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HomeMy WebLinkAboutCDP 2020-0017; SAREM RESIDENCE; PRIORITY DEVELOPMENT PROJECT (PDP) STORM WATER QUALITY MANAGEMENT PLAN (SWQMP); 2021-07-23CITY OF CARLSBAD PRIORITY DEVELOPMENT PROJECT (PDP) STORM WATER QUALITY MANAGEMENT PLAN (SWQMP) FOR SAREM RESIDENCE 4005 SKYLINE ROAD PROJECT ID: CDP 2020-0017: GR 2021-0016: DWG 531-1A ENGINEER OF WORK: PREPARED FOR: SCOTT SAREM 6684 LEMON LEAF DRIVE, CARLSBAD, CA 92011 TEL: (760)533-2470 PREPARED BY: TOAL ENGINEERING, INC. 139 AVENIDA NAVARRO SAN CLEMENTE, CA 92672 TEL: (949)492-8586 DATE: 7/23/2021 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 3: Structural BMP Maintenance Thresholds and Actions Attachment 4: Single Sheet BMP (SSBMP) Exhibit CERTIFICATION PAGE Project Name: SAREM RESIDENCE Project ID: CDP 2020-0017: GR 2021-0016: DWG 531 -1A 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. RCE 57587 Caleb Rios , PE Print Name Toal Engineering , Inc. Company July 23 , 2021 Date PROJECT VICINITY MAP source : http://ocpw.maps.arcgis.com/apps/PublicGallery \ '.l. S1 ~ ---✓ 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: SAREM RESIDENCE PROJECT ID: CDP 2020-0017 ; GR 2021-0016 ADDRESS: 4005 SKYLINE ROAD APN: 207-072-17 The project is (check one): New Development Redevelopment The total proposed disturbed area is: 26,435 ft2 ( 0.607 ) acres The total proposed newly created and/or replaced impervious area is: 14,100 ft2 ( 0.324 ) 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. X N/A C cityof Carlsbad □ □ - I I - 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 USEPAGreen 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. X X X X □ □ □ □ □ □ □ □ 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 surfacescollectively 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 ofimpervious surface collectively over the entire project site on an existing site of 10,000 square feet ormore of impervious surface? This includes commercial, industrial, residential, mixed-use, and publicdevelopment 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 moreof impervious surface collectively over the entire project site and supports a restaurant? A restaurant isa facility that sells prepared foods and drinks for consumption, including stationary lunch counters andrefreshment stands selling prepared foods and drinks for immediate consumption (Standard IndustrialClassification (SIC) code 5812).4.Is your project a new or redevelopment project that creates 5,000 square feet or more of impervioussurface collectively over the entire project site and supports a hillside development project? A hillsidedevelopment 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 moreof impervious surface collectively over the entire project site and supports a parking lot? A parking lot isa land area or facility for the temporary parking or storage of motor vehicles used personally forbusiness or for commerce. 6.Is your project a new or redevelopment project that creates and/or replaces 5,000 square feet or moreof impervious street, road, highway, freeway or driveway surface collectively over the entire projectsite? 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 moreof impervious surface collectively over the entire site, and discharges directly to an EnvironmentallySensitive 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 squarefeet 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 squarefeet 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 landand 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 ofimpervious surface or (2) increases impervious surface on the property by more than 10%? (CMC21.203.040)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. X X X X X X X X X X X □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ □ STEP4 TO BE COMPLETED FOR REDEVELOPMENT PROJECTS THAT ARE PRIORITY DEVELOPMENT PROJECTS (PDP) ONLY Complete the questions below regarding your redevelopment project (MS4 Permit Provision E.3.b.(2)): YES NO Does the redevelopment project result in the creation or replacement of impervious surface in an amount of less than 50% of the surface area of the previously existing development? Complete the percent impervious calculation below: Existing impervious area (A) = ____________ sq . ft. Total proposed newly created or replaced impervious area (8) = ____________ 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 "M pro·ect is a PDP ... "and complete applicant information. STEPS CHECK THE APPROPRIATE BOX AND COMPLETE APPLICANT INFORMATION !Kl My project is a PDP and must comply with PDP stormwater requirements of the BMP Manual. I understand I must prepare a Storm Water Quality Management Plan (SWQMP) for submittal at time of application. □ My project is a 'STANDARD PROJECT' OR EXEMPT from PDP and must only comply with 'STANDARD PROJECT' stormwater requirements of the BMP Manual. As part of these requirements, I will submit a "Standard Project Requirement Checklist Form E-36" and incorporate low impact development strategies throughout my project. Note: For projects that are close to meeting the PDP threshold, staff may require detailed impervious area calculations and exhibits to verify if 'STANDARD PROJECT' stormwater requirements apply. D My Project is NOT a 'development project' and is not subject to the requirements of the BMP Manual. Applicant Information and Signature Box ApplicantTitle: Ot.u~ Date: kAr;k/ * 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 0Nater 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. Th ' B ~ c· U 0 IS ox or ,tv se nly YES NO , City Concurrence: 12(' □ By: -P. (1.,<...t'v Date: ~-,3 -1--1 Project ID: c~ 0 l,,v?,o~ 0-c,7 E-34 Page 4 of 4 REV 04/17 SITE INFORMATION CHECKLIST Project Summary Information Project Name SAREM RESIDENCE Project ID CDP 2020-0017 ; GR2021-0016 ; DWG 531-1A Project Address 4005 SKYLINE ROAD CARLSBAD, CA 92008 Assessor's Parcel Number(s) (APN(s)) 207-072-17 Project Watershed (Hydrologic Unit) Carlsbad 904 Parcel Area 0.572 Acres (24,904 Square Feet) Existing Impervious Area (subset of Parcel Area) 0.139 Acres (6,043 Square Feet) Area to be disturbed by the project (Project Area) 0.607 Acres (26,435 Square Feet) Project Proposed Impervious Area (subset of Project Area) 0.324 Acres (14,100 Square Feet) Project Proposed Pervious Area (subset of Project Area) 0.274 Acres (12,335 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): (X) Existing development Previously graded but not built out Agricultural or other non-impervious use (X) Vacant, undeveloped/natural Description / Additional Information: The site includes an existing single-family residence with appurtenant hardscape, walls and landscape areas on the easterly half, and undeveloped natural slope on the westerly half. Existing Land Cover Includes (select all that apply): (X) Vegetative Cover (X) Non-Vegetated Pervious Areas (X) Impervious Areas Description / Additional Information: The existing land cover includes planter areas around the front and sides of the building, and natural area on the rear slope beyond the house. Existing parcel pervious area = 19,904 sq. ft. Underlying Soil belongs to Hydrologic Soil Group (select all that apply): NRCS Type A (X) NRCS Type B - See Soil Map from San Diego County Hydrology Manual (Attachment 1b) 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 (X) GW Depth > 20 feet Existing Natural Hydrologic Features (select all that apply): Watercourses Seeps