Loading...
The URL can be used to link to this page
Your browser does not support the video tag.
Home
My WebLink
About
CT 14-01; STATE MIXED USE 30; PRELIMINARY STORM WATER MANAGEMENT PLAN (SWQMP 15-08); 2015-08-26
--~ - .. . .; .. ·- • .. ., • • ... .. - - ..... E K&S ENGINEERJNG, INC. Planning Engineering Surveying ·-· ·-·--·-----· RECORD COPY °*(L t Jrl,J f> ~. Initial 7/q h8_ Date STORM WATER MANAGEMENT PLAN. ·-·--··-·-·--·-··-.. -· SWMP 15-08 FOR STATE MIXED USED 30 CT-14-01 3068 ST ATE STREET CARLSBADt CA 92008 PREPARED FOR STATE AND OAK CARLSBAD PROPERTIES LTD 10946 MADRONA DRIVE SIDNEY BC V8L 5P2 CANADA PREPARED BY: K&S ENGINEERINGt INC. 7801 MISSION CENTER COURT, SUITE JOO SAN DIEGO, CA 92108 JN 13-038 August 26, 20 I 5 780 l Mission Center Corn1, Suite I 00 . San Diego, California 92108 . (619)296-5565 . Fax (6 l 9)296-5564 TABLE OF CONTENTS Section 1.0 INTRODUCTION 2.0 PROJECT DESCRIPTION Figure 1 -Location Map 3.0 HYDROLOGIC UNIT CONTRIBUTION -----~igure 2 -Carlsbad Watershed Hydrologic Unit 3.1 BENEFICIAL USE Table 1 -Beneficial Uses 2 2 3 3 4 4 ---·------------··-------.. ----·--·----· 4.0 CHARACTERIZATION OF PROJECT RUNOFF 5 Figure 3 -Topographic Vicinity Map 5 4.1 POLLUTANTS OF CONCERN AND SOURCES 6 Table 2 -Anticipated and Potential Pollutants Generated by Land Use Type 6 4.1.A GENERAL POLLUTANT CATEGORIES 6 4.2 SOIL CHARACTERISTICS 8 FIGURE 4 SOIL HYDROLOGIC GROUP MAP 8 4.3 SITE HYDROLOGY 9 5.0 MITIGATION MEASURES TO PROTECT WATER QUALITY 10 5.1 Low IMPACT DEVELOPMENT (LID) SITE DESIGN BMPS ---·----10 5.1.1 PRIORITY DEVELOPMENT PROJECT LID BMP REQUIREMENTS 10 5.2 SOURCE CONTROL BMPS 11 5.3 TREATMENT CONTROL BMPs 12 TABLE 4 TREATMENT CONTROL BMP CATEGORIES 13 _____ Figure 5 -Construction BMP and Post Construction BMPS Site Map _________ _!_'!_ 5.5 SUMMARY 15 6.0 STORMW ATER BMP MAINTENANCE 16 6.1 MAINTENANCE MECHANISM 16 Table 5 -Permanent Treatment BMP Maintenance Schedule 17 7.0 FISCAL RESOURCES 18 ------------- Table 6 Permanent Treatment BMP Estimated Operation & Maintenance Costs 19 8.0 CONCLUSION 20 9.0 CERTIFJCA TION 21 - -ATTACHMENTS .,.,,.,u,,,....,,.,,..,.,,,0,,..-.,,..,,.m,.. ...... ,.L~au-•••mm "'""''•nmu,·n·rm.-,,-n····-••••••••• A HYDROLOGY STUDY REFERENCE B PERMANENT TREATMENT BMP INFORMATION BIORETENTION FACILITIES •-••••••••••••••••••••••••••••a,,..,..,,.,, .. , .... ,.,,,.,, •• ,.mmn,-, . ., C NUMERIC SIZING ... D CITY SUSMP FORMS E UMP EXEMPTION EXHIBIT - - .. .. .. ... .... .. - - ... .. .. E K&S' ENGINEEIUNG, INC. Planning Engineering Surveying STORM WATER MANAGEMENT PLAN (SWMP) . COPY OF THE APPROVED SWMP SHALL -BE KEPT ON FIELD AT ALL TIMES .. 780 I Mission Center Court, Suite I 00. San Diego, California 92108 . (619)296-5565 . Fax (619)296-5564 - - - ... - - 1.0 INTRODUCTION The California State Water Quality Control Board approved Order Number 2007-0001 (Order) on January 24; 2007.The Order outlines the stormwater discharge requirements for municipal stormwater systems, which drain "development" areas from watersheds within; I.) The County of San Diego, 2.) Incorporated cities of San Diego County, and 3.) San Diego Unified Port District. The City of Carlsbad is one of the municipal co-permittees identified in the order and, therefore, subject to its requirements. In general, the order requires that Best Management Practices (BMPs ): • • • • Control the post-development peak storm water storm discharge rates and velocities to maintain or reduce pre-development downstream erosion Minimize storm water pollutants of concern in urban runoff from new development through implementation of source control BMPs Remove pollutants of concern from urban runoff through implementation of structural treatment BMPs Include proof of a mechanism, to be provided by the project proposal, which will ensure ongoing long- term structural BMP maintenance. In addition, structural BMPs shall be located to infiltrate, filter, or treat the required runoff volume or flow (numeric sizing criteria) prior to discharge to any receiving water body supporting beneficial uses. The "numeric sizing criteria" is either volume or flow based. Specifically, volume based BMPs must be designed to infiltrate, filter, or treat the volume of runoff produced from a 24-hour -851h percentile storm event. This is approximately 0.6 inches of runoff for San Diego County. Similarly, flow based BMPs must be designed to infiltrate, filter or treat a flow rate of 0.2 inches of rainfall per hour. Note that the above "numeric sizing criteria" allows the option of infiltration, filtering or treatment of this volume/flow and relates only to water quantity. Retention or • detention of water volume/flow is not a requirement of the "numeric sizing criteria." .. - - - - This Water Quality Technical Report (WQTR) proposes to address the possible water quality impacts from the proposed grading and private improvements of State and Oak. It will define the potential BMP options that satisfy the requirements, identified in the following documents: I.) City of Carlsbad SUSMP January 14, 2011. 2.) County of San Diego Municipal NPDES Storm Water Permit (Order Number 2007-0001). The goal of this WQTR is to develop and implement the best available procedure policies of the Standards to insure to the maximum extent practicable that development does not increase pollutant loads from the project site and considers urban run-off flow rates, potential pollutants, and velocities. The WQTR also intends to insure the effectiveness of the Best Management Practices (BMPs) through proper maintenance that is based on long-term fiscal planning. This SWMP is subject to revisions by the engineer as needed due to site revisions or as directed by the City Engineer. Proposed project is within the hydromodification exempt area, per" Hydromodification Exemption Analyses for selected Carlsbad Watersheds" prepared by Wayne Chang dated June 10, 2013 See Attachment E According to the Storm Water Standards Questionnaire E-34 (see Appendix C of this report), the Project is subject to; • Priority Development Project (PDP) 2.0 PROJECT .DESCRIPTION The Project is located on North East comer of State Street and Oak Avenue in the City Of Carlsbad, County of San Diego, Figure 1 indicates the Project location. Currently there are six small residential buildings, with their corresponding driveways and landscaping. The proposed project consists of 33 Residential Condominiums and 5 commercial retail units, with landscape, hardscape, enclosed trash enclosure and parking areas. The total disturbed area will be 0.45acres, being 100% of the site. in general, approximately 63% of the site will drain to State Street, and 37% to Oak Avenue drainage systems. The northerly portion is drained to underground storm drain system at comer of Carlsbad Village drive and State which; eventually discharge to Buena Vista Lagoon. The southerly portion is drain to underground stonn drain system on Oak Avenue; which eventually discharge to Agua Hedionda Lagoon. On-site runoff will be treated with the use of flow thru planters "bio-retention" Bl\1P's to reduce or eliminate any pollutant generated by the project. 1. IWE DeS CHAlL\Ult Z. IIOIIM.\NDY LN 1JIIOUIIT.\INVll!W DIii 4. GNll'l!LD ST SITE LOCATION MAP Street lndex 5814C NTS 2 3.0 HVDROLOGJC UNIT CONTRIBUTION According to the State of California, Regional Water Quality Control Board, San Diego Hydrologic Basin Planning Area, the Project is located in the Buena Vista hydrologic area (HA) 904.20 within the Carlsbad Watershed hydrologic unit (HU). The sub-area is characterized by mostly urbanized commercial land. The cities of Carlsbad, San Marcos, and Encinitas are located entirely within the HU while it also contains ±27 square miles of the city of Escondido. Approximately 48% of the Carlsbad HU is urbanized. The dominant land uses are residential (29%), commercial/industrial (6%), freeways/roads (12%), agriculture (12%), and vacant/undeveloped (32%). Figure 2 indicates the Project general location within the HU. FIGURE2 Carlsbad Watershed Hydrologic Unit Approximate Project Location Constituents of concern are; indicator bacteria, sedimentation/siltation, total dissolved solids, metals and eutrophic indicators. The Agua Hedionda Lagoon, Buena Vista Lagoon, Buena Vista, and San Elijo lagoons are experiencing impairments to beneficial uses due to excessive coliform bacteria and sediment loading from upstream sources. San Elijo Lagoon is also suffering from problems relating to eutrophication. These problems are largely a result of urban run-off and sewage spills containing bacterial indicators. Poor tidal flushing of the lagoon is a primary cause of problem eutrophic conditions. These coastal lagoons represent critical regional resources that provide freshwater and estuarine habitats for numerous plant and animal species. Currently identification on the California 2006 303(d) list classifies, El Saito-Buena Vista Lagoon and Los Monos-Agua Hedionda Lagoon as impaired for bacterial indicator, Nutrients, Sedimentation/Siltation. The Project's 0.45 acres represents a very small percentage of the approximately 29,2 18 acres of the HSA and an even smaller percentage of the HU. The existing site contains 37% of impervious surface area. The proposed commercial retail units and residential condominiums will contain of 80% of impervious area. This project will utilize flow thru planters (bioretenions) Post Construction BMPs to treat any pollutants generated on-site. 3 Site splits into two water bodies, the northerly portion discharges to the Buena Vista Lagoon (904.21) located approximately 3, 1 OOfeet upstream and the southerly portion to Agua Hedionda Lagoon (904.31) located approximately 5,900 feet downstream. The project will not significantly alter the overall drainage pattern from the existing condition. 3.1 BENEFICIAL USE The beneficial uses of inland surface water, coastal waters and groundwater for this hydrologic sub-area and those downstream of the Project are identified in Table 1. The data contained in this table is extracted from Project Clean Water. TABLE 1 Beneficial water uses within the Carlsbad Watershed as designated in the State Water Resources Control Board's San Diego Region Basin Plan. Beneficial Uses Inland Surface Water Coastal Waters Reservoirs and Lakes Ground Water Municipal and Domestic Supply X X X Agricultural Supply X X X Industrial Service Supply X X X X Navigation X Contact Water Recreation X X X Non-Contact Water Recreation X X X Commercial and Sport Fishing X Warm Freshwater Habitat X X X Cold Freshwater Habitat X X Estuarine Habitat X Wildlife Habitat X X X Biological Habitats X Rare, Threatened, or End. X X Marine Habitat X Migration of Aquatic Organisms X Aquaculture X Shellfish Harvesting X Spawning, Reprod. and/or Early Develop. X Hydropower Generation 4 4.0 CHARACTERIZATION OF PROJECT RUN-OFF According to the California 2006 303(d) list published by the San Diego Regional Water Quality Control Board, the Buena Vista Lagoon (904.2) and Agua hedionda (904.31) and Pacific Ocean shoreline within the City Carlsbad beach are impaired water bodies. Figure 3 shows the approximate location of the Project and the surrounding topography. PACIFIC OCEAN Topographic Vicinity Map 5 4.1 POLLUTANTS OF CONCERN AND SOURCES There are no sampling data available for the existing site condition. In addition, the project is not expected to generate significant amounts of non-visible pollutants. However, the constituents listed in Table 2, which could affect water quality, commonly generate from similar developments. The nature of the project development can produce secondary pollutants of concern. Consider the pollutants -identified in Table 2 that aren't listed as pollutant stressors on the 303(d) List as being the secondary pollutants of concern. Implementation of source and treatment controls during and after construction limits or eliminates - ... .. .. ... ... - - - these poJlutants to the maximum practicable extent. The sources and affects of the primary and secondary pollutants of concern and other potential pollutants occurring on the project are identified below Table 2. TABLE2 Priority General Pollutant Categories Project Heavy Organic Trash Oxygen Oil& Bacteria Categories Sediments Nutrients Metals Compounds & Demanding Grease & Pesticides Debris Substances Viruses Commercial Development p(I) pPl X p(2) X p(5) X p(3) p(5) > 100,000 ft:2 Attached Residential X X X p(I) p(I) p X Development Restaurants X X X X p(I) X = anticipated P = potential ( 1) A potential pollutant if landscaping exists on-site. (2) A potential pollutant if the project includes uncovered parking areas . (3) A potential pollutant if land use involves food or animal waste products. (4) Including Petroleum hydrocarbons (5) Including solvents Anticipated and Potential Pollutants Generated by Land Use Type 4.1.A General Pollutant Categories The potential sources for the constituents of concern for the project could be, but are not limited to those listed below: o Sediments -Sediments are soils or other surficial materials eroded and then 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. o Nutrients -Nutrients are inorganic substances, such as nitrogen and phosphorus. They commonly exist in the form of mineral salts that are either dissolved or suspended in water. Primary sources of nutrients in urban run-off are fertilizers and eroded soils. Excessive discharge of nutrients to water bodies and streams can cause excessive aquatic algae and plant growth. Such excessive production, referred to as 6 - - - - - - - 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 the eventual death of aquatic organisms. o Metals -Metals are raw material components in non-metal products such as fuels, adhesives, paints, and other coatings. Primary source of metal pollution in storm water are typically commercially available metals and metal products. 