ I .... ·--"t I ~ ... -----....... ... ► ~-~------u.~....,z -----· I"-, ' ~-~-2 ..... ~ --~ " ~--·--o 0.3tt2· -. -. -. -. ~--·-·--·-·-·-·-·-· -·-·--►-. -• -• -• -• -• 3Q2 -,_ ----... ~ -------ti .... ... O.ltt2· -· -· -· -· ~--·-·--·-·-·-·-·-·r ·-·-- --·-·-·-·-·-· -. -="'"-'--OttQ2 Flow Duration Curve Data for Church Residence (POC-1), Carlsbad, CA Q2 =0.08 cfs Fraction 10 % Q10 =0.15 cfs Step =0.0014 cfs Count =497370 hours 56.74 years Pass or Q (cfs)Hours > Q % time Hours>Q % time Post/Pre Fail? 1 0.008 134 2.69E-02 121 2.43E-02 90%Pass 2 0.010 131 2.63E-02 114 2.29E-02 87%Pass 3 0.011 130 2.61E-02 112 2.25E-02 86%Pass 4 0.012 125 2.51E-02 108 2.17E-02 86%Pass 5 0.014 124 2.49E-02 105 2.11E-02 85%Pass 6 0.015 123 2.47E-02 95 1.91E-02 77%Pass 7 0.017 122 2.45E-02 80 1.61E-02 66%Pass 8 0.018 120 2.41E-02 73 1.47E-02 61%Pass 9 0.020 117 2.35E-02 58 1.17E-02 50%Pass 10 0.021 117 2.35E-02 54 1.09E-02 46%Pass 11 0.023 116 2.33E-02 54 1.09E-02 47%Pass 12 0.024 105 2.11E-02 49 9.85E-03 47%Pass 13 0.025 105 2.11E-02 48 9.65E-03 46%Pass 14 0.027 102 2.05E-02 48 9.65E-03 47%Pass 15 0.028 98 1.97E-02 47 9.45E-03 48%Pass 16 0.030 96 1.93E-02 46 9.25E-03 48%Pass 17 0.031 96 1.93E-02 41 8.24E-03 43%Pass 18 0.033 94 1.89E-02 41 8.24E-03 44%Pass 19 0.034 90 1.81E-02 40 8.04E-03 44%Pass 20 0.036 89 1.79E-02 40 8.04E-03 45%Pass 21 0.037 87 1.75E-02 37 7.44E-03 43%Pass 22 0.039 84 1.69E-02 37 7.44E-03 44%Pass 23 0.040 84 1.69E-02 26 5.23E-03 31%Pass 24 0.041 83 1.67E-02 25 5.03E-03 30%Pass 25 0.043 82 1.65E-02 25 5.03E-03 30%Pass 26 0.044 80 1.61E-02 25 5.03E-03 31%Pass 27 0.046 80 1.61E-02 25 5.03E-03 31%Pass 28 0.047 67 1.35E-02 24 4.83E-03 36%Pass 29 0.049 64 1.29E-02 23 4.62E-03 36%Pass 30 0.050 57 1.15E-02 22 4.42E-03 39%Pass 31 0.052 57 1.15E-02 22 4.42E-03 39%Pass 32 0.053 57 1.15E-02 22 4.42E-03 39%Pass 33 0.054 56 1.13E-02 22 4.42E-03 39%Pass 34 0.056 54 1.09E-02 20 4.02E-03 37%Pass 35 0.057 52 1.05E-02 20 4.02E-03 38%Pass 36 0.059 51 1.03E-02 19 3.82E-03 37%Pass 37 0.060 51 1.03E-02 18 3.62E-03 35%Pass Detention Optimized Interval Existing Condition Pass or Q (cfs)Hours > Q % time Hours>Q % time Post/Pre Fail? Detention Optimized Interval Existing Condition 38 0.062 51 1.03E-02 18 3.62E-03 35%Pass 39 0.063 50 1.01E-02 18 3.62E-03 36%Pass 40 0.065 49 9.85E-03 18 3.62E-03 37%Pass 41 0.066 48 9.65E-03 18 3.62E-03 38%Pass 42 0.068 47 9.45E-03 17 3.42E-03 36%Pass 43 0.069 46 9.25E-03 17 3.42E-03 37%Pass 44 0.070 43 8.65E-03 17 3.42E-03 40%Pass 45 0.072 41 8.24E-03 17 3.42E-03 41%Pass 46 0.073 38 7.64E-03 17 3.42E-03 45%Pass 47 0.075 36 7.24E-03 17 3.42E-03 47%Pass 48 0.076 35 7.04E-03 16 3.22E-03 46%Pass 49 0.078 35 7.04E-03 15 3.02E-03 43%Pass 50 0.079 33 6.63E-03 15 3.02E-03 45%Pass 51 0.081 33 6.63E-03 15 3.02E-03 45%Pass 52 0.082 32 6.43E-03 15 3.02E-03 47%Pass 53 0.083 32 6.43E-03 15 3.02E-03 47%Pass 54 0.085 32 6.43E-03 15 3.02E-03 47%Pass 55 0.086 32 6.43E-03 13 2.61E-03 41%Pass 56 0.088 32 6.43E-03 11 2.21E-03 34%Pass 57 0.089 31 6.23E-03 11 2.21E-03 35%Pass 58 0.091 31 6.23E-03 11 2.21E-03 35%Pass 59 0.092 30 6.03E-03 11 2.21E-03 37%Pass 60 0.094 29 5.83E-03 11 2.21E-03 38%Pass 61 0.095 27 5.43E-03 11 2.21E-03 41%Pass 62 0.097 26 5.23E-03 11 2.21E-03 42%Pass 63 0.098 26 5.23E-03 11 2.21E-03 42%Pass 64 0.099 22 4.42E-03 11 2.21E-03 50%Pass 65 0.101 21 4.22E-03 11 2.21E-03 52%Pass 66 0.102 21 4.22E-03 11 2.21E-03 52%Pass 67 0.104 20 4.02E-03 11 2.21E-03 55%Pass 68 0.105 18 3.62E-03 11 2.21E-03 61%Pass 69 0.107 18 3.62E-03 11 2.21E-03 61%Pass 70 0.108 18 3.62E-03 11 2.21E-03 61%Pass 71 0.110 18 3.62E-03 10 2.01E-03 56%Pass 72 0.111 18 3.62E-03 8 1.61E-03 44%Pass 73 0.112 18 3.62E-03 8 1.61E-03 44%Pass 74 0.114 18 3.62E-03 8 1.61E-03 44%Pass 75 0.115 17 3.42E-03 8 1.61E-03 47%Pass 76 0.117 17 3.42E-03 8 1.61E-03 47%Pass 77 0.118 16 3.22E-03 8 1.61E-03 50%Pass 78 0.120 16 3.22E-03 8 1.61E-03 50%Pass 79 0.121 16 3.22E-03 8 1.61E-03 50%Pass 80 0.123 15 3.02E-03 8 1.61E-03 53%Pass 81 0.124 12 2.41E-03 8 1.61E-03 67%Pass 82 0.126 12 2.41E-03 8 1.61E-03 67%Pass Pass or Q (cfs)Hours > Q % time Hours>Q % time Post/Pre Fail? Detention Optimized Interval Existing Condition 83 0.127 12 2.41E-03 8 1.61E-03 67%Pass 84 0.128 9 1.81E-03 8 1.61E-03 89%Pass 85 0.130 9 1.81E-03 8 1.61E-03 89%Pass 86 0.131 9 1.81E-03 8 1.61E-03 89%Pass 87 0.133 9 1.81E-03 8 1.61E-03 89%Pass 88 0.134 9 1.81E-03 7 1.41E-03 78%Pass 89 0.136 8 1.61E-03 7 1.41E-03 88%Pass 90 0.137 8 1.61E-03 7 1.41E-03 88%Pass 91 0.139 8 1.61E-03 6 1.21E-03 75%Pass 92 0.140 7 1.41E-03 6 1.21E-03 86%Pass 93 0.141 7 1.41E-03 6 1.21E-03 86%Pass 94 0.143 7 1.41E-03 6 1.21E-03 86%Pass 95 0.144 6 1.21E-03 6 1.21E-03 100%Pass 96 0.146 6 1.21E-03 6 1.21E-03 100%Pass 97 0.147 6 1.21E-03 6 1.21E-03 100%Pass 98 0.149 6 1.21E-03 6 1.21E-03 100%Pass 99 0.150 6 1.21E-03 6 1.21E-03 100%Pass 100 0.152 6 1.21E-03 6 1.21E-03 100%Pass Peak Flows calculated with Cunnane Plotting Position Return Period (years)Pre-dev. Q (cfs)Post-Dev. Q (cfs) Reduction (cfs) 10 0.152 0.137 0.014 9 0.145 0.135 0.010 8 0.141 0.120 0.021 7 0.137 0.110 0.027 6 0.128 0.109 0.019 5 0.124 0.087 0.037 4 0.119 0.080 0.039 3 0.099 0.043 0.056 2 0.081 0.019 0.062 ATTACHMENT 3 List of the “n” largest Peaks: Pre-Development and Post-Development Conditions ATTACHMENT 3 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: P =i−0.4 n+0.2 P =i n+1 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) Church Residence (POC-1) T (Year) Cunnane (cfs) Weibull (cfs) 10 0.15 0.16 Date Posit Weibull Cunnane 9 0.15 0.15 0.047 1/15/1978 57 1.02 1.01 8 0.14 0.14 0.047 1/11/1980 56 1.04 1.03 7 0.14 0.14 0.048 12/10/1965 55 1.05 1.05 6 0.13 0.13 0.048 12/24/1988 54 1.07 1.07 5 0.12 0.12 0.049 3/8/1968 53 1.09 1.09 4 0.12 0.12 0.049 1/6/1979 52 1.12 1.11 3 0.10 0.10 0.049 1/11/2005 51 1.14 1.13 2 0.08 0.08 0.05 2/19/1958 50 1.16 1.15 0.054 11/11/1985 49 1.18 1.18 0.055 2/22/1998 48 1.21 1.20 Note:0.055 2/12/2003 47 1.23 1.23 Cunnane is the preferred 0.056 12/2/1961 46 1.26 1.25 method by the HMP permit.0.056 11/8/2002 45 1.29 1.28 0.058 12/31/2004 44 1.32 1.31 0.062 3/2/1980 43 1.35 1.34 0.064 1/18/1993 42 1.38 1.38 0.066 2/14/1998 41 1.41 1.41 0.067 2/12/1992 40 1.45 1.44 0.068 2/8/1993 39 1.49 1.48 0.071 3/1/1991 38 1.53 1.52 0.071 12/30/1991 37 1.57 1.56 0.073 2/15/1986 36 1.61 1.61 0.073 3/15/1986 35 1.66 1.65 0.074 1/16/1978 34 1.71 1.70 0.074 1/29/1980 33 1.76 1.75 0.076 3/11/1995 32 1.81 1.81 0.079 1/6/2008 31 1.87 1.87 0.079 1/27/2008 30 1.93 1.93 0.081 2/17/1998 29 2.00 2.00 0.088 2/23/1998 28 2.07 2.07 