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CT 08-09; HIGHLAND JAMES; STORM WATER MANAGEMENT PLAN; 2008-06-16
professional land surveying civil engineering • water resources 1 1 STORM WATER MANAGEMENT 1 PLAN. I FOR I Alemeda Family Trust Carlsbad, CA. 1 PROJECT: I Highland James TM CT-XXXX I APN 207-130-37, -68 . Carlsbad, CA i • June 16, 2008 uVI 4/ Exp. 6/30/10 I. H RECEIVED I • AUG 25 2008 CITY OF CARLSBAD I PLANNING DEPT. U I . . P.C. Box 2993, Fe//brook, CA 92088 ' Tel: 760.728.4406 + Fax: 750.728.2604 Licensed in: CA + AZ CO f-mail.-project@terra-data.org Highland James Subdivision Storm Water Management Plan TABLE OF CONTENTS DESCRIPTION OF PROPOSED PROJECT Vicinity Map, Site Plan APPLICABLE LAWS, REGULATIONS, POLICIES AND REQUIREMENTS POTENTIAL EFFECTS TO WATER QUALITY ENVIRONMENTS POLLUTANTS OF CONCERN MITIGATION MEASURES TO PROTECT WATER QUALITY BEST MANAGEMENT PRACTICES (BMPs) Priority Project Category BMPs 5.1 Construction BMPs 5.2 Post-Construction BMPs 5.2.1 Site Design BMPs 5.2.2 Source Control BMPs 5.2.3 Treatment Control BMPs OPERATION & MAINTENANCE OF BMPs Cost Analysis of BMP Implementation and Maintenance SUMMARY/CONCLUSIONS ATTACHMENT LISTING Hydrology Report Specification for Storm Vegetated Swales & Underground Pipe Storage System "NPDES Permit "Lite" for Non-technical Readers" "General Categories for Water Pollution" "Non-point Source Pollution: The Nation's Largest Water Quality Problem" Resources and References Employer Training Log Best Management Practices, CASQA Storm Water Quality Handbook, 2003 SD-10 "Site Design & Landscape Planning" SD-12 "Efficient Irrigation" SD-13 "Storm Drain Signage" SD-32 "Trash Storage Areas" REFERENCES Stormwater Standards Manual, Ordinance No. 9426 (N.S.) Hydrology Manual, County of San Diego City of Carlsbad's SUSMP 2 I i I I I I I I I I I I I I I I I I I I I I • DESCRIPTION OF PROPOSED PROJECT Project Location: The site, totally approximately 1 acre, is situated on the east side of I Highland Drive just south of Tamarack Avenue. A Vicinity Map and a Site Plan are attached for review on the following pages. I Project Description: The project site is currently occupied by one single family residence with a detached garage. I The proposed project will develop divide the 2 existing parcels into 5 lots. Two existing public streets, Highland Drive and James Drive will serve the new parcels. The individual lots shall be served by public water and sewer facilities. The residential I structures shall be wood framed construction with concrete floor slabs on graded building pads. A Vicinity Map is attached for review on the following pages. Physical Features: The site is an existed graded pad with topography that slopes in the northwesterly direction with mild slope gradients. The development will not alter the existing drainage patterns from the existing pre-development condition. All drainage flows shall be collected via ribbons gutters and catch basins. Then transported via piping, and then detained in an underground storage system and outlet at existing flow levels. Surrounding Land Use: The majority of the adjacent properties are developed residential. Project Land Use: The subject application will use the existing residential designation. No land use or zoning change is required for approval of this project. Hydrologic Unit: This project is located within Carlsbad Watershed and the Hydrologic Area numbered 904.21, in the Buena Vista Creek Subarea. The Carlsbad Hydrologic unit is approximately 210 square miles. This project is a minute portion of this hydrologic area at less than 0.0000003% of the total area. A Hydrology Report is included as Attachment "A". I I I 3 I 1 I I I I I I I I I I 1 I I 1 I I I I I I I I I I I I VICINITY MAP CITY OF OCEANSIDE HIGHWAYL AVEASSWOOD - - - rri 4 ' (- .7 \ 0 '\ \ \ \ \ 3 [ITY OF VISTA \\ \ ------'-1 \\ \ \ \ SITE c:S3 \\ \- \ \ \ \ PACIFIC \ \ \ $ \ ' \ OCEAN \ M.O AiRPcR VICINITY M MW 10 WAM 4 TIT T _U11 GHLAND —JAMES C Im- AvAv " A404 EX. ASPH I Ii I LC) II L)LJJ fL EA. CTC Ln Co 1 cDc I I SEE NOTE REFERENCE I I LOT 'A' ON JAMES DRIVE ---H--Tii _-GRS-r_SCTlON BELOW I P '{ O) I I ir J/( Ar I i (• /- I I I I I I © I 1 \ IC) \ 1I > I i \ I e'J7.> \ II 1kiA A I / STORM WATER MANAGEMENT PLAN (SWMP) NOTES TREATMENT CONTROL BMPS — GRASS LINED S WALE PER DETAIL 11 A' THIS SHEET ii EX. ASPH N \- '5\4" 21.8' I I I I I I UAPIN A VE1 I H ----Hc 'r----i Ei=.i4/' i! EX. CONC w "o SOURCE CONTROL BMPS C~- UNDERGROUND PIPE STORAGE SYSTEM -kl"-Yo ti .? / I / T PLAN A4 / -\r k 7.3) 7/ N NA G E WATER SCALE: 1"=20' CITY OF OCEANSIDE HIGH WAYj. 78 SYMBOL LEGEND nrrRIPTICThI SYMBC ELEVATION, TOP OF STRUCTURE —TO[ ELEVATION, TOP OF WALL ________TW ELEVATION, TOP OF CURB ________TC ELEVATION, FINISH FLOOR ________FF ELEVATION, FINISH SURFACE FS ELEVATION, FINISH GRADE FG ELEVATION, TOP OF GRATE TG ELEVATION, HIGH POINT ________HP ELEVATION, LOW POINT ________LP ELEVATION, FLOW LINE ________FL A5SWUUU AVL. PROPOSED LOT 5 10' PRIVATE DRAINAGE I JAMES DRIVE EASEMENT GRASS DR TURF LINED OPTION OVER LAN]JLOK TURF REINFORCEMENT (CITY OF VISTA - - &V0 S WALE NO SCALE NOTES: PLACE 3 ANCHORS PER SQUARE YARD OF MATERIAL FOR GRASS DR TURF OPTION, INSTALL LANDLOK TRM 450 TURF REINFORCEMENT MAT. \DETAIL: DETENTION PIPE CC — / scr HORZ. / VERT 1 = 10' \'1L.HNI I T IY!/-\r NOT TO SCALE 20 0 20 40 Scale: 1" = 20' CIVIL ENGINEERING * LAND PLANNIN G Engineering In c. 1843 Campesino Place Oceanside, CA 92054 Tele: (760) 439-2802 Fax: (760) 439-2866 Ii) PREP R D ND ERVISIEIN OF: DATE/J.JQ GARY ?.IPSKA RCE 23080 EXPIRES 12/31/09 PLOT DATE: 6-19-08 I-- 2. APPLICABLE LAWS, REGULATIONS, POLICIES AND REQUIREMENTS The Stormwater Management Plan (SWMP) is required under the the City of Carlsbad's SUSMP. The purpose of this SWMP is to address the water quality impacts I from the proposed improvements on the Highland-James Subdivision project. Best Management Practices (BMPs) will be utilized to provide a long-term solution to water U quality. The SWMP is also intended to ensure the effectiveness of the BMPs through proper maintenance that is based on long-term fiscal planning. The SWMP is subject to revisions as needed by the engineer. I BENEFICIAL USES I The beneficial uses for the hydrologic unit are included in Tables 2.1 and 2.2. These tables have been extracted from the Water Quality Control Plan for the San Diego Basin. I MUN - Municipal and Domestic Supply: Includes uses of water for community, military, or individual water supply systems including, but not limited to, drinking water supply. I AGR - Agricultural Supply: Includes uses of water for farming, horticulture, or ranching including but not limited to, irrigation, stock, watering, or support of vegetation for range i grazing. IND - Industrial Services Supply: Includes uses of water for industrial activities that do I not depend primarily on water quality including, but not limited to, mining, cooling water supply, hydraulic conveyance, gravel washing, fire protection, or oil-well re- pressurization. I REC1 - Contact Recreation: Includes uses of water for recreational activities involving body contact with water, where ingestion of water is reasonably possible. These uses I include, but are not limited to, swimming, wading, water skiing, skin and SCUBA diving, surfing, white water activities, fishing, or us of natural hot springs. I REC2 - Non-Contact Recreation: Includes the uses of water for recreational involving proximity to water, but not normally involving body contact with water, where ingestion of water is reasonably possible. These uses include, but are not limited to picnicking, I sunbathing, hiking, camping, boating, tide pool and marine life study, hunting, sightseeing, or aesthetic enjoyment in conjunction with the above activities. I WARM - Warm Freshwater Habitat: Includes uses of water that support warm water ecosystems including, but not limited to, preservation or enhancement or aquatic habitats, vegetation, fish or wildlife, including invertebrates. COLD - Cold Freshwater Habitat: Includes uses of water that support cold water ecosystems including, but not limited to, preservation or enhancement of aquatic habitats, vegetation, fish, or wildlife, including invertebrates. WILD - Wildlife Habitat: Includes uses of water that support terrestrial ecosystems 5 I I U I I including, but not limited to, preservation and enhancement or terrestrial habitats, I vegetation, wildlife, (e.g. mammals, birds, reptiles, amphibians, invertebrates), or wildlife water and food sources. I RARE - Rare, Threatened or Endangered Species: Habitats necessary, at least in part, for the survival and successful maintenance of plant and animal species established I . under state or federal law as rare, threatened, or endangered. INLAND SURFACES WATERS I Inland Surfaces waters have the following beneficial uses as shown on Table 2.1 Table 2.1 Beneficial uses for Inland Surfaces Waters Hydrologic Unit MUN AGR IND Hydro REC1 REC2 WARM RARE WILD Number 904.21 X X X X X X X X X GROUNDWATER Groundwater beneficial uses includes agricultural and potentially municipal and industrial, none or these beneficial uses will be impaired or diminish due to the construction and operation of this project. Table 2.2 Beneficial Uses for Groundwater Hydrologic Unit MUN AGR IND Number 904.21 X X X * Excepted from Municipal I x Existing Beneficial Use 0 Potential Beneficial Use I I I I I L I I I r I El I I-- 3. CHARACTERIZATION OF PROJECT RUNOFF According to the California 2002 303d list published by the San Diego Regional Water Quality Control Board; the Pacific Ocean at the mouth of the Buena Vista Lagoon is an I impaired water body within the Carlsbad Watershed. The project location and watersheds have been compared to the current I . published 303d list of impaired water bodies and the nearest impaired water bodies are the Pacific Ocean at the Buena Vista Lagoon, impaired by I bacteria indicators generated by non-point/point source pollution. Education materials including in this SWMP in the Attachments will be distributed by the project owners and will limit pollution by limiting exposure of I these pollutants to the storm water runoff. ' EXPECTED DISCHARGES There are no sampling data available for the existing site condition. In addition, the project is I not expected to generate significant amounts of non-visible pollutants. However, the following constituents are commonly found on similar developments and could affect water quality: - Sediment discharge due to construction activities and post-construction areas left bare. - Nutrients from fertilizers - Hydrocarbons from paved areas. - Pesticides from landscaping use. Table 3.1 Pre and Post Development Runoff Q100 (cfs) 0100 (cfs) Q100 (cfs) Q100 (cfs) Basin Existing Post before Post - Const. Change Det. After detention Pre- Post A 1.1 1.6 1.1 0.0 The calculated difference between the pre- and post- development Q100 will be zero. A Hydrology Report is included as Attachment "A" that provides detailed calculations of these quantities. The increase impervious surface area will be mitigated by Vegetated swales and a piping system that will provide storage and treatment so that the overall outflow after development is equal to the pre-development flow. Specifications for this Treatment BMP are located in Attachment "B" Locations of the BMP are shown in the Site Plan (page 5) - attached. See Section 5.2.3. for description and sizing of these Treatment Control BMPs I 4. POLLUTANTS/CONSTITUENTS OF CONCERN The project locations and watersheds have been compared to the current published 303d list I of impaired water bodies. The Agua Hedionda, Buena Vista and San Elijo Lagoons are experiencing impairments to beneficial uses due to excessive coliform bacteria, sediment as 7 I I I I I I I ' well as trace metal and toxics from upstream sources. These coastal lagoons represent critical regional resources that provide freshwater and estuarine habitats for numerous plant and animal species. I None of these lagoons are downstream of this project and therefore will not contribute to the pollutants of concern. The Buena Vista Lagoon and Buena Vista creek are located within I 0.25 mile of the property and are impaired by coliform bacteria, Nutrients, and Sediment. The primary constituents of concern are then coliform, nutrients, and sediment. I The sources and activities contributing to the impairments in this area are Urban runoff, agricultural runoff, sewage spills, and livestock / domestic animals. Coliform bacteria is I generated by fecal material from human and animal waste released in sewage spills. This project is not likely to produce this constituent of concern. The Secondary Pollutants of I concern are trace minerals and toxins. Possible pollutants found on this site may include: Wash down water from Asphalt Hydrocarbons and Heavy Metals from pavement surfaces Sediment from Construction Activities The following section will outline the Best Management Practices that will provide for the protection of the water quality, with respect to the Possible pollutants of concern that are generated by this project. I 5. MITIGATION MEASURES TO PROTECT WATER QUALITY BEST MANAGEMENT PRACTICES (BMP) According to the City of Carlsbad's Applicability Checklist, Commercial Development, Restaurants, and Parking lots having more than 5000 s.f. of impervious surface are considered "priority projects" and therefore have certain storm water mitigation design requirements. Best Management Practices (BMPs) are intended to provide measures which minimize or I eliminate the introduction of pollutants into the storm water system. All constituents of concern will be removed from the storm water runoff as to minimize impact of development I on impaired water bodies. (Site Design) Non- Structural BMPs which are economical, practical small scale I measures to minimize pollutant runoff are to be constructed on existing developments as appropriate. Source Control (Non-structural) BMPs include education, clean-up and facility maintenance to prevent pollutants form entering the storm water system. Treatment Control BMPs are facilities designed to remove pollutants of concern from the storm water conveyance system to the maximum extent practicable through the incorporation of treatment control BMPs. The following is a list of suggested BMP's for this project Post-Construction BMPs Post-Development anticipated pollutants from this project are listed in Table 5.1 Table 5.1 Project Sed Nutrients Hvy Org Trash Oxy Oil & Bact & Pesticides Category Met Comp & Deb Dem Grease Virus Detached X X X X X X X Residential Development I x = anticipated P = Potential A potential pollutant if landscaping exists on-site A potential pollutant if the project includes landscaping. I (3) A potential pollutant if land use involves food or animal waste products. Including petroleum hydrocarbons. Including solvents 5.1 Construction BMPs I To address water quality for the project, BMPs will be implemented during construction and post-construction. The construction activities are dually regulated by the California State wide I General Construction Permit and San Diego County Ordinances. A grading and erosion control plan will be processed through the City of Carlsbad. Erosion Control must be incorporated per City Standards. Gravel Bag Barrier Material Spill Prevention and Control Spill Prevention and Control Concrete Waste Management Water Conservation Practices Gravel Bag Berm Material Delivery and Storage Stockpile Management Solid Waste Management Stabilized Construction Entrance/Exit Vehicle and Equipment Maintenance Dust Controls Permanent re-vegetation of all disturbed areas Scheduling to reduce Erosion of Wind, Rain Runoff - 5.2 Post-Construction BMPs I 1 9 Li I I F I I I 5.2.1. Site Design BMPs This project was designed to minimize, to the maximum extent practical, the introduction of I pollutants and conditions of concern that may result in significant impacts to the storm water conveyance system. Site Design BMPs are designed to maintain pre-development runoff characteristics. The following concepts were applied to this project in the following manner: 1) Minimize impervious footprint 1) Increase building density I 2) construct streets, sidewalks, and parking aisles to the minimum widths necessary, provided that public safety and walkable environment for pedestrians are not compromised; and I 3) minimize the use of impervious surfaces, such as decorative concrete, in the landscape design. I The prolect has been designed with maximize density on the 1 acre site. There will be no increase in impervious road surface as there are no improvements required. All new parcels will take access over existing roadways. Driveways will be designed to minimum standards as to minimize the impervious surface. 2) Conserve natural area. I 1) Concentrate or cluster development on the least environmentally sensitive portions of a site while leaving the remaining land in a natural undisturbed condition. I 2) Use natural drainage systems to the maximum extent practicable. There is no sensitive area on the site. Part of the site has been previously developed. I Vegetative swales and natural drainage patterns will be used in the drainage design. 3) Minimize directly connected Impervious Areas (DClAs). I Landscape areas can be used to provide infiltration and therefore minimizing DClAs. 4) Maximize canopy interception and water conservation. I 1) Preserve existing native trees and shrubs; and 2) Plant additional native or drought tolerant trees and large shrubs in place on non- drought tolerant exotics. Landscape plan calls for native tree and shrubs. 5) Convey runoff safely from the tops of slopes. I There are no significant slopes on this proiect. 6) Vegetate slopes with native or drought tolerant vegetation. I There are no significant slopes on this proiect. 7) Stabilize permanent channel crossings. I 10 I Not-applicable - No channel crossings. 