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Home My WebLink AboutCT 13-03; ROBERTSON RANCH WEST VILLAGE; SWMP; SDP 15-01, DWG 480-3B; 2015-09-11I I I I I I I I I I I C C I I I I I C I CITY OF CARLSBAD I PRIORITY DEVELOPMENT PROJECT STORM WATER MANAGEMENT PLAN SWMP# 15-15 FOR ROBERTSON RANCH RECREATION CENTER SDP 15-01 I CT 13-03 I DWG 480-36 ENGINEER OF WORK /y--J) ~ DAVID WIENER-RCE #77285-EXP. 06/30/17 PREPARED FOR: Toll Brothers 725 West Town and Country Road, ruife 200 . . 1 Orange,CA92868 ;1 R~F~CF,Al\71~[) . Contact: Greg Deacon ij SEP 2 5 2015 Phone: C959l 558-3650 !LAND Of.vELOPfviENT 1 EN·G11..~1=~RIN '"' 1 I\ r . . JV~~ ~--· -~/ J PREPARED BY: Michael Baker International 5050 Avenida Encinas, Suite 260 Carlsbad, CA 92008 Contact: David Wiener (760) 603-6252 Submitted: July 23, 2015 Revised: September 11, 2015 I I I I I I I I I I I I I I I I TABLE OF CONTENTS 1.0 Declaration of Responsible Charge .................................................................................... 3 2 .0 Summary of Project Information ........................................................................................ 4 3.0 Pre-Project Site Conditions and Drainage Patterns Narrative ................................. 5 3.1 Site Development Constraints 4.0 Proposed Site Development and Drainage Patterns Narrative ................................ 6 4.1 Site Development Opportunities 5.0 Sources of Pollutants from the Existing Site Narrative ............................................... 7 6.0 Project Hydrologic Location ................................................................................................. 8 7 .0 Identification of 303( d) Impaired Receiving Waters ................................................... 9 8.0 Identification of Pollutants Associated with Priority Project Category .............. 10 9.0 Identification of Pollutants of Concern ........................................................................... 12 10.0 Uydromodification Management Plan (UMP) Applicability Determination ..... 13 10.1 Summary of UMP Compliance Approach 11.0 Permanent Source Control Best Management Practices (BMPs) .......................... 17 12.0 Identification of BMPs Applicable to Individual Priority Project Categories .... 21 13.0 Implementation of Site Design Low Impact Development (LID) Practices ........ 26 14.0 Tabulation of Drainage Management Areas (DMAs) ................................................. 28 15.0 Relative Effectiveness of Project Treatment Facilities and IMPs .......................... 29 16.0 Projected Storm Water BMP Maintenance Mechanism ............................................ 30 17 .0 Summary and Conclusion Narrative ................................................................................ 31 Robertson Ranch Recreation Center Priority Development Project -Storm Water Management Plan Page i Michael Baker INTERNATIONAL I I I I I I I I I I I E I I I I m 18.0 Figures Vicinity Map NRCS Soil Survey Federal Emergency Management Agency (FEMA) Map BMPMap 19.0 Attachments Storm Water Standards Questionnaire Hydromodification Calculations BMP Fact Sheets Robertson Ranch Recreation Center Priority Development Project -Storm Water Management Plan Page ii Michael Baker INTERNATIONAL I I I I I I I I! I I I I 1.0 Declaration of Responsible Charge I hereby declare that I am the Engineer of Work for this project and that I have exercised responsible charge over the design of the project as defined in Section 6703 of the California Business and Professions Code, and that the design is consistent with current standards. I understand and acknowledge that the check of this Priority Development Project -Storm Water Management Plan by the City of Carlsbad is confined to a review and does not relieve me, as Engineer of Work, of my responsibilities for project design. As Engineer of Work, I agree to indemnify, defend, and hold harmless the City of Carlsbad, its officers, agents, and employees from any and all liability, claims, damages, or injuries to any person or property which might arise from the negligent acts, errors, or omissions of the Engineer of Work, my employees, agents or consultants. Robertson Ranch Recreation Center 9/11/2015 David Wiener RCE #77285 Date Michael Baker International Robertson Ranch Recreation Center Priority Development Project -Storm Water Management Plan Page3 Michael Baker INTERNATIONAL 2.0 Summary of Project Information Item Project Information Project Name Robertson Ranch Recreation Center Application Number(s) CT 13-03 Project Address Robertson Road and Wellspring Street Assessor Parcel Number(s) 208-010-44 Gross Project Area 1.20 Acres Net Project Area 1.20 Acres Proposed Project Description and Recreation: Pool, Spa, and clubhouse Land Use D Housing Development of 10 or more dwelling units D Commercial Development of one acre and greater 0 Heavy Industry of one acre and greater D Automotive Repair Shop D Restaurant Applicable Priority Development D Hillside Development greater than 5,000 square feet Project Categories D Water Quality Environmentally Sensitive Area (WQESA) ~ Parking Lot D Street, Highways, and Freeways D Retail Gasoline Outlets D Coastal Development Zone ~ Land Disturbance greater than one acre Project Disturbed Area 1.07 Acres 46,623 SF Predevelopment Impervious Area 0 Acres 0 SF Proposed Impervious Area 0.36 Acres 15,578 SF Proposed Pervious Area 0.71 Acres (includes 0.22 ac 31,045 SF pervious paving) Project Hydrologic Unit Watershed 904.31 -Carlsbad HU, Agua Hedionda HA, Los Monos HSA Project Hydrologic Soil Group DA IDs De ,~D Number of Discharge Locations 1 Location Required to Implement HMP ~Yes 0No Number of HMP Compliance Points 1 Location I Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan Page 4 INTERNATIONAL 3.0 Pre-Project Site Conditions and Drainage Patterns Narrative The pre-project condition refers to the land use prior to rough grading and improvements performed as part of the Robertson Ranch Development. The pre-project site condition is undeveloped with grassy cover and drains to the southeast at an average slope of 10%. There is no storm drain infrastructure in place. The runoff from the site flows south to El Camino Real, where it enters the public storm drain system. The storm drain continues west, and eventually outfalls to Agua Hedionda. 3.1 Site Development Constraints Applicable Site Development Constraints D Limited Available Hydraulic Head ~ Impermeable Soils D High Groundwater D Contaminated Soils D Geotechnical Instability ~ Perimeter Conditions D High Intensity Land Use D Heavy Pedestrian Traffic D Heavy Vehicular Traffic D Restricted Right-of-Way D Existing Easements D Inadequate Down-Stream Drainage Infrastructure D Public Safety Concerns D Other Comments: The project site contains Type D soils, making infiltration infeasible. Landscape slopes (2: 1 grade) exist on the west and south sides of the site. Robertson Ranch Recreation Center Priority Development Project -Storm Water Management Plan Page 5 Michael Baker INTERNATIONAL 4.0 Proposed Site Development and Drainage Patterns Narrative As part of the Robertson Ranch master development, the Recreation Center site will be rough graded at a 1 % slope to the southeast per City of Carlsbad Drawing Number 480-3A. The project site will be located northeast of the future intersection of Robertson Road and Welspring Street, with driveway access off of Robertson Road. The public improvements associated with these roadways will be constructed per City of Carlsbad Drawing Number 480-3. A 36" RCP storm drain is being constructed as part of these improvements in Robertson Road. The Recreation Center site is on Lot 341 of Carlsbad Tract No. 13-03-2. The lot is 1.20 gross acres with a 10-foot public drainage easement along its Robertson Road frontage. As mentioned above, the rough grading and frontage improvements will be completed prior to Recreation Center construction permit issuance. The Recreation Center site will consist of a pervious paver parking lot, swimming pool & spa, pool deck with cabanas, clubhouse, walkways, and landscaping. The site is divided into four Drainage Management Areas (DMAs). OMA A contains the clubhouse, hardscape and landscape which drain onto the pervious paver parking lot. The parking lot then drains to bioretention area (IMP-1) for water quality and hydromodification compliance. OMA B consists of the pool deck area, which directs flow to a trench drain that outlets to bioretention area (IMP-2) to the south. OMA C consists of the pool deck area, which directs flow to a trench drain that outlets to bioretention area (IMP-3) to the east. OMA D is a self-treating landscaped area within the public drainage easement to the south of the site. Proposed surface types and drainage areas can be found on the BMP Map. Robertson Ranch Recreation Center Priority Development Project -Storm Water Management Plan Page 6 Michael Baker INTERNATIONAL 4.1 Site Development Opportunities Applicable Site Development Opportunities [gl Adequate Available Hydraulic Head D Permeable Soils D Groundwater Separation D Geotechnical Stability D Perimeter Conditions D Existing Natural Areas D Undevelopable Areas [gl Adequate Down Stream Drainage Infrastructure D Other Comments: The site will connect to 36" storm drain pipe in Robertson Road. 5.0 Sources of Pollutants from the Existing Site Narrative There are no known sources of pollutants on the existing site. Robertson Ranch Recreation Center Priority Development Project -Storm Water Management Plan Page 7 Michael Baker INTERNATIONAL 6.0 Project Hydrologic Location Hydrologic Unit Hydrologic Area D Santa Margarita 902.00 D Ysidora 902.10 D San Luis Rey 903.00 D Lower San Luis 903.10 D Loma Alta 904.10 ~ Carlsbad 904.00 D Buena Vista Creek 904.20 ~ Agua Hedionda 4.30 Robertson Ranch Recreation Center Priority Development Project -Storm Water Management Plan Page 8 Hydrologic Sub-Area D LowerYsidora 902.11 D Mission 903.11 D Bonsall 903.12 Not Applicable D El Saito 904.21 D Vista 904.22 ~ Los Monos 904.31 Michael Baker INTERNATIONAL 7.0 Identification of 303(d) Impaired Receiving Waters Pollutant(s) Causing Receiving Water Impairment to 303(d) Receiving Water Enterococcus Fecal Coliform Manganese Phosphorus IZJ Agua Hed10nda Creek 90431000 (7 Miles) Selenium Sulfates Total Dissolved Solids Total Nitrogen as N Toxicity D Buena Vista Creek 90421000 (11 Miles) Sediment Toxicity Selenium Indicator Bacteria D Buena Vista Lagoon 90421000 (202 Acres) Nutrients Sediment/Siltation D Guajome Lake 90311000 (33 Acres) Eu trophic D Loma Alta Creek 90410000 (7.8 Miles) Selenium Toxicity D Loma Alta Slough 90410000 (8.2 Acres) Eutrophic Indicator Bacteria D Oceanside Harbor 90421000 (52 Acres) Copper D Pacific Ocean Shoreline, Loma Alta HSA, at Loma Alta Creek Mouth Indicator Bacteria 90410000 (0.03 Miles) D Pacific Ocean Shoreline, San Luis Rey HU, at San Luis Rey River Enterococcus Mouth 90311000 ( 0.03 Miles) Total Coliform Chloride Enterococcus San Luis Rey River & Lower Stream (West of Interstate 15) 90311000 Fecal Coliform D Phosphorus (19Miles) Total Dissolved Solids Total Nitrogen as N Toxicity D Santa Margarita Lagoon 90211000 (28 Acres) Eutrophic Enterococcus D Santa Margarita River (Lower) 90211000 (19 Miles) Fecal Coliform Phosphorus Total Nitrogen as N Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan Page 9 INTERNATIONAL 8.0 Identification of Pollutants Associated with Priority Project Category Priority Project Category General Pollutant Categories Sediment Nutrients Detached Residential Trash & Debris D Oxygen Demanding Substances Development Oil & Grease Bacteria & Viruses Pesticides Sediment Nutrients Attached Residential Trash & Debris D Oxygen Demanding Substances (if landscape exists on-site) Development Oil & Grease (if uncovered parking areas exist on-site) Bacteria & Viruses Pesticides Sediment (if landscape exists on-site) Nutrients (iflandscape exists on-site) Heavy Metals Organic Compounds (if uncovered parking areas exist on-site) Trash & Debris ~ Commercial Development Oxygen Demanding Substances (includes solvents) Oil & Grease Bacteria & Viruses (ifland use includes food or animal waste products) Pesticides (includes solvents) Sediment Heavy Metals D Heavy Industry or Organic Compounds Industrial Development Trash & Debris Oxygen Demanding Substances Oil & Grease Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan Page 10 INTERNATIONAL 8.0 Identification of Pollutants Associated with Priority Project Category ( continued) Priority Project Categories General Pollutant Categories Heavy Metals Organic Compounds (includes petroleum hydrocarbons and D Automotive Repair Shop solvents) Trash & Debris Oil & Grease Trash & Debris Oxygen Demanding Substances D Restaurants Oil & Grease Bacteria & Viruses Pesticides (if landscape exists on-site) Sediments Nutrients D Hillside Development Trash & Debris Oxygen Demanding Substances Oil & Grease Pesticides Sediments (iflandscape exists on-site) Nutrients (if landscape exists on-site) Heavy Metals [8J Parking Lots Trash & Debris Oxygen Demanding Substances (if landscape exists on-site) Oil & Grease Pesticides (if landscape exists on-site) Heavy Metals Organic Compounds D Retail Gasoline Outlets Trash & Debris Oxygen Demanding Substances Oil & Grease Sediments Nutrients (if landscape exists on-site) Heavy Metals Organic Compounds (including petroleum hydrocarbons) D Streets, Highways & Freeways Trash & Debris Oxygen Demanding Substances (includes solvents) Oil & Grease Bacteria & Viruses Pesticides (if landscape exists on-site) Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan Page 11 INTERNATIONAL 9.0 Identification of Pollutants of Concern Pollutants Associated Pollutants Causing Impairment to 303( d) with Priority Project Cate2orv Receiving Water(s) D Chloride D Sediment/Siltation D Copper D Sediment Toxicity [ZI Sediment D Nutrients [ZI Selenium [ZI Phosphorus [ZI Sulfates D Sediment [ZI Total Nitrogen as N D Chloride [ZI Sulfates [ZI Total Dissolved [ZI Nutrients D Eutrophic Solids D Nutrients [ZI Total Nitrogen as N [ZI Phosphorus [ZI Toxicity D Copper [ZI Sulfates [ZI Heavy Metals [ZI Manganese [ZI Total Dissolved Solids D Sediment Toxicity [ZI Toxicity [ZI Organic Compounds D Eutrophic [ZI Toxicity D Sediment Toxicity D Eutrophic [ZI Total Dissolved [ZI Trash & Debris D Nutrients Solids D Sediment Toxicity [ZI Toxicity D Eutrophic [ZI Sulfates [ZI Oxygen Demanding D Nutrients [ZI Total Dissolved Substances [ZI Phosphorus Solids [ZI Total Nitrogen as N [ZI Oil & Grease D Eutrophic [ZI Toxicity D Sediment Toxicity [ZI Enterococcus D Indicator Bacteria D Bacteria & Viruses D Eutrophic D Total Coliform [ZI Fecal Coliform D Copper D Sediment Toxicity [ZI Pesticides D Eutrophic [ZI Sulfates D Phosphate [ZI Toxicity [ZI Total Nitrogen as N Robertson Ranch Recreation Center Priority Development Project -Storm Water Management Plan Page 12 Pollutants of Concern [ZI Sediment [ZI Nutrients [ZI Heavy Metals [ZI Organic Compounds [ZI Trash & Debris [ZI Oxygen Demanding Substances [ZI Oil & Grease D Bacteria & Viruses [ZI Pesticides Michael Baker INTERNATIONAL 10.0 Hydromodification Management Plan (HMP) Applicability Determination NO End of Decision Matrix Robertson Ranch Recreation Center YES 11. Determine Domain of Analysis See HMP Section 5.2 Priority Development Project -Storm Water Management Plan Page 13 NO Redesign Energy Dissipation System 14. Hydrornodification Controls Required Go to Figure 6-2 of Decision Matrix Michael Baker INTERNATIONAL 10.0 HMP Applicability Determination (continued) HMP Applicability Determination Summary Node Component Response Response 1 Priority Development Project [8'.I Yes -Go to Node 2 D No-Exempt 2 Proper Energy Dissipation D Yes -Go to Node 3 Intentionally left blank Go to Node 3 3 Increase Impervious Area [8'.I Yes -Go to Node 4 D No -Go to Node 5 4 Increase Unmitigated Peak [8'.I Yes -Go to Node 5 D No-Exempt Flows to Any Outlet Location 5 Direct Discharge to an D Yes -Exempt [8'.I No -Go to Node 6 Exempt System 6 Direct Discharge to a Tidally D Yes -Potentially [8'.I No -Go to Node 7 Influenced Lagoon Area Exempt Direct Discharge to Stabilized 7 Conveyance to Exempt D Yes -Go to Node 8 [8'.I No -Go to Node 9 System Does Stabilized Conveyance 8 Have Capacity to Convey D Yes -Exempt D No -Go to Node 9 Ultimate QlO 9 Discharge to Highly D Yes -Exempt [8'.I No -Go to Node 10 Urbanized Area Urban Infill Project [8'.I No -HMP Controls Required 10 Discharging to Stabilized D Yes -Go to Node 11 Go to Node 14 Conveyance 11 Determine Domain of D Yes -Go to Node 12 Intentionally Left Blank Analysis Does Not Apply to Node 11 Stabilized Conveyance Extends Beyond Domain of [8'.I No -HMP Controls Required 12 Analysis and Eventually D Yes -Go to Node 13 Discharges to LOW Go to Node 14 Susceptibility Stream Cumulative Future Impacts cgj No -HMP Controls Required 13 Represent <3% Impervious D Yes -Exempt Go to Node 14 Area Increase 14 Go to HMP Figure 6-2 Mitigation Criteria and Implementation Comments: For the Recreation Center project, HMP Controls are required. Robertson Ranch Recreation Center Priority Development Project -Storm Water Management Plan Page 14 Michael Baker INTERNATIONAL 10.1 Summary of HMP Compliance Approach Summary of Project HMP Compliance Approach Software Selection D Not Applicable -Project Exempt from HMP requirements D Determine/Identify Point(s) of Compliance D Utilize SCCWRP Screening Tools to determine Stream Susceptibility D Default to a High Susceptibility Stream (0.1Q2) D Utilize an appropriate HMP Sizing Tool to demonstrate HMP compliance D Utilize HMP Sizing Tables to demonstrate HMP compliance ~ Utilize an approved Continuous Simulation Model and compare pre-project and mitigated post-project flows to demonstrate HMP compliance D HEC-HMS 0HSPF ~SOHM OswMM D Provide comprehensive, digital support data, calculation method and parameters, and calculation results on Compact Disk (CD) sufficient to duplicate study and support a RWQCB audit To provide a design that fully mitigates potential Hydromodification impacts, long-term continuous simulation hydrologic calculations were performed using the San Diego Hydrology Model (SDHM) and the Hydrologic Simulation Program Fortran (HSPF). HSPF has been the state-of-the-art program for long-term continuous simulation calculations since its initial development over 30 years ago. SDHM was used to facilitate the development of input files for HSPF. HSPF uses hourly rainfall data to develop long-term hydrology for the flow duration analysis. None of the City of Carlsbad approved precipitation gauges are in the immediate vicinity of the project site. The closest gauge geographically and in terms of average annual precipitation is the Oceanside precipitation gage, which is located approximately 6 miles north of the project site. Robertson Ranch Recreation Center Priority Development Project -Storm Water Management Plan Page 15 Michael Baker INTERNATIONAL Modeling Inputs Long-term continuous simulation hydrologic modeling requires that the drainage area within the project site be delineated in a manner consistent with the project-specific drainage study (under separate cover). Within the drainage basin, unique combinations of hydrologic soil type and land use are also delineated. The existing hydrologic soil type classifications are considered to be Type D based on NRCS Soils Map in Section 22. The proposed hydrologic soil type is considered to be Type D. The project proposes one point of connection (POC). This will occur where the proposed bioretention areas connect to the existing storm drain in Robertson Road. Existing ground cover was established based upon aerial imagery and aerial survey performed in 2010. The existing ground surface was modeled as steeply sloping (10-20%) grass for the entire site. Proposed ground cover was established based on the proposed site plan. The site will contain impervious hardscape & roofs, pervious paver parking lot, concrete pool deck, landscaping, and bioretention areas. The BMP Map presents the post-project land characteristics. Results Hydromodification impacts from development are mitigated using pervious pavement and bioretention areas. Complete results of the HSPF analysis are included in Hydromodification Calculations attachment. Typical details for bioretention areas and outlet structures, as modeled in SDHM, are shown on theBMPMap. The table below presents a summary of the partial duration peak runoff rates for the pre- development and post-development conditions. All of the peak flow rates have been mitigated to equal or less than the pre-development peak runoff rates. Summary of Partial-Duration Peak Flow Rates 2-Year 5-Year Pre-Mitigated i Pre-Mitigated POC Post-Post-Project Project Project Project (cfs) (cfs) (cfs) (cfs) 0.27 0.02 0.52 0.05 Robertson Ranch Recreation Center Priority Development Project -Storm Water Management Plan Page 16 IO-Year 25-Year Pre-Mitigated Pre-Mitigated Post-Post-Project Project Project Project (cfs) (cfs) (cfs) (cfs) 0.69 0.07 0.75 0.15 Michael Baker INTERNATIONAL Conclusions The results presented above show that mitigation of both peak flow and flow duration are accomplished for POC over the statistical range of events between I 0% of Q2 and QI 0 (hydromodification zone). The project, therefore, complies with the standards of the effective City of Carlsbad Standard Urban Stormwater Management Plan (SUSMP), dated January 2011. 11.0 Permanent Source Control Best Management Practices (BMPs) Source Control BMP Applicable Implementation Requirements ~ Provide prohibitive dumping placards and Lor signage ~ Post signage at public access points to deter prohibitive ~ Storm Drain Inlet Labeling dumping ~ Maintain legibility of placards and signage D Not Applicable Comment: D Materials placed in an enclosure ( e.g. cabinet, shed, or similar structure that prevents contact with rain, runoff or spillage to the storm water conveyance system) D Protected by secondary containment structures ( e.g. berms, dikes, or curbs) and paved or sufficiently D Outdoor Material Storage Areas impervious to contain leaks and spills D The storage area is paved and sufficiently impervious to contain leaks and spills D Includes a roof or awning to minimize direct precipitation to the secondary containment area ~ Not Applicable Comment: No proposed outdoor material storage areas. Robertson Ranch Recreation Center Priority Development Project -Storm Water Management Plan Page 17 Michael Baker INTERNATIONAL 11.0 Permanent Source Control BMPs (continued) Source Control BMP Applicable Implementation Requirements ~ Paved with an impervious surface ~ Designed not to allow run-on from adjoining areas ~ Screened or walled to prevent off-site transport of trash ~ Common Trash Enclosure and ~ Use trash containers with attached lids to exclude rain Recyclable Material Storage and maintain lids in closed position while not in use Areas and/or include a roof or awning to minimize direct precipitation. ~ Acknowledgment that installation of storm drain inlets or area drains in designated trash storage areas is prohibited D Not Applicable Comment: ~ Plant pest-resistant or well-adapted plant varieties such as drought tolerant and/or native plants ~ Discourage pests by modifying the site and landscaping design ~ Employ Integrated Pest [8] Distribute 1PM educational materials to future occupants as part of the final engineering phase Operation and Management (1PM) Practices Maintenance Plan (O&M Plan) which addresses physical pest elimination techniques such as relying on natural enemies to consume pests, weeding, pruning, and etc. Emphasis placed on correct and limited use of pesticides as a last line of defense D Not Applicable Comment: Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan Page 18 INTERNATIONAL 11.0 Permanent Source Control BMPs (continued) Source Control BMP Applicable Implementation Requirements [8J Employ rain shutoff devices to prevent irrigation during and after precipitation [8J Design irrigation systems