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HomeMy WebLinkAboutCT 11-02; LA COSTA VISTA; STORM WATER MANAGEMENT PLAN; 2013-05-13STORM WATER MANAGEMENT PLAN SWMP 13-04 FOR Project Site: LA COSTA VISTA Project No. CT 11-02, DWG 477-7A 7500 Jerez Court Carlsbad, California Prepared For: TMS JEREZ INVESTMENTS, LLC 19196 Sierra Isabelle Irvine, California 92603 Date Prepared: May 13, 2013 Prepared By: DMS CONSULTANTS. INC. CIVIL N G I N E r R S 12371 Lewis Street, Suite 203 Garden Grove, CA 92840 714.740.8840 La Costa Vista - Storm Water Management Plan City of Carlsbad STORM WATER MANAGEMENT PLAN SWMP 13-04 For LA COSTA VISTA PROJECT NO. CT 11-02 DWG 477-7A Prepared By: DMS CONSULTANTS, INC. SURENDER DEWAN, P.E. 12371 LEWIS STREET, SUITE 203 GARDEN GROVE, CA 92840 714.740.8840 8urender@DMSConsultantslnc.conn Prepared For: TMS JEREZ INVESTMENTS, LLC 19196 SIERRA ISABELLE IRVINE, CA 92603 MAY 13, 2013 May 13, 2013 f'^S^ ^ La Costa Vista - Storm Water Management Plan CERTIFICATION This Storm Water Management Plan (SWMP) has been prepared under the direction of the following Registered Civil Engineer. The Registered Civil Engineer (Engineer) attests to the technical information contained herein and the engineering data upon which the following design, recommendations, conclusions and decisions are based. The selection, sizing, and preliminary design of stormwater treatment and other control measures in this report meet the requirements of Regional Water Quality Control Board Order R9- 2007-0001 anri subsequent amendments. Surender Dewan, P.E. REGISTERED CIVIL ENGINEER Date OWNER'S CERTIFICATION This Storm Water Management Plan (SWMP) has been prepared for TMS Development, LLC by DMS Consultants, Inc. The SWMP is intended to comply with the requirements of the City of Carlsbad, Standard Urban Stormwater Management Plan (SUSMP) Management Program and Stormwater Ordinance, as well as the Municipal Stormwater Permit which requires the preparation of SWMPs for priority development projects. The undersigned, while it owns the subject property, is responsible for the implementation of the provisions of this SWMP. The undersigned will ensure that this plan is amended as appropriate to reflect up-to-date conditions on the site consistent with the current Standard Urban Stormwater Management Plan (SUSMP) and the intent of the NPDES/MS4 Permit for Waste Discharge Requirements as authorized by the State and EPA. Once the undersigned transfers its interest in the property, its successors-in-interest shall bear the aforementioned responsibility to implement and amend the SWMP. An appropriate number of approved and signed copies of this dQCuqient shall be available on the subject site in perpetuity. Signed: Name: Company/Owner: Address: Telephone #: TonySfPeddo (/ Title: Owner TMS Jerez Investments, LLC 19196 Sierra Isabelle Irvine, California 92603 951.801.0888 Date: May 13, 2013 Page 2 La Costa Vista - Storm Water Management Plan TABLE OF CONTENTS CERTIFICATION 1.0 INTRODUCTION 5 2.0 APPLICABILITY AND PROJECT TYPE 6 3.0 PROJECT OVERVIEW 7 3.1 Project Location 7 3.2 Project Description 7 3.3 Project Size 7 3.4 Impervious and Pervious Surface areas 7 4.0 PROJECT SITE ASSESSMENT 8 4.1 Land Use and Zoning 8 4.2 Existing Topography 8 4.3 Existing and Proposed Drainage 8 4.4 Watershed and Receiving Waters 8 4.5 303(d) Listed Receiving Waters 8 4.6 Total Maximum Daily Loads (TMDLs) 9 4.7 Soil Type(s) and Conditions 9 5.0 POLLUTANTS OF CONCERN 10 5.1 Project Categories and Features 10 5.2 Project Watershed Information 10 5.3 Hydromodification 11 6.0 BEST IVIANAGEMENT PRACTICES (BMPs) 12 6.1 LID Site Design Strategies and BMPs 12 6.1.1 Optimize the Site Layout 12 6.1.2 Flow Through Planters and Bioretention with Vault 12 6.1.3 Disperse Runoff 12 6.1.4 Integrated Management Practices (IMPs) 12 6.2 Source Control BMPs 13 6.3 Treatment Control BMPs 15 6.3.1 Selection 15 6.3.2 Design and Sizing 15 May 13, 2013 Page 3 La Costa Vista - Storm Water Management Plan 7.0 PROJECT PLAN(s) & BMP LOCATION MAP 16 8.0 BMP MAINTENANCE 17 8.1 Facility Ownership & Maintenance Agreements 17 8.2 Operations, Maintenance and Inspection 17 8.2.1 Typical Maintenance Requirements 17 8.2.2 Operation and Maintenance (O&M) Plan 17 8.2.3 Project BMP Verification 17 8.2.4 Annual BMP Operation and Maintenance Verification 17 APPENDIX Appendix A BMP Plan Appendix B Grading Plan Appendix C Soils Report Appendix D Hydrology Study (Pre and Post Construction Conditions) Appendix E Permeable Pavers Appendix F Calculations May 13,2013 Page 4 La Costa Vista - Storm Water Management Plan 1.0 INTRODUCTION This Storm Water Management Plan (SWMP) is required by the City of Carlsbad for all Development and Redevelopment Projects, pursuant to the City of Carlsbad Stormwater Management and Discharge Control Ordinance (Municipal Code Section 15.12). The purpose of this SWMP is to address the water quality impacts from the proposed La Costa Vista development. The site design, source control and treatment control Best Management Practices (BMPs) will be utilized to provide long term solution to protecting water quality. May 13,2013 Page 5 La Costa Vista - Storm Water Management Plan 2.0 APPLICABILE STORM WATER STANDARDS AND PROJECT TYPE Based on the criteria established in Order R9-2007-0001 NPDES No. CAS0108758 Section D.1, and review of the City's Standard Urban Stormwater Management Plan and after completion of the City of Carlsbad's Storm Water Standards Questionnaire (E-34) for New Development and Redevelopment Projects, the proposed project is identified as a Priority Development Project. Since the proposed project has been identified as a Priority Project, this SWMP includes design and supporting calculations for site design Low Impact Development (LID) BMPs, Source Control BMPs, Treatment Control BMPs, and hydromodification. Project was evaluated for exemption from hydromodification but determined that the project was not eligible for exemption since the storm drain on Jerez Court outlets to a natural water course. Brown and Coldwell BMP Calculator was used for threshold of Q2 x 0.10. May 13, 2013 Page 6 La Costa Vista - Storm Water Management Plan 3.0 PROJECT OVERVIEW 3.1 Project Location The project site is located in the City of Carlsbad on the northerly terminus of Jerez Court at 7500 Jerez Court, APN 216-290-09. Figure 3.1 illustrates the project location. The Tentative Map includes the project details, as further discussed in this section. Figure 3.1 ^ VICINITY MAP NORTH 3.2 Project Description The proposed La Costa Vista project is a private 7-unit airspace condominium project. The project has a total of 2 guest parking spaces and 1 handicap space. To conform to LID requirements for BMPs, the project utilizes the use of flow through planters and bioretention. The existing site is a vacant lot. The property is surrounded to the north and south by multifamily development and by a golf course to the west. The detailed single sheet post-construction BMP exhibit is included as Appendix A. 3.3 Project Size The project is located on a 0.41 acre site. The total disturbed area of the site is 0.41 acres. The project will be built in one phase. 3.4 Impen/ious and Pen/ious Surface areas The existing site is approximately 100% pervious. The proposed development after completion will be about 75% impervious. The project will result in an increase in impervious area from existing to final development conditions. Various treatment facilities like settling basins, wet ponds, media filters, higher-rate biofilters, and higher- rate media filters were considered but not found feasible because of the restraints presented by the site. Bioretention and permeable pavers were finally selected as the treatment devices. May 13,2013 Page 7 La Costa Vista - Storm Water Management Plan 4.0 PROJECT SITE ASSESSMENT This section includes information used to consider the potential water quality and hydrologic impacts from the proposed project. This information is important when considering the appropriate BMPs to reduce identified potential impacts as well as when designing low impact development (LID), source control and treatment control measures to reduce those impacts. Constraints presented by high density land use eliminated the use of urban green biofilter, vegetated swales, wetlands/wetponds. Use of flow through planters and bioretention and vault provided the opportunity to filtrate and treat the pollutants as well as control the release of stored water. 4.1 Land Use and Zoning The existing land use on the project is RD-M. 4.2 Existing Topography The existing site is fairly flat and draws from north to south. The site has no definite drainage pattem. 4.3 Existing and Proposed Drainage The existing site drains easterly in an uneven fashion towards the cul-de-sac. The proposed drainage system consists of concrete gutter, drain inlets and drain pipes which outlet to flow through planters and bioretention with vault. 4.4 Watershed and Receiving Waters The proposed project is located within the Carlsbad (HU 904) watershed or hydrologic unit and the subwatershed San Marcos HA 904.5. The surface and groundwater receiving waters located in the area and downstream of this project include Batiquitos HSA. The designated beneficial uses of these waters include MUN, AGR, RECI. REC2, IND, PROC, GWR, FRSH, NAV, POW and COMM. 4.5 303(d) Listed Receiving Waters The receiving water body for the project is San Marcos Creek and Batiquitos HSA and the ultimate receiving body is Pacific Ocean. The receiving water is impaired per CWA Section 303(d) for the following pollutants. San Marcos Creek: DDE, phosphorous, sediment toxicity, bacteria, nutrients and sediments. May 13,2013 Page 8 La Costa Vista ~ Storm Water Management Plan 4.6 Total Maximum Daily Loads (TMDLs) Hydrologic Descriptor Water Quality Limited Segment Nutrients/ Eutrophication Sedimentation/ Siltation TDS Bacteria Lower Ysidora HSA (902.11) Santa Margarita Lagoon Yes Loma Alta HA (904.10) Loma Alta Slougti Yes Yes Loma Alta HA (904.10) Pacific Ocean Shoreline at Creel< Yes El Salto HSA (904.21) Buena Vista Lagoon Yes Yes Yes Buena Vista Creek HA (904.20) Pacific Ocean Stioreline at Creel< Yes * Batiquitos HSA (904.51) San Marcos Greel< Yes Yes Los Monos HSA (904.31) Lower Agua Hedionda Creel< Yes San Elijo HSA (904.61) San Elijo Lagoon Yes Yes Yes Escondido Creel< HA (904.60) Pacific Ocean Shoreline at Lagoon Yes Miramar Reservoir HA Los Penasquitos Lagoon Yes Missbn San Diego HSA (907.11) Famosa Slough & Channel Yes 4.7 Soil Type(s) and Conditions A soils report prepared by Strata-Tech, Inc. dated February 19, 2011 indicates that the native soil consisted of black clay to brown clayey silt soil to a maximum depth explored of 10 feet. There was no ground water encountered up to a depth of 10 feet. May 13, 2013 Page 9 La Costa Vista - Storm Waler Management Plan 5.0 POLLUTANTS OF CONCERN Per Table 2-1 of City SUSMP, the potential storm water or urban runoff pollutants expected to be associated with this project, an attached residential development and parking lot are: • Bacteria and Viruses: Anticipated sources include animal excrement (found in areas where pets are often walked), sanitary sewer overflow and trash container handling areas. • Oil and Grease: Potential sources of oil and grease include motor vehicles. • Oxygen-Demanding Substances: Potential sources include biodegradable organic materials and various household chemicals, which deplete dissolved oxygen levels in water courses. Anticipated storm water or urban runoff pollutants expected to be associated with the project are: Sediment: Landscape areas and roof-tops are expected to be common sources of sediment due to erosion and wear. Nutrients: Nutrients, including nitrogen, phosphorus and other compounds can be anticipated to be generated by organic litter, fertilizers, food waste, sewage and sediment. Metals: Potential sources of trace metals (copper, lead, cadmium, chromium, nickel and zinc) include motor vehicles, re-roofing and hardscape/construction materials, and chemicals. Pesticides: Sources of pesticides include household bug spray, weed killers and other household sources. Trash and Debris: These sources include common litter, biodegradable organic matter such as leaves, grass cuttings and food wastes from landscaped areas and homeowners. 5.1 Project Categories and Features The project is an attached residential development. 