0.092 12/19/1970 27 2.15 2.15 0.093 1/29/1983 26 2.23 2.23 0.094 2/16/1980 25 2.32 2.33 0.094 10/20/2004 24 2.42 2.42 0.096 11/22/1965 23 2.52 2.53 0.098 2/10/1978 22 2.64 2.65 0.098 2/27/1983 21 2.76 2.78 0.098 2/3/1998 20 2.90 2.92 0.1 10/27/2004 19 3.05 3.08 0.104 1/16/1952 18 3.22 3.25 0.105 11/15/1952 17 3.41 3.45 0.114 10/29/2000 16 3.63 3.67 0.117 4/1/1958 15 3.87 3.92 0.123 3/1/1978 14 4.14 4.21 0.123 2/20/1980 13 4.46 4.54 0.123 3/17/1982 12 4.83 4.93 0.128 1/14/1993 11 5.27 5.40 0.128 2/18/2005 10 5.80 5.96 0.135 2/25/1969 9 6.44 6.65 0.14 2/4/1958 8 7.25 7.53 0.143 9/23/1986 7 8.29 8.67 0.153 2/25/2003 6 9.67 10.21 0.186 1/15/1979 5 11.60 12.43 0.187 1/4/1995 4 14.50 15.89 0.22 1/4/1978 3 19.33 22.00 0.222 10/1/1983 2 29.00 35.75 0.246 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) Church Residence (POC-1) T (Year) Cunnane (cfs) Weibull (cfs) 10 0.14 0.14 Date Posit Weibull Cunnane 9 0.13 0.14 0.006 12/6/1966 57 1.02 1.01 8 0.12 0.13 0.006 12/6/1966 56 1.04 1.03 7 0.11 0.11 0.006 12/6/1966 55 1.05 1.05 6 0.11 0.11 0.006 12/6/1966 54 1.07 1.07 5 0.09 0.09 0.006 2/19/1980 53 1.09 1.09 4 0.08 0.08 0.006 2/19/1980 52 1.12 1.11 3 0.04 0.04 0.006 2/19/1980 51 1.14 1.13 2 0.02 0.02 0.007 1/15/1978 50 1.16 1.15 0.007 1/15/1978 49 1.18 1.18 0.007 3/2/1983 48 1.21 1.20 Note:0.007 2/25/2003 47 1.23 1.23 Cunnane is the preferred 0.007 2/25/2003 46 1.26 1.25 method by the HMP permit.0.007 2/25/2003 45 1.29 1.28 0.007 2/26/2003 44 1.32 1.31 0.007 2/26/2003 43 1.35 1.34 0.007 10/27/2004 42 1.38 1.38 0.007 10/27/2004 41 1.41 1.41 0.008 2/4/1958 40 1.45 1.44 0.008 2/4/1958 39 1.49 1.48 0.008 2/4/1958 38 1.53 1.52 0.008 11/30/2007 37 1.57 1.56 0.014 2/22/2008 36 1.61 1.61 0.015 1/12/1980 35 1.66 1.65 0.015 1/12/1980 34 1.71 1.70 0.016 1/15/1979 33 1.76 1.75 0.017 2/15/1986 32 1.81 1.81 0.019 1/29/1980 31 1.87 1.87 0.019 1/29/1980 30 1.93 1.93 0.019 10/1/1983 29 2.00 2.00 0.025 1/25/1969 28 2.07 2.07 0.027 2/23/1998 27 2.15 2.15 0.031 12/5/1966 26 2.23 2.23 0.037 11/22/1965 25 2.32 2.33 0.039 1/18/1952 24 2.42 2.42 0.039 1/11/1980 23 2.52 2.53 0.039 1/11/1980 22 2.64 2.65 0.039 1/11/1980 21 2.76 2.78 0.039 2/18/1980 20 2.90 2.92 0.047 1/18/1993 19 3.05 3.08 0.055 11/22/1996 18 3.22 3.25 0.059 3/3/1983 17 3.41 3.45 0.076 1/16/1993 16 3.63 3.67 0.077 1/9/2005 15 3.87 3.92 0.086 3/8/1968 14 4.14 4.21 0.086 2/23/2005 13 4.46 4.54 0.087 1/6/1979 12 4.83 4.93 0.087 1/11/2005 11 5.27 5.40 0.109 3/1/1991 10 5.80 5.96 0.11 1/16/1978 9 6.44 6.65 0.11 1/29/1980 8 7.25 7.53 0.134 3/17/1982 7 8.29 8.67 0.138 1/4/1978 6 9.67 10.21 0.157 3/1/1978 5 11.60 12.43 0.157 2/20/1980 4 14.50 15.89 0.169 2/25/1969 3 19.33 22.00 0.219 1/4/1995 2 29.00 35.75 0.275 4/14/2003 1 58.00 95.33 Peaks (cfs) Period of Return (Years) ATTACHMENT 4 Elevation vs. Area Curves and Elevation vs. Discharge Curves to be used in SWMM ATTACHMENT 4 ELEVATION vs. AREA The elevation vs. area curves in the model are calculated in Excel and imported into the model. The summary of elevation vs. area for each BMP has been provided on the following pages. The LID surface storage depth beneath the lowest surface discharge structure is accounted for in the LID module as illustrated in Attachment 7. ELEVATION vs. DISCHARGE The total elevation vs. discharge curve is imported from an Excel spreadsheet that calculates the elevation vs. discharge of the outlet system. Elevation vs. discharge relationships are provided for the surface discharge of the biofiltration basin as this is where a Modified Puls routing procedure will be applied in the continuous simulation model. The orifice sizes 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 TRWE 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 conforming 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 structures is provided in Attachment 5 of this memorandum. DISCHARGE EQUATIONS 1) Weir: 𝑄𝑊= 𝐴𝑊·𝐿·𝐻3/2 (1) 2) Slot: As an orifice: 𝑄𝑟=𝐴𝑟·�𝑟·𝑐𝑔·√2𝑖(𝐻−ℎ𝑠 2 ) (2.a) As a weir: 𝑄𝑟=𝐴𝑊·𝐴𝑟·𝐻3/2 (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: 𝑄𝑜=0.25 ·𝜋𝐴2 ·𝑐𝑔·√2𝑖(𝐻−𝐷 2) (3.a) As a weir: Critical depth and geometric family of circular sector must be solved to determined Q as a function of H: 𝑄𝑂2 𝑖=𝐴𝑐𝑟3 𝑇𝑐𝑟 ; 𝐻= 𝑦𝑐𝑟+𝐴𝑐𝑟 2 ·𝑇𝑐𝑟 ; 𝑇𝑐𝑟=2√𝑦𝑐𝑟(𝐴−𝑦𝑐𝑟) ; 𝐴𝑐𝑟= 𝐴2 8 [𝛼𝑐𝑟−𝑠�ℎ𝑛(𝛼𝑐𝑟)] ; 𝑦𝑐𝑟= 𝐷 2 [1 −𝑠�ℎ𝑛(0.5 ·𝛼𝑐𝑟)] (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 of 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 (ft2), top width (ft), critical depth (ft), and angle to the center, respectively. Stage-Storage for Underground Storage 1-1 Facility Type:Vault *Depth (ft)Area (ft2)Maximum Volume (ft3) 5.20 320 1664 1664 0.00 320 0 Outlet structure for Discharge of DMA 1-1 Discharge vs Elevation Table Low orifice 0.3125 "Lower slot Lower Weir Number of orif:1 Number of slots:0 Number of weirs:0 Cg-low:0.62 Invert:3.75 ft Invert:3.63 B 0.02 ft B:0.50 Middle orifice 0.3125 "hslot 0.021 ft Number of orif:2 Cg-middle:0.62 Upper slot Emergency weir invert elev:4.250 ft Number of slots:0 Invert:4.70 ft Invert:0.00 ft B:4.00 ft B:0.00 ft hslot 0.083 ft h*H/D-low H/D-mid Qlow-orif Qlow-weir Qtot-low Qmid-orif Qmid-weir Qtot-med Qslot-low Qslot-upp Qweir Qemerg Qtot (ft)--(cfs)(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 0.0000 0.042 1.600 0.000 0.000 0.001 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.0004 0.083 3.200 0.000 0.001 0.001 0.001 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.0007 0.125 4.800 0.000 0.001 0.004 0.001 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.001 0.167 6.400 0.000 0.001 0.010 0.001 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.001 0.208 8.000 0.000 0.001 0.012 0.001 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.001 0.250 9.600 0.000 0.001 0.013 0.001 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.001 0.292 11.200 0.000 0.001 0.014 0.001 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.001 0.333 12.800 0.000 0.001 0.015 0.001 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.001 0.375 14.400 0.000 0.002 0.016 0.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 0.417 16.000 0.000 0.002 0.017 0.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 0.458 17.600 0.000 0.002 0.018 0.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 0.500 19.200 0.000 0.002 0.018 0.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 0.542 20.800 0.000 0.002 0.019 0.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 0.583 22.400 0.000 0.002 0.020 0.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 0.625 24.000 0.000 0.002 0.021 0.