8) Install energy dissipaters, such as rip-rap, at the outlets of new storm drains, culverts, I conduits, or channels that enter unlined channels in accordance with applicable specifications to minimize impacts to receiving waters. This proiect will drain eventually drain to paved surfaces will not need energy dissipaters. I 5.2.3. Treatment Control (Structural) BMPs I There will be one Treatment Control BMP used for this project, the Vegetated Swale. Roof Tops I Numeric Sizing for Volume Based Treatment control BMPs: I V= A a C P V = required treatment volume of Swales A = Per lot area of impervious area 3000 s.f. I P = Precipitation = 0.70" = 0.058' I V=3000X1 I These water quality calculations show that at this volume, there is enough area to provide Bioswales and a Underground Pipe Storage System for this project. As many roof drains as possible will be outlet to Landscape Filtration Areas, therefore providing filtration of roof top sediment. Lot runoff will be directed to Vegetated Swales that will provide infiltration as well as controlled conveyance to the Underground Pipe Storage Systems. By detaining the increased runoff and then outleting this runoff to the existing storm drain system at the existing flow rate, the increase runoff will be mitigated to I the maximum extent practicable. Other methods of Treatment BMPs were considered. Other methods such as drainage inserts and hydrodynamic separators were considered but do not provide high enough I removal rates for the pollutants on concern necessary for this project. I The biofiltration swales planned for this project provide known medium to high removal rates for the sediment, heavy metals, trash & debris, bacteria and oil and grease removals making these appropriate Treatment Control BMPs for this project. I Calculations of this Volume are calculated by Basin and are included in the "Hydrology Report" (Attachment "A"). The Underground Pipe Storage System will store and treat this I volume and outlet the treated storm water runoff at pre-development levels. See Attachment "B" for specifications of this Treatment BMPs. Further investigation into this design will be done as the drainage and grading are in the final phase. I 1 11 Pnst-nnstrLmtinn RMPs Preventative Maintenance and Routine Inspection Type of BMP: Landscape Filtration Swales (Bioswale) (Ti) Routine Action Visual Inspection Maintenance Indicator Accumulation of silt and debris. Signs of erosion. Field Measurement Excessive foliage and grass height Measurement Frequency Inspect system weekly during rainy season Maintenance Activity Remove debris and maintain landscaping Type of BMP: Underground Pipe Detention System (Si) Routine Action Visual Inspection Maintenance Indicator Accumulation of silt and debris. Signs of erosion. Field Measurement Excessive foliage and grass height Measurement Frequency Inspect system weekly during rainy season Maintenance Activity Remove debris and maintain landscaping I The maintenance of post-construction BMPs will be the responsibility of the Owner of the project. The average annual cost for maintaining the Vegetated Swales and Underground Pipe Storage System associated with this project will be approximately $2500/year. I I I I I I I El I I I I I I I I I Operation & Maintenance Program The operational and maintenance needs of a Bioswales. I Vegetation management to maintain adequate hydraulic functioning and to limit habitat for disease-carrying animals. I - Animal and vector control. - Periodic sediment removal to optimize performance. - Trash, debris, grass trimmings, tree pruning, and leaf collection and removal to I prevent obstruction of a Swale and monitoring equipment. - Removal of standing water, which may contribute to the development of aquatic plant communities or mosquito breeding areas. I - Removal of graffiti. - Preventive maintenance on sampling, flow measurement, and associated BMP equipment and structures. I - Erosion and structural maintenance to prevent the loss of soil and maintain the performance of the Swale. Inspection Frequency I The facility will be inspected and inspection visits will be completely documented: - Once a month at a minimum. - After every large storm (after every storm monitored or those storms with more I than 0.50 inch of precipitation.) - On a weekly basis during extended periods of wet weather. I Aesthetic and Functional Maintenance Aesthetic maintenance is important for public acceptance of stormwater facilities. I Functional maintenance is important for performance and safety reasons. Both forms of maintenance will be combined into an overall Stormwater Management I System Maintenance. Aesthetic Maintenance I The following activities will be included in the aesthetic maintenance program: I Graffiti Removal. Graffiti will be removed in a timely manner to improve the appearance of a Swale & Detention Basin and to discourage additional graffiti or other acts of vandalism. I Grass Trimming. Trimming of grass will be done on the Swale, around fences, at the inlet and outlet structures, and sampling structures. I Weed Control. Weeds will be removed through mechanical means. Herbicide will not be used because these chemicals may impact the water quality monitoring. I [ 1 Functional Maintenance I Functional maintenance has two components: Preventive maintenance Corrective maintenance I 1) Preventive Maintenance Preventive maintenance activities to be instituted at a Swale are: I a) Grass Mowing. Vegetation seed mix within the Swale designed to be kept short to maintain adequate hydraulic functioning and to limit the development of faunal habitats. I b) Trash and Debris. During each inspection and maintenance visit to the site, debris and trash removal will be conducted to reduce the potential for inlet and outlet structures and other components from becoming clogged and inoperable during I storm events. Sediment Removal. Sediment accumulation, as part of the operation and maintenance program at a Swale, will be monitored once a month during the dry I season, after every large storm (0.50 inch), and monthly during the wet season. Specifically, if sediment reaches a level at or near plant height, or could interfere with flow or operation, the sediment will be removed. If accumulation of debris or I sediment is determined to be the cause of decline in design performance, prompt action (i.e., within ten working days) will be taken to restore the Swale to design performance standards. Actions will include using additional fill and vegetation I and/or removing accumulated sediment to correct channeling or ponding. Characterization and Appropriate disposal of sediment will comply with applicable local, county, state, or federal requirements. The Swale will be regraded, if the flow I gradient has changed, and then replanted with sod. Removal of Standing Water. Standing water must be removed if it contributes to the development of aquatic plant communities or mosquito breeding areas. e) Mechanical and Electronic Components. Regularly scheduled maintenance will be performed on fences, gates, locks, and sampling and monitoring equipment in accordance I with the manufacturers' recommendations. Electronic and mechanical components will be operated during each maintenance inspection to assure continued performance. I f) Fertilization and Irrigation. The vegetation seed mix has been designed so that fertilization and irrigation is not necessary. Fertilizers and irrigation will not be used to maintain the vegetation. Elimination of Mosquito Breeding Habitats. The most effective mosquito control program is one that eliminates potential breeding habitats. I I Corrective Maintenance Corrective maintenance is required on an emergency or non-routine basis to correct I problems and to restore the intended operation and safe function of a Swale. Corrective maintenance activities include: I - Removal of Debris and Sediment. Sediment, debris, and trash, which impede the hydraulic functioning of a Swale and prevent vegetative growth, will be removed I and properly disposed. Temporary arrangements will be made for handling the sediments until a permanent arrangement is made. Vegetation will be reestablished after sediment removal. I - Structural Repairs. Once deemed necessary, repairs to structural components of a Swale & Detention Basin and its inlet and outlet structures will be done within 10 working days. Qualified individuals (i.e., the designers or contractors) will conduct I repairs where structural damage has occurred. - Embankment and Slope Repairs. Once deemed necessary, damage to the embankments and slopes of Swales will be repaired within 10 working days). I - Erosion Repair. Where a reseeding program has been ineffective, or where other factors have created erosive conditions (i.e., pedestrian traffic, concentrated flow, etc.), corrective steps will be taken to prevent loss of soil and any subsequent I danger to the performance of a Swale or Detention Basin. There are a number of corrective actions than can be taken. These include erosion control blankets, riprap, sodding, or reduced flow through the area. Designers or contractors will be I consulted to address erosion problems if the solution is not evident. - Fence Repair. Repair offences will be done within 30 days to maintain the security of the site. I - Elimination of Animal Burrows. Animal burrows will be filled and steps taken to remove the animals if burrowing problems continue to occur (filling and compacting). If the problem persists, vector control specialists will be consulted I regarding removal steps. This consulting is necessary as the threat of rabies in some areas may necessitate the animals being destroyed rather than relocated. If the BMP performance is affected, abatement will begin. Otherwise, abatement will I be performed annually in September. - General Facility Maintenance. In addition to the above elements of corrective maintenance, general corrective maintenance will address the overall facility and its I associated components. If corrective maintenance is being done to one component, other components will be inspected to see if maintenance is needed. I Maintenance Frequency The maintenance indicator document, included as Table 6.1, lists the schedule of I maintenance activities to be implemented at a Swale. Debris and Sediment Disposal Waste generated at Swales is ultimately the responsibility of the owner of the property. Disposal of sediment, debris, and trash will comply with I applicable local, county, state, and federal waste control programs. Hazardous Waste Suspected hazardous wastes will be analyzed to determine disposal options. Hazardous wastes generated onsite will be handled and disposed of according to applicable Ii al, state, and federal regulations. A solid or liquid waste is considered a hazardous waste if it exceeds the criteria listed in the CAR, Title 22, Article 11. I Certification of Responsibility Inspection and maintenance of BMPs is the responsibility of Owner of this project. A I contract for trash management and litter control and landscape maintenance, will be made with outside contractors, as necessary. I The future tenants will be instructed about environmental procedure regarding contamination and clean-up procedures. I All documents, including this Storm Water Management Plan, relating to site maintenance will be kept on-site and will be made available to county Inspector, upon request. I The following person is in responsible charge of education of tenants & employees, and implementation and maintenance of the required BMP's. Subsequent owners shall obtain said responsibilities. Name: TBD Telephone: TBD I I Signature Date I The Stormwater Management Plan has been prepared under the direction of the following I Registered Civil Engineer. The Registered Civil Engineer attests to the to technical information contained herein and the engineering data upon which recommendations, conclusions, and decisions are ased. ,r Dt(e CO 0 f- -C2 NO'C57860 1 0/'0 Fn CIVIL OF C I 1 16 I I F I Ii I ATTACHMENT "A I I I F I I I I I I 11 I I I HYDROLOGY REPORT u FOR I Highland James Subdivision APN: 207-130-37,-68 Carlsbad, CA 92008 ' PROJECT OWNERS Alameda Family Trust Carlsbad, CA 92008 1 I PREPARED BY: Aquaterra Engineering Inc. ' 1843 Campesino Place Oceanside, CA 92054 tele: 760-439-2802 I fax: 760-439-2866 I June 16, 2008 ;re I c3ary Lip a, RCE 2308b Date I I I I / Exp. 12/31/09 Q before 0 after detention detent. (cfs) (cfs) 1.1 before after detent. detent. (cfs) (cfs) - - - - - - - - - - - - - - - - - - - SUMMARY TABLE OF HYDROLOGY CALCULATIONS CT-XXX HIGHLAND JAMES SUBDIVISION DATE: June 16, 2008 BEFORE- POST- C Tc I A CONSTRUCTION CONSTRUCTION (mm.) ("/hr.) (acres) 0.20 7.8 4.94 1.06 BASIN A 0.48 10.6 4.06 0.99 0.50 0.0 Hydrology & Hydraulics Report City of Carlsbad This Hydraulics and Hydrology Report was prepared using the following Manuals: Hydrology Manual, June 2003 edition, County of San Diego Drainage of Highway Pavements, U.S. Dept. of Transportation The Rational Method was used to determine the 100 yr. storm Q values. The Rational Method uses the following formula to establish the flow: Q=CIA where, Q = the peak runoff in cubic feet per second C = Runoff coefficient representing the ratio of runoff to rainfall = time average intensity in inches per hour A = Area of the subbasin in acres Project Description The 1.1 ± acre project site is occupied by one single family dwelling and detached garage . The surrounding adjacent lands have been developed with single family structures on standard sized residential lots. The proposed project is to subdivide the site into 5 lot for future residential development. Two of the proposed lots will take access from Highland Drive a public street; the other three lots will frount on James Drive, also publicly maintained. The existing site topography slopes in the easterly direction with a 20' ± high steep slope within the site interior. All drainage flows shall be collected and transported to offsite public drainage facilities by surface swales and underground drainage structures and pipes As a result of the proposed construction of the structures and paved surfaces, the calculated 100 year frequency storm water volumes will be increased by 0.5 cfs for Basin "A". This increased peak discharge flow shall be mitigated with the use of a underground pipe detention basin. The detention basin has been numerically sized based on the increase of impervious surface in the post development condition. The storm water discharge from the detention basin is equal to the discharge under the pie-construction condition There is no historical evidence that the downstream water courses are inadequate to handle the storm flows. The site development will not adversely impact downstream properties or drainage systems The project site is not located near a floodway or floodplain or a water course plotted on any official floodway map. Conclusion As a result of the project layout and the inclusion of design features, we do not anticipate any negative impacts to downstream properties. I I I I H I LI I I I I I I I I I I H I I I HYDROLOGY REPORT I U U I I I I I LI I I I I I I U I I I Aqua terra Engineering Inca I I U I I I I t- I I I L I I t- I Aquaterra Engineering inc. PROJECT A:2i 6)4"'2 DATE: 3/JJti ' I I , I I I I I I I I I I I I I San Diego County Hydrology Manual Data: June 2003 Section: 3 Page: 12of26 Note that the Initial Time of Concentration should be reflective of the ge n e r a l l a n d - u s e a t t h e upstream end of a drainage basin.. A single lot with an area of two or l e s s a c r e s d o e s n o t h a v e a significant effect where the drainage basin area is 20 to 600 acres. Table 3-2 provides limits of the length (Maximum Length (L M)) of sheet flow to be. used in hydrology studies. Initial T1 values based on average C values the Land Use Element are also included. These values can be used in planning and design a p p l i c a t i o n s a s d e s c r i b e d below. Exceptions may be approved by the "Regulating Agency" when submitted with a - detailed study. Table 3-2 FI:4 i (S) irr F)V1 o[P : LAJti I Element* Acre DU/.5% 1% 2% 3% 5% 10% LM T j Ti LM Ti LM 10,9.1-100- I Ti I.A ITiLM T. Natural 50 13.2 70 12.5 85 8.7 1006.9 LDR . 1 . 50 12.2 70 11.5 85 10.0 100 9.5 100 8.0 100 6.4 LDR 2 50 11.3 70 10.5 85 9.2 100 .10.3100 8.81 100 7.4 100 5.8 LDR 2.9 50 10.7 70 10.0 85 8.8 95 8.1 100 7.0 100 5.6 MDR 4.3 50 10.2 70 9.6 80 8.1 95 7.8 100 6.7 100 .5.3 MDR 7.3 50 9.2 65 8.4 80 7.4 95 7.0 100 6.0 100 4.8 MDR 10.9 50 8.7 65 7.9 80 6.9 90 6.4 100 5.7 100 4.5 MDR 14.5 50 8.2 65 7.4 80 6.5 90 6.0 100 5.4 100 4.3 HDR 24 50 67 65 6.1 75 5.1 90 4.9 95 43 1001 3.5 RDR 43 50 5.3 65 4.7 75 4.0 85 3.8 95 3.4 10012.7 N. Corn 50 5.3 60 4.5 75 4.0 85 3.8 95 3.4 100 2.7 G. Corn 50 4.7 60 4.1 75 3.6 85 3.4 90 2.9 100 2.4 O.PJCorn 50 4.2 60 3.7 70 3.1 80 2.9 90 2.6 100 2.2 Limited I. 50 4.2 60 3.7 70 3.1 80 2.9 90 2.6 100 2.2 50 3.7 60 3.2 70 2.7 80 2.6 90 2.3 100 1.9 . *.See Table 3-1 for more detailed description 3-11 San Diego County Hydrology Manual Section: 3 Date: June 2003 Page: 6 of 26 Table 3-1 RUNOFF COEFFICIENTS FOR URBAN AREAS Soil Type - Undisturbed Natural Terrain (Natural) Permanent Open Space Low Density Residential (LD ) Resident4 1.0 DU/A or less Low Density Residential (LDR) Residential, 2.0 DU/A or less Low Density Residential (LDR) Residential, 2.9 DU/A or less Mediump ' Medium Density Residential (MDR) Residential, 7.3 DU/A or less Medium Density Residential (MDR.) Residential, 10.9 DU/A or less Medium Density Residential (MDR) Residential, 14.5 DU/A or less High Density Residential (HDR) Residential, 24.0 DU/A or less High Density Residential (HDR.) Residential, 43.0 DU/A or less Commercial/Industrial (N. Corn) Neighborhood Commercial Commercial/Industrial (G. Corn) General Commercial Commercial/Industrial (O.P. Corn) Office Professional/Commercial Commercial/Industrial (Limited I.) Limited Industrial Commercial/Industrial (General 1.) General Industrial *The values associated with 0% impervious may be used for direct calculation of tl coefficient, Cp, for the soil type), or for areas that will remain undisturbed in perpetuit is located in Cleveland National Forest). DU/A dwelling units per acre NRCS = National Resources Conservation Service 0* 0.20 0.25 , 0.30 0.35 10 0,32 0.36 0.41 20 0.34 0.38 0,42 0.46 25 0.38 0.41 0.45 0.49 30 0.45 0.48 0.52 40 0.48 0.51 0.54 0.57 45 0,52 0.54 0.57 0.60 50 0.55 0.58 0.60 0.63 65 0.66 0.67 0.69 0.71 80 0.76 0.77 018 0.79 80 0.76 0.77 0.78 0.79 85 0.80 0.80 0,81 0.82 90 0.83 0.84 0.84 0.85 90 0.83 0.84 0.84 0.85 95 0.87 0.87 0.87 0.87 e iunoff coefficient as described in Section 3.1.2 (representing the pervious runoff y. Justification must be given that the area will remain natural forever (e.g., the area 3-6 I I ________________ I = Intensity (In/hr) __________Illiftil _IIiIllllI iIl liii t i i ht!III I I I I tjj'Ilh;qII Jill 11; D a Duratio1 oil IllhIllhIlIIIlUIIllIilhlIIIIIII Ems 1 USIuIlIII1IIIIlIIIIIII lIIIuIuIIIIIIHuhIIII IIIIIIIIIIIIIIIIIIIIIIIIIII1IIIIIIIIIIIllhIII ii I !!!IIIIIII!! liii j!!!IIIj IIIIIIIIIIIIIIIIIIIlIIIIIllhIIflhI1IIIIIIIIUIHHffluIffluii!!IIIIiIIll!llllluiillfl ns—n-a.s..uimina,a uotlutfl....uI.Ifl ,_____uo_dIuI. hull 'fl _flfllfl,fl ml hl U UI hhultluhll,IM * U OS UIUlm*lhluI I I*III —S U 511*1* I 1*111 UU••II•IiuIJiIflhJUIIflIuI.flhuHIM 11111", a U.I.UIU Ullull INIMMUNNNI'll 111111 lilt manni inglivill 11111 IM 1111 lmm m 00 manswall lit.. Z *uUsupiuiiuui. IaIIu1Iuuup I • *PUuR$I*iIII liii HHWhIMl!IIIIIüuiliIifliiiin ia aaauulIIsIuiu III lIiIuIflufliu Ulifihli iiU*UlUlllIIIulIuHIIn ç (:2D0 ; cc SbC 70 &RAfir Md Lnside- T Alc LeDZ -12 7 D E DaF .'D C'I 't\% ( (I 1 r - j+efN\r\c<\ 4° CbG bD DaE2J \ 1 '\N1E CC- 4 ic lic CHESTPJ11 \ Amic t I \\ ARL5AD fW \C ;>V3L + / • C CbD eq LvF3 -\ .pI__J. •1 Cb LeC. CbC GC Md I 's ,60 g4a 'lea ond - :- < - 1 .- CbL0 LeE Nntoo~ SAN DIEGO COUNTY SOILS INTERPRETATION STUDY - I SAN LUIS REV QUADRANGLE I •z- SHEET22 SCALE 1= 2000' \l2ii MIC — .— — — — — — — - — — — — — — — — Cou-nty of San Diego HydrologY Manual 11,1111, IT-- Ac4c ht_E1l1'iNI( \\/ , I Ramfal11SOPtUViQl8 I I I I 100 Year Rainfall Event -24 Hour 4. iOiAWA 1 .•.- \...,. . 'I t%Ad - W. 114v. im 1UP I IN r L 1 1 LI! L L — — — — — — — — — - — — — — — — — — I _l_I1 çi ij t 0 -i iego ual 01 Rainfall ISOP1101als uk t I I 11.41 1 1 '(J kA thtpu LLLtk tW4 '1 U - I --•-' •• j.I. . - ... 