5.2 Project Watershed Information The proposed project is located within the Carlsbad (HU 904) watershed or hydrologic unit and the subwatershed San Marcos HA 904.5. The Carlsbad Hydrologic Unit (HU) 4.00 is approximately 210 square miles extending from the headwaters above Lake Wolhford in the east to the Pacific Ocean in the west, and from Vista and Oceanside in the north to Solana Beach, Escondido, and the community of Rancho Santa Fe to the south. The cities of Carlsbad, San Marcos, and Encinitas are entirely within this HU. There are numerous important surface hydrologic features within the Carlsbad HU including 4 unique coastal lagoons, 3 major creeks, and 2 large water storage reservoirs. The HU contains four major coastal lagoons. From north to south they are Buena Vista (901.2), Agua Hedionda (904.3), Batiquitos (904.5), and San Elijo (904.6) HAs. There are other HAs and HSAs in the project area as listed on following chart May 13, 2013 PagelO La Costa Vista - Storm Water Management Plan BASIN NUMBER HYDROLOGIC BASIN BASIN NUMBER HYDROLOGIC BASIN 4.00 CARLSBAD HYDROLOGIC UNIT 4.10 Loma Alta HA 4.50 San Marcos HA 4.20 Buena Vista Creek HA 4.51 Batiquitos HSA 4.21 EISallD HSA 4.52 Richland HSA 4.22 Vista HSA 4.53 Twin Oaks HSA 4.30 Agua Hedionda HA 4.60 Escondido Creek HA 4.31 Los Monos HSA 4.61 San Elijo HSA 4.32 Buena HSA 4.62 Escondido HSA 4.40 Encinas HA 4.63 Lake Wohlford HSA 5.3 Hydromodification See calculations in Appendix F. May 13, 2013 Page 11 La Costa Vista - Storm Water Management Plan 6.0 BEST MANAGEMENT PRACTICES (BMPs) Minimizing the proposed project's effects on water quality, as well as compliance with State and local requirements can be most effectively achieved by using a combination of BMPs which include Low Impact Design (LID) Site Design, Source Control, and for Priority projects, Treatment Control measures. These design and control measures employ a multi-level strategy. The strategy, which is detailed in the City's Stormwater Standards Manual Section 4 of SUSMP, consists of: 1) reducing or eliminating post-project runoff; 2) controlling sources of pollutants; and 3) treating stormwater runoff before discharging it to the storm drain system or to receiving waters. This SWMP and the proposed BMPs for the proposed project have been developed to minimize pollutant impacts identified in Section 5 of this report and the introduction of pollutants identified in Section 2 of City's SUSMP, into the municipal storm drain system and/or ultimate drainage receiving waterbody. 6.1 LID Site Design Strategies and BMPs Conceptually, there are four LID strategies for managing runoff from buildings and paving: 1. Optimize the site layout; 2. Use pervious surfaces; 3. Disperse runoff; and 4. Design Integrated Management Practices (IMPs). 6.1.1 Optimize the Site Layout The development has incorporated by design, reduced street widths to reduce the amount of impervious area. The project also includes multi-level units to reduce the amount of runoff and reduce overall footprint. Impervious area has been substantially reduced by use of Eco-Stone pervious pavers in the driveway. As part of the design of all common area landscape areas, similar planting material with similar water requirements will be used to reduce excess irrigation runoff and promote surface filtration. 6.1.2 Flow Through Planters and Bioretention with Vault Flow through planters and bioretention with vault will be used to retain runoff. 6.1.3 Disperse Runoff The runoff from flow through planters and bioretention with vault is dispersed to curb outlet and catch basin via PVC drain pipe. 6.1.4 Integrated Management Practices (IMPs) BMPs used for the project are flow through planters and bioretention with vault. May 13.2013 Page 12 La Costa Vista - Storm Water Management Plan 6.2 Source Control BMPs It is anticipated that the following pollutants will be generated at this site: Sediment: Landscape areas and roof-tops are expected to be common sources of sediment due to erosion and wear. Nutrients: Nutrients, including nitrogen, phosphorus and other compounds can be anticipated to be generated by or founding organic litter, fertilizers, food waste, sewage and sediment. Metals: Potential sources of trace metals (copper, lead, cadmium, chromium, nickel and zinc) include motor vehicles, re-roofing and hardscape/construction materials, and chemicals. Pesticides: Sources of pesticides include household bug spray, weed killers and other household sources. Trash and Debris: These sources include common litter, biodegradable organic matter such as leaves, grass cuttings and food wastes from landscaped areas and homeowners. Based on these anticipated pollutants and operational activities at the site the following Table 6-1 summarizes the Source Control BMPs to be installed and/or implemented onsite. May 13, 2013 PaQe^3 La Costa Vista - Storm Water Management Plan TABLE 6-1 Stormwater Pollutant Sources/Source Control Checklist How to use this worksheet. 1. Review Column 1 and identify which of these potential sources of stormwater pollutants apply to your site. Check the box that applies. 2. Review Column 2 and incorporate all of the corresponding applicable BMPs in your project-specific SUSMP drawings. 3. Review Columns 3 and 4 and incorporate all of the corresponding applicable permanent controls and operational BMPs in a table in your Project-Specific SUSMP. Use the format shown in Appendix 1 of SUSMP. Describe your specific BMPs in an accompanying narrative and explain any special conditions or situations that required omitting BMPs or substituting alternatives. IF THESE SOURCES WILL BE ON THE PROJECT SITE... ...THEN YOUR STORMWATER CONTROL PLAN SHOULD INCLUDE THESE SOURCE CONTROL BMPs 1 Potential Sources of Runoff Pollutants 2 Permanent Controls-show on SUSMP drawings Permanent Controls-List in SUSMP Table and Narrative Operational BMPs-lnclude in SUSMP Table and Nan-ative A. On-site storm drain inlets Location of inlets. 1^ Mark all inlets with the words "No Dumping! Drains to Creek" or similar. Maintain and periodically repaint or replace inlet markings Provide stormwater pollution prevention information to new site owners, lessees, or operators. See applicable operational BMPs in Fact Sheet SC-44,"Drainage System Maintenance," in CASQA Stormwater Quality Handbooks at www.cabmphandbooks.com Include the following in lease agreements: "Tenant shall not allow anyone to discharge anything to storm drains or to store or deposit materials so as to create potential discharge to storm drains." 02. Landscape/ outdoor pesticide use Manage landscape and irrigation procedures and management of use of fertilizers and pesticides. 1^ Monthly during regular maintenance. G. Refuse Areas N. Fire Sprinkler Test Water P. Parking Lots and Sidewalks May 13, 2013 Page 14 La Costa Vista - Storm Water Management Plan 6.3 Treatment Control BMPs Given below is the basis of selection of use of flow through planters and bioretention with vault as BMPs and the related calculations. 6.3.1 Selection Various BMPs including modular wetland system, urban green biofilter and wetlands/wetponds were considered for the facility but not found feasible because of the following reasons. 1. The natural terrain is not suitable for wetlands. Also the existing ground is not suitable for it. 2. Bioretention facilities, settling basins and higher-rate biofilters were not considered suitable for the site due to the high density land use and development leaving unsuitable amount of area for such BMPs. TaWe 6-2 provides a general comparison of how various types of treatment facilities perform for each group of pollutants. The pollutants for the proposed project are identified in Section 5. TABLE 6-2 Groups of Pollutants and Relative Effectiveness of Treatment Facilities. Bioretention Facilities (LID) Settling Basins (Dry Ponds) Wet Ponds and Constructed Wetlands Flow Through Planters (LID) Media Filters Higher-Rate Biofilters Higher- Rate Media Filters Trash Racks & Hydro -dynamic Devices Vegetated Swales Pollutant of Concem: Coarse sediment and trash High High High High High High High High High Pollutant of Concern: Pollutants that tend to associate with fine particles during treatment High High High High High Medium Medium Low Medium Pollutant of Concern: Pollutants that tend to be dissolved following treatment Medium Low Medium High Low Low Low Low Low Based on this, the following facility has been selected for the proposed project: • Bioretention with vault and flow through planters were selected for the project because not only do they conform to LID requirements; they also allow reduction of volume and peak flows and filtering of pollutants. Impermeable liners will not allow recharge. The Geotechnical report included as Appendix C of this report indicates that the ground water is 10 feet or greater below any BMPs. 6.3.2 Design and Sizing The selected BMP will provide adequate treatment. Calculations for selected BMP are included in Appendix F. May 13, 2013 Page 15 La Costa Vista - Storm Water Management Plan 7.0 PROJECT PLAN{s) & BMP LOCATION MAP A BMP map included as Appendix A, illustrates the BMPs that will be implemented as described in Section 6 of this Storm Water Management Plan. May 13, 2013 Page 16 La Costa Vista - Storm Water Management Plan 8.0 BMP MAINTENANCE 8.1 Facility Ownership & Maintenance Agreements The following individual(s)/organization will own the facilities, including all structural and non-structural BMPs, and are responsible for maintenance in perpetuity: TMS Jerez Investments, LLC 19196 Sierra Isabelle Irvine, CA 92603 Contact Person: Tony Sfreddo 951.801.0888 8.2 Operations, Maintenance and Inspection 8.2.1 Typical Maintenance Requirements Flow-Through Planters: Inspect plants and structural components periodically. Maintenance is similar for all container plantings. Other maintenance needs may include removing sediment, cleaning and repairing pipes, and maintaining proper drainage. Downspouts, curb cuts, and other features where debris may obstruct flow must be inspected and cleaned periodically. Bioretention with Vault: Periodic scheduled inspections with a specified checklist, and inspections after major rainfall events, to check for obstructions/damage and to remove debris/trash. Mowing on a regular basis to prevent erosion or aesthetic problems. Limited use of fertilizers and pesticides in and around the bioretention with vault to minimize entry into bioretention with vault and subsequent downstream waters. Removal of any trash, etc. causing obstructions at the inlet, outlet, orifice or trash rack during periodic inspections and especially after every runoff producing rainfall event. General pickup of trash in and around the bioretention with vault during all inspections. 8.2.2 Operation and Maintenance (O&M) Plan An O&M Plan is included in the SWMP, refer to Table 8-1 on page 19. 8.2.3 Project BMP Verification The applicant's Engineer of Record must verify through inspection of the site that the BMPs have been constructed and implemented as proposed in the approved SWMP. The inspection must be conducted and City approval must be obtained prior to granting a certificate of occupancy. This approval may be verified through signatures on the as-built plans, specifically on the BMP sheet. 