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Home My WebLink AboutMS 05-19; HEMLOCK PROJECT; STORMWATER MANAGEMENT PLAN; 2005-10-21STORM WATER MANAGEMENT PLAN (SWMP) for HEMLOCK PROJECT MS 05-I9ISDP 05-09ICP 05-IOICDP 05-25 APN: 204-251-06 Prepared for.- City of Carlsbad 1635 Faraday Avenue Carlsbad, CA 92008 Telephone: (760) 602-4600 PreDared by: Alta Consultants 4901 Morena Blvd., Suite 409 San Diego, CA 92117 (858) 581-6101, Fax (858) 581-6138 Bartolome J. Pastor, RCE 38606 Project Site Address.- Hemlock Avenue Carlsbad, CA 92008 Revision Date.- October 21, 2005 Submitted by: GOFAT, LLC 160 Tamarack Ave. Carlsbad, CA 92008 ( RC' NO- 3860 Ep 3/3/ r Date ALTA CONSULTANTS PLANNING *ENGINEERING *SURVEYING 4901 Morena Blvd. Suite 409 San Diego, CA 92117 TEL.(858) 581-6101 FAX (858) 581-6138 E-Mail: ALTACONSULTANTS®AOL.COM Storm Water Management Plan (SWMP) Hemlock Project, MS 05-19/SDP 05-09ICP 05-10/CDP 05-25 APN: 204-251-06 Table of Contents INTRODUCTION PROJECT DESCRIPTION 1.1. Topogrophy and Land Use......................................................................................................... 1.2. Hydrologic Unit Contribution..................................................................................................... WATER QUALITY ENVIRONMENT 2.1. Beneficial Uses........................................................................................................................... 2.1.1. Inland Surface Waters.................................................................................................... 2.1.2. Coastal Waters............................................................................................................... 2.1.3. Groundwater.................................................................................................................. 2.2. 303(d) Status............................................................................................................................... CHARACTERIZATION OF PROJECT RUNOFF 3.1. Existing and Post-Construction Drainage................................................................................... 3.2. Post-Construction Expected Discharges..................................................................................... WATER QUALITY ENVIRONMENT. 4.1. Pollutants of Concern................................................................................................................. 4.2. Construction BMPs...................................................................................................................... 4.3. Post-Construction BMPs............................................................................................................ 4.2.1. Site Design BMPs.......................................................................................................... 4.2.2. Source Control BMPs.................................................................................................... 4.2.3. Treatment Control BMPs............................................................................................... OPERATION AND MAINTENANCE PROGRAM FISCAL RESOURCES SUMMARY & CONCLUSIONS ATTACHMENTS AttachmentA.........................................................................................................Vicinity Map AttachmentB.....................................................................................................Hydrology Map Attachment C..........................................................................................Tentative Map Exhibit Attachment D..............................................................................Hydrology Calculation Tables Attachment E ..........................................................................85th Percentile Precipitation Map AttachmentF........................................................................................................Formula Sheet Attachment G ............................................................ Catch Basin w/Fossil Filter Insert Details Attachment H...............................................Sample Water Pollution Fact Sheets (County SD) Storm Water Management Plan (SWMP) Hemlock Project, MS 05-19/SDP 05-09/CP 05-10/COP 05-25 APN: 204-251-06 INTRODUCTION: The Storm Water Management Plan (SWMP) is required per the City of Carlsbad Standard Urban Storm Water Mitigation Plan (SUSMP) and is a requirement under the California Regional Water Quality Control Boara San Diego Region Order No. 2001-01 and is categorized as a Medium Priority project. The purpose of this SWMP is to address the water quality impacts from the proposed improvments on the Hemlock Project (MS 05-19/SDP 05-09/CP 05-10/CDP 05-25). Best Management Practices (BMPs) will be utilized to provide a long-term solution to water quality. This SWMP is also intended to ensure the effectiveness of the BMPs through proper maintenance. The SWMP is subject to revisions as needed by the Engineer. 1.0 PROJECT DESCRIPTION The 0.13 acre Hemlock Project is located on the north side of Hemlock Avenue, just east of the intersection of Hemlock Avenue and Carlsbad Boulevard in the City of Carlsbad (see Attachment A for Vicinity Map). This project will consist of the demolition of an existing multi-family building and the construction of 2 attached single-family units with underground parking. 