1• WHsfltIVIC11'" LJH .:k:J 1-44 MIles IT EQUATION AE I11.9L3 O385 I Feet Tc -5000 = Tc = lime of concentTation (hours) L = Watercourse Distance (miles) —4000 = Change in elevation along effective slope line (See Figure 35) (feet) 3000 To HoursMhiutes 2090 4 240 3 180 —1000 2 120 900 ______ 800 100 7fl0 90 _50D'\ 80 70 41ID 1 60 —300 -50 4 —290 L Was Feet 30 —100 4000 20 18 3 16 59 0.5 14 40 2000 12 1800 30 1800 10 1400 \ 1200 20 —1000 7 900 6 P1M F. 5 10 AE Callfrmia Division of Hi 5 (1941) and F200 L Ic II - FIGURE Nomograph for Deferminaflon of Time of Concenfratlon (Ic) or Travel Time (It) for Natural Ytersheds 34 I DETENTION BASIN I CALCULATIONS I I I I I I I I I I I I I I I I RATIONAL METHOD 1-IYDROGRAPH PROGRAM fPYRIGHT 1992. 2001 RICK ENGINEERING COMPANY N DATE 6/1612008 HYDROGRAPH FILE NAME Textl E OF CONCENTRATION 11 MIN. OUR RAINFALL 2.5 INCHES SIN AREA 0.99 ACRES tu NOFF COEFFICIENT 0.4 PEAK DISCHARGE 1.6 CFS IME (MIN) = 0 DISCHARGE (CFS) = 0 ME (MIN) = 11 DISCHARGE (CFS) = 0.1 TIME (MIN) = 22 DISCHARGE (CFS) = 0.1 ME (MIN) = 33 DISCHARGE (CFS) = 0.1 ME (MIN) = 44 DISCHARGE (CFS) = 0.1 ME (MIN) = 55 DISCHARGE (CFS) = 0.1 TIME (MIN) = 66 DISCHARGE (CFS) = 0.1 TIME (MIN) = 77 DISCHARGE (CFS) = 0.1 (MIN) = 88 DISCHARGE (CFS) = 0.1 I IME IME (MIN) = 99 DISCHARGE (CFS) = 0.1 IME (MIN) = 110 DISCHARGE (CFS) = 0.1 TIME (MIN) = 121 DISCHARGE (CFS) = 0.1 (MIN) = 132 DISCHARGE (CFS) = 0.1 IIME IME (MIN) = 143 DISCHARGE (CFS) = 0.1 IME (MIN) = 154 DISCHARGE (CFS) = 0.1 TIME (MIN) = 165 DISCHARGE (CFS) = 0.1 (MIN) = 176 DISCHARGE (CFS) = 0.1 O IME IME (MIN) = 187 DISCHARGE (CFS) = 0.1 IME (MIN) = 198 DISCHARGE (CFS) = 0.2 IME (MIN) = 209 DISCHARGE (CFS) = 0.2 TIME (MIN) = 220 DISCHARGE (CFS) = 0.2 (MIN) = 231 DISCHARGE (CFS) = 0.3 R IME IME (MIN) = 242 DISCHARGE (CFS) = 0.4 IME (MIN) = 253 DISCHARGE (CFS) = 1.6 TIME (MIN) = 264 DISCHARGE (CFS) = 0.2 (MIN) = 275 DISCHARGE (CFS) = 0.2 I IME IME (MIN) = 286 DISCHARGE (CFS) = 0.1 IME (MIN) = 297 DISCHARGE (CFS) = 0.1 TIME (MIN) = 308 DISCHARGE (CFS) = 0.1 TIME (MIN) = 319 DISCHARGE (CFS) = 0.1 (MIN) = 330 DISCHARGE (CFS) = 0.1 RIME IME (MIN) = 341 DISCHARGE (CFS) = 0.1 IME (MIN) = 352 DISCHARGE (CFS) = 0.1 TIME (MIN) = 363 DISCHARGE (CFS) = 0.1 IME (MIN) = 374 DISCHARGE (CFS) = 0 I' \4s\A: f. k) 3 User Name: Gary Lipska Date: 06-16-08 Project: O'gara-Carlsbad Time: 19:55:54 Scenario: BASIN-A RESERVOIR REPORT Reservoir Number: I Name: PIPE RESERVOIR [RATING CURVE LIMIT] Minimum Elevation = 128.30 (if) Maximum Elevation = 129.80 (if) Elevation Increment 0.50 (ft) [STAGE STORAGE INFORMATION] Storage Method: Underground Pipe Length = 150.00 (if) Diameter = 1.50 (ft). [DISCHARGE INFORMATION] Structure Number: 1 Type: Circular Concrete - Square Edge with Headwall Name: 6" DISCARGE PIPE [RESERVOIR STAGE STORAGE/DISCHARGE] -------------------------------------------------------------------------------- Elevation Stage Area Storage Discharge (sq if) (Cu if) (cfs) 128.30 0.00 0.00 0.00 0.00 128.80 0.50 212.13 154.69 0.63 129.30 1.00 212.13 375.45 0.94 129.80 1.50 0.00 530.14 1.17 Maximum Storage = 530.14 (Cu if) Maximum Discharge = 1.17 (cfs) Page 1 of 8 I User Name: Gary Lipska Date: 06-16-08 Project: O'gara-Carlsbad Time: 19:56:03 Scenario: BASIN-A P OUTLET STRUCTURE REPORT I Structure Number :1 Type : Circular Concrete w/ square edge w/ headwall Name :6" DISCARGE PIPE I [CULVERT STAGE VS. DISCHARGE] ------------------------------------------------------------------------------ i Elevation (ft) Stage (ft) Discharge (cfs) 128.30 0.00 0.00 P 128.80 0.50 0.63 129.30 1.00 0.94 129.80 1.50 1.17 I 130.30 2.00 1.34 130.80 2.50 1.48 131.30 3.00 1.61 131.80 3.50 1.73 I Hydrograph Number: 2 Name: BASIN-A-OUTFLOW Type: Reservoir: Storage Indication I [HYDROGRAPH INFORMATION] Peak Flow (Qp) 1.09 (cfs) I Time to Peak (Tp) = 264.00 (mm) Time of Base (Tb) = 444.00 (mm) Volume = 0.09 (ac-ft) I Time Step = 2.00 (mm) Peak Elevation = 129.63 (ft) I Detention Time = NA [RESERVOIR STRUCTURE INFORMATION] Number = 1 Name = PIPE RESERVOIR Storage Type = Underground Pipe Maximum Storage = 530.14 (cu ft) Maximum Discharge = 1.17 (cfs) [INFLOW HYDROGRAPH INFORMATION] Number = 1 Name = BASIN-A-INFLOW Peak Flow (Qp) 1.60 (cfs) Time to Peak (Tp) = 253.00 (mm) Time of Base (Tb) = 374.00 (mm) Volume = 0.09 (ac-ft) Flow Multiplier 1.00 I Page 2of 8 I I I I I U Date: 06-16-08 Time: 19:56:14 User Name: Gary Lipska Project: O'gara-Carlsbad Scenario: BASIN-A [EQUATION] 0.5(I1+I2)dt + SI-0.5(02)dt Where: II = Previous Inflow 12 = Current Inflow dt = Time increment SI = Previous Storage S2 = Current Storage 01 = Previous Outflow 02 = Current Outflow Page 3 of 8 I A=0.5(I1+I2)dt I BzS1-0.5(O1)dt C = S2 + 0.5 (02) dt FLOOD HYDROGRAPH REPORT Computation of Reservoir Outflow Table of Storage Indication Method [The time interval is 2.00 mm] Intv Time Inflow A B C Outflow Storage Elev (mm) (cfs) (cfs) (cfs) (cfs) (cfs) (Cu ft) (ft) 1 2.00 0.02 0.02 -------------------------------------------------------------------------------- 0.00 0.87 0.00 0.88 128.30 2 4.00 0.04 0.05 0.87 3.14 0.01 3.16 128.31 3 6.00 0.05 0.09 3.14 6.26 0.03 6.29 128.32 4 8.00 0.07 0.13 6.26 9.89 0.04 9.94 128.33 5 10.00 0.09 0.16 9.89 13.84 0.06 13.89 128.34 6 12.00 0.10 0.19 13.84 17.53 0.07 17.60 128.36 7 14.00 0.10 0.20 17.53 20.20 0.08 20.29 128.37 8 16.00 0.10 0.20 20.20 21.82 0.09 21.91 128.37 9 18.00 0.10 0.20 21.82 22.80 0.09 22.89 128.37 10 20.00 0.10 0.20 22.80 23.39 0.10 23.49 128.38 11 22.00 0.10 0.20 23.39 23.75 0.10 23.85 128.38 12 24.00 0.10 0.20 23.75 23.97 0.10 24.06 128.38 13 26.00 0.10 0.20 23.97 24.10 0.10 24.20 128.38 14 28.00 0.10 0.20 24.10 24.18 0.10 24.28 128.38 15 30.00 0.10 0.20 24.18 24.22 0.10 24.32 128.38 16 32.00 0.10 0.20 24.22 24.25 0.10 24.35 128.38 17 34.00 0.10 0.20 24.25 24.27 0.10 24.37 128.38 18 36.00 0.10 0.20 24.27 24.28 0.10 24.38 128.38 19 38.00 0.10 0.20 24.28 24.29 0.10 24.39 128.38 20 40.00 0.10 0.20 24.29 24.29 0.10 24.39 128.38 21 42.00 0.10 0.20 24.29 24.29 0.10 24.39 128.38 22 44.00 0.10 0.20 24.29 24.30 0.10 24.40 128.38 23 46.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 I I I I I I I I I I I User Name: Gary Lipska Date: 06-16-08 Project: O'gara-Carlsbad Time: 19:56:14 Scenario: BASIN-A --------------- Intv Time Inflow A B C Outflow Storage Elev I (mm) (cfs) (cfs) (cfs) (cfs) (cfs) (Cu ft) (ft) 24 48.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 I 25 50.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 26 52.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 27 54.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 I 28 56.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 29 58.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 I 30 31 60.00 62.00 0.10 0.10 0.20 0.20 24.30 24.30 24.30 24.30 0.10 0.10 24.40 24.40 128.38 128.38 32 64.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 I 33 34 66.00 68.00 0.10 0.10 0.20 0.20 24.30 24.30 24.30 24.30 0.10 0.10 24.40 24.40 128.38 128.38 35 70.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 36 72.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 I 37 74.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 38 76.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 39 78.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 I 40 80.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 41 82.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 42 84.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 I 43 86.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 44 88.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 45 90.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 I 46 92.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 47 94.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 48 96.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 I 49 98.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 50 100.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 51 102.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 I 52 104.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 53 106.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 54 108.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 I 55 110.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 56 112.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 57 114.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 I 58 116.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 59 118.00 0.10 0.20 24.30 24.30 0.10 24.40 12838 60 120.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 I 61 122.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 62 124.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 I 63 126.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 64 128.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 65 130.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 66 132.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 Page 4 of 8 I Page 5 of 8 I User Name: Gary Lipska Date: 06-16-08 Project: O'gara-Carlsbad Time: 19:56:14 Scenario: BASIN-A Intv Time Inflow A B C Outflow Storage Elev (mm) r (cfs) (cfs) (cfs) (cfs) (cfs) (cu ft) (ft) 67 134.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 68 136.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 69 138.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 70 140.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 71 142.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 72 144.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 73 146.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 74' 148.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 75 150.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 76 152.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 77 154.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 78 156.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 79 158.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 80 160.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 81 162.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 82 164.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 83 166.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 84 168.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 85 170.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 86 172.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 87 174.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 88 176.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 89 178.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 90 180.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 91 182.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 92 184.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 93 186.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 94 188.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 95 190.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 96 192.00 0.11 0.21 24.30 24.73 0.10 24.84 128.38 97 194.00 0.13 0.24 24.73 26.31 0.11 26.41 128.39 98 196.00 0.15 0.27 26.31 29.00 0.12 29.12 128.39 99 198.00 0.16 0.31 29.00 32.38 0.13 32.51 128.41 100 200.00 0.18 0.35 32.38 36.16 0.15 36.31 128.42 101 202.00 0.20 0.38 36.16 40.20 0.17 40.36 128.43 102 204.00 0.20 0.40 40.20 43.51 0.18 43.69 128.44 103 206.00 0.20 0.40 43.51 45.52 0.19 45.71 128.45 104 208.00 0.20 0.40 45.52 46.73 0.19 46.93 128.45 105 210.00 0.20 0.40 46.73 47.47 0.20 47.66 128.45 106 212.00 0.20 0.40 47.47 47.91 0.20 48.11 128.46 107 214.00 0.20 0.40 47.91 48.18 0.20 48.38 128.46 108 216.00 0.20 0.40 48.18 48.35 0.20 48.55 128.46 109 218.00 0.20 0.40 48.35 48.44 0.20 48.64 128.46 I I I I I I I I I I I I I I I I I I I User Name: Gary Lipska Date: 06-16-08 Project: O'gara-Carlsbad Time: 19:56:14 Scenario: BASIN-A --------------------------------------------------------------------------- Intv Time Inflow A B C Outflow Storage Elev I (mm) (cfs) (cfs) (cfs) (cfs) (cfs) (cu ft) (ft) 110 220.00 0.20 0.40 ------------------------------------------------------------------------------ 48.44 48.50 0.20 48.70 128.46 111 222.00 0.20 0.40 48.50 48.54 0.20 48.74 128.46 112 224.00 0.20 0.40 48.54 48.56 0.20 48.76 128.46 113 226.00 0.22 0.42 48.56 49.45 0.20 49.65 128.46 U 114 228.00 0.24 0.45 49.45 51.73 0.21 51.94 128.47 115 230.00 0.25 0.49 51.73 54.85 0.23 55.08 128.48 116 232.00 0.27 0.53 54.85 58.49 0.24 58.73 128.49 I 117 234.00 0.29 0.56 58.49 62.43 0.26 62.69 128.50 118 236.00 0.30 0.59 62.43 66.12 0.27 66.40 128.51 I 119 120 238.00 240.00 0.31 0.33 0.61 0.64 66.12 69.23 69.23 72.42 0.28 0.30 69.52 72.72 128.52 128.54 121 242.00 0.35 0.67 72.42 76.10 0.31 76.41 128.55 122 244.00 0.36 0.71 76.10 80.06 0.33 80.39 128.56 I 123 246.00 0.38 0.75 80.06 84.21 0.35 84.56 128.57 124 248.00 0.40 0.78 84.21 88.46 0.36 88.83 128.59 125 250.00 0.62 1.02 88.46 102.37 0.42 102.79 128.63 I 126 252.00 0.84 1.45 102.37 131.72 0.54 132.26 128.73 127 254.00 1.05 1.89 131.72 172.91 0.66 173.57 128.84 128 256.00 1.27 2.33 172.91 228.57 0.74 229.31 128.97 I 129 258.00 1.49 2.76 228.57 299.78 0.84 300.62 129.13 130 260.00 1.60 3.09 299.78 378.09 0.95 379.03 129.31 131 262.00 1.47 3.07 378.09 442.96 1.04 444.01 129.52 I 132 264.00 1.22 2.69 442.96 476.24 1.09 477.33 129.63 133 266.00 0.96 2.18 476.24 476.06 1.09 477.16 129.63 134 268.00 0.71 1.67 476.06 447.91 1.05 448.96 129.54 I 135 270.00 0.45 1.16 447.91 396.35 0.97 397.32 129.37 136 272.00 0.20 0.65 396.35 324.95 0.87 325.82 129.19 137 274.00 0.20 0.40 324.95 250.59 0.77 251.36 129.02 I 138 276.00 0.20 0.40 250.59 187.71 0.68 188.39 128.88 139 278.00 0.20 0.40 187.71 137.11 0.56 137.67 128.74 I 140 280.00 0.20 0.40 137.11 102.17 0.42 102.59 128.63 141 282.00 0.20 0.40 102.17 81.02 0.33 81.35 128.56 142 284.00 0.20 0.40 81.02 68.22 0.28 68.50 128.52 I 143 286.00 0.19 0.39 68.22 60.04 0.25 60.28 128.49 144 288.00 0.17 0.36 60.04 53.78 0.22 54.00 128.47 145 290.00 0.15 0.33 53.78 48.24 0.20 48.44 128.46 I 146 292.00 0.14 0.29 48.24 43.15 0.18 43.33 128.44 147 294.00 0.12 0.25 43.15 38.32 0.16 38.48 128.42 148 296.00 0.10 0.22 38.32 33.66 0.14 33.80 128.41 I 149 298.00 0.10 0.20 33.66 29.96 0.12 30.09 128.40 150 300.00 0.10 0.20 29.96 27.73 0.11 27.84 128.39 151 302.00 0.10 0.20 27.73 26.37 0.11 26.48 128.39 I 152 304.00 0.10 0.20 26.37 25.55 0.11 25.66 128.38 I Page 6of 8 User Name: Gary Lipska Project: O'gara-Carlsbad Scenario: BASIN-A Date: 06-16-08 Time: 19:56:14 Intv Time Inflow A B C Outflow Storage Elev (mm) (cfs) (cfs) (cfs) (cfs) (cfs) (Cu ft) (ft) 153 306.00 0.10 0.20 -------------------------------------------------------------------------------- 25.55 25.06 0.10 25.16 128.38 154 308.00 0.10 0.20 25.06 24.76 0.10 24.86 128.38 155 310.00 0.10 0.20 24.76 24.58 0.10 24.68 128.38 156 312.00 0.10 0.20 24.58 24.47 0.10 24.57 128.38 157 314.00 0.10 0.20 24.47 24.40 0.10 24.50 128.38 158 316.00 0.10 0.20 24.40 24.36 0.10 24.46 128.38 159 318.00 0.10 0.20 24.36 24.34 0.10 24.44 128.38 160 320.00 0.10 0.20 24.34 24.32 0.10 24.42 128.38 161 322.00 0.10 0.20 24.32 24.31 0.10 24.41 128.38 162 324.00 0.10 0.20 24.31 24.31 0.10 24.41 128.38 163 326.00 0.10 0.20 24.31 24.30 0.10 24.40 128.38 164 328.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 165 330.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 166 332.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 167 334.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 168 336.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 169 338.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 170 340.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 171 342.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 172 344.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 173 346.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 174 348.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 175 350.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 176 352.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 177 354.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 178 356.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 179 358.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 180 360.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 181 362.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 182 364.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 183 366.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 184 368.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 185 370.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 186 372.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 187 374.00 0.10 0.20 24.30 24.30 0.10 24.40 128.38 188 376.00 0.09 0.19 24.30 23.86 0.10 23.96 128.38 189 378.00 0.07 0.16 23.86 22.29 0.09 22.38 128.37 190 380.00 0.05 0.13 22.29 19.59 0.08 19.68 128.36 191 382.00 0.04 0.09 19.59 16.22 0.07 16.29 128.35 192 384.00 0.02 0.05 16.22 12.43 0.05 12.48 128.34 193 386.00 0.00 0.02 12.43 8.40 0.03 8.43 128.33 194 388.00 0.00 0.00 8.40 5.08 0.02 5.10 128.32 195 390.00 0.00 0.00 5.08 3.08 0.01 3.09 128.31 I Page 7 of 8 I I I I I I I I I I I I I I I I I I I User Name: Gary Lipska Date: 06-16-08 Project: O'gara-Carlsbad Time: 19:56:14 Scenario: BASIN-A Intv Time Inflow A B C Outflow Storage Elev I (mm) (cfs) (cfs) (cfs) (cfs) (cfs) (cu ft) (ft) 196 392.00 0.00 0.00 3.08 1.86 0.01 1.87 128.31 197 394.00 0.00 0.00 1.86 1.13 0.00 1.13 128.30 198 396.00 0.00 0.00 1.13 0.68 0.00 0.68 128.30 199 398.00 0.00 0.00 0.68 0.41 0.00 0.41 128.30 I 200 400.00 0.00 0.00 0.41 0.25 0.00 0:25 128.30 201 402.00 0.00 0.00 0.25 0.15 0.00 0.15 128.30 I 202 203 404.00 406.00 0.00 0.00 0.00 0.00 0.15 0.09 0.09 0.06 0.00 0.00 0.09 0.06 128.30 128.30 204 408.00 0.00 0.00 0.06 0.03 0.00 0.03 128.30 I 205 206 410.00 412.00 0.00 0.00 0.00 0.00 0.03 0.02 0.02 0.01 0.00 0.00 0.02 0.01 128.30 128.30 207 414.00 0.00 0.00 0.01 0.01 0.00 0.01 128.30 208 416.00 0.00 0.00 0.01 0.00 0.00 0.00 128.30 I 209 418.00 0.00 0.00 0.00 0.00 0.00 0.00 128.30 210 420.00 0.00 0.00 0.00 0.00 0.00 0.00 128.30 I I Li I I I I I I I I Page 8 of 8 EX. ASPH k 76j6 0/ / LiJrOfI I I uJ / H I ol QIII 001 ' -o )d _ N\ I I >u II .bJ I I Co ajo_ Ar 716,11 I I I \ T 4 62.50 I I I j V ------ / / C*sTQUAPIN AVEi I I I -----Eq I-- I - j ASPH " EX. CONC / \ \ —_ I -___ Nè11'5\4't 21.8k' I I - \ \\ I I ii 1\J I I I I I HIGHLAAMD—JAMES > 171 TM AA CAP )(J-)(J( XD /II ()>< EX. 12" CON4. I [ - STORM DRAIN PER DWG. 1317-4 U ICY- CTC )i E. 10, Lli Uj — 00 ' iI III I ( PRIVATE J I iII III I SEMENT FOR Il , If- OF LOT 2 k'JJI I I SEE NOTE REFERENCE I I I I LOT 'A' ON JAMES DRIVE PROPOSED 10' AIVATE i-i r I I -.GROS--SiCTION BELOW DRAINAGE EASEA.NT FOR I' THE BENEFIT FkOTS 1,2,4&5 I I &)-8O/; 1 LAT(TORE Al f JJ _ frc 1 I I ji Il, I"\ I," I 11 CIIIIQ Ii IL-1 I 1 I II I I 1 Q k I I 00 I i till I I I I' )=8045 S.F. 00 I B § -A .' coo—_ ACRES LAT. R ::~jj I FO 142.1 . I I IU C I I IEX. FIRE HYDRANT I SEE DETAIL "Q" >ON SHEET 2 =7932 S.F. J Iji , I I I PROPOSED' O' PRIVATE I DRAINAG& EASEMENT FOR I 1>< I I I if CJ,O THE BENEFIT O LOTS 1,2,3&4 ii I LjJ I I NEW 4" )_HJI$J I I , _E'IL 11 1 °H E 4'VCP LAT. I / \(IIOBE IIAA' I I AANDONED) PLIA7'C F . / J ! i FL 122.68 .69 7. \\ /1 I / Ap'-POST CONSTRUCT/ON SCALE: 1"=20' CITY OF OCEANSIDE H II GH WAY SYMBOL LEGEND DESCRIPTION SYMBOL ELEVATION, TOP OF STRUCTURE TOP ELEVATION, TOP OF WALL ________TW ELEVATION, TOP OF CURB ________TC ELEVATION, FINISH FLOOR ________FE ELEVATION, FINISH SURFACE FS ELEVATION, FINISH GRADE FG ELEVATION, TOP OF GRATE TG ELEVATION, HIGH POINT ________HP ELEVATION, LOW POINT ________LP ELEVATION, FLOW LINE ________FL ASS WOOD AVE. --- GRASS OR TURF LINED OPTION OVER LANDLOK TURF REINFORCEMENT j CITY OF VISTA - - fl1Oi4 ICU 1 S 20 40 a- I CIVIL ENGINEERING LAND PLANNING Engineering 1843 : .