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HomeMy WebLinkAboutMS 04-18; EUCALYPTUS LANE; STORM WATER MANAGEMENT PLAN AND DRAINAGE STUDY; 2006-04-01L2I .6 ~IESSIO z 60223 Uj CC EXP. 6/30106 ) )) STORM WATER MANAGEMENT PLAN AND DRAINAGE STUDY FOR EUCALYPTUS LANE MS 04-18 Prepared: April 2006 J.N. 061163-01 Prepared for: Family Real Estate Enterprises, LLC 560 N. Coast Highway 101, Suite 1 Encinitas, CA 92024 Prepared by: O'Day Consultants, Inc. 2710 Loker Avenue West, Suite 100 Carlsbad, CA 92010 KeA W. Hansen, RCE 60223, Exp. 6/30/06 J TABLE OF CONTENTS Section 1.0 - Vicinity Map Section 2.0 - Project Description Section 3.0 - Site. Map Section 4.0 - Pollutants and Conditions of Concern Pollutants of Concern Name and Number of Carlsbad Watershed Hydrological Unit Impaired Water Bodies Downstream of the Project and Impairment San Diego Region Hydrologic Units, Areas, and Subareas (Fig. 1-2) 2002 California 303 (d) List and TMDL Priority Schedule (list) Storm Water Requirements Applicability Checklist (Appendix A) . Construction Site Priority (Part D) Standard Development Project & Priority Project Storm Water BUT Requirements Matrix (Table 1) Conditions of Concern Section 5.0 - Site Design BMPs Section 6.0 - Source Control BMPs Fact & Maintenance Requirement Sheets for: . Efficient Irrigation (SD-12) Storm Drain Signage (SD-13) Spill Prevention, Control & Cleanup (SC- 11) Landscape Maintenance (SC-73) Section 7.0 - Structural Treatment BMPs Anticipated and Potential Pollutants Generated by Land Use Type (Table 2) Numeric Sizing Treatment Standards (Table 3) Structural Treatment Control BUT Selection Matrix (Table 4) Fact Sheets for BMPs - Including Inspection, Maintenance, Costs and Training for: • Multiple System (TC-60) Drainage Inserts with "Bio Clean" Grated Inlets with Hydrocarbon Absorption Booms (MP-52 & Manufacturer's Information) Section 8.0 - Post Construction BMPs Maintenance Cost Responsibilities Section 9.0 - Drainage Study for Eucalyptus Lane MS 04-18 I:\061163\SWMP\cover & toc.doc CITY OF OCEANSIDE HIGHWAY PROJECT - CITY OF VISTA SITE - AMBROSIA CITY OF SAN MARCOS PACIFIC OCEAN CITY OF ENCINITAS VICINITY MAP NO SCALE Section 2.0 Project Description The project is located on the north side of Eucalyptus Lane at the intersection with Crestview Drive in the City of Carlsbad. The assessor's parcel number is 208-040-05. (See Vicinity Map, Section 1.0). The site is a knoll with existing dwelling and a minimal amount of vegetation. The site is directly adjacent to El Camino Real and an existing 150400t wide SDG&E easement along Crestview Drive. The developed condition will be to grade the southerly portion of the knoll to create three (3) building pads. The site will encompass approximately 2.12 acres of the 4.95 acre drainage basin. 1 SHEET 1 OF SHEET 1 K LEGEND B/OSWALE INLET F/L TRA T/ON BASKET 0' 10' 40' 5' 20' 80' SCALE: 1" = 40' S LANE STORM WA TEE MAMA CEMENT PLA N SITE AMP ©2006 O'Day Consultants, Inc. I MOTEL' I ELECTRON/C DATA F/LES ARE FOR REFERENCE I OWL Y AND ARE NOT TO BE USED FOR HORIZONTAL OR VERTICAL SURVEY CONTROL 0 DESIGNED BY: S.K. DRAWN BY: B.B. DATE: APRIL 2006 SCALE: AS SHOWN PROJECT CONSULT A10 N T S MGR.: K.H. JOB NO.: 06-1163 2710 Loker Avenue West Civil Engineering ENGINEER OF WORK: Suite 100 Planning Carlsbad, California 92010 Processing 760-931-7700 Surveying DATE: Fax: 760-931-8680 KEITH W. HANSEN RCE: 60223 :\061163\0663SMWP01.DWC Apr 12, 2006 2:00pm Xrefs: 0663T0P0; 0663p1an; 0663amap; 0663astr; 0663ACRD; TOPO—SHT53 Section 4.0 Pollutants of Concern Based upon the Water Quality Control Plan for the San Diego Basin (9), the site is located in the Hydrologic Unit 904._ and ultimately drains into Agua Hedionda Lagoon. According to the 2002 CWA 303(d) List of Water Quality Limited Segments for the San Diego Basin(9), this watershed is tagged by the San Diego Regional Water Quality Control Board as receiving storm water runoff with high coliform counts (low priority) and sedimentation/siltation (low priority). See the attached Hydrologic Unit Map and List. Conditions of Concern See the hydrology/hydraulic study prepared specifically for this lot (attached in Section 9.0). 2 LEGEND -- DRAINAGE PROVINCE BOUNDARY - HYDROLOGIC UNIT BOUNDARY HYDROLOGIC AREA BOUNDARY HYDROLOGIC SUBAREA BOUNDARY FIGURE 1-2. SAN DIEGO REGION HYDROLOGIC UNITS AREAS, AND SUBAREAS FIGURE 1-2 INTRODUCTION 1 September 8. 1 )94 Storm Water Standards 4/03/03 VI.- RESOURCES & REFERENCES APPENDIX A STORM WATER REQUIREMENTS APPLICABILITY CHECKLIST Complete Sections 1 and 2 of the following checklist to determine your project's permanent .and construction storm water best management practices requirements. This form must be completed and submitted with your permit application. Section 1. Permanent Storm Water BMP Requirements: If any answers to Part A are answered "Yes," your project is subject to the "Pnority Project Permanent Storm Water BMP Requirements," and "Standard Permanent Storm Water BMP Requirements" in Section ill, "Permanent Storm Water BMP Selection Procedure" in the Storm Water Standards manual. If all answers to Part A are "No," and any answers to Part B are "Yes," your project is only subject to the "Standard Permanent Storm Water BMP Requirements". If every question in Part A and B is answered UNOI your project is exempt from permanent storm water requirements. Part A: Determine Priority Project Permanent Storm Water BMP Requirements. Does the project meet the definition of one or more of the priority project categories?* Yes No Detached residential development of 10 or more units Attached residential development of 10 or more units - x Commercial development greater than 100,000 square feet Ic AutOmotive repair shop - Restaurant - x Steep hillside development greater than 5,000 square feet X - Project discharging to receiving waters within Environmentally Sensitive Areas - K Parking lots greater than or equal to 5,000 ft' or with at least 15 parking spaces, and potentially exposed to urban runoff X Streets, roads, highways, and freeways which would create a new paved surface that is 5,000 square feet or greater X * Refer to the definitions section in the Storm Water Standards for expanded definitions of the priority project categories. Limited Exclusion: Trenching and resurfacing work associated with utility projects are not considered priority projects. Parking lots, buildings and other structures associated with utility projects are priority projects if one or more of the criteria in Part A is met. If all answers to Part Aare "No", continue to Part B. 30 Storm Water Standards 4/03/03 Part B: Determine Standard Permanent Storm Water Requirements. Does the project propose: Yes No New impervious areas, such as rooftops, roads, parking lots, driveways, paths and sidewalks? - New pervious landscape areas and irrigation systems? x Permanent structures within 100 feet of any natural water body? Trash storage areas? Liquid or solid material loading and unloading areas? - Vehicle or equipment fueling, washing, or maintenance areas? - Require a General NPDES Permit for Storm Water Discharges Associated with Industrial Activities (Except construction)? Commercial or industrial waste handling or storage, excluding typical office or household waste? - Any grading or ground disturbance during construction? Any new storm drains, or alteration to existing storm drains? To find out if your project is required to obtain an -individual General NPDES Permit for Storm Water Discharges Associated with Industrial Activities, visit the State Water Resources Control Board web site t, www.swrcb.ca.gov/stormwtr/lndustrial.html Section 2. ConstructIon Storm Water BMP Requirements: If the answer to question I of Part C is answered "Yes," your project is subject to Section IV, "Construction Storm Water BMP Performance Standards," and must prepare a Storm Water Pollution Prevention Plan (SWPPP). If the answer to question I is "No," but the answer to any of the remaining questions is "Yes," your project is subject to Section IV, "Construction Storm Water BMP Performance Standards," and must p repare a Water Pollution Control Plan (WPCP). If every q uestion in P art C is answered "No," your project is exempt from any construction storm water BMP requirements. If any of the answers to the questions in Part C are "Yes," complete the construction site prioritization in Part D, below. Part C: Determine Construction Phase Storm Water Reciuirements. Would the project meet any of these criteria during construction? Yes No Is the project subject to California's statewide General NPDES Permit for Storm Water Discharges Associated With Construction Activities? X - Does the project propose grading or soil disturbance? Would storm water or urban runoff have the potential to contact any portion of the construction area, including washing and staging areas? Would the project use any construction materials that could negatively affect water quality if discharged from the site (such as, paints, solvents, concrete, and stucco)? - 31 Storm Water Standards 4/03/03 Part 0: Determine Construction Site Priority In accordance with the Municipal Permit, each construction site with construction storm water BMP requirements must be designated with a priority: high, medium or low. This prioritization must be completed with this form, noted on the plans, and included in the SWPPP or WPCP. Indicate the project's priority in one of the check boxes using the criteria below, and existing and surrounding conditions of the project, the type of activities necessary to complete the construction and any other extenuating circumstances that may pose a threat to water quality. The City reserves the right to adjust the priority of the projects both before and during construction. [Note: The construction priority does NOT change construction BMP requirements that apply to projects; all construction BMP requirements must be identified on a case-by-case basis. The construction priority does affect the frequency of inspections that will be conducted by City staff. See Section IV.1 for more details on construction BMP requirements.] U A) High Priority Projects where the site is 50 acres or more and grading will occur during the rainy season Projects 5 acres or more. 3) Projects 5 acres or more within or directly adjacent to or discharging directly to a coastal lagoon or other receiving water within an environmentally sensitive area Projects, active or inactive, adjacent or tributary to sensitive water bodies tj B) Medium Priority Capital Improvement Projects where grading occurs, however a Storm Water Pollution Prevention Plan (SWPPP) is not required under the State General Construction Permit (i.e., water and sewer replacement projects, intersection and street re-alignments, widening, comfort stations, etc.) Permit projects in the public right-of-way where grading occurs, such as installation of sidewalk, substantial retaining walls, curb and gutter for an entire street frontage, etc. , however SWPPPs are not required. Permit projects on private property where grading permits are required, however, Notice Of Intents (NOls) and SWPPPs are not required. (] C) Low Priority Capital Projects where minimal to no grading occurs, such as signal light and loop installations, street light installations, etc. Permit projects in the public right-of-way where minimal to no grading occurs, such as pedestrian ramps, driveway additions, small retaining walls, etc. Permit projects on private property where grading permits are not required, such as small retaining walls, single-family homes, small tenant improvements, etc. 32 Storm Water Standards 4/03/03 ThIA t Standard Davelonment Prolect & Priority Proiect Storm Water BMP Reaulrements Matrix. BMPs Applicable to Individual - rIody Project çtggdeW$) CO CD 20 U D) 8 C icoc ,co ?: cc 0 a CL 0 . 