Springs Wetlands (X) None Description of Existing Site Topography and Drainage: Under existing conditions, site runoff travels primarily via surface flow across the property in a westerly direction and onto the adjacent downstream property(s) to the west, and ultimately into Sunnyhill Drive (public street). It is assumed that runoff collected within drainage inlets around the existing building is discharged onto the natural rear slope on the westerly half of the property, although no outlets were uncovered during topographic survey of the site. A 2” - 4” high ridge in the Skyline Road right-of-way is intended to keep all street runoff within the right-of-way. Description of Proposed Site Development and Drainage Patterns Project Description / Proposed Land Use and/or Activities: The project consists of a new single-family residence with appurtenant hardscape, walls, pool, and landscape areas. The front yard features a driveway serving garages on either side of the front entry; the side yards include walkways and landscape areas; the rear yard is comprised of terraced patios, a swimming pool, a sport court, and landscaping improvements throughout. List/describe proposed impervious features of the project (e.g., buildings, roadways, parking lots, courtyards, athletic courts, other impervious features): Impervious surfaces include the proposed residence (4,200 sq. ft.), the driveway (3,400 sq. ft.), walkways/stairways/walls/pool (~5,700 sq. ft.), and a sport court (800 sq. ft.). List/describe proposed pervious features of the project (e.g., landscape areas): Pervious surfaces include planter areas adjacent to impervious walkways, permeable paving for the terraced rear patios, as well as a garden at the rear of the property. Does the project include grading and changes to site topography? (X) Yes No Description / Additional Information: Cut and fill of the existing rear slope is necessary to create the terraced rear patios. Does the project include changes to site drainage (e.g., installation of new storm water conveyance systems)? (X) Yes No Description / Additional Information: The proposed drainage system is designed to follow the existing drainage pattern and includes: 1) roof drains, drain inlets, and solid pipes to collect and convey all runoff to the rear of the site; 2) on-site treatment of project storm water via Biofiltration BMP located at the west end of the property; 3) underground storage to limit post-project discharge to match pre-project conditions; and 4) a drainage spreader at the west PL to distribute surface flow on to the adjacent property. Identify whether any of the following features, activities, and/or pollutant source areas will be present (select all that apply): (X) On-site storm drain inlets Interior floor drains and elevator shaft sump pumps Interior parking garages (X) Need for future indoor & structural pest control (X) Landscape/Outdoor Pesticide Use (X) 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 (X) Fire Sprinkler Test Water Miscellaneous Drain or Wash Water (X) 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): Property runoff will be collected and conveyed (via solid pipe) across the site in a westerly direction to an offline Biofiltration BMP (for on-site treatment). A flow control box will limit off-site discharge to the pre-project rate, utilizing an underground storage chamber to detain the difference between the pre- and post-project volumes during the storm peak (see separate Hydrology Study prepared by Toal Engineering, Inc.). Runoff is discharged via drainage spreader (a subsurface pipe with pop-up emitters equally spaced at the same surface elevation) designed to distribute the runoff across the rear property line and reduce downstream erosion potential. The project runoff ultimately makes its way to Sunnyhill Drive, where it is collected by the city storm drain system and discharged to Agua Hedionda Lagoon (Hydrologic Area 904.3 - Carlsbad Watershed Management Area). 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) and/or 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 YES NO Nutrients YES NO Heavy Metals N/A NO Organic Compounds N/A NO Trash & Debris YES NO Oxygen Demanding Substances YES NO Oil & Grease YES NO Bacteria & Viruses YES NO Pesticides YES NO 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. (X) 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): Runoff within Sunnyhill Drive flows in a southerly direction along the street before entering the City storm drain system via curb inlet catch basin at the intersection with Tamarack Avenue, and ultimately discharging to Agua Hedionda Lagoon. This project is located within the exemption boundary per the “Hydromodification Exemption Analyses for Select Carlsbad Watersheds,” prepared by Chang Consultants, dated September 17, 2015. 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. 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. N/A Optional Additional Information or Continuation of Previous Sections As Needed This space provided for additional information or continuation of information from previous sections as needed. N/A 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 theModel 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 beprovided. 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 isaddressed by the BMP (e.g., the project has no outdoor materials storage areas). Discussion/justification may beprovided. 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. Per Form I-8 (completed by Petra Geosciences and included herein) infiltration on this site with NRCS Type B soils is only partially feasible due to subsurface paralic terrace deposits. Per Form I-7 (included herein) the project site has insufficient landscape surface area and other conditions for harvest and reuse. Not feasible. The site has one Drainage Management Area (DMA), and the selected Structural BMP is PR-1: Biofiltration with partial retention. All site runoff will flow into a biofiltration system at the west end of the property for treatment before flowing off-site for discharge to Sunnyhill Drive. Storm events exceeding the design treatment volume will bypass the Biofiltration BMP. Structural BMP Summary Information [Copy this page as needed to provide information for each individual proposed structural BMP] Structural BMP ID No. 1 DWG 531-1A Sheet No. 8 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) (X) 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: (X) 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): All parcel runoff will be treated by a Biofiltration BMP with partial retention (PR-1). The system consists of surface ponding, soil media, and gravel storage. Design volume runoff entering the system will pond on the surface before filling the voids within the underlying media and gravel layers as it filters through via gravity. Filtered runoff is then discharged from the system via subsurface infiltration into the underlying soils or perforated underdrain pipe that connects back into the site drainage system for off-site discharge to Sunnyhill Drive. 