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 concentrations, certain metals can be toxic to aquatic life. Humans can be impacted from contaminated groundwater resources, and bioaccumulation of metals in fish and shellfish. Environmental concerns, regarding the potential for release of metals to the environment, have already led to restricted metal usage in certain applications. o Organic Compounds -Organic compounds are carbon-based. Commercially available or naturally occurring organic compounds are found in pesticides, solvents, and hydrocarbons. 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 may also adsorb levels of organic compounds that are harmful or hazardous to aquatic life. o 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 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 conditions resulting in the growth of undesirable organisms and the release of odorous and hazardous compounds such as hydrogen sulfide. o 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 fats are examples of biodegradable organic compounds. Compounds such as 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. o Oil and Grease -Oil and grease are characterized as high-molecular weight organic compounds. Primary sources of oil and grease are petroleum hydrocarbon products, motor products from leaking vehicles, esters, oils, fats, waxes, and high molecular-weight fatty acids. 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. o Bacteria and Viruses -Bacteria and viruses are ubiquitous microorganisms that thrive under 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 decomposition of excess organic waste causes increased growth of undesirable organisms in the water. o 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 run-off containing toxic levels of its active component. 7 4.2 SOIL CHARACTERISTICS. Per the San Diego Hydrology Manual, Soil Hydrologic Groups map figure 4, the project area consists of soil group B. Soil group B soils have moderate infiltration rates when thoroughly wetted. They consist chiefly of soils that are moderately-deep to deep, moderately-well drained to well drained and moderately-coarse textured. Rate of water transmission is moderate. Group Bis classified as having a moderate infiltration rate. The USDA Web Soil Survey corroborates th is hydrologic soils group classification. FIGURE 4 Com1ty of San Diego Hydrology Manual Soil Hydrologic Groups 8 Legend Soll Groups Group A Groupe D Groupe GroupD Undelemilned D Data Unavailable ... - - 4.3 SITE HYDROLOGY Based on the most recent San Diego County Hydrology Manual, the Project's runoff coefficient ('C' factor) for the existing site value is C=0.51 and the value for the proposed site is C=0.67 There will be no diversion of flow for the development. The Project Hydrology Study contains detailed infonnation as to the methodology used in obtaining these results . 9 - - 5.0 MITIGATION MEASURES TO PROTECT WATER QUALITY To address water quality for the project, BMP's will be implemented. As a Priority Project, these categories require appropriate BMPs from the applicable categories below : • Low Impact Develpment BMPs • Source Control BMPs • Treatment Control BMPs In addition, incorporated into the Project are appropriate site design and source control BMPs for Standard Projects. 5.1 LOW IMPACT DEVELOPMENT (LID) SITE DESIGN BMPS Low Impact Development (LID) site design denotes a stonnwater management and land development strategy that emphasizes conservation and the use of on-site natural features integrated with engineered, small-scale hydrologic controls that closely reflect pre-development hydrologic functions. Projects address SUSMP objectives through the creation of a hydrologically functional project design that attempts to mimic the natural hydrologic regime. 5.1.1 Priority Development Project LID BMP Requirements Optimize Site Layout. The project site is previously developed, thereby negating the presence of natural areas. The site contains no natural resources or areas for conserving. There are no existing trees of major consequence within the Project site's disturbed footprint. Minimize impervious Footprint. -Not applicable. Disperse Runoff to adjacent Landscaping and IMP's. The project directs runoff from impervious surfaces towards landscaped areas. These measures disconnect the paved surfaces and roof areas from direct connection to MS-4. Minimize Soil Compaction in Landscape Areas.-Not applicable Convey Runoff safely from the tops of slopes.-The proposed project does not have existing, nor proposed slopes. Vegetated Disturbed soils with Native or drought tolerat vegetation.-Not applicable 10 - - - - - - - - 5.2 SOURCE CONTROL BMPS Source control BMPs, are selected, constructed, and maintained to comply with all applicable ordinances and guidance documents. The proposed Development will have the following category requirements: Specific Land Use Category BMPs a) Use Efficient Irrigation Systems & Landscape Design.-Landscape irrigation systems shall be of an efficient design with respect to each landscaped area's plantings specific water requirements. Maintenance of system installations on a regular and timely basis prevents over-watering and the transport of silts, sediments, fertilizers and pesticides into the storm drain system. Rain shut-off devices or moisture sensors shall be integral to the operation of the irrigation system to avoid unnecessary irrigation during wet weather conditions. Installing flow reducers or shut-off valves control loss of water due to unexpected pressure drops or other type of system compromise. Pest resistant, drought tolerant or native plants (per landscape architect plans) are used throughout the Project. b) Design Trash Storage Areas to reduce Pollution Coutributiou.-Trash storage areas shall: be paved with an impervious surface designed to prevent run-on from adjoining areas. Trash containers shall contain attached lids to prevent rainfall intrusion, lids will remain closed when not in use. c) Employ Integrated Pest Management Principles.-An integrated pest management (1PM) strategy is an ecosystem based pollution prevention strategy that focuses on long-term prevention of pests or their damage through a combination of techniques such as biological control, habitat manipulation, modification of cultural practices, and use of resistant plant varieties. Use of pesticides occurs only after monitoring indicates other 1PM methods have failed. Pest control materials selected and applied in a manner that minimize risks. Obtain more information on 1PM principles from the UC Davis website (http://www.ipm.ucdavis.edu/water/u/index.html). If fertilizers and pesticides are necessary, they are applied per manufacturer's minimum rates and guidelines to reduce the potential of pollutant transporting to the environment and the risk to human health or beneficial non-target organisms. The owner/developer/association will provide information on !PM practices, at the minimum relating to: the prevention of pests intrusion to buildings and landscaping using barriers, screens, and caulking; physical pest elimination techniques, such as, weeding, squashing, trapping, washing, or pruning out pests; relying on natural enemies to eat insect pests and the proper use of pesticides as a last line of defense. d) Provide Storm Water Conveyance System Stamping and Signage.-Any existing storm drain inlets affected by the project drainage ( if not already signed), as well as all on-site private inlets, will be posted with signage, stamped or stenciled (as appropriate to location) to provide notice against illegal dumping of pollutants with prohibitive language or graphics to the satisfaction of the City Engineer. These warnings shall be maintained for legibility throughout the development's existence. The owner will provide information to increase knowledge of tenants/employs/future owners regarding impacts of pollutants and urban runoff on receiving waters. 11 ... .. .. .. ... ... -- 5.3 TREATMENT CONTROL BMPS The primary pollutants of concern, bacteria, sediment, eutrophic conditions (nutrients) are considered pollutants that tend to associate with fine particles during treatment. Additionally, nutrients are classified as pollutants that tend to be dissolved following treatment (per Table 3). TABLE3 Pollutants That Tend Pollutants That Tend Coarse Sediment and to Associate with Fine Pollutant Trash Particles During to be Dissolved Following Treatment Treatment Sediment X X Nutrients X X Heavy Metals X Organic Compounds X Trash & Debris X Oxygen Demanding X Bacteria X Oil & Grease X Pesticides X Table extracted from the City of Escondido Storm water Management Requirements, January 14, 2011. Description of Pollutants of Concern Selected, treatment BMPs for this Project at this time is bioretention areas. The Post Construction BMP Site Map exhibit, Figure 5-B, contains locations, details and contribution areas, attachment C shows the numeric sizing for each basin of the project Per the selection matrix, Table 4, Bioretention facilities (LID) category offers a "High" treatment to the primary pollutants . 12 TABLE4 Treatment Control BMP Categories Pollutants Settling Wet High- Bio retention Basins Ponds Infiltration High-rate Trash Racks & of Concern Facilities (Dry and Facilities or Media rate media Hydrodynamic (UD) Ponds) Wetlands Practices(UD)* Filters blofilters filters Devices Coarse Sediment High High High High High High High High and Trash Pollutants that tend to associate with fine High High High High High Medium Medium High particles during treatment Pollutants that tend to be Medium Low Medium High Low Low Low Low dissolved following treatment Table extracted from the City of Carlsbad SUSMP, January 14, 2011. Treatment Control BMP Selection Matrix • - .... 13 - - - - - - ~[J'@®D@!Ju ©@!Jui:t[J'@D @oi:t@ DYiJcID~ l?o@ ®0 & [F)@®U ©@CiD®UD"llil©UD@CiD 00[Ml][F) IBou@ ffi'lu~[?) l?o~ ®0 00 14 ~ w w a:: ~ en I • I L K&S ENGINEERING, INC. Plarrr,g . Engileemg Su-veyng 7B01 u~sw, ,enlei (OUtl. s,,1, 100 San Ditgu. CA 91108 (619) 2%-5So\ r,, (619) 29s-'>So4 -.. -----~ -~ I' '--, '~ CHECK DAM SE-4 / -PRo:>osEO 10' RADIUS OCOICATION -------. ----.· -----,.---:---- STABILIZED CONSTRUCTION ENTRANCE/EXIT TC-1 --<t-- OAKAVENUE STABILIZED CONSTRUCTION ENTRANCE WITH STEEL PLATES TC-1 N.T.S. J PORTABLE SANITARY FACILITY WM-9 SECTION A SE-10 N.T.S. Fl.TER FABRIC -. ARE STACKED TlG!ll Y CATCH 8AS,1N '-CO.f.RSE AGGR£GATE 1r MIN. ".' ~GRAYEl SACS ,' I ~ 0 STORM DRAIN INLET PROTECTION DETAIL SE-10 NOT TO SCAI...£ LEGEND: DESCRIPTION CONSTRUCTION BMPS CODE (CASOA) I CHEO< DAM/STORM DRAIN lNlH PROTtCTIOO SE-<. SE-10 CURB INLET PROTtCTION I SILT FENCE SE - I --0-- 11 ·-1 1 11 -I I I -,~ ~SILT FENCE SE-1 STABILIZED CONSTRUCTIOO TC-1 ENTRANCE MATERIAL STORAGE WM-1,WM-2 WASTE COLLECTION WM-5 CONCRETE WASHOUT 'IIM-6 PORTABLE SANITARY FAQUTY WM-9 DIRECTION Of FLOW Pl)IIOINC HT. SlITl OR WOOO POST J6• HIGH --......, MAX. 1 I I I , I nL TER r ABRIC 1----.An~o SECURElY TO UPSTREAM SIDE Cf POST. ,c·xs· TREND! W/Ca.tPACT(D 8AO<F1Ll. CONCRETE WASHOUT WM-8 ALT. DETAIL SE1 TR£N01 WlTH CRA!w£l N.T.S. STD. DETAIL SE-1 lRENCH \\I TH NA TWE BAcxnu. WASTE COLLECTION WM-5 EXTRA STRENGTH OL TER FABRIC N[[O(D M THOJT V.,R( lit(.~ SUPPORT. N.l.S. _./ MATERIAL STORAGE -10· (lm) M»JMUM SPAQNG WITH 2.-REMO\Ol SECNMENT SHAU. 8£ DEPOSITED TO AN AREA THAT Mll NOT CCNlRIBUTE TO S([)IMENT ITT-SITE ANO CAN SE PERMANENTLY STABILIZED WM-1, WM-2 :i~~:,.~::Cf,,,ClNG WITHC>.IT WIRE SUPPCRT FENCE. SILTFENCE SE-1 NOT TO SCALE 3.-SILT F"ENCE SHAL.1 BE PLACED CW SLCPE CCWTOORS fO fAOUTATE MAxtMUM POODINC EFFlCENCY' r6ERIIEO Cai T AINM£N T AR!:A NOl(S: I. [XC£SS ANO WASTt CONCRE1£ SHAU. NOT 8£ WASHED INTO THE S1R[£T OR INTO A ~AINA.CI: SYSTEM. 2 fCA W"9-iCXJT CF CONCRETE: ANO MCRTAR PROOUCTS, A DESIGNATED C~TAINMENT FAOUTY CX" SUffiO(NT CAPAOTY TO RETAIN UOUID AND sa.J0 WASTE SHAU. BE 3. PR0\110£0 et: SITE. SLURRY FRCM COOrnETE ANO "5PHAI.. T SAW CUTTlNG SHAU. 8E VACUUMED ffi COHAIN£0, DRIED, PlocrD UP AHO DISPOSED a PRa:>ERI-Y. CONCRETE WASTE MANAGEMENT WM-8 NOT TO SCALE FIGURE 5-A I SH~ET I CITY OF CARLSBAD I SHE;TS I ENGINEERING DEPARTMENT SWMP FOR: 0 5 10 20 30 STATE MIXED USED 30 CT 14-01 ~t.~•!iit.rl.·~~~I ........ 1 JASON S GELDERT GRAPHIC SCALE: 1" 10· IF PLAN SIZE IS LESS THAN 24"x36", THIS IS A REDUCED COPY. SCALE PLAN ACCORDINGLY. PROJECT NO. CT 14-01 . ., ~ nNSH S\JRFACE: :t OJTF ALL P,P( CONNECT TO STREET 12· GlA'fl (J/8" TO S/8") OR Olli AP~O'iffi MATERIAi. OO'IINSPOJT Ct!ANC\IT IM.TH WAT£Rnon CAP ABO\'E POOOING DEPTlf DETAIL ONSITE FLOW THROUGH PLANTER NOT TO SCALE 1-w w 0:::: I-C/) w ~ Cl) J---__J ~~---~------~--~--------!: DMA DISTRIBUTION ~ OAK AVE STATE ST OMA 3; 900 SF O 4"'36 Sf U03:39Sf OMA1:1!00SFQ4-SF W1:300SF DMU 3625 SF O 4~45 SF LD4:200SF OMA2:1330SF@4""'S3Sf lD2:IIOSf OAK AVENUE DMAS: 1100 Sf O 4%= ... Sf LDS:119SF OMA6:1!00SF@4""'61lSF LD6:60SF ROOF PLAN OMA 7: 1IIIOSFQ4'K<4C Sf ow,. 8: 2000 SF O 4%< 80 Sf OW,. 9; 1650 Sf O 4%= 66 SF TOTAL: S625Sf TOTAL:9080SF 7801 M~sio,1 ;;.,,,~ ,.our\. \,;,le 100 Sor D"l•-CA 92108 (619) 196-5'>6, fa,: (619) 2%-,%4 lD 7'411 SF Ll)S:1MSf Lll!l:87SF LEGEND IT(M SYMeQL OM4 TO STATE SIBEEl Dl,O, TO OAK AVENUE >-w ....J ....J <( OOM-'SPOU1 ,· •ow 7.7' Q[ANOJT 'MTH WAl£RTlQH CAP ABOVE P~OING [l(PTH I Pl.ANTil'tGS r J" ROJNO ~ATE O'-'£RFl.OW S£T 2• ABOYE SOIL ~-Fi[5£PVOR-2-MIN $WOOTH CCf!CRETE SEAT CAP .!t...J'-+~~.,.>:·.:ft,<;'1'1~~ 11._ ~ .. DETAIL STREET FLOW THROUGH PLANTER NOT TO SCALE REQUIRED TREATMENT CONTROL BMP TABLE DESCRIPTION QUANTITY FLOW l>iR\J PLANTER (CLEANSING) 9 EA. 0 10 20 40 t...-i..-I GRAPHIC SCALE: 1 N 60 ! 20' BMP TABLE BMPDf BMP1Yl'E SYMBOL CASOA NO. QUANTITY DRAWING NO. SHEETNO.(S) INSl'ECTlON MAIITTENANCE CONS1RUCT1(l'I fREOUENCY fREOUENCY SIGN OFF TREATMENT CONTROL AND LOW INPACT DESIGN (LLD.) 0-®R.