75 M Site Source . G3 0 > w 0 en U- Treatment Design Control Control BMPsø) BMPs(l) 0 0 0 0) C BMPs() Standard Projects R R 1 0 1 0 1 0 1 0 1 0 1 0 1 0 0 1 0 1 0 0 Priority Projects: Detached Residential Q ® i0 iIIIIII Development V-1.) Attached Residential R R R S Development Commercial Development R R - R R R - R - - - S >100,000 ft2 Automotive Repair Shop R R - R R R R - - R - S Restaurants R R R R S Hillside Development Q >5,000 ft2 _ Parking Lots R _______ r R R(5) - - S Streets, Highways & R R Freeways R = Required; select one or more applicable and appropriate BMPs from the applicable steps in Section 111.2.A-D, or equivalent as identified in Appendix C. 0 = Optional/ or may be required by City staff. As appropriate, applicants are encouraged to incorporate treatment control BMPs and BMPs applicable to individual priority project categories into the project design. City staff may require one or more of these BMPs, where appropriate. S = Select one or more applicable and appropriate treatment control BMPs from Appendix C. Refer to Section 111.2.A. Refer to Section 111.2.13. Priority project categories must apply specific storm water BMP requirements, where applicable. Priority projects are subject to the requirements of all priority project categories that apply. Refer to Section 111.2.0. Applies if the paved area totals >5,000 square feet or with >15 parking spaces and is potentially exposed to urban runoff. Section 5.0 Site Design BMPs See Site Map (in Section 3.0) Impervious areas have been designed to drain into vegetated swales prior to discharge into the storm water conveyance system to the maximum extent practicable. Water quality catch basin and curb inlet inserts are to be installed in structures collecting runoff from pollution generating surfaces (those that are subjected to vehicular traffic) to decrease the amount of pollutants entering the storm drainage system. See Section 7.0 for literature discussing the capabilities of such BMPs. All the slopes and landscape areas will have permanent landscaping consistent with the Carlsbad Landscape Manual. Energy dissipators are to be used at locations where storm water is being discharged at erosive velocities. Section 6.0 Source Control BMPs Hazardous materials with potential to contaminate urban runoff will not be stored on-site. The project will use efficient irrigation systems and landscape design to include rain shut-off devices to prevent irrigation during precipitation, consistent with the Carlsbad Landscape Manual. Irrigation systems will be designed to each landscape area's specific water requirements consistent with the Carlsbad Landscape Manual. (See Fact Sheet SD- 12) Existing hillside areas disturbed by the project development shall be landscaped with deep rooted drought tolerant plant species selected for erosion control, in accordance with Carlsbad Landscape Manual. 4 ( Efficient Irrigation SD-12 Design Objectives 1 Maximize Inflifratlon I Provide Retention 1 Slow Runoff Minimize Impervious land Coverage Prohibit Dumping of Improper Materials Contain Pollutants Collect and Convey Description Irrigation water provided to landscaped areas may result in excess irrigation water being conveyed into stormwater drainage systems. Approach Project plan designs for development and redevelopment should include application methods of irrigation water that minimize runoff of excess Irrigation water into the stormwater conveyance system. Suitable Applications Appropriate applications include residential, commercial and industrial areas planned for development or redevelopment. (Detached residential single-family homes are typically excluded from this requirement.) Design Considerations Designing New Installations The following methods to reduce excessive irrigation runoff should be considered, and incorporated and implemented where determined applicable and feasible by the Permittee: Employ rain-triggered shutoff devices to prevent irrigation after precipitation. Design irrigation systems to each landscape area's specific water requirements. Include design featuring flow reducers or shutoff valves triggered by a pressure drop to control water loss in the event of broken sprinkler heads or lines. . Implement landscape plans consistent with County or City water conservation resolutions, which may include provision of water sensors, programmable irrigation times (for short cycles), etc. VC .i. S Q A :.. jërorn; Stormwater i Quality f Association January 2003 California Stormwater BMP Handbook t nf 2 '50-12 Efficient Irrigation Design timing and application methods of irrigation water to minimize the runoff of excess irrigation water into the storm water drainage system. Group plants with similar water requirements in order to reduce excess irrigation runoff and promote surface filtration, Choose plants with low irrigation requirements (for example, native or drought tolerant species). Consider design features such as: - Using mulches (such as wood chips or bar) in planter areas without ground cover to minimize sediment in runoff - Installing appropriate plant materials for the location, in accordance with amount of sunlight and climate, and use native plant materials where possible and/or as recommended by the landscape architect - Leaving a vegetative barrier along the property boundary and interior watercourses, to act as a pollutant filter, where appropriate and feasible - Choosing plants that minimize or eliminate the use of fertilizer or pesticides to sustain growth Employ other comparable, equally effective methods to reduce irrigation water runoff. Aedeveloping Existing Installations Various jurisdictional stormwater management and mitigation plans (SUSMP, WQMP, etc.) define "redevelopment' in terms of amounts of additional impervious area, increases in gross floor area and/or exterior construction, and land disturbing activities with structural or impervious surfaces. The definition of" redevelopment" must be consulted to determine whether or not the requirements for new development apply to areas intended for redevelopment. If the definition applies, the steps outlined under "designing new installations" above should be followed. Other Resources A Manual for the Standard Urban Stormwater Mitigation Plan (SUSMP), Los Angeles County Department of Public Works, May 2002. Model Standard Urban Storm Water Mitigation Plan (SUSMP) for San Diego County, Port of San Diego, and Cities in San Diego County, February 14, 2002. Model Water Quality Management Plan (WQMP) for County of Orange, Orange County Flood Control District, and the Incorporated Cities of Orange County, Draft February 2003. Ventura Countywide Technical Guidance Manual for Stormwater Quality Control Measures, July 2002. - -- ----.- - 2 o 2 California Stormwater BMP Handbook January 2003 Storm Drain Signage SD-13 Design Objectives Maximize Infiltration Provide Retention Slow Runoff Minimize Impervious Land Coverage / Prohibit Dumping of Improper Materials Contain Pollutants Collect and Convey Description Waste materials dumped into storm drain inlets can have severe impacts on receiving and ground waters Posting notices regarding discharge prohibitions at storm drain inlets can prevent waste dumping. Storm drain signs and stencils are highly visible source controls that are typically placed directly adjacent to storm drain inlets. Approach The stencil or affixed sign contains a brief statement that prohibits dumping of improper materials into the urban runoff conveyance system. Storm drain messages have become a popular method of alerting the public about the effects of and the prohibitions against waste disposal. Suitable Applications Stencils and signs alert the public to the destination of pollutants discharged to the storm drain. Signs are appropriate in residential, commercial, and industrial areas, as well as any other area where contributions or dumping to storm drains is likely. Design Considerations Storm drain message markers or placards are recommended at all storm drain inlets within the boundary of a development project The marker should be placed in clear sight facing toward anyone approaching the inlet from either side. All storm drain inlet locations should be identified on the development site map. Designing New Installations The following methods should be considered for inclusion in the project design and show on project plans: Provide stenciling or labeling of all storm drain inlets and catch basins, constructed or modified, within the project area with prohibitive language. Examples include "NO DUMPING - California Stormwater Quality Association { D13 Storm Drain Signage DRAINS TO OCEAN" and/or other graphical icons to discourage illegal dumping. i Post signs with prohibitive language and/or graphical icons, which prohibit illegal dumping at public access points along channels and creeks within the project area. iote - Some local agencies have approved specific signage and/or storm drain message placards for use. Consult local agency stormwater staff to determine specific requirements for placard ypes and methods of application. Redeveloping Existing Installations Tarious jurisdictional stormwater management and mitigation plans (SUSMP, WQMP, etc.) lefine "redevelopment" in terms of amounts of additional impervious area, increases in gross floor area and/or exterior construction, and land disturbing activities with structural or mpervlous surfaces. If the project meets the definition of "redevelopment", then the requirements stated under" designing new installatione above should be included in all project design plans. Additional Information Maintenance Considerations Legibility of markers and signs should be maintained. If required by the agency with ". jurisdiction over the project, the owner/operator or homeowner's association should enter into a maintenance agreement with the agency or record a deed restriction upon the property title to maintain the legibility of placards or signs. Placement a Signage on top of curbs tends to weather and fade. a Signage on face of curbs tends to be worn by contact with vehicle tires and sweeper brooms. Supplemental Information Examples a Most MS4 programs have storm drain signage programs. Some MS4 programs will provide stencils, or arrange for volunteers to stencil storm drains as part of their outreach program. Other Resources A Manual for the Standard Urban Stormwater Mitigation Plan (SUSMP), Los Angeles County Department of Public Works, May 2002. ft Model Standard Urban Storm Water Mitigation Plan (SUSMP) for San Diego County, Port of San Diego, and Cities in San Diego County, February 14, 2002. Model Water Quality Management Plan (WQMP) for County of Orange, Orange County Flood Control District, and the Incorporated Cities of Orange County, Draft February 2003. Ventura Countywide Technical Guidance Manual for Stormwater Quality Control Measures, July 2002. , ,F 3 California Stormwater i3MP Handbook January 2003 Spill Prevention, Control & Cleanup SC-11 Objectives .Cover contain Educate a ReduceiMlniniize Product Substitution Description Many activities that occur at an industrial or commercial site Targeted Constituents have the potential to cause accidental or illegal spills. Sediment Preparation for accidental or illegal spills, with proper training Nutrients and reporting systems Implemented, can minimize the discharge Trash of pollutants to the environment. Metals / Spills and leaks are one of the largest contributors of stormwater Bacteria pollutants. Spill prevention and control plans are applicable to Oil and Grease any site at which hazardous materials are stored or used. An OT95fliC5 / effective plan should have spill prevention and response procedures that identify potential spill areas, specify material handling procedures, describe spill response procedures, and provide spill dean-up equipment The plan should take steps to identify and characterize potential spills, eliminate and reduce spill potential, respond to spills when they occur in an effort to prevent pollutants from entering the stormwater drainage system, and train personnel to prevent and control future spills. Approach Pollution Prevention Develop procedures to prevent/mitigate spills to storm drain systems. Develop and standardize reporting procedures, containment, storage, and disposal activities, documentation, and follow-up procedures. Develop a Spill Prevention Control and Countermeasure (SPCC) Plan. The plan should include: s A call 'M Stormwater Quality Auodatfon January 2003 California Stormwater BMP Handbook i of 9 Industrial and Commercial www.cabmphandbooks.com SC-11 Spill Prevention, Control & Cleanu - Description of the facility, owner and address, activities and chemicals present - Facility map - Notification and evacuation procedures - Cleanup instructions - Identification of responsible departments - Identify key spill response personnel Recycle, reclaim, or reuse materials whenever possible. This will reduce the amount of process materials that are brought into the fadlity. Suggested Protocols (including equipment needs) Spill Prevention Develop procedures to prevent/mitigate spills to storm drain systems. Develop and standardize reporting procedures, containment, storage, and disposal activities, documentation, and follow-up procedures. a If consistent illegal dumping is observed at the facility- - Post "No Dumping" signs with a phone number for reporting illegal dumping and disposal. Signs should also indicate fines and penalties applicable for illegal dumping. - Landscaping and beautification efforts may also discourage illegal dumping. - Bright lighting and/or entrance barriers may also be needed to discourage illegal dumping. a Store and contain liquid materials in such a manner that if the tank is ruptured, the contents will not discharge, flow, or be washed into the storm drainage system, surface waters, or groundwater. a If the liquid is oil, gas, or other material that separates from and floats on water, install a spill control device (such as a tee section) in the catch basins that collects runoff from the storage tank area. Routine maintenance: - Place drip pans or absorbent materials beneath all mounted taps, and at all potential drip and spill locations during filling and unloading of tanks. Any collected liquids or soiled absorbent materials must be reused/recycled or properly disposed. - Store and maintain appropriate spill cleanup materials in a location known to all near the tank storage area; and ensure that employees are familiar with the site's spill control plan and/or proper spill cleanup procedures. - Sweep and clean the storage area monthly if it is paved, do not hose down the area to a storm drain. 2 of 9 California Stormwater BMP Handbook January 2003 industrial and Commercial www.cabmphandbooks.com Spill Prevention, Control & Cleanup SC-11 - Check tanks (and any containment sumps) daily for leaks and spills. Replace tanks that are leaking, corroded, or otherwise deteriorating with tanks in good condition. Collect all spilled liquids and properly dispose of them. Label all containers according to their contents (e.g., solvent, gasoline). Label hazardous substances regarding the potential hazard (corrosive, radioactive, flammable, explosive, poisonous). Prominently display required labels on transported hazardous and toxic materials (per US DOT regulations). Identify key spill response personnel. Spill Control and Cleanup Activities Follow the Spill Prevention Control and Countermeasure Plan. • Clean up leaks and spills immediately. Place a stockpile of spill cleanup materials where it will be readily accessible (e.g., near storage and maintenance areas). On paved surfaces, clean up spills with as little water as possible. Use a rag for small spills, a damp mop for general cleanup, and absorbent material for larger spills. If the spilled material is hazardous, then the used cleanup materials are also hazardous and must be sent to a certified laundry (rags) or disposed of as hazardous waste. Physical methods for the cleanup of dry chemicals include the use of brooms, shovels, sweepers, or plows. Never hose down or bury dry material spills. Sweep up the material and dispose of properly. Chemical cleanups of material can be achieved with the use of adsorbents, gels, and foams. Use adsorbent materials on small spills rather than hosing down the spill. Remove the adsorbent materials promptly and dispose of properly. For larger spills, a private spill cleanup company or Hazmat team maybe necessary. Reporting Report spills that pose an immediate threat to human health or the environment to the Regional Water Quality Control Board. Federal regulations require that any oil spill into a water body or onto an adjoining shoreline be reported to the National Response Center (NRC) at 800-4-8802 (24 hour). Report spills to local agencies, such as the fire department; they can assist in cleanup. Establish a system for tracking incidents. The system should be designed to identify the following: - Types and quantities (in some cases) of wastes - Patterns in time of occurrence (time of day/night, month, or year) January 2003 California Stormwater BMP Handbook 3 of 9 Industrial and Commercial www.cabmphandbooks.com SC-11 Spill Prevention, Control & Cleanu Mode of dumping (abandoned containers, "midnight dumping" from moving vehicles, direct dumping of materials, accidents/spills) - Responsible parties Training . Educate employees about spill prevention and cleanup. a Well-trained employees can reduce human errors that lead to accidental releases or spills: - The employee should have the tools and knowledge to immediately begin cleaning up a spill should one occur. - Employees should be familiar with the Spill Prevention Control and Countermeasure Plan. Employees should be educated about aboveground storage tank requirements. Employees responsible for aboveground storage tanks and liquid transfers should be thoroughly familiar with the Spill Prevention Control and Countermeasure Plan and the plan should be readily available. a Train employees to recognize and report illegal dumping incidents. Other Considerations (Limitations and Regulations) State regulations exist for facilities with a storage capacity of 10,000 gallons or more of petroleum to prepare a Spill Prevention Control and Countermeasure (SPCC) Plan (Health & Safety Code Chapter 6.67). State regulations also exist for storage of hazardous materials (Health & Safety Code Chapter 6.95), including the preparation of area and business plans for emergency response to the releases or threatened releases. Consider requiring smaller secondary containment area (less than 200 sq. ft.) to be connected to the sanitary sewer, prohibiting any hard connections to the storm drain. Requirements Costa (including capital and operation & maintenance) . Will vary depending on the size of the facility and the necessary controls. Prevention of leaks and spills is inexpensive. Treatment and/or disposal of contaminated soil or water can be quite expensive. Maintenance (including administrative and staffing) This BMP has no major administrative or staffing requirements. However, extra time is needed to properly handle and dispose of spills, which results in increased labor costs. 4 of 9 California Stormwater BMP Handbook January 2003 Industrial and Commercial wwwcabmphandbooks.com Spill Prevention, Control & Cleanup sc11 Supplemental Information Further Detail of the BMP Reporting Record keeping and internal reporting represent good operating practices because they can increase the efficiency of the facility and the effectiveness of BMPs. A good record keeping system helps the facility minimize incident recurrence, correctly respond with appropriate cleanup activities, and comply with legal requirements A record keeping and reporting system should be set up for documenting spills, leaks, and other discharges, including discharges of hazardous substances in reportable quantities.: Incident records describe the quality and quantity of non-stormwater discharges to the storm sewer. These records should contain the Mowing information: . Date and time of the incident . Weather conditions . Duration of the spill/leak/discharge . Cause of the spill/leak/discharge . Response procedures implemented Persons notified Environmental problems associated with the spill/leak/discharge Separate record keeping systems should be established to document housekeeping and preventive maintenance inspections, and training activities. All housekeeping and preventive maintenance inspections should be documented. Inspection documentation should contain the following information: The date and time the inspection was performed Name of the inspector Items inspected Problems noted Corrective action required Date corrective action was taken Other means to document and record inspection results are field notes, timed and dated photographs, videotapes, and drawings and maps. Aboveground Tank Leak and Spill Control Accidental releases of materials from aboveground liquid storage tanks present the potential for contaminating stormwater with many different pollutants. Materials spilled, leaked, or lost from January 2003 California Stormwater BMP Handbook 5 of 9 Industrial and Commercial www.cabmphandbooks.com SC-11 Spill Prevention, Control & Cleanup tanks may accumulate in soils or on impervious surfaces and be carried away by stormwater runoff. The most common causes of unintentional releases are: Installation problems Failure of piping systems (pipes, pumps, flanges, couplings, hoses, and valves) External corrosion and structural failure Spills and overfills due to operator error Leaks during pumping of liquids or gases from truck or rail car to a storage tank or vice versa Storage of reactive, ignitable, or flammable liquids should comply with the Uniform Fire Code and the National Electric Code. Practices listed below should be employed to enhance the code requirements: Tanks should be placed in a designated area. Tanks located in areas where firearms are discharged should be encapsulated in concrete or the equivalent Designated areas should be impervious and paved with Portland cement concrete, free of cracks and gaps, in order to contain leaks and spills. it Liquid materials should be stored in UL approved double walled tanks or surrounded by a curb or dike to provide the volume to contain 10 percent of the volume of all of the containers or 110 percent of the volume of the largest container, whichever is greater. The area inside the curb should slope to a drain. For used oil or dangerous waste, a dead-end sump should be installed in the drain. All other liquids should be drained to the sanitary sewer if available. The drain must have a positive control such as a lock, valve, or plug to prevent release of contaminated liquids. Accumulated stormwater in petroleum storage areas should be passed through an oil/water separator. Maintenance is critical to preventing leaks and spills. Conduct routine inspections and: Check for external corrosion and structural failure. Check for spills and overfills due to operator error. Check for failure of piping system (pipes, pumps, flanger, coupling, hoses, and valves). Check for leaks or spills during pumping of liquids or gases from truck or rail car to a storage facility or vice versa. 