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) Tabular Summary of DMAs Showing DMA ID matching DMA Exhibit, DMA Area, and DMA Type (Required)* (X) Included Attachment 1b County of San Diego Hydrology Manual Soil Hydrologic Group Map (X) Included 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. (X) Included 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. (X) Included 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 (X) Included Use this checklist to ensure the required information has been included on the DMA Exhibit: The DMA Exhibit must identify: (X) Underlying hydrologic soil group (X) Approximate depth to groundwater N/A Existing natural hydrologic features (watercourses, seeps, springs, wetlands) N/A Critical coarse sediment yield areas to be protected (if present) (X) Existing topography and impervious areas (X) Existing and proposed site drainage network and connections to drainage offsite (X) Proposed grading (X) Proposed impervious features (X) Proposed design features and surface treatments used to minimize imperviousness (X) Drainage management area (DMA) boundaries, DMA ID numbers, and DMA areas (square footage or acreage), and DMA type (i.e., drains to BMP, self-retaining, or self-mitigating) (X) Structural BMPs (identify location and type of BMP) E E E E E E EMAIN LEVELT/SLAB=298.32PAD=297.652-CARGARAGE1-CARGARAGEGYMT/SLAB=299.82PAD=299.15POOLBY OTHERSLOT 25 (POR)N89°28'48"E 286.90'N84°57'43"W 272.03'N08°14'58"W 79.37'4005 SKYLINE ROADMAP 2647 / CARLSBAD HEIGHTSLOT 24 (PORTION)207-072-17-00SAREM FAMILY TRUST 07-17-083975 SKYLINE ROADLOT 25 (PORTION)207-064-05-00COVIELLO FAMILY TRUST 06-04-974020 SUNNYHILL DRIVELOT 29207-064-04-00EDWARDS JOSHUA B & TERRIL REVOCABLE LIVING TR4030 SUNNYHILL DRIVELOT 30207-072-01-00TUOMI NATALIE FAMILYTRUST 04-24-95 4015 SKYLINE ROADLOT 24 (PORTION)207-072-16-00COX FAMILY 2001 TRUST 12-19-01R=1170.00 L=99.97'DMA-1DETAILBIOFILTRATION W/ PARTIAL RETENTION1A1.01DMA-1 TABLEWQMP LEGENDPROPOSED IMPERVIOUS PAVEMENTPROPOSED BUILDING ADDITIONPROPOSED STORM DRAININLETPROJECT AREA BOUNDARYPROPOSED BIOFILTRATION BMP1. THESE BMPS ARE MANDATORY TO BE INSTALLED PER MANUFACTURER'SRECOMMENDATIONS OR THESE PLANS.2. NO CHANGES TO THE PROPOSED BMPS ON THIS SHEET WITHOUT PRIORAPPROVAL FROM THE CITY ENGINEER.3. NO SUBSTITUTIONS TO THE MATERIAL OR TYPES OR PLANTING TYPESWITHOUT PRIOR APPROVAL FROM THE CITY ENGINEER.4. NO OCCUPANCY WILL BE GRANTED UNTIL THE CITY INSPECTION STAFFHAS INSPECTED THIS PROJECT FOR APPROPRIATE BMP CONSTRUCTIONAND INSTALLATION.BMP NOTES:PARTY RESPONSIBLE FOR MAINTENANCE:NAMEADDRESSPHONE NO.PLAN PREPARED BY:NAMEADDRESSPHONE NO.COMPANY5. REFER TO MAINTENANCE AGREEMENT DOCUMENT.6. SEE PROJECT SWMP FOR ADDITIONAL INFORMATION.BMP CONSTRUCTION AND INSPECTION NOTES:THE EOW WILL VERIFY THAT PERMANENT BMPS ARE CONSTRUCTEDAND OPERATING IN COMPLIANCE WITH THE APPLICABLEREQUIREMENTS. PRIOR TO OCCUPANCY THE EOW MUST PROVIDE:1. PHOTOGRAPHS OF THE INSTALLATION OF PERMANENT BMPSPRIOR TO CONSTRUCTION, DURING CONSTRUCTION, AND ATFINAL INSTALLATION.2. A WET STAMPED LETTER VERIFYING THAT PERMANENT BMPSARE CONSTRUCTED AND OPERATING PER THE REQUIREMENTSOF THE APPROVED PLANS.3. PHOTOGRAPHS TO VERIFY THAT PERMANENT WATER QUALITYTREATMENT SIGNAGE HAS BEEN INSTALLED.PRIOR TO RELEASE OF SECURITIES, THE DEVELOPER IS RESPONSIBLEFOR ENSURING THE PERMANENT BMPS HAVE NOT BEEN REMOVED ORMODIFIED BY THE NEW HOMEOWNER OR HOA WITHOUT THEAPPROVAL OF THE CITY ENGINEER.SCOTT SAREM4005 SKYLINE ROADCARLSBAD, CA 92008(760) 533-2470CALEB RIOS, P.E.TOAL ENGINEERING, INC.139 AVENIDA NAVARROSAN CLEMENTE, CA 92672(949) 492-8586BMP TYPEBMP ID #SYMBOL BMP NO.MAINTENANCEFREQUENCYBMP TABLEINSPECTION FREQUENCYQUANTITYTREATMENT CONTROLLOW IMPACT DESIGN (L.I.D.)SOURCE CONTROL4TRASH ENCLOSURESC-51PERVIOUSPAVEMENTSEMI-ANNUALLYSD-6B 2,540 SF.**ANNUALLYPROPOSED PERVIOUS PAVING2BIOFILTRATION W/PARTIAL RETENTIONMONTHLYPR-1423 SF.ANNUALLY11124ATTACHMENT 1aDMA EXHIBIT13 9 A v e n i d a N a v a r r oS a n C l e m e n t e , C A 9 2 6 7 29 4 9 . 4 9 2 . 8 5 8 6w w w . t o a l e n g i n e e r i n g . c o mC I V I L E N G I N E E R I N GL A N D S U R V E Y I N GS T O R M W A T E R Q U A L I T Y3STORM WATERDETENTION VAULTMONTHLYMP-50363 C.F.ANNUALLYDETAILWATER QUALITY SIGN··WATER QUALITY SIGN - SEE DETAIL HEREON3I FINISHED GRADE .......-::: --~'/»','>--«~ '/.('«"0'-1/ /0 ""~✓' ~ SITE RETAINING WALL PER ~ DIEGO COUNTY STANDARD ~ DRAWING C-05 (TYP.) ·>v':; ~ /; ,, -~ ~ ~' FLOW CONTROL DNERTER BOX AREA = 423 SQ. FT.; LAYOUT PER PLAN FINISHED GRADE 14" MIN. 8i PONDING 6"~ OVERFLOW DRAIN L1 LL~b~~-=----~t~~';:--'~~ I ;«' 18" f.llN. SOIL MEDIA THICKNESS (60% TO I 4'x4'x3" P.C.C. ,r 80% SAND, UP TO 20% TOPSOIL, AND UP I SPLASH BLOCK ~ TO 20% COMPOST; ALL % BY VOLUME). I );:::; INITIAL FILTRATION RATE = 8-12 IN./HR. I ~ (12" MAX.) PER APPENDIX E.13, SECTION I );:::;\ BF-2 OF BMP DESIGN MANUAL I 27" MIN. j" WASHED GRAVEL ,"<_,~,, '" . ' 1///)1//-U'/, '«<~~~ .----........__....._ __ ...., 6" DIA. PERF. PIPE (272.67 INV) @f----------NOT TO SCALE N:\200xx\20036\Reports\ WQMP\20036-SWQMP-exhibit.dwg 08/31/2021 16: 15 0 l~I 0 I I 0 r---------------;i 1, " :, ,: ~----------------L 0 0 --4• --~ □ 0 IIIIIII] 0 n TOAL ENGINEERING, INC. @)@@ CALEB RIOS R.C.E. 57587 DATE: ADJACENT HOUSE (TYP) I I" I 3 :w \ FG,HP I 310.42 J \ 307 .08 -;ti·Sl\ 1 ASPHALT \ 1:· ~ \ \\ 0 0 10 ---SCALE: 1"= 10'-0" 20 I I I I I I I I STA 7+~JJB BC (PER DWG!82-5 I . -~~-·& I PERMANENT WATER QUALITY TREATMENT FACILITY KEEPING OUR WATERWAYS CLEAN MAINTAIN WITH CARE -NO MODIFICATIONS WITHOUT AGENCY APPROVAL NOTES: POST SIGN IN BIOFILTRATION BASIN; SIGN SHALL BE VISIBLE AT ALL TIMES NOT TO SCALE SITIE AREA 0.572 IC, 24,904 S.F. DISTURBED AREA 0.607 IC, 26,435 S.F. HYDROLOGIC SOIL GROUP NRCS TYPE B DEPTH TO GROUNDWATIER >20 FT. POST-PROJECT PERVIOUS AREA 0.248 IC, 10,804 S.F. IMPERVIOUS AREA PRE-PROJECT 0.139 IC, 6,043 S.F. NEW OR REPLACEMENIT 0.324 IC, 14,100 S.F. POST-PROJECT 0.324 IC, 14,100 S.F. i5Hm'l CITY OF CARIBBAD I SHEETS I 1-----+----+---------------+-----+-----,1----+---1 L__j ENGINEERING DEPARTMENT l-----+----+---------------+-----+-----,1----+---I 1-----+----+---------------+-----+-----,1----+---1 DATE INITIAL DATE INITIAL DATE INITIAL ENGINEER OF WORK REVISION DESCRIPTION OTHER APPROVAL CITY APPROVAL GRADING PLANS FOR: SAREM RESIDENCE (4006 SKYLINE ROAD) GR2021-0018 PROJECT NO. I DRAWING NO.I CDP 2020-0017 . . !"^$ !"_$ Aù %&s( !"a$!"^$ !"^$ A© %&s( ?z Aª A¨ Aª Aª AÀ A¨ A¨ A© A© !"a$ !"_$ !"_$ !"_$ A© AÀ %&s(?j ?jA×AÀ ?h ?h AÀ AÀ AÛ !"_$ ?z !"_$?z !"a$ A¨ !"a$ !"^$ VISTA POWAY SANTEE LA MESA DEL MAR CORONADO EL CAJON CARLSBAD OCEANSIDE ENCINITAS SAN DIEGO ESCONDIDOSAN MARCOS CHULA VISTA LEMON GROVE SOLANA BEACH NATIONAL CITY IMPERIAL BEACH 116°15'0"W 116°15'0"W 116°30'0"W 116°30'0"W 116°45'0"W 116°45'0"W 117°0'0"W 117°0'0"W 117°15'0"W 117°15'0"W 117°30'0"W 117°30'0"W 33°30'0"N33°30'0"N33°15'0"N33°15'0"N33°0'0"N33°0'0"N32°45'0"N32°45'0"NCounty of San DiegoHydrology ManualSoil Hydrologic Group Legend Major Roads Incorporated City Bdy HYDROLOGIC SOIL GROUP Hydrologic Group Undefined Hydrologic Group A Hydrologic Group B Hydrologic Group C Hydrologic Group D No Soil Data THIS MAP IS PROVIDED WITHOUT WARRANTY OF ANY KIND,EITHER EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITEDTO, THE IMPLIED WARRANTIES OF MERCHANTABILITY ANDFITNESS FOR A PARTICULAR PURPOSE.Copyright SanGIS. All Rights Reserved. This product may contain information from the SANDAG Regional Information System which cannot be reproduced without the written permission of SANDAG. This product may contain information which has been reproduced with permission granted by Thomas Brothers Maps. Note: Soil Data Source USDA/NRCS SSURGO Soils 2007 ±3 0 31.5 Miles Riverside County Paci fic OceanImperial CountyM exico Orange County Project Site I I I I I I I I I I - - D DPW *GIS ~~,..