~~,+j~ SlREETR.OW __ ...,~.,;,:;~/. SOURCE CONTROL ® lllASH ['00 ENCtOSURE SITE DESIGI</ ® l.ANlSCAf'E EFACENT llRJGATION LJ CJ CJ I I -~--1 SITE PLAN TCJ:! 5 = 2 so.,o , so.12 IF PLAN SIZE IS LESS THAN 24"x36". THIS IS A REDUCED COPY. SCALE PLAN ACCORDINGLY. - [ , 1 1 ,SNEEDEC 2 TI.IES A YEN! ,SNEEDEO ,SNEEDED ,sNEEOEO .SNEEDED SWMP NO.:_Nl_A ___ _ W.INTENANCE AGREEMENT DOCUMENT: YES NO RECORDA.ncw.. NO.: ____ _ PARTY RESPONSIBLE FOR MAINTENANCE: NAME: STATE & OAK CAAIS8All ~ LTD. CONTACT:· DANIEi. COX ADORES5:10IM6 MADRON.A DR!VE SlllEV 8C 1181. 5"2 PHONE NOc2S0=5~1~=0445=------ Pl.AN PREPARED BY: NAME Iossa, ZtlllOAAODI COMPANY K&S EHGtlEERING ADORESS 1B01111$Sa, CENTE1< er. SUTE 100 SAN DEGO, CA 112109 PHONE N:>. (619) 29&6565 CERTFlCATION -==~-- BMPNOTES: 1. TIESE BMPS ARE MANDA.TORY TO BE NSTAUED PER IIAMJFACTURER'S RECOMloEND,t,'llONS OR n£SE PLANS. 2. NO a-W<GES TO 1HE PROl'OSEO BMPS ON lltS SHEETW!THOUT PRIOR APPROVAL FROM 1HE CITY ENGINEER. 3. NO SUBSTTTUT10NS TO lHE MAlERIAL OR lYPES OR PI.ANrHG 1Yl'ES wm«lUT PRIOR APPROVAL FROM ll£ CITY ENGINEER. 4. NO OCt»'NICf Wil BE GRNITED LMTL THE CITY INSPECflON STAFF HAS INSl'ECTED lllS PllO.ECTFORAPPROPRIATE BMP COIISTRUCTION NfJ NSTAI.J.ATION. FIGURE 5-B fSHml CITY OF CARLSBAD I SHE;TS I ~ ENGINEERING DEPARTMENT SWIIP FOR: STATE MIXED USED 30 CT 14-01 PROJECT NO. CT 14-01 % C ,,. ,_ ... C l J. . 5.5 SUMMARY By implementing the LID site design BMPs, source control BMPs and treatment BMPs, the production of the ... pollutants of concern will be limited. .. An effective Integrated Pest Management program preventing access of animal pests to trash receptacles and desirable environments limits the production of bacteria. Limited use of fertilizers and pesticides in landscaping keeps the introduction of nutrients to a minimum. With adequately established ground plantings prevents soil erosion there is a limited possibility for dissolved solids and sediments production from eroded soils. The limited use of fertilizers and the soil stabilization of permanent plantings and mulches covering erodible soil surfaces also limit the introduction of nutrient production leading to eutrophic conditions. Metals introduction to storm water flows are only potentially present during the construction phase of the Project as the usage of the -materials most commonly containing this pollutant are most prevalent then. - - - - All landscaped areas offer biofiltration for irrigation waters. Mulching, seeding and planting of these areas provide biofiltration of any necessary pesticide and fertilizer applications. Following manufacturer guidelines to avoid over-treatment of landscaping with pesticide & fertilizers will provide a limited occurrence of pollution from these products in the planted areas of the Project. The selected treatment BMPs in conjunction with the LID and source control BMPs provide limiting factors in the production of the pollutants of concern. Moreover, the proper use and adequate maintenance of the bio- retention areas, allow these effective treatment BMPs to work to their ultimate capabilities. 15 - - - - - ... - - - 6.0 STORMW ATER BMP MAINTENANCE The Project developer is financially responsible for the implementation of the erosion control measures during the construction phase in addition to the construction/installation of the post-development BMPs. The developer is responsible for the performance of the maintenance of the permanent BMPs. The applicant must ensure implementation and maintenance of the BMPs through the maintenance mechanism identified below. This mechanism must be acceptable to the City. The City Engineer will not consider structural BMPs "effective," and therefore will not accept stormwater BMPs as meeting the MEP standard, unless a mechanism is in place that will ensure ongoing long-term maintenance of all structural BMPs. Most of the permanent BMPs accrue minimal maintenance costs. Mulching, seeding and plantings are part of a continuing landscape maintenance program and can include the maintenance of the vegetated biofilter swale or bio-retention areas. Landscaping maintenance for permanent stabilization of graded areas and BMP maintenance will be the responsibility of the developer. Development of an Operation & Maintenance (O&M) Plan for the Project BMPs is the responsibility of the developer. The O&M Plan follows approval of this SWMP and prior to the issuance of any grading and/or building permits. The O&M Plan identifies the party responsible for management of the storm water BMPs, implementing a training program and duties, outlines maintenance frequency, routine service schedule, specific maintenance activities, specific costs encountered with operation & maintenance and any other necessary activities. Table 5 (next page) provides an outline of the BMP maintenance necessary for the permanent treatment BMPs. 6.1 MAINTENANCE MECHANISMS lnstaJlation and maintenance of the post-development BMPs is the responsibility of the developer under a Storm Water Maintenance Agreement (SWMA ). A security will be required ( of a form suitable to the City's determination) to back-up the SWMA in an amount determined by the City Engineer based upon costs contained in the O&M Plan. The SWMA remains in effect for the duration of the Project usage of the treatment BMPs identified therein. 16 - - - - .. .. - .. - .. - .. .. - - - '- - 'iJ'l:P@cIDUlJiJu@[Ji)U CID lMl IP lMlcID O[Ji)U@[Ji)©l[Ji)@@ ~@llu@©l llil D@ 'iI'cIDlIDD@ ® 17 j I i ' • • • • J. • i I i j TABLES Permanent Treatment BMP Maintenance Program A schedule of periodic maintenance should be implemented and modified, as needed, to insure effective operation of the indicated BMP's. As a guideline, a tentative schedule of maintenance frequency follov.,;_ The schedule is based on certain indicators outlined for a particular BMP. BMP ROUTINE ACTIONS MAINTENANCE FIELD MEASUREMENT FREQUENCY MAINTENANCE ACTlVnY INDIJ;:ATORS Height of vegetation. Ave,age height of vegetation Visual inspection of vegetation. lnspe,::t weekly and after Cut vPgetation •• ""quired. Bioretention Facility (grass) exceeds 4". rainy periods. (flow thru planterJ Assess adequate cover. Bare •pots appear in Visual inspection of lack of Assess growth on a monthly Rl'S""d v11getated ar,:,as as planted/ nmlched areas or less vegetative/ mulch cover. Record basis. Assess mulch cnverag!' ro:iuired. No later than than 70% coverage over entire locations to identify persistent on a monthly basis. Nov,:,mbPr. 5<'.arifv area for area. problem areas. r,:,s,...ding. R""'ppiy mulching as ro:iufred to cover hare spots. Inspe,::t for debris Del:iris or litter accwnulation. Visual inspection for trash. During routme site RPmove and properly dispose of accumulation landscape maintenanrr. trash, litter and debris. lnspe,::t for accwnulalion of Sediment is at or rear vegetation Visual inspection for sediment lnspe,::t monthly and after Remove arrumufoted sediment sediment or erosion of soil. height. Rill,; or gullies in topsoil depth. Visual inspection for rills each significant rainfa 11. when interf~rinp; with drainage and soil erosion flows. i - - .. - .. - ·- - - - 7.0 FISCAL RESOURCES The owner/developer of the project will be financially responsible for the construction and installation of the post-development BMPs and implementation of the LID site design and source control BMPs. Installation and maintenance of the post-development BMPs will be the responsibility of the property owner as designated in the Stonn Water Maintenance Agreement and the O&M Plan. The permanent responsibility of the post-development BMPs will remain with the owner or a designated association. The following table outlines the anticipated maintenance costs of permanent treatment BMPs . 18 .. .. .. .. • ... • • • • ·• - - - tJ!J'@cIDUITiJil@[Ji)U !ID [Ml~ [Ml cIDo [Ji)U@[Ji)cID[Ji)@@ ©@@U@ tJcID!IDD@ ® 19 i i • • • I l • • • • • J i TABLE6 PERMANENT TREATMENT BMP EsflMATED OPERATION AND MAINTENANCE (O&M) COSTS Pennanent BMPs constructed and installed for this project will necessitate continuous operation and maintenance when the project is complete. O&M cnsts arc ha..~ upon California Department of Transportation estimated costs for pilot BMP project utilizing prevailing wage rates. Below arc the itcmiz.ed costs. based on prevailing wage rates, of the project BMPs as shown on the Site Map. As identified in SWMP Section 7.0, Fi5t'411 Resources, the source for funding ofBMP operation and maintenance is the responsibility of the property owner(s)/developer. Post construction permanent BMP operation and maintenance costs include, but are not limited to the following: l,8aQB EQ!.!IP!,:!!;NT MATERIALS BMP QPERATIOt,! & MAINTENANCE ITEM TQTALCQST Per Hrs. B!m ~ .Im .Qm Rate ~ !§I! cw Tti!DIIl!l[ Rake, 1 Ton Truck, Fo~. ~hovel Safe~ l;!IORETENTION Ft&ILITY 12.0 43.63 ~ 0.5 19B.75 ~ Equipment. Bags, ~ 51,073 Hydroseeder i Seed, TtstiD,g & Disposal Q&MTQTAL $1,073 I I - - - ... ... .. • .. - .. ... - .. - - - 8.0 CONCLUSION This SWMP has shown LID site design, source control and treatment BMPs that should satisfy the requirements identified in the Order and Standards. This report insures, to the maximum extent practicable, that the development of the Project does not increase pollutant loads from the site . The effectiveness of these BMPs depends upon the proper operation procedure and effective maintenance on a definitive schedule identified within the O&M Plan. Long-term fiscal resources are necessary to provide the appropriate operation and maintenance activities to prolong the effectiveness of the identified BMPs. The developer is responsible for providing maintenance as outlined in the O&M Plan and agreed to in the PBMPMA. The provision of maintenance to BMPs is enforceable in accordance with the currently applicable City of Carlsbad ordinances, policies and regulations. It is shown that this project can meet the water quality objectives as outlined in Order R9-2007-0l with the BMPs identified on the single sheet BMP exhibit. An analysis has been performed to ensure that the site can accommodate the water quality BMPS. Therefore, it is anticipated tl1at the downstream waters will not be affected by the implementation of these BMPS . Proposed project is within the hydromodification exempt area, per " Hydromodification Exemption Analysis for selected Carlsbad Watersheds" prepared by Wayne Chang dated June 10, 2013 See Attachment E 20 .... . .., ... .. ·• ·• .... ·• ... - - 9.0 CERTIFICATION By affixing my seal and signature to the front of this report, I, Hossein Zomorrodi, certify the following: This Storm Water Management Plan has been prepared in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information within. To the best of my knowledge and belief, the information submitted is true, accurate, and complete . Furthermore, the data upon which recommendations, conclusions and decisions are based were derived from accepted engineering practices. This Stonnwater Management Plan has been prepared under my direction and supervision to comply with the requirements of the City of Carlsbad "Storm Water Standards Manual," issued January 14, 2011 and the SWRCB Order R9-2007-0001. ~ ...... -...... ·---.. --..... /0 ( 1 ls,,- P.E. 43235 21 - - - .. ATTACHMENTS .. .. ·• • .. .. .. .. - - - - 22 - - ... - .. ,_ - ATTACHMENT A HYDROLOGY STUDY REFERENCE .... - ... .. .. .... ... .. - K&S tf{_G'[[{~l?RUx·G, fN C. Planning Engineering Surveying HYDROLOGY STUDY FOR ST ATE MIXED USED 30 CT 14-01 3068 ST ATE STREET CARLSBAD, CA 92008 IN CITY OF CARLSBAD JN 13-038 August 24, 2015 780 I Mission Center Court, Suite I 00 . San Diego, California 92108 . (619)296-5565 . Fax (6 l 9)296-5564 - - ... - .. .. .. .. -., .. .. ' ... - .. - - TABLE OF CONTENTS I .SITE DESCRIPTION 2.HYDROLOGY DESIGN MODELS 3.HYDROLOGIC CALCULATIONS ............... APPENDIX A 4.TABLES AND CHARTS ................................ APPENDIX B 5.HYDROLOGY MAPS ................................... APPENDIX C 1801 Mission Center Court, Suite 100 . San Diego, California 92108 . (619)296-5565 . Fax (619)296-5564 - - ... ·• ... ... ... .. ... ... '. ... ... ... ·- - - CITY OF OCEANSIDE PACIFIC OCEAN 78 CITY OF VICINITY MAP NOT TO SCALE NOT TO SCALE Ul 0 u c::: a....<( O:::t Sheet3 - - - .. ... - .. - ... .. .. • - - 1. SITE DESCRIPTION EXISTING CONDITION EXISTING 0.41 AC PROPERTY CONSIST OF 3 LOTS WITH 7 BUILDINGS AND LANDSCAPING; LOCATED AT THE NE CORNER OF STATE STREET AND OAK AVENUE. THERE IS A HIGH POINT AT THE SOUTHERLY END OF STATE STREET AND DRAINAGE IS NORTH ON STATE AND WEST ON OAK AVENUE . APPROXIMATELY 62% OF THE SITE DRAINS TO STATE STREET AND 38% TO OAK AVENUE DRAINAGE SYSTEM. THE NORTHERLY PORTION DRAINS TO UNDERGROUND STORM DRAIN SYSTEM AT CORNER OF CARLSBAD VILLAGE DRIVE AND STATE STREET WHICH EVENTUALLY DISCHARGES TO BUENA VISTA LAGOON. THE SOUTHERLY PORTION DRAINS TO UNDERGROUND STORM DRAIN SYSTEM ON OAK AVENUE WHICH EVENTUALLY DISCHARGES TO AGUA HEDIONDA LAGOON. THIS PROJECT IS EXEMPT FROM HYDROMODIFICATION ACCORDING TO THE ANALYSIS FOR SELECTED CARLSBAD WATERSHEDS PREPARED BY CHANG CONSULTANTS DATED JUNE 10, 2013. PROPOSED CONDITION PROPOSED PROJECT CONSIST OF ONE BUILDING FOR COMMERCIAL RETAIL AND RESIDENTIAL CONDOMINIUM USE COVERING 80% OF THE SITE. THE RUNOFF FROM THIS PROJECT IS CONTROLLED THROUGH ROOF GUTTER AND DOWNSPOUT LOCATIONS IN ORDER TO TREAT STORM WATER AND TO MAINTAIN THE PRE AND POST DRAINAGE PATTERN AS CLOSE AS POSSIBLE . APPROXIMATELY 63% OF THE SITE WILL DRAIN TO STATE STREET AND 37% TO OAK AVENUE WITH THE USE OF FLOW THROUGH PLANTERS AND SIDEWALK UNDERDRAINS . 780 I Mission Center Court, Suite 100 . San Diego, California 92108 . (61,9)296-5565 . Fax (619)296-5564 Sheet4 j i i i _; ..... i .• i. '. -~ I ~ I ' .. I i -.