1.1 Topography and Land Use The existing project area is designated urban and is currently developed. The Pacific Ocean is approximately 300 ft due west. This SWMP is confined within the limits of the development. Runoff from the property located easterly currently flows along the concrete driveway into a 2" storm drain pipe and outlets into Hemlock Ave. This drainage flow will not be altered. The properties located northerly and northwesterly are at a lower grade than the proposed project and runoff flows will not be affected. 1.2 Hydrologic Unit Contribution The Hemlock Project is located in the Carlsbad Hydrologic Unit in the Buena Vista Creek Watershed and in the El Salto Hydrologic Sub Area (HSA) (4.21). The project shall follow the natural drainage pattern westerly along Hemlock Avenue to Carlsbad Boulevard. The on-site storm drain system for this project will consist of multiple catch basins, cleanouts, storm drain pipes, basement sump pump and sidewalk underdrain to mitigate runoff to the existing system in Hemlock Avenue. Runoff will then be conveyed through existing curb & gutter to the existing storm drain inlet at Carlsbad Boulevard. The runoff quantity and velocities leaving the site are shown in the hydrology calculation tables in Attachment D. Overall, the project area represents less than 0.1 percent of the watershed. 2.0 WATER QUALITY ENVIRONMENT 2.1 Beneficial Uses The beneficial use for the hydroloic unit are included in this section. These definitions have been extracted from the Water Quality Control Plan for the San Diego Basin. Storm Water Management Plan (SWMP) Hemlock Project, MS 05-19/SDP 05-09ICP 05-IOICDP 05-25 APN: 204-251-06 MUN - Municipal and Domestic Supply: Includes uses of water for community, military, or individual water supply systems including, but not limited to, drinking water supplyu. AGR - Agricultural Supply: Includes uses of water for individual activites that do not depend primarily on water wuality including, but not limited to, mining, cooling water supply, hydraulic conveyance, gravel washing, fire protection, or oil well re-pressurization. 1ND - Industrial Service Supply: Includes uses of water for industrial activities that do not depend primarily on water quality including, but not limited to, mining, cooling water supply, hydraulic conveyance, gravel washing, fire protection, or oil well re-pressurization. REd - Contact Recreation: Includes uses of water for recreational activities involving body contact with water, where ingestion of water is reasonably possible. These uses include, but are not limited to, swimming, wading, water-skiing, skin and SCUBA diving, surfing, white water activities, fishing, or use of natural hot springs. REC2 - Non-Contact Recreation: Includes the uses of water for recreational involving proximity to water, but not normally involving body contact with water, where ingestion of water is reasonably possible. These uses include, but ar enot limited to, picnicking, sunbathing, hiking, camping, boating, tide pool and marine life study, hunting, sightseeing, or easthetic enjoyment in conjunction with the above activities. WARM - Warm Freshwater Habitat: Includes uses of water that support warm water ecosystems including, but not limited to, preservation or enhancement of aquatic habitats, vegitation, fish or wildlife, including invertebrates. MAR - Marine Habitat: Includes uses of water that support marine ecosystems including, but not limited to, preservation or enhancement of marine habitats, vegetation such as kelp, fish, shellfish, or wildlife (e.g., marine mammals, shorebirds). WILD - Wildlife Habitat: Inculdes uses of water that support terrestrial ecosystems including, but not limited to, preservation and enhancement of terrestrial habitats, vegetation, wildlide, (e.g., mammals, birds, reptiles, amphibians, invertebrates), or wildlife water and food sources. BIOL - Preservation of Biological Habitats of Special Significance: Includes uses of water that support designated areas or habitats, such as established refuges, parks, sanctuaries, ecological reserves, or Areas of Special Biological Significance (ASBS), where the preservation or enhancement of natural resources requires special protection. RARE - Rare, Threatened, or Endangered Species: Includes uses of water that support habitats necessary, at least in part, for the survival and successful maintance of plant or animal species established under state or federal law as rare, threatened or endangered. 2.1.1 Inland Surface Waters Inland surface waters for the El Salto HSA (4.21) have the following beneficial uses: AGR IND. REC1 REC2 WARM WILD RARE Storm Water Management Plan (SWMP) Hemlock Project, MS 05-19/SDP 05-09ICP 05-10/CDP 05-25 APN: 204-251-06 2.1.2 Coastal Waters Coastal waters for the El Salto HSA (4.21) have the following beneficial uses: REC1 REC2 BIOL EST (potential) WILD RARE MAR WARM 2.1.3 Groundwater (3roundwaters for the El Salto HSA (4.21) have the following beneficial uses: MUN AGR IND (potential) 2.2 303(d) Status According to the California 303(d) list published by the San Diego Regional Water Quality Control Board, there are no impaired waterbodies that are associated with this project. The project location and.watersheds have been compared to the current published 303(d) list of impaired waterbodies and the nearest impaired waterbody is Buena Vista Lagoon, impaired by sedimentation/siltation. Buena Vista Lagoon is approximately 1 mile north of this project location. 