8.2.4 Annual BMP Operation and Maintenance Verification The BMP owner must verify annually that the O&M Plan is being implemented by submitting a self- certification statement to the City. The verification must include a record of inspection of the BMPs prior to the rainy season (October l^t of each year). May 13, 2013 Page 17 La Costa Vista - Storm Water Management Plan '1 certify that, as owner of the property described herein, I have read and understand the requirements of this Storm Water Management Plan (SWMP) and that I am responsible for ensuring that all storm water treatment measures described within said SWMP will be properly implemented, monitored and maintained." Investme a limited liability company Date May 13, 2013 Page 18 La Costa Vista - Storm Water Management Plan TABLE 8-1 Operation and Maintenance Plan BMP Applicable? Yes/No BMP Name and BMP Implementation, Maintenance, and Inspection Procedures Implementation, Maintenance, and Inspection Frequency and Schedule Person or Entity with Operation & Maintenance Responsibility Non-Structural Source Control BMPs Yes N1. Education for Property Owners, Tenants and Occupants HOA will insure that all homeowners will be given a copy of the recorded CC&Rs, which will contain a section outlining the environmental awareness education materials. The HOA will establish requirements for the implementation of a community awareness program that informs home buyers of the impacts of dumping oil, paints, solvents or other harmful chemicals into the storm drain; the proper use and management of fertilizers, pesticides and herbicides in home landscaping and gardening practices; the impacts of littering and improper watering. Environmental awareness education materials will be provided to all property owners/tenants. La Costa Vista HOA Yes N2. Activity Restriction Within the CC&Rs language will be included to identify surface water quality protection required by HOA. Surface water quality activities will also be conducted in conformance with the SWMP as it relates to the handling and disposal of contaminants. La Costa Vista HOA Yes N3. Common Area Landscape Management Monthly during regular maintenance, manage landscaping in accordance with Carlsbad Landscape Manual and with management guidelines for use of fertilizers and pesticides. La Costa Vista HOA Yes N4. BMP Maintenance Inspect prior to rain season, October 1='. Actual maintenance intervals to be established once system has been in operation and the rate of silt and/or debris accumulated can be qualified. La Costa Vista HOA No N5. Title 22 CCR Compliance Not applicable to the project. No N7. Spill Contingency Plan Not applicable to the project. No N8. Underground Storage Tank Compliance Not applicable to the project. No N9. Hazardous Materials Disclosure Compliance Not applicable to the project. No N10. Uniform Fire Code Implementation Not applicable to the project. Yes N11. Common Area Litter Control Weekly sweeping and trash pick within landscape areas and outside walkways La Costa Vista HOA May 13, 2013 Page 19 La Costa Vista - Storm Water Management Plan BMP Applicable? Yes/No BMP Name and BMP Implementation, Maintenance, and Inspection Procedures Implementation, Maintenance, and Inspection Frequency and Schedule Person or Entity with Operation & Maintenance Responsibility Yes N12. Employee Training HOA through in-house seminars will provide monthly training for both maintenance personnel and employees. HOA shall be responsible for providing homeowners/tenants with educational materials regarding the impact of dumping oil, paints, solvents or other potentially harmful chemicals into storm drains; the proper use of fertilizer and pesticides in landscaping maintenance practices; and the Impacts of littering and improper waste disposal. La Costa Vista HOA No N13. Housekeeping of Loading Docks Not applicable to the project. Yes N14. Common Area Catch Basin Inspection Once a month to clean debris and silt of basins. Intensified around October 1^' of each year prior to 'first flush" storm. La Costa Vista HOA Yes N15. Street Sweeping Private Streets and Parking Lots Vacuum cleaning once a year. La Costa Vista HOA No N17. Retail Gasoline Outlets Not applicable to the project. structural Source Control BMPs Yes Provide Storm Drain System Stenciling and Signage Once every three months Inspect for re-stenclling needs and re-stencll as necessary. La Costa Vista HOA No Design and Construct Outdoor Material Storage Areas to Reduce Pollutant Introduction Not applicable to the project. No Design and Construct Trash and Waste Storage Areas to Reduce Pollutant Introduction Not applicable to the project. Yes Use Efficient Irrigation Systems & Landscape Design Once a week in conjunction with maintenance activities. Verify runoff minimizing landscape design continues to function by checking that water sensors are functioning properly, irrigation heads are adjusted properly to eliminate overspray to hardscape, and to verify that irrigation timing and cycle lengths are adjusted in accordance with water demands, given time of year, weather, and day or night temperatures. La Costa Vista HOA No Protect Slopes and Channels and Provide Energy Dissipation Not applicable to the project. May 13, 2013 Page 20 La Costa Vista - Storm Water Management Plan BMP Applicable? Yes/No BMP Name and BMP Implementation, Maintenance, and Inspection Procedures Implementation, Maintenance, and Inspection Frequency and Schedule Person or Entity with Operation & Maintenance Responsibility No Loading Docks Not applicable to the project. No Maintenance Bays Not applicabie to the project. No Vehicle Wash Areas Not applicable to the project. No Outdoor Processing Areas Not applicable to the project. No Equipment Wash Areas Not applicable to the project. No Fueling Areas Not applicable to the project. No Hillside Landscaping Not applicable to the project. No Wash Water Controls for Food Preparation Areas Not applicable to the project. No Community Car Wash Racks Not applicable to the project. Treatment Control BMPs Yes Treatment Control BMP Permeable Pavers and Flow Through Planters Permeable Pavers: Periodic clearing and vacuum cleaning, once a year. Flow Through Planters: 1 to 4 times a year determined by accumulation of sediments. La Costa Vista HOA Yes Bioretention Twice annually or after heavy rain events. La Costa Vista HOA May 13, 2013 Page 21 APPENDIX A BMP Plan APPENDIX B Grading Plan APPENDIX C Soils Report STRATA-TECH, INC. SEOCDNSULTANTS 7372 Walnut Avenue, Unit F.Buena Park, Califomia 90620 SEOCDNSULTANTS FAX 714-521-2552 February 19,2011 W.O. 263810 Tony Sfredo 21 Woodcrest Irvine, Califomia, 92603 Subject: Geotechnical Engineering Investigation of Proposed Multi Family Residential Development, 7500 Jerez Court, Carlsbad, Califomia. Gentlemen: Pursuant to your request, a geotechnical investigation has been performed at the subject site. The purposes ofthe investigation were to determine the general engineenng charactenstics of the soils on and underlying the site and to provide recommendations for the design of foundations, pavements and underground improvements. PROPOSED DEVELOPMENT It is our understanding that the proposed development will consist of approximately 7 attached town homes of wood-framed constmction with parking and landscapmg. PURPOSE AND SCOPE OF SERVICES The scope ofthe smdy was to obtain subsurface infonnation within the project site area and to provide recommendations pertaining to the proposed development and mcluded the followmg: 1. A cursory reconnaissance ofthe site and sunounding areas. 2. Excavation of exploratory geotechnical test pits to detennine the subsurface soil and groundwater conditions. 3. Collection of representative bulk and/or undisturbed soil samples for laboratory analysis. 4 Laboratory analyses of soil samples including detennination of in-situ and maximum density, in-situ and optimum moisture content, shear strength and consolidation characteristics, expaasion potential and liquefaction analysis. 5. Preparation of this report presenting results of our investigation and recommendations for the proposed development. XRATA-TEC H , I N C EODONSULTANTS W. O. 263810 Tony Sfredo ^ Fehniarv 19.2011 Geotechnical F.ngineering Investigation .—. • SITE CONDITIONS The 115 bv 150 foot rectangular lot is located on the westem side ofthe Jerez Court Cul de sac Se i e ifshown on the attached vicinity Map, Plate No. 1. Two story wood frame dwellings exist nor^h mdZ2 ofthe site. A golf course exists on grade adjacent to the westem property line Ktou'l^rrl^^^^^^ Site configuration is fiirther illustrated on the Site Plan, Plate 2. FIELD INVESTIGATION groundwater at 10-feet. Description ofthe soils encountered are presented on the attached Test Pit Logs. The data nrS onl^logs is a simplification of actual subsurface conditions encountered and apphes onrrt^^^^ location and the dale excavated. It is not wananted to be representative of subsuiface conditions at other locations and times. EARTH MATERIALS soils. Native soils consisted of a silty residual sandy soil to a maxiinum depth explored of 10 feet in test pit 2. Groundwater was not encountered in any of our geotechnical pits. SEISMICITY Southem Califomia is located in an active seismic region. Moderate to sfrong earthquakes can Let on numtris. T^e United States Geological Survey ^frvfrrrtC"?^^ Genlnev orivate consultants, and universities have been studying earthquakes in Solem'calSa for several decades, l^e purpose oftiie code f^-^l'^^^^^^^^^^ prevent collapse during sfrong ground shaking. Cosmetic damage should be expected. TRATA-TEC H.I N C . EPCONSULTANTS W. 0.263810 Tony Sfredo Februarv 19.2011 Geotechnical Fnpineerine Investigation ., . _ The Drincipal seismic hazard to tiie subject property and proposed project is sfrong ground shaking eaZquZ^^ by local failts. Secondary effects such as surface mpfrire, lurching, or flooding are not considered probable. SEISMIC DESIGN VALUES NEHRP Seismic Design Provisions Site Class D - Fa = 1.05 ,Fv = 1.57 Spectol Response Accelerations Ss and SI = Mapped Specfral Acceleration Values Data are based on a 0.01 deg grid spacing Ss=L14 Si=0.43 Sa=.79 CONCLUSIONS AND RECOMMENDATIONS Development ofthe site as proposed is considered feasible firom a soils engineering standpoint, provteT^^^^^^ stated herein are incoijporated in the design and are implfmented in tiie field. Recommendations are subject to change based on review of final foundation and grading plans. It is recommended that the proposed structures be entirely supported by compacted fill A m n rnum 2-foot thick compacted fill blanket below the bottom of the footings . recon'^rnded. The over excavation requirement is 2 foot below footings, or 4 feet deep for 2 foot footings. If tiie pad grade is cut, tiien tiie bottom will have to be deeper For other minor sfructiires such as property line walls or retaining walls less than 4 feet high, competent native soils or compacted fill may be used for sfrucmral support. PROPOSED GRADING Gradina plans were not available at the time our work was performed. It is assumed that propos^ed'^ grades will not differ significantly from existing grades. The followmg recommendations are subject to change based on review of final grading plans. GRADING RECOMMENDATIONS Removal and recompaction of existing fill and loose native soils will be required to provi^^^ SLe support for foundations and slabs on grade. The deptii of removal shall be 1 foot below the bottom of the footings, which is estimated to be at least 3 feet bdow e-tmg^^^^^^^^ over excavation requirement is I foot below footings, or 3 feet deep for 2 foot footings. It pad grade is cut, then tiie bottom will have to be deeper IS STRATA-TEC H , I IM C EDCPNSULTANTS Tony Sfredo Geotechnical Engineering Investigation W.O. 263810 Febmary 19.2011 Earthwork for foundation support shall include the entire building pad and shall extend a minimum of 5 feet outside exterior footing lines where feasible or to property line. Care shall be exercised not to undermine hardscape, walls, or pavements that are located on adjacent properties. If removals extend to off site stmctures or concrete block perimeter walls that are located within 4-feet from the bottom excavation, then slot cutting or shoring will be required. The exposed excavation bottom shall be observed and approved by STRATA-TECH, Inc. and the City's grading inspector prior to processing. Dependent on field observations, removals may be adjusted up or down. Subsequent to approval of the excavation bottom, tiie area shall be scarified 6 inches, moisture conditioned as needed, and compacted to a minimum of 90 percent relative compaction. Fill soils shall be placed in 6 to 8 inch loose lifts, moisture conditioned as needed, and compacted to a minimum of 90 percent relative compaction. This process shall be utilized to finish grade. Grading for hardscape areas shall consist of removal and recompaction of soft surficial soils. Removal deptiis are estimated at 1 to 2 feet Earthwork shall be performed in accordance with previously specified methods. Grading and/or foundation plans shall be reviewed by tiie soil engineer. All recommendations are subject to modification upon review of such plans. FOUNDATIONS ON COMPACTED FILL The proposed building may be supported by continuous spread and isolated footings placed a minimum depth of 24 inches below lowest adjacent grade utilizing an allowable bearing value of 2,000 pounds per square foot This value is for dead plus live load and may be increased 1/3 for total including seismic and wind loads where allowed by code. Type Minimum Depth (inches) Minimum Width (inches) Bearing Value (psf) Increase Maximum (psf) Type Minimum Depth (inches) Minimum Width (inches) Bearing Value (psf) Widtii Depfli Maximum (psf) Type Minimum Depth (inches) Minimum Width (inches) Bearing Value (psf) (psfft) (psf7ft) Maximum (psf) Continuous 24 12 2000 180 440 3500 Interior Pad 18 24 2000 180 440 3500 It is recommended that all footings be reinforced witii a minimum of two no. 4 bars (1 top and 1 bottom). The structural engineer's reinforcing requirements should be followed if more stringent. if ITRATA-TEC H , I N C EOCONSULTANTS Tony Sfredo Geotechnical Engineering Investigation W. O. 263810 Febmary 19.2011 Footing excavations shall be observed by a