& " EXISTING DATA OUTPUTS FLOW SOIL "c" INTENSITY STORM AREA RUNOFF TIME OF DISlf~CE CONCENTRATION NODE GROUP RUNOFF FACTOR EVENT (In/Hr) EVENT ACRES CFS (MINUTES) HIGHEST ELEV. 47.50' 85 B 0.51 6.85 100YR 0.104 0.363 5.00 1-2 LOWEST ELEV. 46.25' HIGHEST ELEV. 46.25 90 B 0.51 5.84 100YR 0.151 0.397 6.40 2-3 LOWEST ELEV. 44.52 SUBTOTAL 0.76 FLOW SOIL "c" INTENSITY STORM AREA RUNOFF TIME OF DIS(~CE CO~CENTRA TION NODE GROUP RUNOFF FACTOR EVENT (In/Hr) EVENT ACRES CFS MINUTES) HIGHEST ELEV. 47.70' 70 8 0.51 6.85 100YR 0.080 0.279 5.00 4-5 LOWEST ELEV. 46.30 HIGHEST ELEV. 46.30 91 B 0.51 5.65 100YR 0.079 0.179 6.72 5-6 LOWEST ELEV. 45.00 SUBTOTAL 0.46 en I u, - I -I , i ,. a • ~ • I • ' j j • j I ~ J i • I l i j l • I , j • PROPOSED DATA OUTPUTS FLOW SOIL "c" INTENSITY STORM AREA RUNOFF TIME OF DISlf~CE CONCENTRATION NODE GROUP RUNOFF FACTOR EVENT (In/Hr) EVENT ACRES CFS (MINUTES) HIGHEST ELEV. 47.75' 50 B 0.67 6.85 100YR 0.085 0.390 5.00 1-2 LOWEST ELEV. 47.50' HIGHEST ELEV. 41.so; 100 B 0.67 6.15 100YR 0.174 0.677 5.91 2-3 LOWEST ELEV. 44.60 SUBTOTAL 1.06 FLOW SOIL "c" INTENSITY STORM AREA RUNOFF TIME OF DISitt?E CONCENTRATION NODE GROUP RUNOFF FACTOR EVENT (In/Hr) EVENT ACRES CFS (MINUTES) HIGHEST ELEV. 45.91' 50 B 0.67 6.85 100YR 0.048 0.220 5.00 4-5 LOWEST ELEV. 45.66' HIGHEST ELEV. 45.66 100 B 0.67 6.85 100YR 0.107 0.491 5.00 5-6 LOWEST ELEV. 44.83' SUBTOTAL 0.71 - .. • • • .. .. .. ·• • • ·- 2. HYDROLOGY DESIGN MODELS A DESIGN METHODS THE RATIONAL METHOD IS USED IN THIS HYDROLOGY STUDY; THE RATIONAL FORMULA IS AS FOLLOWS: Q = CIA, WHERE: Q= PEAK DISCHARGE IN CUBIC FEET/SECOND• C = RUNOFF COEFFICIENT (DIMENSIONLESS) I= RAINFALL INTENSITY IN INCHES/HOUR (PER COUNTY RAINFALL ISOPLUVIALS) A= TRIBUTARY DRAINAGE AREA IN ACRES •1 ACRE INCHES/HOUR= 1.008 CUBIC FEET/SEC THE URBAN OVERLAND WATERSHED METHOD IS ALSO USED IN THIS HYDROLOGY STUDY; THE URBAN OVERLAND WATERSHED FLOW FORMULA IS AS FOLLOWS: T c=1.8(1. 1-C)(L) 5/[S(100)] 333 L = OVERLAND TRAVEL DISTANCE IN FEET S = SLOPE IN FTJFT Tc= TIME IN MINUTES B . DESIGN CRITERIA -FREQUENCY, 100 YEAR STORM. -LAND USE PER SPECIFIC PLAN . -RAIN FALL INTENSITY PER COUNTY OF SAN DIEGO 2003 HYDROLOGY DESIGN MANUAL C. REFERENCES -COUNTY OF SAN DIEGO 2003, HYDROLOGY MANUAL -COUNTY OF SAN DIEGO LATEST REGIONAL STANDARD DRAWING. -HAND BOOK OF HYDRAULICS BY BRA TER & KING, SIXTH EDITION . 7801 Mission Center Court, Suite 100 . San Diego, California 92108 . (619)296-5565 . Fax (619)296-5564 Sheet 7 - - APPENDIX A (3. HYDROLOGIC CALCULATIONS) .. .. • • • • . , • .. .. • .. ·• - 780 I Mission Center Court, Suite I 00 . San Diego, California 92108 . (619)296-5565 . Fax (619)296-5564 ·-Sheet 8 - - .. • .. .. • • -• .. ... - - EXISTING CONDITION STATE MIXED USED 30 13-038 San Diego County Rational Hydrology Program CIVILCADD/CIVILDESIGN Engineering Software, (c)1991-2012 Version 7.9 Rational method hydrology program based on San Diego County Flood Control Division 2003 hydrology manual Rational Hydrology Study Date: 07/10/15 Hydrology Study Control Ir.forrr,ation ********** Program License Serial Number €303 Rational hydrology study stoi:m event year is English (in-lb) input data Units used Map data precipitation entered: 6 hour, precipitation(inches) = 2.600 24 hour·precipitation(inches) = 4.400 P6/P24 = 59.1% San Diego hydrology manual 'C' values used 100.0 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.000 to Point/Station 2.000 **** INITIAL AREA EVALUATION**** Decimal fraction soil group A Decimal fraction soil group B Decimal fraction soil group C Decimal fraction soil group D [MEDIUM DENSITY RESIDENTIAL (7.3 DU/A or Less ) Impervious value, Ai= 0.400 Sub-Area C Value= 0.510 0.000 1. 000 0.000 0.000 Initial subarea total flow distance 85.DOO(Ft.) Highest elevation= 47.750(Ft.) Lowest elevation= 46.25D(Ft.) Elevation difference 1.SOO(Ft.} Slope= 1.765 % USER ENTRY OF INITIAL AREA TIME OF CONCENTRATION Time of Concentration= 5.00 minutes Rainfall intensity (I) = 6.BSO(In/Hr) for a 100.0 year storm Effective runoff coefficient used for area [Q=KCIA) is C = D.510 Subarea runoff= 0.363(CFS) Total initial stream area= 0.104(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 2.000 to Point/Station 3.000 **** IMPROVED CHANNEL TRAVEL TIME**** Upstream point elevation= 46.250[Ft.) Downstream point elevation 44.520(Ft.) Channel length thru subarea 90.0DO(Ft.} Channel base width O.OOO(Ft.) Slope or 'Z' of left channel bank= BO.DOD Slope or 'Z' of right channel bank= 80.000 Estimated mean flow rate at midpoint of channel Manning's 'N' = 0.023 Maximum depth of channel O.SOO(Ft.) Flow(q) thru subarea = 0.595(CFS) Depth of flow= D.083(Ft.), Average velocity Channel flow top width= 13.306(Ft.) Flow Velocity= l.OB(Ft/s) 0.595(CFS) 1.075(Ft/s) SHEETS ... .. - • • .. ·• .. ... .. .. ... .. ... .. ... -.. ·- - - - Travel time 1.40 min. Time of concentration= 6.40 min. Critical depth= 0.081(Ft.) Adding area flow to channel Rainfall intensity {I) = Decimal fraction soil group A Decimal fraction soil group B Decimal fraction soil group C Decimal fraction soil group D [MEDIUM DENSITY RESIDENTIAL (7.3 DU/A er Less ' J Impervious value, Ai= 0.400 Sub-Area C Value= C.510 5.845(In/Hr) for a 0.000 1. 000 0.000 O.CCC lOC.O year storm Rainfall ir.tensity = 5.E45(In/Hr) fer a 100.C year storm Effective rur.off coefficient used for total area (Q=KCIA) is C = C.510 CA= C.130 Subarea runoff= 0.397(CFS) for 0.15l(Ac.) Total runoff= 0.760(CFS) Total area= Depth of flow= 0.09l(Ft.), Average velocity= Critical depth= 0.089(Ft.) o. 255 {Ac. l 1.143 ( Ft/s) EXISTING CONDITION STATE MIXED USED 30 13-038 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 4.000 to Point/Station 5.000 **** INITIAL AREA EVALUATION**** Decimal fraction soil group A Decimal fraction soil group B Decimal fraction soil group C Decimal fraction soil group D [MEDIUM DENSITY RESIDENTIAL (7.3 DU/A or Less ) Impervious value, Ai= 0.400 Sub-Area C Value= 0.510 0.000 1. 000 0.000 0.000 Initial subarea total flow distance 70.000(Ft.) Highest elevation= 47.700(Ft.) Lowest elevation= 46.300(Ft.) Elevation difference l.400(Ft.} Slope= 2.000 % USER ENTRY OF INITIAL AREA TIME OF CONCENTRATION Time of Concentration= 5.00 minutes Rainfall intensity (I) = 6.850(In/Hr) for a 100.0 year storm Effective runoff coefficient used for area (Q=KCIA) is C = 0.510 Subarea runoff= 0.279(CFS) Total initial stream area= 0.0BO(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 5.000 to Point/Station 6.000 **** IMPROVED CHANNEL TRAVEL TIME**** Upstream point elevation= 46.300(Ft.) Downstream point elevation 45.000(Ft.) Channel length thru subarea 91.000(Ft.) Channel base width O.OOO(Ft.) Slope or 'Z' of left channel bank= 80.000 Slope or 'Z' of right channel bank= BO.DOD Estimated mean flow rate at midpoint of channel Manning's 'N' = 0.023 Maximum depth of channel 0.5DD(Ft.) Flow(q) thru subarea = 0.417(CFS) Depth of flow= 0.077(Ft.), Average velocity Channel flow top width= 12.319(Ft.) Flow Velocity= O.BB(Ft/s) 0. 417 (CFS) O.B80{Ft/s) SHEET 10 - ·- ... .. .. • .. .. • • .. • Travel time 1.72 min. Time of concentration= 6.72 min. Critical depth= 0.070(Ft.) Adding area flow to channel Rainfall intensity (I) = 5.659(In/Hr) for a Decimal fraction soil group A 0.000 Decimal fraction soil group B 1.000 Decimal fraction soil group C 0.COO Cecirnal fraction soil group D C. CGO [MECIUM DENSITY RESIDENTIAL (7.3 DU/A or Less Impervious val·c.e, Ai= 0.40C Sub-Area C Value= 0.51C 100.0 year storm Rair.fall ir.:tensity = 5. E59 (Ir:./Hr; for a 1cc. C year storrr1 Effective rur..off coefficier:.t used fer total area (Q=KCIA) is C = C.51C CA= C.C81 Subarea runoff= 0.179(CFS) for 0.079(Ac.) Total runoff= 0.459(CFS) Total area= Depth of flow= 0.080(Ft.), Average velocity Critical depth -0.073(Ft.) End of computations, total study area 0.159(Ac.) 0.90l(Ft/s) 0.414 (Ac. I EXISTING CONDITION ST A TE MIXED USED 30 13-038 7801 Mission Center Coort. Suite I 00. San Diego. California 92108 . (619)296-5565 . Fax (619)296-5564 SHEET 11 ... • ·• .. .. .. ... .. .. ... .... ... - - PROPOSED CONDITION STATE MIXED USED 30 13-038 San Diego County Rational Hydrology Program CIVILCADD/CIVILDESIGN Engineering Software, (c)l991-2012 Version 7.9 Rational method hydrology program based on San Diego County Flood Control Division 2003 hydrology manual Rational Hydrology Study Date: 07/10/15 ***'**'J.*** Hydrology Study Cantrel Information********** Program License Serial Nurr~er E303 Rational hydrology study stozm event year is English (in-lb) input data Units used Map data precipitation entered: 6 hour, precipitation(inches) = 2.600 24 hour precipitation(inches} = 4.400 P6/P24 = 59.1% San Diego hydrology manual 'C' values used 100.0 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.000 to Point/Station 2.000 **** INITIAL AREA EVALUATION**** Decimal fraction soil group A Decimal fraction soil group B Decimal fraction soil group C Decimal fraction soil group D [HIGH DENSITY RESIDENTIAL (24.0 DU/A or Less ) Impervious value, Ai= 0.650 Sub-Area C Value= 0.670 0.000 1. 000 0.000 0.000 Initial subarea total flow distance 50.000(Ft.) Highest elevation= 47.750(Ft.) Lowest elevation= 47.SOO(Ft.) Elevation difference 0.250(Ft.) Slope= 0.500 % USER ENTRY OF INITIAL AREA TIME OF CONCENTRATION Time of Concentration= 5.00 minutes Rainfall intensity (I) = 6.B50[In/Hr) for a 100.0 year storm Effective runoff coefficient used for area (Q=KCIA) is C = 0.670 Subarea runoff= 0.390(CFS) Total initial stream area= 0.0BS(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 2.000 to Point/Station 3.000 **** IMPROVED CHANNEL TRAVEL TIME**** Upstream point elevation= 47.SOO(Ft.) Downstream point elevation 44.600(Ft.) Channel length thru subarea 100.000(Ft.) Channel base width D.OOO(Ft.) Slope or 'Z' of left channel bank= 80.000 Slope or 'Z' of right channel bank= 80.000 Estimated mean flow rate at midpoint of channel Manning's 'N' = 0.015 Maximum depth of channel O.SOO(Ft.) Flow(q) thru subarea = 0.759[CFS) Depth of flow= 0.072(Ft.), Average velocity Channel flow top width= 11.SOl{Ft.) D.759(CFS) 1.837 (Ft/s) SHEET12 ·- - - ... .. .. .. ... -~ .. .. ... ... " ... ... -~ .. - - PROPOSED CONDITION ST ATE MIXED USED 30 13-038 Flow Velocity= 1.84 (Ft/s) Travel time 0.91 min. Time of concentration= 5.91 min. Critical depth= 0.089(Ft.J Adding area flow to channel Rainfall intensity (I) = Decimal fraction soil group A Decimal fraction soil group B Cecimal fraction soil group C Decimal fraction soil group C [HIGH DENSITY RESIDENTIAL (24.C DU/A or Less Impervious value, Ai= C.65C Sub-Area C Value= 0.670 6.152(In/HrJ for a 0.000 1. 000 c.coc C.000 lCC.O year storm Rainfall intensity= E.152(In/Hr; for a lCC.C year storm Effective runoff coefficient used fer total area (Q=KCIA) is C = 0.670 CA= 0.174 0.677(CFS) for 0.174(Ac.) Subarea runoff= Total runoff= Depth of flow= Critical depth= l.D68(CFS) Total area= O.D82(Ft.), Average velocity= 0. 259 (Ac.) 2.000(Ft/s) 0 .102 (Ft.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 4.000 to Point/Station 5.000 **** INITIAL AREA EVALUATION**** Decimal fraction soil group A 0.000 Decimal fraction soil group B 1.000 Decimal fraction soil group C 0.000 Decimal fraction soil group D 0.000 [HIGH DENSITY RESIDENTIAL (24. 0 DU/A or Less ) Impervious value, Ai = 0.650 Sub-Area C Value = 0. 670 Initial subarea total flow distance 50.000(Ft.l Highest elevation= 45.910(Ft.) Lowest elevation= 45.660(Ft.) Elevation difference 0.250(Ft.) Slope= 0.500 % USER ENTRY OF INITIAL AREA TIME OF CONCENTRATION Time of Concentration= 0.10 minutes Calculated TC of 0.100 minutes is less than 5 minutes, resetting TC to 5.0 minutes for rainfall intensity calculations Rainfall intensity (I) = 6.850(In/Hr) for a 100.D year storm Effective runoff coefficient used for area (Q=KCIA) is C = 0,670 Subarea runoff= 0.220(CFS) Total initial stream area= 0.04B(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 5.000 to Point/Station 6.000 **** IMPROVED CHANNEL TRAVEL TIME**** Upstream point elevation= 45.660(Ft.) Downstream point elevation 44.83D(Ft.) Channel length thru subarea 100.0DO(Ft.) Channel base width O.ODO(Ft.) Slope or 'Z' of left channel bank= Slope or 'Z' of right channel bank= Estimated mean flow rate at midpoint BO.ODD 80.000 of channel Manning's 'N' = 0.015 Maximum depth of channel Flow(q) thru subarea = 0.500(Ft.) 0.4b6{CFS) 0.466(CFS) SHEET13 - - .. - .. ... .. • .. .. • ... ·• • .. - - - Depth of flow= 0.076(Ft.), Average velocity 1.017(Ft/s) Cha:r:nel flow top width= 12.107(Ft.) Flow Velocity= 1.02(Ft/s) Travel time 1.64 min. Time cf concentration= 1.74 min. Critical depth= 0.073(Ft.) Adding area flow to channel Calculated TC of 1. 739 minutes is less than 5 minutes, resettir:ig 'TC to .5. C minutes for re.inf.all inter:.si ty calculations Rainfall intensity (I) = E.85C(Ir../Hr) fer a 100.0 year stcrm Decimal fraction soil grou:i_:: A C.COC Decimal fraction soil group E 1.COC Ceci1nal fractic:r: soil group C C. CCC Decimal fraction soil group D a.COO [HIGH DENSITY RESIDENTIAL (24.C CU/A or Less ) Impervious value, Ai= 0.650 Sub-Area C Value= 0.670 Rainfall intensity= 6.BSO(In/Hr) for a 100.0 year storm Effective runoff coefficient used for total area (Q~KCIA) is C ~ 0.670 CA~ 0.104 Subarea runoff= 0.491(CFS) for 0.107(Ac.) Total runoff = 0. 711 (CFS) Total area = Depth of flow= 0.089(Ft.), Average velocity Critical depth -0.087(Ft.) End of computations, total study area 0.155(Ac.) 1.131 (Ft/s) 0.414 (Ac.) PROPOSED CONDITION STATE MIXED USED 30 13-038 7801 Mission Center Court, Suite JOO. San Diego. California 92108. (619)296-5565 . Fax (619)296-5564 SHEET 14 - - - -APPENDIXB (4. TABLES AND CHARTS) .. ·• • • - 7801 Mission Center Court, Suite 100. San Diego, California 92108. (619)296-5565. Fax (619)296-5564 ·- - Sheet 15 ·- - - - - - - - :~: ·2...-fA°'.rl, . ~t '-.. \ ' ' ., Table 7-l·L \'alues.of A~' for Circu!ar Chnnnc~Js in. dw Forn,uJn, -··-~- d J ·00 _l_w -" .0 .1 .000 07 ,, .p.&.O . ·-G .3 .090 7 ••• • J ,5.6 .5 .232 .6 .SU • 7 .388 .8 . .f5' .s .