for the specific water requirements of each landscape area [8J Use flow reducers or shutoff valves triggered by a [8J Use of Efficient Irrigation pressure drop to control water loss in the event of broken Systems & Drought Tolerant sprinkler heads or lines Landscape [8J Provide water conservation educational materials to Design future occupants as part of final engineering phase Operation and Maintenance Plan (O&M Plan) [8J Acknowledgment that Landscape & Irrigation plan is required to be consistent with City of Carlsbad Water Efficient Landscaping Ordinance D Not Applicable Comment: D Equipped with a clarifier or other pretreatment facility approved by the City Engineer D Properly connected to a sanitary sewer QL D Interior Floor Drains and D An alternate method, as approved by the City Engineer Elevator Shaft Sump Pumps D Acknowledgment that direct connection of interior floor drains and elevator shaft pumps to private or public storm drain or sanitary sewer is not permissible [8J Not Applicable Comment: No elevators are proposed Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan Page 19 INTERNATIONAL 11.0 Permanent Source Control BMPs (continued) Source Control BMP Applicable Implementation Requirements D Prohibit vehicle washing D Prohibit pressuring washing of parking surface in the parking garage and D Provide adequate treatment control BMPs to treat runoff prior to discharge to an MS4 and D Provide prohibitive dumping signage and floor drain marking; prominently displayed inside the parking garage and at the floor drains, respectively and; D Interior Parking Garages D Implement dry clean-up methods for non-hazardous Equipped with Floor Drains accidental spills D Equipped with a clarifier or other pretreatment facility D Properly connected to a sanitary sewer QL D An alternate method, as approved by the City Engineer D Acknowledgment that direct connection of interior floor drains and elevator shaft pumps to the sanitary sewer or storm water conveyance is not permissible [8J Not Applicable Comment: No parking garages proposed DA pet waste station that includes eye level, post mounted signage which reads "pick-up after your pet" or similar D Pet Use Areas approved language and DA pet waste disposal receptacle equipped with a lid [8J Not Applicable Comment: Pet use areas not proposed Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan Page 20 INTERNATIONAL 12.0 Identification of BMPs Applicable to Individual Priority Project Categories Individual Priority Project Applicable Best Management Practice Cate2ory D Rural Swale System D Urban Curb/Swale System D Private Roads D Dual Drainage System D An alternate method, as approved by the City Engineer [8J Not Applicable Comment: Project does not propose any private roads. D Designed to drain into adjacent landscape prior to discharging to a storm water conveyance D Shared access [8J Residential Driveways & Guest D Flared or piano shaped entrance (single lane at street) Parking D Wheelstrips (paving only under tires) [8J Porous paving/Permeable surface D Not Applicable Comment: Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan Page 21 INTERNATIONAL 12.0 Identification of BMPs Applicable to Individual Priority Project Categories ( continued) Individual Priority Project Applicable Implementation Requirements Cateeorv D Covered loading dock areas QL D Designed to preclude urban run-on and runoff D Containment method to isolate dock and facilitate pollutant removal, such as a shut-off valve and containment area D Dock Areas (Truck Wells) D Equipped with a clarifier or other pretreatment facility D An alternate method, as approved by the City Engineer D Acknowledgement that direct connections to storm drains from depressed loading docks are prohibited ~ Not Applicable Comment: Project does not propose any dock areas. D Located indoors and, D Designed to preclude urban run-on and runoff from adjacent areas 0 Self contained bay drainage system (i.e. dead-end sump, with no outlet to offsite facilities) designed to capture all D Maintenance and Repair Bays wash water, leaks, and spills. The self contained drainage system shall connect to a "dead end sump" for collection and proper disposal D Acknowledgement that connection of maintenance and repair bay drains to the sanitary sewer or storm water conveyance system is prohibited. ~ Not Applicable Comment: Project does not propose any maintenance and/or repair bays. Robertson Ranch Recreation Center Priority Development Project -Storm Water Management Plan Page 22 Michael Baker INTERNATIONAL 12.0 Identification of BMPs Applicable to Individual Priority Project Categories ( continued) Individual Priority Project Applicable Best Management Practice Category D Paved with an impervious surface D Self-contained to preclude urban run-on and runoff D Preferably located indoors m:, D Covered with a roof or overhang D Vehicle and Equipment Wash D Equipped with a clarifier or other pretreatment facility Areas D Properly connected to a sanitary sewer QI, D An alternate method, as approved by the City Engineer D Acknowledgement that connection of vehicle and equipment wash areas to the storm water conveyance system is prohibited [81 Not Applicable Comment: Project does not propose any vehicle and/or equipment wash areas. D Cover or enclose areas of that are a source of pollutants, D Grade or berm the perimeter of the processing area to prevent run-on or runoff D Sloped to a self contained drainage system (i.e. "dead-end sump", with no outlet to offsite facilities) designed to capture all wash water, leaks, and spills. The self contained drainage system shall connect to a "dead end sump" for collection and proper disposal D Outdoor Processing Areas D Equipped with a clarifier or other pretreatment facility D Properly connected to a sanitary sewer QI, D An alternate method, as approved by the City Engineer D Acknowledgement that installation of storm drain inlets in outdoor processing areas and connection to a storm water conveyance system is prohibited [81 Not Applicable Comment: Project does not propose any outdoor processing areas. Robertson Ranch Recreation Center Priority Development Project -Storm Water Management Plan Page 23 Michael Baker INTERNATIONAL 12.0 Identification of BMPs Applicable to Individual Priority Project Categories ( continued) Individual Priority Project Applicable Best Management Practice Category D Paved with an impervious PCC surface D Graded at a minimum slope to prevent pond formation D Separated by grade break, curb, or berm to prevent run- on D Covered with a canopy that extends a minimum of ten feet in each horizontal direction, for each pump, or alternatively; D Covered the fuel area with minimum dimensions equal D Fueling Areas to or greater than the area within the grade break or fueling area (defined as extending 6.5 feet from the corner of each fuel dispenser or the length at which each hose and nozzle assembly may be operated plus one foot, whichever is greater D The canopy shall not drain to the fueling area D Acknowledgement that connection of fueling areas to the sanitary sewer or storm water conveyance system is prohibited ~ Not Applicable Comment: Project does not propose any fueling roads. D Where landscaping is proposed in surface parking areas (both covered and uncovered), incorporate landscape areas into the drainage design D Retail and Surface Parking D Overflow parking (i.e. parking in excess of the minimum Areas parking requirements for the project) may be constructed of permeable paving ~ Not Applicable Comment: Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan Page 24 INTERNATIONAL 12.0 Identification of BMPs Applicable to Individual Priority Project Categories ( continued) Individual Priority Project Applicable Best Management Practice Category ~ Steep hillside areas disturbed by project development shall be landscaped with deep rooted, drought-tolerant plant species selected for erosion control and stabilized ~ Steep Hillside Landscaping with mulch, consistent the City Water Efficient Landscaping Ordinance 10-0R0412-1 and the statewide Water Conservation in Landscape Act D Not Applicable Comment: Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan Page 25 INTERNATIONAL 13.0 Implementation of Site Design Low Impact Development (LID) Practices LID Practice Applicable Design Characteristics D Preserve natural drainage features D Preserve existing trees and vegetation D Minimize soil disturbance D Clustering or concentrating development on the least ~ Conserve Natural Areas environmentally sensitive areas; consistent with SUSMP §4.1 (e.g. developing on ... previously graded areas, areas containing of non-native vegetation and etc.) D Incorporation of open space Lot(s) D An alternate method, as approved by the City Engineer D Not Applicable Comment: Landscaped steep slopes will not be disturbed. Otherwise, no landscaping exists onsite. D Minimize the impervious footprint by increasing building density and/or by incorporating multiple- storied architecture ~ Construct streets, sidewalks, and parking lot drive aisles to minimum widths, provided public safety is not compromised ~ Minimize Impervious Surfaces ~ Incorporate landscape buffers between sidewalks, streets, and other flatwork ~ Minimize impervious surfaces in landscape design; such as decorative or stamped concrete ~ Using permeable surfaces (porous concrete, pavers, asphalt) in overflow parking or low-traffic areas D An alternate method, as approved by the City Engineer D Not Applicable Comment: Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan Page 26 INTERNATIONAL 13.0 Implementation of Site Design Low Impact Development (LID) Practices ( continued) LID Practice Applicable Design Characteristic D Minimize disturbance to natural drainages ~ Convey runoff safely from the tops of slopes IX] Vegetate slopes with native or drought tolerant landscape D Protect Slopes and Channels D Stabilize permanent channel crossings D Install Energy Dissipaters D An alternate method, as approved by the City Engineer D Not Applicable Comment: Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan Page 27 INTERNATIONAL 14.0 Tabulation of Drainage Management Areas (DMAs) AREAS DRAINING TO INTEGRATED MANAGEMENT PRACTICES (IMP's) DMA POST-PROJECT AREA RUNOFF (AREA)x NAME SURFACE TYPE (sq ft) FACTOR (RUNOFF IMP-1 FACTOR) Landscape 14,697 0.10 1,470 A Pervious Pa.ement 9,397 0.20 1,879 Bioretention hea Impervious 4,998 1.00 4,998 IMP SIZING FACTOR I MINIMUM AREA(sf) PROPOSED AREA(sf) TOTAL 8,347 0.04 I 334 940 DMA POST-PROJECT AREA RUNOFF (AREA)x NAME SURFACE TYPE (sq ft) FACTOR (RUNOFF IMP-2 FACTOR) B Landscape 4,769 0.10 477 Bioretention hea Impervious 5,284 1.00 5,284 IMP SIZING FACTOR f MINIMUMAREA(sf) PROPOSED AREA (sf) TOTAL 5,761 0.04 I 230 625 DMA POST-PROJECT AREA RUNOFF (AREA)x NAME SURFACE TYPE (sq ft) FACTOR (RUNOFF IMP-3 FACTOR) C Landscape 4,312 0.10 431 Bioretention hea Impervious 5,296 1.00 5,296 IMP SIZING FACTOR I MINIMUMAREA(sf) PROPOSED AREA(sf) TOTAL 5,727 0.04 I 229 880 SELF-TREATING AREAS DMA PERVIOUS AREA IMPERVIOUS AREA % IMPERVIOUS NAME (sq ft) (sq ft) (MUST BE< 5%) D 3,200 165 4.90% Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan Page 28 INTERNATIONAL 15.0 Relative Effectiveness of Project Treatment Facilities Relative Effectiveness of Project Treatment Facilities and I MPs Pollutants Grouped by Method of Transport Treatment Facility /IMP Coarse Pollutants Associated with Pollutants that tend to be Sediment and Trash [8J Bioretention IMP High D Flow Through Planter IMP High D Infiltration IMP High D Conventional Vegetated Swale High D Extended (Dry) Detention High Basins D Media (Sand) Filter High D Wet Pond High D Constructed Wetland High D Proprietary Vault/Tree Well High D Proprietary Inlet Filter (as part of treatment train in Self-High Treating areas A and B, See BMP Map for location] Robertson Ranch Recreation Center Priority Development Project -Storm Water Management Plan Page 29 Fine Particles During Dissolved Following Transport