• Place ' - CA ; 4 Fam (760) 439-2866 DETAIL: GRASS LINED DRAINAGE SWALE NO SCALE NOTES-. PLACE 3 ANCHORS PER SQUARE YARD OF MATERIAL FOR GRASS OR TURF OPTION, INSTALL LANDLOK TRM 450 TURF REINFORCEMENT MATS NOT TO SCALE IUIINI IT IYIt\ - Y ATE PRE A E N E HE PERVISION ElF: --DATE iqlw GARY frPSKA R E 23080 EXP ES 12/31/09 PLOT DATES 6-19-08 I ill .L rI iH I n ii 1 I I I ( K0 It i I : I H - - - - - - - - - - - 6~ 4— ----- — L Cj".501 \\ •\\\ \\ \\ ) \\ç 7 7 \70 ~7 mr 7"7 T \\ ) I \ \\ \\ \ \\ \\ \\ \ I I \\• \ / \ \ \ \\ 4 I \\ \ I H I GHLAND JAMES TM xx-xx/cDP XX-XK x k I (I I 'I rl - I jS ITC (i2.40) / I I ca I \ \ I // I ,I N I 1/ •I N .h1 I I I 1 7 -1-E I ( L650 _ I I \ ) \ 207 3034I 1 \ \ 1 1 ' 1 r / I I I \ / Ar I \ ) i \ I I Tc46Q \ \\' II - I / k \ \\ \ \ \ \\ (iI APX 207--\11130-4,951 iTEJ 1/m Hj /4tt • • \ ' \•Ar . // I • J I // L • i\ IH H 7 / 7 I II 2 i Li >k ) r __ y \ II I I I- • I I I\ I - 1 ( d IT )/\ <'/N I •. /1 DRAIIA-ANAGE MAP- PRE- CONSTRUCT/ON SCALE: 1 "=20' CITY OF OCEANSIDE SYMBOL LEGEND cID-rlr\Nl SYMBOL ELEVATION, TOP OF STRUCTURE —TOP ELEVATION, TOP OF WALL ________TW ELEVATION, TOP OF CURB ________TC ELEVATION, FINISH FLOOR ________FF ELEVATION, FINISH SURFACE ES ELEVATION, FINISH GRADE FG ELEVATION, TOP OF GRATE TG ELEVATION, HIGH POINT _________HP ELEVATION, LOW POINT ________LP ELEVATION, FLOW LINE ________FL 1 S 20 40 S CIVIL ENGINEERING PLANNING A Campesino Place ,: A • 9 A 2802 .9 439-2866 BASSWOOD AVE.'\J'] rri 1- 's \\\\ C \\ \\ \\ -y CITY OF VISTA SITE L. (Li4 \ \ T_~ No. 23080 OCEAN \ \ \ g AIRPORT GARY IPSKA RCE 23080 EXPIRES 12/31/09 VICINI I T IYIP\F NOTTOSCALE AD PLOT DATE: 6-19- I I I I I I ATTACHMENT "B" I I I I I I I I II] I I I Targeted Constituents El Sediment A El Nutnenis El Trash El Metals A El Bacteria El CI and Grease A El Organics A Legend (Rerm Va! Effectiveness) Low Uk-tgh A Medium Vegetated Swale TC-30 Design Considerations . Tributary Area . Area Required Slope Wafer Availability Description Vegetated swales are open, shallow channels with vegetation covering the side slopes and bottom that collect and slowly convey nmoff flow to downstream discharge points. They are designed to treat runoff through filtering by the vegetation in the channel, filtering through a subsoil matrix, and/or infiltration into the underlying soils. Swales can be natural or manmade. They trap particulate pollutants (suspended solids and trace metals), promote infiltration, and reduce the flow velocity of stormwater runoff. Vegetated swales can serve as part of a stormwater drainage system and can replace curbs, gutters and storm sewer systems. California Experience Caltrans constructed and monitored six vegetated swales in southern California. These swales were generally effective in reducing the volume and mass of pollutants in runoff. Even in the areas where the annual rainfall was only about 10 inches/y-, the vegetation did not require additional irrigation. One factor that strongly affected performance was the presence of large numbers of gophers at most of the sites. The gophers created earthen mounds, destroyed vegetation, and generally reduced the effectiveness of the controls for TSS reduction. Advantages If properly designed, vegetated, and operated, swales can serve as an aesthetic, potentially inexpensive urban development or roadway drainage conveyance measure with significant collateral water quality benefits. M R January 2003 California Stormwater BMP Handbod< 1 of 13 New Development and Redevelopment www.cabmphandbooks, corn I TC-30 Vegetated Swale Roadside ditches should be regarded as significant potential swale/buffer strip sites and should be utilized for this purpose whenever possible. Limitations Can be difficult to avoid cbannelization. • May not be appropriate for industrial sites or locations where spills may occur Grassed swales cannot treat a very large drainage area. Large areas may be divided and treated using multiple swales. A thick vegetative cover is needed for these practices to function properly. They are impractical in areas with steep topography. They are not effective and may even erode when flow velocities are high, if the grass cover is not properly maintained. In some places, their use is restricted by law: many local municipalities require curb and gutter systems in residential areas. Swales are mores susceptible to failure if not properly maintained than other treatment BMPs. Design and Sizing Guidelines Flow rate based design determined by local requirements or sized so that 85% of the annual runoff volume is discharged at less than the design rainfall intensity. Swale should be designed so that the water level does not exceed 2/3rd5 the height of the grass or 4 inches, which ever is less, at the design treatment rate. Longitudinal slopes should not exceed 2.5% Trapezoidal channels are normally recommended but other configurations, such as parabolic, can also provide substantial water quality improvement and may be easier to mow than designs with sharp breaks in slope. Swales constructed in cut are preferred, or in fill areas that are far enough from an adjacent slope to minimize the potential for gopher damage. Do not use side slopes constructed of A which are prone to siruciural damage by gophers and other burrowing animals. A diverse selection of low growing, plants that thrive under the specific site, climatic, and watering conditions should be specified. Vegetation whose growing season corresponds to the wet season are preferred. Drought tolerant vegetation should be considered especially for swales that are not part of a regularly irrigated landscaped area. The width of the swale should be determined using Manning's Equation using a value of 0.25 for Manning's n. 2 of 13 California Stormwater BMP Handbook January 2003 New Development and Redevelopment www.cabmphandbooks.com F Vegetated Swale TC-30 Cons tructiin&/Iitspevtion Considerations I . Include directions in the specifications for use of appropriate fertilizer and soil amendments based on soil properties determined through testing and compared to the needs of the vegetation requirements. I . Install swales at the time of the year when there is a reasonable chance of successful establishment without irrigation; however, it is recognized that rainfall in a given year may not be sufficient and temporary irrigation may be used. I . If sod Liles musi be used, they should be placed so Lint there are no gaps between the Liles; stagger the ends of the tiles to prevent the formation of channels along the swale or strip. I . Use a roller on the sod to ensure that no air pockets form between the sod and the soil. . Where seeds are used, erosion controls will be necessary to protect seeds for at least 75 days I after the first rainfall of the season. Performance I The literature suggests that vegetated swales represent a practical and potentially effective technique for controlling urban runoff quality. While limited quantitative performance data exists for vegetated swales, it is known that check dams, slight slopes, permeable soils, dense grass cover, increased contact time, and small storm events all contribute to successful pollutant I removal by the swale system. Factors decreasing the effectiveness of swales include compacted soils, short runoff contact time, large storm events, frozen ground, short grass heights, steep I slopes, and high runoff velocities and discharge rates. Conventional vegetated swale designs have achieved mixed results in removing particulate pollutants. A study performed by the Nationwide Urban Runoff Program (NURP) monitored ' three grass swales in the Washington, D.C., area and found no significant improvement in urban runoff quality for the pollutants analyzed. However, the weak performance of these swales was attributed to the high flow velocities in the swales, soil compaction, steep slopes, and short grass height. I Another project in Durham, NC, monitored the performance of a carefully designed artificial swale that received runoff from a commercial parking lot. The project tracked ii storms and ' concluded that particulate concentrations of heavy metals (Cu, Pb, Zn, and Cd) were reduced by approximately 50 percent However, the swale proved largely ineffective for removing soluble nutrients. I The effectiveness of vegetated swales can be enhanced by adding check dams at approximately 17 meter (50 foot) increments along their length (See Figure 1). These dams maximize the retention time within the swale, decrease flow velocities, and promote particulate settling. I Finally, the incorporation of vegetated filter strips parallel to the top of the channel banks can help to treat sheet flows entering the swale. I Only 9 studies have been conducted on all grassed channels designed for water quality (Table 1). The data suggest relatively high removal rates for some pollutants, but negative removals for some bacteria, and fair performance for phosphorus. I January 2003 California Stormwater BMP Handbook 3 of 13 I New Development and Redevelopment www.cabrnphandbooks.com TC-30 Vegetated Swale Table 1 Grassed swale pollutant removal efficiency data Removal Efficiencies (% Removal) Study TSS TP TN NO3 Metals Bacteria Type altrans 2002 77 8 67 66 83-90 -33 dry swales 3oldberg 1993 67.8 4.5 - 3L4 42-62 -100 grassed channel Seattle Metro and Washington )epartmentof Ecology t992 60 - 45 - - - -25 2-16 - grassed channel Seattle Metro and Washington )epartment of Ecology, 1992 83 - 29 - - - -25 46-73 -25 grassed channel Wang et al., 1981 8o - - - 70-80 - dry swale Dorman et al., 1989 98 iS - 45 37-81 - dry swale Harper, 1988 87 83 84 80 88-90 - dry swale ercher et al, 1983 99 99 99 99 99 - dry swale Harper, 1988. 81 17 40 52 37-69 - vet swale UWI, 1995 67 39 - 9 -35 Lu 6 - wet swale While it is difficult to distinguish between different designs based on the small amount of available data, grassed channels generally have poorer removal rates than wet and dry swales, although some swales appear to export soluble phosphorus (Harper, 1988; Koon, 1995). It is not clear why swales export bacteria. One explanation is that bacteria thrive in the warm swale soils. Siting Criteria The suitability of a swale at a site will depend on land use, size of the area serviced, soil type, slope, imperviousness of the contributing watershed, and dimensions and slope of the swale system (Schueler et at, 1992). In general, swales can be used to serve areas of less than 10 acres, with slopes no greater than 5 %. Use of natural topographic lows is encouraged and natural drainage courses should be regarded as significant local resources to be kept in use (Young et at, 1996). Selection Criteria (NCTCOG, 1993) a Comparable performance to wet basins a Limited to treating a few acres a Availability of water during dry periods to maintain vegetation . Sufficient available land area Research in the Austin area indicates that vegetated controls are effective at removing pollutants even when dormant. Therefore, irrigation is not required to maintain growth during dry periods, but may be necessary only to prevent the vegetation from dying. 4 of 13 California Stormwater BMP Handbook January 2003 New Development and Redevelopment www.cabmphancbooks.com I I I I 1 I I I I I I Vegetated Swale TC-30 The topography of the site should permit the design of a channel with appropriate slope and cross-sectional area. Site topography may also dictate a need for additional structural controls. I Recommendations for longitudinal slopes range between and 6 percent Flatter slopes can be used, if sufficient to provide adequate conveyance. Steep slopes increase flow velocity, decrease detention time, and may require energy dissipating and grade check. Steep slopes also can be I managed using a series of check dams to terrace the swale and reduce the slope to within acceptable limits. The use of check dams with swales also promotes infiltration. I Additional Design Guidelines Most of the design guidelines adopted for swale design specify a minimum hydraulic residence time of 9 minutes. This criterion is based on the results of a single study conducted in Seattle, I Washington (Seattle Metro and Washington Department of Ecology, 1992), and is not well supported. Analysis of the data collected in that study indicates that pollutant removal at a residence time of 5 minutes was not significantly different, although there is more variability in that data. Therefore, additional research in the design criteria for swales is needed. Substantial I pollutant removal has also been observed for vegetated controls designed solely for conveyance (Barrett et al, 1998); consequently, some flexibility in the design is warranted. I Many design guidelines recommend that grass be frequently mowed to maintain dense coverage near the ground surface. Recent research (Colwell et al., 2000) has shown mowing frequency or grass height has little or no effect on pollutant removal. I Sunzmcwy of Design Recommendations The swale should have a length that provides a minimum hydraulic residence time of at least 10 minutes. The maximum bottom width should not exceed 10 feet unless a I dividing berm is provided. The depth of flow should not exceed 2/3rd5 the height of the grass at the peak of the water quality design storm intensity. The channel slope I should not exceed 2.5%. A design grass height of 6 inches is recommended. Regardless of the recommended detention time, the swale should be not less than I 100 feet in length. The width of the swale should be determined using Manning's Equation, at the peak 1 of the design storm, using a Manning's n of 0.25. The swale can be sized as both a treatment facility for the design storm and as a ' conveyance system to pass the peak hydraulic flows of the loo-year storm if it is located "on-line." The side slopes should beno steeper than 3:1 (H:V). Roadside ditches should be regarded as significant potential swale/buffer strip sites I and should be utilized for this purpose whenever possible. If flow is to be introduced through curb cuts, place pavement slightly above the elevation of the vegetated areas. Curb cuts should be at least 12 inches wide to prevent clogging. I 7) Swales must be vegetated in order to provide adequate treatment of runoff. It is important to maximize water contact with vegetation and the soil surface. For general purposes, select fine, close-growing, water-resistant grasses. If possible, I divert runoff (other than necessary irrigation) during the period of vegetation January 2003 California Storrnwater BIV1P Handbook 5 of 13 I New Development and Redevelopment www.cabmphandbooks.com TC-30 Vegetated Swale establishment. Where runoff diversion is not possible, cover graded and seeded areas with suitable erosion control materials. Maintenance The useful life of a vegetated swale system is directly proportional to its maintenance. frequency. If properly designed and regularly maintained., vegetated swales can last indefinitely. The maintenance objectives for vegetated swale systems include keeping up the hydraulic and removal efficiency of the channel and maintaining a dense, healthy grass cover. Maintenance activities should include periodic mowing (with grass never cut shorter than the design flow depth), weed control, watering during drought conditions, reseeding of bare areas, and clearing of debris and blockages. Cuttings should be removed from the channel and disposed in a local composting facility. Accumulated sediment should also be removed manually to avoid concentrated flows in the swale. The application of fertilizers and pesticides should be minimal. Another aspect of a good maintenance plan is repairing damaged areas within a channel. For example, if the channel develops ruts or holes, it should be repaired utilizing a suitable soil that is properly tamped and seeded. The grass cover should be thick; if it is not; reseed as necessary. Any standing water removed during the maintenance operation must be disposed to a sanitary sewer at an approved discharge location. Residuals (e.g., silt, grass cuttings) must be disposed in accordance with local or State requirements. Maintenance of grassed swales mostly involves maintenance of the grass or wetland plant cover. Typical maintenance activities are summarized below: R Inspect swales at least twice annually for erosion, damage to vegetation, and sediment and debris accumulation preferably at the end of the wet season to schedule summer maintenance and before major fall runoff to be sure the swale is ready for winter. However, I additional inspection after periods of heavy runoff is desirable. The swale should be checked for debris and lilier, and areas of sediment aceumulaLion. I Grass height and mowing frequency may not have a large impact on pollutant removal. Consequently, mowing may only be necessary once or twice a year for safety or aesthetics or to suppress weeds and woody vegetation. I w Trash tends to accumulate in swale areas, particularly along highways. The need for litter removal is determined through periodic inspection, but litter should always be removed prior to mowing. I m Sediment accumulating near culverts and in channels should be removed when it builds up to 75 mm (3 in.) at any spot, or covers vegetation. Im Regularly inspect swales for pools of standing water. Swales can become a nuisance due to mosquito breeding in standing water if obstructions develop (e.g. debris accumulation, invasive vegetation) and/or if proper drainage slopes are not implemented and maintained. I I 6 o 13 California Stormwater BMP Handbook January 2003 New Development and Redevelopment www. cabmphandbooks .com Vegetated Swale TC-30 Cost Construction Cost Little data is available to estimate the difference in cost between various swale designs. One study (SWRPC, 1991) estimated the construction cost of grassed channels at approximately $0.25 per ft-2. This price does not include design costs or contingencies. Brown and Schueler (1997) estimate these costs at approximately 32 percent of construction costs for most stormwater management practices. For swales, however, these costs would probably be significantly higher since the construction costs are so low compared with other practices. A more realistic estimate would be a total cost of approximately $o.50 per ft2, which compares favorably with other stormwater management practices. January 2003 California Stormwater BMP Handbook 7 of 13 New Development and Redevelopment www.cabmphandbooks.com - - - - - - - - - - - - - - - - - - - TC-30 Vegetated Swale Table 2 Swale Cost Estimate (SEWRPC, 1991) unit Cost Total Cost Low Moderate High tw ModeTate lgh Component unit Extent Moblllzation/ Swale I $107 $274 $441 $107 .274 $441 DemablllzBtlon -Uçlit Site Preparetkxl Clearing Acre 0.5 $2,200 $3,600 $5.400 $1,100 $1,90C $2,700 Grabbing' 025 $3,800 $5,200 $13.600 $950 $130C $1,850 Go nore I Yd' 372 $2.10 $3.70 $5,30 $761 $t378 $1.972 Lowoi and TM'....... Yt 1,210 $0.20 $0.36 $0.50 $242 £424 Sites Development Salvaged Topsoil Seed, and Mulch'.. 'y'd 1,210 $0.40 $1.00 $1.60 $464 $1,210 $1,936 Sods Yd 1,210 $1.20 $2.40 $3.60 $1452 $2,904 $4,358 Subtotal -- - -- - -- $5116 $0366 $13660 Contingencies Swale 1 25% 25% 25% $1,279 $2,347 $3.415 Total -- - -- - -- - $6,395 $11,735 $17075 Source: (SEWRPG 1991) Note: Mobi or,IdernobIIIation refers to the orgarizatlan and planning Involved In establishing a vegetabva swab. 