(9·.f1 1.0 ,.,a t j . D ""' de.pth of w11,t<•t· ti -= di:lnwtrr of channel ¥ LC-W - .Ol .02 .03 .o~ ,05 -·-1· . -.... _-. .0007 4 • .OOl lS·.00222 .00007 .00031 .0118 .01(2 .Olu7 .OJ.!15 .022!i .0,H8 .0492 .0537' .0585 .003-1 .oor.o .J027 .J08U .J 153 .1218 .1033 .I?OS • J 779 .1864, .1929 .239 .2.n· .255 .203 .271 .319 .327 r335 .3-43 .350 .'395 . A0:2: .40tl AJ.6 A22 .468 · .416! f..t68 ..ti3 .<1? •. (.9'6 .49i ..t.98 .-l.08 ·"98, l - .oo .07 - .Q0328 .0045 .0257 .029) .0080 .0738- .1284 .1352 .2005 .2082 .279 .281 .358 .366 .429 A35 .(81 .48.5 .496··•11 .,9-:t I .08 I b .00ft04 · .0077 5 .03:,?7" .0366 .0703 .0849 .14.ZO .14!>0 .2J.00 .2238 .29S .303 .373 .380 A.t I. .4,4"1 .488 .4·91 • .f.8{}; .(8.! -~"-'~~liUll!r..l'-.~':;-.,z:z.C::ii::::!::.''::•:!l"n~"'r"':r~•-~"r•:t.~..:a;;-Aa,c:..:.~~~~.;i;,..~,-~~ . -·· ---. ~ " C • . Sheet 16 ( ' - - - - - D:J±!_ t>'f \;' I H r>tl { l . C J 1>1. ul C 1>1, r:l11J u l1 ) S\.~t. l [ net l in 1-ci) c,.H· lron J.. l \JIili n = Cornif•.ntcd Mu:tl (iiot l.iru·c.1 Corrurrte.d Meu.J (;?} (s®oth uplu.l\ qu1.nerB.nine) CDTTUf.tlt:e.d Mi,ta.l (:l) ($11100t:h asphr:lt h,:,lf lin.in1) Co:rruJ&.t6d Meet cl ( smoot:h u.phLlt htl l Hn~) Co.ncret:• RCP ClL)' {rew:er) .ubestos C•t.n'l~ Pv,r_ Orf.in Tile; (tr,rrli cotu) Cut• in-pla.Cf. Pipe; R.einfore:ed Conc.r1,tl!; ilo;,. :l. Open Cha.nnel i. {l) , , Unlined Cli.y Leu S"11d h. Revettt:.d GT'&.Vel Rock Pipe" a..nd Wirt su,ked Con ere, tc, c:. l..ined , Ccn(c:re.te (pourt,d) Air{ :a~own Mort1.r Cl) J.sphaltic Concrete or Rituminous Pl&nt Mb. d. Vei,tated (S) Grus lined, aa.intained Gra1s 1111cl 'll'eeds Gn.ss lined with concre.te. low flow ch&nni;l s. h.vement md !iu'l:ters {l.) Concrete. lit1JIDino1a .. lP11ll.t-llli>tE>tl) ltouf.hnt.i ~· Cod' Hcl,.;,i · ( i,) O.OH O.CIH .o:n 0.024 0.021 o.ou 0 .012: D.012 o.on: O.Oll O.OlS O.OlS 0.034 0.0,3 0.02D o.o:;o 0.040 0.02S 0.025 o.-oi4 O.Ol6 0.038 .o:ss .04S .032 O.Ol~ 0.016 - - - - - - - Typ<-of Watton,ay_ 4 .. Oepressed t,c,dian~ (10:1 ~lopo\l) Earth (w1tho111 growth) , Earth (with £rowth) ,Gravel 1,,w9h n~ s s Codf 1 ci t.n1 ( r ). 0.04o 0.050 0.055 a. Mi nor st rt.ams (surface width at flood stage< 100 ft) (1) Fairly regula, section (a) SomE grass and weeds, i ftt lt> or no br·ush (b) Dense growth of weeds, depth of flow mater i a 11 y greater than weed he I ght ( c) Semi, weeds, 11 ght brush on banks (d) Soml!e weeds, heavy bru!!h on banks (e) For tre~.s wlt·hin channel with branche~ submerged a;t high :.tage, incn,aH. all above values by 0.015 (2) · Irregular section, with pools, slight channel meander Channels (a) to (t) above, increase al 1 values by 0.015 (3) Mountain Hreams: no v<ogetation in chan,1el, banks usually ste;ep, trees and brush along banks submerged at high stage (a) Bottom, gr;.ve,l, cobbles ano fe,w boulcien (b) Bottom, cobbl~ with large boulders b. Flood plains (adjacemt to natural streams) (1) Pasture, no brush (a) Short grass (b) High grass {2) Cultlvated.ar5as; (a) No crop (b) Mature row crops (c) Mature field crops (3) · Heavy weeds, scattered brush (4) Light brush and t:rees: (5) Medium to de~se brush (6) Dense wi J lows Ci.030 0 ,, Cl40 0.040 o. 060 o. 050 0.06() 0.030 0.040 (7) Cleared land with tree, stumps, 100-150 per acre (8) Heavy st.and of tilllbE.r, little undet"growth o.o4o o.o4o 0.050 0.050 0.060 0.090 o. 170 0.060 (a) Flood deoth below branches (b) Flood depth reaches branches 0.110 0. 140 APPENDIX XV, Sheet 18 i i San Diego County Hydrology Manual Date: June 2003 • j I i Section: Page: Table 3-1 RUNOFF COEFFICIENTS FOR URBAN AREAS Land Use Runoff Coefficient "C" Soil Type NRCS Elements Coun Elements % IMPER A B Undisturbed Natural Terrain (Natural) Permanent Open Space O* 0.20 0.25 Low Density Residential (LOR) Residential, 1.0 DU/A or less 10 0.27 0.32 Low Density Residential (LOR) Residential, 2.0 DU/A or less 20 0.34 0.38 Low Density Residential (LDR) Residential, 2.9 DU/ A or less 25 0.38 0.41 Medium Density Residential (MOR) Residential, 4.3 DUI A or less 30 0.41 0.45 Medium Density Residential (MDR) Residential, 7.3 DU/ A or less 40 0.48 ~ Medium Density Residential (MOR) Residential, 10.9 DU/A or less 45 0.52 0.54 Medium Density Residential (MDR) Residential, 14.5 DU/A or less 50 0.55 0.58 High Density Residential (HOR) Residential, 24.0 DU/A or less 65 0.66 8 High Density Residential (HOR) Residential, 43.0 DU/A or less 80 0.76 0.77 Commercial/Industrial (N. Com) Neighborhood Commercial 80 0.76 0.77 Commercial/Industrial (G. Com) General Commercial 85 0.80 0.80 Commercial'lndustrial (O.P. Com) Office Professional/Commercial 90 0.83 0.84 CommerciaJIIndustrial (Limited I.) Limited Industrial 90 0.83 0.84 CommerciaJ./Industrial General I. General Industrial 95 0.87 0.87 C 0.30 0.36 0.42 0.45 0.48 0.54 0.57 0.60 0.69 0.78 0.78 0.81 0.84 0.84 0.87 3 6 of26 D 0.35 0.41 0.46 0.49 0.52 0.57 0.60 0.63 0.71 0.79 0.79 0.82 0.85 0.85 0.87 *The values associated with 0% impervious may be used for direct calculation of the runoff coefficient as described in Section 3.1.2 (representing the pervious runoff coefficient, Cp, for the soil type), or for areas that will remain undisturbed in perpetuity. Justification must be given that the area will remain natural forever (e.g., the area is located in Cleveland National Forest). ~DU/ A = dwelling units per acre a, • • !t.NRCS = National Resources Conservation Service _.. (0 3-6 ' - - .. ... ... I I ... ... San Diego County Hydrology Manual Date: June 2003 Section: Page: 3 12 of26 Nate that the Initial Time of Concentration should be reflective of the general land-use at the upstream end of a drainage basin. A single lot with an area of two or less acres does not have a significant effect where the drainage basin area is 20 to 600 acres. Table 3-2 provides limits of the length (Maximum Length (LM)) of sheet flow to be used in hydrology studies. Initial Ti values based on average C values for the Land Use Element are also included. These values can be used in planning and design applications as described below. Exceptions may be approved by the "Regulating Agency" when submitted with a detailed study. Table 3-2 MAXIMUM OVERLAND FLOW LENGTH (LM) & INITIAL TIME OF CONCENTRATION (Ti) Element* DU/ .5% 1% 2% 3% 5% 10% Acre LM Ti LM Ti LM Ti LM Ti LM Ti LM Ti Natural 50 13.2 70 12.5 85 10.9 100 10.3 100 8.7 100 6.9 LDR 1 50 12.2 70 11.5 85 10.0 100 9.5 100 8.0 100 6.4 LDR 2 50 11.3 70 10.5 85 9.2 100 8.8 100 7.4 100 5.8 LDR 2.9 50 10.7 70 10.0 85 8.8 95 8.1 100 7.0 100 5.6 unP .d. 1 ,fl 1 fl 'J 7fl a;:;: Q(\ Q 1 Q.,_. 7 Ii! 1 no h7 1nn ' 'l MDR 7.3 50 9.2 65 8.4 80 7.4 95 7.0 100 6.0 100 4.8 I MDR 10.9 50 8.7 65 7.9 80 6.9 90 6.4 100 5.7 100 4.5 \.,ff'lD 1A , '-'f\ ~ ') iC I: '7 A 2() t::. .,_. Q(\ ,:;. (\ 1 (\(\ ,A 1 (1(1 ,1 'l HDR 24 50 6.7 65 6.1 75 5.1 90 4.9 95 4.3 100 3.5 I HOR 43 50 5.3 65 4.7 75 4.0 85 3.8 95 3.4 100 2.7 N.Com 50 5.3 60 4.5 75 4.0 85 3.8 95 3.4 100 2.7 G.Com 50 4.7 60 4.1 75 3.6 85 3.4 90 2.9 100 2.4 0.P./Com 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 General I. 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 3-12 Sheet20 I, I I 33'1S'- 2.6 32"45' . I ---· 'I I' I,, , I I fn t I '( I 1 :: I I -1. t "·· ••• •, · ... ·· .. ·-. · .. ··. ·· ... -33'30' I Ii ·· .. \'··. · .... /' :···. r\ t_. .. 7,._ ( .. / ..... ,,,.,..~ ', ,I-, \ ---· ~ ( '.)~;;)f.'.,i~".::: . ~••" \~':,,··· ... ~· ,. ... (~,-~-,:.:_------···· •', ..... ') '--. ~ -~ !i '.\t \ ,. ... ! ·.·.'. :i .• ··········-·· g ,, J:) f \\\ ... • .f .~~ ~ ---t--;--* ___ a2""5' a.1'00' 32"30' County of San Diego Hydrology Manual Rainfall lsopluvials 1~ Year Rainfall Event-6 Ho~ 190l)lwlal (lnct,es) 3 0 3 Mlln Sheet 21 ~ SES 4.4 32'45' • -- 32'30' t I ~ I)) ''(') I •' ·-+--i-i-1-i-,----'-' -__ ...__ ___ ... -~--- t _J -----·--·J; -· --33'30' ·, ....... ::~'$ County of San Diego Hydrology Manual • Rainfall lsopluvials t 00 Vear R•tnfall Event -24 Hours leophNlsl (Inches) +N :*£:=.~=:;m~~-.====:u ~ ~-,~,o-·~~ ~&MtN.-....... --..... ,,. ..... _,~...,,.,....~ .. S"6t,O ...... B =-.,-::::_-•........,....,. .. ._.....,_....,_...~ .............. .....,.. _ _....,.....,... ... ,,,_..._ ..... s 3 0 3 Mllff Sheet 22 ~ 33" 9'3Z"N 33" 9'JO'N I 467SJO N A Soil Map-San Diego County Area, California (Oak Street) 467SSO I 467550 467560 I 467560 Map Scale: 1:474 f pmted on A landstape (11" x 8.5"1 sheet .-----====:::::,----------....:===========Meters 0 5 10 20 30 467570 467570 ------c:::=====-------------============feet o 20 ~ oo m Map projectt)n: Web MerciltDr ComerCXX>rdifaes: WGS84 Edge tk::s: UTM lone llN WGS84 467580 467590 Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 467600 467610 467620 -I 3/19/2015 Page 1 of 3 33" 9'32"N 33" 9' lO'N Map Unit Description: Marina loamy coarse sand, 2 to 9 percent slopes-San Diego County Area, California San Diego County Area1 California MIC-Marina loamy coarse sand, 2 to 9 percent slopes Natural Resources Conservation Service Map Unit Setting National map unit symbol: hbdz Mean annual air temperature: 57 to 61 degrees F Farmland classification: Prime farmland if irrigated Map Unit Composition Marina and similar soils: 85 percent Minor components: 15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Marina Setting Landform: Ridges Down-slope shape: Linear Across-slope shape: Linear Parent material: Eolian sands derived from mixed sources Typical profile H1 -0 to 10 inches: loamy coarse sand H2 -10 to 57 inches: loamy sand, loamy coarse sand H2 -10 to 57 inches: sand, coarse sand H3 -57 to 60 inches: H3 -57 to 60 inches: Properties and qualities Slope: 2 to 9 percent Depth to restrictive feature: More than BO inches Natural drainage class: Somewhat excessively drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Salinity, maximum in profile: Nonsaline (0.0 to 2.0 mmhos/cm) Available water storage in profile: Moderate (about 8.7 inches) Interpretive groups Land capability classification (irrigated): 3s Land ca abilit classification nonirri ated : 4e Hydrologic Soil Group: B Minor Components Carlsbad Percent of map unit: 5 percent Web Soil Survey National Cooperative Soil Survey Oak Street 3/19/2015 Page 1 of2 Sheet24 Map Unit Description: Marina loamy coarse sand, 2 to 9 percent slopes-San Diego County Area, California Chesterton Percent of map unit: 5 percent Corralitos Percent of map unit: 5 percent Data Source Information Soil Survey Area: Survey Area Data: Natural Resources Conservation Service San Diego County Area, California Version 8, Sep 17, 2014 Web Soil Survey National Cooperative Soil Survey Oak Street 3/19/2015 Page 2 of 2 Sheet25 Soil Map-San Diego County Area, California (Oak Street) MAP LEGEND MAP INFORMATION Area of Interest (AOI) D Area of Interest (AOI) Solis D Soil Map Unit Polygons ~ Soil Map Unit Lines • Soil Map Unit Points Special Point Features U> 181 ~ 0 X ' .. A • ~ 0 V + .. • .. • ~ ~ JI/ USDA Natural Resources Conservation Service Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot @ Spoil Area 0 Stony Spot 4) Very Stony Spot V Wet Spot 4 Other *' Special Line Features Water Features ,,..._, Streams and Canals Transportation ...... Rails rWlil Interstate Highways -US Routes ,,-.,, Major Roads ,......,. Local Roads Background Aerial Photography Web Soil Survey National Cooperative Soil Survey The soil surveys that comprise your AOI were mapped at 1 :24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale . Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: http://websoilsurvey.nrcs.usda.gov Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below . Soil Survey Area: Survey Area Data: San Diego County Area, California Version 8, Sep 17, 2014 Soil map units are labeled (as space allows) for map scales 1 :50,000 or larger. Date(s) aerial images were photographed: May 3, 2010-Jun 19, 2010 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background Imagery displayed on these maps. As a result. some minor shifting of map unit boundaries may be evident. Soil Map-San Diego County Area, California Map Unit legend San 019go County A~ Califotnta CCM3l!) I Milp Unit ·Name f Acn!!S in AOJ j MIC I Marina loamy coarse sand, 2 to [ 9 percent slopes 0.4 Totals for Area of Interest -r--0.4 , -------l ------------- Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey Oak Street Pen:ent of AO! 100.0%1 100.0% I ' ----------- 3119/2015 Page 3 of 3 Sheet27 APPENDIXC (5. HYDROLOGY MAP) 780 I Mission Center Court, Suite I 00 . San Diego, CaJifornia 92108 . (6 19)296-5565 . Pax (6 19)296-5564 Sheet28 ---s 44.52LE ~oa°·76CFS j l 3 ..... w w 0:::: ..... Cl) w ..... <( ..... Cl) ~ l .. ·- CaJCRf ----EXJST. NClOO FfN(C .. . . ---- (m•41.90) . ., / 1. MXl) (£Na / I .. ~~/ / .. qJHRS PRl< 9CN .. 45.00LE l ~000.46CFS (X. SMH o114.84RIW l6.09IE --l- .. .., "' EXIST 24' DWY \ (01ST. BUWNG) /ITT•'6.57) '0 .. -, ·rn,r ~·ii~.' !Mil~~[?) -jilll© ... 5 - 46.30 ----,----, (EXlST. CARACC) OAK AVENUE EX. 42' INTERC£PTCR SEWER PER DM.f l6~2 SI-C(l 4 ---s s s --- -<t-- (rnsr. CARA(£} · . [)IJST. Mm ..-?OLf ___ _ 0 (r.OST. SHfllJ (DIST BUILJJfNC) .. \'.j ~ " ~ ~ r I . I . . s-- DRAINAGE LEGEND AREA (ACRES) COEFFICIENT FACTOR l OD· YR RUNOFFS @::::__ 46_25 NODE NUMBER ELEVATION_/ ---91 LF ---- BASIN BOUNDARY FLOW D ISTANCE ABBREVIATIONS: HE HIGHTEST ELEVATION LE LOWEST ELEVATION 0 5 10 20 t..-..• I GRo\PHIC SCALE: 1" -10' IF PLAN SIZE IS LESS THAN 24"x36" THIS IS A REDUCED COPY. SCALE PLAN • ACCORDINGLY. E~E~=,~~ HYDROLOGY PLAN 7801 Mission Cenl" c....t. S..I< 100 Sm Oieqo, CA 92108 (619) 296-5565 fa,: (619) 296->564 FOR: STATE MIXED USED 30 EXISTING CONDITION JN 13-036 .I 1 ~ <( I. ·- J I I L --ct-- OAK AVENUE --------------- DRAINAGE LEGEND AREA (ACRES) COEFFICIENT FACTOR 1 DO• YR RUNOFFS @:::::_ 4625 NODE NUMBER ELEVATION__,,/ .,1 -11 -11 -11 -,t -J l -11 • ----91LF ---- ABBREVIATIONS: BASIN BOUNDARY FLOW DISTANCE HE HIGHTEST ELEVATION LE LOWEST ELEVATION STATE STREET RUNOFF TO OAK AVENUE 0 5 10 t..-t..