Treatment High Medium High Medium High High Medium Low High Low High Low High Medium High Medium Medium Low Low Low Michael Baker INTERNATIONAL 16.0 Projected Storm Water BMP Maintenance Mechanism Maintenance Mechanism D Conditional Use Permit -For discretionary projects only, the City may assure maintenance of storm water BMPs through the inclusion of maintenance conditions in the conditional use permit. A non-refundable security may be required. D Project Proponent Agreement to Maintain Storm Water BMPs -The City may enter into a contract with the project proponent obliging the project proponent to maintain, repair and replace the storm water BMP as necessary into perpetuity. A non-refundable security may be required. D Lease Provision -In those cases where the City holds title to the land in question and the land is being leased to another party for private or public use, the City may assure storm water BMP maintenance, repair and replacement through conditions in the lease. D Assessment District -The City may approve an Assessment District or other funding mechanism created by the project proponent to provide funds for storm water BMP maintenance, repair and replacement on an ongoing basis. Any agreement with such a District shall be subject to the Public Entity Maintenance Provisions below. D Public Entity Maintenance -The City may approve a public or acceptable quasi-public entity (e.g., the County Flood Control District, or annex to an existing assessment district, an existing utility district, a state or federal resource agency, or a conservation conservancy) to assume responsibility for maintenance, repair and replacement of the BMP. Public entity maintenance agreements shall ensure estimated costs and front-funded or reliably guaranteed, (e.g., through a trust fund, assessment district, fees, bond, letter of credit or similar means). In addition, the City may seek protection from liability by appropriate releases and indemnities. The City Engineer shall have the authority to approve storm water BMPs proposed for transfer to any other public entity within its jurisdiction before installation. The City shall be involved in the negotiation of maintenance requirements with any other public entities accepting maintenance responsibilities within their respective jurisdictions; and in negotiations with the resource agencies responsible for issuing permits for the construction and/ or maintenance of the facilities. The City must be identified as a third party beneficiary empowered to enforce any such maintenance agreement within their respective jurisdictions. D Alternative Mechanism -The City may accept an alternative maintenance mechanism if such mechanism is as protective as those listed above. An alternative mechanism must be approved by the City Attorney and the City Engineer. Comment: Robertson Ranch Recreation Center Priority Development Project -Storm Water Management Plan Page 30 Michael Baker INTERNATIONAL 17.0 Summary and Conclusion Narrative Water Quality requirements outlined in the City of Carlsbad SUSMP (January 2011) will be met by implementing BMPs including landscape areas, bioretention, and pervious paving. Locations, quantities, and supporting calculations can be found on the attached BMP Map. Hydromodification requirements outlined in the City of Carlsbad SUSMP (January 2011) will be met to ensure that "post-development runoff rates and durations do not exceed pre-project conditions." Hydromodification controls that will be implemented include landscape areas, bioretention and pervious paving. Locations, quantities, and supporting calculations can be found on the attached BMP Map and Hydromodification Calculations. Robertson Ranch Recreation Center Priority Development Project -Storm Water Management Plan Page 31 Michael Baker INTERNATIONAL 18.0 Figures • Vicinity Map • Soil Type Exhibit • Federal Emergency Management Agency (FEMA) Map • BMPMap Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan INTERNATIONAL I I 0 '-::l' i g § .. I !a v \ I \ 'oJ> [ill](;) ~ • ca,tsbad ftogh School " , l.,bad • I \ \ ~ ... 1\. I ... ~ Creek High Schoo \rost"'~ I I I I VICINITY MAP I I I I Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan INTERNATIONAL NRCS SOIL SURVEY Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan INTERNATIONAL I I I I I I I I I USDA ??:: United States Department of Agriculture NRCS Natural Resources Conservation Service A product of the National Custom Soil Resource Cooperative Soil Survey, a joint effort of the United Report for States Department of San Diego County Agriculture and other Federal agencies, State agencies including the Area, California Agricultural Experiment Stations, and local participants February 19, 2015 33" 9'13"N 33" 9'10"N I 6! M ~ I l:l ~ l:l ~ 3: ~ !!! 9 ;~ i- 3: ~ !!! - I 471500 9 A - ------ --Custom Soil Resource Report Soil Map 471510 471520 4715JO 471540 471550 471560 471Si0 Map Scale: 1: 548 f prrted on A lilndscape (11° X 8.5") sheet -----====---------<========~Meters o s ro ~ ~ 0--------25=========50""""" _____________ 1000::::::=============.1;:« Map prQjedion: Web MeroltDr Comer CllOl'dinates: WGS84 Edge tics: lJTM Zone 11N WGS84 8 ---- 471580 471590 471600 - 471610 I 471610 3: !!I !!! 9 3: !!I !!I 9 -- 33" 9' 13"N I I I I I I i 33" 9'10"N --- - -- - - --Custom Soil Resource Report MAP LEGEND Area of Interest (AOI) D Area of Interest (AOI) Solla LJ Soil Map Unit Polygons Soil Map Unit Lines Cl Soil Map Unit Points Speclal Point Features w Blowout 181 Borrow Pit • Clay Spot <> Closed Depression ;x; Gravel Pit . Gravelly Spot .. 0 Landfill A. Lava Flow .w, Marsh or swamp ~ Mine or Quarry 0 Miscellaneous Water 0 Perennial Water V Rock Outcrop + Saline Spot .. Sandy Spot . . . * Severely Eroded Spot 0 Sinkhole 3t Slide or Slip JI/ SodicSpot ~ Spoil Area 0 Stony Spot a, Very Stony Spot ~ Wet Spot 6 Other ... Special Line Features Water Features Streams and Canals Transportation +++ ,,..,,, ,,..,,, Rails Interstate Highways US Routes Major Roads Local Roads Background • Aerial Photography 9 - -- --c::::a MAP INFORMATION The soil surveys that comprise your AOI were mapped at 1 :24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale . Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: http://websoilsurvey.nrcs.usda.gov Coordinate System: Web Mercator {EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date{s) listed below. Soil Survey Area: Survey Area Data: San Diego County Area, California Version 8, Sep 17, 2014 Soil map units are labeled (as space allows) for map scales 1 :50,000 or larger . Date{s) aerial images were photographed: May 3, 2010-Jun 19, 2010 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting .-4._---.. -.:.& L-.--..1--!----·· L-----vrTtfa),'UTm. DUUIIUUIICJ illdj DC CIIQCIIC. Custom Soil Resource Report Map Unit Legend San Diego County Area, California (CA638) Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI LeC2 Las Flores loamy fine sand, 5 to 1.2 9 percent slopes, erod ed ---------------------- LeE3 Las Flores loamy fine sand, 9 to 0.0 30 percent slopes, severely eroded ----~----------- Totals for Area of Interest 1.2 ----·---------------- Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If 10 ---- 99.1% -~-- 0.9% ------ 100.0% Custom Soil Resource Report intensive use of small areas is planned, however, onsite investigation is needed to define and locate the soils and miscellaneous areas. An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps. The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha-Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha- Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. 11 Custom Soil Resource Report San Diego County Area, California LeC2-Las Flores loamy fine sand, 5 to 9 percent slopes, erod ed Map Unit Setting National map unit symbol: hbd9 Elevation: 700 feet Mean annual precipitation: 12 inches Mean annual air temperature: 61 degrees F Frost-free period: 300 to 340 days Farmland classification: Farmland of statewide importance Map Unit Composition Las flares and similar soils: 85 percent Minor components: 15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Las Flores Setting Landform: Hillslopes Landform position (two-dimensional): Backslope Landform position (three-dimensional): Side slope Down-slope shape: Convex Across-slope shape: Convex Parent material: Residuum weathered from siliceous calcareous sandstone Typical profile H1 -0 to 14 inches: loamy fine sand H2 -14 to 22 inches: sandy clay, clay H2 -14 to 22 inches: sandy clay, clay H3 -22 to 38 inches: loamy coarse sand H3 -22 to 38 inches: weathered bedrock H4 -38 to 48 inches: H5 -48 to 52 inches: Properties and qualities Slope: 5 to 9 percent Depth to restrictive feature: 40 to 60 inches to paralithic bedrock Natural drainage class: Moderately well drained Runoff class: Very high Capacity of the most limiting layer to transmit water (Ksat): Very low to moderately low (0.00 to 0.06 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Sodium adsorption ratio, maximum in profile: 39.0 Available water storage in profile: Low (about 4.3 inches) Interpretive groups Land capability classification (irrigated): 3e Land capability classification (nonirrigated): 4e Hydrologic Soil Group: D Ecological site: Claypan (1975) (R019XD061 CA) 12 Custom Soil Resource Report Minor Components Huerhuero Percent of map unit: 5 percent Linne Percent of map unit: 5 percent Diablo Percent of map unit: 3 percent Unnamed, ponded Percent of map unit: 2 percent Landform: Depressions LeE3-Las Flores loamy fine sand, 9 to 30 percent slopes, sev erely eroded Map Unit Setting National map unit symbol: hbdg Elevation: 700 feet Mean annual precipitation: 12 inches Mean annual air temperature: 61 degrees F Frost-free period: 300 to 340 days Farmland classification: Not prime farmland Map Unit Composition Las flares and similar soils: 85 percent Minor components: 15 percent Estimates are based on observations, descriptions, and transer.ts of the mapunit. Description of Las Flores Setting Landform: Hillslopes Landform position (two-dimensional): Backslope Landform position (three-dimensional): Side slope Down-slope shape: Convex Across-slope shape: Convex Parent material: Residuum weathered from siliceous calcareous sandstone Typical profile H1 -0 to 14 inches: loamy fine sand H2 -14 to 22 inches: sandy clay, clay H2 -14 to 22 inches: sandy clay, clay H3 -22 to 38 inches: loamy coarse sand H3 -22 to 38 inches: weathered bedrock H4 -38 to 48 inches: H5 -48 to 52 inches: 13 Custom Soil Resource Report Properties and qualities Slope: 9 to 30 percent Depth to restrictive feature: 40 to 60 inches to paralithic bedrock Natural drainage class: Moderately well drained Runoff class: Very high Capacity of the most limiting layer to transmit water (Ksat): Very low to moderately low (0.00 to 0.06 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Sodium adsorption ratio, maximum in profile: 30.0 Available water storage in profile: Low (about 4.3 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 6e Hydrologic Soil Group: D Ecological site: Claypan (1975) (R019XD061 CA) Minor Components Diablo Percent of map unit: 5 percent Huerhuero Percent of map unit: 5 percent Linne Percent of map unit: 5 percent 14 FEMAMAP Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan INTERNATIONAL •• I' 11 ,1 'ii, 1, ,, · I· 11 I ; .... 1!!1! '1 rv J !l I I 1 'l •' 'I, I I : !I I I I BMPMAP Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan INTERNATIONAL 2_8+00 '·' '!': .~·----- , ' ~ -· .-. ----c;,--·· n: _[2" FREEBOARD 4" PONDING ( V 1 STORAGE) BIORETENTION AREA NTS --[,7777777 ,,77,77;7/. · ... f,; . . . . . . r , , ," f;"" ·• e? t' . ·· .•... r::,///. 'y .I ,-~~~ .. I BMP ID # BMP TYPE SYMBOL CASQA NO. QUANT !TY TREATMENT CONTROL CD B !ORETENT! ON AREA BIORETENTION AREA BI ORETENTI ON AREA BIORETENTION AREA 1 · . . . . J . . . . . . . . . . 1 · · · · · I . . . . . . . . . . L ···I . . . . . . . . . . 