'Swale has a bottom width of 1.0 foot, a top wdth of 10 feet with 1:3 side slopes, and a 1,000-foot length. Area cleared = (top width + 10 feet)x swale length. Area grubbed = (top width x swale length). 'Volume excavated = (0 67 x top width x swale depth) x swale length (parabolic cross-section). Area tilled = (top width B(swale depth2) x swale length (parabolic cross-section). 3(tor, widthu seeded = area cleared x 0.5. 'Area sodded = area cleared xis. 8 of 13 CalIfornia Stormwater BMP Hardbook 3a)uary 2003 New Developmen: and Redevelopment www.cabmp-iandbcoks.com - - - - - - - - - - - - - - - - - - - Vegetated Swale TC30 Table 3 Estimated Maintenance Costs (SEWRPC. 19911 Swale Size (DeptEi, and Top Width Component Unit Cost Comment 1.5 Foot Depth, One- 3-Foot Depth 3-Foot Foot Bottom Widttt Bottom WIdth1 21-Foot 10-Fot Top Width Top Width Lawn Mowing $0.85! 1,000 ft1 mowng $0.14 lin ear toot 021 / hneer feat Lawn maintenance area-(top ldfr+ 1101eet)x length. Mow eight 11m08 per year Geriorel Lawn Care $9.00 11,000 ft! year $0.10 1 lirieartoot $0.28 / linear foot Lawn maintenance area (top Wdtn+ loteeflxlength $wal Debris and Utter $O.10/ linear fad /year $0.10!Iirieer1oot $0.10 /linear foot - Rommel (3raea Reseeding with $0.30 / yd' $0.011 Ilneerfoot $0.011 lInear foot Area reveqetated equal 1% Mulch and Fertilliar otlown maintenance area per year Program Adri,lntetratlon and $0.161 linear foot! year, $0.15 / Ilnearfoot .0.15 / lInear foot Irrepect four times per year Swale lnspeclon plus $251 Inspection __ Total $056I lInear foot $.0,'7_t__5 ilinearfoot :enuary 2003 CalIfornia Storrnwater BMP Handbook 9 of 13 New Deveopment and Redevelopment www. cabmphandbookscoTl I TC-30 Vegetated Swale Maintenance Cost I Calirans (2002) estimated the expected annual maintenance cost for a swale with a tributary area of approximately 2 ha al approximately $2,700. Since almost all maintenance wnsisLs of mowing, the cost is fundamentally a function of the mowing frequency. Unit costs developed by I SEWRPC are shown in Table 3. In many cases vegetated channels would be used to convey runoff and would require periodic mowing as well., so there may be little additional cost for the water quality component Since essentially all the activities are related to vegetation I management, no special training is required for maintenance personnel. References and Sources of Additional Information Barrett, Michael E., Walsh, Patrick M., Malina, Joseph F.) Jr., Charbeneau, Randall J, 1998, I "Performance of vegetative controls for treating highway runoff," AS(E Journal of Environmental Engineering, Vol. 124, No. 11, pp. 1121-1128. I Brown, W., and T. Schueler. 1997. The Economics ofStorm water BMPs in the Mid-Atlantic Region. Prepared for the Chesapeake Research Consortium, Edgewater, MD, by the Center for Watershed Protection, Ellicott City, MD. I Center for Watershed Protection (CWP). 1996. Design of Stormwater Filtering Systems. Prepared for the Chesapeake Research Consortium, Solomons, MD, and USEPA Region V, Chicago, IL, by the Center for Watershed Protection, Ellicott City, MD. I Colwell, Shanti R., Homer, Richard R., and Booth, Derek B., 2000. Characterization of Performance Predictors and Evaluation ofMouxing Practices in Biofihtration Swales. Report I to King County Land And Water Resources Division and others by Center for Urban Water Resources Management, Department of Civil and Environmental Engineering, University of Washington, Seattle, WA I Dorman, M.E., J. Hartigan, R.F. Steg, and T. Quasebarth. 1989. Retention, Detention and OuerlundFlow for Pollui wit Removal From Highway Siormwater Runoff. Vol. 1. FHWA/RD 89/202. Federal Highway Administration, Washington, DC. I Goldberg. 1993. Dayton Avenue Swale Biofiltration Study. Seattle Engineering Department, Seattle, WA I Harper, H. 1988. Effects of Stormwater Management Systems on Groundwater Quality. Prepared for Florida Department of Environmental Regulation, Tallahassee, FL, by Environmental Research and Design, Inc., Orlando, FL. I Kercher, W.C., J.C. Landon, and R. Massarelli. 1983. Grassy swales prove cost-effective for water pollution control. Public Works, 16: 53-55. I Koon, J. 1995. Evaluation of Water Quality Ponds and Swales in the Issaquah/East Lake Sammamish Basins. King County Surface Water Management, Seattle, WA, and Washington Department of Ecology, Olympia, WA I Metzger, M. E., D. F. Messer, C. L. Beitia, C. M. Myers, and V. L. Kramer. 2002. The Dark Side Of Stormwater Runoff Management Disease Vectors Associated With Structural BMPs. Stormwater 3(2): 24-39.Oakland, P .H. 1983. An evaluation of stormwater pollutant removal I 10 of 13 California Stormwater BMP Handbook January 2003 New Development and Redevelopment www.cabmphandbooks.com I Vegetated Swale TC-30 I through grassed swale treatment. In Proceedings of the International Symposium of Urban I Hydrology, Hydraulics and Sediment Contro4 Lexington, KY pp. 173-182. Occoquan Watershed Monitoring Laboratory. 1983, Final Report: Metropolitan Washington Urban Runoff Project. Prepared for the Metropolitan Washington Council of Governments, Washington, DC, by the Occoquan Watershed Monitoring Laboratory, Manassas, VA. Pitt, R., and J. McLean. 1986. Toronto Area WatershedManagement Strategy Study: Humber River Pilot Watershed Project. Ontario Ministry of Environment, Toronto, ON. Schueler, T. 1997. Comparative Pollutant Removal Capability of Urban BMPs: A reanalysis. I Watershed Protection Techniques 2(2):379-383. Performance: Seattle Metro and Washington Department of Ecology. 1992. Biofiltration Swale Recommendations and Design Considerations. Publication No. 657. Water Pollution Control I Department, Seattle, WA Southeastern Wisconsin Regional Planning Commission (SWRPC). 1991. Costs of Urban Nonpoint Source Water Pollution Control Measures. Technical report no. 31. Southeastern Wisconsin Regional Planning Commission, Waukesha, WI. U.S. EPA, 1999, Stormwater Fact Sheet Vegetated Swales, Report # 832-F-99-006 I http: //www.epa.gov/owm/mtb/vegswalepdf, Office of Water, Washington DC. Wang, T., D. Spyridakis, B. Mar, and R. Homer. 1981. Transport, Deposition and Control of Heavy Metals in Highway Runoff. FHWA-WA-RD-39-10. University of Washington, Department of Civil Engineering, Seattle, WA. Washington State Department of Transportation, 1995, Highway RunoffManual, Washington I State Department of Transportation, Olympia, Washington. Welborn, C., and J. Veenhuis. 1987. Effects ofRunoff Controls on the Quantity and Quality of I Urban Runoff in Two Locations in Austin, 2X. USGS Water Resources Investigations Report No. 87-4004. U.S. Geological Survey, Reston, VA. Yousef, Y., M. Wanielista, H. Harper, D. Pearce, and R. Tolbert. 1985. Best Management I Practices: Removal of Highway Contaminants By Roadside Swales. University of Central Florida and Florida Department of Transportation, Orlando, FL. Yu, S., S. Barnes, and V. Gerde. 1993. Testing of Best Munugement Produces for Controlling I Highway Runoff. FHWA/VA-93-R16. Virginia Transportation Research Council, Charlottesville, VA I Information Resources Maryland Department of the Environment (MDE). 2000. Maryland Stormwater Design Manual. www.mde.state.mcLus/environment/wma/stormwatermanual. Accessed May 22, I 2001. Reeves, B. 1994. Performance and Condition of Biofikers in the Pacific Northwest Watershed Protection Techniques 1(3):117-119- January 2003 California Stormwater BMP Handbook 11 of 13 New Development and Redevelopment I www.cabmphandbooks.com I TC-30 Vegetated Swale Seattle Metro and Washington Department of Ecology. 1992. Biofiltration Swale Performance. I Recommendations and Design Considerations. Publication No. 657. Seattle Metro and Washington Department of Ecology, Olympia, WA I USEPA 1993. Guidance Specifying Management Measures for Sources ofNonpoint Pollution in Coastal Waters. EPA-840-B-92-002. U.S. Environmental Protection Agency, Office of Water. Washington, DC. I Watershed Management Institute (WMI). 1997. Operation, Maintenance, and Management of Stormwater Management Systems. Prepared for U.S. Environmental Protection Agency, Office of Water. Washington, DC, by the Watershed Management Institute, Ingleside, MD. I I I I I I LI I U I I I 12 of 13 - California Stormwater BMP Handbook January 2003 I New Development and Redevelopment www.cabmphandbooks.com I I I Vegetated Swale TC-30 .............................................--.-...---- pros scclion 015wok silk cIivck dam. 7- Notation: L = Lcncjth or ssaIc irnpoLuidnieni area pr check dais fT} 9sf lrnfl5illflot I it" 1itjtc iii11iiiiiflift0ti1t aria. = Depth of cheek dam ifti Ss = Donors olpe of soak ift!ft = Top width of cheek darn fit- V1,18 enore wkith of check darn n: Zuz = Ratio of horizontal to vettical change in seiak side slope felt:. I I H I I I I H I I I I I H H H I H Juary 2003 California Stormwater BMP Handbook 13 of 13 New Development and Redevelopment www.cabmphandbooks.com H I I I I Li I I I I ATTACHMENT "C" I I I I I I I I I I I ikA_JLô rL.I,ui u I..,1... ...- I .-'.. NPOES PERMIT " LITE' 1 1.]II NMI, Ihanks to the Santa Monica Restoration Bay Project, the I National Pollutant Discharge Elimination Systems document was translated into easy to understand language. ABOUT URBAN AND STORM WATER RUNOFF... Urban and storm water runoff is a serious concern, in both dry and rainy season. It is contaminated with pesticides, fertilizers, animal droppings, trash, food wastes, automotive byproducts and other toxic substances that are part of our urban environment. Waters that flow over streets, parking lots, construction sites and industrial facilities carry these pollutants through a 5,000-mile storm drain network directly to the lakes, streams and beaches of Southern California. I Urban runoff is the largest source of unregulated pollution to the waterways and coastal areas of the United States. Locally, we see the impacts in increased health risks to swimmers near storm drains, high I concentrations of toxic metals in harbor and ocean sediments, and toxicity to aquatic life. I These impacts translate into losses to the County's $2 billion a year tourism economy, loss of recreational resource, dramatic cost increases for cleaning up contaminated sediments and impaired function and vitality of our natural resources. I HISTORY The Clean Water Act of 1987 established requirements for storm water I discharges under the National Pollutant Discharge Elimination System NPDES) program. In response to those requirements, the State of California issued a five-year permit for municipal storm water discharges I to Los Angeles County in June 1990. The 1990 permit was very general in nature, resulting in storm water programs that varied widely from city to city. The 1996 permit, a reissuance of the 1990 permit, therefore seeks to provide better direction I by specifying actions needed to comply with permit requirements. This permit is the result of one and a half years of discussions between I representatives of the Los Angeles Regional Water Quality Control Board (Regional Board), Los Angeles County, the City of Los Angeles, three smaller cities, and the environmental community. It also I incorporates extensive comments received from all interested parties on two earlier drafts. I GOALS OF THE MUNICIPAL STORM WATER PERMIT To attain and protect the beneficial uses of water bodies in Los Angeles County; I • To reduce pollutants in storniwater to the maximum extent practicable; and I http://www.lastormwater.org/pages/npdeslit.hlm I ',ILJu U LL¼.-LLU.UI .L.c..,i To evaluate compliance with the objectives and requirements contained in the permit. I REQUIREMENTS OF THE STORM WATER MANAGEMENT PROGRAM In general, the permit requires implementation of both the Storm Water Management Program contained in the permit, the elements of the Countywide Stormwater Management Plan (CSWMP) or Watershed Management Area Plans (WMAP) that will be developed pursuant to the permit The Countywide Storm Water Management Plan I and Water Management Area Plans Much of the permit details the Storm Water Management Program elements and "what" should be induded in the CSWMP. Developing the I specified program elements will require that Permittees determine "how" actions will be implemented. Program elements, once developed, will then be compiled into the unified implementation plan known as the I CSWMP. The Watershed Management Area Plans are to be devdoped later in the permit cycle. They are based on the requirements of the permit and the I CSWMP, but will also indude actions that address water quality problems and concerns that are unique to the six watershed areas of Los Angeles County. Once developed and approved, the WMAP superceded the l CSWMP. The storm water management program is comprised of seven elements, I the objectives of which are to: 1. Effectively manage and coordinate implementation of the storm water program; I 2. Identify and eliminate illicit connections and illicit discharges to the storm drain system; Reduce storm water impacts associated with development and I redevelopment projects; Reduce storm water quality impacts associated with public agency activities; I 5. Increase public knowledge about the impacts of storm water pollution and about actions that can be taken to prevent pollution. 6. Increase knowledge and understanding about the quality, quantity, sources, and impacts of urban runoff; and I 7. Evaluate the effectiveness of implementing storm water management programs. I 5/13/( I LI I Iii I I I I ATTACHMENT "D" Li I I LI Li I I I I I I I I GENERAL CATAGORIES FOR WATER POLLUTION Urban runoff from a developed site has the potential to contribute pollutants, including oil and I grease, suspended solids, metals, gasoline, pesticides, and pathogens to the storm water conveyance system and receiving waters. For the purposes of identifying pollutants of concern I and associated storm water BMPs, pollutants are grouped in nine general categories as follows: Sediments -Sediments are soils or other surficial materials eroded and then I transported or deposited by the action of wind, water, ice, or gravity. Sediments can increase turbidity, clog fish gills, reduce spawning habitat, lower young aquatic organisms survival rates, smother bottom dwelling organisms, and suppress aquatic vegetation growth. Nutrients- Nutrients are inorganic substances, such as nitrogen and phosphorus. They I commonly exist in the form of mineral salts that are either dissolved or suspended in water. Primary sources of nutrients in urban runoff are fertilizers and eroded soils. Excessive discharge of nutrients to water bodies and streams can cause excessive aquatic algae and plant growth. Such I excessive production, referred to as cultural eutrophication, may lead to excessive decay of organic matter in the water body, loss of oxygen in the water, release of toxins in sediment, and I the eventual death of aquatic organisms. Metals -Metals are raw material components in non-metal products such as fuels, adhesives, I paints, and other coatings. Primary source of metal pollution in storm water are typically commercially available metals and metal products. I Metals of concern include cadmium, chromium, copper, lead, mercury, and zinc. Lead and chromium have been used as corrosion inhibitors in primer coatings and cooling tower systems. At low concentrations naturally occurring in soil, metals are not toxic. However, at higher I concentrations, certain metals can be toxic to aquaticlife. Humans can be impacted from contaminated groundwater resources, and bio accumulation of metals in fish and shellfish. I Environmental concerns, regarding the potential for release of metals to the environment, have already led to restricted metal usage in certain applications. I 4. Organic Compounds -Organic compounds are carbon-based. Commercially available or naturally occurring organic compounds are found in pesticides, solvents, and hydrocarbons. I Organic compounds can, at certain concentrations, indirectly or directly constitute a hazard to life or health. When rinsing off objects, toxic levels of solvents and cleaning compounds can be discharged to storm drains. Dirt, grease, and grime retained in the cleaning fluid or rinse water I may also adsorb levels of organic compounds that are harmful or hazardous to aquatic life. I 5. Trash & Debris -Trash (such as paper, plastic, polystyrene packing foam, and aluminum materials) and biodegradable organic matter (such as leaves, grass cuttings, and food waste) are general waste products on the landscape. The presence of trash & debris may have a significant Li] I impact on the recreational value of a water body and aquatic habitat Excess organic matter can create a high biochemical oxygen demand in a stream and thereby lower its water quality. Also, in areas where stagnant water exists, the presence of excess organic matter can promote septic I conditions resulting in the growth of undesirable organisms and the release of odorous and hazardous compounds such as hydrogen sulfide. ' Oxygen-Demanding Substances - This category includes biodegradable organic material as well as chemicals that react with dissolved oxygen in water to form other compounds. Proteins, carbohydrates, and fhts are examples of biodegradable organic compounds. Compounds such as I ammonia and hydrogen sulfide are examples of oxygen-demanding compounds. The oxygen demand of a substance can lead to depletion of dissolved oxygen in a water body and possibly the development of septic conditions. Oil and Grease - Oil and grease are characterized as high-molecular weight organic I compounds. Primary sources of oil and grease are petroleum hydrocarbon products, motor products from leaking vehicles, esters, oils, fats, waxes, and highmolecular-weight fattyacids. Introduction of these pollutants to the water bodies are very possible due to the wide uses and applications of some of these products in municipal,, residential, commercial, industrial, and construction areas. Elevated oil and grease content can decrease the aesthetic value of the water body, as well as the water quality. Bacteria and Viruses - Bacteria and viruses are ubiquitous microorganisms that thrive under I certain environmental conditions. Their proliferation is typically caused by the transport of animal or human fecal wastes from the watershed. Water, containing excessive bacteria and viruses can alter the aquatic habitat and create a harmful environment for humans and aquatic life. Also, the I decomposition of excess organic waste causes increased growth of undesirable organisms in the water. Pesticides - Pesticides (including herbicides) are chemical compounds commonly used to control nuisance growth or prevalence of organisms. Excessive application of a pesticide may result in runoff containing toxic levels of its active component. I I Li I I I I I ATTACHMENT "E" I I I I I I I I I Li I i\OiLpUUiL )UWL I U iLiiiI. ILii. 11U11 .I1ii I Pointer No. 1 EPA84 1 -F-96-004A I Nonpoint Source Pollution: The Nation's Largest Water Quality Problem I Why is there still water that's too dirty for swimming, fishing or jd. " drinking? Why are native species of plants and animals disappearing - ' from many rivers, lakes, and