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 0.667 25.600 0.000 0.002 0.021 0.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 0.708 27.200 0.000 0.002 0.022 0.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 0.750 28.800 0.000 0.002 0.023 0.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 0.792 30.400 0.000 0.002 0.023 0.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 0.833 32.000 0.000 0.002 0.024 0.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 0.875 33.600 0.000 0.002 0.025 0.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.002 0.917 35.200 0.000 0.003 0.025 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 *Note: h = head above the invert of the lowest surface discharge opening. h*H/D-low H/D-mid Qlow-orif Qlow-weir Qtot-low Qmid-orif Qmid-weir Qtot-med Qslot-low Qslot-upp Qweir Qemerg Qtot (ft)--(cfs)(cfs)(cfs)(cfs)(cfs)(cfs)(cfs)(cfs)(cfs)(cfs)(cfs) 0.958 36.800 0.000 0.003 0.026 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 1.000 38.400 0.000 0.003 0.026 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 1.042 40.000 0.000 0.003 0.027 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 1.083 41.600 0.000 0.003 0.027 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 1.125 43.200 0.000 0.003 0.028 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 1.167 44.800 0.000 0.003 0.028 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 1.208 46.400 0.000 0.003 0.029 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 1.250 48.000 0.000 0.003 0.029 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 1.292 49.600 0.000 0.003 0.030 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 1.333 51.200 0.000 0.003 0.030 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 1.375 52.800 0.000 0.003 0.031 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 1.417 54.400 0.000 0.003 0.031 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 1.458 56.000 0.000 0.003 0.032 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 1.500 57.600 0.000 0.003 0.032 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 1.542 59.200 0.000 0.003 0.033 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 1.583 60.800 0.000 0.003 0.033 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 1.625 62.400 0.000 0.003 0.034 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 1.667 64.000 0.000 0.003 0.034 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 1.708 65.600 0.000 0.003 0.035 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 1.750 67.200 0.000 0.003 0.035 0.003 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.003 1.792 68.800 0.000 0.004 0.035 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 1.833 70.400 0.000 0.004 0.036 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 1.875 72.000 0.000 0.004 0.036 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 1.917 73.600 0.000 0.004 0.037 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 1.958 75.200 0.000 0.004 0.037 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.000 76.800 0.000 0.004 0.037 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.042 78.400 0.000 0.004 0.038 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.083 80.000 0.000 0.004 0.038 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.125 81.600 0.000 0.004 0.039 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.167 83.200 0.000 0.004 0.039 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.208 84.800 0.000 0.004 0.039 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.250 86.400 0.000 0.004 0.040 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.292 88.000 0.000 0.004 0.040 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.333 89.600 0.000 0.004 0.040 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.375 91.200 0.000 0.004 0.041 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.417 92.800 0.000 0.004 0.041 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.458 94.400 0.000 0.004 0.041 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 h*H/D-low H/D-mid Qlow-orif Qlow-weir Qtot-low Qmid-orif Qmid-weir Qtot-med Qslot-low Qslot-upp Qweir Qemerg Qtot (ft)--(cfs)(cfs)(cfs)(cfs)(cfs)(cfs)(cfs)(cfs)(cfs)(cfs)(cfs) 2.500 96.000 0.000 0.004 0.042 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.542 97.600 0.000 0.004 0.042 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.583 99.200 0.000 0.004 0.042 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.625 100.800 0.000 0.004 0.043 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.667 102.400 0.000 0.004 0.043 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.708 104.000 0.000 0.004 0.044 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.750 105.600 0.000 0.004 0.044 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.792 107.200 0.000 0.004 0.044 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.833 108.800 0.000 0.004 0.045 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.875 110.400 0.000 0.004 0.045 0.004 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.004 2.917 112.000 0.000 0.005 0.045 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 2.958 113.600 0.000 0.005 0.045 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.000 115.200 0.000 0.005 0.046 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.042 116.800 0.000 0.005 0.046 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.083 118.400 0.000 0.005 0.046 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.125 120.000 0.000 0.005 0.047 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.167 121.600 0.000 0.005 0.047 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.208 123.200 0.000 0.005 0.047 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.250 124.800 0.000 0.005 0.048 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.292 126.400 0.000 0.005 0.048 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.333 128.000 0.000 0.005 0.048 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.375 129.600 0.000 0.005 0.049 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.417 131.200 0.000 0.005 0.049 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.458 132.800 0.000 0.005 0.049 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.500 134.400 0.000 0.005 0.049 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.542 136.000 0.000 0.005 0.050 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.583 137.600 0.000 0.005 0.050 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.625 