1 · · · · · I . . . . . . . . . . TC-32 880 SF TC-32 625 SF TC-32 450 SF TC-32 490 SF BMP TABLE DRAWING NO. SHEET NO. (S) 480-38 6 480-38 6 480-38 6 480-38 6 INSPECTION FREQUENCY AFTER STORM EVENTS AFTER STORM EVENTS AFTER STORM EVENTS AFTER STORM EVENTS MAINTENANCE FREQUENCY BI-ANNUAL BI-ANNUAL BI-ANNUAL BI-ANNUAL CONSTRUCTION SIGN OFF ; h-.,.. ,-,_· v-cc'.-------t-SD --- LOW IMPACT DESIGN (L.I.D.) ® PERMEABLE PAYERS AFTER STORM EVENTS co ,;(f),;:,,\. ~•,J·· .. ,DMA . :.:i(_f,,"'.i·;·<(::'·, B ····-!· ~----~ ·• -·· ~ --;'"'?< ,-,%+;· ' ---1 : ... []{i\ ' . . • ··1 . . <)~;)p{"c---_ LEGEND PROPOSED I MPERV JOUS AREA I : . --1 , ,_-~ l''T::1,----1 PROPOSED PERVIOUS PAVEMENT nP:iDf'-9lf'o PROPOSED BIORETENTION PROPOSED STORM DRAIN ,. .., ·. '' 1· . . . . I . . . . . . . . . . ..... EXISTING STORM DRAIN -----,,r,~-, DMA AREA·····- LEGEND CJ) COMPACTED SUBGRADE (]) PLANTING PER LANDSCAPE PLANS 0 24" BIO-FILTRATJON SOIL LAYER (SANDY LOAM WITH MINIMUM INFILTRATION RATE~ 5 IN/HR) 3" WASHED PEA GRAVEL 4" PERFORATED PVC DRAIN PIPE ~ IMPERMEABLE LINER ON SIDES ® 12" CLASS 2 PERMEABLE BASE CD ® ® GRATE INLET CATCH BASIN. TOP OF GRATE 4" ABOVE FINISH GRADE. SEE OUTLET STRUCTURE DETAIL HEREON. R/W---- d'·) V1 STORAGE PER DETAIL HEREON\ SD-20 SOURCE CONTROL SWMP NO.: 15-15 MA I NTENANCE AGREEMENT DOCUMENT: YES No RECORDAT I ON NO.: ____ _ PARTY RESPONSIBLE FOR MAINTENANCE: NAME: TOLL BROTHERS CONTACT, GREG DEACON ADDRESS: 725 WEST TOWN AND COUNTRY ROAD . SU !TE 200 ORANGE. CA 92868 PHONE NO.: 760-720-5485 PLAN PREPARED BY: NAME: DAVID WIENER COMPANY, MICHAEL BAKER INTERNATIONAL ADDRESS: 5050 AVENIDA ENCINAS, SUITE 260 CARLSBAD, CA 92008 PHONE NO.: 760-476-9193 CERTIFICATION: RCE #77285 CATCH BASIN PER PLAN SOIL MIX PER DETAIL HEREON 1 ~---.--,==cc=n":-: T 6 .. 6" PERFORATED UNDERDRAIN MIPT PVC ADAPTER CAST IN SIDE OF CATCH BASIN FLOW REMOVABLE FIPT PVC CAP WITH DRILLED ORIFICE HOLE, ORIFICE SIZE = 0.5" rOUTFALL PIPE PER PLAN J='-==.b-, FLOW ~ BIORETENTION AREA OUTLET STRUCTURE DETAIL NTS 8.940 SF 480-38 6 QUARTERLY BMP NOTES: 1. THESE BMPS ARE MANDATORY TO BE INSTALLED PER MANUFACTURER'S RECOMMENDATIONS OR PLANS. 2. NO CHANGES TO THE PROPOSED BMPS ON THIS SHEET WITHOUT PRIOR APPROVAL FROM THE CITY ENGINEER. 3. NO SUBSTITUTIONS TO THE MATERIAL OR TYPES OR PLANTING TYPES WITHOUT PRIOR APPROVAL FROM THE CITY ENGINEER. 4. NO OCCUPANCY WILL BE GRANTED UNTIL THE CITY INSPECTION STAFF HAS INSPECTED THIS PROJECT FOR APPROPRIATE BMP CONSTRUCT! ON AND INST ALLAT JON. BELGARD ECO DUBLIN PERMEABLE PAVING SYSTEM* COLOR PER LANDSCAPE PLAN .,----JOINT & VOID FILLER * // 1.5"-2" NO. 8 DRAINAGE AGGREGATE* CLASS 2 PERMEABLE BASE COMPACTED TO 95% * 12" MIN. MIRAFI 140N OVER 15 mi I IMPERMEABLE MEMBRANE. 4" PERFORATED PVC DRAIN PIPE SURROUNDED BY 3 .. PERMEABLE BASE * PERMEABLE PAVING SYSTEM AND BASE COURSE TO BE APPROVED BY MANUFACTURER PRIOR TO INSTALLATION PERVIOUS UNIT PAVER DETAIL NTS ROBERTSON RANCH RECREATION CENTER BMPMAP INTERNATIONAL 5050 Avenida Encinas, Suite 260 Carlsbad. CA 92008 Phone, (760) 476-9·193 WWW.MBAKERINTL.COM C, 0 •c u 19.0 Attachments • Storm Water Standards Questionnaire • Hydromodification Calculations • BMP Fact Sheets Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan INTERNATIONAL STORM WATER STANDARDS QUESTIONNAIRE Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan INTERNATIONAL (_ City of Carlsbarl STORM WATER STANDARDS QUESTIONNAIRE E-34 Development Services Land Development Engineering 1635 Faraday Avenue 760-602-2750 www.carlsbadca.gov To address post-development pollutants that may be generated from development projects, the City requires that new development and significant redevelopment priority projects incorporate Permanent Storm Water Best Management Practices (BMP's) into the project design per the City's Standard Urban Stormwater Management Plan (SUSMP). To view the SUSMP, refer to the Engineering Standards (Volume 4, Chapter 2). Initially this questionnaire must be completed by the applicant in advance of submitting for a development application (subdivision, discretionary permits and/or construction permits). The results of the questionnaire determine the level of storm water standards that must be applied to a proposed development or redevelopment project. Depending on the outcome, your project will either be subject to 'Standard Stormwater Requirements' or be subject to additional criteria called 'Priority Development Project Requirements'. Many aspects of project site design are dependent upon the storm water standards applied to a project. Your responses to the questionnaire represent an initial assessment of the proposed project conditions and impacts. City staff has responsibility for making the final assessment after submission of the development application. If staff determines that the questionnaire was incorrectly filled out and is subject to more stringent storm water standards than initially assessed by you, this will result in the return of the development application as incomplete. In this case, please make the changes to the questionnaire and resubmit to the City. If you are unsure about the meaning of a question or need help in determining how to respond to one or more of the questions, please seek assistance from Land Development Engineering staff. A separate completed and signed questionnaire must be submitted for each new development application submission. Only one completed and signed questionnaire is required when multiple development applications for the same project are submitted concurrently. In addition to this questionnaire, you must also complete, sign and submit a Project Threat Assessment Form with construction permits for the project. Please start by completing Step 1 and follow the instructions. When completed, sign the form at the end and submit this with your application to the city. STEP 1 TO BE COMPLETED FOR ALL PROJECTS To determine if your project is a priority development project, please answer the following questions: YES NO 1. Is your project LIMITED TO constructing new or retrofitting paved sidewalks, bicycle lanes or trails that meet the following criteria: (1) Designed and constructed to direct storm water runoff to adjacent vegetated areas, or X other non-erodible permeable areas; OR (2) designed and constructed to be hydraulically disconnected from paved streets or roads; OR (3) designed and constructed with permeable pavements or surfaces in accordance with USEPA Green Streets guidance? 2. Is your project LIMITED TO retrofitting or redeveloping existing paved alleys, streets, or roads that are designed and constructed in accordance with the USEPA Green Streets guidance? X If you answered "yes" to one or more of the above questions, then your project is NOT a priority development project and therefore is NOT subject to the storm water criteria required for priority development projects. Go to step 4, mark the last box stating "my project does not meet PDP requirements" and complete applicant information. If you answered "no" to both questions, then go to Step 2. E-34 Page 1 of 3 Effective 6/27 /13 ,· l_ City of -:arlsbad STORM WATER STANDARDS QUESTIONNAIRE E-34 Development Services Land Development Engineering 1635 Faraday Avenue 760-602-2750 www.carlsbadca.gov STEP2 TO BE COMPLETED FOR ALL NEW OR REDEVELOPMENT PROJECTS To determine if your project is a priority development project, please answer the following questions: YES 1. Is your project a new development that creates 10,000 square feet or more of impervious surfaces collectively over the entire project site? This includes commercial, industrial, residential, mixed-use, and public X development proiects on public or private land. 2. Is your project creating or replacing 5,000 square feet or more of impervious surface collectively over the entire project site on an existing site of 10,000 square feet or more of impervious surface? This includes commercial, industrial, residential, mixed-use, and public development projects on public or private land. 3. Is your project a new or redevelopment project that creates 5,000 square feet or more of impervious surface collectively over the entire project site and supports a restaurant? A restaurant is a facility that sells prepared foods and drinks for consumption, including stationary lunch counters and refreshment stands selling prepared foods and drinks for immediate consumption. 4. Is your project a new or redevelopment project that creates 5,000 square feet or more of impervious surface collectively over the entire project site and supports a hillside development project? A hillside development project includes development on any natural slope that is twenty-five percent or greater. 5. Is your project a new or redevelopment project that creates 5,000 square feet or more of impervious surface collectively over the entire project site and supports a parking lot. A parking lot is a land area or facility for the X temporary parking or storage of motor vehicles used personally for business or for commerce. 6. Is your project a new or redevelopment project that creates 5,000 square feet or more of impervious surface collectively over the entire project site and supports a street, road, highway freeway or driveway? A street, road, highway, freeway or driveway is any paved impervious surface used for the transportation of automobiles, trucks, motorcycles, and other vehicles. 7. Is your project a new or redevelopment project that creates or replaces 2,500 square feet or more of impervious surface collectively over the entire site, and discharges directly to an Environmentally Sensitive Area (ESA)? "Discharging Directly to" includes flow that is conveyed overland a distance of 200 feet or less from the project to the ESA, or conveyed in a pipe or open channel any distance as an isolated flow from the project to the ESA (i.e. not comminq/es with flows from adjacent lands).* 8. Is your project a new development that supports an automotive repair shop? An automotive repair shop is a facility that is categorized in any one of the following Standard Industrial Classification (SIC) codes: 5013, 5014, 5541, 7532-7534, or 7536-7539. 9. Is your project a new development that supports a retail gasoline outlet (RGO)? This category includes RGO's that meet the following criteria: (a) 5,000 square feet or more or (b) a project Average Daily Traffic (ADT) of 100 or more vehicles per day. 1 O. ls your project a new or redevelopment project that results in the disturbance of one or more acres of land and X are expected to generate pollutants post construction? 11. ls your project located within 200 feet of the Pacific Ocean and (1) creates 2,500 square feet or more of impervious surface or (2) increases impervious surface on the property by more than 10%? NO X X X X X X X X If you answered "yes" to one or more of the above questions, you ARE a priority development project and are therefore subject to implementing structural Best Management Practices (BMP's) in addition to implementing Standard Storm Water Requirements such as source control and low impact development BMP's. A Storm Water Management Plan (SWMP) must be submitted with your application(s) for development. Go to step 3 for redevelopment projects. For new projects, go to step 4 at the end of this questionnaire, check the "my project meets PDP requirements" box and complete applicant information. If you answered "no" to all of the above questions, you ARE NOT a priority development project and are therefore subject to implementing only Standard Storm Water Requirements such as source control and low impact development BMP's required for all development projects. A Storm Water Management Plan (SWMP) is not required with your application(s) for development. Go to step 4 at the end of this questionnaire, check the "my project does not meet PDP requirements" box and complete applicant information. E-34 Page 2 of 3 Effective 6/27 / 13 (_ <=ity of -:arlsbali STORM WATER STANDARDS QUESTIONNAIRE E-34 STEP3 Development Services Land Development Engineering 1635 Faraday Avenue 760-602-2750 www.carlsbadca.gov TO BE COMPLETED FOR REDEVELOPMENT PROJECTS THAT ARE PRIORITY DEVELOPEMENT PROJECTS ONLY Complete the questions below regarding your redevelopment project: YES Does the redevelopment project result in the creation or replacement of impervious surface in an amount of less than I I 50% of the surface area of the previously existinq development? If you answered "yes," the structural BMP's required for Priority Development Projects apply only to the creation or replacement of impervious surface and not the entire development. Go to step 4, check the "my project meets PDP requirements" box and complete applicant information. NO If you answered "no," the structural BMP's required for Priority Development Projects apply to the entire development. Go to step 4, check the "mv project meets PDP requirements" box and complete applicant information. STEP4 CHECK THE APPROPRIATE BOX AND COMPLETE APPLICANT INFORMATION My project meets PRIORITY DEVELOPMENT PROJECT (PDP) requirements and must comply with additional stormwater criteria per the SUSMP and I understand I must prepare a Storm Water Management Plan for submittal at time of application. I understand flow control (hydromodification) requirements may apply to my project. Refer to SUSMP for details. 