coastal waters? I Z. The United States has made tremendous advances in the past 25 years - to clean up the aquatic environment by controlling pollution from I I-!fl 7W industries and sewage treatment plants. Unfortunately, we did not do II rflhl enough to control pollution from diffuse, or nonpoint, sources. Today, nonpoint source (NPS) pollution remains the Nation's largest source of water quality problems. It's the main reason that approximately 40 rveyed rivers, lakes, and estuaries are not clean percent of our su I Three Leading Sources of I enough to meet basic uses such as fishing or swimming. Water Quality mpairment Rank Rivrc LakeG Eduvies NPS pollution occurs when rainfall, snowmelt, or irrigation runs over I - land or through the ground, picks up pollutants, and deposits them into Aoriobira PinwItJra Urban -no' rivers, lakes, and coastal waters or introduces them into ground water. - M.irUCq3a1 MJfliOI)8l Municipal Imagine the path taken by a drop of rain from the time it hits the I 2 point point point ground to when it reaches a river, ground water, or the ocean. Any Bouroea MUTD99 bource — pollutant it picks upon its journey can become part of the NPS Stream/ 3 babIt Urb, runoff Agriculture problem. NPS pollution also includes adverse changes to the - I I clienges vegetation, shape, and flow of streams and other aquatic systems. oUro,: tar NtwraI Q.mlLylrwiwrZ 1P9L NPS pollution is widespread because it can occur any time activities disturb the land or water. Agriculture, forestry, grazing, septic systems, recreational boating, urban runofl construction, physical changes to NPS pollution occurs when stream channels, and habitat degradation are potential sources of NPS I water runs over land or through pollution. Careless or uninformed household management also the ground, picks up pollutants, contributes to NPS pollution problems. and deposits them in surface I waters or introduces them into groundwater The latest National Water Quality Inventory indicates that agriculture A is the leading contributor to water quality impairments, degrading 60 percent of the impaired river miles and half of the impaired lake acreage I surveyed by states, territories, and tribes. Runoff from urban areas is the largest source of water quality impairments to surveyed estuaries (areas near the coast where seawater mixes with freshwater). I The most common NPS pollutants are sediment and nutrients. These wash into water bodies from agricultural land, small and medium-sized animal feeding operations, construction sites, and other areas of disturbance. Other common NPS pollutants include pesticides, pathogens (bacteria and viruses), I salts, oil, grease, toxic chemicals, and heavy metals. Beach closures, destroyed habitat, unsafe drinking water, fish kills, and many other severe environmental and human health problems result from NPS i pollutants. The pollutants also ruin the beauty of healthy, clean water habitats. Each year the United States spends millions of dollars to restore and protect the areas damaged by NPS pollutants. I http://www.epa.gov/OWOWiNPS/facts/pointl.htm 9/27/01 '.'UiLjJJm )(JUL.- I UUtLW. A 11' A c.L1LJ11 A L.A LL A £ ULLAL 01 i I I Progress I During the last 10 years, our country has made significant headway in addressing NPS pollution, At the federal level, recent NPS control programs include the Nonpoint Source Management Program established by the 1987 Clean Water Act Amendments, and the Coastal Nonpoint Pollution Program I established by the 1990 Coastal Zone Act Reauthorization Amendments. Other recent federal programs, as well as state, territorial, tribal and local programs also tackle NPS problems. I In addition, public and private groups have developed and used pollution prevention and pollution reduction initiatives and NPS pollution controls, known as management measures, to clean up our water efficiently. Water quality monitoring and environmental education activities supported by I government agencies, tribes, industry, volunteer groups, and schools have provided information about NPS pollution and have helped to determine the effectiveness of management techniques. Also, use of the watershed approach has helped communities address water quality problems caused by NPS pollution. The watershed approach looks at not only a water body but also the entire area that drains into it. This allows communities to focus resources on a watersheds most serious environmental problems--which, in many instances, are caused by NPS pollution. Just as important, more citizens are practicing water conservation and participating in stream walks, beach cleanups, and other environmental activities sponsored by community-based organizations. By helping out in such efforts, citizens address the Nation's largest water quality problem, and ensure that even more of our rivers, lakes, and coastal waters become safe for swimming, fishing, drinking, and aquatic life. RELATED PUBLICATIONS Additional fact sheets in the Nonpoint Pointers series (EPA-841-F-96-004) Watershed Approach Framework (EPA840-S-96-00 1) EPA Journal, Vol. 17, No. 5, Nov/Dec 1991, (EPA-22K-1005) Managing Nonpoint Source Pollution: Final Report to Congress on Section 319 of the Clean Water Act (EPA-506/9-90) NPS News-Notes (EPA-84 1-N-92-003) Polluted (EPA-841-F-94-005) The Quality of Our Nation's Water: 1994 (EPA-841-S-95-004) The Watershed Protection Approach (EPA-503/9-92/002) To order any of the above EPA documents call or fax the National Service Center for Environmental Publications. Tel (513) 489-8190 http://www.epa.gov/OWOW/NPS/facts/pointl.htm 9/27/01 ,•- I Fax (513) 489-8695 I FOR MORE INFORMATION I U.S. Environmental Protection Agency Nonpoint Source Control Branch I Washington DC 20460 1 Office of Wetlands, Oceans & Watersheds Home I Watershed Protection Home I EPA HomeI Office of Water I Search I Comments Contacts Revised: 04/10/2001 01:12:01 I I I I I I I I I I I I http://www.epa.gov/OWOWNPS/facts/Pointl.htm 9/27/01 UpjiiJ. L'ii j L... lOt I UUti_ ill VOl tL-iIICZAL liZ 1'U1.1.ILJu it. t... i .Llt..L •.t - 1. t.. L t.;t .. Pointer No. 2 EPA84 1 -F-96-004B Opportunities for Public Involvement in Nonpoint Source Control > / Over the last 25 years, communities have played an important role in addressing nonpoint source (NPS) pollution, the Nation's leading source .1 (of water quality problems. When coordinated with federal, state, and local environmental programs and initiatives, community-based NPS 'control efforts can be highly successful. To learn about and help control . NPS pollution, contact the community-based organizations and environmental agencies in your area. These groups often have information about how citizens can get involved in the following types $: of NPS control activities. Volunteer Monitoring kurce (NPS) pollution Local groups organize volunteers of all skill levels to gather water quality data. This information can help government agencies understand the magnitude of NPS pollution. More than 500 active volunteer monitoring groups currently operate throughout the United States. Did you know Monitoring groups may also have information about other NPS that volunteers pollution projects, such as beach cleanups, stream walks, and often collect restoration activities. information on the Ecological Restoration health of water- ways and the Ecological restoration provides opportunities for the public to help out extent of NPS with a wide variety of projects, such as tree planting and bank pollutioh? stabilization in both urban and rural areas. Restoration efforts focus on degraded waters or habitats that have significant economic or ecological value. Educational Activities NPS pollution OCCUIG when Teachers can integrate NPS pollution curricula into their classroom water runs overland or through activities. The U.S. Environmental Protection Agency (EPA), federal the ground, picks up pollutants, and state agencies, private groups, and nonprofit organizations offer and deposits them in surface waters or introduces them into teachers a wide variety of materials. Students can start on an NPS groundwater control project in the primary grades and carry their work through to 'Ji the intermediate and secondary levels. Water Conservation Using technologies that limit water use in the bathroom, kitchen, laundry room, lawn, driveway, and garden can reduce the demand on existing water supplies and limit the amount of water runoff. More than 40 states now have some type of water conservation program to help citizens and businesses implement conservation practices. Government agencies, utilities, and hardware stores have information about different products that help households conserve water. http://www.epa.gov/OWOW/NPS/facts/point2.htm 9/27/01 I I I I I 1 I I I I I I LiflL. AUL I UL'A.. 11vU1LUL-L £11 1'UiLjJ'JLli1 )OUI-. LOiiUUi .. Household Management I Learning to limit NPS pollution at the household level can reduce the overall impacts of NPS pollution on water quality. Households, for example, can irrigate during cooler hours of the day, limit fertilizer applications to lawns and gardens, and properly store chemicals to reduce runoff and keep runoff clean. I Chemicals and oil should not be poured into sewers, where they can result in major water quality problems. Pet wastes, a significant source of nutrient contamination, should be disposed of properly. Households can also replace impervious surfaces with more porous materials. I Public Meetings and Hearings Decisions made during public hearings on stormwater permitting and town planning can determine a community's capability to manage NPS pollution over the long term. Laws or regulations may require federal, state, or local agencies to hold public hearings when permits are issued or when town plans are formed. Notices about hearings often appear in the newspaper or in government office buildings. Community Organizations Many communities have formed groups to protect local natural resources. These community-based groups provide citizens with information about upcoming environmental events in their watershed, such as ecological restoration, volunteer monitoring, and public meetings. Watershed-level associations are particularly effective at addressing a wide range of NPS pollution problems. Environmental Information on the Internet Citizens can obtain a tremendous amount of environmental data and educational material with a computer linked to the World Wide Web. EPA's site (http://www.epa.gov) on the World Wide Web provides up-to-date information on Agency activities and enables citizens to find out about air and water quality data in specific communities. EPA supports NPSINFO, a forum for discussion of NPS issues, including NPS education. Citizens with access to e-mail can subscribe to NPSINFO free of charge by sending an e-mail message to: listserver®unixmaiLrtpnc.epa.gov and include in the body of the message: subscribe NPSINFO (your first name) (your last name) Other federal, state, tribal, and local agencies, as well as businesses and nonprofit groups, also provide environmental information on the World Wide Web. RELATED PUBLICATIONS Additional fact sheets in the Nonpoint Pointers series (EPA-841-F-96-004) Clean Water in Your Watershed, Terrene Institute, Washington, DC, 1993 http://www.epa.gov/OWOW/NPS/facts/point2.htm 9/27/01 I I I I [ I I I I I J tip US L .5. LI 51¼..) JUL 5 LLL#fl¼.# 5455¼) 51 ¼..) LIL.L1 I Iii S lLPSIj¼.) £515 LILt 541 ¼¼.. ¼...&JSILA L'S Cleaner Water Through Conservation (EPA-841-B-95-002) Compendium of Educational Materials on the Water Environment, Alliance for Environmental Ed., Inc., Marshall, VA, 1992 EPA Journal, Vol. 17, No. 5, Nov/Dec 1991, (EPA-22k-1005) Environmental Resource Guide, Nonpoint Source Pollution Prevention, Air & Waste Management Assoc., Pittsburgh, PA Handle With Care, Terrene Institute, Washington,, DC, 1991 National Directry of Volunteer Environmental Monitoring Programs (EPA-841-B-94-001) The Quality of Our Nation's Water: 1994 (EPA-841-S-95-004) Xeriscape Landscaping (EPA-840-B-93-001) To order any of the above EPA documents, call or fax the National Center for Environmental Publications and Information. Tel (5 13) 489-8190 Fax (513) 489-8695 FOR MORE INFORMATON U.S. Environmental Protection Agency Nonpoint Source Control Branch Washington DC 20460 Office of Wetlands, Oceans & Watersheds Home I Watershed Protection Home EPA Home I Office of Water I Search I Comments (Contacts Revised January 21, 1997 URL: http://www.epa.gov/OWOWINPS/fIctsfpoint2.html http://www.epa.gov/OWOWINPS/facts/point2.htm 9/27/01 I I I Did you know 1 that at least 50% of water quality I problems In the U.S. result from NPS pollution? I I I Pointer No 4 EPA84 1-F-96-004D I The Nonpoint Source Management Program • • M I The Clean Water Act of 1972 helped clean up of many of our country's waters, often achieving dramatic improvements. Despite those successes, approximately 36 percent of the Nation's surveyed river miles, 37 percent of its surveyed lake acreage, and 37 percent of its s± surveyed estuarine square miles are not safe for basic uses such as swimming or fishing. States, territories, and tribes estimate that at least half of these impairments, as well as significant ground water contamination, are caused by nonpoint source (NPS) pollution, making it the Nation's leading source of water quality problems. To address these problems, Congress amended the Clean Water Act in 1987. Congress established the NPS Pollution Management Program under section 319 of the amendments. The program provides states, territories, and tribes with grants to implement NPS pollution controls described in approved NPS pollution management programs. In 1990, the U.S. Environmental Protection Agency (EPA) began awarding grants to states, territories, and tribes with approved programs. By 1991, all 50 states and the territories had received EPA approval; by 1995, 7 tribes also had received approval. Since 1990, recipients of 319 grants have directed approximately 40 percent of awarded funds toward controlling NPS pollution from agricultural lands. In addition, nearly one-quarter of the money was used for general assistance purposes, including funding for outreach and technical assistance. Effortsto control runoff from urban sources, septic systems, and construction also received significant funding under section 319, as did projects to manage wetlands and NPS pollution from forestry, habitat degradation, and changes to stream channels. As of 1995, EPA had awarded states, territories, and tribes $370 million under section 319 to implement NPS pollution control Section 319 Success Stories provides examples of how states, territories, and tribes chose to use section 319 funds. How Section 319 Works Assessment Reports I http://www.epa.gov/OWOW/NPS/facts/point4.htm 9/27/01 NPS pollution occurs when water runs over land orthrough the ground, picks up pollutants, i and deposits them in surface I waters or introduces them into In 1991, EPA established the National Monitoring Program to evaluate groundwater the effectiveness of NPS pollution control projects. Fourteen state- proposed projects will be evaluated over a 6- to 10-year period. The findings from this effort will help states, territories, and tribes develop more successful NPS pollution controls in other watersheds. I i\ULI1JL)iili. )OU.iL - -, All states, territories, and some tribes have met two basic requirements to be eligible for a section 319 grant, the first of which is to develop and gain EPA approval of a NPS pollution assessment report. In I the assessment report, the state, territory, or tribe identifies waters impacted or threatened by NPS pollution. The state, territory, or tribe also describes the categories of NPS pollution, such as agriculture, urban runofl or forestry, that are causing water quality. I Management Programs I To meet the second requirement a state, territory, or tribe must develop and obtain EPA approval of a NPS pollution management program. This program becomes the framework for controlling NPS pollution, given the existing and potential water quality problems described in the NPS pollution I assessment report. A well-developed management program supports activities with the greatest potential to produce early, demonstrable water quality results; assists in the building of long-term institutional capacity to address NPS pollution problems; and encourages strong interagency I coordination and ample opportunity for public involvement in the decision-making process. I How to Get Involved The addresses and telephone numbers of state and territory nonpoint source officials are listed in the I I'Tonpoint Source Water Quality Contacts Directory. These individuals can inform citizens about section 319 program activities in their home state or territory. They can also let citizens know how to become involved in the periodic updates of section 319 NPS assessments and NPS management i programs. RELATED PUBLICATIONS I Additional fact sheets in the Nonpoint Pointers series (EPA-841-F-96-004) I Managing Nonpoint Source Pollution: Final Report to Congress on Section 319 of the Clean Water Act (EPA-506/9-90) l Nonpoint Source Water Quality Contacts Directory, Conservation Technology Information Center, West Lafayette, Indiana I The Quality of Our Nation's Water: 1994 (EPA-841-S-95-004) I Section 319 National Monitoring Program Projects (EPA-841-S-94-006) Section 319 National Monitoring Program: An Overview, Water Quality Group, North Carolina State I University, March 1995 Section 319 Success Stories (EPA-841-S-94-004) I To order any EPA documents call or fax the National Center for Environmental Publications and Information. I Tel (513) 489-8190 I http://www.epa.gov/OWOW/NPS/facts/Point4.htm 9/27/01 'i-' ''-"r- •- - -- - - - _____Q - Fax (513) 489-8695 FOR MORE INFORMATION U.S. Environmental Protection Agency Nonpoint Source Control Branch Washington DC 20460 Office of Wetlands, Oceans & Watersheds Home I Watershed Protection Home EPA Home I Office of Water j5egch I Comments I Contacts Revised January 21, 1997 IJRL: http://www.epa.gov/OWOW/NPS/fcts/point4.htm1 http:f/www.epa.gov/OWOW/NPS/facts/po1nt4.htm 9/27/01 I I Did you know that by 2010, I almost one-half of the U.S. popula- tion will live near I coastal waters in regions that make I up only 10 percent of our countiys land areas? I I NPS pollution occurs when water runs over land or through the ground, picks up pollutants. I and deposits them in surface waters or introduces them into groundwater. k'roeCUflg t....SLa1 w1s LL Lll\•OrUiiL )OUzLA iLLiU.IUi1 I W .) I Pointer No. 5 EPA84 1-F-96-004E I Protecting Coastal Waters from Nonpoint Source Pollution I Coastal waters provide homes for an amazing array of plants and animals and are recreational havens for more than 180 million visitors each year. Yet, high levels of pollution prevented people from I , il7\ iL f swimming safely at coastal beaches on more than 12,000 occasions from 1988 through 1994, and the latest National Water Quality Inventory reports that one-third of surveyed estuaries (areas near the coast where I seawater and freshwater mixing occurs) are damaged Rapidly increasing population growth and development in coastal regions could be a source of even more coastal water quality problems in the future. A significant