• 20 I i GRAPHIC SCALE: 1. -10' IF PLAN SIZE IS LESS THAN 24":,:36", THIS IS A REDUCED COPY. SCALE PLAN ACCORDINGLY. E~EN=I~~ HYDROLOGY PLAN 7801 Wissioo Ctnter Coor!. Suile 100 Sm Diego, C~ 92108 (619) 296-5565 Fm: (619) 296-5564 FOR: STATE MIXED USED 30 PROPOSED CONDITION .lN 13-038 $HEET3G I I I I tii I ~ I ~, liic.i> I I I I I r I · _ _1_ ---- -- -~ ------ ---1--- 1 OAK AVENUE EXISTING CONDfflON tii UJ a: 1-U) wJ ~I I I I I. I L---~----~-----OAKAVENUE ----T PROPOSED CONDfflON LEGEND DESCRIPTION ONSITE IMPERVIOUS AREA 20 I j 0 5 10 t...w..- GRAPHIC SCALE: 1" -10' IF PLAN S1ZE IS LESS THAN 24"x36", THlS IS A REDUCED COPY. SCALE PLAN ACCORDINGLY. E~E~~,~~ HYDROLOGY PLAN 7801 llission Cenler c...t, Suit< 100 Sm Diego, CA 92108 (619) 296-5565 Fax: (619) 296-5561 FOR: STATE MIXED USED 30 IMPERVIOUS AREAS JN 13-038 SHEET'1 ATTACHMENTB PERMANENT TREATMENT BMP INFORMATION Bioretention Facilities Bioretention Description The bioretention best management practice (BMP) functions as a soil and plant-based filtration device that removes pollutants through a variety of physical, biological, and chemical treatment processes. These facilities normally consist of a grass buffer strip, sand bed, ponding area, organic layer or mulch layer, planting soil, and plants. The runoffs velocity is reduced by passing over or through buffer strip and subsequently distributed evenly along a ponding area. Exfiltration of the stored water in the bioretention area planting soil into the underlying soils occurs over a period of days. California Experience None documented. Bioretention has been used as a storm.water BMP since 1992. In addition to Prince George's County, MD and Alexandria, VA, bioretention has been used successfully at urban and suburban areas in Montgomery County, MD; Baltimore County, MD; Chesterfield County, VA; Prince William County, VA:, Smith Mountain Lake State Park, VA; and Cary, NC. Advantages • Bioretention provides stormwater treatment that enhances the quality of downstream water bodies by temporarily storing runoff in the BMP and releasing it over a period of four days to the receiving water (EPA, 1999). • The vegetation provides shade and wind breaks, absorbs noise, and improves an area's landscape. Limitations • The bioretention BMP is not recommended for areas with slopes greater than 20% or where mature tree removal would January 2003 califomla Stormwater BMP Handbook New Development and Redevelopment www.cabmphandbooks.com TC-32 Design Considerations • Soll for lnfillration • T ribulary Area • Slope • Aesthetics • Environmental Side-effects Targeted Constituents 0 Sediment • 0 Nutrients • 0 Trash • 0 Metals • 0 Bacteria • 0 Oil and Grease • @ Organics • Legend (RerrJCWal BrttcfivenessJ • Low • High • Medium 1 of8 - • • .. ... TC-32 Bioretention be required since clogging may result, particularly if the BMP receives runoff with high sediment loads (EPA, 1999). • Bioretention is not a suitable BMP at locations where the water table is within 6 feet of the ground surface and where the surrounding soil stratum is unstable. • By design, bioretention BMPs have the potential to create vecy attractive habitats for mosquitoes and other vectors because of highly organic, often heavily vegetated areas mixed with shallow water. • In cold climates the soil may freeze, preventing runoff from infiltrating into the planting soil. Design and Sizing Guidelines • Tue bioretention area should be sized to capture the design storm runoff. • In areas where the native soil permeability is less than 0.5 in/hr an underdrain should be provided. • Recommended minimum dimensions are 15 feet by 40 feet, although the preferred width is 25 feet. Excavated depth should be 4 feet. • Area should drain completely within 72 hours. • Approximately 1 tree or shrub per 50 ft2 of bioretention area should be included. • Cover area with about 3 inches of mulch. Construction/Inspection Considerations Bioretention area should not be established until contributing watershed is stabilized. Performance Bioretention removes stormwater pollutants through physical and biological processes, including adsorption, filtration, plant uptake, microbial activity, decomposition, sedimentation and volatilization (EPA, 1999 ). Adsorption is the process whereby particulate pollutants attach to soil ( e.g., clay) or vegetation surfaces. Adequate contact time between the surface and pollutant must be provided for in the design of the system for this removal process to occur. Thus, the infiltration rate of the soils must not exceed those specified in the design criteria or pollutant removal may decrease. Pollutants removed by adsorption include metals, phosphorus, and hydrocarbons. Filtration occurs as runoff passes through the bioretention area media, such as the sand bed, ground cover, and planting soil . Common particulates removed from stormwater include particulate organic matter, phosphorus, and suspended solids. Biological processes that occur in wetlands result in pollutant uptake by plants and microorganisms in the soil. Plant growth is sustained by the uptake of nutrients from the soils, with woody plants locking up these nutrients through the seasons. Microbial activity within the soil also contributes to the removal of nitrogen and organic matter. Nitrogen is removed by nitrifying and denitrifying bacteria, while aerobic bacteria are responsible for the decomposition of the organic matter. Microbial processes require oxygen and can result in depleted oxygen levels if the bioretention area is not adequately 2 of 8 California Stormwater BMP Handbook New Development and Redevelopment www .cabmphandbooks.com January 2003 - Bioretention TC-32 aerated. Sedimentation occurs in the S\Vale or ponding area as the velocity slows and solids fall out of suspension. TI1e removal effectiveness of bioretention has been studied during field and laboratory studies conducted by the University of Maryland (Davis et al, 1998). During these experiments, synthetic stormwater runoff ,vas pumped through several laboratory and field bioretention areas to simulate typical stonn events in Prince George's County, MD. Removal rates for heavy metals and nutrients are shown in Table 1. Table 1 Laborato1-y and Estimated Bioretention Davis et al. (1998); PGDER (1993) Pollutant Removal Rate Total Phosphorus 70-83% Metals (Cu, Zn, Pb) 93-98% TKN 68-80% Total Suspended Solids 90% Organics 90% Bacteria 90% Results for both the laboratory and field experiments were similar for each of the pollutants analyzed. Doubling or halving the influent pollutant levels had little effect on the effluent pollutants concentrations (Davis et al, 1998). TI1e microbial activity and plant uptake occurring in the bioretention area will likely result in higher removal rates than those determined for infiltration BMPs. Siting Criteria Bioretention BMPs are generally used to treat stormwater from impervious surfaces at commercial, residential, and industrial areas (EPA, 1999). Implementation ofbioretention for stonnwater management is ideal for median strips, parking lot islands, and swales. Moreover, the runoff in these areas can be designed to either divert directly into the bioretention area or convey into the bioretention area by a curb and gutter collection system. The best location for bioretention areas is upland from inlets that receive sheet flow from graded areas and at areas that will be excavated (EPA, 1999). In order to maximize treatment effectiveness, the site must be graded in such a way that minimizes erosive conditions as sheet flow is conveyed to the treatment area. Locations where a bioretention area can be readily incorporated into the site plan without further environmental damage are preferred. Furthermore, to effectively minimize sediment loading in the treatment area, bioretention only should be used in stabilized drainage areas. January 2003 California stormwater BMP Handbook New Development and Redevelopment www .cabmphandbooks.com 3 of 8 -- TC-32 Bioretention Additional Design Guidelines TI1e layout of the bioretention area is detemrined after site constraints such as location of utilities, underlying soils, existing vegetation, and drainage are considered (EPA, 1999). Sites with loamy sand soils are especially appropriate for bioretention because the excavated soil can be backfilled and used as the planting soil, thus eliminating the cost of importing planting soil. The use of bioretention may not be feasible given an unstable surrounding soil stratum, soils with clay content greater than 25 percent, a site with slopes greater than 20 percent, and/or a site with mature trees that would be removed during construction of the BMP. Bioretention can be designed to be off-line or on-line of the existing drainage system (EPA, 1999). The drainage area for a bioretention area should be between 0.1 and 0-4 hectares (0.25 and 1.0 acres). Larger drainage areas may require multiple bioretention areas. Furthermore, the maximum drainage area for a bioretention area is determined by the expected rainfall intensity and runoff rate. Stabilized areas may erode when velocities are greater than 5 feet per second (1.5 meter per second). TI1e designer should detem1ine the potential for erosive conditions at the site. The size of the bioretention area, which is a function of the drainage area and the runoff generated from the area is sized to capture the water quality volume. The recommended minimwn dimensions of the bioretention area are 15 feet (4.6 meters) wide by 40 feet (12.2 meters) long, where the minimum width allows enough space for a dense, randomly-distributed area of trees and shrubs to become established. Tims replicating a natural forest and creating a microclimate, thereby enabling the bioretention area to tolerate the effects of heat stress, acid rain, runoff pollutants, and insect and disease infestations which landscaped areas in urban settings typically are unable to tolerate. The preferred width is 25 feet (7.6 meters), with a length of twice the width. Essentially, any facilities wider than 20 feet {6.1 meters) should be twice as long as they are wide, which promotes the distribution of flow and decreases the chances of concentrated flow. In order to provide adequate storage and prevent water from standing for excessive periods of time the ponding depth of the bioretention area should not exceed 6 inches (15 centimeters). -Water should not be left to stand for more than 72 hours. A restriction on the type of plants that can be used may be necessary due to some plants' water intolerance. Furthermore, if water is left standing for longer than 72 hours mosquitoes and other insects may start to breed. ... ... - The appropriate planting soil should be backfilled into the excavated bioretention area. Planting soils should be sandy loam, loamy sand, or loam texture with a clay content ranging from 10 to 25percent . Generally the soil should have infiltration rates greater than 0.5 inches {1.25 centimeters) per hour, which is typical of sandy loams, loamy sands, or loams. The pH of the soil should range between 5.5 and 6.5, where pollutants such as organic nitrogen and phosphorus can be adsorbed by the soil and microbial activity can flourish. Additional requirements for the planting soil include a 1.5 to 3 percent organic content and a maximum 500 ppm concentration of soluble salts. 4 of 8 California Stonnwater BMP Handbook New Development and Redevelopment www.cabmphandbooks.com January 2003 ... .... Bioretention TC-32 Soil tests should be perlonned for every 500 cubic yards (382 cubic meters) of planting soil, with the exception of pH and organic content tests, which are required only once per bioretention area (EPA, 1999). Planting soil should be 4 inches (10.1 centimeters) deeper than the bottom of the largest root ball and 4 feet (1.2 meters) altogether. This depth will provide adequate soil for the plants' root systems to become established, prevent plant damage due to severe wind, and provide adequate moisture capacity. Most sites will require excavation in order to obtain the recommended depth. Planting soil depths of greater than 4 feet (1.2 meters) may require additional construction practices such as shoring measures (EPA, 1999). Planting soil should be placed in 18 inches or greater lifts and lightly compacted until the desired depth is reached. Since high canopy trees may be destroyed during maintenance the bioretention area should be vegetated to resemble a terrestrial forest community ecosystem that is dominated by understory trees. Three species each of both trees and shrubs are recommended to be planted at a rate of 2500 trees and shrubs per hectare (1000 per acre). For instance, a 15 foot (4.6 meter) by 40 foot (12.2 meter) bioretention area (600 square feet or 55.75 square meters) would require 14 trees and shrubs. TI1e shrub-to-tree ratio should be 2:1 to 3:1. Trees and shrubs should be planted when conditions are favorable. Vegetation should be watered at the end of each day for fourteen days following its planting. Plant species tolerant of pollutant loads and varying wet and dry conditions should be used in the bioretention area. The designer should assess aesthetics, site layout, and maintenance requirements when selecting plant species. Adjacent non·native invasive species should be identified and the designer should take measures, such as providing a soil breach to eliminate the threat of these species invading the bioretention area. Regional landscaping manuals should be consulted to ensure that the planting of the bioretention area meets the landscaping requirements established by the local authorities. The designers should evaluate the best placement of vegetation within the bioretention area. Plants should be placed at irregular intervals to replicate a natural forest. Trees should be placed on the perimeter of the area to provide shade and shelter from the wind. Trees and shrubs can be sheltered from damaging flows if they are placed away