3.0 CHARACTERIZATION OF PROJECT RUNOFF 3.1 Existing and Post-Construction Drainage The proposed project will not alter drainage patterns on the site, nor will there be an increase in the amount of impervious area on the site. Cleanouts, catch basins and drains, as shown in Attachment B, are proposed to collect the runoff created by this development. The existing and proposed land uses are virtually identical, therefor the composite runoff coefficient will remain the same (C=0.85). The peak flow rate leaving the site will only marginally increase from Q0.68 cfs under the existing condition (sheet flow) to Q=0.79 cfs under the proposed condition. Post-construction runoff will be directed into Hemlock Avenue and will flow SW along curb & gutter to the existing storm drain system in Carlsbad Blvd. This system will not divert water from its natural flow direction. The preliminary design of this system is included in the Hydrology map in Attachment B. Summaries of the post-construction calculations are included in Attachment D. The flows were developed using the 85th Percentile Precipitation map developed by the County of San Diego, as well as the County of San Diego Hydrology Manual. Storm Water Management Plan (SWMP) Hemlock Project, MS 05-19/SDP 05-09ICP 05-I0ICDP 05-25 APN: 204-251-06 3.2 Post-Construction Expected Discharges 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 following constituants are commonly found on similar properties and could affect water quality: Sediment discharge due to construction activities Nutrients from fertilizers Trash and debris Hydrocarbons from paved areas Pesticides from landscaping and home use 4.0 MITIGATION MEASURES TO PROTECT WATER QUALITY 4.1 Pollutants of Concern The proposed project has minimal change in grades or flow directions that could change the quality of storm water. The primary materials and wastes that have the potential to pollute storm water during construction include: Sediments and other surface material Concrete mix waste during construction Trash and debris Non-metal products such as fuels, adhesive paint, etc. Paving operations Wood, concrete and other building materials This project is not expected to generate significant amounts of non-visible pollutants after construction. However, the following constituants are commonly found on similar properties and could affect water quality: Sediments & nutrients Trash and debris Oil & grease Oxygen demanding substances Bacteria & viruses Pesticides To address water quality for the project, BMPs will be implemented during construction and post- construction. Storm Water Management Plan (SWMP) Hemlock Project, MS 05-19/SDP 05-09/CP 05-10/CDP 05-25 - - APN: 204-251-06 4.2 Construction BMPs Grading and Improvement plans for this project are not yet available, however, potential BMPs may include: Stabilized Construction Entrance Silt Fence Gravel Bag Barriers Storm Drain Inlet Protection Selected construction BMPs for this project will be constructed and maintained so as to comply with all applicable ordinances and guidance documents. 4.3 Post-Construction BMPs Pullutants of concern as noted in section 3.0 will be addressed through three types of BMPs. These types of BMPs are site design, source control, and treatment control. 4.3.1 Site Design BMPs Grassy areas (at the rear portion of the lot) and landscaping will be installed on-site to promote absorption and enhance asthetics. The existing site is entirely concrete, with the exception of the building footprint. The proposed project will add is areas to the site (approx. 10% of the total site area). Landscaping of common areas are incorporated into the design (most landscaping of common areas will use permanent planter boxes or similar). The landscaping will consist of both native and non-native plants. The irrigation system for these landscaped areas and planters will be monitored to prevent over-irrigation. 4.3.2 Source Control BMPs Source control BMPs will consist of measures to prevent polluted runoff. This program will include an educational component directed at the homeowner. The homeowner will receive a set of brochures developed by the County's Environmental Health Department see Attachment H. These will include the following: Stormwater Runoff Pullution Fact Sheet Stormwater Runoff Pullution Prevention Tips for Homeowners Stormwater Pollution Prevention Yard Work (Landscaping, Gardening, Pest Control) Stormwater Pollution Prevention Pet Waste 4.3.3 Treatment Control BMPs The following treatment control BMPs will be implemented to address water quality: Fossil Filter Insert on Catch Basins Bio-filter/grassy areas Placements of the BMPs are noted in Attachment C. Storm Water Management Plan (SWMP) Hemlock Project; MS 05-19/SDP 05-09ICP 05-IOICDP 05-25 APN: 204-251.06 5.0 OPERATION AND MAINTENANCE PROGRAM The operation and maintenace requirements for each type of BMP is as follows: 5.1 Catch Basins wlFossil Filter Insert The operational and maintenance needs of the Catch Basins w/Fossil Filter Insert are: Preventative maintenance on monitoring by visual inspection. See Attachment F for additional manufacturer's recommendations Inspection Frequency The facility will be inspected: Once a month at a minimum After every large storm (after every storm monitored or those storms with more than 0.50 inches of