139.200 0.000 0.005 0.050 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.667 140.800 0.000 0.005 0.051 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.708 142.400 0.000 0.005 0.051 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.750 144.000 0.000 0.005 0.051 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.792 145.600 0.000 0.005 0.052 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.833 147.200 0.000 0.005 0.052 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.875 148.800 0.000 0.005 0.052 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.917 150.400 0.000 0.005 0.052 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 3.958 152.000 0.000 0.005 0.053 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 4.000 153.600 0.000 0.005 0.053 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 h*H/D-low H/D-mid Qlow-orif Qlow-weir Qtot-low Qmid-orif Qmid-weir Qtot-med Qslot-low Qslot-upp Qweir Qemerg Qtot (ft)--(cfs)(cfs)(cfs)(cfs)(cfs)(cfs)(cfs)(cfs)(cfs)(cfs)(cfs) 4.042 155.200 0.000 0.005 0.053 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 4.083 156.800 0.000 0.005 0.053 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 4.125 158.400 0.000 0.005 0.054 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 4.167 160.000 0.000 0.005 0.054 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 4.208 161.600 0.000 0.005 0.054 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 4.250 163.200 0.000 0.005 0.055 0.005 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.005 4.292 164.800 1.600 0.005 0.055 0.005 0.001 0.001 0.001 0.000 0.000 0.000 0.000 0.006 4.333 166.400 3.200 0.006 0.055 0.006 0.001 0.002 0.001 0.000 0.000 0.000 0.000 0.007 4.375 168.000 4.800 0.006 0.055 0.006 0.002 0.008 0.002 0.000 0.000 0.000 0.000 0.007 4.417 169.600 6.400 0.006 0.056 0.006 0.002 0.058 0.002 0.000 0.000 0.000 0.000 0.008 4.458 171.200 8.000 0.006 0.056 0.006 0.002 0.245 0.002 0.000 0.000 0.000 0.000 0.008 4.500 172.800 9.600 0.006 0.056 0.006 0.003 0.736 0.003 0.000 0.000 0.000 0.000 0.008 4.542 174.400 11.200 0.006 0.056 0.006 0.003 1.798 0.003 0.000 0.000 0.000 0.000 0.008 4.583 176.000 12.800 0.006 0.057 0.006 0.003 3.818 0.003 0.000 0.000 0.000 0.000 0.009 4.625 177.600 14.400 0.006 0.057 0.006 0.003 7.324 0.003 0.000 0.000 0.000 0.000 0.009 4.667 179.200 16.000 0.006 0.057 0.006 0.003 13.008 0.003 0.000 0.000 0.000 0.000 0.009 4.708 180.800 17.600 0.006 0.057 0.006 0.004 21.749 0.004 0.000 0.000 0.000 0.009 0.019 4.750 182.400 19.200 0.006 0.058 0.006 0.004 34.636 0.004 0.000 0.000 0.000 0.139 0.148 4.792 184.000 20.800 0.006 0.058 0.006 0.004 52.986 0.004 0.000 0.000 0.000 0.344 0.354 4.833 185.600 22.400 0.006 0.058 0.006 0.004 78.368 0.004 0.000 0.000 0.000 0.604 0.614 4.875 187.200 24.000 0.006 0.058 0.006 0.004 112.627 0.004 0.000 0.000 0.000 0.908 0.918 4.917 188.800 25.600 0.006 0.059 0.006 0.004 157.905 0.004 0.000 0.000 0.000 1.251 1.261 4.958 190.400 27.200 0.006 0.059 0.006 0.004 216.661 0.004 0.000 0.000 0.000 1.628 1.638 5.000 192.000 28.800 0.006 0.059 0.006 0.005 291.695 0.005 0.000 0.000 0.000 2.038 2.048 5.042 193.600 30.400 0.006 0.059 0.006 0.005 386.170 0.005 0.000 0.000 0.000 2.476 2.487 5.083 195.200 32.000 0.006 0.060 0.006 0.005 503.633 0.005 0.000 0.000 0.000 2.943 2.954 5.125 196.800 33.600 0.006 0.060 0.006 0.005 648.040 0.005 0.000 0.000 0.000 3.436 3.447 5.167 198.400 35.200 0.006 0.060 0.006 0.005 823.773 0.005 0.000 0.000 0.000 3.953 3.964 5.208 199.987 36.787 0.006 0.060 0.006 0.005 1033.814 0.005 0.000 0.000 0.000 4.490 4.501 ATTACHMENT 5 Drawdown Time Calculations Project Name…….Church Residence Project No………….575-01 Date…………………..9/1/2019 Drawdown Calculation for IMP 1 Total Drawdown Time:146.2 hours Note: Surface Depth (ft)Volume (cu-ft)Qorifice (cfs)∆T (hr)Total Time (hr) 5.20 1664 4.395 0.000 0.0 4.395 5.10 1632 3.148 0.002 0.0 3.148 5.00 1600 2.048 0.003 0.0 2.048 4.90 1568 1.119 0.006 0.0 1.119 4.80 1536 0.402 0.012 0.0 0.402 4.70 1504 0.009 0.043 0.1 0.009 4.60 1472 0.009 0.988 1.1 0.009 4.50 1440 0.008 1.049 2.1 0.008 4.40 1408 0.008 1.132 3.2 0.008 4.30 1376 0.007 1.268 4.5 0.007 4.20 1344 0.005 1.490 6.0 0.005 4.10 1312 0.005 1.649 7.6 0.005 4.00 1280 0.005 1.669 9.3 0.005 3.90 1248 0.005 1.690 11.0 0.005 3.80 1216 0.005 1.712 12.7 0.005 3.70 1184 0.005 1.735 14.5 0.005 3.60 1152 0.005 1.759 16.2 0.005 3.50 1120 0.005 1.784 18.0 0.005 3.40 1088 0.005 1.809 19.8 0.005 3.30 1056 0.005 1.836 21.6 0.005 3.20 1024 0.005 1.864 23.5 0.005 3.10 992 0.005 1.894 25.4 0.005 3.00 960 0.005 1.925 27.3 0.005 2.90 928 0.005 1.957 29.3 0.005 2.80 896 0.004 1.991 31.3 0.004 2.70 864 0.004 2.028 33.3 0.004 2.60 832 0.004 2.066 35.4 0.004 2.50 800 0.004 2.106 37.5 0.004 2.40 768 0.004 2.149 39.6 0.004 2.30 736 0.004 2.194 41.8 0.004 2.20 704 0.004 2.243 44.1 0.004 2.10 672 0.004 2.295 46.3 0.004 2.00 640 0.004 2.350 48.7 0.004 1.90 608 0.004 2.410 51.1 0.004 1.80 576 0.004 2.475 53.6 0.004 1.70 544 0.003 2.545 56.1 0.003 1.60 512 0.003 2.622 58.8 0.003 1.50 480 0.003 2.706 61.5 0.003 1.40 448 0.003 2.799 64.3 0.003 1.30 416 0.003 2.901 67.2 0.003 1.20 384 0.003 3.016 70.2 0.003 1.10 352 0.003 3.146 73.3 0.003 1.00 320 0.003 3.295 76.6 0.003 0.90 288 0.002 3.466 80.1 0.002 0.80 256 0.002 3.668 83.7 0.002 0.70 224 0.002 3.909 87.7 0.002 0.60 192 0.002 4.206 91.9 0.002 0.50 160 0.002 4.582 96.4 0.002 0.40 128 0.002 5.082 101.5 0.002 Though drowdown time exceeds the 96 hour requirement for vector control, a vector control plan is not recommended, as the detention system is entirely underground, and is not susceptible to typical vector control issues. TORY R. WALKER ENGINEERING RELIABLE SOLUTIONS IN WATER RESOURCES Surface Depth (ft)Volume (cu-ft)Qorifice (cfs)∆T (hr)Total Time (hr) 0.30 96 0.001 5.794 107.3 0.001 0.20 64 0.001 6.929 114.3 0.001 0.10 32 0.001 9.223 123.5 0.001 0.00 0 0.000 22.746 146.2 0.000---1 -I I- ATTACHMENT 6 Pre-Developed and Post-Project DMA Exhibits Da t e : 1 0 / 1 / 2 0 1 9 - L a s t s a v e d b y : R o b i n - P a t h : X : \ P r o j e c t s 2 \ 5 7 5 ( B a r r y a n d S h a n n a C h u r c h ) \ 0 1 - C h u r c h R e s i d e n c e \ 0 5 G I S \ M a p D o c s \ A t t 6 a - V i c i n i t y M a p . m x d Project Vicinity Map Church Residence Carlsbad, California §¨¦5 ± CARLSBAD VISTA OCEANSIDE S.D. COUNTY SAN MARCOS ENCINITAS ESCONDIDO SAN DIEGO Church Residence Project Site 1 in = 750 ft Agua Hedionda Tamara c k A v e Vicinity -TRWE - Da t e : 1 0 / 1 / 2 0 1 9 - L a s t s a v e d b y : R o b i n - P a t h : X : \ P r o j e c t s 2 \ 5 7 5 ( B a r r y a n d S h a n n a C h u r c h ) \ 0 1 - C h u r c h R e s i d e n c e \ 0 5 G I S \ M a p D o c s \ A t t 6 b - E x i s t i n g D M A E x h i b i t . m x d Existing Condition DMA Map Church Residence DMA 1 ±1 in = 25 ft 0.245 Acres POC-1 Adams St -TRWE - Da t e : 1 0 / 1 / 2 0 1 9 - L a s t s a v e d b y : R o b i n - P a t h : X : \ P r o j e c t s 2 \ 5 7 5 ( B a r r y a n d S h a n n a C h u r c h ) \ 0 1 - C h u r c h R e s i d e n c e \ 0 5 G I S \ M a p D o c s \ A t t 6 c - P r o p o s e d _ D M A _ E x h i b i t . m x d Proposed Condition DMA Map Church Residence 0.236 Acres POC-1 0.002 Acres (67 SF) BY-PASS 1-1 N.T.S. DMA 1-1 DMA 1-1 Imp (ft2)Perv (ft2)Total (ft2) DMA 2 1496 224 1720 IMP 2 0 40 40 DMA 3 3689 810 4499 IMP 3 0 103 103 DMA 4 551 0 551 DMA 5 750 39 789 IMP 5 0 36 36 DMA 6 1376 43 1419 IMP 6 0 42 42 DMA 7 288 15 303 IMP 7 0 15 15 DMA 9 370 46 416 IMP 9 0 44 44 IMP 10 0 246 246 Total 8521 1702 10223 0.236 AC Self Mitigating Vault -TRWE- BAS/N 3 A3 = 4,419 SF = 0.103 AC C3 = 0.78 l,a0 = 6.59 "'/HR Q100 = 0. 53 CFS BA SIN 2 A2 = 1,720 SF = 0.039 AC C2 = 0.80 fwo = 6.59 IN/HI, Q100 = 0. 21 CFS JUNC TION I 0100 = 0. 74 CFS BASIN 4 A4 = 551 SF= 0.013 AC C4 = 0.90 f,00 = 6.59 IN!i'R \ 0100 = 0.07 :":FS \ I Of MiN!tvtUS . BASIN 5 / A5 = 789 SF = 0.018 AC C5 = 0.90 l100 = 6.59 111/f/R 0100 = 0.11 crs =BA-'-"'S"'-'IN'-'6"---___ II A = 67 SF= 0002 ~C i A6 = 1,419 SF = O.OJJ AC ·:":5 = 0.90 _IIOC = 6.59 IN /HF/ ·'Jioa = 0. 19 CFS ! BASIN 7 A7 = 303 SF = 0.001 AC BASIN g C, = 0.90 ~'--'='-'---''--S-F ---0-0-10-A~C -"-9 IN I A9 = 416 -. l100 -6.1/ , HR Cg = 0.90 0100 = 0. 'J4 CFS I _ 6 59 IN/ 100 -· HR Q100 = 0. 06 CFS JUNCTION 2 A8 = 380 SF = 0.009 AC C8 = 0.00 1100 = 6.59 INIHR Q100 = 0. 00 CFS ATTACHMENT 7 NRCS Soils Map 33' 8' 54''N 33° 8' 32" N s: ~ ~ 11--;:1 Hydrologic Soil Group-San Diego County Area, California ~ § ~- I i i I s: ~ ~ t N A 469200 469300 469400 I ~,~ 469300 469400 Map Scale: 1:4,740 if printed on A landscape (11" x 8.5") sheet 469500 469500 ---====-------=======Meters 0 so 100 200 300 11©:W ----=====--------========Feet 0 200 400 800 1200 469600 469600 Map projection: Web Mercator OlmerO'..lOrdinates: WGS84 Edge tics: 1.111'1 Zone llN WGS84 469700 469700 USDA Natural Resources Web Soil Survey National Cooperative Soil Survey riF Conservation Service 469800 469800 469900 469900 470000 470100 470100 s: ~ ~ t s: ~ ~ 8 I i i i ; I 1/23/2014 Page 1 of 4 33' 8' 54' N 33° 8' 32" N Hydrologic Soil Group-San Diego County Area, California MAP LEGEND MAP INFORMATION Area of Interest (AOI) D Area of Interest (AOI) Soils Soll Rating Polygons 0 A 0 A/0 08 0 8/0 □c 0 CID □o D Not rated or not available Soil Rating Lines A ,.,,, ND ....,,,. 8 BID ,. " C CID D ,. " Not rated or not available Soll Rating Points □ A □ ND 8 8/0 USDA Natural Resources ~-a Conservation Service □ C □ CID D □ Not rated or not available Water Features Streams and Canals Transportation t-H Rails _,,, Interstate Highways ..,..; US Routes Major Roads Local Roads Background • Aerial Photography Web Soil Survey National Cooperative Soil Survey 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: http://websoilsurvey.nrcs.usda.gov Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, wh ich 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: Survey Area Data: San Diego County Area, California Version 7, Nov 15, 2013 Soil map units are labeled (as space allows) for map scales 1 :50,000 or larger. Date(s) aerial images were photographed: May 3,2010-Jun 19, 2010 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. 1/23/2014 Page 2 of 4 Hydrologic Soil Group-San Diego County Area, California Hydrologic Soil Group Hydrologic Soil Group-Summary by Map Unit -San Diego County Area, California (CA638) Map unit symbol Map unit name Rating CbC Carlsbad gravelly loamy B sand, 5 to 9 percent slopes CbD Carlsbad gravelly loamy B sand, 9 to 15 percent slopes I- GaF Gaviota fine sandy loam, D 30 to 50 percent slopes LfC Las Flores-Urban land D complex, 2 to 9 percent slopes --- LG-W Lagoon water LvF3 Loamy alluvial land-D Huerhuero complex, 9 to 50 percent slopes, severely eroded MIE Marina loamy coarse B sand, 9 to 30 percent slopes Totals for Area of Interest USDA Natural Resources ~1Eii Conservation Service Web Soil Survey National Cooperative Soil Survey Acres in AOI Percent of AOI 5.7 5.4% 7.4 7.0% 11 .6 11.0% 18.6 17.6% 30.4 28.9% 4.3 4.1% 27.3 26.0% 105.2 100.0% 1/23/2014 Page 3 of 4 Hydrologic Soil Group-San Diego County Area, California 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 (AID, BID , 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 (AID, B/D, or CID), 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. Rating Options Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher USDA Natural Resources =-fiiii Conservation Service Web Soil Survey National Cooperative Soil Survey 1/23/2014 Page 4 of 4 ATTACHMENT 8 SWMM Input Data PRE_DEV_POC-1.inp [TITLE] ;;Project Title/Notes 575-01 Church Residence: Pre-Developed Condition (Oceanside RG) [OPTIONS] ;;Option Value FLOW_UNITS CFS INFILTRATION GREEN_AMPT FLOW_ROUTING KINWAVE LINK_OFFSETS DEPTH MIN_SLOPE 0 ALLOW_PONDING NO SKIP_STEADY_STATE NO START_DATE 08/28/1951 START_TIME 05:00:00 REPORT_START_DATE 08/28/1951 REPORT_START_TIME 05:00:00 END_DATE 05/23/2008 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 INERTIAL_DAMPING PARTIAL NORMAL_FLOW_LIMITED BOTH FORCE_MAIN_EQUATION H-W VARIABLE_STEP 0.75 LENGTHENING_STEP 0 MIN_SURFAREA 0 MAX_TRIALS 0 HEAD_TOLERANCE 0 SYS_FLOW_TOL 5 LAT_FLOW_TOL 5 MINIMUM_STEP 0.5 THREADS 1 [EVAPORATION] ;;Data Source Parameters ;;-------------- ---------------- MONTHLY 0.030 0.050 0.080 0.110 0.130 0.150 0.150 0.130 0.110 0.080 0.040 0.020 DRY_ONLY NO [RAINGAGES] ;;Name Format Interval SCF Source ;;-------------- --------- ------ ------ ---------- OCEANSIDE INTENSITY 1:00 1.0 TIMESERIES OCEANSIDE Page 1 PRE_DEV_POC-1.inp [SUBCATCHMENTS] ;;Name Rain Gage Outlet Area %Imperv Width %Slope CurbLen SnowPack ;;-------------- ---------------- ---------------- -------- -------- -------- -------- -------- ---------------- DMA_1 OCEANSIDE POC-1 0.245 0 69 25 0 [SUBAREAS] ;;Subcatchment N-Imperv N-Perv S-Imperv S-Perv PctZero RouteTo PctRouted ;;-------------- ---------- ---------- ---------- ---------- ---------- ---------- ---------- DMA_1 0.012 .06 0.05 0.1 25 OUTLET [INFILTRATION] ;;Subcatchment Suction Ksat IMD ;;-------------- ---------- ---------- ---------- DMA_1 