~""~'"~"-':-"-• ..... .,.. ...................... ~.-._... Appendix I: Forms and Checklists I-2 February 2016 Harvest and Use Feasibility Checklist Form I-7 1. Is there a demand for harvested water (check all that apply) at the project site that is reliably present during the wet season? Toilet and urinal flushing Landscape irrigation Other:______________ 2. If there is a demand; estimate the anticipated average wet season demand over a period of 36 hours. Guidance for planning level demand calculations for toilet/urinal flushing and landscape irrigation is provided in Section B.3.2. [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? Yes / No 3b. Is the 36 hour demand greater than 0.25DCV but less than the full DCV? Yes / No 3c. Is the 36 hour demand less than 0.25DCV? Yes Harvest and use appears to be feasible. Conduct more detailed evaluation and sizing calculations to confirm that DCV can be used at an adequate rate to meet drawdown criteria. Harvest and use may be feasible. Conduct more detailed evaluation and sizing calculations to determine feasibility. Harvest and use may only be able to be used for a portion of the site, or (optionally) the storage may need to be upsized to meet long term capture targets while draining in longer than 36 hours. Harvest and use is considered to be infeasible. Is harvest and use feasible based on further evaluation? Yes, refer to Appendix E to select and size harvest and use BMPs. No, select alternate BMPs. X X X Toilet Flushing: 4 persons x 9.3 gallons/person/day x 36 hours x 1.5 day/36 hours = 56 gal (7.5 cu. ft.) Irrigation: 930** gallons/acre/36 hours x 0.334 acres = 311 gal (42 cu. ft.) 930 gallons represents 50% low water use and 50% high water use per Table B.3-3. 610 X X X □ □ □ Appendix I: Forms and Checklists I-3 February 2016 Categorization of Infiltration Feasibility Condition Form I-8 Part 1 - Full Infiltration Feasibility Screening Criteria Would infiltration of the full design volume be feasible from a physical perspective without any undesirable consequences that cannot be reasonably mitigated? Criteria Screening Question Yes No 1 Is the estimated reliable infiltration rate below proposed facility locations greater than 0.5 inches per hour? The response to this Screening Question shall be based on a comprehensive evaluation of the factors presented in Appendix C.2 and Appendix D. Provide basis: 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. No No The site will be graded such that compacted fill will cover the majority of the area as well as underlain by relatively impermeable paralic terrace deposits. The compacted fill and paralic terrace deposits possess little or no void space and therefore the infiltration rate is considered less than 0.5 inches per hour. Infiltration greater than 0.5 inches per hour would result in horizontal infiltration, causing seepage problems and would be detrimental to the project. Appendix I: Forms and Checklists I-4 February 2016 Form I-8 Page 2 of 4 Criteri a Screening Question Yes No 3 Can infiltration greater than 0.5 inches per hour be allowed without increasing risk of groundwater contamination (shallow water table, storm water pollutants or other factors) that cannot be mitigated to an acceptable level? The response to this Screening Question shall be based on a comprehensive evaluation of the factors presented in Appendix C.3. Provide basis: 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. Part 1 Result * If all answers to rows 1 - 4 are “Yes” a full infiltration design is potentially feasible. The feasibility screening category is Full Infiltration If any answer from row 1-4 is “No”, infiltration may be possible to some extent but would not generally be feasible or desirable to achieve a “full infiltration” design. Proceed to Part 2 *To be completed using gathered site information and best professional judgment considering the definition of MEP in the MS4 Permit. Additional testing and/or studies may be required by the City to substantiate findings. Yes Yes No Appendix I: Forms and Checklists I-5 February 2016 Form I-8 Page 3 of 4 Part 2 – Partial Infiltration vs. No Infiltration Feasibility Screening Criteria Would infiltration of water in any appreciable amount be physically feasible without any negative consequences that cannot be reasonably mitigated? Criteria Screening Question Yes No 5 Do soil and geologic conditions allow for infiltration in any appreciable rate or volume? The response to this Screening Question shall be based on a comprehensive evaluation of the factors presented in Appendix C.2 and Appendix D. Provide basis: 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. Yes Yes The site will be graded such that compacted fill will cover the majority of the area as well as be underlain by relatively impermeable paralic terrace deposits. The compacted fill and paralic terrace deposits possess little or no void space. Areas at the site could be designed for infiltration rates less than 0.5 inches per hour. The site will be graded such that compacted fill will cover the majority of the area as well as underlain by paralic terrace deposits. The compacted fill and paralic terrace deposits possess little or no void space. Areas at the site could be designed for infiltration without increasing risk of geotechnical hazards . Appendix I: Forms and Checklists I-6 February 2016 Form I-8 Page 4 of 4 Criteria Screening Question Yes No 7 Can Infiltration in any appreciable quantity be allowed without posing significant risk for groundwater related concerns (shallow water table, storm water pollutants or other factors)? The response to this Screening Question shall be based on a comprehensive evaluation of the factors presented in Appendix C.3. Provide basis: 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. Part 2 Result* If all answers from row 5-8 are yes then partial infiltration design is potentially feasible. The feasibility screening category is Partial Infiltration. If any answer from row 5-8 is no, then infiltration of any volume is considered to be infeasible within the drainage area. The feasibility screening category is No Infiltration. *To be completed using gathered site information and best professional judgment considering the definition of MEP in the MS4 Permit. Additional testing and/or studies may be required by the City to substantiate findings. Yes Yes Partial Infiltration 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 0.572 **C value = (0.9 x 0.324 ac (imp.)) + (0.14 x 0.19 ac (soil type B)) + (0.10 x 0.058 (pervious paving) 0.572 ac 0.566 N/A N/A 706 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 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 706 0.05* 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) * Design Infiltration Rate per Field Testing; see Petra Geosciences, Inc. report on the following pages. 