precipitation) On a weekly basis during extended periods of wet weather Debris and Sediment Disposal Waste generated at catch basins and drains is ultimately the responsibility of the homeowner. This project proposes a Home Owners Association (HOA) to determine responsibility of Storm Water Maintenance on-site. Disposal of sediment, debris, and trash will comply with applicable local, county, state, and federal waste control programs. Hazardous Waste Suspected hazardous wastes on-site or discharged by the project will be analyzed to determine disposal options. Contractor shall employ or designate on-site Hazardous Waste Monitoring while site is under construction. Hazardous wastes generated onsite will be handled and disposed of according to applicable local, state, and federal regulations. A solid or liquid waste is considered a hazardous waste if it exceeds the criteria listed in the CCR, Title 22, Article 11. Maintenance Costs After installation, the catch basins and Fossil Filter inserts will be maintained by the homeowners with an anticipated yearly cost of $500 per filter. Storm Water Management Plan (SWMP) Hemlock Project, MS 05-19/SDP 05-09ICP 05-I0iCDP 05-25 APN: 204-25146 6.0 FISCAL RESOURCES The responsible party for the Hemlock project will ultimately be the homeowners of the individual units. Listed below is the current Land Owners information: GOFAT, LLC Mr. & Mrs. Bernard Goldstein 160 Tamarack Avenue Carlsbad, CA 92008 (760) 729-6892 7.0 SUMMARY & CONCLUSIONS This SWMP has been prepared in accordance with the City of Carlsbad and the County of San Diego Storm Water Standards Manual. This SWMP has evaluated and addressed the potential pollutants associated with this project and their effects on water quality. A summary of the facts and findings associated with this project and the measures addressed by this SWMP are as follows: The beneficial uses for the receiving waters have been identified. None of these beneficial uses will be impaired or diminished due to the construction and operation of this project. The Hemlock project will not significantly alter drainage patterns on the site. Current runoff sheet flows easterly into Hemlock Avenue. Proposed drainage facilities will mitigate runoff to a discharge point (sidewalk underdrain) and into Hemlock Avenue. The proposed project will only slightly increase the amount of run-off leaving the site. (Existing Q=0.68cfs, Proposed Q0.79cfs). Landscaping, planter boxes and pervious surfaces will be incorporated into the design as shown on project plans. The proposed construction and post-construction BMPs address mitigation measures to protect water quality and protection of water quality objectives and beneficial uses to the maximum extent practicable. Storm Water Management Plan (SWMP) Hemlock Project, MS 05-19/SOP 05-09/CP 05-10/CDP 05-25 APN: 204-251-06 ATTACHMENT A Vicinity Map HEMLOCK PROJECT THOMAS BROTHERS PAGE 1106 SITE S ç$L 0 A -v 70 0, 0 VICINITY MAP NOT TO SCALE ATTACHMENT A ALTA CONSULTANTS PLANNING ENGINEERING SURVEYING 4901 Koren Blvd. Ste. 409 San Diego. C6 92117 (858) 681-8101 Fax (858) 681-6138 Storm Water ManagOment Plan (SWMP) Hemlock Project, MS 05-19/SOP 05-09ICP 05-10/COP 05-25 APN: 204-251-06 ATTACHMENT B Site Plan and BMP Drawing Stomp Water Management Plan (SWMP) Hemlock Project, MS 05-19/SOP 05-09/CP 05-10/CDP 05-25 APN: 204-251-06 ATTACHMENT C Tentative Map Exhibit P_4z_~LL MAP NO. MS 05-19 LU z -J - F- rK LU 0- 0 1 ry 26 MIN. TW56.5 ,EX. FENCE U5) - \I/To REMAIN Qu oc$ H OIl PROPO. U J'Li EXIST. FG= 51 .0 LU < FG=50.5 EXISTING 1.5' EXIST. 5 RETAINING WALL FG-49.7 ON ADJACENT PROPERTY TO REMAIN (I) LU° "—UNDERGROUND I IMflP(ROUND I 0 d GARAGE WALL 0 11 CIL LA_Ip WALL ATED RAIN NOT LcA QffA=4 TO SCALE FEET ) 1 inch 10 ft. \ \\ \\ $v 77 jErgLoc1&mztf2Nj.. \\S , , \v LOT 6 IN BLOCK E OF PALISADES, IN THE CITY OF CARLSBAD, COUNTY çy....i X. 6' (50 OF SAN DIEGO, STATE OF CALIFORNIA, ACCORDING TO MAP THEREOF ME \ ,t A T 40.0 BRW NO. 1747, FILED IN THE OFFICE OF THE COUNTY RECORDER OF SAN WOOD FENCE DIEGO COUNTY, FEBRUARY 5, 1923. v -' 1TO BE REMOVED SEWER V 'S ' CLENOUT \LIS -r & BE REMOVED) \\ EX. OVERHEAD —IY THE BASIS OF BEARING FOR THIS PROJECT IS THE CALIFORNIA \ UTILITIES COORDINATE SYSTEM - 1983 ZONE VI, 1991.35 EPOCH, NORTH EX. POWER (To REMAIN) ) AMERICAN DATUM OF 1983 (NAD83), GRID BEARINGS BETWEEN POLE (PROTECT) r- STATION 130 AND STATION 141 AS SAID COORDINATES ARE PUBLISHED IN THE CITY OF CARLSBAD SURVEY CONTROL NETWORK -- S' ESTABLISHED BY RECORD OF SURVEY NO. 17271, FILED IN THE OFFICE X. PAVING WOW FENCE OF THE SAN DIEGO COUNTY RECORDER ON FEBRUARY 8, 2002. ' 5&.50 TW -J ( W/COtJ CRETE Er a 53.00 TRW ç. I FOOTIN (TO 40.50 RW > 'TING TWO s J, REMAIN)\ FOUND CPS CONTROL POINT NO. 141. 2.5" BRASS DISC STAMPED CV q STORY BUILDING N I CLSB-141 L.S. 6215, PER CITY OF CARLSBAD RECORD OF SURVERY 6' PRIV.ACYALL '/J .AV\ "Ky NO. 17271. N=1998491.11, E=6226887.85. DATUM: 26,7 MSL SUROUNDING P ERTY E. M\\.A \\ S \ 50 .20 TRLE \ \ (TO BE\ DEMOLISHED) EM' \\I CATCH BASIN PROJECT ADDBESS EXISTING SHED 130 HEMLOCK AVENUE N 5 CARLSBAD, CALIFORNIA, 92008 APPROX. 