3 0.2 0.32 [OUTFALLS] ;;Name Elevation Type Stage Data Gated Route To ;;-------------- ---------- ---------- ---------------- -------- ---------------- POC-1 0 FREE NO [TIMESERIES] ;;Name Date Time Value ;;-------------- ---------- ---------- ---------- OCEANSIDE FILE "X:\ENGR\HMP\SWMM\Rain Gages\Oceanside\Oside_HOURLY.prn" [REPORT] ;;Reporting Options INPUT NO CONTROLS NO SUBCATCHMENTS ALL NODES ALL LINKS ALL [TAGS] [MAP] DIMENSIONS 2182.681359 6021.851375 2183.279716 6040.229030 Units Degrees [COORDINATES] ;;Node X-Coord Y-Coord ;;-------------- ------------------ ------------------ POC-1 2182.903000 6028.978143 [VERTICES] ;;Link X-Coord Y-Coord ;;-------------- ------------------ ------------------ Page 2 PRE_DEV_POC-1.inp [Polygons] ;;Subcatchment X-Coord Y-Coord ;;-------------- ------------------ ------------------ DMA_1 2182.902773 6036.961572 [SYMBOLS] ;;Gage X-Coord Y-Coord ;;-------------- ------------------ ------------------ OCEANSIDE 2182.903000 6039.000000 Page 3 POST_DEV_POC-1.inp [TITLE] ;;Project Title/Notes 575-01 Church Residence: Post-Developed Condition (Oceanside RG) [OPTIONS] ;;Option Value FLOW_UNITS CFS INFILTRATION GREEN_AMPT FLOW_ROUTING KINWAVE LINK_OFFSETS DEPTH MIN_SLOPE 0 ALLOW_PONDING NO SKIP_STEADY_STATE NO START_DATE 08/28/1951 START_TIME 05:00:00 REPORT_START_DATE 08/28/1951 REPORT_START_TIME 05:00:00 END_DATE 05/23/2008 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 INERTIAL_DAMPING PARTIAL NORMAL_FLOW_LIMITED BOTH FORCE_MAIN_EQUATION H-W VARIABLE_STEP 0.75 LENGTHENING_STEP 0 MIN_SURFAREA 0 MAX_TRIALS 0 HEAD_TOLERANCE 0 SYS_FLOW_TOL 5 LAT_FLOW_TOL 5 MINIMUM_STEP 0.5 THREADS 1 [EVAPORATION] ;;Data Source Parameters ;;-------------- ---------------- MONTHLY 0.030 0.050 0.080 0.110 0.130 0.150 0.150 0.130 0.110 0.080 0.040 0.020 DRY_ONLY NO [RAINGAGES] ;;Name Format Interval SCF Source ;;-------------- --------- ------ ------ ---------- OCEANSIDE INTENSITY 1:00 1.0 TIMESERIES OCEANSIDE Page 1 POST_DEV_POC-1.inp [SUBCATCHMENTS] ;;Name Rain Gage Outlet Area %Imperv Width %Slope CurbLen SnowPack ;;-------------- ---------------- ---------------- -------- -------- -------- -------- -------- ---------------- DMA_1-1 OCEANSIDE STOR_1-1 .235 83.3 292 10 0 BY-PASS_1-1 OCEANSIDE POC-1 .0015 100 8 0 0 [SUBAREAS] ;;Subcatchment N-Imperv N-Perv S-Imperv S-Perv PctZero RouteTo PctRouted ;;-------------- ---------- ---------- ---------- ---------- ---------- ---------- ---------- DMA_1-1 0.012 .08 0.05 0.1 25 OUTLET BY-PASS_1-1 0.012 .08 0.05 0.1 25 OUTLET [INFILTRATION] ;;Subcatchment Suction Ksat IMD ;;-------------- ---------- ---------- ---------- DMA_1-1 3 .2 .32 BY-PASS_1-1 3 .2 .32 [OUTFALLS] ;;Name Elevation Type Stage Data Gated Route To ;;-------------- ---------- ---------- ---------------- -------- ---------------- POC-1 0 FREE NO [STORAGE] ;;Name Elev. MaxDepth InitDepth Shape Curve Name/Params N/A Fevap Psi Ksat IMD ;;-------------- -------- ---------- ----------- ---------- ---------------------------- -------- -------- -------- -------- STOR_1-1 0 5.2 0 TABULAR STOR_1 0 0 [OUTLETS] ;;Name From Node To Node Offset Type QTable/Qcoeff Qexpon Gated ;;-------------- ---------------- ---------------- ---------- --------------- ---------------- ---------- -------- 1 STOR_1-1 POC-1 0 TABULAR/DEPTH OUT_1 NO [CURVES] ;;Name Type X-Value Y-Value ;;-------------- ---------- ---------- ---------- OUT_1 Rating 0.000 0.0000 OUT_1 0.042 0.0004 OUT_1 0.083 0.0007 OUT_1 0.125 0.001 Page 2 POST_DEV_POC-1.inp OUT_1 0.167 0.001 OUT_1 0.208 0.001 OUT_1 0.250 0.001 OUT_1 0.292 0.001 OUT_1 0.333 0.001 OUT_1 0.375 0.002 OUT_1 0.417 0.002 OUT_1 0.458 0.002 OUT_1 0.500 0.002 OUT_1 0.542 0.002 OUT_1 0.583 0.002 OUT_1 0.625 0.002 OUT_1 0.667 0.002 OUT_1 0.708 0.002 OUT_1 0.750 0.002 OUT_1 0.792 0.002 OUT_1 0.833 0.002 OUT_1 0.875 0.002 OUT_1 0.917 0.003 OUT_1 0.958 0.003 OUT_1 1.000 0.003 OUT_1 1.042 0.003 OUT_1 1.083 0.003 OUT_1 1.125 0.003 OUT_1 1.167 0.003 OUT_1 1.208 0.003 OUT_1 1.250 0.003 OUT_1 1.292 0.003 OUT_1 1.333 0.003 OUT_1 1.375 0.003 OUT_1 1.417 0.003 OUT_1 1.458 0.003 OUT_1 1.500 0.003 OUT_1 1.542 0.003 OUT_1 1.583 0.003 OUT_1 1.625 0.003 OUT_1 1.667 0.003 OUT_1 1.708 0.003 OUT_1 1.750 0.003 OUT_1 1.792 0.004 OUT_1 1.833 0.004 OUT_1 1.875 0.004 OUT_1 1.917 0.004 OUT_1 1.958 0.004 OUT_1 2.000 0.004 OUT_1 2.042 0.004 OUT_1 2.083 0.004 OUT_1 2.125 0.004 OUT_1 2.167 0.004 OUT_1 2.208 0.004 OUT_1 2.250 0.004 Page 3 POST_DEV_POC-1.inp OUT_1 2.292 0.004 OUT_1 2.333 0.004 OUT_1 2.375 0.004 OUT_1 2.417 0.004 OUT_1 2.458 0.004 OUT_1 2.500 0.004 OUT_1 2.542 0.004 OUT_1 2.583 0.004 OUT_1 2.625 0.004 OUT_1 2.667 0.004 OUT_1 2.708 0.004 OUT_1 2.750 0.004 OUT_1 2.792 0.004 OUT_1 2.833 0.004 OUT_1 2.875 0.004 OUT_1 2.917 0.005 OUT_1 2.958 0.005 OUT_1 3.000 0.005 OUT_1 3.042 0.005 OUT_1 3.083 0.005 OUT_1 3.125 0.005 OUT_1 3.167 0.005 OUT_1 3.208 0.005 OUT_1 3.250 0.005 OUT_1 3.292 0.005 OUT_1 3.333 0.005 OUT_1 3.375 0.005 OUT_1 3.417 0.005 OUT_1 3.458 0.005 OUT_1 3.500 0.005 OUT_1 3.542 0.005 OUT_1 3.583 0.005 OUT_1 3.625 0.005 OUT_1 3.667 0.005 OUT_1 3.708 0.005 OUT_1 3.750 0.005 OUT_1 3.792 0.005 OUT_1 3.833 0.005 OUT_1 3.875 0.005 OUT_1 3.917 0.005 OUT_1 3.958 0.005 OUT_1 4.000 0.005 OUT_1 4.042 0.005 OUT_1 4.083 0.005 OUT_1 4.125 0.005 OUT_1 4.167 0.005 OUT_1 4.208 0.005 OUT_1 4.250 0.005 OUT_1 4.292 0.006 OUT_1 4.333 0.007 OUT_1 4.375 0.007 Page 4 POST_DEV_POC-1.inp OUT_1 4.417 0.008 OUT_1 4.458 0.008 OUT_1 4.500 0.008 OUT_1 4.542 0.008 OUT_1 4.583 0.009 OUT_1 4.625 0.009 OUT_1 4.667 0.009 OUT_1 4.708 0.019 OUT_1 4.750 0.148 OUT_1 4.792 0.354 OUT_1 4.833 0.614 OUT_1 4.875 0.918 OUT_1 4.917 1.261 OUT_1 4.958 1.638 OUT_1 5.000 2.048 OUT_1 5.042 2.487 OUT_1 5.083 2.954 OUT_1 5.125 3.447 OUT_1 5.167 3.964 OUT_1 5.208 4.501 ; STOR_1 Storage 0 320 STOR_1 5.2 320 [TIMESERIES] ;;Name Date Time Value ;;-------------- ---------- ---------- ---------- OCEANSIDE FILE "X:\ENGR\HMP\SWMM\Rain Gages\Oceanside\Oside_HOURLY.prn" [REPORT] ;;Reporting Options INPUT NO CONTROLS NO SUBCATCHMENTS ALL NODES ALL LINKS ALL [TAGS] [MAP] DIMENSIONS 191.920 4920.830 1021.827 5718.627 Units None [COORDINATES] ;;Node X-Coord Y-Coord ;;-------------- ------------------ ------------------ POC-1 597.451 5027.622 STOR_1-1 597.451 5362.131 [VERTICES] ;;Link X-Coord Y-Coord Page 5 POST_DEV_POC-1.inp ;;-------------- ------------------ ------------------ [Polygons] ;;Subcatchment X-Coord Y-Coord ;;-------------- ------------------ ------------------ DMA_1-1 597.451 5525.460 DMA_1-1 597.451 5525.460 BY-PASS_1-1 749.786 5362.131 BY-PASS_1-1 749.786 5362.131 BY-PASS_1-1 749.786 5362.131 BY-PASS_1-1 749.786 5362.131 BY-PASS_1-1 749.786 5362.131 [SYMBOLS] ;;Gage X-Coord Y-Coord ;;-------------- ------------------ ------------------ OCEANSIDE 597.451 5629.110 Page 6 ATTACHMENT 9 SWMM Summary Report PRE_DEV_POC-1.rpt EPA STORM WATER MANAGEMENT MODEL - VERSION 5.1 (Build 5.1.012) -------------------------------------------------------------- 575-01 Church Residence: Pre-Developed Condition (Oceanside RG) ********************************************************* 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 RDII ................... NO Snowmelt ............... NO Groundwater ............ NO Flow Routing ........... NO Water Quality .......... NO Infiltration Method ...... GREEN_AMPT Starting Date ............ 08/28/1951 05:00:00 Ending Date .............. 05/23/2008 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 ...... 13.786 675.250 Evaporation Loss ......... 0.025 1.203 Infiltration Loss ........ 13.320 652.428 Surface Runoff ........... 0.493 24.163 Final Storage ............ 0.000 0.000 Continuity Error (%) ..... -0.377 ************************** Volume Volume Flow Routing Continuity acre-feet 10^6 gal ************************** --------- --------- Dry Weather Inflow ....... 0.000 0.000 Wet Weather Inflow ....... 0.493 0.161 Groundwater Inflow ....... 0.000 0.000 RDII Inflow .............. 0.000 0.000 Page 1 PRE_DEV_POC-1.rpt External Inflow .......... 0.000 0.000 External Outflow ......... 0.493 0.161 Flooding Loss ............ 0.000 0.000 Evaporation Loss ......... 0.000 0.000 Exfiltration Loss ........ 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_1 675.25 0.00 1.20 652.43 24.16 0.16 0.25 0.036 Analysis begun on: Wed Sep 25 13:31:11 2019 Analysis ended on: Wed Sep 25 13:31:29 2019 Total elapsed time: 00:00:18 Page 2 EPA STORM WATER MANAGEMENT MODEL - VERSION 5.1 (Build 5.1.010) -------------------------------------------------------------- 439-01 Martin Residence- Post Development Condition Model ********************************************************* 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 RDII ................... NO Snowmelt ............... NO Groundwater ............ NO Flow Routing ........... YES Ponding Allowed ........ NO Water Quality .......... NO Infiltration Method ...... GREEN_AMPT Flow Routing Method ...... KINWAVE Starting Date ............ AUG-28-1951 05:00:00 Ending Date .............. MAY-23-2008 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 ...... 10.455 675.250 Evaporation Loss ......... 1.043 67.382 Infiltration Loss ........ 1.528 98.698 Surface Runoff ........... 8.102 523.261 Final Storage ............ 0.001 0.032 Post-Dev Output (POC-1) SWMM 5.1 Page 1 Continuity Error (%) ..... -2.092 ************************** Volume Volume Flow Routing Continuity acre-feet 10^6 gal ************************** --------- --------- Dry Weather Inflow ....... 0.000 0.000 Wet Weather Inflow ....... 8.102 2.640 Groundwater Inflow ....... 0.000 0.000 RDII Inflow .............. 0.000 0.000 External Inflow .......... 0.000 0.000 External Outflow ......... 8.101 2.640 Flooding Loss ............ 0.000 0.000 Evaporation Loss ......... 0.000 0.000 Exfiltration Loss ........ 0.000 0.000 Initial Stored Volume .... 0.000 0.000 Final Stored Volume ...... 0.000 0.000 Continuity Error (%) ..... 0.010 ******************************** Highest Flow Instability Indexes ******************************** All links are stable. ************************* Routing Time Step Summary ************************* Minimum Time Step : 60.00 sec Average Time Step : 60.00 sec Maximum Time Step : 60.00 sec Percent in Steady State : 0.00 Average Iterations per Step : 1.00 Percent Not Converging : 0.00 *************************** Subcatchment Runoff Summary *************************** -------------------------------------------------------------------------------------------------------- Total Total Total Total Total Total Peak Runoff Post-Dev Output (POC-1) SWMM 5.1 Page 2 Precip Runon Evap Infil Runoff Runoff Runoff Coeff Subcatchment in in in in in 10^6 gal CFS -------------------------------------------------------------------------------------------------------- DMA_1-1 675.25 0.00 65.41 99.02 524.96 2.64 0.22 0.777 BY-PASS_1-1 675.25 0.00 674.69 0.00 0.00 0.00 0.00 0.000 ****************** Node Depth Summary ****************** --------------------------------------------------------------------------------- Average Maximum Maximum Time of Max Reported Depth Depth HGL Occurrence Max Depth Node Type Feet Feet Feet days hr:min Feet --------------------------------------------------------------------------------- POC-1 OUTFALL 0.00 0.00 0.00 0 00:00 0.00 STOR_1-1 STORAGE 0.07 3.82 3.82 18857 11:50 3.82 ******************* Node Inflow Summary ******************* ------------------------------------------------------------------------------------------------- Maximum Maximum Lateral Total Flow Lateral Total Time of Max Inflow Inflow Balance Inflow Inflow Occurrence Volume Volume Error Node Type CFS CFS days hr:min 10^6 gal 10^6 gal Percent ------------------------------------------------------------------------------------------------- POC-1 OUTFALL 0.00 0.22 18857 11:50 0 2.64 0.000 STOR_1-1 STORAGE 0.22 0.22 18857 12:01 2.64 2.64 0.010 ********************** Node Surcharge Summary ********************** 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 Post-Dev Output (POC-1) SWMM 5.1 Page 3 --------------------------------------------------------------------- STOR_1-1 STORAGE 497370.00 3.816 0.184 ********************* Node Flooding Summary ********************* No nodes were flooded. ********************** Storage Volume Summary ********************** -------------------------------------------------------------------------------------------------- Average Avg Evap Exfil Maximum Max Time of Max Maximum Volume Pcnt Pcnt Pcnt Volume Pcnt Occurrence Outflow Storage Unit 1000 ft3 Full Loss Loss 1000 ft3 Full days hr:min CFS -------------------------------------------------------------------------------------------------- STOR_1-1 0.023 2 0 0 1.279 95 18857 11:49 0.22 *********************** Outfall Loading Summary *********************** ----------------------------------------------------------- Flow Avg Max Total Freq Flow Flow Volume Outfall Node Pcnt CFS CFS 10^6 gal ----------------------------------------------------------- POC-1 9.44 0.00 0.22 