portion of the threats to coastal waters are caused by nonpoint source pollution (NPS). Major sources in coastal waters include agriculture and urban runoff. Other significant sources include faulty septic systems, forestry, marinas and recreational boating, physical changes to stream channels, and habitat degradation, especially the destruction of wetlands and vegetated areas near streams. In 1990, Congress passed the Coastal Zone Act Reauthorization Amendments (CZARA) to tackle the nonpoint source pollution problem in coastal waters. Section 6217 of CZARA requires the 29 states and territories with approved Coastal Zone Management Programs to develop Coastal Nonpoint Pollution Control Programs. In its program, a state or territory describes how it will implement nonpoint source pollution controls, known as management measures, that conform with those described in Guidance Specifying Management Measures for Sources of Nonpoint Pollution in Coastal Waters. If these original management measures fail to produce the necessary coastal water quality improvements, a state or territory then must implement additional management measures to address remaining water quality problems. Approved programs will update and expand upon NPS Management Programs developed under section 319 of the Clean Water Act and Coastal Zone Management Programs developed under section 306 of the Coastal Zone Management Act. I The coastal nonpoint program strengthens the links between federal and state/territory coastal zone management and water quality programs in order to enhance efforts to manage land management activities that degrade coastal waters and coastal habitats. State and territorial coastal zone agencies I and water quality agencies have coequal roles, as do the National Oceanic and Atmospheric Administration (NOAA) and the U.S. Environmental Protection Agency (EPA) at the federal level. I Coastal Nonpoint Pollution Control Programs In 1995, coastal states and territories submitted their coastal nonpoint programs to EPA and NOAA I http://www.epa.gov/OWOW/NPS/facts/point5.htm 9/27/01 I for review and approval. States and territories are scheduled to implement the first phase of their I approved program by 2004 and, if necessary, the second phase by 2009. Approved programs include several key elements, described below. I Boundary. The boundary defines the region where land and water uses have a significant impact on a states or territorys coastal waters. It also includes areas where future land uses reasonably can be expected to impair coastal waters. To define the boundary, a state or territory may choose a region I suggested by NOAA or may propose its own boundary based on geologic, hydrologic, and other scientific data. I Management Measures. The state or territory coastal nonpoint program describes how a state or territory plans to control NPS pollution within the boundary. To help states and territories identify I appropriate technologies and tools, EPA issued Guidance Specifying Management Measures for Sources of Nonpoint Pollution in Coastal Waters. This technical guidance describes the best available, economically achievable approaches used to control NPS pollution from the major categories of land I management activities that can degrade coastal water quality. States or territories may elect to implement alternative measurement measures as long as the alternative measures will achieve the same environmental results as those described in the guidance. Enforceable Policies and Mechanisms. States and territories need to ensure the implementation of the management measures. Mechanisms may include, for example, permit programs, zoning, bad actor I laws, enforceable water quality standards, and general environmental laws and prohibitions. States and territories may also use voluntary approaches like economic incentives if they are backed by appropriate regulations. I Final Approval and Conditional Approval ' In certain circumstances, NOAA and EPA may grant a program conditional approval for up to 5 years. Conditional approval provides a state or territory additional time to fully develop its management program while it begins initial program implementation. Conditional approval would include benchmarks for progress toward eventual full program development and approval. RELATED PUBLICATIONS Additional fact sheets in the Nonpoint Pointers series (EPA-841-F-96-004) I Coastal Nonpoint Pollution Control Program: Program Development and Approval Guidance (EPA- 841-B-93-003) I Global Marine Biological Diversity, Center for Marine Conservation, Island Press, Washington, DC, 1993 I Guidance Specifying Management Measures for Sources of Nonpoint Pollution in Coastal Waters (EPA-840-B-92-002) I The Quality of Our Nation's Water: 1994 (EPA-841-S-95-004) Testing the Waters V: Politics and Pollution at US Beaches, Natural Resources Defense Council, June I 1995 http://www.epa.gov/OWOW/NPS/facts/point5.htm 9/27/01 I iOiLiig Ct V aiCI hull l\ulipOLL 10 11 UJi I To order any EPA documents call or fax the National Center for Environmental Publications and Information. I Tel (513) 489-8190 I Fax (513) 489-8695 FOR MORE INFORMATION I U.S. Environmental Protection Agency I Nonpoint Source Control Branch I Washington DC 20460 I I I I I I I I I I I I Office of Wetlands. Oceans & Watersheds Home I Watershed Protection Home EPA Home I Office of Water I Search Comments I Contacts Revised January 21, 1997 URL: http://www.epa.gov/OWOW/NPS/facts/point5.htrnl http://www.epa.gov/OWOWNPS/facts/point5.htm 9/27/01 L. - L,LUi ALlX• S -- LA .J I Pointer No. 7 EPA84 1-F-96-004G I Managing Urban Runoff The most recent National Water Quality Inventory reports that runoff from urban areas is the leading source of impairments to surveyed 'estuaries and the third largest source of water quality impairments to I surveyed lakes. In addition, population and development trends indicate -- that by 2010 more than half of the Nation will live in coastal towns and cities. Runoff from these rapidly growing urban areas will continue to i --- degrade coastal waters. _______________ To protect surface water and ground water quality, urban development I and household activities must be guided by plans that limit runoff and Did you know reduce pollutant loadings. To this end, communities can address urban that because water quality problems on both a local and watershed level and garner I of Impervious the institutional support to help address urban runoff problems. surfaces such as pavement and How Urban Areas Affect Runoff I rooftops, a typical Increased Runoff. The porous and varied terrain of natural landscapes city block geii- like forests, wetlands, and grasslands trap rainwater and snowmelt and I erates 9 times allow it to slowly filter into the ground. Runoff tends to reach receiving more runoff than waters gradually. In contrast, nonporous urban landscapes like roads, a woodland area bridges, parking lots, and buildings don't let runoff slowly percolate into I of the same size? the ground. Water remains above the surface, accumulates, and runs off in large amounts. I Cities install storm sewer systems that quickly channel this runoff from NPS pollution occurs when roads and other impervious surfaces. Runoff gathers speed once it enters waler runs overland or through the storm sewer system. When it leaves the system and empties into a I the ground, picks up pollutants, and deposits them in surface stream, large volumes of quickly flowing runoff erode streambanks, waters or introduces them into damage streamside vegetation, and widen stream channels. In turn, this groundwater. will result in lower water depths during non-storm periods, higher than 1 4 normal water levels during wet weather periods, increased sediment loads, and higher water temperatures. Native fish and other aquatic life I cannot survive in urban streams severely impacted by urban runoff. Increased Pollutant Loads. Urbanization also increases the variety and amount of pollutants I transported to receiving waters. Sediment from development and new construction, oil, grease, and toxic chemicals from automobiles; nutrients and pesticides from turf management and gardening; viruses and bacteria from failing septic systems; road salts; and heavy metals are examples of pollutants generated in urban areas. Sediments and solids constitute the largest volume of pollutant loads to I receiving waters in urban areas. I When runoff enters storm drains, it carries many of these pollutants with it. In older cities, this polluted runoff is often released directly into the water without any treatment. Increased pollutant loads can harm fish and wildlife populations, kill native vegetation, foul drinking water supplies, and make I http://www.epa.gov/OWOW/NPS/facts/point7.htm 9/27/01 1iLL ILU iLiiOtj i - o . recreational areas unsafe. Point and Nonpoint Distinctions There are two different types of laws that help control urban runoff: one focusing on urban point sources and the other focusing on urban nonpoint sources. Urban point source pollution is addressed by the National Pollution Discharge Elimination System permit program of the Clean Water Act, which regulates stormwater discharges. Urban nonpoint source pollution is covered by nonpoint source management programs developed by states, territories, and tribes under the Clean Water Act. In states and territories with coastal zones, programs to protect coastal waters from nonpoint source pollution also are required by section 6217 of the Coastal Zone Act Reauthorization Amendments. Measures to Manage Urban Runoff Plans for New Development. New developments should attempt to maintain the volume of runoff at predevelopment levels by using structural controls and pollution prevention strategies. Plans for the management of runoff, sediment, toxics, and nutrients can establish guidelines to help achieve both goals. Management plans are designed to protect sensitive ecological areas, minimize land disturbances, and retain natural drainage and vegetation. Plans for Existing Development. Controlling runoff from existing urban areas tends to be relatively expensive compared to managing runoff from new developments. However, existing urban areas can target their urban runoff control projects to make them more economical. Runoff management plans for existing areas can first identify priority pollutant reduction opportunities, then protect natural areas that help control runoff, and finally begin ecological restoration and retrofit activities to clean up degraded water bodies. Citizens can help prioritize the clean-up strategies, volunteer to become involved with restoration efforts, and help protect ecologically valuable areas. Plans for Onsite Disposal Systems. The control of nutrient and pathogen loadings to surface waters I can begin with the proper design, installation, and operation of onsite disposal systems (OSDSs). These septic systems should be situated away from open waters and sensitive resources such as wetlands and floodplains. They should also be inspected, pumped out, and repaired at regular time intervals. I Household maintenance of septic systems can play a large role in preventing excessive system discharges. I Public Education. Schools can conduct education projects that teach students how to prevent pollution and keep water clean. In addition, educational outreach can target specific enterprises, such as service stations, that have opportunities to control runoff onsite. Many communities have I implemented storm drain stenciling programs that discourage people from dumping trash directly into storm sewer systems. I RELATED PUBLICATIONS Additional fact sheets in the Nonpoint Pointers series (EPA-841-F-96-004) Controlling Nonpoint Source Runoff From Roads, Highways, and Bridges (EPA-841-F-95-008a) Developing Successful Runoff Control Programs for Urbanized Areas (EPA-841-K-94-003) I http://www.epa.gov/OWOWINPS/facts/point7.htm 9/27/01 I I Li I I I 1 I I I A .J '.11 _) Economic Benefits of Runoff Controls (EPA-S-95-002) Fundamentals of Urban Runog Terrene Institute, Washington, DC, 1994 Guidance Specif'ing Management Measures for Sources of Nonpoint Pollution in Coastal Waters, Chapter 4 (EPA-840-B-92-002) Storm Water Fact Sheet (EPA-933-F-94-006) The Quality of Our Nations Water: 1994 (EPA-841-S-95-004) To order any of the above EPA documents call or fax the National Center for Environmental Publications and Information. Tel (513) 489-8190 Fax (513) 489-8695 FOR MORE INFORMATION U.S. Environmental Protection Agency Nonpoint Source Control Branch Washington DC 20460 Office of Wetlands, Oceans & Watersheds Home I Watershed Protection Home EPA Home I Office of Water I SearchI Comments I Contacts Revised January 21, 1997 TJRL: http://www.epa.gov/OWOWfNPS/fcts/point7.htm1 I I I http://www.epa.gov/OWOWINPS/facts/point7.htm 9/27/01 I I I I I I I I I I I I I I I I I I P I I I I I ATTACHMENT "F" I I I I I I I I I RESOURCES AND REFERENCES STORMWATER BEST MANAGEMENT PRACTICES The following are a list of BMPs may be used to minimize the introduction of pollutants of concern that may result in significant impacts to receiving waters. Other BMPs approved by the Copermittee as being equally or more effective in pollutant reduction than comparable BMPs identified below are acceptable. See Appendix B: Suggested Resources for additional sources of information. All BMPs must comply with local zoning and building codes and other applicable regulations. Site Design BMPs Minimizing Impervious Areas Reduce sidewalk widths Incorporate landscaped buffer areas between sidewalks and streets. Design residential streets for the minimum required pavement widths Minimize the number of residential street cul-de-sacs and incorporate landscaped areas to reduce their impervious cover. Use open space development that incorporates smaller lot sizes Increase building density while decreasing the building footprint Reduce overall lot imperviousness by promoting alternative driveway surfaces and shared driveways that connect two or more homes together Reduce overall imperviousness associated with parking lots by providing compact car spaces, minimizing stall dimensions, incorporating efficient parking lanes, and using pervious materials in spillover parking areas Increase Rainfall Infiltration Use permeable materials for private sidewalks, driveways, parking lots, and interior roadway surfaces (examples: hybrid lots, parking groves, permeable overflow parking, etc.) Direct rooftop runoff to pervious areas such as yards, open channels, or vegetated areas, and avoid routing rooftop runoff to the roadway or the urban runoff conveyance system Maximize Rainfall Interception Maximizing canopy interception and water conservation by preserving existing native trees and shrubs, and planting additional native or drought tolerant trees and large shrubs. Minimize Directly Connected Impervious Areas (DClAs) FINAL MODEL SIJSMP Page 36 0141 Jointly Developed by San Diego Co-Pennittees 2/14/02 I I I I III I Ii I I I Draining rooftops into adjacent landscaping prior to discharging to the storm drain I C Draining parking lots into landscape areas co-designed as biofiltration areas Draining roads, sidewalks, and impervious trails into adjacent landscaping I Slope and Channel Protection Use of natural drainage systems to the maximum extent practicable Stabilized permanent channel crossings I . Planting native or drought tolerant vegetation on slopes Energy dissipaters, such as riprap, at the outlets of new storm drains, culverts, conduits, or channels that enter unlined channels I Maximize Rainfall Interception Cisterns I • Foundation planting Increase Rainfall Infiltration I • Dry wells Source Control BMPs I Storm drain system stenciling and signage Outdoor material and trash storage area designed to reduce or control I rainfall runoff 0 Efficient irrigation system Treatment Control BMPs Biofilters C Grass swale Grass strip Wetland vegetation swale Bioretention Detention Basins . Extended/dry detention basin with grass lining Extended/dry detention basin with impervious lining I Infiltration Basins Infiltration basin Infiltration trench I . Porous asphalt Porous concrete Porous modular concrete block I I San Diego Co-Permittees 2/14/02 Page 37 of 41 I Wet Ponds and Wetlands Wet pond (permanent pool) Constructed wetland Drainage Inserts Oil,Water separator Catch basin insert Storm drain inserts Catch basin screens Filtration Systems Media filtration Sand filtration Hydrodynamic Separation Systems Swirl Concentrator Cyclone Separator FINAL MODEL SUSMP Page 38 of 41 Jointly Developed by San Diego Co-Permittees 2/14/02 APPENDIX B SUGGESTED RESOURCES HOW TO GET A COPY Better Site Design: A Handbook for Changing Center for Watershed Protection Development Rules in Your Community (1998) 8391 Main Street Ellicott City, MD 21043 Presents guidance for different model development 410-461-8323 alternatives. www.cwp.org California Urban runoff Best Management Los Angeles County Department of Public Works Practices Handbooks (1993) for Construction Cashiers Office Activity, Municipal, and Industrial/Commercial 900 S. Fremont Avenue Aihambra, CA 91803 Presents a description of a large variety of 626458-6959 Structural BMPs, Treatment Control, BMPs and Source Control BMPs Caltrans Urban runoff Quality Handbook: Planning California Department of Transportation and Design Staff Guide (Best Management P.O. Box 942874 Practices Handbooks (1998) Sacramento, CA 94274-0001 916-653-2975 Presents guidance for design of urban runoff BMPs Design Manual for Use of Bioretention in Prince George's County Stormwater Management (1993) Watershed Protection Branch 9400 Peppercorn Place, Suite 600 Presents guidance for designing bioretention Landover, MD 20785 facilities. Design of Stormwater Filtering Systems (1996) by Center for Watershed Protection Richard A. Claytor and Thomas R. Schuler 8391 Main Street Ellicott City, MD 21043 Presents detailed engineering guidance on ten 410-461-8323 different urban runoff-filtering systems. Development Planning for Stormwater Los Angeles County Management, A Manual for the Standard Urban Department of Public Works Stormwater Mitigation Plan (SUSMP), (May 2000) httix//dpw.co.la.ca.us/epd/ or http://www.888cleanLA.com Florida Development Manual: A Guide to Sound Florida Department of the Environment 2600 Land and Water Management (1988) Blairstone Road, Mail Station 3570 Tallahassee, FL 32399 Presents detailed guidance for designing BMPs 850-921-9472 Guidance Specifying Management Measures for National Technical Information Service U.S. Sources of Nonpoint Pollution in Coastal Waters Department of Commerce (1993) Report No. EPA-840-B-92-002. Springfield, VA 22161 800-553-6847 Provides an overview of, planning and design considerations, programmatic and regulatory aspects, maintenance considerations, and costs. Guide for BMP Selection in Urban Developed ASCE Envir. and Water Res. Inst. Areas (2001) 1801 Alexander Bell Dr. Reston, VA 20191-4400 (800)54 723 FINAL MODEL SUSMP Page 390141 I Jointly Developed by San Diego Co-Vernittees 2/14/02 I I I I 1 I I I] I I F I SUGGESTED RESOURCES HOW TO GET A COPY Low-Impact Development Design Strategies - Prince George's County, Maryland An Integrated Design Approach (June 1999) Department of Environmental Resource Programs and Planning Division 9400 Peppercorn Place Largo, Maryland 20774 http:Ilwr.co.pg.md. uslGovemment/DERIPPDlpg county/fidmain.htm Maryland Stormwater Design Manual (1999) Maryland Department of the Environment 2500 Broening Highway Presents guidance for designing urban runoff Baltimore, MD 21224 BMPs 410-631-3000 National Stormwater Best Management Practices American Society of Civil Engineers (BMP) Database, Version 1.0 1801 Alexander Bell Drive Reston, VA 20191 Provides data on performance and evaluation of 703-296-6000 urban runoff BMPs National Stormwater Best Management Practices Urban Water Resources Research Council of Database (2001) ASCE Wright Water Engineers, Inc. (303)480-1700 Operation, Maintenance and Management of Watershed Management Institute, Inc. Stormwater Management (1997) 410 White Oak Drive Crawfordville, FL 32327 Provides a thorough look at storm water practices 850-926-5310 including, planning and design considerations, programmatic and regulatory aspects, maintenance considerations, and costs. Potential Groundwater Contamination from Report No. EPAJ600/R-94/051, USEPA (1994). Intentional and Non-Intentional Stormwater Infiltration Preliminary Data Summary of Urban runoff Best http:IIwww.epa.gov/ost/stormwaterl Management Practices (August 1999) EPA-821-R-99-012 Reference Guide for Stormwater Best City of Los Angeles Management Practices (July 2000) Urban runoff Management Division 650 South Spring Street, 7th Floor Los Angeles, California 90014 http:/hwiw.lacity. oralsanlswmdl Second Nature: Adapting LA's Landscape for Tree People Sustainable Living (1999) by Tree People 12601 Mullholland Drive Beverly Hills, CA 90210 Detailed discussion of BMP designs presented to (818) 623-4848 conserve water, improve water quality, and Fax (818) 7534625 achieve flood protection. Start at the Source (1999) Bay Area Stormwater Management Agencies Association Detailed discussion of permeable pavements and 2101 Webster Street alternative driveway designs presented. Suite 500 Oakland, CA 510-286-1255 - FINAL MODEL SUSMP Page 40 of 41 I Jointly Developed by San Diego Co-Permittees 2/14/02 I I I H I I H I I I I SUGGESTED RESOURCES HOW TO GET A COPY Stormwater Management in Washington State Department of Printing (1999) Vols. 1-5 State of Washington Department of Ecology P.O. Box 798 Presents detailed guidance on BMP design for new Olympia, WA 98507-0798 development and construction. 