1 c?4, \\ / S Q THOMAS BROS 1106-E7 FF= 45.50 " Q DDI') Tf 1 11 ATA 1'. LEGEND: IT ff J57AQh PROPOSED LOT LINES---------------------------------------------- EXISTING CONTOURS ----------------------------------------------- EXISTING CURB & GUTTER ------------------------------------------- RIGHT OF WAY -------------------------------------------------- ROW EXISTING WATER MAIN --------------------------------------------- —W EXISTING WATER SERVICE------------------------------------------ EXISTING SANITARY SEWER MAIN --------------------------------------- —S EXISTING SANITARY SEWER LATERAL------------------------------------ EXISTING OVERHEAD UTILITY/POWER LINES ----- --- ------------------------—OHE EXISTING FREESTANDING/RETAINING WALL-------------------------------- EXISTING CONCRETE------------------------------------------------' PROPOSED RETAINING WALL------------------C-2, C-4 ------------------ PROPOSED , HIGH-VISIBILITY WALL/FENCING (MAX 42" HIGH)----------------------- ° PROPOSED CONCRETE ---------------------------------------------- DRAINAGE FLOW DIRECTION -------------------------------------------- PROPOSED SLOTTED DRAIN FOR BASEMENT RUNOFF ------------------------ PROPOSED STORM DRAIN PROPOSED CATCH BASIN------------------------------------------- PROPOSED SIDEWALK UNDERDRAIN-------------------------------------- - - ALL 3.5' FENCE/WALLS WITHIN FRONT YARD SETBACK TO BE HIGH ViSIBILITY MATERIALS bi -. (PLEXIGLASS, WROUGHT IRON OR SIMILAR)1 1~ HEMLOCK PROJECT Ie %Yi - DEMOLISH EXISTING TWO-STORY RESIDENTAL STRUCTURE, V QTkI(' TI- cTrPv\ 2' 56.50 \TW SHEET TITLE: CONSTRUCT TWO ATTACHED RESIDENTIAL UNITS, UNDERGROUND I I 7 2 53.50 TRW \ PARCEL MAP GARAGE ACCESS FROM HEMLOCK AVENUE. APARTMENT BUILDING S 40.50 BFW APPROX. FF45.5O 7 \ '\11 N SERVICES FOR WATER, SEWER, GAS, ELECTRICAL, TELEPHONE, 7 / 4 cf .# CABLE & ECT WILL BE ADDED OR UPGRADED AS NECESSARY / 50SIN 4 ,\S\5 () .::\\ .. 6.5PRIVACY WALL TYPE OF CONSTRUCTION: TYPE 5 NON-RATED 77 VV<'EXGARAGE I SURROUNDING PROP RTY REF'ERENcE DPAW1WGS: 7 7 O \,. N END'6' WALL PARCEL MAP NO. 19382, MAP NO, 1747, 5/- it "V ' 7 "t APPROX. 1 '16 çØ '" " \\ VI $). \ BEGIN 3.5' WALL* ç ASSESSOR'S MAP 204, PAGE 25 ,' • ,.z" FF=45.50 \ \. \) ' o 54.00 . CITY OF CARLSBAD DRAWING NO. 124-6 / ,v" 50 # \\ ~b 50 TRW \\ \ 11 XEXISTING 7 .50 BRW \\ \ 0 CH BASIN APPROX p\ \ SEWER CLEANOUT BEST MANAGEMENT PRACTICES (BMPs) SHALL BE USED ON SITE \ \FC= 27 7 I \ STORM" DRAIN N 0. DURING AND AFTER CONSTRUCTION TO ENSURE NO POLLUTANTS ARE \ , \ Ocs 7 ¶.,, \ V z LEANouT DISCHARGED INTO THE EXISTING STORM DRAIN SYSTEM IN HEMLOCK 2 Sç' 0 O . EX. 2" TM 7/- AVENUE FLO-GARD CARTRIDGE FILTERS SHALL BE INSTALLED ON ALL DR PROPOSED INLETS COLLECTING STORM WATER. 7S \ * 50 W P OBE L ON ADJACENT 6' HIGH WALL I ISER TO O50 'TRW*c C, Al O 4 54.00 ERELOCA ZE 7 PROPERTY TO RE : : I STORM DRAIN -dwy 5X, STREET LIGHT CURB OUTLET 01 PREPEDBY ,77 ENDWALL ELEC.BOX Firm: ALTA CONSULTANTS / BEGIN 3.5' FENCE* 7 \ 7 . ' S S . o EX ATER METER A Name BARTOLOME J PASTOR IRyV " Q ç 5 0 & LA ERAL LL 35' FENCE/WA 1$'WITHIN 40.50 BRW (858) 581-6101 N0.38606 OZ- cl, LICH OR SIM EX. POWI;R 52.50 TW PARKING 40.50 BRW C 'V6 Lt 13 DRIVEWAY TO BE REPLACED V NE W* FRONTYARD SE K TO BE W ER METER N / BARTOLOME J. PASTOR DATE: 2" STO &VI E (UNIT ROE 38606, EXP. 3/31/2007 \, . LATERAL REMOVED DRAIN TO BE 7) NEW SEWR 7 EX. STORM DRAIN (UNIT 2) CURB OUTLET TO SEWER MH / N - BE REMOVED N7 I E = 41.1 5 7 \ 7, 13' DRIVEWAY TP 101 VC o p') - ELEVATED PROPOSED HOUSE (UNIT 2) PATIO ,- ' 5' - - 0 ELEVATED FF'=54.00 FF54.00 (. CL 'I'IIII'!'I'I'II'I'I'II'IIIIII'II'I'I'I'IIIIIIIlIII'I 'I'II'IIIIIIIIIIIIIIIIIIII,I ,I!I ,I!,IIII, FG= I 0.50 HEMLOCK AVENUE T1, ON SCALE 1"=10' 1. EXISTING ZONING : MULTIFAMILY RESIDENTIAL (R-3) & COASTAL ZONE 2 GENERAL PLAN RESIDENTIAL HIGH (RH), 15-23 UNITS/ACRr 18 NAD 83 COORDINATE INDEX N1998492, E6226887 GROWTH CONTROL POINT OF 19 UNITS/ACRE 19 TOTAL SUBDIVISION CROSS AEA 5663 Q 0 13 AC 3 PROPOSED ZONING SAME AS EXISTING 20. TOPOGRAPHY PER ALTA CONSULTANTS (SURVEYED FEBRUARY 11, 2004) 4. PROPERTY IS LOCATED WITHIN THE NORTH BEACH STUDY AREA. 21. STREET IMPROVEMENTS: REPLACE EXISTING CURB, GUTTER AND SIDEWALK PROPOSED DENSITY: 15.3 DWELLING UNITS PER ACRE. AS NECESSARY, REPLACE EXISTING DRIVEWAY WITH NEW 21' DRIVEWAY NUMBER OF PROPOSED UNITS: 2 22. EASEMENTS PER TITLE REPORT NO. 58002994-PO1 DATED MAY 19, 2005: NUMBER OF PROPOSED LOTS : 1 *AN EASEMENT LOCATED AT THE SOUTHWESTERLY 6 FEET AND THE NORTHWESTERLY 6 FEET OF LOT 6, GRANTED TO SAN DIEGO NUMBER OF PROPOSED ON-SITE PARKING SPACES: 5 CONSOLIDATED GAS & ELECTRIC FOR -THE PURPOSE OF PUBLIC UTILITIES, 9 ASSESSOR'S PARCEL NUMBERS' 204-251-06 INGRESS & EGRESS, RECORDED JULY 10, 1923 IN BOOK 961, PAGE 3 OF DEEDS OF THE SAN DIEGO COUNTY RECORDERS OFFICE. 10, SEWER SERVICE: CITY OF CARLSBAD 23. EXISTING VEGETATION CONSISTS OF TREES, BUSHES AND PLANTERS, WATER SERVICE: CARLSBAD MUNICIPAL WATER DISTRICT ALL EXISTING LANDSCAPING WILL BE REMOVED DURING CONSTRUCTION. NEW LANDSCAPING, POTS AND PLANTERS WILL BE INSTALLED. FIRE PROTECTION: CITY OF CARLSBAD APPROXIMATELY 10% OF THE SITE AREA WILL BE UTILIZED FOR 13, GAS AND ELECTRIC: SAN DIEGO GAS & ELECTRIC COMPANY LANDSCAPING/PLANTING PURPOSES. 