2.640 ----------------------------------------------------------- System 9.44 0.00 0.22 2.640 ******************** Link Flow Summary ******************** ----------------------------------------------------------------------------- Maximum Time of Max Maximum Max/ Max/ Post-Dev Output (POC-1) SWMM 5.1 Page 4 |Flow| Occurrence |Veloc| Full Full Link Type CFS days hr:min ft/sec Flow Depth ----------------------------------------------------------------------------- 1 DUMMY 0.22 18857 11:50 ************************* Conduit Surcharge Summary ************************* No conduits were surcharged. Analysis begun on: Thu Nov 17 14:17:55 2016 Analysis ended on: Thu Nov 17 14:18:21 2016 Total elapsed time: 00:00:26 Post-Dev Output (POC-1) SWMM 5.1 Page 5 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 Typical Maintenance Indicator(s) for Vegetated BMPs Maintenance Actions 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 flow Repair and adjust the irrigation system 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 walls or outlet structures Repair or replace as applicable Typical Maintenance Indicator(s) for Detention Vaults Maintenance Actions Accumulation of sediment, litter, or debris Remove & properly dispose of accumulated materials Obstructed inlet or outlet structure Clear obstructions Damage to structural components such as wiers, inlet or outlet structures Repair or replace as applicable Though drowdown time exceeds the 96 hour requirement for vector control, a vector control plan is not recommended, as the detention system is entirely underground, and is not susceptible to typical vector control issues. BMP Maintenance Plan The structural BMP Maintenance Plan is in accordance with Category 1 requirements with minimal maintenance responsibilities on a single family residential project. The property owner is responsible to ensure inspection, operation, and maintenance of the structural BM P. 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 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 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. Hand tools and manual labor will be used to perform maintenance on the biofiltration basins and detention vault. Frequency Quarterly to provide 6" from top of grate to soil Quarterly Quarterly Quarterly Quarterly Quarterly Quarterly as Frequency Quarterly Quarterly Quarterly ATTACHMENT 4 City standard Single Sheet BMP (SSBMP) Exhibit [Use the City’s standard Single Sheet BMP Plan.] ENGINEERING DEPARTMENT N 1 0: '-" or! ~ e, -3s --" !: "' 6 ~ e, -j "- E; e "' "" ·" 8" J ~ ~ ! §! ,_ ... I • I • I - • • I I a I I I 0 I I I I I I I I 1 \ I I I I I .. -._ -.._ I ' I BMP ID# I I I/ BMP TYPE SOURCE CONmOL CD--@) ROOF DRAIN TO LANDSCAPING EFFICIENT /RR/GA TION SY.S'TEMS TREATMENT CONTROL ®--@ BIOFIL TRA TION BASIN HYDROMODIFICA TION @ DRY VAULT SYMBOL • ~ ... ·I ~ LOW IMPACT DESIGN (L.I.D.) CONSERVATION OF NATURAL DRAINAGES, WfLL DRAINED SOILS ANO S/GNIRCANT VEGETATION MINIMIZE DISTURBANCE TO NATURAL DRAINAGES MINIMIZE SOIL COMPACTION @--@ PERVIOUS PAVEMENTS I' ,;,., .. ,, .. '. ··1 :-:·\:::·:~·::\~.< • CASQA NO. S0-11 S0-12 TC-32 MP-50 uo 2.2.1 UD 2.2.2 LID 2.2.4 LID J.2 SD-12 BMP TABLE QUANTITY DRAWING NO. SHEET NO.(S) 10 EA -3, 4 3, 4 289 SF -3, 4 373 SF -4 4 4 4 300 SF -3 INSPECTION MAINTENANCE FREQUENCY FREQUENCY ANNUALLY ANNUALLY QUARTERLY SEMI-ANNUALLY QUARTERLY SEMI-ANNUALLY SCALE: 1"=10' .4 I SOURCE CONTROL BMPs ISC-1 I PREVENTION OF /UICIT DISCHARGES INTO THE MS4 (OWNER £DUCA TION) PROTECT MATERIALS STORm IN OUTDOOR WORK AREAS ISC-5 I FROM RAINFALL, RUN-ON, RUNOFF AND WIND DISPERSAL I I I I I I I I I I I I I I I I I I I I ISC-6 I NEED FOR FUTURE INDOOR OUTDOOR &: STRUCTURAL PEST CONTROL (OWNER £DUCA TION) PARTY RESPONSIBLE FOR MAINTENANCE: BARRY CHURCH LANDSCAPE/OUTDOOR PESTICIDE USE (OWNER £DUCA TION) POOLS, SPAS, PONDS, DECORATIVE FOUNTAINS ANO OTHER WATER FEATURES EASEMENT NQTfS: 621 POLARIS DRIVE ENCINITAS, CA 92024 MISCEUANEOUS DRAIN OR WASH WATER (NO COPPER ON ROOF) SITE DESIGN BMPs ISO-I I MAINTAIN NATURAL DRAINAGE PATHWAY.5 AND HYDROLOGIC FEATURES ISD-2 I CONSERVE NATURAL AREAS, SOILS AND VEGETATION ISD-3 I MINIMIZE IMPERVIOUS AREA (MUL Tl-STORY BUILDING) ISD-4 I MINIMIZE SOIL COMPACTION ISD-5 I IMPERVIOUS AREA DISPERSION ISD-6 I RUNOFF COLLECTION ISD-71 LANDSCAPING WITH NATIVE OR DROUGHT TOLERANT SPECIES ISD-721 IMPLEMENTATION OF EFRCIENT !RR/GA TION SY.S'TEMS I TC-321 BIOFIL TRA TION BMP NOTES: 1. THESE BMPS ARE MANDA TORY TO BE INSTALLED PER MANUFACTURER'S RECOMMENDATIONS OR THESE PLANS. 2. NO CHANGES TO THE PROPOSED BMPS ON THIS SHEET WITHOUT PRIOR APPROVAL FROM THE CITY ENGINEER. 3. NO SUBSTITUTIONS TO THE MATERIAL OR TYPES OR PLANTING TYPES WITHOUT PRIOR APPROVAL FROM THE CITY ENGINEER. 4. NO OCCUPANCY WILL BE GRANTED UNTIL THE CITY INSPECTION STAFF HAS INSPECTED THIS PROJECT FOR APPROPR/A TE BMP CONSTRUCTION AND INSTALLATION. 5. REFER TO MAINTENANCE AGREEMENT DOCUMENT. 6. SEE PROJECT SWQMP FOR ADDITIONAL INFORMATION. & AN EASEMENT FOR SEWfR PIPEUNE AND INCIDENTAL PURPOSES RECORDED MARCH 5, 1964 AS INSTRUMENT No. 41721 OF OFFICIAL RECORDS. ~ AN EASEMENT FOR SEWfR PIPEUNE AND INCIDENTAL PURPOSES RECORDED DECEMBER 7, 2007 AS INSTRUMENT No. 07-761180 OF OFFICIAL RECORDS. /0,. PROPOSED 5 FOOT EASEMENT OED/CATION TO THE CITY OF CARLSBAD. /i:,. MEAN HIGH TIDE LINE (ELEVATION 2.25} ~ LIMIT OF 100' WfTLAND BUFFER. ~ UMIT OF PROPOSED 25' LATERAL ACCESS EASEMENT * Exp. 6/30/22 * PLJ,N PREPARED B~~ RANDY R. BROWN SOWARDS AND BROWN ENGINEERING, INC 2187 NEWCASTLE A VENUE, STE 103 CARDIFF BY THE SEA, CA 92007 (760) 436-8500 JOB NO. 18-045 8/18/20 • SOWARDS & BROWN ENGINEERING • CONSULTING ENGINEERS 2187 NEWCASTLE AVENUE SUITE 103 CARDIFF BY THE SEA, CA., 92007 TEL. 760/436-8500 FAX 760/436-8603 f---f----+-----------l---f-----l------+---1 LLI I CITY OF CARLSBAD I I~ 1------1---+--------------------l------l-----l-----l----l GRADING PLANS FOR: CHURCH RESIDENCE GR2020-0015 SINGLE SHfil BMP SITE PLAN DEV2019-0036 l------l---+-------------------+-----+----l-----1----1 RECORD COPY PROJECT NO. PD2020-0008 ~ 1f DATE INITIAL DATE INITIAL DATE INITIAL I DRAWING NO. I ! ~~~~~~~~~~~~!"""!~~!"!!'!"~------------------------------------------------------------------------------.!;EN;G;IN;EE;R;O;F;WO;;R;K ;;;;;;;R;E;V;l;S;IO;N;;D;E;S;C;R;l;P;T;IO;N;;;;;;;;;;;OTH;;ER;A;P;P;RO;VA;L;;;C;IT;Y;A;P;PR;O;VA;L~;;;;;l;Nl;TIA;L;;;;;;;;;;D;ATE;;;;;;;;;;5;2;;4;-;;6;;A;;;;~ D. \DRA'MNG F'IL.ES\TITI...E SHEETS\GRADING TITLE SI-IEET.DWG REVISED. 02/15/17