0 My project does not meet PDP requirements and must only comply with STANDARD STORMWATER REQUIREMENTS per the SUSMP. As part of these requirements, I will incorporate low impact development strategies throughout my project. Applicant Information and Sig_nature Box MICHAEL BAKER INTERNATIONAL Address: 5050 AVENIDA ENCINAS, SUITE 260 CARLSBAD CA 92008 Applicant Name: DAVID WIENER PE ' . . _A_P_Pl-ic_a_n_t _s_ig_n_at_u_re_:_ ,(_y-:J) ~ ___ _ Accessor's Parcel Number(s): 208_010-44 Applicant Title: PROJECT ENGINEER Date: 7/21/2015 This Box for City Use Only City Concurrence: I YES I NO I I By: Date: Project ID: * Environmentally Sensitive Areas include but are not limited to all Clean Water Act Section 303(d) impaired water bodies; areas designated as Areas of Special Biological Significance by the State Water Resources Control Board (Water Quality Control Plan for the San Diego Basin (1994) and amendments); water bodies designated with the RARE beneficial use by the State Water Resources Control Board (Water Quality Control Plan for the San Diego Basin (1994) and amendments); areas designated as preserves or their quivalent under the Multi Species Conservation Program within the Cities and County of San Diego; and any other equivalent environmentally sensitive areas which have been identified by the Copermittees. E-34 Page 3 of 3 Effective 6/27 I 13 SOHM HYDROMODIFICATION CALCULATIONS Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan INTERNATIONAL SDHM PROJECT REPORT General Model Information Project Name: REC CENTER Site Name: RR REC CENTER Site Address: City: CARLSBAD Report Date: 3/3/2015 Gage: OCEANS ID Data Start: 10/01/1959 Data End: 09/30/2004 Timestep: Hourly Precip Scale: 1.00 Version: 2015/02/27 POC Thresholds Low Flow Threshold for POC 1 : High Flow Threshold for POC1: REC CENTER 10 Percent of the 2 Year 10 Year 3/3/2015 3:33:08 PM Page 2 Landuse Basin Data Predeveloped Land Use EXISTING Bypass: No GroundWater: No Pervious Land Use Acres D ,Grass,STEEP( 10-20 1.2 Pervious Total 1.2 Impervious Land Use Acres Impervious Total 0 Basin Total 1.2 Element Flows To: Surface lnterflow REC CENTER Groundwater 3/3/2015 3:33:08 PM Page 3 Mitigated Land Use OMA A -LANDSCAPING Bypass: GroundWater: No No Pervious Land Use Acres D,Grass,FLAT(0-5%) .315 Element Flows To: Surface lnterflow Groundwater OMA A-PERVIOUS FW\11~1\.4&-AERVIOUS PAVEMENT REC CENTER 3/3/2015 3 33 08 PM Page 4 OMA A -IMPERVIOUS Bypass: Impervious Land Use IMPERVIOUS-FLAT LAT Element Flows To: No Acres 0.115 Outlet 1 Outlet 2 OMA A -PERVIOUS PAVEMENT REC CENTER 3/3/2015 3 33 08 PM Page 5 DMAB Bypass: No GroundWater: No Pervious Land Use Acres D,Grass,FLAT(0-5%) 0.11 Pervious Total 0.11 Impervious Land Use Acres IMPERVIOUS-FLAT 0.121 Impervious Total 0.121 Basin Total 0.231 Element Flows To: Surface lnterflow Groundwater Surface IMP-2 Surface IMP-2 REC CENTER 3/3/2015 3 33:08 PM Page 6 DMAC Bypass: No GroundWater: No Pervious Land Use Acres D,Grass,FLAT(0-5%) 0.099 Pervious Total 0.099 Impervious Land Use Acres IMPERVIOUS-FLAT 0.122 Impervious Total 0.122 Basin Total 0.221 Element Flows To: Surface lnterflow Groundwater Surface IMP-3 Surface IMP-3 REC CENTER 3/3/2015 3:33:08 PM Page 7 DMAD Bypass: Yes GroundWater: No Pervious Land Use Acres D,Grass,FLAT(0-5%) 0.037 D,Grass,STEEP(10-20 0.036 Pervious Total 0.073 Impervious Land Use Acres IMPERVIOUS-FLAT 0.004 Impervious Total 0.004 Basin Total 0.077 Element Flows To: Surface lnterflow Groundwater REC CENTER 3/3/2015 3:33:08 PM Page 8 Routing Elements Predeveloped Routing REC CENTER 3/3/2015 3:33:08 PM Page 9 Mitigated Routing OMA A -PERVIOUS PAVEMENT Pavement Area:0.2204 ac.Pavement Length: Pavement Width: Pavement thickness: Pour Space of Pavement: Material thickness of second layer: Pour Space of material for second layer: Material thickness of third layer: Pour Space of material for third layer: Element Flows To: Outlet 1 Outlet 2 Surface IMP-1 Porous Pavement Hydraulic Table 240.00 ft. 40.00 ft. Pavement slope 1 :0 To 1 0.33 0.4 2 0.4 0 0 Stage(ft) Area(ac) Volume(ac-ft) Discharge(cfs) lnfilt(cfs) 0.0000 0.220 0.000 0.000 0.000 0.0314 0.220 0.002 0.000 0.000 0.0629 0.220 0.005 0.000 0.000 0.0943 0.220 0.008 0.000 0.000 0.1258 0.220 0.011 0.000 0.000 0.1572 0.220 0.013 0.000 0.000 0.1887 0.220 0.016 0.000 0.000 0.2201 0.220 0.019 0.000 0.000 0.2516 0.220 0.022 0.000 0.000 0.2830 0.220 0.024 0.000 0.000 0.3144 0.220 0.027 0.000 0.000 0.3459 0.220 0.030 0.000 0.000 0.3773 0.220 0.033 0.001 0.000 0.4088 0.220 0.036 0.001 0.000 0.4402 0.220 0.038 0.002 0.000 0.4717 0.220 0.041 0.002 0.000 0.5031 0.220 0.044 0.002 0.000 0.5346 0.220 0.047 0.003 0.000 0.5660 0.220 0.049 0.003 0.000 0.5974 0.220 0.052 0.003 0.000 0.6289 0.220 0.055 0.003 0.000 0.6603 0.220 0.058 0.003 0.000 0.6918 0.220 0.061 0.003 0.000 0.7232 0.220 0.063 0.004 0.000 0.7547 0.220 0.066 0.004 0.000 0.7861 0.220 0.069 0.004 0.000 0.8176 0.220 0.072 0.004 0.000 0.8490 0.220 0.074 0.004 0.000 0.8804 0.220 0.077 0.004 0.000 0.9119 0.220 0.080 0.005 0.000 0.9433 0.220 0.083 0.005 0.000 0.9748 0.220 0.085 0.005 0.000 1.0062 0.220 0.088 0.005 0.000 1.0377 0.220 0.091 0.005 0.000 1.0691 0.220 0.094 0.005 0.000 1.1006 0.220 0.097 0.005 0.000 1.1320 0.220 0.099 0.005 0.000 1.1634 0.220 0.102 0.006 0.000 REC CENTER 3/3/2015 3 33 08 PM Page 10 1.1949 0.220 0.105 0.006 0.000 1.2263 0.220 0.108 0.006 0.000 1.2578 0.220 0.110 0.006 0.000 1.2892 0.220 0.113 0.006 0.000 1.3207 0.220 0.116 0.006 0.000 1.3521 0.220 0.119 0.006 0.000 1.3836 0.220 0.122 0.006 0.000 1.4150 0.220 0.124 0.006 0.000 1.4464 0.220 0.127 0.006 0.000 1.4779 0.220 0.130 0.007 0.000 1.5093 0.220 0.133 0.007 0.000 1.5408 0.220 0.135 0.007 0.000 1.5722 0.220 0.138 0.007 0.000 1.6037 0.220 0.141 0.007 0.000 1.6351 0.220 0.144 0.007 0.000 1.6666 0.220 0.146 0.007 0.000 1.6980 0.220 0.149 0.007 0.000 1.7294 0.220 0.152 0.007 0.000 1.7609 0.220 0.155 0.007 0.000 1.7923 0.220 0.158 0.007 0.000 1.8238 0.220 0.160 0.008 0.000 1.8552 0.220 0.163 0.008 0.000 1.8867 0.220 0.166 0.008 0.000 1.9181 0.220 0.169 0.008 0.000 1.9496 0.220 0.171 0.008 0.000 1.9810 0.220 0.174 0.008 0.000 2.0124 0.220 0.177 0.008 0.000 2.0439 0.220 0.180 0.008 0.000 2.0753 0.220 0.182 0.008 0.000 2.1068 0.220 0.185 0.008 0.000 2.1382 0.220 0.188 0.008 0.000 2.1697 0.220 0.191 0.008 0.000 2.2011 0.220 0.194 0.009 0.000 2.2326 0.220 0.196 0.009 0.000 2.2640 0.220 0.199 0.009 0.000 2.2954 0.220 0.202 0.009 0.000 2.3269 0.220 0.205 0.009 0.000 2.3583 0.220 0.212 0.009 0.000 2.3898 0.220 0.219 0.009 0.000 2.4212 0.220 0.225 0.009 0.000 2.4527 0.220 0.232 0.009 0.000 2.4841 0.220 0.239 0.009 0.000 2.5156 0.220 0.246 0.009 0.000 2.5470 0.220 0.253 0.009 0.000 2.5784 0.220 0.260 0.009 0.000 2.6099 0.220 0.267 0.009 0.000 2.6413 0.220 0.274 0.010 0.000 2.6728 0.220 0.281 0.010 0.000 2.7042 0.220 0.288 0.010 0.000 2.7357 0.220 0.295 0.010 0.000 2.7671 0.220 0.302 0.010 0.000 2.7986 0.220 0.309 0.010 0.000 2.8300 0.220 0.316 0.010 0.000 REC crnTER 3/3/2015 3 33 08 PM Page 11 IMP-1 Bottom Length: Bottom Width: Material thickness of first layer: Material type for first layer: Material thickness of second layer: Material type for second layer: Material thickness of third layer: Material type for third layer: Underdrain used Underdrain Diameter (ft): Orifice Diameter (in): Offset (in): Flow Through Underdrain (ac-ft): Total Outflow (ac-ft): Percent Through Underdrain: Discharge Structure Riser Height: 0.33 ft. Riser Diameter: 12 in. Element Flows To: Outlet 1 Outlet 2 Landscape Swale Hydraulic Table Stage(ft) 0.0000 0.0385 0.0769 0.1154 0.1538 0.1923 0.2308 0.2692 0.3077 0.3462 0.3846 0.4231 0.4615 0.5000 0.5385 0.5769 0.6154 0.6538 0.6923 0.7308 0.7692 0.8077 0.8462 0.8846 0.9231 0.9615 1.0000 1.0385 1.0769 1.1154 1.1538 Area(ac) 0.0393 0.0393 0.0390 0.0388 0.0385 0.0383 0.0381 0.0378 0.0376 0.0373 0.0371 0.0369 0.0366 0.0364 0.0362 0.0359 0.0357 0.0354 0.0352 0.0350 0.0347 0.0345 0.0342 0.0340 0.0338 0.0335 0.0333 0.0331 0.0328 0.0326 0.0323 Volume(ac-ft) 0.0000 0.0002 0.0003 0.0005 0.0007 0.0008 0.0010 0.0012 0.0013 0.0015 0.0017 0.0019 0.0022 0.0026 0.0030 0.0033 0.0037 0.0041 0.0045 0.0049 0.0053 0.0057 0.0061 0.0065 0.0069 0.0073 0.0077 0.0081 0.0085 0.0089 0.0094 45.00 ft. 20.00 ft. 2 Sandy loam 1 GRAVEL 0 GRAVEL 0.5 0.5 0 5.733 5.742 99.84 Discharge(cfs) lnfilt(cfs) 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0009 0.0000 0.0010 0.0000 0.0012 0.0000 0.0012 0.0000 0.0014 0.0000 0.0017 0.0000 0.0018 0.0000 0.0019 0.0000 0.0021 0.0000 0.0023 0.0000 0.0025 0.0000 0.0027 0.0000 0.0028 0.0000 0.0030 0.0000 0.0031 0.0000 0.0032 0.0000 0.0034 0.0000 0.0035 0.0000 0.0036 0.0000 0.0037 0.0000 0.0038 0.0000 REC CENTER 3/3/2015 3 33:08 PM Page 12 1.1923 1.2308 1.2692 1.3077 1.3462 1.3846 1.4231 1.4615 1.5000 1.5385 1.5769 1.6154 1.6538 1.6923 1.7308 1.7692 1.8077 1.8462 1.8846 1.9231 1.9615 2.0000 2.0385 2.0769 2.1154 2.1538 2.1923 2.2308 2.2692 2.3077 2.3462 2.3846 2.4231 2.4615 2.5000 2.5385 2.5769 2.6154 2.6538 2.6923 2.7308 2.7692 2.8077 2.8462 2.8846 2.9231 2.9615 3.0000 3.0000 0.0321 0.0098 0.0319 0.0102 0.0316 0.0107 0.0314 0.0111 0.0312 0.0116 0.0309 0.0120 0.0307 0.0125 0.0304 0.0129 0.0302 0.0134 0.0300 0.0139 0.0297 0.0143 0.0295 0.0148 0.0292 0.0153 0.0290 0.0158 0.0288 0.0162 0.0285 0.0167 0.0283 0.0172 0.0281 0.0177 0.0278 0.0182 0.0276 0.0187 0.0273 0.0192 0.0271 0.0197 0.0269 0.0203 0.0266 0.0208 0.0264 0.0213 0.0261 0.0219 0.0259 0.0224 0.0257 0.0230 0.0254 0.0235 0.0252 0.0241 0.0250 0.0246 0.0247 0.0252 0.0245 0.0258 0.0242 0.0263 0.0240 0.0269 0.0238 0.0275 0.0235 0.0281 0.0233 0.0287 0.0230 0.0293 0.0228 0.0299 0.0226 0.0305 0.0223 0.0311 0.0221 0.0317 0.0219 0.0323 0.0216 0.0329 0.0214 0.0335 0.0211 0.0341 0.0209 0.0347 0.0207 0.0347 Landscape Swale Hydraulic Table 0.0039 0.0040 0.0042 0.0043 0.0043 0.0044 0.0045 0.0046 0.0047 0.0048 0.0049 0.0050 0.0051 0.0051 0.0052 0.0053 0.0054 0.0055 0.0055 0.0056 0.0057 0.0058 0.0058 0.0059 0.0060 0.0061 0.0061 0.0062 0.0063 0.0063 0.0064 0.0066 0.0066 0.0067 0.0068 0.0068 0.0069 0.0069 0.0070 0.0071 0.0071 0.0072 0.0072 0.0073 0.0073 0.0074 0.0075 0.0075 0.0075 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 Stage(ft)Area(ac)Volume(ac-ft)Discharge(cfs)To Amended(cfs)lnfilt(cfs) 3.0000 0.0393 0.0347 0.0000 0.0500 0.0000 3.0385 0.0395 0.0363 0.0000 0.0500 0.0000 3.0769 0.0397 0.0378 0.0000 0.0509 0.0000 3.1154 0.0400 0.0393 0.0000 0.0519 0.0000 3.1538 0.0402 0.0409 0.0000 0.0528 0.0000 3.1923 0.0404 0.0424 0.0000 0.0538 0.0000 REC crnlER 3/3/2015 3 33:08 PM P2,ge 13 3.2308 0.0407 0.0440 0.0000 0.0547 0.0000 3.2692 0.0409 0.0455 0.0000 0.0557 0.0000 3.3077 0.0412 0.0471 0.0000 0.0566 0.0000 3.3462 0.0414 0.0487 0.0200 0.0575 0.0000 3.3846 0.0416 0.0503 0.1243 0.0585 0.0000 3.4231 0.0419 0.0519 0.2766 0.0594 0.0000 3.4615 0.0421 0.0535 0.4646 0.0604 0.0000 3.5000 0.0424 0.0552 0.6826 0.0613 0.0000 REC CENTER 3/3/2015 