5 TELEPHONE SERVICE. SBC ' 24, EXISTING FIRE HYDRANT LOCATED APPROXIMATELY 90' DUE WEST OF THE PROPOSED PROJECT ON HEMLOCK AVENUE. CABLE SERVICE: ADELPHIA SCHOOL DISTRICT: CARLSBAD UNIFIED 17, PROPOSED EARTHWORK: URTECTURE. PLATFORM CUT — 2100 CY IT FILL = N/A FRONT ' LU - MR. JORGE OZORNO EXPORT = 2100 CY LU REAR 10 >- 1761 HOTEL CIRCLE SOUTH #350 Z F- SANDIEGO, I ./-NN SIDEYARD 25% OF LOT WIDTH flUIN. O I LUU / )UO FAX: (619) 501-9876 WATER DEMANDS TABLE AVERAGE DAILY DEMAND (GALLONS PER DAY) 558 A VERA GEDAILYDEMAND(GPM) 0.39 PEAK DOMESTIC WATER DEMAND (GPM) 0,62 MINIMUM FIRE FLOW (GPM) 45.5 A VERA GESEWERGENERA TION(GPM) 0.3 124-6 7 7 7, oc - 7/- \ 7 UTILITIES OVERHEA D 7TF1 Trvrnrl #'1W&TZ1 /A nr rI'A ,rm. - r7 11<1' EX. POWER POWER \ POLE 7 5 -7' 25' I 25' 11 MR. ED MULLEN : MULLEN CONSTRUCTION 2890 PlO P100 CARLSBAD, CA 92008 (760) 434-2233 LU 3 ' 16' 16' - - p ,,-EXISTING AC PAVING LU 0 20,5' MIN. z _______________- 8' (1)-S LU ry TW=56.5 o EXISTING 6' 0 o RETAINING WALL ' ON ADJACENT \ -:4 PROPOSED PROPERTY \ _FG=50.5 TO REMAIN XIST.FG=50.20 EXIST. FC=45.50 -5 5. * UNDERGROUND 0 GARAGE WALL -.LD o '-.(flU) d Revision 3: - =54 3, Li MR. ED MULLEN STREETDATATABLE STREETNAME CLASSIFICATION AD T(VEHICLES) DESIGNSPEED(MPH) R/W(FT) HEMLOCKAVENUE 2 LANE- RESIDEN7IAL 16 -- 50 Revision 1: AUGUST17,2005 JULY 15, 2005 II PERFORATED Revision 2: SEPTEMBER 8, 2005 WALL DRAIN NOT TO SCALE Original Date: Sheet F- ci LU CL 12' MIN. LU I ,TW56.5 C/) 14 2' — O 00 r L() OIl PROPOSED _____MEd, FG=50.5 U- EXIST. FG=49.6 ¶ LU 0 Cl- EXIST. F_45.50 UJ< EXIST. 3.5' RETAINING WALL TO BE REMOVED & REPLACED WITH NEW UNDERGROUND O U- GARAGE WALL ILC&L_$ETLQW PERFORATED WALL DRAIN NOT TO SCALE >< 5'I EXISTING CURB —EXISTING S/W & GUTTER NOT TO SCALE of 1 ht.1LUIJ\ LD/-U HE Is Ir CK PR-*r% T L-7 C r-, mLu U u -v-j HYDRuLOGY MAP cy EX. 6' SDG&E EASEMENT WOOD FENCE (Tr Mr7 PFKAMr7ro -V 7 7 7 7 7 7 / 7 6' 7 7 7 7 7 \ 7 7 7 V7 - 7 7 56.50 TW,, 53.50 TRW ÔOBRW 7 V SEWER CLEANOUT (To BE REMOVED) 56.50 TW 53.00 TR' WOOD FENCE W/CON CRETE FOOTING (TO REMAIN) 6' PRIVACY WALL SURROUNDING ,, 7 VICINITY MAP NO SCALE EXISTING SHED APPROX. \ FF=45.50 TG=50.50 IE=49.75 0 \\ VI WATERSHED AREA DESIGNATION WATERSHED AREA (ACRES) EXISTING THREE STORY APARTMENT BUILDING APPROX. FF=45.50 A 0.13 56.50 TW 53.50 TRW 40.50 BRW 10 6' PRIVACY WALL \ SURROUNDING PROP RTY Z I lool 7 -*~z V DESIGNED RUNOFF APPROX. FF=47.00 50.50 TRW 40.50 BRW CH BASIN /'IEt=49.65 50.25 ,—EX. 1' RAISED / PLANTER ft STORM DRAIN RUNOFF FLOW DIRECTION \ \\\ 'I0, - V M 7 PACBELL RISER TO BE RELOCATED ,.—STORM DRAIN CURB OUTLET EX. STREET LIGHT 'vs \ ELEC. BOX EX. MATER METER -*KLL 3.5' FENCE/WAU5 & LA\ERAL -IMTHIN , FRONT YARD SETRAtK TO BE S)DEWA c< HIGH 1SI8IUTM7ATERIALS IDE1DAtN !ES (PLEXIGLASS('WROUGHT IRON 91..ET 1 = - OR SIMJL) V EX. POWER POLE 0 / V ER METER & 515t VIE (UNIT 2) — 47.01 ed dwy END 6 WALL BEGIN 3.5- FENCE- 52.50 TW 49.00 TRW 40.50 BRW EX. 6' SDG&E EASEMENT EX. GRAVEL PARKING 52.50 TW 49.00 TRW 10 CURB OUTLET MH 13' DRIVEWAY IE=41.15V EX. 4" C.I. 1001, WATER MAIN Q PER DWG 124-6 0 V V 7 fl\/PI-WAE J) EX. POWER POLE V7 -V - HEMLOCK 257-08 Storm Water Management Plan (SWMP) Hemlock Project, MS 05-19/SDP 05-09ICP 05-10/CDP 05-25 APN: 204-251.06 ATTACHMENT D Hydrology Calculation Tables PROPOSED HYDROLOGY CALCULATIONS Project: Hemlock Project Precipitation (P6) = 2.5 Location: Hemlock Avenue, Carlsbad Soil Classification: "D" Date: September 8, 2004 Storm Frequency: 100 years Remarks Node 1 ->2 Area (Al) = 0.03 Acres Driveway runoff to slotted drain and sump pump Travel Distance (L) = 65 Feet Slope (S) = 14.0% Time of Concentration (Tc) = 1.51 Minutes Intensity (I) = 14.25 Inches/Hour Runoff Coefficient (C) = 0.85 Designed Runoff (Q) = 0.36 C.F.S. Pumped to Node 3-> Node 4 and outlet to Hemlock Ave Node 3 ->4 Area (A2) = 0.04 Acres Roof runoff and front patio area Travel Distance (L) = 62 Feet Slope (S)= 1.0% Time of Concentration (Tc) = 3.54 Minutes Intensity (I) = 8.23 Inches/Hour Runoff Coefficient (C) = 0.85 Urban Area Watershed Designed Runoff (Q) = 0.28 C.F.S. Runoff to Hemlock Ave. at Node 4 via 6" PVC storm drain. Node 5 ->6 ->3 Area (A3) = .06 Acres Runoff through landscaping at rear of property, roof runoff, some paving/patio areas Travel Distance (L) = 75 Feet Slope (S) = 1.0% Time of Concentration (Tc) = 3.90 Minutes Intensity (I) = 7.74 Inches/Hour Runoff Coefficient (C) = 0.85 Urban Area Watershed Designed Runoff (Q) = 0.39 C.F.S. Runoff to Hemlock Ave. Concentration @ Node 4 Total Runoff at Node 4 (Qt) = 1.03 C.F.S. Outlet to Hemlock Ave, via proposed sidewalk underdrain, 2-3" outlet pipes. Storm Water Management Plan (SWMP) Hemlock Project MS 05-19/SDP 05-09ICP 05-10/CDP 05-25 APN: 204-251-06 ATTACHMENT E 85th Percentile Precipitation Map : 71 It San Diego County ..., i 85th Percentile Draft 8/7/2003 / Legend / \9 7 DPW 0 S 012 4Mies V 51m Storm Water Management Plan (SWMP) Hemlock Project, MS 05-I9/SDP 05-09ICP 05-10/CDP 05-25 APN: 204-251-06 ATTACHMENT F Formula Sheet HYDROLOGY & HYDRAULIC REFERENCE FORMULA TIME OF CONCENTRATION: Natural Watershed - County Dwg.: Appendex X-A T - ,11.9L 3 Where: Tc = Minutes ± Initial 10 Minutes C - H L = Miles of \Vaterhed Along Natural Channel H = Difference in Elevation along effective slope Line 1.8(1.1 - C) fL Urban Area Overland Fow Fig. 3-5 Tc = Where: Tc = Minutes C = Runoff Coefficient L = Overland Travel Distance S = Effective Slope (%) INTENSITY (Ins./hr.): 1=7.44P D 464 6 Intensity-Duraton-Frequency - County Design and Procedure Manual (Appendix XI-A) Where: I = Intensity (ins./hr.) P6 = 6 hours Precipitaton in (Ins.) D =Duration in minutes MANNING'S FOR PIPE: (Designed Runoff) = 0.462d 3S1/2 .. Basic Formula: For Capacity Calculation, S should be Sf- for Pipe Flowing Full So - for Pipe Partially Full Q = Handbooks for Hydraulics by n Baxter & Kings = 0.0737 S fl Pipe on channel flow 2arccos (1 - Q 9. 