1.8 4.5 423 8 18 126 580 12 16.4 46.4 870 225 435 318 24,904 0.566 423 423 Factor of Safety and Design Infiltration Rate Worksheet Form I-9 Factor Category Factor Description Assigned Weight (w) Factor Value (v) Product (p) p = w x v A Suitability Assessment Soil assessment methods 0.25 Predominant soil texture 0.25 Site soil variability 0.25 Depth to groundwater / impervious layer 0.25 Suitability Assessment Safety Factor, SA = p B Design Level of pretreatment/ expected sediment loads 0.5 Redundancy/resiliency 0.25 Compaction during construction 0.25 Design Safety Factor, SB = p Combined Safety Factor, Stotal= SA x SB Observed Infiltration Rate, inch/hr, Kobserved (corrected for test-specific bias) Design Infiltration Rate, in/hr, Kdesign = Kobserved / Stotal Supporting Data Briefly describe infiltration test and provide reference to test forms: ENGINEERS + GEOLOGISTS + ENVIRONMENTAL SCIENTISTS July 9, 2021 J.N. 20-155 MR. SCOTT SAREM 5796 Armada Drive, Suite 375 Carlsbad, California 92008 Subject: Evaluation of Infiltration Characteristics, Proposed Bio-Infiltration Basin, Proposed Single-Family Residence, 4005 Skyline Road, City of Carlsbad, San Diego County, California References: Attached Dear Mr. Sarem: At the request of Mr. Mark Browe with Toal Engineering, Petra Geosciences, Inc. (Petra) has performed percolation testing within the proposed bio-infiltration basin in the northwest corner of the property located at 4005 Skyline Drive in the city of Carlsbad, California. The purpose of our percolation testing was to evaluate the infiltration rate of the paralic deposits within the proposed bio-infiltration basin to determine a design infiltration rate in accordance with the City of Carlsbad BMP Design Manual. This letter presents the results of the falling-head percolation testing and design infiltration rate determination. The borehole percolation testing method was used in accordance with section D.3.3.2 of the City of Carlsbad BMP Design Manual. The borings for the percolation tests were advanced using a 6-inch diameter hand auger to depths of approximately 6-feet below the existing ground surface. As anticipated, Paralic deposits were encountered in both test borings. The excavated materials consisted of slightly clayey, fine- to medium-grained sands with scattered gravels and cobbles that were dense to very dense and moist. Percolation testing was performed in the bottom approximately 3-feet of the borehole. The locations of the percolation test borings are shown on the Updated Geotechnical Map, attached as Figure 1. The falling-head percolation test data were utilized in determining the test infiltration rate, It, expressed in units of inches/hour, utilizing the Porchet Method (RCFCWCD, 2011). Following a 24-hour presoak, field testing was conducted in a perforated-cased borehole (with ¾-inch gravel surrounding the pipe) at 30- minute intervals for a period of approximately 6-hours. Test data are attached in Appendix A. The infiltration rate, It, was calculated by determining the volumetric water flow through the wetted borehole surface area, expressed in terms of inches per hour. The Un-factored test results are summarized in the following table. Offices Strategically Positioned Throughout Southern California RIVERSIDE COUNTY OFFICE 40880 County Center Drive, Suite M, Temecula, CA 92591 T: 951.600.9271 F: 951.719.1499 For more information visit us online at www.petra-inc.com PETRA SOL/0 AS A ROCK GEOSCIENCES••c MR. SCOTT SAREM July 9, 2021 4005 Skyline Drive / Carlsbad J.N. 20-155 Page 2 Infiltration Test Results Test No. Area Test Location Approximate Test Zone (feet below existing grade) Geologic Unit / Soil Description Infiltration Test Rate, It (in/hr) P-1 Bio-infiltration Basin 3.1 – 6.0 Qvol (SC) 0.23 P-2 Bio-infiltration Basin 3.1 – 6.1 Qvol (SC) 0.01 The test data indicates the paralic deposits between 3.1 to 6.1-feet below existing site grades are moderately permeable to relatively impermeable. Variability is possible at other locations/depths within the site due to changes in both the material density and gradation. For the purposes of determining a design infiltration rate the observed infiltration rates were averaged, yielding an unfactored rate of 0.12 inches/hour. A factor of safety of 2.25 was determined using tables D5.1 and D5.2 of the City of Carlsbad BMP Design Manual and applied to the observed infiltration rate. Completion of the I-9 worksheet, attached as Figure 2, indicates a design infiltration rate of 0.05 in/hr should be used. This opportunity to be of service is sincerely appreciated. If you have any questions, please contact this office. Respectfully submitted, PETRA GEOSCIENCES, INC. 7/9/21 Bryan M. Rall Grayson R. Walker Project Geologist Principal Engineer CEG 2729 GE 871 BMR/GRW/lv Attachments: Figure 1 – Percolation Test Location Map Figure 2 – Form I-8 Figure 3 – Form I-9 Appendix A – Percolation Test Results Distribution: (1) Addressee (1) Scott Sarem via Email (1) Mark Browe via Email W:\2020-2025\2020\100\20-155 Scott Sarem (4005 Skyline Road, Carlsbad)\Reports\20-155 120 Infiltration Evaluation.docx ~PETRA ~ GEOSCIENCES""' SOLID AS A ROCK MR. SCOTT SAREM July 9, 2021 4005 Skyline Drive / Carlsbad J.N. 20-155 Page 3 REFERENCES City of Carlsbad, 2016, BMP Design Manual, for Permanent Site Design, Stormwater Treatment and Hydromodification Management, effective February 16. County of San Diego, 2020, County of San Diego BMP Design Manual, for Permanent Site Design, Storm Water Treatment and Hydromodification Management, Stormwater Requirements for Development Applications, Second Update to February 2016 Manual,” dated September 15. Petra Geosciences, Inc., 2020a, Preliminary Geotechnical Evaluation, Proposed Two-Story Residence, 4005 Skyline Road, APN 207-072-17-00, City of Carlsbad, San Diego County, California, dated May 11. , 2020b, Geotechnical Commentary on Soil Infiltration Characteristics, Proposed Two-Story Residence, 4005 Skyline Road, City of Carlsbad, San Diego County, California” dated May 28. , 2021, Response to Third Party Geotechnical Review (First), 4005 Skyline Road, Carlsbad, California, Project ID: CDP2020-0017, dated June 30. Toal Engineering, Inc., Grading Plans for Sarem Residence (4005 Skyline Road) GR2021-0016, Precise Grading Plan, Sheet 2 of 8, undated. ~PETRA ~ GEOSCIENCES""' SOLID AS A ROCK APPENDIX A PERCOLATION TEST RESULTS ~PETRA ~ GEOSCIENCES""' SOLIO AS A ROCK Total Depth of Boring, Dt (ft):6Diameter of Hole, D (in):6Diameter of Pipe, d (in):3Agg. Correction (% Voids):40Pre-soak depth (ft):3 1st Reading 2nd Reading303.16 3.40 2.88 10.42 2.08303.20 3.40 2.40 12.50 1.75303.05 3.32 3.24 9.26 2.27303.06 3.32 3.12 9.62 2.19303.11 3.34 2.76 10.87 1.96303.15 3.35 2.40 12.50 1.72303.07 3.33 3.12 9.62 2.19303.11 3.34 2.76 10.87 1.96303.09 3.33 2.88 10.42 2.03303.12 3.33 2.52 11.90 1.79303.07 3.30 2.76 10.87 1.93303.06 3.30 2.88 10.42 2.03 Percolation Rate:10.87 Minutes/Inch 1.93 gal/day/ft2 Infiltration Rate:0.23 Inches/Hour*(Porchet Method) r = D / 2 Ho = Dt - Do Hf = Dt - Df DH = ΔD = Ho - Hf Havg = (Ho + Hf) / 2 *Raw Number, Does Not Include a Factor of Safety Soil Description: (Boring Log) 0-2.5 Red brown dry silty sand, dry, loose 2.5-3.5 Orange brown clayey sand, moist, dense 3.5-6.0 Orange brown poorly graded sand, moist, very dense, contains gravels and cobbles Testing By: Bryan Rall June 30, 2021 DATE: July, 2021 J.N.: 20-155 Figure A-1 4005 Skyline Drive Carlsbad, California PERCOLATION TEST SUMMARY PETRA GEOSCIENCES, INC. COSTA MESA TEMECULA VALENCIA PALM DESERT CORONA SAN DIEGO Test Number: P-1 40880 County Center Drive, Suite MTemecula, CA 92591PHONE: (951) 600-9271 Perc. Rate (gal/day/ft^2) Shallow Percolation Test Method Time Interval (min) Depth to Water Surface Dw (ft) Change in Head (in) Perc. Rate (min/in) where Infiltration Rate, It =DH (60r) / Dt (r + 2Havg) -t~1- '" .