6 of 9 California Stormwater BMP Handbook )anuary 2003 Industrial and Commercial www.cabmphafldbooks.com I... Spill Prevention, Control & Cleanup SC-li Visually inspect new tank or container installation for loose fittings, poor welding, and improper or poorly fitted gaskets. Inspect tank foundations, connections, coatings, and tank walls and piping system. Look for corrosion, leaks, cracks, scratches, and other physical damage that may weaken the tank or container system. Frequently relocate accumulated stormwater during the wet season. Periodically conduct integrity testing by a qualified professional. Vehicle leak and Spill Control Major spills on roadways and other public area are generally handled by highly trained Nazinat teams from local fire departments or environmental health departments. The measures listed below pertain to leaks and smaller spills at vehicle maintenance shops. In addition to implementing the spill prevention, control, and clean up practices above, use the following measures related to specific activities: Vehicle and Equipment Maintenance Perform all vehicle fluid removal or changing inside or under cover to prevent the run-on of stormwater and the runoff of spills. / Regularly inspect vehicles and equipment for leaks, and repair immediately. Check incoming vehicles and equipment (including delivery trucks, and employee and subcontractor vehicles) for leaking oil and fluids. Do not allow leaking vehicles or equipment onsite. Always use secondary containment, such as a drain pan or drop cloth, to catch spills or leaks when removing or changing fluids. Immediately drain all fluids from wrecked vehicles. Store wrecked vehicles or damaged equipment under cover. Place drip pans or absorbent materials under heavy equipment when not in use. Use adsorbent materials on small spills rather than hosing down the spill. Remove the adsorbent materials promptly and dispose of properly. a Promptly transfer used fluids to the proper waste or recycling drums. Don't leave full drip pans or other open containers lying around. OR filters disposed of in trashcans or dumpsters can leak oil and contaminate stormwater. Place the oil filter in a funnel over a waste oil recycling drum to drain excess oil before disposal. Oil filters can also be recycled. Ask your oil supplier or recycler about recycling oil filters. January 2003 California stormwater BMP Handbook 7 of 9 Industrial and Commercial www.cabmphandbooks.com SC-11 Spill Prevention, Control & Cleanu Store cracked batteries in a non-leaking secondary container. Do this with all cracked batteries, even if you think all the acid has drained out If you drop a battery, treat it as if it is cracked. Put it into the containment area until you are sure it is not leaking. Vehicle and Equipment Fueling Design the fueling area to prevent the run-on of stormwater and the runoff of spills: - Cover fueling area if possible. - Use a perimeter drain or slope pavement inward with drainage to a sump. - Pave fueling area with concrete rather than asphalt. If dead-end sump is not used to collect spills, install an oil/water separator. Install vapor recovery nozzles to help control drips as well as air pollution. Discourage "topping-off' of fuel tanks. Use secondary containment when transferring fuel from the tank truck to the fuel tank. a Use adsorbent materials on small spills and general cleaning rather than hosing down the area. Remove the adsorbent materials promptly. Carry out all Federal and State requirements regarding underground storage tanks, or install above ground tanks. Do not use mobile fueling of mobile industrial equipment around the facility; rather, transport the equipment to designated fueling areas. Keep your Spill Prevention Control and Countermeasure (SPCC) Plan up-to-date. Train employees in proper fueling and cleanup procedures. Industrial Spill Prevention Response For the purposes of developing a spill prevention and response program to meet the stormwater regulations, facility managers should use information provided in this fact sheet and the spill prevention/response portions of the fact sheets in this handbook, for specific activities. The program should: Integrate with existing emergency response/hazardous materials programs (e.g., Fire Department) Develop procedures to prevent/mitigate spills to storm drain systems a Identify responsible departments Develop and standardize reporting procedures, containment, storage, and disposal activities, documentation, and follow-up procedures Address spills at municipal facilities, as well as public areas 8 of 9 California Stormwater BMP Handbook January 2003 Industrial and Commercial www.cabmphandbooks.com Spill Prevention, Control & Cleanup SC-11 Provide training concerning spill prevention, response and cleanup to all appropriate personnel References and Resources California's Nonpoint Source Program Plan bttp:llwww.swrcb.ca.gov/nps/index.html Clark County Storm Water Pollution Control Manual http://www.co.clark.wa.us/pubworks/bmpinan.pdf King County Storm Water Pollution Control Manual http://dnr.metrokc.gov/wlr/dss/spcm.htm Santa Clara Valley Urban Runoff Pollution Prevention Program http://www.scvurppp.org The Stormwater Managers Resource Center http://www.stormwatercenter.net] January 2003 California Stormwater BMP Handbook 9 of 9 Industrial and Commercial www.cabmphandbooks.com Landscape Maintenance SC-73 Objectives Contain is Educate a Reduce/Minimize is P=W Substitution Targeted Constituents Sediment I lMstente I Trash I Baftle 01 and Gfeasa 0 Oxygen Demanding I Description Landscape maintenance activities Include vegetation removal; herbicide and Insecticide application; fertilizer application; wataft and other gardening and lawn care practices. Vegetation control typically Involves a combination of chemical (herbicide) application and mechanical methods. All of these maintenance practices have the potential to contribute pollutants to the storm drain system. The major objectives of this BMP are to minimize the discharge of pesticides, herbicides and fertilizers to the storm drain system and receiving waters; prevent the disposal of landscape waste into the storm drain system by collecting and properly disposing of clippings and cuttings, and educating employees and the public, Approach Pollution Prevention a Implement an Integrated pest management (IPM) program. IPM is a sustainable approach to managing pests by combining biological, cultural, physical, and chemical tools. a Choose low water using flowers, trees, shrubs, and groundcover. Consider alternative landscaping techniques such as naturescaping and xeriscaping. a Conduct appropriate maintenance (i.e. properly timed X SQ A fertilizing, weeding, pest control, and pruning) to help preserve ) California the landscapes water efficiency. Stormwater ' Ouaiity Association January 2003 California Stortnwater BMPtlandboolc 1 of 6 Municipal wwrhmnhw,knm SC-73 Landscape Maintenance is Consider grass cycling (grass cycling is the natural recycling of grass by leaving the clippings on the lawn when mowing. Grass clippings decompose quickly and release valuable nutrients back Into the lawn). Suggested Protocols Mowing, Trimming, and Weeding Whenever possible use mechanical methods of vegetation removal (e.g mowing with tractor- type or push mowers, hand cutting with gas or electric powered weed trimmers) rather than applying herbicides. Use hand weeding where practical. Avoid loosening the soil when conducting mechanical or manual weed control, this could lead to erosion. Use mulch or other erosion control measures when soils are exposed. Performing mowing at optimal times. Mowing should not be performed if significant rain events are predicted. Mulching mowers may be recommended for certain flat areas. Other techniques may be employed to mhlinthó mowing such as selective vegetative planting using low maintenance grasses and shrubs. Collect lawn and garden clippings, pruning waste, tree trimmings, and weeds. Chip if necessary, and compost or dispose of at a landfill (see waste management section of this fact sheet). a Place temporarily stockpiled material away from watercourses, and berm or cover stockpiles to prevent material releases to storm drains. Planting a Determine existing native vegetation features (location, species, size, function, importance) and consider the feasibility of protecting them. Consider elements such as their effect on drainage and erosion, hardiness, maintenance requirements, and possible conflicts between preserving vegetation and the resulting maintenance needs. a Retain and/or plant selected native vegetation whose features are determined to be beneficial, where feasible. Native vegetation usually requires less maintenance (e.g., Irrigation, fertilizer) than planting new vegetation. Consider using low water use groundcovers when planting or replanting. Waste Management a Compost leaves, sticks, or other collected vegetation or dispose of at a permitted landfill. Do not dispose of collected vegetation into waterways or storm drainage systems. Place temporarily stockpiled material away from watercourses and storm drain inlets, and berm or cover stockpiles to prevent material releases to the storm drain system. s Reduce the use of high nitrogen fertilizers that produce excess growth requiring more frequent mowing or trimming. 