3 33 08 PM Page 14 Surface IMP-1 Element Flows To: Outlet 1 REC CENTER Outlet 2 IMP-1 3/3/2015 3:33:08 PM Page 15 IMP-2 Bottom Length: Bottom Width: Material thickness of first layer: Material type for first layer: Material thickness of second layer: Material type for second layer: Material thickness of third layer: Material type for third layer: Underdrain used Underdrain Diameter (ft): Orifice Diameter (in): Offset (in): Flow Through Underdrain (ac-ft): Total Outflow (ac-ft): Percent Through Underdrain: Discharge Structure Riser Height: 0.33 ft. Riser Diameter: 12 in. Element Flows To: Outlet 1 Outlet 2 Landscape Swale Hydraulic Table 62.50 ft. 10.00 ft. 2 Sandy loam 1 GRAVEL 0 GRAVEL 0.5 0.5 0 4.446 4.515 98.46 Stage(ft) 0.0000 0.0385 0.0769 0.1154 0.1538 0.1923 0.2308 0.2692 0.3077 0.3462 0.3846 0.4231 0.4615 0.5000 0.5385 0.5769 0.6154 0.6538 0.6923 0.7308 0.7692 0.8077 0.8462 0.8846 0.9231 0.9615 1.0000 1.0385 1.0769 1.1154 1.1538 Area(ac) 0.0402 0.0402 0.0398 0.0395 0.0392 0.0389 0.0385 0.0382 0.0379 0.0375 0.0372 0.0369 0.0365 0.0362 0.0359 0.0355 0.0352 0.0349 0.0345 0.0342 0.0339 0.0336 0.0332 0.0329 0.0326 0.0322 0.0319 0.0316 0.0312 0.0309 0.0306 Volume(ac-ft) 0.0000 Discharge(cfs) lnfilt(cfs) 0.0000 0.0000 0.0001 0.0000 0.0000 0.0002 0.0000 0.0000 0.0003 0.0000 0.0000 0.0005 0.0000 0.0000 0.0006 0.0000 0.0000 0.0007 0.0000 0.0000 0.0008 0.0000 0.0000 0.0010 0.0000 0.0000 0.0011 0.0000 0.0000 0.0012 0.0006 0.0000 0.0014 0.0007 0.0000 0.0015 0.0008 0.0000 0.0017 0.0009 0.0000 0.0018 0.0010 0.0000 0.0020 0.0013 0.0000 0.0021 0.0014 0.0000 0.0024 0.0014 0.0000 0.0027 0.0017 0.0000 0.0030 0.0019 0.0000 0.0034 0.0021 0.0000 0.0037 0.0021 0.0000 0.0040 0.0023 0.0000 0.0044 0.0025 0.0000 0.0047 0.0027 0.0000 0.0050 0.0028 0.0000 0.0054 0.0030 0.0000 0.0058 0.0031 0.0000 0.0061 0.0032 0.0000 0.0065 0.0034 0.0000 0.0069 0.0035 0.0000 REC CENTER 3/3/2015 3:33:08 PM Page 16 1.1923 1.2308 1.2692 1.3077 1.3462 1.3846 1.4231 1.4615 1.5000 1.5385 1.5769 1.6154 1.6538 1.6923 1.7308 1.7692 1.8077 1.8462 1.8846 1.9231 1.9615 2.0000 2.0385 2.0769 2.1154 2.1538 2.1923 2.2308 2.2692 2.3077 2.3462 2.3846 2.4231 2.4615 2.5000 2.5385 2.5769 2.6154 2.6538 2.6923 2.7308 2.7692 2.8077 2.8462 2.8846 2.9231 2.9615 3.0000 3.0000 0.0302 0.0072 0.0299 0.0076 0.0296 0.0080 0.0292 0.0084 0.0289 0.0088 0.0286 0.0092 0.0283 0.0096 0.0279 0.0100 0.0276 0.0104 0.0273 0.0109 0.0269 0.0113 0.0266 0.0117 0.0263 0.0122 0.0259 0.0126 0.0256 0.0131 0.0253 0.0135 0.0249 0.0140 0.0246 0.0144 0.0243 0.0149 0.0240 0.0154 0.0236 0.0159 0.0233 0.0164 0.0230 0.0169 0.0226 0.0174 0.0223 0.0179 0.0220 0.0184 0.0216 0.0190 0.0213 0.0195 0.0210 0.0200 0.0206 0.0206 0.0203 0.0211 0.0200 0.0217 0.0196 0.0222 0.0193 0.0228 0.0190 0.0234 0.0187 0.0239 0.0183 0.0245 0.0180 0.0251 0.0177 0.0257 0.0173 0.0263 0.0170 0.0269 0.0167 0.0275 0.0163 0.0281 0.0160 0.0287 0.0157 0.0294 0.0153 0.0300 0.0150 0.0306 0.0147 0.0313 0.0143 0.0313 Landscape Swale Hydraulic Table 0.0036 0.0037 0.0038 0.0039 0.0040 0.0042 0.0043 0.0043 0.0044 0.0045 0.0046 0.0047 0.0048 0.0049 0.0050 0.0051 0.0051 0.0052 0.0053 0.0054 0.0055 0.0055 0.0056 0.0057 0.0058 0.0058 0.0059 0.0060 0.0061 0.0061 0.0062 0.0063 0.0063 0.0064 0.0066 0.0066 0.0067 0.0068 0.0068 0.0069 0.0069 0.0070 0.0071 0.0071 0.0072 0.0072 0.0073 0.0073 0.0073 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 Stage(ft)Area(ac)Volume(ac-ft)Discharge(cfs)To Amended(cfs)lnfilt(cfs) 3.0000 0.0402 0.0313 0.0000 0.0347 0.0000 3.0385 0.0405 0.0328 0.0000 0.0347 0.0000 3.0769 0.0408 0.0344 0.0000 0.0354 0.0000 3.1154 0.0412 0.0359 0.0000 0.0360 0.0000 3.1538 0.0415 0.0375 0.0000 0.0367 0.0000 3.1923 0.0418 0.0391 0.0000 0.0373 0.0000 REC CE::f'nER 3/3/2015 3 :noB PM f-'3<.ie 17 3.2308 0.0422 0.0408 0.0000 0.0380 0.0000 3.2692 0.0425 0.0424 0.0000 0.0386 0.0000 3.3077 0.0428 0.0440 0.0000 0.0393 0.0000 3.3462 0.0432 0.0457 0.0200 0.0400 0.0000 3.3846 0.0435 0.0473 0.1243 0.0406 0.0000 3.4231 0.0438 0.0490 0.2766 0.0413 0.0000 3.4615 0.0441 0.0507 0.4646 0.0419 0.0000 3.5000 0.0445 0.0524 0.6826 0.0426 0.0000 REC CENTER 3/3/2015 3 33 08 PM Page 18 Surface IMP-2 Element Flows To: Outlet 1 REC CENTER Outlet 2 IMP-2 3/3/2015 3:33:08 PM Page 19 IMP-3 Bottom Length: Bottom Width: Material thickness of first layer: Material type for first layer: Material thickness of second layer: Material type for second layer: Material thickness of third layer: Material type for third layer: Underdrain used Underdrain Diameter (ft): Orifice Diameter (in): Offset (in): Flow Through Underdrain (ac-ft): Total Outflow (ac-ft): Percent Through Underdrain: Discharge Structure Riser Height: 0.33 ft. Riser Diameter: 12 in. Element Flows To: Outlet 1 Outlet 2 Landscape Swale Hydraulic Table 88.00 ft. 10.00 ft. 2 Sandy loam 1 GRAVEL 0 GRAVEL 0.5 0.5 0 4.449 4.463 99.69 Stage(ft) 0.0000 0.0385 0.0769 0.1154 0.1538 0.1923 0.2308 0.2692 0.3077 0.3462 0.3846 0.4231 0.4615 0.5000 0.5385 0.5769 0.6154 0.6538 0.6923 0.7308 0.7692 0.8077 0.8462 0.8846 0.9231 0.9615 1.0000 1.0385 1.0769 1.1154 1.1538 Area(ac) 0.0566 0.0566 0.0561 0.0556 0.0552 0.0547 0.0542 0.0538 0.0533 0.0528 0.0524 0.0519 0.0514 0.0510 0.0505 0.0500 0.0496 0.0491 0.0486 0.0482 0.0477 0.0472 0.0468 0.0463 0.0458 0.0454 0.0449 0.0444 0.0440 0.0435 0.0430 Volume(ac-ft) 0.0000 Discharge(cfs) lnfilt(cfs) 0.0000 0.0000 0.0002 0.0000 0.0000 0.0003 0.0000 0.0000 0.0005 0.0000 0.0000 0.0007 0.0000 0.0000 0.0008 0.0000 0.0000 0.0010 0.0000 0.0000 0.0012 0.0000 0.0000 0.0014 0.0000 0.0000 0.0016 0.0000 0.0000 0.0017 0.0009 0.0000 0.0019 0.0010 0.0000 0.0021 0.0010 0.0000 0.0023 0.0013 0.0000 0.0025 0.0014 0.0000 0.0027 0.0017 0.0000 0.0030 0.0017 0.0000 0.0032 0.0019 0.0000 0.0034 0.0021 0.0000 0.0036 0.0023 0.0000 0.0038 0.0025 0.0000 0.0041 0.0027 0.0000 0.0043 0.0028 0.0000 0.0048 0.0030 0.0000 0.0053 0.0031 0.0000 0.0058 0.0032 0.0000 0.0062 0.0034 0.0000 0.0068 0.0035 0.0000 0.0073 0.0036 0.0000 0.0078 0.0037 0.0000 0.0083 0.0038 0.0000 REC CENTER 3/3/2015 3:33:08 PM Page 20 1.1923 1.2308 1.2692 1.3077 1.3462 1.3846 1.4231 1.4615 1.5000 1.5385 1.5769 1.6154 1.6538 1.6923 1.7308 1.7692 1.8077 1.8462 1.8846 1.9231 1.9615 2.0000 2.0385 2.0769 2.1154 2.1538 2.1923 2.2308 2.2692 2.3077 2.3462 2.3846 2.4231 2.4615 2.5000 2.5385 2.5769 2.6154 2.6538 2.6923 2.7308 2.7692 2.8077 2.8462 2.8846 2.9231 2.9615 3.0000 3.0000 0.0426 0.0088 0.0421 0.0094 0.0416 0.0099 0.0412 0.0105 0.0407 0.0110 0.0402 0.0116 0.0398 0.0122 0.0393 0.0128 0.0389 0.0134 0.0384 0.0140 0.0379 0.0146 0.0375 0.0152 0.0370 0.0158 0.0365 0.0164 0.0361 0.0170 0.0356 0.0177 0.0351 0.0183 0.0347 0.0190 0.0342 0.0197 0.0337 0.0203 0.0333 0.0210 0.0328 0.0217 0.0323 0.0224 0.0319 0.0231 0.0314 0.0239 0.0309 0.0246 0.0305 0.0253 0.0300 0.0261 0.0295 0.0269 0.0291 0.0276 0.0286 0.0284 0.0281 0.0292 0.0277 0.0300 0.0272 0.0308 0.0267 0.0316 0.0263 0.0324 0.0258 0.0332 0.0253 0.0340 0.0249 0.0348 0.0244 0.0357 0.0239 0.0365 0.0235 0.0374 0.0230 0.0382 0.0225 0.0391 0.0221 0.0400 0.0216 0.0409 0.0211 0.0418 0.0207 0.0427 0.0202 0.0427 Landscape Swale Hydraulic Table 0.0039 0.0040 0.0042 0.0043 0.0043 0.0044 0.0045 0.0046 0.0047 0.0048 0.0049 0.0050 0.0051 0.0051 0.0052 0.0053 0.0054 0.0055 0.0055 0.0056 0.0057 0.0058 0.0058 0.0059 0.0060 0.0061 0.0061 0.0062 0.0063 0.0063 0.0064 0.0066 0.0066 0.0067 0.0068 0.0068 0.0069 0.0069 0.0070 0.0071 0.0071 0.0072 0.0072 0.0073 0.0073 0.0074 0.0075 0.0075 0.0075 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 Stage(ft)Area(ac)Volume(ac-ft)Discharge(cfs)To Amended(cfs)lnfilt(cfs) 3.0000 0.0566 0.0427 0.0000 0.0489 0.0000 3.0385 0.0570 0.0448 0.0000 0.0489 0.0000 3.0769 0.0575 0.0470 0.0000 0.0498 0.0000 3.1154 0.0580 0.0493 0.0000 0.0507 0.0000 3.1538 0.0584 0.0515 0.0000 0.0516 0.0000 3.1923 0.0589 0.0538 0.0000 0.0526 0.0000 f,:EC CENTEH 3;3;2015 3 :nos PM Page 21 3.2308 0.0594 0.0560 0.0000 0.0535 0.0000 3.2692 0.0598 0.0583 0.0000 0.0544 0.0000 3.3077 0.0603 0.0606 0.0000 0.0553 0.0000 3.3462 0.0608 0.0630 0.0200 0.0563 0.0000 3.3846 0.0612 0.0653 0.1243 0.0572 0.0000 3.4231 0.0617 0.0677 0.2766 0.0581 0.0000 3.4615 0.0622 0.0701 0.4646 0.0590 0.0000 3.5000 0.0626 0.0725 0.6826 0.0599 0.0000 F~EC crnTER 3;3;201 s 3 :noe PM Page 22 Surface IMP-3 Element Flows To: Outlet 1 REC CENTER Outlet 2 IMP-3 3/3/2015 3:33:08 PM Page 23 I I I I I I I I I I Analysis Results POC 1 .. ... . . - + " .. . .. l<E-3 l<E-2 1<E·1 10 100 ···~------------f- P•r"Qolll.n t: "'T1m • ~-ding u t J I 10 Z0 XI IO ~ to IO II W ti •.t + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area: 1.2 Total Impervious Area: 0 Mitigated Landuse Totals for POC #1 Total Pervious Area: 0.597 Total Impervious Area: 0.582386 Flow Frequency Method : Cunnane Flow Frequency Return Periods for Predeveloped . POC #1 Return Period Flow(cfs) 2 year 0.272398 5 year 0.523598 10 year 0.686276 25 year 0. 753739 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0.021064 5 year 0.047115 10 year 0.069115 25 year 0.150863 REC CENTER 3/3/2015 3:33:08 PM Page 24 Duration Flows The Facility PASSED Flow(cfs) Predev Mit Percentage Pass/Fail 0.0272 399 60 15 Pass 0.0339 354 38 10 Pass 0.0406 318 24 7 Pass 0.0472 286 16 5 Pass 0.0539 253 11 4 Pass 0.0605 235 10 4 Pass 0.0672 212 8 3 Pass 0.0738 197 5 2 Pass 0.0805 181 4 2 Pass 0.0872 174 4 2 Pass 0.0938 165 4 2 Pass 0.1005 157 4 2 Pass 0.1071 153 4 2 Pass 0.1138 149 4 2 Pass 0.1204 143 4 2 Pass 0.1271 135 3 2 Pass 0.1338 125 3 2 Pass 0.1404 111 3 2 Pass 0.1471 106 3 2 Pass 0.1537 100 3 3 Pass 0.1604 97 2 2 Pass 0.1670 92 2 2 Pass 0.1737 87 2 2 Pass 0.1803 80 2 2 Pass 0.1870 75 1 1 Pass 0.1937 75 1 1 Pass 0.2003 71 1 1 Pass 0.2070 68 1 1 Pass 0.2136 64 0 0 Pass 0.2203 59 0 0 Pass 0.2269 56 0 0 Pass 0.2336 52 0 0 Pass 0.2403 51 0 0 Pass 0.2469 48 0 0 Pass 0.2536 45 0 0 Pass 0.2602 42 0 0 Pass 0.2669 41 0 0 Pass 0.2735 36 0 0 Pass 0.2802 33 0 0 Pass 0.2869 31 0 0 Pass 0.2935 29 0 0 Pass 0.3002 28 0 0 Pass 0.3068 27 0 0 Pass 0.3135 24 0 0 Pass 0.3201 23 0 0 Pass 0.3268 23 0 0 Pass 0.3335 22 0 0 Pass 0.3401 22 0 0 Pass 0.3468 21 0 0 Pass 0.3534 21 0 0 Pass 0.3601 20 0 0 Pass 0.3667 19 0 0 Pass 0.3734 18 0 0 Pass REC CENTER 3/3/2015 3 33:22 PM Page 25 0.3801 16 0 0 Pass 0.3867 16 0 0 Pass 0.3934 16 0 0 Pass 0.4000 16 0 0 Pass 0.4067 15 0 0 Pass 0.4133 15 0 0 Pass 0.4200 15 0 0 Pass 0.4267 15 0 0 Pass 0.4333 15 0 0 Pass 0.4400 15 0 0 Pass 0.4466 15 0 0 Pass 0.4533 15 0 0 Pass 0.4599 14 0 0 Pass 0.4666 14 0 0 Pass 0.4733 14 0 0 Pass 0.4799 13 0 0 Pass 0.4866 12 0 0 Pass 0.4932 12 0 0 Pass 0.4999 11 0 0 Pass 0.5065 10 0 0 Pass 0.5132 9 0 0 Pass 0.5199 9 0 0 Pass 0.5265 9 0 0 Pass 0.5332 9 0 0 Pass 0.5398 8 0 0 Pass 0.5465 8 0 0 Pass 0.5531 8 0 0 Pass 0.5598 8 0 0 Pass 0.5665 7 0 0 Pass 0.5731 7 0 0 Pass 0.5798 7 0 0 Pass 0.5864 6 0 0 Pass 0.5931 6 0 0 Pass 0.5997 6 0 0 Pass 0.6064 6 0 0 Pass 0.6130 6 0 0 Pass 0.6197 5 0 0 Pass 0.6264 5 0 0 Pass 0.6330 5 0 0 Pass 0.6397 5 0 0 Pass 0.6463 5 0 0 Pass 0.6530 5 0 0 Pass 0.6596 5 0 0 Pass 0.6663 5 0 0 Pass 0.6730 5 0 0 Pass 0.6796 5 0 0 Pass 0.6863 4 0 0 Pass REC CE:~HER 3/3/2015 3.33.22 PM Page 26 Water Quality REC CENTER 3/3/2015 3:33:22 PM Page 27 Model Default Modifications Total of O changes have been made. PERLND Changes No PERLND changes have been made. IMPLND Changes No IMPLND changes have been made. REC CENTER 3/3/2015 3:33:22 PM Page 28 I I I I I Appendix Predeveloped Schematic 1ST 1.20ac REC CENTER NG ! 