~ Ow Ir-'-- -_l Dt ,i,· ~PETRA 1 ~ GEOSCIENCEs-1 Total Depth of Boring, Dt (ft):6.1Diameter of Hole, D (in):6Diameter of Pipe, d (in):3Agg. Correction (% Voids):40Pre-soak depth (ft):3 1st Reading 2nd Reading303.15 3.20 0.60 50.00 0.40303.15 3.17 0.24 125.00 0.16303.13 3.15 0.24 125.00 0.16303.15 3.16 0.12 250.00 0.08303.16 3.20 0.48 62.50 0.32303.13 3.15 0.24 125.00 0.16303.15 3.17 0.24 125.00 0.16303.12 3.15 0.36 83.33 0.24303.11 3.15 0.48 62.50 0.32303.15 3.17 0.24 125.00 0.16303.15 3.17 0.24 125.00 0.16303.17 3.19 0.24 125.00 0.07 Percolation Rate:125.00 Minutes/Inch 0.16 gal/day/ft2 Infiltration Rate:0.02 Inches/Hour*(Porchet Method) r = D / 2 Ho = Dt - Do Hf = Dt - Df DH = ΔD = Ho - Hf Havg = (Ho + Hf) / 2 *Raw Number, Does Not Include a Factor of Safety Soil Description: (Boring Log)0-2.5 Red brown silty sand, dry, loose 2.5-3.8 Orange brown clayey sand, moist, dense 3.8-6.0 Orange brown well graded sand, moist, very dense contains scattered gravel and cobbles Testing by Bryan Rall dated 6/30/21 DATE: July, 2021 J.N.: 20-155 Figure A-2 4005 Skyline Drive Carlsbad, California PERCOLATION TEST SUMMARY PETRA GEOSCIENCES, INC. COSTA MESA TEMECULA VALENCIA PALM DESERT CORONA SAN DIEGO P-2 40880 County Center Drive, Suite MTemecula, CA 92591PHONE: (951) 600-9271 Perc. Rate (gal/day/ft^2) Shallow Percolation Test Method Time Interval (min) Depth to Water Surface Dw (ft) Change in Head (in) Perc. Rate (min/in) where Infiltration Rate, It =DH (60r) / Dt (r + 2Havg) -t~1- '" .~ Ow Ir-'-- -_l Dt ,i,· ~PETRA 1 ~ GEOSCIENCEs-1 TP-4TP-2TP-1TP-3AA'B'BAfu(Qvop)Afu(Qvop)T.D.=6'T.D.=4'T.D.=5.2'T.D.=3.5'P-1P-2LEGENDApproximate location of Test PitT.D.=Total DepthGeologic Cross-SectionArtificial Fill-UndocumentedVery Old Paralic Deposits-Bracketed Where BuriedApproximte Location of Percolation BoringUPDATED GEOTECHNICAL MAP4005 Skyline RoadCarlsbad, CaliforniaFIGURE 1DATE: JULY 2021J.N: 20-155PETRA GEOSCIENCES, INC.500 La Terraza Blvd. Suite 150Escondido, California 92025PHONE: (951) 253-4458COSTA MESA TEMECULA VALENCIA PALM DESERT CORONA SAN DIEGOSCALE: 1"=20'TP-1T.D.=5.2'A A'Afu(Qvop)P-2\ \ \ \ N:\200xx\20036\Drow;ngs\c;vH\20036-gp-02.dwg 06/23/2021 09:30 J:>OOL BYOTHE:RS (PEil stf'~Tt PLAN J,NO PERMln CONSTRUCTION NOTES G)--CONSTRUCT CONCRETE DRIVEWAY /HARDSCAPE. SEE DETAIL ON SHEET 5. (D-CONSTRUCT TURF BLOCK DRIVEWAY. SEE LANDSCAPE PLANS. @-INSTALL 4" PVC SCH40 OR SOR35 PIPE DRAIN SYSTEM. @-INSTALL 6" PVC SCH40 OR SDR35 PIPE DRAIN SYSTEM. ®-INSTALL 8" PVC SCH40 OR SDR35 PIPE DRAIN SYSTEM. ©-INSTALL 6" DECK DRAIN NOS 918B W/ RISER & ADAPTOR, OR EQUAL. G)-INSTALL 6" ATRIUM DRAIN NOS 90 W/ RISER & ADAPTOR, OR EQUAL. ©-INSTALL 12" ATRIUM DRAIN, NOS 1280 W/ RISER & ADAPTOR OR EQUAL. ©-INSTALL 24" CONC. CATCH BASIN (BROOKS CB-2424 OR EQUAL). @-INSTALL BIOFILlRATION SYSTEM (423 S.F. MIN. AREA). SEE DETAIL ON SHEET 5. @-CONSTRUCT STORM WATER STORAGE VAULT. SEE DETAIL ON SHEET 4. @-CONSTRUCT DRAINAGE SPREADER. SEE DETAIL ON SHEET 5. @-INSTALL 5" CHANNEL DRAIN W/ LIGHT TRAFFlC GRATE (NOS 864GMTL OR EQUAL.) @-coNSTRUCT 12" WIDE CONCRETE V-DITCH. SEE DETAIL ON SHEET 5. @-INSTALL 1" WATER METER AND SERVICE W/ SPRINKLER PER CITY STD. DWG. NO. W-3A. @-INSTALL PERVIOUS PAVING ON WALKWAYS/PATIOS AS SHOWN (SEE LANDSCAPE PLAN). @-INSTALL SUBDRAIN PER SOILS REPORT. SEE DETAIL ON SHEET 5. @-DOWNSPOUT (PER ROOFING CONTRACTOR). SEE DETAIL ON SHEET 5. NOTICE TO CONTRACTOR REQUIRED CERTIFICATIONS/ APPROVALS In addition to any certifications required by the agencies having jurisdiction over this project, the following approvals from the Civil engineer of record are required: 1. Foundation forms for improvements on or abutting property lines is required prior to concrete pour. 2. Location, size, and depth of all drain lines prior to backfill. CIVIL ENGINEERING LANO SURVEYING STORMWATER QUALITY 1S9 Av~1lda Navarro San •:lemente, CA 9i672 e 4 9 4 9 2 . a s s 6 -,;ww. toe Ieng lneerl n g .com :,6 4015 SKYLINE RQAD WT 24(PDR.) 5' MIN. J 6' MAX. J. P.L VIN'll FENCE / (SLOPE /WITH GRADE, SEE LANDSCAPE PitN) I ADDITIONAL NOTES A\~--HO.'JS 1. ALL ROOFS SHAU. BE GUTTERED & DOWNSPOUTS CONNECTED TO STORM DRAIN SYSTEM. 2. PAD ELEVATIONS ARE BASED ON 4" CONCRETE SLAB OVER 10-MIL VAPOR BARRIER OVER 4" of CLEAN AGGREGATIE BASE PER FOUNDATION PLAN (NEAL SHAH STRUCTURAL ENGINEERING DATED 2/26/2021). CONTRACTOR SHALL VERIFY ALL PAD ELEVATIONS W/ SOILS ENGINEER AND STRUCTURAL ENGINEER PRIOR TO GRADING. 11 EASEMENT NOTES I I r I I r I I r 1ST. CE GR EC OO-=t-11-1 ~,· i 30' r 3. WHERE EXTERIOR/INTERIOR UTILITY TRENCHES ARE PROPOSED IN A DIRECTION TIHAT PARALL.Il.S Nfr BUILDING FOOTING, THE BOTTOM OF THE TRENCHES SHALL NOT EXTEND BELOW A 1:1 PLANE PROJECTIED DOWNWARD FROM THE BOTTOM EDGE OF FOOTING. WHERE THIS OCCURS, ADJACENT FOOTING SHAU. BE DEEPENED OR UTILITY CONSTRUCTED AND BACKFILLED PRIOR TO BUILDING CONSTRUCTION. ALL EASEMENTS LISTED HEREON ARE PER A PRELIMINARY TITLE REPORT PREPARED BY FIRST AMERICAN mu: COMPANY, FILE NO.DIV-6066955 DATED OCTOBER 4, 2019 UNLESS NOTIED OTHERWISE. 0 4. FOR BUILDING FOOTING AND FOUNDATION DESIGN SEE STRUCTURAL PLANS. 5. ALL RECOMMENDATIONS ~THIN THE SOILS REPORT FOR THIS PROJECT PREPARED BY PETRA GEOSCIENCES. IN REPORT NO. 20-155 DATIED MAY 11, 2020, AND ALL ADDENDA THERETO, ARE CONSIDERED A PART OF THIS 6. ALL DRAIN LINES SHALL HAVE A MINIMUM SLOPE OF 1X TOWARDS OUTLETS. WALL NOTES 1. WALLS SHOWN HEREON FOR INFORMATION ONLY ANO ARE TO BE CONSTRUCTIEO PER SEPARATE PIAN/PERMIT. 2. ALL PROPOSED WALLS ARE ANTICIPATED TO BE CMU UNLESS OTHERWISE NOTED: SEE SITE WALL PLANS FOR DESIGN INFORMATIION. 3. NO WALLS OR FENCES ARE TO EXCEED 6' IN HEIGHT MEASURED FROM LOWEST ADJACENT GRADE AND NOT T ~ PETRA >------------< EXCEED 42" WITHIN THE REQUIRED FRONT YARD SETBACK. HEIGHT SHAU. INCLUDE ANY REQUIRED SAFETY ~ GEOSCIENCES'"' D SEWER, BER 13, COUNTY. M RECORD 0 10 20 I'!--I I stXE. I Id C II AS BUILT" RCE ___ EXP, ___ _ DATE REVIEl,/ED BY• r1-::::]::::[::::::~~::::::::::::::~:::::~::::~:::~~===~~==~~~~~1~N~sP~E~c~r~□R~~~;.;;;;:::;;;;;:::;:::~D~A~TE=:d I SH2EET I CITY OF CARlSBAD I SHEE8TS I CALEB RIOS R.C.E. 57587 DATE: 1----+--l----------------+--+---+------ir------t ENGINEERING DEPARTMENT 1----+--l----------------+--+---+------i;-------t DATE INmAL DATE INITIAL DATE INITIAL ENGINEER OF WORK RE\IISION DESCRIPTION OTHER APPROVAL OTY APPROVAL GRADING Pl.ANS FOR: SAREM RESIDENCE ( 4005 SICYLINE ROAD) GR2021-0016 PRECISE GRADING PLAN APPROVED: JASON S. GELDERT PROJECT NO, DRAWING NO. CDP 2020-001 7 531-lA GRADING SUBMITTAL NO. 1 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 (X) SD-D Permeable Pavement (Site Design BMP) www.sandiegocounty.gov/stormwater E-37 Effective September 15, 2020 Summary of Standard Inspection and Maintenance The property owner is responsible to ensure inspection, operation and maintenance of permanent BMPs on their property unless responsibility has been formally transferred to an agency, community facilities district, homeowners association, property owners association, or other special district. Maintenance frequencies listed in this table are average/typical frequencies. Actual maintenance needs are site-specific, and maintenance may be required more frequently. Maintenance must be performed whenever needed, based on maintenance indicators presented in this table. The BMP owner is responsible for conducting regular inspections to see when maintenance is needed based on the maintenance indicators. During the first year of operation of a structural BMP, inspection is recommended at least once prior to August 31 and then monthly from September through May. Inspection during a storm event is also recommended. After the initial period of frequent inspections, the