2 of 6 - - California Stonnwater 6MP Handbook January 2003 Municipal - Landscape Maintenance SC-73 Avoid landscape wastes in and around storm drain inlets by either using bagging equipment or by manually picking up the material Irrigation Where practical, use automatic timers to minimize runoff. use opupskler heads with a lot Of activity Or where there a chance the pipes may be broken. Consider the use of mechanism R that reduce water flow to sprinkler heads If broken. Ensure that there Is no runoff from the landscaped area(s) If re-claimed water Is used for irrigation. If bailing of muddy water. Is required (e.g. when repairing a water line leak), do not put It In the storm drain; pour over landscaped areas. Irrigate slowly or pulse Irrigate to prevent runoff and then only Irrigate as much as is Apply water at rates that do not exceed the infiltration rate of the soil. Fertilizer and Pesticide Management Utilize a comprehensive management system that incorporates Integrated pest management (IPM) techniques. There are many methods and types of IPM, Including the following. - Mulddng can be used to prevent weeds where turf Is absent, fencing Installed to keep rodents out, and netting used to keep birds and Insects away from leaves and fruit - Visibleinsects can be removed by hand (with gloves or tweezers) and placed in soapy water or vegetable oil. Alternatively, Insects can be sprayed off the plant with water or in some cases vacuumed off of larger plants. - Store-bought traps, such as species-specific, pheromone-based traps or colored sticky cards, can be used. - Slugs can be trapped in small cups filled with beer that are set in the ground so the slugs can get In easily. - In cases where microscopic parasites, such as bacteria and fungi, are causing damage to plants, the affected plant material can be removed and disposed of (pruning equipment should be disinfected with bleach to prevent spreading the disease organism). Small mammals and birds can be excluded using fences, netting, tree trunk guards. - Beneficial organisms, such as bats, birds, green lacewings, ladybugs, praying mantis, ground beetles, parasitic nematodes, trichogramina wasps, seed head weevils, and spiders that prey on detrimental pest species can be promoted. a Follow all federal, state, and local laws and regulations governing the use, storage, and disposal of fertilizers and pesticides and training of applicators and pest control advisors. january 2003 - California Stormwater 8MP handbook 3 of 6 Municipal - www.cabmphandbooks.com SC-73 Landscape Maintenance Use pesticides only if there is an actual pest problem (not on a regular preventative schedule). Do not use pesticides if rain is expected. Apply pesticides only when wind speeds are low (less than 5 mph). Do not mix or prepare pesticides for application near storm drains. Prepare the minimum amount of pesticide needed for the job and use the lowest rate that will effectively control the pest. Employ techniques to minimize off-target application (e.g. spray drift) of pesticides, including consideration of alternative application tecbnlques. Fertilizers should be worked Into the soil rather than dumped or broadcast onto the surface. Calibrate fertilizer and pesticide application equipment to avoid excessive application. Periodically test soils for determining proper fertilizer use. Sweep pavement and sidewalk if fertilizer is spilled on these surfaces before applying irrigation water. Purchase only the amount of pesticide that you can reasonably use in a given time period (month or year depending on the product). Triple rinse containers, and use rinse water as product Dispose of unused pesticide as hazardous waste. Dispose of empty pesticide containers according to the instructions on the container label. Inspection Inspect irrigation system periodically to ensure that the right amount of water is being applied and that excessive runoff Is not occurring. Minimize excess watering, and repair leaks in the irrigation system as soon as they are observed. Inspect pesticide/fertilizer equipment and transportation vehicles daily. Training Educate and train employees on use of pesticides and in pesticide application techniques to prevent pollution. Pesticide application must be under the supervision of a California qualified pesticide applicator. Train/encourage municipal maintenance crews to use IPM techniques for managing public green areas. a Annually train employees within departments responsible for pesticide application on the ( appropriate portions of the agency's IPM Policy, SOPs, and BMPs, and the latest IPM I techniques. 4 of 6 California Stormwater BMP Handbook January 2003 I Municipal www.cabmphandbooks.com Landscape Maintenance SC-73 Employees who are not authorized and trained to apply pesticides should be periodically (at least annually) informed that they cannot use over-the-counter pesticides In or around the workplace. Use a training log or similar method to document training Spill Response and Prevention Refer to SC-ii, Spill Prevention, Control & Cleanup i Have spill cleanup materials readily available and in a know in location Cleanup spills Immediately and use dry methods if possible. Properly dispose of spill cleanup materIL Other Considerations The Federal Pesticide, Fungicide, and Rodent dde Act and California ThIe 3, Division 6, Pesticides and Peat Control Operations plate strict controls over pesticide application and handling and specify training, annual refresher, and testing requirements. The regulations generally cover a list of approved pesticides and selected uses, updated regularly, general application Information; equipment use and maintenance procedures; and record keeping. The California Department of Pesticide Regulations and the County Agricultural Commission coordinate and maintain the licensing and certification programs. All public agency employees who apply pesticides and herbicides in*agricultural use" areas such as parks, golf courses, rights-of-way and recreation areas should be properly certified in accordance with state regulations. Contracts for landscape maintenance should include similar requirements. All employees who handle pesticides should be familiar with the most recent material safety data sheet (MSDS) files. Municipalities do not have the authority to regulate the use of pesticides by school districts, however the California Healthy Schools Act of 2000 (AB 226o) has imposed requirements on California school districts regarding pesticide use in schools. Posting of notification prior to the application of pesticides Is now required, and IPM Is stated as the preferred approach to pest management in schools. Requirements Coats Additional training of municipal employees will be required to address IPM techniques and BMPs.. IPM methods will likely increase labor cost for pest control which may be offset by lower chemical costs. Maintenance Not applicable January 2003 California Stormwater BMP Handbook 5 of 6 Municipal www.cabmphandbooks.com SC73 Landscape Maintenance Supplemental Information Further Detail af the BMP Waste Management Composting is one of the better disposal alternatives if locally available. Most municipalities either have or are planning yard waste composting facilities as a means of reducing the amount of waste going to the landfill Lawn clippings from municipal maintenance programs as well as private sources would probably be compatible with most composting facilities Contractors and Other Pesticide Users Municipal agencies should develop and implement a process to ensure that any contractor employed to conduct pest control and pesticide application on municipal property engages In pest control methods cosltent with the IM Policy adopted by the agency. Specifically, municipalities should require contractors to follow the agency's IPM policy, SOPs, and BMPs; provide evidence to the agency of having received training on current IPM techniques when feasible; provide documentation of pesticide use on agency property to the agency in a timely manner. References and Resources > King County Stormwater Pollution Control Manual. Best Management Practices for Businesses. - ig. King County Surface Water Management. July. On-line: Los Angeles County Stormwater Quality Model Programs. Public Agency Activities Model Urban Runoff Program: A How-To Guide for Developing Urban Runoff Programs for Small Municipalities. Prepared by City of Monterey, City of Santa Cruz, California Coastal Conthilsslon, Monterey Bay National Marine Sanctuary, Association of Monterey Bay Area Governments, Woodward-Clyde, Central Coast Regional Water Quality Control Board. July. 1998. Orange County Stormwater Program Santa Clara Valley Urban Runoff Pollution Prevention Program. 1997 Urban Runoff Management Plan. September 1997, updated October 2000. United States Environmental Protection Agency (USEPA). 2002. Pollution Prevention/Good Housekeeping for Municipal Operations Landscaping and Lawn Care. Office of Water. Office of Wastewater Management. On-line: http://www.epa.aovinodes/menuofbmps/poll 8.htm 6 of 6 California Stormwater BMP Handbook January 2003 Municipal www.cabmphandbooks.com Section 7.0 Structural Treatment BMPs Based upon the categories in Table 2— Anticipated and Potential Pollutants Generated by Land Use Type, pollutants of concern for this project include: sediment, nutrients, heavy metals organic compounds, trash and debris, oxygen demanding substances, bacteria, oil and grease, and pesticides. (See attached Table 2) To minimize pollutants of concern, we are using: Multiple Systems - BMPs using different removal processes will be combined to improve overall removal efficiency. (See Fact Sheet TC-60) The two selected, where possible, are the direction of polluted runoff through a vegetated swale prior to entering a storm drain with inlet baskets. Storm drain inlet baskets - Storm drainage inserts will be used for Structural Treatment BMPs. The drainage inserts will be catch basin baskets. The drainage inserts are Suntree Technologies Inc. products. (See attached manufacturer's information) Based upon Table 3— Numeric Sizing Treatment Standards, we are using a flow-based BMP designed to mitigate, (infiltrate, filter or treat) the maximum flow rate or runoff produced from a rainfall intensity of 0.2 inches of rainfall per hour for each hour of a storm event. The attached manufacturer's information specifies flow capacity for each drainage structure. Flow rates into each catch basin have been checked to ensure they are within treatment capacity (see Drainage Study for catch basin flow rates.) Storm Water Standards 4103/03 0. Now ir :SELUTIOU 10 DU : •. ...':.:.• :. When referred to this Section, by Step 2 of Section II, complete the analysis required for your project In the subsections of Section 111.1 below. 1. IDENTIFY POLLUTANTS & CONDITIONS OF CONCERN A. Identify Pollutants from the Project Area Using Table 1, identify the projects anticipated pollutants. Pollutants associated with any hazardous material sites that have been remedlated or are not threatened by the proposed project are not considered a pollutant of concern. Projects meeting the definition of more than one project category shall Identify all general pollutant categories that apply. Table 2. Mticlpated and Potential Pollutants Generated by Land Use Two. General Pollutant Categodu Trash Oxygen Bacteria cat4vtaa Heavy Organic & Demanding OR & & Sediments Nutrients Metals Compounds Debris Substances Grease Viruses Pesticides Detached Residential X X X X X X x. Attached Residential X X X PIt) PM P1') X Development Comrnerdal Developmint P1') P1') PM X PM X P33 1315) >100,M01113 Automotive r X X(4X5) X X Repai Restaurants X X X X HI slde Development X X . X X X x 4000 ft2 Parking Lots P11) P1) X X P(') X p(1) Streets, Highways & X p(1) X . X (5) Freeways X= anticipated P = potential A potential pollutant if landscaping exists on-site. A potential pollutant if the project includes uncovered parking areas. A potential pollutant if land use involves food or animal waste products. Including petroleum hydrocarbons. Including solvents. . - Storm Water Standards 4103103 ill ERM31ENt BEST MANAGEMENtPRACTRE8 SELE1ONPRoCEtiAE When referred to this Section, by Step 2 of Section II, complete the analysis required for your project in the subsections of Section 111.1 below. 