representative of STRATA-TECH, Inc. prior to placement of steel or concrete to verify competent soil conditions. If unacceptable soil conditions are exposed mitigation will be recommended. FOUNDATIONS ON COMPETENT NATFV^E SOILS - for Minor Structures Minor structures may be supported by continuous spread footings placed a minimum depth of 24 inches below lowest adjacent grade and 12-inches into natural soil utilizing an allowable bearing value of 1,500 pounds per square foot. This value is for dead plus live load and may be increased 1/3 for total including seismic and wind loads where allowed by code. Footing excavations shall be observed by a representative of STRATA-TECH, Inc. prior to placement of steel or concrete to verify competent soil conditions. If unacceptable soil conditions are exposed, mitigation will be recommended. LATERAL DESIGN Lateral resfraint at tiie base of footings and on slabs may be assumed to be tiie product ofthe dead load and a coefficient of friction of .30. Passive pressure on die face of footings may also be used to resist lateral forces. A passive pressure of zero at tiie surfece of finished grade, mcreasing at the rate of 300 pounds per square foot of deptii to a maximum value of 2,500 pounds per square foot may be used for compacted fill or native soils at tiiis site. If passive pressure and friction are combined when evaluating tiie lateral resistance, tiie value of tiie passive pressure should be limited to 2/3 ofthe values given above. RETAINING WALLS Unrestiained walls up to 5-feet in height retaining drained earth may be designed for the following: Surface Slope of Retained Material Horizontal to Vertical Equivalent Fluid Pressure Pounds Per Cubic Foot Level 30 5 to I 32 4tol 35 3tol 38 2tol 43 These values include seismic loading. BackfiU should consist of clean sand and gravel. While all backfills should be compacted to tiie required degree, exfra care should be taken working c ose to walls to prevent excessive pressure. Retaining walls should include subdrains consisting of 4-inch SCH 40 or SDR 35 perforated pipe sunounded by 1 cubic foot per Imeal foot of cmshed rock. All wall bacMll should be compacted to a minimum of 90 percent relative compaction. STRATA-TECH, I N C EOCONSULTANTS TonySfredo 6 W. 0.263810 Geotechnical Engineering Investigation Februarv 19.2011 All retaining stmctures should include appropriate allowances for anticipated surcharge loading, where applicable. In this regard, a uniformly distributed horizontal load equal to one-half the vertical surcharge shall be applied when the surcharge is within a horizontal distance equal to the wall height Retaining wall footing excavations shall be founded entirely in competent native soils or compacted fill. Footing bottoms shall be observed by a representative of STRATA-TECH, Inc., to verify competent conditions. EXPANSrSHE SOILS Results of expansion tests indicate that the near surface soils have a low expansion potential. SETTLEMENT The maximum total post-constiuction settlement is anticipated to be on the order of 1/2 inch. Differential settlements are expected to be less than 1/2 inch, measured between adjacent stmctural elements. SUBSIDENCE & SHRINKAGE Subsidence over the site during grading is anticipated to be on the order of .5 feet. Shrinkage of reworked materials should be in the range of 10 to 15 percent. FLOOR SLABS The surface soils are non-plastic with low expansion potential. Where concrete slabs on grade are utilized, the slab shall be supported on at least 1 foot of engineered fill compacted to a minimum of 90 percent relative compaction. Slabs should be at least 4 inches thick and reinforced with a minunum of no. 3 b^^ 24 inches on center both ways. The soil should be kept moist prior to casting the slab. However, if the soils at grade become disturbed during constmction, they should be brou^t to approximately optimum moisture content and rolled to a firm, unyielding condition prior to placing concrete. In areas where a moisture sensitive floor covering will be used, a vapor banier consisting of a plastic film (6 ml polyvinyl chloride or equivalent) should be used. The vapor barrier should be properly lapped and sealed. Since the vapor barrier will prevent moisture from draining from fresh • STRATA-TEC H.I N C. EOCONSULTANTS W.O. 263810 TonySfredo . , . . Februarv 19.2011 Geotechnical Engmeermg; Investigation concrete, a better concrete finish can usually be obtained if at least 2 inches of wet sand is spread over the vapor barrier prior to placement of concrete. UTILITY LINE BACKFILLS All utility line backfllls, botii interior and exterior, shall be compacted to a minimum of 90 percent relative compaction and shall require testing at a maximum of 2-foot vertical mtervals. HARDSCAPE AND SLABS Hardscape and slab subgrade areas shall exhibit a minimum of 90 percent relative compaction to a depth of at least 1 foot. Deeper removal and recompaction may be required if unacceptable conditions are encountered. These areas require testing just prior to placing concrete. STORMWATER INFILTRATION TEST RESULTS Two Hand Dug test pits were excavated at 3-foot elevation in tiie bottom oftiie back hoe test pits. The diameter of the test hole was 6-inches. . u TU The lower depth of the pit exposed a natiiral soil layer of very dense brown sandy si t. The percolation test was perfonned by siphoning a 5-gallon water bottle into tiie hand-dug hole. The water level was kept at 5 to 6 inches in deptii for a period of four hours. At ti,e end of four hours the time for the water to drop from the 6* to tiie 5* inch was measured. This value was 105 minutes for both holes. • A t;^^ .^Ath The percolation rate can be expected to perfonn at tiie tested rate over a short penod oftime with clean water flowing into undisttirbed soil. A high fector of safety should be used for longer-term use with unfiltered water. The percolation rate can be expected to increase at a power of 1.5 with respect to head increase. DRAINAGE Positive drainage should be planned for tiie site. Drainage should be directed away from sfructures via non-erodible conduits to suitable disposal areas. Unlined flowerbeds, planters, and lawns should not be constiiicted against tiie perimeter ofthe stmcture. If such landscaping (against tiie perimeter of a sfructtire) is planned, it should be properiy drained and lined or piovided witii an underground moistiire bamer. frngation should be kept to a minimum. This report is issued witii tiie understanding ttiat it is tiie responsibility of tiie owner, or of his representative, to ensure tiiat tiie infonnation and recommendations contained herem are called to tiie attention ofthe engineers for tiie project and incorporated into tiie plans and tiiat the necessary TRATA-TEC H , I N C . E OCDNSULTANTS W. 0. 263810 Tony Sfredo February 19. 2011 Geotechnical Engineering Investigation . _ - steps are taken to see that the Confractors and Subconfractors cany out such recommendations in the field. ENGINEERING CONSULTATION, TESTING & OBSERVATION We will be pleased to provide additional input witii respect to foundation design once methods of constiuction and/or nature of imported soil has been detemuned. Grading and foundation plans should be reviewed by tiiis office prior to commencement of grading so tiiat appropriate recommendations, if needed, can be made. Areas to receive fill should be inspected when unsuitable materials have been removed and prior to placement of fill, and fill should be observed and tested for compaction as it is placed. AGENCY REVIEW All soil geologic and stmctiiral aspects oftiie proposed development are subject to tiie review and a™^^^^^ agency^. It should be recognized tiiat tiie goveming agency (s) can dSI tiie mamier in whL tiie project proceeds. They could approve or deny any aspect of the Ssed lirements and/or could dictote which foundation and grading options are acceptable. wS^^^^^ consulting in response to agency requests for additional infomiation could be required and will be charged on a time and matenals basis. LIMITATIONS This report presents recommendations pertaining to the subject site based on tfie assumption that tiie sSL conditions do not deviate appreciably from tiiose discbsed by our explorato^^ excavatLs. Our recommendations are based on the teclHii-»."-j;; ^^^^^^^ the proposed constmction, and our experience in tiie geotechmcal field. We do not ^^e peX^^e of Ae project, only tiiat o^engineering work and judgments meet tiie standard of care of our profession at this time. In view ofthe general conditions in tiie area, ttie possibility of different 1<^^1^^" ^^^^jj;^^^^^^ exis Aiiv deviation or unexpected condition observed during consfruction should be brought to lhem^onT±e Geoiechr^.l Engineer. In ttiis way, any supplemental recommendations can be made witii a minimum of delay necessary to ttie project If the proposed consfruction will differ from our present understanding ofthe project Ae existing nfLati^ and possibly new factors may have to be evaluated. Any design changes and the fmS Xurshould be reviewed by ttie Geotechnical Consultant Of particular importance would L fxirg development to new areas, changes in sfrucmral loading conditions, postponed development for more tiian a year, or changes m ownership. TRATA-TEC H , I IM C EOCONSULTANTS Tony Sfiredo Geotechnical Engineering Investigation W. O. 263810 Februarv 19.2011 This report is issued witii tiie understandmg tiiat it is tiie responsibttity of the owner, or of hs represeLtive, to ensure tiiat tiie infonnation and recommendations contained herem are called to hSSn oftiie Architects and Engineers for tiie prc,ject and incorporated into tiie plans and that lhe ^essar^ steps are taken to see tiiat tiie confractors and subconfractors cany out such recommendations in the field. This report is subject to review by ttie contirolling autiiorities for tiiis project We appreciate tiiis opportimity to be of service to you. Roland Acuna Principal Einiey Larry, RCE 46606 Enclosures: Plate 1: Vicinity Map Plate 2: Site Plan and Boring Location Map Test Pit Logs , ^ , w Appendix A: Laboratory Results and Engmeenng Calculations Appendix B: Specifications for Grading STRATA-TEC H , J IM kGEQCDNSULTANTB APPENDIX A This appendix contains a description of the field investigation, laboratory testing procedures and results, site plan, and exploratory logs. FIELD INVESTIGATION The field investigation was performed on January 19, 2011, consisting of tiie excavation of two exploratory trenches at locations shown on the attached Site Plan, Plate 2. As excavation progressed, personnel from this office visually classified the soils encountered, and secured representative samples for laboratory testing. Sample Retrieval- Backhoe Undisturbed samples of earth materials were obtained at frequent intervals by driving a thin- walled steel sampler by tiie hydraulic action of the backhoe bucket. The material was retained in brass rings of 2.41 inches inside diameter and 1.00 inch height. The cenfral portion oftiie sample was in close-fitting, watertight containers for fransportation to the laboratory. Descriptions of the soils encountered are presented on the attached boring Logs. The data presented on tiiese logs is a simplification of actiial subsurfece conditions encountered and applies only at the specific boring location and tiie date excavated. It is not warranted to be representative of subsuiface conditions at otiier locations and times. Laboratory Testing Field samples were examined in tiie laboratory and a testing program was tiien established to develop idata for preliminary evaluation of geotechnical conditions. Moisture Density Field moisture content and dry density were detennined for each of the undisturbed soil samples. The dry density was determined in pounds per cubic foot. The moisture content was determined as a percentage ofthe dry soil weight The results of the tests are shown in tiie test results section of this appendix. Compaction Character Compaction tests were performed on bulk sample of the existing soil in accordance with ASTM Dl 557-07. The results ofthe tests are shown in ttie test results section of this appendix. Shear Strength The ultimate shear strengtiis ofthe soil, remolded soil, highly weathered bedrock and bedrock was determined by performing direct shear tests. The tests were perfonned in a strain-controlled „STRATA-TECH, I IM C EOCONSULTANTS machine manufactured by GeoMatic. The rate of defomiation was 0.005 inches per minute. Samples were sheared under varying confining pressure, as shown on ttie "Shear Test Diagrams". The samples indicated as satiirated were artificially saturated in the laboratory and were