360-407-7529 Stormwater, Grading and Drainage Control Code, City of Seattle Seattle Municipal Code Section 22.800-22.808, and Department of Design, Construction & Land Director's Rules, Volumes 1-4. (Ordinance Use 119965, effective July 5, 2000) 700 5th Avenue, Suite 1900 Seattle, WA 98104-5070 (206) 684-8880 httn:/lwww.ci.seattle.wa. us/dc! u/Codes/spdccode.h tm Texas Nonpoint Source Book - Online Module Texas Statewide Urban runoff Quality Task Force (1998)www.txnpsbook.orq North Central Texas Council of Governments 616 Six Flags Drive Presents BMP design and guidance information Arlington, TX 76005 on-line 817-695-9150 The Practice of Watershed Protection by Thomas Center for Watershed Protection R. Shchuler and Heather K. Holland 8391 Main Street Ellicott City, MD 21043 410-461-8323 www.cwa.org Urban Storm Drainage, Criteria Manual - Volume Urban Drainage and Flood Control District 3, Best Management Practices (1999) 2480 West 26th Avenue, Suite 156-B Denver, CO 80211 Presents guidance for designing BMPs 303-455-6277 FINAL MODEL SUSMP Page 41 0141 Jointly Developed by San Diego Co-Permittees 2/14/02 I I LI I I I I I ATTACHMENT "G" Li I I Li LI I I I I H I Owner Training Log Date: Storm Water Management Topic; Specific Training Objective: Location; Instructor: Attendee Rooster: Name Company Phone Li I I I I I I ATTACHMENT "H" I I I I I I I I I I I L~ Site Design &Landscape Planning SD10 Design Objectives 1 Maximize Infiltration ! Provide Retention I Slow Runoff Minimize Impervious Land Coverage Prohibit Dumping of Improper Materials Contain Pollutants Collect and Convey Descrij tion Each pro ect site possesses uiique topographic, hydrologic, and vegetative features, some of Which are more suitable for development than others. Integrating and incorporating appropriate landscape planning me-hodologie3 into the project design is the most effective action that can be done to mirimize surface ard groundwater contamination from stormwater Approach Landscap€ planning should ccuple consideration of land suitability for urban uses with onsideration of comminity goals anc projected growth. Project plan designs should conserve natural areas to the extent possible, maximize natural water storage and infiltration pporturites, and protect slo?es aLd channels. Suitabla Applications Appropriate applicaticris include retidential, ccmmercial and industrial areas planned for development or redevekpment. Design Considerations Design rec iirements far site cesign and landscapes planning should conform to applicable standard; and specifications cf agencies with jurisdiction and be consistent with applicable General Plan and Local Area Plan policies. SQA California Stormwater Quality Association January 21D 3 California Storm Nater BMP Handbook 1 of 4 New Developmert 3nd Redevelopment www.cabmph3ndbooks.com P SD10 Site Design & Landscape Planning Designing New Installations I Begin the development of a plan for the landscape unit with attention to the following general principles: Iit Formulate the plan on the basis of clearly articulated community goals. Carefully identify conflicts and choices between retaining and protecting desired resources and community growth. Map and assess land suitability for urban uses. Include the following landscape features in the assessment: wooded land, open unwooded land, steep slopes, erosion-prone soils, foundation suitability, soil suitability for waste disposal, aquifers, aquifer recharge areas, I wetlands, floodplains, surface waters, agricultural lands, and various categories of urban land use. When appropriate, the assessment can highlight outstanding local or regional resources that the community determines should be protected (e.g., a scenic area, I recreational area, threatened species habitat, farmland, fish run). Mapping and assessment should recognize not only these resources but also additional areas needed for their sustenance. I Project plan designs should conserve natural areas to the extent possible, maximize natural water storage and infiltration opportunities, and protect slopes and channels. I Conserve Natural Areas during Landscape Planning If applicable, the following items are required and must be implemented in the site layout during the subdivision design and approval process, consistent with applicable General Plan and I Local Area Plan policies: Cluster development on least-sensitive portions of a site while leaving the remaining land in I a natural undisturbed condition. is Limit clearing and grading of native vegetation at a site to the minimum amount needed to build lots, allow access, and provide fire protection. I w Maximize trees and other vegetation at each site by planting additional vegetation, clustering tree areas, and promoting the use of native and/or drought tolerant plants. I m Promote natural vegetation by using parking lot islands and other landscaped areas. Preserve riparian areas and wetlands. I Maximize Natural Water Storage and Infiltration Opportunities Within the Landscape Unit i Promote the conservation of forest cover. Building on land that is already deforested affects I basin hydrology to a lesser extent than converting forested land. Loss of forest cover reduces interception storage, detention in the organic forest floor layer, and water losses by evapotranspiration, resulting in large peak runoff increases and either their negative effects or the expense of countering them with structural solutions. I a Maintain natural storage reservoirs and drainage corridors, including depressions, areas of permeable soils, swales, and intermittent streams. Develop and implement policies and I I 2 of 4 California Stormwater BMP Handbook January 2003 New Development and Redevelopment www.cabmphandbooks.com I I Site Design & Landscape Planning SD10 I regulations to discourage the clearing, filling, and channelization of these features. Utilize I them in drainage networks in preference to pipes, culverts, and engineered ditches. Evaluating infiltration opportunities by referring to the stormwater management manual for the jurisdiction and pay particular attention to the selection criteria for avoiding I groundwater contamination, poor soils, and hydrogeological conditions that cause these facilities to fail. If necessary, locate developments with large amounts of impervious surfaces or a potential to produce relatively contaminated runoff away from groundwater I recharge areas. Protection of Slopes and Channels during Landscape Design I m Convey runoff safely from the tops of slopes. Avoid disturbing steep or unstable slopes. I m Avoid disturbing natural channels. Stabilize disturbed slopes as quickly as possible. I ra Vegetate slopes with native or drought tolerant vegetation. B Control and treat flows in landscaping and/or other controls prior to reaching existing I natural drainage systems. Stabilize temporary and permanent channel crossings as quickly as possible, and ensure that I increases in run-off velocity and frequency caused by the project do not erode the channel. Install energy dissipaters, such as riprap, at the outlets of new storm drains, culverts, conduits, or channels that enter unlined channels in accordance with applicable I specifications to minimize erosion. Energy dissipaters shall be installed in such a way as to minimize impacts to receiving waters. Line on-site conveyance channels where appropriate, to reduce erosion caused by increased I flow velocity due to increases in tributary impervious area. The first choice for linings should be grass or some other vegetative surface, since these materials not only reduce runoff velocities, but also provide water quality benefits from filtration and infiltration. If I velocities in the channel are high enough to erode grass or other vegetative linings, riprap, concrete, soil cement, or geo-grid stabilization are other alternatives. I is Consider other design principles that are comparable and equally effective. Redeveloping Existing Installations I 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. I January 2003 California Stormwater BMP Handbook 3 of 4 I New Development and Redevelopment www.cabmphandbooks.com I SD10 Site Design & Landscape Planning Redevelopment may present significant opportunity to add features which had not previously been implemented. Examples include incorporation of depressions, areas of permeable soils, and swales in newly redeveloped areas. While some site constraints may exist due to the status of already existing infrastructure, opportunities should not be missed to maximize infiltration, slow runoff, reduce impervious areas, disconnect directly connected impervious areas. Other Resources A Manual for the Standard Urban Stormwater Mitigation Plan (SUSMP), Los Angeles County Department of Public Works, May 2002. Stormwater Management Manual for Western Washington, Washington State Department of Ecology, August 2001. 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. I I I [ii I I I I I E I I Li r I I I 4 of 4 California Stormwater BMP Handbook January 2003 New Development and Redevelopment www.cabmphandbooks.com I I Efficient Irrigation SD-12 ` W-1c, Design Objectives Maximize Infiltration Provide Retention Slow Runoff Minimize Impervious Land Coverage Prohibit Dumping of Improper Materials r. SD-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. Redeveloping 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. LI I 2 of 2 California Stormwater BMP Handbook January 2003 New Development and Redevelopment www.cabmphandbooks.com I I R I I I I I I I I Ll I I P I I Storm Drain Sin 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 bundary of a development project. The marker should be placed in clear sight facing toward aflyone approaching the inlet from either side. All storm drain iilet locations should be icentifled 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 . SO A prohibitive language. Examples include "NO DUMPING - Calitomia Stormwater Quality Association January 2003 California Sto-mwater BMP Handbook 1 of 2 New Development and Redeveloment www.cabmphandbooks.com SD-13 Storm Drain Signage I DRAINS TO OCEAN" and/or other graphical icons to discourage illegal dumping. Im 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. I Note - 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 types and methods of application. I Redeveloping Existing Installations Various jurisdictional stormwater management and mitigation plans (SUSMP, WQMP, etc.) I 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. If the project meets the definition of "redevelopment", then the requirements stated under" designing new installations" above should be included in all project I design plans. Additional Information I 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 I 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 I oy Signage on top of curbs tends to weather and fade. is Signage on face of curbs tends to be worn by contact with vehicle tires and sweeper brooms. I Supplemental Information Examples I13 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 I A Manual for the Standard Urban Stormwater Mitigation Plan (SUSMP), Los Angeles County Department of Public Works, May 2002. I 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 I Control District, and the Incorporated Cities of Orange County, Draft February 2003. Ventura Countywide Technical Guidance Manual for Stormwater Quality Control Measures, I July 2002. I 2 of 2 California Stormwater BMP Handbook January 2003 I New Development and Redevelopment www.cabmphandbooks.com I Trash Storage Areas SD-32 Description Design Objectives Trash storage areas are areas where a trash receptacle (s) are Maximize Infiltration located for use as a repository for solid wastes. Stormwater Provide Retention runoff from areas where trash is stored or disposed of can be Slow Runoff polluted. In addition, loose trash and debris can be easily transported by water or wind into nearby storm drain inlets, Minimize Impervious Land channels, and/or creeks. Waste handling operations that may be Coverage sources of stormwater pollution include dumpsters, litter control, Prohibit Dumping of Improper and waste piles. Materials I Contain Pollutants Approach I This fact sheet contains details on the specific measures required to prevent or reduce pollutants in stormwater runoff associated with trash storage and handling. Preventative measures I including enclosures, containment structures, and impervious pavements to mitigate spills, should be used to reduce the likelihood of contamination. Collect and Convey 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 Design requirements for waste handling areas are governed by Building and Fire Codes, and by current local agency ordinances and zoning requirements. The design criteria described in this fact sheet are meant to enhance and be consistent with these code and ordinance requirements. Hazardous waste should be handled in accordance with legal requirements established in Title 22, California Code of Regulation. Wastes from commercial and industrial sites are typically hauled by either public or commercial carriers that may have design or access requirements for waste storage areas. The design criteria in this fact sheet are recommendations and are not intended to be in conflict with requirements established by the waste hauler. The waste hauler should be contacted prior to the design of your site trash collection areas. Conflicts or issues should be discussed with the local agency. Designing New Installations Trash storage areas should be designed to consider the following structural or treatment control BMPs: Design trash container areas so that drainage from adjoining roofs and pavement is diverted around the area(s) to avoid run-on. This might include berming or grading the waste handling area to prevent run-on of stormwater. S Q A Make sure trash container areas are screened or walled to California Stormwater prevent off-site transport of trash. Quality Association January 2003 California Stormwater BMP Handbook 1 of 2 New Development and Redevelopment www.cabmphandbooks.com Li I El I I El I I I I I I El I I I El SD-32 Trash Storage Areas in Use lined bins or dumpsters to reduce leaking of liquid waste . vi Provide roofs, awnings, or attached lids on all trash conta i n e r s t o m i n i m i z e d i r e c t precipitation and prevent rainfall from entering containers. vi Pave trash storage areas with an impervious surface to miti g a t e s p i l l s . vi Do not locate storm drains in immediate vicinity of the trash s t o r a g e a r e a . vi Post signs on all dumpsters informing users that hazardous m a t e r i a l s a r e n o t t o b e d i s p o s e d of therein. Redeveloping Existing Installations I Various jurisdictional stormwater management and mitig a t i o n p l a n s ( S I J S M P , W Q M P , e t c . ) define "redevelopment" in terms of amounts of additional imp e r v i o u s a r e a , i n c r e a s e s i n g r o s s floor area and/or exterior construction, and land disturbing ac t i v i t i e s w i t h s t r u c t u r a l o r I impervious surfaces. The definition of" redevelopment" mu s t b e c o n s u l t e d t o d e t e r m i n e whether or not the requirements for new development ap p l y t o a r e a s i n t e n d e d f o r redevelopment. If the definition applies, the steps outline d u n d e r " d e s i g n i n g n e w i n s t a l l a t i o n s " I above should be followed. Additional Information I Maintenance Considerations The integrity of structural elements that are subject to da m a g e ( i . e . , s c r e e n s , c o v e r s , a n d s i g n s ) must be maintained by the owner/operator. Maintenance ag r e e m e n t s b e t w e e n t h e l o c a l a g e n c y and the owner/operator may be required. Some agencies w i l l r e q u i r e m a i n t e n a n c e d e e d I restrictions to be recorded of the property title. If require d b y t h e l o c a l a g e n c y , m a i n t e n a n c e agreements or deed restrictions must be executed by the o w n e r / o p e r a t o r b e f o r e i m p r o v e m e n t plans are approved. I Other Resources A Manual for the Standard Urban Stormwater Mitigation P l a n ( S T J S M P ) , L o s A n g e l e s C o u n t y I Department of Public Works, May 2002. Model Standard Urban Storm Water Mitigation Plan (SIJS M P ) f o r S a n D i e g o C o u n t y , P o r t o f San Diego, and Cities in San Diego County, February 14, 2002. I Model Water Quality Management Plan (WQMP) for Count y o f O r a n g e , O r a n g e C o u n t y F l o o d Control District, and the Incorporated Cities of Orange C o u n t y , D r a f t F e b r u a r y 2003. I Ventura Countywide Technical Guidance Manual for Stor m w a t e r Q u a l i t y C o n t r o l M e a s u r e s , July 2002. I I 2 of 2 California Stormwater BMP Handbook January 2003 New Development and Redevelopment www.cabmphandbooks.com I