1. IDENTIFY POLLUTANTS & CONDITIONS OF CONCERN A. Identify Pollutants from the Project Area Using Table 1, identify the projects anticipated pollutants. Pollutants associated with any hazardous material sites that have been remedlated or are not threatened by the proposed project are not considered a pollutant of concern. Projects meeting the definition of more than one project category shall Identify all general pollutant categories that apply. Table Z. Mticlpated and Potential Pollutants Generated by Land Use lvi,.. G.nsraIP,IMantcategc,fs P1o'ect Trash Oxygen Bacteria Ca'"odOa Heavy Organle & Demanding 01 a a Sediments Nutrients Metals Compounds Debris Substances Grease VirusesPestictdes Detached Residential X X Development X X X X x. Attached Residential X X X PC') P(5) PC') X Deveinpmenl commerdal Development P(l) SC') PC5) X P15) X P. P0) >10000ft' Automotive R X )4X5) Restaurants . X X X X Hillside Development X X X X X x >5,000 ft2 Parking Lots P0) PM x X PC1) X pm Streets, Highways & X PX X X14 X P(S) X Freeways XanticIpated Ppotential A potential pollutant if landscaping exists on-site. A potential pollutant If the project includes uncovered parking areas. A potential pollutant if land use involves food or animal waste products. IncludIng petroleum hydrocarbons. 1(5) Including solvents. Storm Water Standards 4103/03 Table 3. Numeric Volume Votumebased BMPs shall be designed to mitigate (infiltrate, filter, or treat) the volume of runoff produced from a 24-hour 85 percentile storm event, as determined from Isopluvial maps contained In the County of San Diego Hydrology Manual. KO Flow Flow-based BMPs shall be designed to mitigate (infiltrate, filter, or treat) the maximum flow rate of runoff produced from a rainfid Intensity of 0.2 Inch of rainfall per hour for each hour of a storm evert I. Structural Treatment BMP Selection Procedure Priority projects shall select a single or combination of treatment BMPs from the categories in Table 4 that maximize pollutant removal for the particular pollutant(s) of concern. A ny pollutants the project Is expected to generate that are also causing a Clean Water Act section 303(d) Impairment of the downstream receiving waters of the project should be given top priority in selecting treatment BMPs. To select a structural treatment BMP using the Structural Treatment Control BMP Selection Matrix (Table 4), each priority project shall compare the list of pollutants for which the downstream receiving waters are impaired (II any). According to the 1998 303(d) listing, the Ague Hedionda Lagoon is impaired for sediment and siltation. Buena Vista Lagoon also has impaired beneficial uses (aquatic life) due to high sedlmehtation/siltatlon. Portions of Carlsbad where construction sites have the potential to disciarge Into a tributaryof a 303(d)or dlrectlyinto a 303(d)water body or sites located! within 200 feet of an ESA require additional BMP implementation. These water bodies Include the Pacific Ocean, Buena Vista Lagoon, Encinas Creek, Agua Hedionda Lagoon, and Batiquitos Lagoon. Priority projects that are not anticipated to generate a pollutant for which the receiving water is Clean Water Act Section 303(d) Impaired shall select a single or combination of structural treatment BMPs from Table 4 that are effective for pollutant removal of the identified pollutants of concern determined to be most significant for the project. Selected BMPs must be effective for the widest range of pollutants of concern anticipated to be generated by a priority project (as Identified in Table 1). Alternative storm water BMPs not identified in Table 4 may be approved at the discretion of the City Engineer, provided the alternative BMP is as effective in removal of pollutants of concern as other feasible BMPs listed in Table 4. itorm Water Standards 4103103 Table 4. Structural Treatment Control BMP Selection Matrix. Poltigtant of Concern Treatment Confrol BMP Categories betenUon bfihtratIon Wet Ponds or alnage Filtration Hydrodynamic SW) BasIns Basins(1) Wetlends serts SepaatorSystemsZ Sediment 11 if H H H PA Nutrients I PA PA PA L N HeaMets N PA N H L H I OranIo Compounds U U U u : PA L Trash &Mile I H U U PA H N O5fldlfl L N PA Sebsces• PA I M L Bacteria I .0 H U I N I Cl&Orease I U PA U U I H I Pesilddes I U I U. U U L U L (1) Inckft trenches aid porous paveme (2) Also knomi en h*ndynamlo devices and baffle bmwa L Low miaW efflc1icy M Medium removid efficiency H: High remov efficiency th Unluiewn removid efficiency Soumes GiIdanc Spedt*,g Managerned Maaswes for Soavea of NonpoL'it Pollution In Coastal Waters (1993), Wa,al. Stomnvater Beat Managemeef Pac&es Database (2001)h and Guide for BMP Seioctlon In U,ban Oet1oped Areas (2001). H. Restrictions on the use of Infiltration Treatment BMPs 31. Treatment control BMPs that are designed to primarily function as infiltration devices shall most the following conditions (these conditions do not apply to treatment BMPs which allow, Incidental Infiltration and are riot designed to primarily function as infiltration devices, such as grassy swales, detention basin s , vegetated buffer strips, constructed wetlands, etc.): (1) urban runoff from commercial developments shall undergo pretreatment to remove both physica l a n d c h e m i c a l contaminants, such -as sedimentation or filtration, prior to infiltratio n ; ( 2 ) all dry weather flows shall be diverted from Infiltration devices except for those non-storm water discharges authorized pursuant to 40 CFR 122.26(d)(2)(iv)(BXI): diverted stream flows, rising ground waters, uncontaminated ground water i n f i l t r a t i o n [ a s defined at 40 CFR 35.2005(20)1 to storm water conveyance systems, uncontaminated pumped ground water, foundation drains, springs, w a t e r f r o m crawl space pumps, footing drains, air conditioning condensation, f l o w f r o m riparlan habitats and wetlands, water line flushing, landscape inlgatlon, discharges from potable water sources other than water main breaks, irrig a t i o n w a t e r , Individual residential car washing, a nd d echiorinated swimming po o l d i s c h a r g e s ; (3) pollution prevention and source control BMPs shall be implemente d a t a l e v e l appropriate to protect groundwater quality at sites where infiltrat i o n s t r u c t u r a l treatment BMPs are to be used; (4) the vertical distance from the ba s e o f a n y infiltration structural treatment BMP to the seasonal high groundwater m a r k s h a l l be at least 10 feet. Where groundwater does not support beneficia l u s e s , t h i s vertical distance criterion may be reduced, provided groundwat e r q u a l i t y i s Targeted Constituents f Sediment / Nuttients / Trash / Metals Bacteria / 011and Grease /crganlcs RowdEffecdvenss See Now Development and Redevelopment Handbook-SectIon 5. Drain Inserts MP-52 Description Drain inserts are manufactured filters or fabric placed In a drop inlet to remove sediment and debris. There are a multitude of Inserts of various shapes and configurations, typically falling Into one of three different groups: socks, boxes, and trays. The sock consists of a fabric, usually constructed of polypropylene. The fabric may be attached toa frame Or the grate of the inlet holds the sock. Socks are meant for vertical (drop) Inlets. Boxes are constructed of plastic or wire mesh. Typically a polypropylene 'bag' is placed in the wire mesh box. The bag takes the form of the box. Most box products are one box; that Is, the setting area and filtration through media occur in the same box. Some products consist of one or more trays or mesh grates. The tTays may hold different types of media. Filtration media vary b manufacturer. Types Include polypropylene, porous polymer, teated ceibdose, and activated carbon. California Experience The number of installations is unknown but likely exceeds a thousand. Some users have reported that these systems require considerable maintenance to prevent plugging and bypass. Advantages a Does not require additional space as inserts as the drain inlets are already a component of the standard drainage -S. a Easy access for inspection and maintenance. a As there is no standing water, there is little concern for mosquito breeding. i A relatively inexpensive retrofit option. Umitatlons Performance is likely significantly less than treatment systems that are located at the end of the drainage system such as ponds and vaults. Usually not suitable for large areas or areas with trash or leaves than can plug the insert. Design and Sizing Guidelines Refer to manufacturer's guidelines. Drain inserts come any many configurations but can be placed into three general groups: socks, boxes, and trays. The sock consists of a fabric, usually constructed of polypropylene. The fabric maybe attached to a frame or the grate of the inlet holds the sock. Socks are meant for vertical (drop) inlets. Boxes are constructed of plastic or wire mesh. Typically a pulypropylene bag" is placed in the wire mesh box. The bag takes the form of the box. Most box. products are Design Considerations a Use with other 8MPs is Fit and Seal Capacity within Inlet Al A CalIfovria orniwatr uaII2y ItL).i1 January 2003 Califo,nia Stormwater BMP Handbook t or 3 New Development and Redevelopment - -- - www.cabmthandbooks.com MP-52 Drain Inserts one box that is, the setting area and filtration through media occurs in the same box. One manufacturer has a double-box. Stormwater enters the first box where setting occurs. The stormwater flows into the second box where the filter media is located. Some products consist of one or more trays or mesh grates. The trays can hold different types of media. Filtration media vary with the manuhcturer types include polypropylene, porous polymer, treated cellulose, and activated carbon. Construction/Inspection Considerations Be certain that installation is done in a manner that makes certain that the stormwater enters the unit and does not leak around the perimeter. Leakage between the frame of the Insert and the frame of the drain Inlet can easily occur with vertical (drop) Inlets. Performance Few products have performance data collected under field conditions. Siting Criteria It Is recommended that inserts be used only for retrofit situations or as pretreatment where other treatment BMPs presented In this section area used. Additional Design Guidelines Follow guidelines provided by Individual manufacturers. Maintenance Likely require frequent maintenance, on the order of several times per year. Cost e The initial cost of Individual Inserts ranges from less than $100 to about $2,000. The cost of using multiple units in curb inlet drains varies with the size of the inlet. NiThe low cost of inserts may tend to favor the use of these systems over other, more effective treatment BMPs. However, the low cost of each unit may be offset by the number of units that are required, more frequent maintenance, and the shorter structural life (and therefore replacement). References and Sources of Additional Information Hrachovec, R., and G. Minton, 2001, Field testing of a sock-type catch basin insert, Planet CPR, Seattle, Washington Interagency Catch Basin Insert Committee, Evaluation of Commercially-Available Catch Basin Inserts for the Treatment of Stormwater Runoff from Developed Sites, 1995 Larry Walker Associates, June 1998, NDMP Inlet/In-Line Control Measure Study Report Manufacturers literature ( Santa Monica (City), Santa Monica Bay Municipal Stormwater/Urban Runoff Project - Evaluation of Potential Catch basin Retrofits, Woodward Clyde, September 24, 1998 2o3 ew,ki DvcIopment