shear under submerged conditions. The results of tests are based on 80 percent peak sfrengtii or ultimate strengtii, whichever is lower, and are attached. In addition, a shear was perfonned on an upper layer sample remolded to 90-percent oftiie laboratory standard witii low confining pressure. TEST RESULTS Maicitniim Densitv/ODtimum Moisture f ASTM;D-1557-07J Trench Depth in Feet Maximum Density (pcf) Optimum Moisture (%) 2 1-3 126 11.0 Tn-Situ Drv Densitv/ Moisture Trench Depth in Feet Dry Density (txf) Moisture 1 3.5 113.0 14.01 2 3 108.1 12.0 Direct Shear Trench Depth in Feet Cohesion (psf) Angle of Intemal Friction (degrees) 2 2 200 30 Proposed Pool PA ACTIVE RETAINING WALL PRESSURE H = Sft Hc= 2 ft 25 = 53.1 " F.S. = 2.00 yj0m= 130 pcf C = 200 psf ;? = 30° Free Bodv Diagram 0.13 kef 0.2 ksf C^L PA H 25 = 45°+ 12 W=a + b Cm = C/F.S. = 0.1 ksf x"m = tan'^ (tan x" / F.S.) 16.1 degrees D ( H - He ) tan ( 90° - G ) = 2.26 ft L = ((H-He)' + D')^''= 3.76ft I.Q3kips/LF a = Cm L Sin (90° + x"n,) / sin (S3 - x*m) = 0.6 kips/LF b = w-a= 0.43 kips/LF PA = b tan (25 - x"m) = 0.32 kips/LF DesignEFP = 2PA/H^= 25.6 pcf Use 26 pcf (30 min.) Geotechnical Engineering Invesfigation 75 00 Jerez Court Work Order 262310 Carlsbad, California STRATA - TECH, INC. ALLOWABLE BEARING CAPACITY Reference: "Soil Mechanics in Engineering Practice", Terzaghi and Peck, 1967 pages 222 and 223. Bearing Material: compacted fill Properties: Wet Density (g) = 130 pcf Cohesion (C) = 200 psf Angle of Friction (x'^) = 30 degrees Footing Depth (D) = 2 feet Footing Width (B) = 1.0 fbot Factor of Safety = 3.0 Calculations - Ultimate Bearing Capacity from figure 33.4 on page 222 Nc= 30.14 Nq= 18.4 N'^ = 22.4 0^,= 1.2CNc + vjoDNq + 0.4>)oBN (Square Footing) = 1.2*200*30.14+ 130*2*18.4 + 0.4*130*1 *22.4 = 7233 + 4784+1164=13181 psf Allowable Bearing Capacity for Square Footing Qji= Qu/F.S. = 4393 psf Use 1500 psf (Settlement Control) = 1.0 C Nc + >)o D Nq + 0.5 >)o B N (Continuous Footing) = 1.0*200*30.14+ 130*2* 18.4 + 0.5*130*1 *22.4 = 6028 + 4784 + 1456 = 12268 psf Allowable Bearing Capacity for Continuous Footing QaN= Qu/F.S. = 4089 psf Use 1500 psf (Settlement Control) Increases: 440 psf / ft in depth over 2 feet 0 psf / ft in depth over 1 foot Geotechnical Engineering Investigation Work Order 262310 7500 Jerez Court Carlsbad, California STRATA' TECH, INC. .STRATA-TEC H , I IM EQCDNSULTANTS APPENDIX B SPFCIFICATTONS FOR GRADING SITE CLEARING All existing vegetation shall be stiipped and hauled from tiie site. PREPAEATION After the foundation for tiie fill has been cleared, plowed or scarified, it shall be disced or bladed until it is unifomi and free from large clods, brought to a proper moistiire content and compacted to not less than 90 percent oftiie maximum dry density in accordance witii ASTM:D-l 557-02 (5 layers - 25 blows per layer; 10 Ib. hammer dropped 18"; 4" diameter mold). MATERIALS On-site materials may be used for fill, or fill materials shall consist of materials approved by the Soils Engineer and may be obtained from tiie excavation of banks, bonow pits or any other approved source. The materials used should be free of vegetable matter and otiier deletenous substances and shall not contain rocks or lumps greater tiian 8 inches in maximum dimension. PLACING, SPREADING, AND COMPACTING FILL MATERIALS Where natiiral slopes exceed five horizontal to one vertical, ttie exposed bedrock shall be benched prior to placing fill. The selected fill material shall be placed in layers which, when compacted, shall not exceed 6 inches hi ttiickness. Each layer shall be spread evenly and shall be ttioroughly mixed dunng the spreading to ensure unifonnity of material and moistiire of each layer. Where moistiire of ttie fill material is below ttie limits specified by tiie Soils Engineer, water shall be added until the moisture content is as required to ensure thorough bonding and thorough compaction. Where moishire content oftiie fill material is above tiie limits specified by tiie Soils Engineer, tiie fill materials shall be aerated by blading or otiier satisfactory metiiods until tiie moistiire content is as specified. After each layer has been placed, mixed and spread evenly, it shall be ttioroughly compacted to not less tiian 90 percent oftiie maximum dry density in accordance witii ASTM:D-1557-02 (5 layers - 25 blows per layer; 10 Ibs. hammer dropped 18 inches; 4" diameter mold) or otiier density tests which will attain equivalent results. STRATA-TEC H , I IM C EOCONSULTANTS Compaction shall be by sheepsfoot roller, multi-wheel pneumatic tire roller or other types of acceptable rollers. Rollers shall be of such design that ttiey will be able to compact the fill to the specified density. Rolling shall be accomplished while the fill material is at the specified moishire content. Rolling of each layer shall be continuous over the entire area and the roller shall make sufficient trips to ensure ttiat tiie desired density has been obtained. The final surface of the lot areas to receive slabs on grade should be rolled to a dense, smooth surface. The outside of all fill slopes shall be compacted by means of sheepsfoot rollers or otiier suitable equipment. Compaction operations shall be continued until the outer 9 inches of the slope is at least 90 f lercent compacted. Compacting of ttie slopes may be progressively in increments of 3 feet to 5 feet of fill height as tiie fill is brought to grade, or after the fill is brought to its total height. Field density tests shall be made by the Soils Engineer of the compaction of each layer of fill. Density tests shall be made at intervals not to exceed 2 feet of fill height provided all layers are tested. Where the sheepsfoot rollers are used, ttie soil may be disturbed to a depth of several inches and density readings shall be taken in tiie compacted material below the disturbed surface. When these readings indicate tiiat ttie density of any layer of fill or portion there is below the required 90 percent density, tiie particular layer or portion shall be reworked until the required density has been obtained. The grading specifications should be a part of tiie project specifications. The Soil Engineer shall review the grading plans prior to grading. INSPECTION The Soil Engineer shall provide continuous supervision of the site clearing and grading operation so that he can verify the grading was done in accordance with the accepted plans and specifications. SEASONAL LIMFTATIONS No fill material shall be placed, spread or rolled during unfavorable weather conditions. When work is intermpted by heavy rains, fill operations shall not be resumed until tiie field tests by the Soils Engineer indicate the moistiire content and density of the fill are as previously specified. EXPANSB^SOIL CONDITIONS Whenever expansive soil conditions are encountered, the moisture content of the fill or recompacted soil shall be as recommended in the expansive soil recommendations included herewith. APPENDIX D Hydrology Study Hydrology Study La Costa Vista Project No. CT 11-02 Carlsbad, California (Dwg No. 477-7A) Prepared For: TMS, JEREZ INVESTMENTS, LLC 19196 Sierra Isabelle Irvine, California 92603 Prepared By: Surender Dewan, P.E. DMS Consultants, Inc. 12371 Lewis Street, Suite 203 Garden Grove, California 92840 714.740.8840 June 06, 2013 CONSULTANTS, INC. CIVIL ENGINEERS 1 I Page JEREZ COURT CARLSBAD Site Description The proposed project is located in the City of Carlsbad at the terminus of Jerez Court @ 7500 Jerez Court on a 0.41 acre site. The proposed project is a 7-unit airspace condominium project. Purpose The purpose of this study is to determine the total runoff generated for a storm of six (6) hour duration for one hundred (100) year frequency and design an infiltration system to store the increase in volume of runoff between the pre and post runoff condition. 2 I P a g e Section 1.0 100 Year Hydrology Calculations 1.1 Rainfall The 100 year 6 hr rainfall depth was tal<en from the San Diego County Hydrology IVlanual isopluvial maps. Figure 1 below is an enlarged copy ofthe applicable section ofthe map. 1.1.1 Existing Condition Rainfall Rainfall for the existing condition was taken from the Manual. 1.1.2 Proposed Condition Rainfall The total 100 year storm depth for the proposed condition was calculated by subtracting the Water Quality Depth (see below) from the 100 year storm from the IVlanual. 4 .-I^XAy-' Figure 1100 Year 6hr Isopluvials 1.2 Soil Type The hydrologic soil type for the area of the proposed tract is listed as "C in the IVlanual Appendix A. Runoff Coefficients Runoff coefficients for the pre and post project condition were taken from Table 3-1 of the Hydrology Manual. (See attached table 3-1.) 1.3 Time of Concentration (Tc) 1.3.1 Existing Condition Tc The lot currently drains, via overland flow, to the southeast with an average slope of 2%. The initital time of concentration (Ti) was estimated using Table 3-2 of the Hydrology Manual (See attached Table 3-2). The Tt for the rest of the flow distance was estimated using Manning's equation assuming a broad open CARLSBAD Figure 2 Soil Type swale with a 20:1 side slope to calculate the flow velocity. See the attached hydraulic calculations for the swale travel time. These values were entered into an Excel spreadsheet that calculates the Tc and the corresponding I per the equation on Section 3 page 7 of 26. 1.3.2 Proposed Condition Tc In the proposed condition the lots drain to a concrete swale in the center of the tract which conveys the flows via inlet to onsite landscape areas. The initial Ti was estimated using Table 3-2 ofthe Hydrology Manual. The velocity in the swale was estimated using Manning's equation and the velocity in the pipe was calculated using V = Q/A and assuming the pipe will be flowing full. These values were entered into an Excel spreadsheet that calculates the Tc and the corresponding I per the equation on Section 3 page 7 of 26. 1.3.3 Conclusion Table A gives the pre and post project runoff for the four subareas on the site.The 100 year 6 hr flow rate in the existing condition is 0.46 cfs and the proposed flow rate is 1.27 cfs for an increase from the site of 0.81 cfs. Hydraulic Evaluation Summary - TABLE A Subarea Pre-Project Post-Project C 1 A Q C 1 A Q Difference (in/hr) (acres) (cfs) (in/hr) (acres) (cfs) (cfs) A 0.30 3.15 0.070 0.07 0.69 3.87 0.070 0.19 0.12 B 0.30 3.77 0.050 0.06 0.69 3.77 0.050 0.15 0.09 C 0.30 3.27 0.130 0.13 0.69 4.33 0.130 0.39 0.26 D 0.30 3.36 0.210 0.21 0.69 3.81 0.210 0.55 0.34 Total 0.46 1.27 0.81 4 I P a R (: ICQ Year Hydrology Calculations for Jerez Townhomes Area A Site Data Value Units Graded Area 3049.2 sf Soil Group C Pre Project Runnoff Coefficient "C" 0.30 Post Project Project Runnoff Coefficient "C" 0.69 Pre Project 100 vear 6hr Runoff Pre Project Ti 10.90 min Earth Swale Length 150.00 ft Earth Slope 0.02320 percent Earth Swale Z 20.00 Earth Swale N 0.025 Earth Swale Flow Depth 0.100 ft Earth Swale Velocity 0.34 ft/sec Earth Swale Tt 7.31 min Tc = Ti + Tt 18.21 min 100 year 6 hr Depth 2.75 in 100 year 6 hr intensity 3.15 in/hr 100 Year flow rate 0.07 cfs Post Proiect 100 year 6hr Runoff Post Project Ti 5.10 min Length 120.00 ft Slope 0.095 percent Swale Z 50.00 Swale N 0.02 Swale Flow Depth 0.086 ft Swale Velocity 0.52 ft/sec Swale Tt 3.88 min Tc 8.98 min 100 year 6 hr Depth 2.75 in Infiltration Depth (See Storm Water Calculations) 0.61 in Effective 100 6hr Depth 2.14 in 100 year 6 hr intensity 3.87 in/hr Graded Area 3049.20 ft'^2 ICQ Year flow rate 0.19 cfs ICQ Year Hydrology Calculations for Jerez Townhonnes Area B Site Data Value Units Graded Area 2178 sf Soil Group C Pre Project Runnoff Coefficient "C" 0.30 Post Project Project Runnoff Coefficient "C" 0.69 Pre Proiect 100 vear 6hr Runoff Pre Project Ti 10.90 min Earth Swale Length 150.00 ft Earth Slope 0.02320 percent Earth Swale Z 20.00 Earth Swale N 0.025 Earth Swale Flow Depth 0.059 ft Earth Swale Velocity 0.86 ft/sec Earth Swale Tt 2.89 min Tc = Ti + Tt 13.79 min 100 year 6 hr Depth 2.75 in 100 year 6 hr intensity 3.77 in/hr 100 Year flow rate 0.06 cfs Post Proiect 100 vear 6hr Runoff Post Project Ti 5.10 min Length 78.00 ft Slope 0.015 percent Swale Z 50.00 Swale N 0.02 Swale Flow Depth 0.078 ft Swale Velocity 0.48 ft/sec Swale Tt 2.69 min Tc 7.79 min 100 year 6 hr Depth 2.75 in Infiltration Depth (See Storm Water Calculations) 0.61 in Effective 100 6hr Depth 2.14 in 100 year 6 hr intensity 4.24 in/hr Graded Area 2178.00 ft'^2 100 Year flow rate 0.15 cfs 100 Year Hydrology Calculations for Jerez Townhomes Area C Site Data Value Units Graded Area 5662.8 sf Soil Group C Pre Project Runnoff Coefficient "C" 0.30 Post Project Project Runnoff Coefficient "C" 