minimum inspection and maintenance frequency can be determined based on the results of the first year inspections. Threshold/Indicator Maintenance Action Inspection and Maintenance Frequency Preventive vacuum/regenerative air street sweeping Pavement should be swept with a vacuum power or regenerative air street sweeper to maintain infiltration through paving surface • Schedule/perform this preventive action at least twice per year. Accumulation of sediment, litter, or debris on permeable pavement surface Remove and properly dispose of accumulated materials. Inspect tributary area for exposed soil or other sources of sediment and apply stabilization measures to sediment source areas. Apply source control measures as applicable to sources of litter or debris. • Inspect monthly and after every 0.5-inch or larger storm event. • Remove any accumulated materials found at each inspection. SD-D Permeable Pavement (Site Design BMP) www.sandiegocounty.gov/stormwater E-38 Effective September 15, 2020 Threshold/Indicator Maintenance Action Inspection and Maintenance Frequency Weeds growing on/through the permeable pavement surface Remove weeds and add features as necessary to prevent weed intrusion. Use non-chemical methods (e.g., instead of pesticides, control weeds using mechanical removal, physical barriers, and/or physical changes in the surrounding area adjacent to pavement that will preclude weed intrusion into the pavement). • Inspect monthly. • Remove any weeds found at each inspection. Standing water in permeable paving area following a storm event, or runoff is observed overflowing off the permeable paving surface during a storm event This condition requires investigation of why infiltration is not occurring. If feasible, corrective action shall be taken to restore infiltration (e.g., pavement should be swept with a vacuum power or regenerative air street sweeper to restore infiltration rates, clear underdrains if underdrains are present). BMP may require retrofit if infiltration cannot be restored. The County reviewer shall be contacted prior to any repairs or reconstruction. • Inspect monthly and after every 0.5-inch or larger storm event. If standing water is observed, increase inspection frequency to after every 0.1-inch or larger storm event. • Maintain when needed. SD-D Permeable Pavement (Site Design BMP) www.sandiegocounty.gov/stormwater E-39 Effective September 15, 2020 Threshold/Indicator Maintenance Action Inspection and Maintenance Frequency Presence of mosquitos/larvae For images of egg rafts, larva, pupa, and adult mosquitos, see http://www.mosquito.org/biology If mosquitos/larvae are observed: first, immediately remove any standing water by dispersing to nearby landscaping; second, make corrective measures as applicable to restore BMP drainage to prevent standing water. If mosquitos persist following corrective measures to remove standing water, or if the BMP design does not meet the 96-hour drawdown criteria because the underlying soils do not have the infiltration capacity expected, the County reviewer shall be contacted to determine a solution. A different BMP type, or a Vector Management Plan prepared with concurrence from the County of San Diego Department of Environmental Health, may be required. • Inspect monthly and after every 0.5-inch or larger storm event. If mosquitos are observed, increase inspection frequency to after every 0.1-inch or larger storm event. • Maintain when needed. Damage to permeable paving surface (e.g., cracks, settlement, misaligned paver blocks, void spaces between paver blocks need fill materials replenished) Repair or replace damaged surface as appropriate. • Inspect annually. • Maintain when needed. PR-1 Biofiltration with Partial Retention www.sandiegocounty.gov/stormwater E-111 Effective September 15, 2020 Summary of Standard Inspection and Maintenance The property owner is responsible to ensure inspection, operation and maintenance of permanent BMPs on their property unless responsibility has been formally transferred to an agency, community facilities district, homeowners association, property owners association, or other special district. Maintenance frequencies listed in this table are average/typical frequencies. Actual maintenance needs are site-specific, and maintenance may be required more frequently. Maintenance must be performed whenever needed, based on maintenance indicators presented in this table. The BMP owner is responsible for conducting regular inspections to see when maintenance is needed based on the maintenance indicators. During the first year of operation of a structural BMP, inspection is recommended at least once prior to August 31 and then monthly from September through May. Inspection during a storm event is also recommended. After the initial period of frequent inspections, the minimum inspection and maintenance frequency can be determined based on the results of the first year inspections. Threshold/Indicator Maintenance Action Inspection and Maintenance Frequency Accumulation of sediment, litter, or debris Remove and properly dispose of accumulated materials, without damage to the vegetation or compaction of the media layer. • Inspect monthly. If the BMP is 25% full* or more in one month, increase inspection frequency to monthly plus after every 0.1- inch or larger storm event. • Remove any accumulated materials found at each inspection. Obstructed inlet or outlet structure Clear blockage. • Inspect monthly and after every 0.5-inch or larger storm event. • Remove any accumulated materials found at each inspection. Damage to structural components such as weirs, inlet or outlet structures Repair or replace as applicable. • Inspect annually. • Maintain when needed. Poor vegetation establishment Re-seed, re-plant, or re-establish vegetation per original plans. • Inspect monthly. • Maintain when needed. PR-1 Biofiltration with Partial Retention www.sandiegocounty.gov/stormwater E-112 Effective September 15, 2020 Threshold/Indicator Maintenance Action Inspection and Maintenance Frequency Dead or diseased vegetation Remove dead or diseased vegetation, re-seed, re-plant, or re-establish vegetation per original plans. • Inspect monthly. • Maintain when needed. Overgrown vegetation Mow or trim as appropriate. • Inspect monthly. • Maintain when needed. 2/3 of mulch has decomposed, or mulch has been removed Remove decomposed fraction and top off with fresh mulch to a total depth of 3 inches. • Inspect monthly. • Replenish mulch annually, or more frequently when needed based on inspection. Erosion due to concentrated irrigation flow Repair/re-seed/re-plant eroded areas and adjust the irrigation system. • Inspect monthly. • Maintain when needed. Erosion due to concentrated storm water runoff flow Repair/re-seed/re-plant eroded areas, and make appropriate corrective measures such as adding erosion control blankets, adding stone at flow entry points, or minor re- grading to restore proper drainage according to the original plan. If the issue is not corrected by restoring the BMP to the original plan and grade, the County reviewer shall be contacted prior to any additional repairs or reconstruction. • Inspect after every 0.5-inch or larger storm event. If erosion due to storm water flow has been observed, increase inspection frequency to after every 0.1-inch or larger storm event. • Maintain when needed. If the issue is not corrected by restoring the BMP to the original plan and grade, the County