and RedeeIOPrn.nt Drain Inserts S MP-52 Woodward Clyde, June it, 1996, Parking Lot Monitoring Report Santa Clara Valley Nonpoint Source Pollution Control Program. January 2003 California Stormwater BMP Handbook 3 3 New Development and Redevelopment www.cabmoliandbooks.com rà3 ENVIRONMENTAL SERVICES, INCI Grate Inlet Skimmer Box Curb Inlet Basket Nutrient Separating Baffle Box REPORTS & DATA Pollutant Loading Analysis for Stormwater Retrofitting In Melbourne Beach, Florida Pollutant Removal Testing for A Suntree Technologies Grate Inlet Skimmer Box Site Evaluation of Suntree Technologies, Inc. Grate Inlet Shimmer Boxes for Debris, Sediment And OR & Grease Removal ç flGN ThL ' 3* A _i1,Iá'%4 II VV PYAWA I.4-14.4'Vi Pollutant Loading Analysis For Stormwater Retrofitting in Melbourne Beach, Florida By: Cordon England, P.E. Creech Engineer., Inch 4450 W. Eau GaUl. Blvd, #232 Melbourne, FL 32932 Introduction At Gemini Elementary School in Melbourne Beach, Florida, there has been a history of repeated flooding on the school grounds and in properties adjacent to the schooL In 1999 Creech Engineers, me. (CE!) was chosen by Brevard County Stormwater Utility to design drainage improvements to alleviate these flooding conditions, as well as to provide for stormwater treatment within this 20.06 hectare drainage basin. The project was divided into two phases. Phase I improvements were made in order to accelerate initial flood control measures for homes downstream of the school Phase 2 involved the design of more extensive flood and water quality control measures along Oak Street for further protection of school property and roadway flooding at nearby church property. This paper highlights the political challenges of retrofitting storniwater systems in developed areas, as wellàs denxmstrates a methodology for performing a imnpoh source pollutant loading analysis. Existing Conditions Gemini Elementary School is located on a 8.02 hectare, triangular shaped property along the south side of Oak Street, a two lane collector road in Melbourne Beach, about one half mile from the Atlantlo Ocean. See Exhibit 1. Residential properties He downstream of the school, along its southeast and southwest borders. 8.51 hectare Doug FlutiePark is on the north side of Oak Street A soccer club uses the park and school grounds on a daily basis. There was no stormwater system at the park, along Oak Street or on the school site. Stormwater flowed southward off Doug Flutis Park, across Oak Street through the school site, and into the yards and homes south of the school These yards, and the roads downstream of them, are very flat and only a few feet above sea level Once water stages high enough in the yards, it gradually sheetfiows down the adjacent roads a few hundred yards to the Indian 1biVCT. The acted homeowners naturally blamed the school for allowing the school's water to flood them. West of the school, a few bundred yards along Oak Street, was a low go* in the road when water ponded and flooded the road and an adjacent churchyard. Due to a thin clay lens at 26 cm deep causing a perched water table, water stood in the road for several days after even a nominal rainfall. This drainage basin was almost completely built out, with no easy path for developing outihils to relieve flooding. This section of the Indian Rivet is a Class 2 water body, with a Shellfish Harvesting classification bringing intense scrutiny from the St. Johns River Water Management District Corp of Engineers permitting is required for new 0tthfli in the area due to seagrasses new the shoreline The park, the school, and Oak Street He in unincorporated Brevard County. The church, and properties west of the school are in Melbourne Beach. Being a collector road, all of the utility companies have major transmission lines in the road right-of-way. As can be seen, this challenging project involved Brevard County, Melbourne Beach, the School Board, Brevard County Parks and Recreation Department, Brevard County Road and Bridge Department, Brevard County Stonuwater Utility, a church, three different Homeowners Msociations,. a soccer club, the Water Management District, the Corp of Engineers, and several utility companies. Stakeholder involvement and partnerships were going to be critical to weave a solution through the many players involved. Proposed Improvem eats The first priority was to alleviate flooding in the homes adjacent to the school As an interim measLwe, a berm was designed and constructed by County personnel along the south property lines of the school, with a swale behind the berm directing water to the southernmost point of the school property. At that location, an inlet and 18" outfall pipe were constructed in a utility easement through two heavily landscaped and knced yards, to Pompano Street, where it was tied into an existing storm drain pipe A short time later, heavy rains overflowed the harms and males and flooded homes adjacent to the school igain- CEI was engaged at that point to provide more effective drainage improvements. Fortunately, Gemini Elementary School had a significant area of vacant land on their site. The school entered into agreements with Brevard County allowing the construction of three dry retention ponds totaling 2.95 bectare to reduce flows leaving the school site, as well as provide stormwater treatment where none existed. These dry ponds were wound around several soccer and baseball fields. The soccer field's locations had to remain in place due to previous agreements with the school and Parks and Recreation Dept. The ponds were only 26-40 cm (12"- 18") deep and sodded, allowing the soccer teams to use the pond areas as practice fields when dry. When the ponds were excavated, the confining clay layer was removed to allow for infiltration though the beach sand at the site. Construction was scheduled during the summer when school was out. A control structure was designed at the outfall pipe location to provide protection for a 25 year storm. The temporary connection to the existing downstream pipe had overloaded the downstream system in a heavy rain Cvent, so a new outfall to the kdian River was designed, through a ,ark adjacent to the River. The park was owned by i oowrees 2 Association, which rehictantly gave a drainage easement through the park. The County agreed to make several improvements to the park and its boat ramp in exchange for the easement. The Corp of Engineers was concerned that the new outfall pipe discharges would impact the nearby seagrasses, so the new discharge pipe was not permitted to be constructed in the Indian River. A bubbleup box was designed ten feet back from the shoreline and rock riprap was placed between the bubbleup box and the mean high water line to prevent erosion. As mitigation for disturbing the shoreline, spartina and other plants were planted among the rocks to farther buffer the shoreline from the storniwater discharges. This first ple of improvement' was finished in September 2000 at a cost of $124,000. The improvements implemented proved successful in preventing any flooding of adjacent homes in several large rainfilla in 2001. The second phase of the project addressed stonflwater quantity and quality concerns along 1650 teeters of Oak Street, from AlA to Cherry Street. To provide fiutha flood protection at Genthil Elementary School, retention swales were designed along both sides of Oak. Street and 625 metus, of storm drain pipe was designed to intercept nmoff and prevent it from crong the road onto school property. The piping also provided an out" for thelow spot in the road by the; church, This new pipe system discharged into a residential cad system, which was used by many of the adjacent residents for boating to the Tnrlian River Lagoon (Bay). These canal' were very political, sensitivesinc. they were in need of dredging and the Town of Melbourne Beach does not dredge canals. The residents were concerned that the new storniwater "=would lead to farther sedimentation of the ca"i'- 'Iba. first alternative for treatmeid was to use land at the church site for a pond for the road runoff: The church was willing to donate the land where their septic tank fields were located if the County would provide a sewer connection. This scenario was designed, but when it came time for the church to give easements to the County, they balked and it was back to the drawing board. St. Johns River Water Management District, (District), criteria requires stormwater treatment for improvements which a) increase discharge rates b) which increase, pollutant loadings, or c) which increase impervious areas. With this project, no new increased impervious areas were proposed, but there would be additional water flowing to the residential canal from the extension of the pipe system to the flood prone areas. These new flows create the potential for increased poftant -loadings to the canal Normal design methods would have used treatment ponds to offset these potential impacts. Due to lack of available land for ponds, alternative Ireatment methods were proposed for this project The District will consider alternative treatment methods if it can be demonstrated that all other possible alternatives have been exhausted. It would not be possible politically to use more school or park area for treatment ponds. For this project, CEI showed that the only alternatives were to tear down houses for poads, or use alternate treatment technologies. The treatment strategy involved maximizing treatment methods within the project basin with alternative BMPs, as well as retrofitting two adjacent watersheds as additional mitigation. A total of 1.67 acre feet of retention storage was provided in Phase 2 in the roadside swales and small ponds. This was equivalent to 0.032 inches of retention from the drainage areas flowing to the retention areas. A treatment train along Oak Street was designed by using 9 Grated Inlet Skimmer Boxeso from Suntree Technologies, Tm., in the new inlets to trap debris entering the inlets, constructing berms to slow runoff thm the ball fields, and installing one baffle box at the downstream end of the new pipe system along Oak Street Baffle Boxes are in-line stormwater tr.thnt devices which trap sediment, trash, and debris. They have been used by Brevard County successfully for the he 9 years. In olts Basin 4, which only had one existing baffle box to provide sediment removal, 16 Curb Inlet Skimmer Boxes were installed in all of the existing inlets to provide nutricit removal by trapping grass clippings, leaves, and yard debris. Nutrients were a concern in the canals since the nutrients promote algae blooms, which in turn Increase nmrk Mild up in the canals. In offbito drainage Basin 5, there are 3 existing pipes which dlschàge directly to the canals Three baffle boxes and 6 curb inlet skimmer boxes were designed to provide sediment and nutrient treatment for this drainage basin. Brevard County Stormwatar Utility will implement this project and be responsible for all maintenance of the improvements. 