739DrHe 'j Storm Water Management Plan (SWMP) Hemlock Project, MS 05-19/SOP 05-09/CP 05-10/COP 05-25 APN: 204-251-06 ATTACHMENT G Fossil Filter Details FOSSIL FILTER CATCH BASIN INSERT INSTALLATION DETAIL FLO-GARD (PRIVATE) POST CONSTRUCTION WEAKLY INSPECTIONS OF THE FOSSIL FILTERS IS REQUIRED, INSPECTION IS ALSO REQUIRED AFTER RAIN. IMMEDIATE REPLACEMENT OF FILTER IS REQUIRED WHEN FILTER IS SATURATED WITH GREASE, OIL AND/OR SILT. APPLICA TION CHART* 'MODEL I I I I NO. Inlet I.D. I Grate O.D. I COMMENTS I FGP-12 I 12' x 12' I 14' x 14' I GRATED INLET INLET GRATE __\\\ Flo—Gard Filter inserts are designed to fit catch basins with approximate dimensions shown. FLO—GARD INSERT (SEE APPLICATION CHART) CATCH BASIN SCALE: NONE NOTES: Flo—Gard Filter body is prefabricated from polypropylene woven mono filament geo textile. All metal components shall be stainless steel (Type 304). Refer to application chart for catch basin and filter sizing. Filter medium shall be Fossil Rock, installed and maintained in accordance with manufacturer recommendations. Refer to Manufacturer's recommendations for maintenance program. Flo—Gard inserts may be installed without adsorbent pouches during course of construction as a sedimentation control device. After construction, remove the sediment and install the absorbent pouches. See cross—section detail. Approximate yearly maintenance costs: $500 ALTA CONSULTANTS PLANNING ENGINEERING SURVEYING 4801 Morena Blvd.. St.. 409 San Diego. Ch 92117 (968) 681-6101 Fix (858) 691-6138 FloG&d4P1us Filter installed -Model No.- Inlet ID .(ln x In). .Grata CD (In x In) Solids Storage c!_() Filtered Flow (cfs) Total Bypass . Cap (cfs) FGP:12Fr12X12_ 14x14 03 0.4-_.....28 - FGP-1530F .15x30 .16x36 2.3 .1.6 6.9 FGP-16F .16x16 .18x18 0.8 0.7 4.7 FGP-18F .18 x 18 20 x 20 0.8 0.7 4.7 FGP4822F 20x24 .18x22 2.1 .1.4 5.9 FGP-1824F .16x22 ,20x24 .1.5 .1.2 5.0 FGP-1836F .18x36 .18x40 2.3 .1.6 6.9 FGP-2024F 20x24 22x24 1.2 .1.0 5.9 FGP-21F 22x22 24x24 2.2 .1.5 6.1 FGP-2142F 21x42 26x42 4.3 2.4 9.1 FGP-24F 24x24 26x20 2.2 .1.5 6.1 FGP-2436F 24x36 24x40 3.4 2.0 8.0 FGP-2445F 24x45 26x47 4.4 2.4 9.3 FGP-2448F 24x48 26x48 4.4 2.4 9.3 FGP-28F 28x28 30x30 2.2 .1.5 6.3 FGP-30F 30 x 30 30 x 34 3.6 2.0 8.1 FGP-38F 36x36 36x40 4.6 2.4 9.1 FGP4648F 36x48 40x48 6.8 3.2 .11.5 FGP48F 48x48 48x52 9.5 3.9 .13.2 MOlES: 1. ccllfonpi$crthdi,gflbifr bypez& I R ,dflow,.hithsdes .eEstyfaa2. RDCsxd#Phm Citch Bub RIaieavIe Iii the ndd e (use buss)arthciuns CII taT h CII CIIiII ulus lnsCI. R diusI3t.Inee.bIusdd bs used Ii corwiIIon edth e iidarn.dui.... pmg.n RIuts -..n.o.115dmwwwmgwdeIMee. US IWENT fLO-GARDTM +PLUS CATCH BASIN FILTER INSERT (Frame Mount) FLAT GRATED INLET Ki(S(m Bitelpitses Inn, Saite Rosa. CA (800) 579.8819 LZU 12"x 12"BROOKS BOX CATCH BASIN CROSS-SECTION DETAIL (PRIVATE) ,- 14" X 14" CRATE / W/FOSSIL FILTER EXISTING PAVING / 1. ,•• •'.:.. •á..4.:4 4 .D - STANDARD CATCH 18" BASIN SECTION -OUTLET PIPE CONCRETE BOTTOM SCALE: NONE ALTA CONSULTANTS PLANNING ENGINEERING SURVEYING 4901 Morons Blvd. Ste. 409 San Diego, C& 92117 (858) 581-6101 Fax (858) 681-6138 Storm Water Management Plan (SWMP) Hemlock Project, MS 05-19/SDP 05-09ICP 05-10/COP 05-25 APN: 204-251-06 ATTACHMENT H Sample Pollution Prevention Fact Sheets (County SD) REFERRAL NUMBERS In For more information on stormwater management (888) 846-0800 At For information on recycling, composting and household toxics (877) R-1 Earth (877) 713-2784 To schedule a presentation for your community group or organization (888) 846-0800 For residential gardening tips or questions please contact the Master Gardener Program (858) 694-2860 In For a daily update on beach and bay closures (619) 338-2073 STORM WATER POLLUTION PREVENTION project clean water "dean water through local commitment and action" YARD WORK Call us for more information: (888) 846-0800 or visit us at our web site: www.sdcdpw.org or www.projectcleanwater.org Ies against the law to Ie' pollute storm water. J ( LANDSCAPING GARDENING PEST CONTROL County of San Diego Watershed Protection Program County Code §67.805 prohibits the discharge of anything but rainwater to the stormwater conveyance system or receiving waters. Pdnted on reqded paper 003 WHAT IS STORM WATER POLLUTION? When rain flows over streets and other surfaces, it picks up pollutants and carries them into the stormwater conveyance ("storm drain") system. This system Is designed to prevent flooding by transporting water away from developed areas. However, this water Is not filtered or treated, and all the contaminants it contains eventually flow to our streams, lakes, and ocean where we swim and fish. Once there, polluted runoff can harm wildlife and habitats. In some cases, it can even cause beach closures or make fish and shellfish unsafe to eat. Wastes from yard work are among the many common stormwater pollutants that can degrade water quality. Other examples include paint, oil and automotive fluids, construction debris, pet waste, litter, pool chemicals, and dirty wash water. ONLY RAIN IN THE STORM DRAIN HOW DOES YARD WORK POLLUTE STORM WATER? CHEMICALS The "chemical only" approach to pest control -. often causes more problems than it solves. Over 90% of the insects In your lawn and garden are not harmful. Many gardeners use pesticides, herbicides, and fertilizers at over 20 times the rate necessary, greatly increasing polluted