from the path of the incoming runoff. In cold climates, species that are more tolerant to cold winds, such as evergreens, should be placed in windier areas of the site. Following placement of the trees and shrubs, the ground cover and/or mulch should be established. Ground cover such as grasses or legumes can be planted at the beginning of the growing season. Mulch should be placed immediately after trees and shrubs are planted. Two to 3 inches (5 to 7.6 cm) of commercially-available fine shredded hardwood mulch or shredded hardwood chips should be applied to the bioretention area to protect from erosion. Maintenance TI1e primary maintenance requirement for bioretention areas is that of inspection and repair or replacement of the treatment area's components. Generally, this involves nothing more than the routine periodic maintenance that is required of any landscaped area. Plants that are appropriate for the site, climatic, and watering conditions should be selected for use in the bioretention cell. Appropriately selected plants will aide in reducing fertilizer, pesticide, water, and overall maintenance requirements. Bioretention system components should blend over time through plant and root growth, organic decomposition, and the development of a natural January 2003 California Stonnwater BMP Handbook New Development and Redevelopment www.cabmphandbooks.com 5 of 8 .... - TC-32 Bioretention soil horizon. TI1ese biologic and physical processes over time will lengthen the facility's life span and reduce the need for extensive maintenance. Routine maintenance should include a biannual health evaluation of the trees and shrubs and subsequent removal of any dead or diseased vegetation (EPA, 1999). Diseased vegetation should be treated as needed using preventative and low-toxic measures to the extent possible. BMPs have the potential to create very attractive habitats for mosquitoes and other vectors because of highly organic, often heavily vegetated areas mixed with shallow water. Routine inspections for areas of standing water within the BMP and corrective measures to restore proper infiltration rates are necessary to prevent creating mosquito and other vector habitat. In addition) bioretention BMPs are susceptible to invasion by aggressive plant species such as cattails, which increase the chances of water standing and subsequent vector production if not routinely maintained. In order to maintain the treatment area's appearance it may be necessary to prune and weed. Furthermore, mulch replacement is suggested when erosion is evident or when the site begins to look unattractive. Specifically, the entire area may require mulch replacement every two to three years, although spot mulching may be sufficient when there are random void areas. Mulch replacement should be done prior to the start of the wet season. New Jersey's Department of Environmental Protection states in their bioretention systems standards that accumulated sediment and debris removal ( especially at the inflow point) will normally be the primacy maintenance function. Other potential tasks include replacement of dead vegetation, soil pH regulation, erosion repair at in.flow points, mulch replenishment, unclogging the underdrain, and repairing overflow structures. There is also the possibility that the cation exchange capacity of the soils in the cell will be significantly reduced over time. Depending on pollutant loads, soils may need to be replaced within 5-10 years of construction (UD, 2000). Cost Construction Cost Construction cost estimates for a bioretention area are slightly greater than those for the required landscaping for a new development (EPA, 1999). A general rule of thumb (Coffman, 1999) is that residential bioretention areas average about $3 to $4 per square foot, depending on soil conditions and the density and types of plants used. Commercial, industrial and institutional site costs can range between $10 to $40 per square foot, based on the need for control structures, curbing, storm drains and underdrains. Retrofitting a site typically costs more, averaging $6,500 per bioretention area. The higher costs are attributed to the demolition of existing concrete, asphalt, and existing structures and the replacement of fill material with planting soil. The costs of retrofitting a commercial site in Matyland, Kettering Development, with 15 bioretention areas were estimated at $111,600. In any bioretention area design, the cost of plants varies substantially and can account for a significant portion of the expenditures. While these cost estimates are slightly greater than those of typical landscaping treatment ( due to the increased number of plantings, additional soil excavation, backfill material, use of underdrains etc.), those landscaping expenses that would be required regardless of the bioretention installation should be subtracted when determining the net cost. 6 of 8 California Stormwater BMP Handbook New Development and Redevelopment www .cabmphandbooks.com January 2003 ·- ... .wi - - - Bioretention TC-32 Perhaps of most importance, however, the cost savings compared to the use of traditional structural stonnwater conveyance systems makes bioretention areas quite attractive financially. For example, the use of bioretention can decrease the cost required for constructing stonuwater conveyance systems at a site. A medical office building in Maryland was able to reduce the amount of storm drain pipe that was needed from 800 to 230 feet -a cost savings of $24,000 (PGDER, 1993). And a new residential development spent a total of approximately $100,000 using bioretention cells on each lot instead of nearly $4001000 for the traditional stormwater ponds that were originally planned (Rappahanock, ). Also, in residential areas, stonnwater management controls become a part of each property owner's landscape, reducing the public burden to maintain large centralized facilities. Maintenance Cost The operation and maintenance costs for a bioretention facility will be comparable to those of typical landscaping required for a site. Costs beyond the normal landscaping fees will include the cost for testing the soils and may include costs for a sand bed and planting soil. References and Sources of Additional Information Coffman, L.S., R Goo and R Frederick, 1999: Low impact development: an innovative alternative approach to stonnwater management. Proceedings of the 26th Annual Water Resources Planning and Management Conference ASCE, June~' Tempe, Arizona. Davis,AP., Shokouhian, M., Sharma, H. andMinami, C., "Laboratory Study of Biological Retention (Bioretention) for Urban Stom1water Management," Water Environ. Res., 73(1), 5-14 (2001). Davis, AP., Shokouhian, M., Sharma, H., Minami, C., and Winogradoff, D. 'Water Quality Improvement through Bioretention: Lead, Copper, and Zinc," Water Environ. Res., accepted for publication, August 2002. Kim, H., Seagren, E.A., and Davis, A.P ., "Engineered Bioretention for Removal of Nitrate from Stonnwater Runoff," WEFI'EC 2000 Conference. Proceedings on CD ROM Research Symposium, Nitrogen Removal, Session 19, Anaheim CA, October 2000. Hsieh, C.-h. and Davis, AP. "Engineering Bioretention for Treatment of Urban Stormwater Runoff," Watersheds 2002, Proceedings on CDROM Research Symposium, Session 15, Ft. Lauderdale,FL,Feb.2002. Prince George's C.Ounty Department of Environmental Resources (PGDER), 1993. Design Manual for Use of Bioretention in Stormwater Management. Division of Environmental Management, Watershed Protection Branch. Landover, MD. U.S. EPA Office of Water, 1999. Stonnwater Technology Fact Sheet: Bioretention. EPA 832-F- 99-012. Weinstein, N. Davis, A.P. and Veeramachaneni, R. "Low Impact Development (UD) Stormwater Management Approach for the Control of Diffuse Pollution from Urban Roadways," 5th International Conference DiffusefNonpoint Pollution and Watershed Management Proceedings, C.S. Melching and Emre Alp, Eds. 2001 International Water Association January 2003 California Stormwater BMP Handbook New Development and Redevelopment www.cabmphandbooks.com 7 of8 TC-32 RKINGl.."OrSAEETFC~ 6"PONDING _ -Schematic of a Bioretention Facility (MDE, 2000) 8 of 8 California Stonnwater BMP Handbook New Development and Redevelopment www .cabmphandbooks.com Bioretention GRASS FILTER STRIP GAAVEL CURTAIN DAAIN OVERFLOW PLAN VIEW January 2003 3" OUTFALL PIPE CONNECT TO STREET 12'' GRAVEL (3/8" TO 5/8") OR OTHER APPROVED MA TERI AL VARIES DOWNSPOUT CLEANOUT WITH WATERTIGHT CAP ABOVE POND ING DEPTH _rESERVOIR 6"MIN. 18" SOIL/GROWING MEDIUM FILTER FABRIC DETAIL ONSITE FLOW THROUGH PLANTER NOT TO SCALE DOWNSPOUT BUILDING STRUCTURAL WALLS WITH WATERPROOF MEMBRANE 18" SOIL/GROWING MEDIUM FILTER FABRIC 4' ROW 7.7' CLEANOUT WITH WATERTIGH T CAP ABOVE PONDING DEPTH I PLANTINGS 2'' ABOVE SOIL ~ RESERVOIR-2" MIN. SMOOTH CONCRETE SEAT CAP 10" GR~VEL (3/8" TO 5/8") OR OTHER-.l!!.!!dl_4----+--liffi~~~~ 2% APPROVED MATERIAL PERFORATED PIPE TO RUN LENGHT OF PLANTER 100.00 •. FOUNDATION -------- DRAINS AS . .. REQUIRED DETAIL STREET FLOW THROUGH PLANTER NO T TO SCALE 10050 - - ATTACHMENTC BMP NUMERIC SIZING DMA DISTRIBUTION OAK AVE ; STATE ST -----------------, -_____ !_____ .. ---- ------T------ OMA 3: 900 SF@4%=36 SF I LID 3: 39 SF i OMA 1: 1500 SF@4%=60 SF ; LID 1: 300 SF -···----------·-···-·-· l .... ------· ---.. 1 -· · · ··--------· -· ··--------... j -··---------·--··-.. OMA 4: 3625 SF@ 4%=145 SF i LID 4: 200 SF OMA 2: 1330 SF @4%= 53 SF LID 2: 80 SF ··--·--·-··--··---· .. ·-----·--·--- I ... ·-·----··--.. .. ------· -·-···· DMA5: 1100 SF@4%= 44 SF ; LID 5: 99 SF : DMA6: 1500 SF @4%"' 60 SF ,LID 6: 60 SF .. --------·--··----+·· -··---.... L .. ··--·. -·-·· ·-· ···-··---·· - -.. -···--1------·--·-· ;LID 7: 48 SF I ----------- iLID 8: 184 SF : OMA 7: 1100 SF@4%=44 SF I -··-···--·--·-········-·· ! OMA 8: 2000 SF @4%= 80 SF ··-·--. ··--·-···-·-·-·--·-· OMA 9: 1650 SF @4%"' 66 SF LID 9: 87 SF TOTAL: 5625 SF , TOT AL: 9080 SF ..... ATTACHMENTD CITY SUSMP FORMS City of Carlsbad STORM WATER STANDARDS QUESTIONNAIRE E-34 Development Services Land Development Engineering 1635 Faraday Aven ue 760-602-2750 www.carlsbadca.gov I INSTRUCTto~S: To address post-development pollutants that may be generated from development projects, lhe City requires thal new development and significant redevelopment priority projects incorporate Permanent Storm Waler Best Management Practices (BMP's) into the project design per the City's Standard Urban Stormwater Management Plan (SUSMP). To view the SUSMP, refer to the Engineering Standards (Volume 4, Chapter 2). Initially this questionnaire must be completed by the applicant in advance of submitting for a development application (subdivision, discretionary permits and/or construction permits). The results of the questionnaire determine the level of storm water standards that must be applied to a proposed development or redevelopment project Depending on the outcome, your project will either be subject to 'Standard Slorrnwater Requirements' or be subject to additional criteria called 'Priority Development Project Requirements'. Many aspects of project site design are dependent upon the storm water standards applied to a project. Your responses to the questionnaire represent an initial assessment of the proposed project conditions and impacts. City staff has responsibility for making the final assessment after submission of the development application. If staff determines that the questionnaire was incorrectly filled out and is subject to more stringent storm water standards than initially assessed by you, this will result in the return of the development application as incomplete. In this case, please make the changes to the questionnaire and resubmit to the City. If you are unsure about the meaning of a question or need help in determining how to respond to one or more of the questions, please seek assistance from Land Development Engineering staff. A separate completed and signed questionnaire must be submitted for each new development application submission. Only one completed and signed questionnaire is required when multiple development applications for the same project are submitted concurrently. In addition to this questionnaire, you must also complete, sign and submit a Project Threat Assessment Form with construction permits for the project. Please start by completing Step 1 and follow the instructions. When completed, sign the form at the end and submit this with your application to the city. STEP1 .TO BE COMPLETED FOR ALL PROJECT To determine if your project is a priority development project, please answer the following questions: 1. Is your project LIMITED TO constructing new or retrofitting paved sidewalks. bicycle lanes or trails that meet the following criteria: (1) Designed and constructed to direct storm water runoff to adjacent vegetated areas, or other non-erodible permeable areas; OR (2) designed and constructed to be hydraulically disconnected from paved streets or roads; OR (3) designed and constructed with permeable pavements or surfaces in accordance with USEPA Green Streets uidance? 