11 baffle boxes will be inspected twice a year and cleaned as needed. The inlet traps will be cleaned twice a year. Brevard County has a vacuum truck dedicated to cleaning stormwatet BMPs... Using numerous BMPs used on this préject provided a high degree of treatment for the new piping system along Oak Street, and provided treatment for two offsite beams where little treatment existed. The retrofitting of the offaite areas was, in effect, mitigation for the new discharges to the canal. See Exhibit 1 for a map of the hnpiuvements. Calculations In Phase 1 of the project, the dry ponds and outthll pipes were modeled hydraulically using the Interconnected Pond Routing program. Since the dry ponds in the Phase 2 project area were too small to provide effective attenuation, the predevelopment and post development runoff calculations were made using Hydraflow and the rational method. no only available storm drain pipe for Phan 2 was a 36' pipe in offshe Basin 4. The new piping along Oak Street was connected to the existing 36" pipe, and the piping downstream of the connection was upgraded to a 42" pipe The pipes were designed for a25 year storm. Basins l,2, and 3 were amuch longerdistance from theoutfaljthan Basin 4. As a result of different times of concentration, the peak flows from Basin 4 passed sooner than Basins 1,2, and 3, giving only a slight increase in peak discharge, despite adding 12.25 hectares to the area flowing to the existing out&IL The potential for increased pollutant !oadings in the canal system was a conceal of !oea1 residents. These canals had a history of dredging operations every 3-10 years, and the residents did not want to increase the frequency of costly dredging. The main pollutants of concern leading to muck deposition in the canals were Total Suspended Solids (TSS), Total Nitrogen (In and Total Phosphorus (fP) Sediment build up at the and of the pipes was comm Nutrient loadings from grass cipphgs, leaves, and fertilizers leads to algae blooms and low dissolved oxygen in the canals, which in turn leads to muck build up from the eutrophication process. Most of the materiel dredged from residential canals is typically muck To address this concern, a pollutant loading analysis of the existing and proposed stormwater discharges was performed. In the existing conditions, the only stonuwater treatment fl)r the canal system was a baffle box along Cherry Street for oite Basin 4 of 24.24 hectares. There were a total of 7 outfall pipes discharging into the canal system In the first phase of this project stormwater lit ea In, rt was provided for 8.02 hectares of the school grounds with 3 dry detenton ponds. The discharge from these ponds was to the Indian River, rather than the canal system, so these pollutant loads were not Included in the pollutant load analysis for the canal outlL The existing pollutant load to the canal only cam from the drainage Basins 4 and 5, totaling 31.2 bectares. The runoff from Oak Street did not drain to the canal in existing conditions, only in the post development com4itinns. The strategy for the pollutant analysis was to calculate the pollutant loads in the existing contfltinns, and then calculate the pollutad loads after the now pipes were added to the system and oite areas retrofitted for stormwater treatniut. The pollutants used in this analysis were TSS, TP, and TN. Each drainage basin was categorized by land use. Areal, annual, naaa loading rates from "Stormwater Loading Rate Parameters for Central and South Florida", Harper, 1994, were multiplied by each basin's area to give existing and potential annual pollutant loadings See Table 1. The next step was to calculate the pollutant removal rates for the different BMPs. Individual BMP removal efficiencies were take from "A Guide for BMP Selection in Urban Developed Areas", EWRI 2000. What was challenging with this analysis was the use of multiple BMPs in series for the treatment train. Each BMP receives cleaner and cleaner water as the water moves down the train. At each BMP, the removal efficiency for each constituent was multiplied by the remaining percentage of the initial loading to give a wegbted, cumulative, removal efficiency for each constituent. See Table 2. These calculated removal efficiencies were then multiplied by the total calculated pollutant loads to give the reduced pollutant loadings after the BMPs were installed. See Table 3. Table 4 shows that the total loads to the canal were reduced as a result of the retrofitting of onsite and offsite basins. The pollutant loading analysis below demonstrates that as a result of the Ilumerous 3MPs proposed, the total pollutant loadings aiate&g the canals alter project completion will actually be signiflcanty reduced from the existing pollutant loadings entering the canals. The key to overall pollutant reduction is to provide additional treatment in offsite drainage basins. This will result in a net benefit of reduced pollutants entering the canals and a reduction of the severe flooding often seen along Oak Street. Table I Existing Pollutant Loading Basin Area (acres) Land Us. Loading Rate* (kglac.y.ar) Potential Pollutant Loading (kg-year) TSS Total Phosphprus Total Nitrogen T$S Total Phpltoi TOtal. Nlfro 2A 9.23 Recrestlniot 7.6 0.046 107 7015 0.425 9.875 28 1.15 RecreMlanal 7.6 0.046 1.07 8.74 0.053 1.231 20 0.17 Recreallonal 7.6 0.045 1.07 585 0.035 0.824 20 1.45 ------ 00--d 7.6 0.046 1.07 11.(Q 0.007 1.5 2E 2.83 IR&mfonal 7.6 0.046 1.01 19.99 0.121 2.814 I 2F 1.97 Recilcnal 7.6 0.046 1.07 i497 0.091 2.108 2(3 0.78 Ronlon 7.6 0.046 1.07 9.70 0.035 0.803 2H 1.25 Rea-mak -d 7.8 0.046 1.01 9.80 0059 1.380 21 0.08 Recreadand 7.6 0.046 1.07 0.61 0.004 0.086 2.1 0.8 Rwask 11 7.6 0.048 107. 6.00 0.037 0.850 2K 0.57 Rsciiemonal 7.6 0.040 1.01 4.33 0.16 0.610 I 2L 0.34 Reaneft -ol 7.6 0.046 1.07 2.51 0.018 0.394 3A 119 S1nsFatv 56.1 0.594 4.68 1.86 1.301 10249 35 &( 56.1 0.504 4.68 169.42 1.794 14.134 3C 4.0 LoIntiafty _ Coninercial 343 0.65, 318 137&8 2.813 - 20.824 Subtotal _ 366 $7.71 4 59.9 Sinql Far1v 50.1. 0.594 4.68 672.00 24.910 280.332 5A 5.9 Shds Fa3v 531 0.594 4.68 33099 3.505 27.612 58 8.62 SInets Faiv 56.1 0.594 4.68 483.58 5.120 40.342 SC 2.68 StnaleFany 56.1 0.594 4.68 150.35 1.592 - 12.542 Subtotal 77.1 'IM321 33.13 230.33 Totals 107.36 1407.31 41.30 42854 * From 'Stormwatar Loading Rate Parameters for Central and South Florida, 1994. Harper Basin 4 has an e)dsling baffle box providing treatment. 3asins 4 and 5 are the existing pollutant loadings to the canals. Table 2 BMP Pollutant Removals 3MP POLLUTANT REMOVAL TABLE' BMP MP Removal Etflclenc Type __ ___ T38 TP TN iyPond 85 81 91 wa1e 80 45 25 ifeBox 80 30 0 ntstTr(aratedJ 73* 79 79*' nlstTrap (curb) 2*' 11" 10'*' le + !rttst1 (n). Butfis Bc 98.9 91.9 842 vPmd+leITtai(Q+Be8cX 992 94.3 98.1 n!stTrap(c)4BaffteBcat 84 37.7 -1-10 nIst Trap (q)IBal!eBox 81.1 853 1 79 Mtds BMP Pollutant Removal Calculatlonu wal.+ Inlet Tvap(g)+8atft.Box TSS - 100A8 + (10080)0.73 + (100-80-146)x0.8 = 98.9% Removal TP - 10O.45+ (I0045)c.79+ (100.45.446) a 91.9% Removal TN - 10(br26 + (100.25)x.79 = 84.2% Removal Dry Pond + lnletTrap (g)• Ball!. Box Iss - 185+ (100-85)x0J3 + (100-85-10.95)xO.8 99.2% Removal TP - 1000.61 + (100-81)&79 + (100.61-30.8)L3 = 94.3% Removal TN - 100x.91 + (100-91)xJ9 = 98.1% Removal riM Trp (c) + Baffle Box TSS - 100-02 + (10020)x0.8 = 84% Removal TP-10tht0.11+(1O0-1137.7% Removal TN - 100x.10 = 10% Removal Met Trap (g) + BaBa Box TSS - 1004J3 + (100-73)0.30 = 31.1% Removal TP - 1COxo.79 + (100-19)x0.3 = 35.3% Removal TN - 100x.79= 79% Removal All removal values are from 'Guide For Best Management Practice From Creech Engineers study "Pollutant Removal Testing For a Suntree Technologies Grate Inlet Skimmer 8ox', 2001 From visual observation by Brevard County staff Table 3 2psed PoIllutt Loading Baaln - 8NP Type BLIP Remov EMcINCy From Now BLIPs j - _ POUUIII* Load Rsducllon From BMjkglye.r) Proposed Pollidant Loading (kyeai) 71$ IP TN 73$ I TS$ TP TN swas+bih+ba6teb0X 989 91.9 84.2 69.30 OTT 0.03 1.56 --- +b6sb 98.9 91.9 812 8.84 T 010 000 0.19 *v -+ (a+ b8sbek 912 j 5.11 005 0.00 042 1 .--- cypd+h01b30(0+b4IISb 912 913 06.1 10.91 001 1.82 009 000 OW 35 912 913 08.1 19.83 0.11 2.70 010 ofll 0.05 4g53(Q1+bbOZ 919 919 84.2 1481 0.08 1.77 1 0.18 0.01 0.33 913 00.1 5.01 j 071 0.05 0.00 0.02 . voond • W b86 (a)+ bOle bce 962 913 00.1 &73 00 135 0.08 000 OAS ....I_ wOs+1V86(+bOleboX 20.9 91.9 KI 0.60 0.07 0.01 0.00 aftboo 3 79 4!L.OM 00 1.15 I 001 0.18 IIIIm05 . b4lebce GM 813 79 3.84 I 0.62 0.48 0.82 0.00 !iI V. kiMfth.bOlsbce 11.1 88.3 .71 2.10 0.01 0.29 0.43 0.00 008 3A kh(+bOVlIbce j j 91.04 1.1110 35.32 0.19 fl 30 k05+bOlsbck 81.1 813 71 137A0 1.53 11.17 32.02 0.35 2.97 y xn4. kiW53 (01+ b0lebce *2 1367.53 35.43 11.03 0.15 OAO _i_. (a• bOle bce 81.1 .i 1 .25 321.40 127.01 3.05 SLVI 5A W(c.bOlsbce 84 37 10 1.30 2.70 52.91 2.21 2185 81 t 4 bOO. bce J 40$ 77.37 3.23 AW - kImV(c).bOlebce 37 10 ga-MT-r il 1.35 2400 1.00 11.29 35t03 107.11 4.34 87.01 Table 4 Net Pollutant Removals TSS (kg1yr) TI' (kglyr) TN( r) Predevelopment 3015.78 35.13 380.83 Postdevelopment 630.97 21.95 . 289.15 Net Reduction 2384.81 (79%) 13.18 (37.52%) 91.68(24.01%) Summary The days of solving flooding pro b!eins in communities with simple ditch and pipe solutions have disappeared. Environmental concerns tow dictate that stoirnvater reatrnent techniques e iiiterated into these flood relief projects. By adding water quality components to water quaptity projects, communities can help achieve pollution remediation goals being established thr NPDES, Th4D1, and PLRG programs. Retrofitting existing storinwater systems to provide water quality treatment is more complicated, expeaive, and time consuming than traditional stormwater designs for new development The scarcity of available land and numerous existing utilities in older built out areas will tax an engineer's imagination to provide innovative BMPs in these locations. An carefidly planned treatment train was designed consisting of swales, ponds, hernia, baffle boxes, and inlet traps to provide overall stounwater pollution reduction. In order to address stonmwater pollution concerns, treatment mitigation was designed in offeite drainage bssha. The pollutant loadings and removals were calculated using a simple but ectiva spreadsheet analysis incorporating the latest in BMP efficiency studies. Wbile complicated dormwatcr modeling software can be used for pollutant anilysis, this type of modeling is more cost effective on large basin studies than small basins and individual projects. The poflutcml removal calculations showed an annual net reduction of 19% for TSS, 37% for Total Phosphorus, and 249A for Total Nitrogen in the Oak Street basin despite the creation of a new stormdrain system for a landlocked area. As this project demonstrates, there are typically awnerous stakeholders that need to be brought into the project early In the process and kept In tlz process throughout the life of the project. Many meetings were held with city, county, and state officials, homeowners associations, schools, soccer clubs, churches, and utility companies. Al it takes is one uncooperative stakeholder to set back or. kill a project, as was demonstrated with the church backing out of the land acquisition process after a=W verbal Indications of approvaL Using creative partnerships with other eiitites and agencies allowed the development of a unique strategy to solve flooding at several locations in the project area. References ASCE- "Guide For Best Management Practice Selection in Urban Developed Areas", 2001 Gordon England, P.E "Pollutant Removal Testing For a Suntrec Technologies Grate Inlet Skimmer Box', 2001 Harvey Harper, Ph. D, PB., "Stormwat3r Loading Rate Parameters for Central and South Florida", 1994