runoff. ORGANIC WASTES :. Grass clippings, leaves, and ... tree trimmings swept or blown Into streets and gutters carry chemicals into our waterways and can dog catch basins, increasing the risk of flooding. Once they settle into water bodies, these materials begin to decompose, absorbing oxygen fish need to survive. SEDIMENT Soil and dirt washed from yards can also harm aquatic life by clogging the gills of fish, blocking light transmission, lowering water temperatures, and inhibiting photosynthesis. WHAT CAN IDO? Here are some things you can do to keep contaminants out of runoff. GENERAL LANDSCAPING TIPS Schedule big projects for dry weather. Store stockpiles under plastic tarps to protect them from wind and rain. Store pesticides, fertilizers and other chemicals In a covered area. Use plants that require less water. Prevent erosion by planting fast-growing grasses to shield and bind the soil. LAWN and GARDEN MAINTENANCE Don't overwater. Use drip irrigation, soaker hoses, or micro-spray systems. Use curbside yard waste recycling or take clippings to a landfill for composting. Don't blow or rake leaves Into the street or gutter. Avoid hosing down the pavement. Don't overfertilize or apply chemicals near ditches, streams, or water bodies. CHEMICAL ALTERNATIVES Don't kill insects that aren't harmful. Use less toxic products, for example dehydrating dusts (such as silica gel), insecticidal soaps, boric acid powder, horticultural oils, pyrethrin-based Insecticides, bacterial insecticides, and organic or non-toxic fertilizers. Use predatory insects when possible. If you must use a pesticide, use one that Is specifically designed to control your pest (listed on the label). Always read the label and use only as directed. What you do in the yard can directly impact the quality of our local waters. ' When soil, organic wastes, and chemicals leave your yard, they flow directly into streams, lakes, and the ocean where they can harm human health and the environment. - OVERWATERING •g Over watering washes S fertilizers, pesticides, and herbicides into storm drains. In your yard these chemicals kill garden invaders, but when washed into local waters they poison fish and contaminate water. STORM WATER POLLUTION PREVENTION REFERRAL NUMBERS For more information on stormwater management (888) 846-0800 , To reach the County Department of Environmental Health (619) 338-2222 For Information on recycling, 19 composting and household toxics (877)-R-1 Earth (877) 713-2784 To schedule a presentation for your community group or organization (888) 846-0800 •For a daily update on beach and bay closures (619) 338-2073 LJL2 project clean water "dean water through local commitment and action" Call us for more information: (888) 846-0800 Or visit us at our web site: www.sdcdpw.orca or www.orojectcleanwater.org For pet licensing information, visit the Department of Animal Services web site: www.sddac.com PET WASTE '7anges reduce pollution WI Prtnted on — papa County of San Diego Watershed Protection Program WHAT IS STORM WATER POLLUTION? When rain flows over streets and other surfaces, It picks up pollutants and carries them into the stormwater conveyance ("storm drain") system. This system Is designed to prevent flooding by - transporting water away from developed areas. 43 However, this water is not filtered or treated, and all the contaminants It contains eventually flow to our streams, lakes, and ocean where we swim and fish. Once there, polluted runoff can harm wildlife and habitats. In some cases, It can even cause beach closures or make fish and shellfish unsafe to eat. Pet wastes are among the many common stormwater pollutants that can degrade water quality. Other examples include paint, oil and automotive fluids, construction debris, yard wastes, pesticides, litter, pool chemicals, and dirty Wash water. ONLY RAIN IN THE STORM DRAIN WHY IS IT SO IMPORTANT TO PICK UP AFTER YOUR PET? ' ' During rainfall, pet waste left on - lawns, beaches, trails and sidewalks washes into storm drains. These wastes and the - pathogens they contain , (bacteria, parasites, and viruses) end up flowing directly into streams, lakes and the ocean where they can harm human health and the environment. As they decompose, pet wastes - demand a high level of oxygen from water. This demand can kill fish and plant life by reducing the amount of dissolved oxygen available to them. Recent studies have shown dogs and cats are sources of fecal contamination at local beaches. In addition to causing beach closures, this contamination can make people sick with sore throats, Intestinal problems, rashes, ' nausea, and eye and ear infections. County Code §67.805 prohibits the discharge of anything but rainwater to the storrnwater conveyance system or receiving waters. WHAT CAN IDO? I 01 .. The next time you're caught outside in the rain, take a look at what's running off the street, Into the I gutters, and down storm drain inlets. 1 I Clean up pet waste in your yard on a regular basis, to prevent polluted runoff. I, Carry a bag or "scooper" I when you take your pet on walks, to the park or other • public places. Be '- preparedanddeanupthe j •4PT 5 pet waste. Do your part to help keep our water clean' PICK UP AFTER YOUR PET! it's as easy as 1 -2-3 1. Bring bag L..) 2. Clean it up I. Ato 3. Dispose of it - properly (toilet or trash) I. I... RECEiVED OCT 212005 ENGINEERING DEPARTMENT