reviewer shall be contacted prior to any additional repairs or reconstruction. Standing water in BMP for longer than 24 hours following a storm event Surface ponding longer than approximately 24 hours following a storm event may be detrimental to vegetation health 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. • Inspect monthly and after every 0.5-inch or larger storm event. If standing water is observed, increase inspection frequency to after every 0.1-inch or larger storm event. • Maintain when needed. PR-1 Biofiltration with Partial Retention www.sandiegocounty.gov/stormwater E-113 Effective September 15, 2020 Threshold/Indicator Maintenance Action Inspection and Maintenance Frequency Presence of mosquitos/larvae For images of egg rafts, larva, pupa, and adult mosquitos, see http://www.mosquito.org/biology If mosquitos/larvae are observed: first, immediately remove any standing water by dispersing to nearby landscaping; second, make corrective measures as applicable to restore BMP drainage to prevent standing water. If mosquitos persist following corrective measures to remove standing water, or if the BMP design does not meet the 96-hour drawdown criteria due to release rates controlled by an orifice installed on the underdrain, the County reviewer shall be contacted to determine a solution. A different BMP type, or a Vector Management Plan prepared with concurrence from the County of San Diego Department of Environmental Health, may be required. • Inspect monthly and after every 0.5-inch or larger storm event. If mosquitos are observed, increase inspection frequency to after every 0.1-inch or larger storm event. • Maintain when needed. Underdrain clogged Clear blockage. Inspect if standing water is observed for longer than 24-96 hours following a storm event. Maintain when needed. ATTACHMENT 4 City standard Single Sheet BMP (SSBMP) Exhibit [Use the City’s standard Single Sheet BMP Plan.] See DMA Exhibit in Attachment 1a E E E E E E EMAIN LEVELT/SLAB=298.32PAD=297.652-CARGARAGE1-CARGARAGEGYMT/SLAB=299.82PAD=299.15POOLBY OTHERSLOT 25 (POR)N89°28'48"E 286.90'N84°57'43"W 272.03'N08°14'58"W 79.37'4005 SKYLINE ROADMAP 2647 / CARLSBAD HEIGHTSLOT 24 (PORTION)207-072-17-00SAREM FAMILY TRUST 07-17-083975 SKYLINE ROADLOT 25 (PORTION)207-064-05-00COVIELLO FAMILY TRUST 06-04-974020 SUNNYHILL DRIVELOT 29207-064-04-00EDWARDS JOSHUA B & TERRIL REVOCABLE LIVING TR4030 SUNNYHILL DRIVELOT 30207-072-01-00TUOMI NATALIE FAMILYTRUST 04-24-95 4015 SKYLINE ROADLOT 24 (PORTION)207-072-16-00COX FAMILY 2001 TRUST 12-19-01R=1170.00 L=99.97'DMA-1DETAILBIOFILTRATION W/ PARTIAL RETENTION1PERVIOUSPAVEMENTSEMI-ANNUALLYSD-6B 2,540 SF.ANNUALLYPROPOSED PERVIOUS PAVING2BIOFILTRATION W/PARTIAL RETENTIONMONTHLYPR-1423 SF.ANNUALLYDMA-1 TABLEWQMP LEGENDPROPOSED IMPERVIOUS PAVEMENTPROPOSED BUILDING ADDITIONPROPOSED STORM DRAININLETPROJECT AREA BOUNDARYPROPOSED BIOFILTRATION BMP1. THESE BMPS ARE MANDATORY TO BE INSTALLED PER MANUFACTURER'SRECOMMENDATIONS OR THESE PLANS.2. NO CHANGES TO THE PROPOSED BMPS ON THIS SHEET WITHOUT PRIORAPPROVAL FROM THE CITY ENGINEER.3. NO SUBSTITUTIONS TO THE MATERIAL OR TYPES OR PLANTING TYPESWITHOUT PRIOR APPROVAL FROM THE CITY ENGINEER.4. NO OCCUPANCY WILL BE GRANTED UNTIL THE CITY INSPECTION STAFFHAS INSPECTED THIS PROJECT FOR APPROPRIATE BMP CONSTRUCTIONAND INSTALLATION.BMP NOTES:PARTY RESPONSIBLE FOR MAINTENANCE:NAMEADDRESSPHONE NO.PLAN PREPARED BY:NAMEADDRESSPHONE NO.COMPANY5. REFER TO MAINTENANCE AGREEMENT DOCUMENT.6. SEE PROJECT SWMP FOR ADDITIONAL INFORMATION.BMP CONSTRUCTION AND INSPECTION NOTES:THE EOW WILL VERIFY THAT PERMANENT BMPS ARE CONSTRUCTEDAND OPERATING IN COMPLIANCE WITH THE APPLICABLEREQUIREMENTS. PRIOR TO OCCUPANCY THE EOW MUST PROVIDE:1. PHOTOGRAPHS OF THE INSTALLATION OF PERMANENT BMPSPRIOR TO CONSTRUCTION, DURING CONSTRUCTION, AND ATFINAL INSTALLATION.2. A WET STAMPED LETTER VERIFYING THAT PERMANENT BMPSARE CONSTRUCTED AND OPERATING PER THE REQUIREMENTSOF THE APPROVED PLANS.3. PHOTOGRAPHS TO VERIFY THAT PERMANENT WATER QUALITYTREATMENT SIGNAGE HAS BEEN INSTALLED.PRIOR TO RELEASE OF SECURITIES, THE DEVELOPER IS RESPONSIBLEFOR ENSURING THE PERMANENT BMPS HAVE NOT BEEN REMOVED ORMODIFIED BY THE NEW HOMEOWNER OR HOA WITHOUT THEAPPROVAL OF THE CITY ENGINEER.SCOTT SAREM4005 SKYLINE ROADCARLSBAD, CA 92008(760) 533-2470CALEB RIOS, P.E.TOAL ENGINEERING, INC.139 AVENIDA NAVARROSAN CLEMENTE, CA 92672(949) 492-8586BMP TYPEBMP ID #SYMBOL BMP NO.MAINTENANCEFREQUENCYBMP TABLEINSPECTION FREQUENCYQUANTITYTREATMENT CONTROLLOW IMPACT DESIGN (L.I.D.)SOURCE CONTROL4TRASH ENCLOSURESC-5111248531-1A813 9 A v e n i d a N a v a r r oS a n C l e m e n t e , C A 9 2 6 7 29 4 9 . 4 9 2 . 8 5 8 6w w w . t o a l e n g i n e e r i n g . c o mC I V I L E N G I N E E R I N GL A N D S U R V E Y I N GS T O R M W A T E R Q U A L I T Y3STORM WATERDETENTION VAULTMONTHLYMP-50363 C.F.ANNUALLY3DETAILWATER QUALITY SIGN··WATER QUALITY SIGN - SEE DETAIL HEREONI FINISHED GRADE .....---:: ~ \.~-0 " '/.('«(~</ //~ "'*;,-' ~ SITE RETAINING WALL PER ~/ DIEGO COUNTY STANDARD ~, DRAWING C-05 (TYP.) A.1/, '» /,; ,;, ;,)' /,; ~ ~' , 283.67 TW 276.33 TF <61~~ I ki~~ I ~b~ <~ .. :~~~ ~~~ I •§/!,. I ?. I I \ AREA = 423 SQ. FT.; LAYOUT PER PIAN 14" MIN. 6"0 OVERFLOW DRAIN FINISHED GRADE , /7✓ . .. /I I/ »Y,~ ::<,<01/, ,~ANLET PIPE 1/,' FROM DIVERTER BOX I 0 18" MIN. SOIL MEDIA THICKNESS (60'1: TO I 4'x4'x3" P.C.C. "'' 80'1: SAND, UP TO 20'1: TOPSOIL, AND UP I SPLASH BLOCK {/ TO 20'1: COMPOST; ALL ,i: BY VOLUME). I ,Y( 1/, INITIAL FILTRATION RATE = 8-12 IN./HR. I ~ (12" MAX.) PER APPENDIX E.13, SECTION I ~\ BF-2 OF BMP DESIGN MANUAL. 11-------"i.------1 ----1'-'',6.'_-'l I ~) 3" CHOKER / ¾° -t PEA GRAVEL I Y) 12· //, :v. :( ~ -v ' '<\_ w" r?) 27" MIN. i" WASHED GRAVEL " ,\_'0,,"" . . '~~~~ .----....__..__ __ _,, 6" DIA. PERF. PIPE .----_.__....__ __ ~ (272.67 INV) @--------NOT TO SCALE N:\200xx\20036\Reports\ WQMP\20036-SWQMP-exhibit.dwg 08/31/2021 16: 17 0 128883 0 I>> • . I ... . . . 0 r---------------;i 1, " :, ,: ~----------------L 0 0 == 4"== ~ □ 0 IIIIIII] 0 n TOAL ENGINEERING, INC. @)@@ CALEB RIOS R.C.E. 57587 DATE: 0 310.42 \ 307 .08 lF J!'J'•• 1 ASPHALT \ ':"' .,,... \ . I I 0 10 20 SCALE: 1 "= 10'-o" I I I I I I I I I I ~ \ I ADJACENT HOUSE (TYP) 309.08 TW \ \07.08 TF \ \ I STA 7+~JJB BC (PER DWG!82-5 I . -~~-·& I PERMANENT WATER QUALITY TREATMENT FACILITY KEEPING OUR WATERWAYS CLEAN MAINTAIN WITH CARE -NO MODIFICATIONS WITHOUT AGENCY APPROVAL NOTES: POST SIGN IN BIOFILTRATION BASIN; SIGN SHALL BE VISIBLE AT ALL TIMES NOT TO SCALE SITE AREA 0.572 AC 24,904 S.F. DISTURBED AREA 0.607 AC 26,435 S.F. HYDROLOGIC SOIL GROUP NRCS TYPE B DEPTH TO GROUNDWATER >20 FT. POST-PROJECT PERVIOUS AREA 0.248 AC 10,804 S.F. IMPERVIOUS AREA PRE-PROJECT 0.139 AC 6,043 S.F. NEW OR REPLACEMENT 0.324 AC 14,100 S.F. POST-PROJECT 0.324 AC 14,100 S.F. l----+---1-----------~e-----l---l----l.--1 fsHml CITY OF CARIBBAD I SHEETS I L_j ENGINEERING DEPARTMENT GRADING PLANS FOR: SAREM RESIDENCE (4006 SKYLINE ROAD) 1----+----+---------------+----+----lf----l-------l GR2021-0018 SINGLE SHEET BMP SITE PLAN CD2021-0011 1-----+---+--------------+----+----lf---+----I APPROVED: JASON S. GELDERT ENGINEERING MANAGER RCE 63912 EXPIRES 9 /30 /22 DATE 1----c~-+----+---------------+----+----lf----l-------l DWN BY: u.•.M. DATE INITIAL >--DA_TE~_IN_lll_AL-+-_DA_TE~_IN_lll_AL-1 CHKD BY: __ ENGINEER OF WORK REVISION DESCRIPTION OTHER APPROVAL CITY APPROVAL RVWD BY: PROJECT NO. I DRAWING NO.I CDP 2020-0017 . . GRADING SUBMITTAL NO. 3