2. Is your project LIMITED TO retrofitting or redeveloping existing paved alleys, streets, or roads that are designed and constructed in accordance with the USEPA Green Streets guidance? YES NO If you answered "yes· to one or more of the above questions, then your project is NOT a priority development project and therefore is NOT subject to the storm water criteria required for priority development projects. Go to step 4, mark the last box stating "my project does not meet PDP requirements" and complete applicant Information. E-34 Page 1 of 3 Effective 6/27 /13 STORM WATER STANDARDS QUESTIONNAIRE E-34 STEP2 Development Services Land Development Engineering 1635 Faraday Avenue 760-602-2750 www.carlsbadca.gov TO BE COMPLETED FOR ALL NEW OR REDEVS.OPUENT PROJECTS To determine if your project is a priority development project, please answer the following questions: YES 1. Is your project a new development that creates 10,000 square feet or more of impervious surfaces collectively ~ over the entire project site? This includes commercial, industrial, residential, mixed-use, and public development oroiects on public or private land. 2. Is your project creating or replacing 5,000 square feet or more of impervious surface collectively over the entire / project site on an existing site of 10,000 square feet or more of impervious surface? This includes commercial, industrial. residential. mixed-use and oublic development projects on oublic or orivate land. 3. Is your project a new or redevelopment project that creates 5,000 square feet or more of impervious surface collectively over the entire project site and supports a restaurant? A restaurant is a facility that sells prepared foods and drinks for consumption. including stationary lunch counters and refreshment stands selling prepared foods and drinks for immediate consumption. 4. Is your project a new or redevelopment project that creates 5,000 square feet or more of impervious surface collectively over the entire project site and supports a hillside development project? A hillside development project includes development on any natural slope that is twenty-five percent or greater. 5. Is your project a new or redevelopment project that creates 5,000 square feet or more of impervious surface ~ collectively over the entire project site and supports a parking lot. A parking lot is a land area or facility for the temoorarv oarkina or storaae of motor vehicles used oersonallv for business or for commerce. 6. Is your project a new or redevelopment project that creates 5,000 square feet or more of impervious surface collectively over the entire project site and supports a street. road, highway freeway or driveway? A street, road, highway, freeway or driveway is any paved impervious surface used for the transportation of automobiles, trucks. motorcycles, and other vehicles. 7. Is your project a new or redevelopment project that creates or replaces 2,500 square feet or more of impervious surface collectively over the entire site, and discharges directly to an Environmentally Sensitive Area (ESA)? "Discharging Directly to · includes flow that is conveyed overland a distance of 200 feet or fess from the project to the ESA, or conveyed in a pipe or open channel any distance as an isolated flow from the oroject to the ESA (i.e. not comminafes with flows from adjacent lands).* 8. Is your project a new development that supports an automotive repair shop? An automotive repair shop is a facility that is categorized in any one of the following Standard Industrial Classification (SfC) codes: 5013, 5014 5541, 7532-7534 or 7536-7539. 9. Is your project a new development that supports a retail gasoline outlet (RGO)? This category includes RGO's that meet the following criteria: (a) 5,000 square feet or more or (b) a project Average Daily Traffic (ADT) of 100 or more vehicles Der dav. 10. Is your project a new or redevelopment project that results in the disturbance of one or more acres of land and are expected to generate pollutants post construction? 11. ls your project located within 200 feet of the Pacific Ocean and (1) creates 2,500 square feet or more of .y' impervious surface or (2) increases impervious surface on the property by more than 10%? NO / / / ./ " ./ / If you answered "yes" to one or more of the above questions, you ARE a priority development project and are therefore subject to implementing structural Best Management Practices (BMP's) in addition to implementing Standard Storm Water Requirements such as source control and low impact development BMP's. A Storm Water Management Plan (SWMP) must be submitted with your application(s) for development. Go to step 3 for redevelopment projects. For new projects, go to step 4 at the end of this questionnaire, check the "my project meets PDP requirements" box and complete applicant information. If you answered "no" to all of the above questions, you ARE NOT a priority development project and are therefore subject to implementing only Standard Storm Water Requirements such as source control and low impact development BMP's required for all development projects. A Storm Water Management Plan (SWMP) is not required with your application(s) for development. Go to step 4 at the end of this questionnaire, check the "my project does not meet PDP requirements" box and complete applicant Information. E-34 Page 2 of3 Effective 6/27 /13 STORM WATER STANDARDS QUESTIONNAIRE E-34 STEP3 Development Services Land Development Engineering 1635 Faraday Avenue 760-602-2750 www.carlsbadca.gov TO BE COMPLETED FOR REDEVELOPMENT PROJECTS A.'t ARE PRIORITY DEVELOPEMENT PROJECTS ONLY Com lete the uestions below re ardin our redevelo ment ro·ect: YES NO Does the redevelopment project result in the creation or replacement of impervious surface in an amount of less than .~ 50% of the surface area of the reviousl existi develo ment? "¥'" If you answered "yes: the structural BMP's required for Priority Development Projects apply only to the creation or replacement of impervious surface and not the entire development. Go to step 4, check the "my project meets PDP requirements" box and complete applicant Information. If you answered "no," the structural BM P's required for Priority Development Projects apply to the entire development. Go to step 4, check the "m ro·ect meets PDP re uirements" box and com lete a llcant Information • • ~ STEP4 CHECK THE APPROPRIATE BOX AND COMPLETE APPl:JCANT INFORMATION . ..• ""'· "., ·-····" "' I 'ir My project meets PRIORITY DEVELOPMENT PROJECT (PDP) requirements and must comply with additional stormwater criteria per the SUSMP and I understand I must prepare a Storm Water Management Plan for submittal at time of application. I understand flow control (hydromodification) requirements may apply to my project. Refer to SUSMP for details. 0 My project does not meet POP requirements and must only comply with STANDARD STORMWATER REQUIREMENTS per the SUSMP. As part of these requirements, I will incorporate low impact development strategies throughout my project. Applicant Information and Signature Box tSS~is~adrona Drive Sidney BC VSL 5P2 ~pplicant Name: Daniel Cox -State and Oak Carlsbad Properties Ltd. Applicant Title: President Applicant Signature: ~ Date· M arcri 25th/2015 This Box for City Use Only City Concurrence: I YES I NO I I By: Date: Project ID: * Environmentally Sensitive Areas include but are not limited to all Clean Water Act Section 303(d) impaired water bodies; areas designated as Areas of Special Biological Significance by the State Water Resources Control Board (Water Quality Control Plan for the San Diego Basin (1994) and amendments); water bodies designated with the RARE beneficial use by the State Water Resources Control Board (Water Quality Control Plan for the San Diego Basin (1994) and amendments); areas designated as preserves or their quivalent under the Multi Species Conservation Program within the Cities and County of San Diego; and any other equivalent environmentally sensitive areas which have been identified by the Copermittees. E-34 Page 3 of3 Effective 6/27113 • - ATTACHMENTE HMP EXEMPTION EXHIBIT - -tM.m --mA5III 90Ull)MY I•--• t NA'I\JftAL. n.GW ,-AlH i;@ ,,_'DOH""""" NEA HMP EXEMPTION EXHIBIT t NQf•8GOR:t:I I 1 1-w w c::: 1- (/) ~ K&S ENGINEERING, INC. ~ Planning . Engineering . Surveying 7801 Mission Center Court, Suite 100 Son Diego, CA 92108 (619) 296-5565 Fax: (619) 296-5554 I Ii I --------~~--------------.. -... ----· ,\ I I I NOTE: PROPOSED 10' RADIUS DEDICATION CHECK DAM SE-4 STABILIZED CONSTRUCTION ENTRANCE/EXIT TC-1 --<t- OAKAVENUE RUMBLE STRIPS OR MIN. 4" COARSE AGGREGATE/FILTER FABRIC STABILIZED CONSTRUCTION ENTRANCE WITH STEEL PLATES TC-1 N.T.S. PORTABLE SANITARY FACILITY WM-9 -1-+ + + + + + + + .;-+ + + + + + + + + + + + + + + + + + + -i-' + + + + + + + + + + + + + + + + + + + + J,- • • ·. j ~·11 COARSE AGGREGATE 12" MIN. FILTER FABRIC (2 KIGH) ,.--~-v--G=R""-;AVEL 13AGS SECTION A SE-10 N.T.S. I GRAVEL BAGS - ARE STACKED TIGHTLY CATCH BASIN / A STORM DRAIN INLET PROTECTION DETAIL SE-10 NOT TO SCALE . ·" I ' -~." . . I ... l I , .... I· I . ... __ ii l_ 0 5 10 SILT FENCE SE-1 LEGEND: DESCRIPTION CONSTRUCTION BMP'S CODE SYMBOL (CASQA) CHECK DAM/STORM DRAIN INLET PROTECTION SE-4, SE-10 ~ "\::i CURB INLET PROTECTION G::,dJ ,JI SILT FENCE SE-1 ---0--- STABIUZED CONSTRUCTION ENTRANCE TC-1 . i I i~ I I -. MATERIAL STORAGE WM-1,WM-2 klm'ffift~ WASTE COLLECTION CONCRETE WASHOUT PORTABLE SANITARY FACILITY DIRECTION OF FLOW PONDING HT. l 12" MIN l ALT. DETAIL STEEL OR WOOD POST 3$" HIGH MAX. S" MAX. STORAGE HT. -r 12" MIN WM-5 ~ WM-8 I ., + + : + : " ~ WM-9 I •I + + PONDING HT. FILTER FABRIC ,----ATTACKED SECURELY RUNOFF TO UPSTREAM SIDE OF POST. CONCRETE WASHOUT SE1 WM-8 TRENCH \l\'ITH GRAVEL TRENCH WITH NATIVE BACKFILL N.T.S. N.T.S. EXTRA STRENGTH FILTER FABRIC NEEDED WITHOUT WIRE MESK SUPPORT. WASTE COLLECTION WM-5 ATTACH FILTER FABRIC SECURELY TO UPSTREAM SIDE OF POST. NOTE 1.-THE CON'fRACTOR SHALL INSPECT AND REPAIR FENCE AFTER EACH STORM EVENT AND REMOVE SEDIMENT. MATERIAL STORAGE WM-1 WM-2 ' 10' ( 3m) MAXIMUM SPACING l!\IITH WIRE SUPPORT FENCE 2.-REMOVED SEDIMENT SHALL SE DEPOSITED TO AN AREA THAT WILL NOT CONTRIBUTE TO SEDIMENT OFF-SITE AND CAN SE PERMANEN11.Y STABILIZED. 3.-SILT FENCE SHALL BE PLACED ON SLOPE CONTOURS TO FACILITATE MAXIMUM PONDING EFFICENCY. NOTES: 5' (1.8m) MAXIMUM SPACING 1MTHOUT WIRE SUPPORT FENCE. SILTFENCE SE-1 NOT TO SCALE CONCRETE WASHOUT AREA 1. EXCESS AND WASTE CONCRETE SHALL NOT BE WASHED INTO THE STREET OR INTO A DRAINAGE SYSTEM. 2. FOR WASHOUT OF CONCRETE AND MORTAR PRODUCTS, A DESIGNATED CONTAINMENT FACILITY OF SUFFICIENT CAPACITY TO RETAIN LIQUID AND SOLID WASTE SHALL BE 3. PROVIDED ON SITE. SLURRY FROM CONCRETE AND ASPHALT SAW CUTTING SHALL BE VACUUMED OR CONTAINED, DRIED, PICKED UP AND DISPOSED OF PROPERLY. CONCRETE WASTE MANAGEMENT WM-8 BERM ED CONTAINMENT AREA NOT TO SCALE FIGURE 5-A I SH~ET I EE] CITY OF CARLSBAD ENGINEERING DEPARTMENT . SWMP FOR: STATE MIXED USED 30 20 30 CT 14-01 EROSION CONTROL APPROVED: JASON S. GELDERT GRAPHIC SCALE: 1" = 10' ENGINEERING MANAGER PE 53912 EXPIRES 9/30/2016 DATE IF PLAN SIZE IS LESS THAN IS A REDUCED COPY. SCALE ACCORDINGLY. 24"x36", THIS PLAN DWN BY: NO CHKD BY: RVWD BY: I PROJECT NO. I DRAWING NO. CT 14-01 478-1A z 0 in 0 °' w <( 12" GRAVEL (3/8" TO 5/8") OR OTHER APPROVED MA TERI AL VARIES FILTER FABRIC DETAIL ONSITE FLOW THROUGH PLANTER NOT TO SCALE DOWNSPOUT BUILDING STRUCTURAL WALLS lMTH WATERPROOF MEMBRANE i8" SOIL/GROWING MEDIUM FILTER FABRIC ROW 4' 7.7' DETAIL STREET FLOW THROUGH PLANTER NOT TO SCALE L 9 DMA1+2!Z!!!.Jt,;;;;-;;t-1~;;:;;:;:;::;;;:::;;;;;;:~;;-~-'i:~~~~'"""J"!"""":'""'r"".]"'"':'.""::-!"':J'-r'.:J""i::~r--~--1 ' .. ' . 1-w w 0::: 1- (J) w 1-j:: (J) DMA9 ~ - DMA6 ·1 I: I: I u· ~ II • " - ' ' ~ -------i~ OMA DISTRIBUTION ::: OAK AVE OMA 3: 900 SF @ 4%=36 SF LID3: 39SF DMA4: 3625SF@4%=145 SF LID4:200SF Cl STATE ST DMA 1: 1500 SF@4%=60SF LID 1: 300 SF OMA 2: 1330 SF@4%= 53 SF LID2: 80 SF OAK AVENUE DMA5: 1100 SF@4%=44 SF LIDS: 99SF OMA 6: 1500 SF@4%= 60 SF LID 6: 60 SF ROOF PLAN OMA 7: 1100 SF @4%= 44 SF 1 OMA 8: 2000 SF @4%= 80 SF ! DMA9: 1650 SF@4%=66SF TOTAL: 5625 SF i TOTAL: 9080 SF K& S ENGINEERING, INC. Planning . Engineering . Surveying 780' Miss:or. Center Co;,t, Suite 100 San Diego, CA 92108 (519) 296-5565 Fax (619) 296-5554 LID7:48 SF LID 8: 184 SF LID 9: 87 SF LEGEND DM A TO STA TE STREET OMA TO OAK A VENUE SYMBOL H=SB=Fl=a I ' ' :----, ' ' ' ' I ' ' i I ' ' ' I I i ; i i i l ! I ' >-w ....J ....J <( REQUIRED TREATMENT CONTROL BMP TABLE DESCRIPTION QUANTITY FLOW TI-lRU PLANTER (CLEANSING) 9 EA. .. I I ~ . I I ~ I I I ~ I I I I ~ 0 10 20 40 GRAPHIC SCALE: 1" BMP TABLE BMPID# BMPTYPE SYMBOL CASQA NO. QUANTITY DRAWING NO. SHEET NO.(S) INSPECTION FREQUENCY MAINTENANCE CONSTRUCTION FREQUENCY SIGN OFF TREATMENT CONTROL AND LOW INPACT DESIGN (LLD.) Ga@r ~® ® SOURCE CONTROL ® ® TRASH ENCLOSURE SITE DESIGN/ LANDSCAPE EFFICIENT IRRIGATION I I L ....... . . . . . . . .......... ........ . . . . . . . . . . D I DI ~ I I TC-32 SD-32 SD-10 SD-12 --..J""'\...--....r"l....--....r"l....--....r-i--~---! 50 20' SITE PLAN IF PLAN SIZE IS LESS THAN 24"x36", IS A REDUCED COPY. SCALE PLAN ACCORDINGLY. 5 2 1 ,-- [ '--~ THIS 1 1 1 AS NEEDED 2 TIMES A YEAR AS NEEDED AS NEEDED AS NEEDED AS NEEDED SWMP NO.:_N/_A __ _ MAINTENANCE AGREEMENT DOCUMENT: YES NO RECORDATION NO.: ____ _ PARTY RESPONSIBLE FOR MAINTENANCE: NAME: STATE & OAK CARLSBAD PROPERTIES LTD. CONTACT:· DANIEL COX ADDRESS:10946 MADRONA DRIVE SIDNEY BC V8L 5P2 CANADA PHONE N0.:250.516.0445 PLAN PREPARED BY: NAME HOSSEIN ZOMORRODI COMPANY K&S ENGINEERING ADDRESS 7801 MISSION CENTER CT. SUITE 100 SAN DIEGO, CA 92108 PHONE NO. 1619) 296-5565 CERTIFICATION _;4::,:32""3,,_5 __ _ BMPNOTES: 1. THESE BMPS ARE MANDATORY TO BE INSTALLED PER MANUFACTURER'S RECOMMENDATIONS OR THESE PLANS. 2. NO CHANGES TO THE PROPOSED BMPS ON THIS SHEET WITHOUT PRIOR APPROVAL FROM THE CITY ENGINEER. 3. NO SUBSTITUTIONS TO THE MATERJAL OR TYPES OR PLANTING TYPES WITHOUT PRIOR APPROVAL FROM THE CITY ENGINEER. 4. NO OCCUPANCY WILL BE GRANTED UNTIL THE CITY INSPECTION STAFF HAS INSPECTED THIS PROJECT FOR APPROPRIATE BMP CONSTRUCTION AND INSTALLATION. FIGURE 5-B I SH~ET I CITY OF CARLSBAD I SHE~TS I ENGINEERING DEPARTMENT SWMP FOR STATE MIXED USED 30 CT 14-01 DMA AREAS AND POST CONSTRUCTION BMP'S APPROVED: JASON S. GELDERT ENGINEERING MANAGER PE 53912 EXPIRES 9/30/2015 DATE DWN BY: • A I PROJECT NO. I DRAWING NO. CHKD BY: CT 14-01 RVWD BY: 478-1A --------------------------------------·-·-·--······--.,,. __ , -----·-·------------------ a. z 0 u 0 -0 -u, co "' 0 ,;, ;;- "' ~ 0 w " 0 O'. ? • I D -D > 'Ji