0.69 Pre Proiect 100 vear 6hr Runoff Pre Project Ti 10.90 min Earth Swale Length 150.00 ft Earth Slope 0.02320 percent Earth Swale Z 20.00 Earth Swale N 0.025 Earth Swale Flow Depth 0.126 ft Earth Swale Velocity 0.40 ft/sec Earth Swale Tt 6.27 min Tc - Ti + Tt 17.17 min 100 year 6 hr Depth 2.75 in 100 year 6 hr intensity 3.27 in/hr 100 Year flow rate 0.13 cfs Post Proiect 100 year 6hr Runoff Post Project Ti 5.10 min Length 90.00 ft Slope 0.009 percent Swale Z 50.00 Swale N 0.02 Swale Flow Depth 0.155 ft Swale Velocity 0.62 ft/sec Swale Tt 2.44 min Tc 7.54 min 100 year 6 hr Depth 2.75 in Infiltration Depth (See Storm Water Calculations) 0.61 in Effective 100 6hr Depth 2.14 in 100 year 6 hr intensity 4.33 in/hr Graded Area 5662.80 ft'^2 100 Year flow rate 0.39 cfs 100 Year Hydrology Calculations for Jerez Townhomes Area D Site Data Value Units Graded Area 9147.6 sf Soil Group C Pre Project Runnoff Coefficient "C" 0.3 Post Project Project Runnoff Coefficient "C" 0.69 Pre Proiect 100 year 6hr Runoff Pre Project Ti 10.90 min Earth Swale Length 150.00 ft Earth Slope 0.02320 percent Earth Swale Z 20.00 Earth Swale N 0.025 Earth Swale Flow Depth 0.152 ft Earth Swale Velocity 0.45 ft/sec Earth Swale Tt 5.53 min Tc = Ti + Tt 16.43 min 100 year 6 hr Depth 2.75 in 100 year 6 hr intensity 3.36 in/hr 100 Year flow rate 0.21 cfs Post Proiect 100 vear 6hr Runoff Post Project Ti 5.10 min Length 164.00 ft Slope 0.009 percent Swale Z 50.00 Swale N 0.02 Swale Flow Depth 0.155 ft Swale Velocity 0.67 ft/sec Swale Tt 4.07 min Tc 9.17 min 100 year 6 hr Depth 2.75 in Infiltration Depth (See Storm Water Calculations) 0.61 in Effective 100 6hr Depth 2.14 in 100 year 6 hr intensity 3.81 in/hr Graded Area 9147.60 ft'^2 100 Year flow rate 0.55 cfs Hydraulic Evaluation Summary Subarea Preproject Post Project C 1 A Q C 1 A Q Difference (in/hr) (acres; (cfs) (in/hr) (acres) (cfs) (cfs) A 0.30 3.15 0.070 0.07 0.69 3.87 0.070 0.19 0.12 B 0.30 3.77 0.050 0.06 0.69 3.77 0.050 0.15 0.09 C 0.30 3.27 0.130 0.13 0.69 4.33 0.130 0.39 0.26 D 0.30 3.36 0.210 0.21 0.69 3.81 0.210 0.55 0.34 Total 0.46 1.27 0.81 SAN DIEGO HYDROLOGY MANUAL (ATTACHMENTS) Table 3.1 and Table 3.2 San Diego Coooty Hydrology Manual Daw: June 2003 Seclion: 3 6 of 26 Table 3-1 RUNOFF C OEFnCTEXTS FOR l'RB.4N AREAS Land Use Rnooflr CoefiBcieot "C" Soit Type NRCS Elwaenis Coiwty Eteiaeatt %MPER. c D 0.30 0.35 0.J6 041 0.42 0.46 0.45 049 0.4S 0.52 0.54 0.57 0.57 0.60 O.«0 06} 0.69 0.71 0.7S 0.79 0.78 0.7S» 0.81 082 084 085 0.S4 0.85 0.87 0.87 Undutufbed Nanuftl Tetram (Natural) Low Density Resicfentiat (LDR) Low Density Residential (LDR) Low Den.«ity Residential (LDR) Medium Density Residenitial (MOR) Medium Density RMidential (MDR) Medium Density Residential (MDR) Medium Density Residential (MDR) Hifb Dmuiy Residential (HDR) Htpx Deaeily Retidenlial (HDR) Comm«rcial:'Indt>stnal (N. Com) Commerciali Indtisirial (Q. Com) Conimertialilndustrial (O P. Com) Commerciali'Indttstriat (Limited I.) Commetcial'lndiMliial (General I.) Permanent Open Space Residentiat 1.0 DU A or less Residential 2.0 DU^A of less Residential 2 .9 DU'A or less Re^identiaL 4.3 DU A or less ResidentiiiL 7.3 OU A <a less ResideiUiaL 10.9 DU'A or Residential. 14 S DU'A or less Residetttial 24.0 DU'A or less ResideiuiaL 43.0 DU/A or less Neigbbortiood Cooinwrcial Ceoeral C^cnunercial Office ProfeiiioaalCooimercial Umiied Ittdosirial General Iiuiustrial 0» 10 20 25 50 40 45 50 65 80 SO 85 90 90 95 0.20 0.27 C Undeveloped j 038 04! 0.41 0.45 0.48 0.51 0.52 0.54 055 058 0.66 0.67 0.76 ("oj? C developed 080 0.80 0.S3 0S4 0.83 0.84 0.87 0.87 •The valves associated with 0*-» ti^perv'ious may be used for direct calculation ofthe ivnoff coefficient as described in Section 31 2 {lepresenliug the perviom mnoff coefficient. Cp. for the soil type), or for areas that will remain vndistHibed in perpetuity. Justification mustbe given tbat the arm will remain natural foie^er (e.g.. the area is localed in Cleveland National Foiest). DU'A - dwelling imits per acre NRCS National Rcsotirces Coi^rvation ServKC 3-6 Table 3-2 Undevetoped Ti MAXIMUM OVERLAND FLOW^NGTH (LM) & INITIAL TIME OF CONCEI Element* DU/ Acre .5% 1% 2% / 3% 5% 10% Element* DU/ Acre LM T. LM Ti LM V LM Tx LM Ti LM T. Natural 50 13.2 70 12.5 85 10.9 100 10.3 100 8.7 100 6.9 LDR 1 50 12.2 70 11.5 85 10.0 100 9.5 100 8.0 100 6.4 LDR 2 50 11.3 70 10.5 85 9.2 100 8.8 100 7.4 100 5.8 LDR 2.9 50 10.7 70 10.0 85 8.8 95 Q 1 1 r\T\ T r. 6 LDR 2.9 50 10.7 70 10.0 85 8.8 95 O.J Devetoped Ti 6 MDR 4.3 50 10.2 70 9.6 80 8.1 95 Devetoped Ti MDR 4.3 50 10.2 70 9.6 80 8.1 95 /7.8 100 b.l 100 5.3 MDR 7.3 50 9.2 65 8.4 80 7.4 T 7.0 100 6.0 100 4.8 MDR 10.9 50 8.7 65 7.9 80 6.9 /90 6.4 100 5.7 100 4 .5_ .3 MDR 14.5 50 8.2 65 7.4 80 6/ 90 6.0 100 5.4 100 4 .5_ .3 HDR 24 50 6.7 65 6.1 75 5L1 90 4.9 95 4.3 100 3.5 HDR 43 50 5.3 65 4.7 75 4.0 85 3.8 95 3.4 100 2 .7 .7 N. Com 50 5.3 60 4.5 75 4.0 85 3.8 95 3.4 100 2 .7 .7 G. Com 50 4.7 60 4.1 75 3.6 85 3.4 90 2.9 100 2.4 O.R/Com 50 4.2 60 3.7 70 31 80 2.9 90 2.6 100 2.2 LtDiitedL 50 4.2 60 3.7 70 3.1 80 2.9 90 2.6 100 2.2 General L 50 3.7 60 3.2 70 2.7 80 2.6 90 2.3 100 1.9 *See Table 3-1 for more detailed description INTENSITY-DURATION DESIGN CHART Figure 3-1 DiraelieM tor AppitoaMn: (1) From pradpitalkxi maps determine etv and 24 hratnounts for the sdected fiequency. Theae mam an included in IDs Counly Hyitology»tenial(10,50. and 100 yr maps induded In the Deaign and Preoedure Msnu^). (2) Adjust 6 Iv prec«iitation fif necessay) so that it is wittiin ttie range of 4S% lo 85% of the 24 hr precipitaliar (not acplicapletoOeMit). (3) Plot e hr precipitation on the right side of the chart. (4) OraHi 9 ine through the point parallel to the ptoOed lines. (5) Thia line is the inlen*lty.duistion cum for the location being anatyzed. (a) Selected fretiuency. . in.. P. 24-''24 (c) AdjuEled Pgl^l = _ (att^= min. (B) I = inJhr. I<tote: This ctian replaces the lntan£ity.OLirallan.Fra()usncy curves used since 1965. CURE Intaeuity^tantfoa Daaisn Cttatt - Tamptata County of SanDiego Hydrology Manual Rainfall Isopluvials 100 Year Rainfall Event - 6 Hours Isopluvial (Inches) r>pw/ ^GIS GIS IHIE l.*I.P IS PROWOEO WITHOUI WAHRAIJTY OF AHY KIND. OTHER EXPRECE OR WPLieo INCLl^OING. BUT NOT Llt/IIEO TO. ThE INtPUED WATtRANTlES oFMencMMtT^eliJTV *MD FiihJEss FOR APARHCULAR PURPOSE. Cepyisfhi SanGIS, AM Righis fieie-vnil. This pioducii may conUiln Inlonnalioa hom lh* SWDAO Regiooai ^ Nwmsiion Syslnm »*ich einnei bt inpioduced wiihoui the This p"K)uft m"* ron' qianied by Thomas BiDiheis Maps. jn whkh hit l>een wfxoduteri ivllli 3 0 3 Miles CALCULATIONS FOR 6" STORM DRAIN PIPE (Drains to Bioretention area witli vault) Input Parameters Diameter, Flow, Manning's coeff., Area, Hydraulic radius, D= Q= N= A= R= Z= Wetted perimeter, WP= 0.5 0.55 0.013 0.19635 0.125 1.486 1.5708 @Full capacity Friction slope. Sf = 0.009541625 HGL @ outlet Length of Pipe HGL @ inlet 40.05 53 40.56 Top of Grate elevation @ Inlet = 40.80 HGL @ inlet < Top of Grate elevation =>0K X ^ 9- £ I ONE Permeable Interlocking Concrete Pavement '/////////ffii} J; Storviwater Inlet Drain - hike Park, FL DF.VHl.OPMFN i; IMPERVIOUS COVER AND IMPAC rS OF S lORMWAI ER RUNOFF With ever-increa.sing levels of development, natural, open land is rapidly being replaced with imperviou.s surfaces such as asphalt roadways, parking lots, and buildings. As a result, the management of increased levels ot stormwater runoff and its impact on the environment has become a major issue for all levels of government throughout the country. Numerous studies indicate that stormwater runoff is the primary source of pollutants found in surface waters and contains a toxic combination of oils, pesticides, metals, nutrients, and sediments. Additionally, research has shown that once a watershed reaches just 10% iinpervious cover, water resources are negatively impacted. In the early 1990s, the United States Enviromnental Protec- tion Agency (EPA) established the National Pollutant Discharge Elimination System (NPDES) stormwater regulations to comply with the requirements ofthe Clean Water Act. Compliance with federal, state, and local stormwater programs involves the use of "best management practices" (BMPs) to manage and control stormwater runoff. Effective management of stormwater runoff offers a number of benefits, including improved quality of surface waters, protection of wedand and aquatic ecosystems, conservauon of water resources, and flood mitigation. I'he EPA recom- mends approaches that integrate control of stormwater and protection of natural systems. In 1999 and 2001, the International Ciry/County Managers Association (ICMA) and EPA released the frame- work for "Smart Growth" policies that communities around the country could adopt to meet environmental, communi- ty, and economic goals. Simultaneously, organizations such as the Low Impact Development Center and the Center for Watershed Protection began advocating low impact develop- ment (LID) as a way to preserve and protect the nation's water resources. They promote comprehensive land planning and engineering design, watershed planning and restoration, and stormwater management approaches that protect water resources and attempt to maintain pre-existing hydrologic site conditions. Their goal is ro achieve superior environ- mental protection, while still allowing for development. The EPA began working with these organizations in 2006 to promote the u.se of LID and Smart Growth as a way to manage stormwater runoff. The goal is to protect water resources at the regional level by encouraging states and municipalities to implement policies that consider both growth and conservation simultaneously. I hese approaches are quickly gaining favor across the country and are being incorporated into local development regulations to help meet stormwater runoff requirements and provide more livable, sustainable communities for residents. One of the I'riihitc RaidetUf - .\air,l'',nhctt, Rl primary goals of LID design is to reduce runoff volume by infiltrating rainwater on site and to find beneficial uses for the water as opposed to utilizing storm drains. LID objec- tives include the reduction of impervious cover, preservation of natural landscape features, and the maximization of in- filtration opportunities. Infiltration helps recharge ground- water, reduces urban heat island effects, and reduces down- stream erosion and flooding. This allows development to occur with much less environmental impact. In addition, "green building" programs are gaining in popularity. 'Lhe Leadership in Energ}' and Environmental Design (LEED*) green building assessment system, devel- oped by the U.S. Green Building Council, has been adopted by a number of cities and states that now require municipal buildings to meet LEED® certification standards. Also, the National Association of Home Builders (NAHB) has released a comprehensive guide on green building that promotes mixed-use developments, cluster housing, green technologies and materials, and alternative stormwater approaches. UNI HCO-SIONE ...THE SOLU FION lO SFO RVI WAFER RUNOFF PROBLEMS Permeable interlocking concrete pavements (PICPs) are becoming increasingly popular as more cities and states are faced with meeting stormwater runoff regulations, increased impervious cover restrictions, and the adoption of LID or LEED'" practices. UNI Fco-Stone'- Eco-Stone® is a permeable interlocking concrete pavement .system that mitigates stormwater runoff through infiltration. This allows for reduction of volume and peak flows, improved water qualit}', filtering of pollutants, miti- gation of downstream flooding, and recharge of ground- water. Eco-Stone® is a true interlocking paver that offers the structural support, durability, and beauty of traditional concrete pavers, combined with the environmental benefit of permeability. "Lhe permeability is achieved through the drainage openings created by its notched design. Measure- ments of a typical UNI Eco-Stone*' paver and physical characteristics are shown in Figure 1. Physical Characteristics Height/Thickness 31/8" Width 41/2" Length 9" Pavers per sq ft Percentage of drainage void area per sq ft Composition and IVIanufacture Minimum compressive strength - SOOOpsi Maximum water absorption - 5% Meets or exceeds ASTM C-936 and freeze-thaw testing per section 8 of ASTM C-67. = 80mm = 115mm = 230mm = 3.55 = 12.18% Figure I The drainage openings in an Eco-Stone* permeable pavement are created when the pavers are installed (Figure 2). This is what distinguishes Eco-Stone"" permeable pavers from traditional interlocking concrete pavers. Lhe drainage openings are filled with a clean, hard crushed aggregate that is highly