3/3/2015 3:33:22 PM Page 29 I I I Mitigated Schematic REC CENTER 3/3/2015 3:33:23 PM Page 30 BMP FACT SHEETS Robertson Ranch Recreation Center Michael Baker Priority Development Project -Storm Water Management Plan INTERNATIONAL BIO RETENTION AREAS SECTION 4: LID DESIGN GUIDE ,, Biorctcntion facility confihrure<l for treatment-only rcyuircmcnts. Hiorctcntion facilities can rcctant-,rular, linear, or nearly any shape. Bioretention detains runoff in a surface reservoir, filters it through plant roots and a biologically active soil mix, and then infiltrates it into the ground. \X'here native soils are less permeable, an underdrain conveys treated runoff to storm drain or surface drainage. Bioretention facilities can be configured in nearly any shape. \'{'hen configured as linear swales, they can convey high flows while percolating and treating lower flows. Bioretention facilities can be configured as in -ground or above- ground planter boxes, with the bottom open to allow infiltration to native soils underneath. If infiltration cannot be allowed, use the sizing factors and criteria for the Flow-Through Planter. ~ CRITERIA For development projects subject only to runoff treatment requirements, the following criteria apply: Parameter Soil mix depth Soil mix minimum percolation rate Soil mix surface area Criterion 18 inches minimum 5 inches per hour minimum sustained (10 inches per hour initial rate recommended) 0.04 times tributary impervious area ( or equivalent) Best Uses • Commercial areas • Residential subdivisions • Industrial developments • Roadways • Parking lots • Fit in setbacks, medians, and other landscaped areas Advantages • Can be any shape • Low maintenance • Can be landscaped Limitations • Require 4% of tributary impervious square footage • Typically requires 3-4 feet of head • Irrigation typically required 85 City of Carlsbad SUSMP-January 14, 2011 Parameter Surface reservoir depth Underdrain ~ DETAILS SECTION 4: LID DESIGN GUIDE Criterion 6 inches minimum; may be sloped to 4 inches where adjoining walkways. Required in Group "C" and "D" soils. Perforated pipe embedded in gravel ("Class 2 permeable" recommended), connected to storm drain or other accepted discharge point. Plan. On the surface, a bioretention facility should be one level, shallow basin-or a series of basins. As runoff enters each basin, it should flood and fill throughout before runoff overflows to the outlet or to the next downstream basin. This will help prevent movement of surface mulch and soil mix. Use check dams for linear bioretcntion facilities (swales) on a slope. In a linear swale, check dams should be placed so that the lip of each dam is at least as high as the toe of the next upstream dam. A similar principle applies to bioretention facilities built as terraced roadway shoulders. Inlets. Paved areas draining to the facility should be graded, and inlets should be placed, so that runoff remains as sheet flow or as dispersed as possible. Curb cuts should be wide (12" is recommended) to avoid clogging with leaves or debris. Allow for a minimum reveal of 4"-6" between the inlet and soil mix elevations to ensure turf or mulch buildup does not block the inlet. In addition, place an apron of stone or concrete, a foot square or larger, inside each inlet to prevent vegetation from growing up and blocking the inlet. 86 City of Carlsbad SUSMP-January 14, 2011 SECTION 4: LID DESIGN GUIDE Underdrains. No underdrain is required where native soils beneath the facility are Hydrologic Soil Group A or B. For treatment-only facilities where native soils are Group C or D, a perforated pipe must be bedded in the gravel layer and must terminate at a storm drain or other approved discharge point. Outlets. In treatment-only facilities, outlets must be set high enough to ensure the surface reservoir fills and the entire surface area of soil mix is flooded before the outlet elevation is reached. In swales, this can be achieved with appropriately placed check dams. The outlet should be designed to exclude floating mulch and debris. Vaults, utility boxes and light standards. It is best to locate utilities outside the bioretention facility-in adjacent walkways or in a separate area set aside for this purpose. If utility structures are to be placed within the facility, the locations should be anticipated and adjustments made to ensure the minimum bioretention surface area and volumes are achieved. Leaving the final locations to each individual utility can produce a haphazard, unaesthetic appearance and make the bioretention facility more difficult to maintain. Emergency overflow. The site grading ( construction) plan shall include details that demonstrate the bioretention basin can handle larger (up to 100-year) storm events and address potential clogging of the overflow and route emergency overflows safely. Trees. Bioretention areas can accommodate small or large trees. There is no need to subtract the area taken up by roots from the effective area of the facility. Extensive tree roots maintain soil permeability and help retain runoff. Normal maintenance of a bioretention facility should not affect tree lifespan. The bioretention facility can be integrated with a tree pit of the required depth and filled with structural soil. If a root barrier is used, it can be located to allow tree roots to spread throughout the bioretention facility while protecting adjacent pavement. Locations and planting elevations should be selected to avoid blocking the facility's inlets and outlets. 1--~,-.,..~ • ---------------..li,..-- i' '~'~i=1 " lt---..,...--:-+--......,.-..,.---n ' . l 18" I Rioretention facility configured as a tree well. '!be root barrier is optional. SIDEWALK 88 City of Carlsbad SUSMP-January 14, 2011 I I I I I I I I I I I I SECTION 4: LID DESIGN GUIDE ~ APPLICATIONS Multi-purpose landscaped areas. Bioretention facilities are easily adapted to serve multiple purposes. The loamy sand soil mix will support turf or a plant palette suitable to the location and a well-drained soil. Example landscape treatments: • Lawn with sloped transition to adjacent landscaping . • Swale in setback area • Swale in parking median • Lawn with hardscaped edge treatment • Decorative garden with formal or informal plantings • Traffic island with low-maintenance landscaping • Raised planter with seating • Bioretention on a terraced slope Bioretcntion facility configured as a recessed decorative lawn with hardscaped edge. 89 '• ~ ·-·· . ...... ,~ -- ¥)" 7 " ! Bioretcntion facility configured and planted as a lawn/ play area City of Carlsbad SUSMP-January 14, 2011 SECTION 4: LID DESIGN GUIDE Residential subdivisions. Some subdivisions are designed to drain roofs and driveways to the streets (in the conventional manner) and then drain the streets to bioretention areas, with one bioretention area for each 1 to 6 lots, depending on subdivision layout and topography. Bioretention areas may be placed on separate, jointly-owned parcel(s). g;=.---- l]i (]! IJ I 1J1 Biorctention facility receiving drainage from individual lots and the street in a residential sulxfo·ision. Sloped sites. Bioretention facilities must be constructed as a basin, or series of basins, with the circumference of each basin set level. It may be necessary to add curbs or low retaining walls. R.,NOl'f 10 Pv.,,rm:l ARI),--- Biorctcntion facility configured as a parking median. Note use of bollards in place of curbs, eliminating the need for curb cuts. 90 City of Carlsbad SUSMP-January 14, 2011 SECTION 4: LID DESIGN GUIDE Design Checklist for Bioretention D Volume or depth of surface reservoir meets or exceeds minimum. D 18" depth "loamy sand" soil mix with minimum long-term percolation rate of 5"/hour. D Area of soil mix meets or exceeds minimum. D Perforated pipe underdrain bedded in "Class 2 perm" with connection and sufficient head to storm drain or discharge point ( except in "A" or "B" soils). D No filter fabric. D Underdrain has a clean-out port consisting of a vertical, rigid, non-perforated PVC pipe, with a minimum diameter of 6 inches and a watertight cap. D Location and footprint of facility are shown on site plan and landscaping plan. D Bioretention area is designed as a basin (level edges) or a series of basins, and grading plan is consistent with these elevations. If facility is designed as a swale, check dams are set so the lip of each dam is at least as high as the toe of the next upstream dam. D Inlets are 12" wide, have 4"-6" reveal and an apron or other provision to prevent blockage when vegetation grows in, and energy dissipation as needed. D Overflow connected to a downstream storm drain or approved discharge point. D Emergency spillage will be safely conveyed overland. D Plantings are suitable to the climate and a well-drained soil. D Irrigation system with connection to water supply. D Vaults, utility boxes, and light standards are located outside the minimum soil mix surface area. D When excavating, avoid smearing of the soils on bottom and side slopes. l'vlinimize compaction of nati,-e soils and "rip" soils if clayey and/ or compacted. Protect the area from construction site runoff. 91 City of Carlsbad SUSMP-January 14, 2011 SECTION 4: LID DESIGN GUIDE TOP OF BASIN EMERGENCY SPILLWAY OUTFLOW NOTE BASIN OUTLET (SEE DETAIL) PERFORATED PIPE (UNOERORAIN) SURFACE AREA (NOTE 1) PLAN VIEW NOT TO SCALE STORAGE 1B" SPECIFlEO PLANTING MIX 1. SURFACE AREA LIMIT DETERMINED BY EXTENT OF SPECIFIED PLANTING MIX, WHICH IS GOVERNED BY THE OUTLET SPILL ELEVATION. FOR REQUIRED SURFACE AREA REFER TO THE FACTORS AND EQUATIONS IN THE STORMY/ATER C J GUIDEBOOK. 2. V2 STORAGE ACCOMPLISHED WITH INFILTRATION ARCHES, PERFORATED PIPES. CL.ASS 2 PERM OR OlHER AT THE DESIGNERS DISCRETION. Bioretention Facility TOP OF BASIN FOREBAY /CLEANOUT 92 City of Carlsbad SUSMP-January 14, 2011 PERFORATED UNOERORAJN Fl.ANGE .!t ORIFICE PLATE CONNECTION (SEE NOTE 1) CATCH BASIN SECTION 4: LID DESIGN GUIDE L- CLOSED MESH GRATE (GEN. NOTES 4 THRU 7) PLAN N.T.S. CLOSED MESH GRATE (GEN. NOTES 4 THRU 7) ORIFICE PLATE SEE DETAIL THIS SHEET (GEN. NOTE 3) OUTFALL PIP[ (GEN. NOTE 1) PERFORATED UNDERDRAIN SECTION N.T.S. NOTE 1. ORIFICE PLATE .!t FLANGE CONNECTION TO CONCRffi SHALL BE FITTED WITH ORIFICE PLATE, MIN SQUARE DIMENSIONS 1 .O FT GREATER THAN PIPE OIA. HOT-DIP GALVANIZED PLATE AFTER HOLES HAVE SEEN DRILLED j"MAX 6" (1YP) .. (1YP) ORIFICE DIAMffiR (DIA) SIZED PER DESIGN CRITERIA 30 DUROMffiR NEOPRENE RING. i-OlA HOLE (m') FLOW CONTROL ORIFICE PLATE Bioretention Facility Outlet Detail - A 93 City of Carlsbad SUSMP-January 14, 2011 PERVIOUS UNIT PAYERS I I ) Eco Dublin™ Environmental Collection Beauty, funct1onal1ty and quality are hallmarks of the Belgard' Commercial brand, and our Environmental Collection of permeable pavers 1s no exception. Belgard permeable pavers combine the best of Belgard with 1nnovat1ve stormwater management for a superior product line that provides sustainable solutions and aesthetically appealing designs. • ADA COMPLIANT II LT. VEHICVLAR-BOMM ~ MECHANICAL INSTALLATION ~ I I I Benefits of Belgard® Permeable Paving Stone Systems • On the US Env1runmental Protection Agency s (EPA) me1u fo1 st ructural Low lrnµact Development (LID) BMPs • Can contr bute toward several LEED NC-2009 points • Reduces star mwater runoff by up lo 100% • Can he used to achieve total max mum daily load (TMDL) l1m1ts for a ra0ge of pollutants • Cer t1f1ed SRI coloi s r ejuce heat island effect • Can re J,1ce or eliminate the need for trad1t1onal drainage and dPtent on r equ11 ements. sav•ng spa~e and money • Can be oes19ned o accommodate all natrve soil types • 50-year design life based on proven field performance SAMPLE PICP SYSTEM CROSS SECTION Joinl/VooF• lyp.8.89or 8•dPermeab6e 9_,,epte PAl/£RS (o,srnla,) Beddire eoun. 1l/2kl2''fyp.8,ar ... o,,.,,-Grlded a. .. 4"f>"P,.5711one Sub-Base M111.8'f)ip.No.2 sti:ine (or•llr> Underd,ain l~w,tr,pert>al:•nOno -.httr,toondti11.n,,,notr.qund ..,,~..,""ltot!Offlf:"' I I I l-----Geosynthetics on bottom and sides of open 1Uaded base (Ofll:OCll'IIII saot-tile fO!' .... ~ P*"•• •hltntoon-..i..~..,,.,lor l'IO -.tMlrtl-°"""') The 8\laleblty °' spec:lle ~· w11 often vary fn::m region to region. In C6SM wheN it becomes neoesMry to substitute• limler tlze. 'f04JI pn:,t«:t engineer~..,, be ~ed. Eco Dublin™ Smart-looking style meets smart science. The classic look of cut stone and contemporary materials technology combine in Eco Dubl nT•1 the latest addition to Belgard's Environmental Series of permeable pavers. 3 7/16" X 6 7/8" X 3 1/8" (87.78mm x 174.57mm x 80mm) 6 7/8" X 6 7/8" X 3 1/8" (174.57mm x 174.57mm x 80mm) 3 7/16" X 101/4" X 31/8" (174.57mm x 261.35mm x 80mm) Shapes (All three shapes come in each bundle.) Mechanical Installation Laying Pattern