permeable, allowing for rapid infiltration of stormwater (Figure 3). Figure .3 ECO-S i ONE PERMEABLE PAVEMEN F AS AN EPA BES'l MANACEMEN F PRACFK F 'Lhe EPA encourages "system building" to allow for the use of appropriate site-specific practices that will achieve the minimum measures under Phase II of NPDES. Governing authorities must develop and implement strategies that include a combination of structural and/or non-structural BMPs appropriate for their communities. Structural practices include storage practices, filtration practices, and infiltration practices tbat capture runoff and rely on infil- trafion through a porous medium for pollutant reduction. Infiltration BMPs include detention ponds, green roofs, bioswales, infiltration trenches, and permeable pavements. Non-structural practices are preventative actions that involve management and source controls. Many states and munici- palities have incorporated the EPA regulations into their stormwater design and BMP manuals as they attempt to deal with stormwater runoff, increased impervious cover, and over-taxed drainage and sewer systems. PICPs are considered structural BMPs under infiltration practices. From an engineering viewpoint, permeable pave- ments are infiltration trenches with paving on top that supports pedestrian and vehicular traffic. By combining infiltration and retention, Eco-Stone® permeable inter- locking concrete pavement offers numerous benefits over other types of structural .systems. Permeable pavements also work well in conjunction with other recommended BMP practices such as swales, bioretention areas, and rain gardens. Rainuhiter Rumlf Model - Minnehaha Creelt Watershed Distriet, MN ECO S IONE PERMEABEE PAVEMEN F AND FID, FEED AND (.REEN BUILDING According to the Natural Resources Defense Council, LID has emerged as an attractive approach to controlling stormwater pollution and protecting watersheds. With reduction of impervious surfaces a major tenant of LID, permeable and porous pavements, such as Eco-Stone®, are listed as one ofthe ten most common LID practices. 'Lhe use of site-scale technologies, such as PICPs that control runoff close to the source, closely mirror the natural process of rainwater falling onto undeveloped areas and infiltrating into the earth. With many areas ofthe country experiencing water shortages and increasing water pollution, LID and Smart Growth approaches will not only help alleviate these problems, but also create cities that are more energy efficient, environmentally sustainable, and cost effective. ,¥eKinnij Green Building, MeKinney, I'X - LEED'" Platinum Certified .Sherwood Island State Park - Westport. Cl Lhe LEED® green building assessment system has be- come increasingly popular with the North American design community since its inception in 1998. I his voluntary building system for rating new and existing commercial, institutional, and high-ri.se residential buildings, evaluates environmental performance from a "whole building" perspec- tive over the projects life cycle. New green design standards are being considered for neighborhood design and residential homes as well. 'Fhe minimum number of points or credits for a project to be LEED® certified is 26, though silver (3.3- 38 points), gold (39-51 points), and platinum (52-69 points) ratings also are available. UNI Eco-Stone* permeable pavements may qualify for up to 14 points under the Sustainable Sites (SS), Material and Resources (MR), and Innovation and Design Process (ID) credits. While traditional concrete pavers also may qualify under some of the credits, PICP can earn LEED* points via Sustainable Sites stormwater management credits by meeting water quality and runoff treatment criteria. For years, most home builders and developers were wary of green building practices. However, with impervious cover restrictions and the increasing costs of energy now beginning to impact residential projects, the NAHB is encouraging the u.se of "green" products in single and multi- family developments. Eco-Stone* permeable pavement offers an attractive solution to impervious cover restrictions. ECO-S I ONE AND MUNICIPAF S l ORM- WAI ER MANACEMENI OBJECIIVES Municipal regulations for managing stormwater runoff vary across the country. Water quality and/or quantity may be regulated, with criteria for reducing water pollutants such as nitrogen, phosphorous, nitrates, metals, and sediment. Many municipalities now restrict the amount of impervious surfaces for virtually all types of construction, including private residences. Lhousands of municipalities have created stormwater utilities to fund the increasing costs of managing stormwater. These fees vary, but are usually based on runoff volumes and impervious cover. Private Residenee - l ong Island, NY Lafayette Road (Jffiee Park - North Hampton, NPI Regional authorities, counties, and municipalities use a number of design goals for managing stormwater runoff: • Limit impervious cover to reduce stormwater runoff and pollutants from developments I C^apture the entire stormwater volume so there is zero discharge from the drainage area • Capture and treat stormwater runoff to remove a stated percentage of pollutants • Capture and treat a fixed volume of runoff typically 0.75-1.5 in. (18-40 mm), which usually contains the highest level of pollutants • Maintain runoff volumes generated by development at or near pre-development levels • Maintain groundwater recharge rates to sustain stream flows and ecosystems and recharge aquifers Eco-Stone® permeable interlocking concrete pavements may offer .solutions for attaining all of these goals. PICP can reduce runoff volumes and flows and recharge groundwater. It also can filter pollutants with removal rates ot up to 95% total suspended solids, 70% total phosphorous, 51 % total nitrogen, and 99% zinc. Reduction of runoff also may offer property owners reductions in stormwater utility fees. I EAI URFS AND BENEFI IS OF Fill UNI FCO-S FONE PAVEMEN I SYS FFM Eco-Stone'"' is an attractive pavement that can be used for residential, commercial, institutional, and recreational pedestrian and vehicular applications. It can be used for parking lots, driveways, overflow parking, emergency lanes, boat ramps, walkways, low-speed roadways, and storage facilities. Permeable or porous pavements should not he used for any site classified as a stormwater hotspot (anywhere there is a risk of stormwater contaminating groundwater). This includes fueling and maintenance stations, areas where hazardous materials or chemicals are stored, or land uses that drain pesticides/fertilizers onto permeable pavements. UNI Eco-Stone'"' permeable pavements are a site-scale infiltration technology that is ideal lor meeting the L.PA's NPDES regulations, LID and Smart Growth objectives, LEED'"' certification, municipal and regional impervious cover restrictions, and green building requirements. B Can be designed to accommodate a wide variety ot stormwater management objectives • Runoff reductions ol up to 100% depending on project design parameters B Maximizes groundwater recharge and/or storage I Reduces nonpoint source pollutants in stormwater, thereby mitigating impact on surrounding surface waters, and may lessen or eliminate downstream flooding and streambank erosion I Allows better land-use planning and more efficient use ot available land tor greater economic value, especially in high-density, urban areas • May decrease project costs by reducing or eliminat- ing drainage and retention/detention systems • May reduce cost ot compliance with stormwater regulatory requirements and lower utility fees •I May reduce heat island effect and thermal loading on surrounding surface waters (Hen Brook Creen. Jordan Cove Watershed - Waterford, CP Examples of pollutant removal and infiltration rates for Eco-Stone® are shown in 'Fables 1 and 2. 'Fhis data is trom the Jordan Cove Urban Watershed Project 2003 Annual Report by the University of Connecticut, who conducted monitoring on this EPA Section 319 National Monitoring Project. It should be noted that these infiltration results were achieved using a dense-graded base. Even higher infiltration rates would be expected with open-graded bases. Test and Year Asphalt Eco-Stone'^ In./hr (cm/hr) Crusheil Stone In./hr (cm/hr) Single Ring Infiltrometer test 2002 0 7.7 (19.6) 7.3 (18.5) Single Ring Infiltrometer test 2003 0 6 (15,3) 5(12.7) Flowing Infiltration test 2003 0 8.1 (20.7) 2.4 (6) Table 1. Avcra^^c infiltration rate.': (rom aspl.utlt, hco-Storu''- <i)i({ crusl)cd stone Jordan C.ovc Urban Watershed Project Variable Asphalt Eco-Stone Pavement Crusheil Stone Runoff depth, mm 1,8 a 0,5 b 0,04 c Total suspended solids, mg/1 47,8 a 15.8 b 33.7 a Nitrate nitrogen, mg/1 0,6 a 0.2 b 0.3 ab Ammonia nitrogen, mg/1 0.18 a 0.05 b 0,11 a Total Kjeldalil nitrogen, mg/1 8,0 a 0,7 b 1,6 ab Total phosphorous, mg/1 0.244 a 0,162 b 0.155 b Copper, ug/l 18 a 6 b 16 a Lead, ug/l 6 a 2 b 3 b Zinc, ug/l 87 a 25 b 57 ab Table 2. Mean weekly pollutant concentration in stornnvatcr riinolj from asphalt, hco-Stone"- and crushed stone drweways Note: Within each variable, rneans followed by the same letter are not significantly different at tl =0.0^ ECO S FONF DESIGN AND (,ENERAL ( ()NS FIU iC FION G U11)FEIN ES UNI-CROUP U.S.A. offers design professionals a variety ot tools for designing Eco-Stone'"' permeable pave- ments. Research on Eco-Stone® has been conducted at major universities such as lexas A&M, University ot Washington, and Guelph University, and ongoing pollution monitoring is being conducted at EPA Section 319 National Monitoring Program sites Jordan Cove Urban Watershed Project in C'onneclicut and Morton Arboretum in Illinois. We otter design manuals, case studies, and Lockpave"" Pro structural interlocking pavement design .software, with PC-SWMM PP '"' for hydraulic design of Eco-Stone'" permeable pave- ments. Eco-Stone® is featured in the book Porous Pavements by Bruce Ferguson, a national authority on stormwater infiltration. And, as members of the Interlocking Concrete Pavement Instittite, we can offer additional design and reference information, such as ICPLs Permeable Interlocking Concrete Pavements manual. Lech Specs'" and C^AD files. It is recommended that a qualified civil engineer with knowledge in hydrology and hydraulics be consulted tor applications using permeable interlocking concrete pavement lo ensure desired results. Information provided is intended for use by professional designers and is not a substitute tor engineering skill or judgement. It is not intended to replace the services ot experienced, protessional engineers. Design Option.s - Full, Partial and No Flxfiltration Eco-Stone® pavements can be designed with full, partial, or no exfiltration into the soil subgrade. Optimal installa- tion is infiltration through the base aggregate, with complete exfiltration into a permeable subgrade. 'Fhis allows for not only runoff and pollutant reduction, but also groundwater recharge. For full exfiltration under vehicular loads, the minimum soil infiltration rate is typically 0.52 in./hr (3.7 x 10 '' m/sec). Where soil conditions limit the amount ot infiltration and only partial exfiltration can be achieved, some ofthe water may need to be drained by perforated pipe. Where soils have extremely low or no permeability, or con- ditions such as high water tables, poor soil strength, or over aquifers where there isn't sufficient depth of the soil to filter pollutants, no exfiltration should occur. An impermeable liner is often used and perforated pipe is installed to drain all stored water to an outfall pipe. 'Fhis design still allows tor infiltration of stormwater and some filtering of pollutants and slows peak rates and volumes, so it still can be beneficLal for managing stormwater. For extreme rainfall events, any overflows can be controlled via perimeter drainage to bio- retention areas, gras.sed swales or storm sewer inlets. Ash Avenue Park and Ride - Marysville, U-yl Infihratioii Rate Design Permeable interlocking concrete pavements are typically designed to infiltrate frequent, short duration storms, which make up 75-85% of rainstorms in North America. It also may be possible to manage runoff volumes from larger storms through engineering design and the use of comple- mentary BMPs, such as bio-retention areas and swales. One ofthe most common misconceptions when design- ing or approving PICP is the assumption that the amount or percentage ot^ open surface area of the pavement is equal to the percentage of perviousness. For example, a designer or municipal agency might incorrectly assume that a 15% open area is only 15% pervious. The permeability and amount of infiltration are dependent on the infiltration rates of the aggregates used for the joint and drainage openings, the bedding layer, and the base and subbase (if used). Com- pared to soils, the materials used in Eco-Stone® permeable pavements have very high infiltration rates - from 500 in./hr (over 10 ' m/sec) to over 2000 in./hr (over 10 ' to 10 - m/sec). Fhis is much more pervious than existing site soils. Private Residence - Minneapolis. MN Lhough initial infiltration rates are very high, it is important to consider lifetime design infiltration of the entire pavement cross-.section, including the soil subgrade when designing PICPs. Based on research conducted to date, a conservative design rate of 3 in./hr (2.1 x 10"^ m/sec) can be used as the basis for the design surface infiltration rate over a 20-year pavement life. A number of design methods may be used fbr sizing of the open-graded ba.se (see references). For designers who use Natural Resources Conservation Service (NRCS) curve num- bers in determining runoff calculations, the curve number fbr PICP can be estimated at 40, assuming a life-time design infiltration rate of 3 in./hr (75mm/hr) with an initial .abstr.ac- tion of 0.2 (applies to NRCS group A soils). Other design professionals may use coefficient of runoff (C) for peak runoff calculations. For the design life of permeable inter- locking concrete pavement, C can be estimated with the following formula: C = I - Design infiltration rate, in./hr + I, where I = design rainfall intensity in inches per hour. (lonstiuction Materials and Genera! Installation It is preferable that site soils not be compacted if structural strength is suitable, as compaction reduces infiltra- tion rates. Low CBR soils (<4%) may require compaction and/or stabilization for vehicular traffic applications. E)rains also would Typically be required for low CBR soils. It soils must be compacted, the reduced infiltration rates should be factored into the design. Permeable and porous pavements should not exceed 5% slope for maximum infiltration. Goodhys Marina - Jaeksonville, PL Permeable interlocking concrete pavements are typically built over open-graded aggregate bases consisting of washed, hard, crushed stone, though a variet}' of aggregate materials, including dense-graded, may be used depending on project parameters. Typically, stone materials should have less than 1 % fines passing the No. 200 sieve. Current industry recommendations include a subbase of open-graded aggregate (typically ASTM No. 2 or equivalent) at a minimum thickness of 6 in. (150mm) for pedestrian applications and 8 in. (200mm) for vehicular applications. Lhis makes it easier for contractors to install the base materi- als. A base layer of open-graded aggregate (typically AS'LM No. 57 or equivalent) is installed over the subbase. Lhis helps meet filter criteria between the layers. 'Lhe recommend- ed thickness for this layer is 4 in. (100mm). It may be pos- sible, however, to use a single material for the base and subbase depending on project design parameters and con- tractor experience. Open-graded materials described here r}'pically have a water storage void space between the aggre- gates of between 30-40%, which maximizes storage ot in- filtrated stormwater. r/P NO S ACOR^GATr in OPCNItJGC ECO'SIONE PAVER roR t>/CRFiawO«Ai.*AC.i; .CURS &HO/VP;I BEDDING COURSE - I V'?TO;'t*0TOMMMirHICK iri'P UO eAGGfiEGATE;. - fl- SlOO MMf TMICrf ITVP NO 5' S^OME ' OPEN-GRAEJCD BASE yp NO 2 STONEI soil SueCPJvOE , ZERO iLOn Figure 4 - lypical Cross-Section of nn Eco-Stone'^' I\i-nieable Pavement Pull Exfiltration For the bedding layer, material equivalent to AS I'M No. 8 stone is recommended. Lhis same material is u.sed to fill the drainage openings and joints. If desired, material equivalent to No. 9, 10 or 89 stone also m.ay be used to fill the smaller joints between the pavers. Bedding and jointing sand used in the construction of traditional interlocking concrete pavements should not be used for PICP. Private Residence - Danvers, MA Ihe liullege .School ofWebster Groves - St. Louis, MO UNI Eco-Stone® can be mechanically installed and trafficked immediately after final compaction, unlike other types of porous pavements. It has been used successfully for many years throughout North America and can withstand repeated freeze/thaw in northern climates due to adecjuate space for ice to expand within the open-graded ba.se. PICP can be snow plowed, and because water does not stand on the surface, it may reduce ice slipping hazards. Winter sanding is' not recommended on PICPs. Permeable inter- locking concrete pavement conforms to current ADA requirements that surfaces be firm, stable, and slip resistant. If the openings in the surface are not desirable, solid pavers can be installed in areas used by disabled persons. .Maintenance All permeable pavements require periodic cleaning to maintain infiltration, and care must be taken to keep sedi- ment off the pavement during and after construction. Studies and field experience have shown that vacuum-type street cleaning equipment is most effective for removing sediment from the openings to regenerate infiltration. Vacuum settings may require adjustment to prevent the uptake of aggregate in the pavement openings and joints. Lhe surface should be dry when cleaning. Replenishment ot joint and opening aggregate can be done, if needed, at the time of cleaning. Lhe frequency of cleaning is dependent on traffic levels. It is generally recommended to vacuum the pavement surface at least once or twice a year, though some low-use pavements may not need cleaning as often. As street cleaning is a BMP under EPA guidelines, this also sadsfies other criteria in a comprehensive stormwater management program. If properly constructed and maintained, PICP should provide a service life of 20 to 25 years. Like our traditional interlocking concrete pavers, Eco-Stone® may be taken up and reinstated if underground repairs are needed. If at the end of its design life the pavement no longer infiltrates the required amount of stormwater runoff, PICP is the only type of permeable pavement that can be taken up, the base materials removed and replaced, and the pavers reinstalled. UNI ECOEOC HEAVY-DU FY PERMEABFF FN l EREOCKlNG CONCRE I E PAVEMEN F Ecoloc* features all the same attributes and features of our Eco-Stone"'-" permeable paver with the added benefit of supporting industrial loads. It can be used together with our industrial traditional interlocking paver, UNI- Anchorlock® to provide design professionals with the option of combining solid pavement areas with permeable areas. Pcoloe''" luith UNi-Anchorlock^' Like Eco-Stone*, Ecoloc® features funnel-shaped openings that facilitate the infiltration of stormwater r Physical characteristics are described in Figure 5. Physical Characteristics Height/Thickness 3 1/8" = 80mm Width 8 7/8" = 225mm Length 8 7/8" = 225mm Pavers per sq ft = 2.41 Percentage of drainage void area per sq ft = 12.18% Composition and Manufacture Minimum compressive strength - 8000psi Maximum water absorption - 5% Meets or exceeds ASTM C-936 and freeze-thaw testing per section 8 of ASTM C-67. Figure 5 Ecoloc* can be mechanically installed and is ideal for larger-scale projects such as parking lots, roadways, storage and depot areas, and ports. Over 173,000 sf of Ecoloc® was used for an EPA Section 319 National Monitoring Permit -S- ^i^S^tm^'-ir-'. • Project at Morton Arboretum in Illinois. It also is in use at a test site located at Howland Hook Terminal at the Port of New York/New Jersey that is subjected to heavy, containerized loads, port forklifts and cargo carriers. Another 30,000 sf of Ecoloc "' was installed at the E.ast Gwillimbury Go Commuter 'Frain Station parking lot in Newmarket, Ontario. Seneca Colleo;e - Poronto, Ontario Morton Arboretum - DuPage County, II. In addition, Ecoloc® is undergoing an evaluation at Seneca College in Ontario for the loronto and Region Conservation Authority to study permeable interlocking concrete pavement performance in cold climates conditions. Please check with your local UNI® manufacturer tor availability of Ecoloc® in your area. Please visit our website www.uni-groupusa.org for updated information, design references and research, a list of manufacturers, and more. East {iivilhtuhury Go Commuter Prain Station - Newmarket, Ontario REFERENCES & RESOURCES "Animal Report - Jordan Cove Urban Watershed Section 319 National Monitoring Program L^roject. University oi C^onneclicat, 200.5 " l/Nl Eco-Stone^' Design Guide and Research .Summary ' Lockpave " Pro structural design sojiware with PC-SWMAP'' PP hydraulic design software 'Porous Pavements - Bruce K. Fergu.soji, (^RC Pres.s, 2005 ' Permeable Interlockhig Concrete Pavements - Inceriocking C^oncretc I'avcmcn! In.si itute. 2006 A special thank you to the Interlocking Concrete Pavement Institute for use of sonic project photos. Pront cover photos: Eco-Stone' - Private Residenee Cape Cod. AIA and Ecoloc '''' - Westmoreland .Street Project - Portland, OR UNI La)-Scnnc" and UNI Fcciloc" are registered trademarks ot F. von Faiigsdortt Lie, Ftd., C aledon, (.)ntario. Canada 4)2(1116-2007 liXI-(.;Rl)l,"l> i:.S„\, I'nrufd in th:- l.:.S.,\, UNI-GROUP U.S.A. - National Headquarters Office 4362 Noiihlakc Blvd, • Suite 204 • Palin Beach (iaixleiLs, Fi, .5.5410 (561) 626.-4666 • FAX (56i) 627-6403 • 1-800-872-1864 wwvv.utii-groupu.sa.org • E-mail: irifoC'^^utit-groupusa.org APPENDIX F Calculations IVCJJUl I IVCSUIl Project Name JEREZ CT Project Applicant TMS DEVELOPH/IENT LLC Jurisdiction City of Carlsbad Parcel (APN) 216-290-09 Hydrologic Unit Carisbad Compliance Basin Summary Basin Name: BASIN 1-OVERALL Receiving Water: JEREZ CT Rainfall Basin Oceanside H/tean Annual Precipitation (Inches) 13.3 Project Basin Area (acres); 0.41 Watershed Area (acres): 0.00 SCCWRP Lateral Channel Susceptlbiity (H, Nl, L): SCCWRP Vertlflcal Channel Susceptlbiity (H, M, L): Overall Channel Susceptibility (H, M, L): HIGH Lower Flow Threshold (% of 2-Year Fiow): 0.1 I Summary ID Area (ac) Pre-Project Cover Post Surface Type Drainage Soli Slope 25624 Drains to LID BIWP1 LANDSCAPE 0.01 Pen/ious (Pre) Landscaping 25625 Drains to LID BMP1 PATIOS 0.02 Pervious (Pre) Concrete or asphalt Type C (slow infiltration) Flat-slope (less... 25626 Drains to LID BMP 1 ROOFS 0.02 Pervious (Pre) Roofs Type C (slow infiltration) Flat-slope (less... Concrete or asphalt Type C (slow infiltration) Flat - slope (less ... 25627 Drains to LID BMP 1 DRIVEWAYS, SIDEWALKS, ETC 0.00 Pervious (Pre) Concrete or asphalt Type C (slow infiltration) Flat - slope (less ... 25628 Drains to LID BMP 2 LANDSCAPE 0.00 Pervious (Pre) Concrete or asphalt Type C (slow infiltration) Flat-slope (less... 25629 Drains to LID BMP 2 PATIOS 0,01 Pen/ious (Pre) Concrete or asphalt Type C (slow infiltration) Flat - slope (less ... i i 25630 Drains to LID BMP 2 ROOFS 0,03 Pervious (Pre) Roofs Type C (slow infiltration) Flat - slope (less ... 1 25631 1 25632 i Drains to LID Drains to LID BMP 3 BMP 3 LANDSCAPE ROOFS 0,00 0,01 Pervious (Pre) Pervious (Pre) Landscaping Roofs Type C (slow infiltration) Type C (slow infiltration) Fiat-slope (less ... Flat-slope (less... http://uknow.brwiicald.com/wastewater/Toolkits/Watershed/SiteToolkit/ReportResult.^ 4/9/2013 ivepuii ivcsuii 1 25633 Drains to LID BMPS DRIVEWAYS, SIDEWALK. ETC 0.02 Pervious (Pre) Pervious concrete or asphalt Type C (slow infiltration) Flat-slope (less... 25634 Drains to LID BMP 4 LANDSCAPE 0.00 Pervious (Pre) Landscaping Type C (slow infiltration) Flat-slope (less, ,, 25635 Drains tc LID BMP 4 ROOFS 0.01 Pervious (Pre) Roofs Type C (siow infiltration) Flat-slope (less,,, 25636 Drains to LID BMPS LANDSCAPE 0,03 Pervious (Pre) Landscaping Type C (slow infiltration) Flat-slope (less „. 25637 Drains to LID BMPS PATIOS 0.01 Pervious (Pre) Concrete or asphalt Type C (slow infiltration) Flat-slope (less,,, 25638 Drains to LID BMPS ROOFS 0,06 Pervious (Pre) Roofs Type C (slow infiltration) Flat-slope (less... 25639 Drains to LID BMPS DRIVEWAYS, SIDEWALK. ETC 0.11 Pervious (Pre) Pervious concrete or asphalt Type C (slow infiltration) Flat-slope (less, ,, BMP ID Type Description Pian Area (sqft) Volume 1(cft) Volume 2(cft) Orifice Flow/ (cfs) Orifice Size (inch) BMP 1 Flow-Through Planter FLOW THROUGH PLANTER 441 367 264 0.001 0,1 BMP 2 Flow-Through Planter FLOW THROUGH PLANTER 413 344 248 0.000 0.1 BMP 3 Flow-Through Planter FLOW THROUGH PLANTER 110 91 66 0.000 0.1 BMP 4 Flow-Through Planter FLOW THROUGH PLANTER 152 126 91 0.000 0.0 BMPS Bioretention + Vault BIORETENTION 157 1022 0.00 0.003 0.2 httD://uknow.brwncald.com/wastewater/Toolkits/Watershed/SiteToolkit/ReportResult.aspx?pid=138617&bid 4/9/2013