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HomeMy WebLinkAboutCT 11-01; ROBERTSON RANCH WEST VILLAGE; STORM WATER MANAGEMENT PLAN; 2013-02-15STORM WATER MANAGEMENT PLAN For EL CAMINO REAL WIDENING RANCHO COSTERA CDP 11-10 CT 11-01 SWMP 13-03 Revised: December 10, 2013 Prepared: February 15, 2013 J.N. 10-1307-5 RECEIVED Prepared By: MAR 07 201I O'DAY CONSULTANTS, 1] I 2710 Loker Avenue West, Suite 10NGINEERUtG Carlsbad, CA 92010-6609 (760)931-7700 I (2 George Okay, RCE 32, Exp. 12/31/14 I I I '2 2O// DatS TABLE OF CONTENTS TABLEOF CONTENTS ................................................................................. 1 1. PROJECT SETTING ........................................................................... 3 2. APPLICABLE STORM WATER STANDARDS ...............................4 Storm Water Standards Questionnaire...........................................4 HMP Applicability Determination.................................................4 3. IDENTIFY POLLUTANTS OF CONCERN.....................................4 Identify pollutants associated with type of project/use..................4 Identify watershed, hydrologic unit basin and receiving waters .4 List impaired water bodies.............................................................4 Beneficial uses of receiving water.................................................5 Summarize primary pollutants of concern.....................................6 4. SOURCE CONTROL MEASURES ...................................................6 Description of site activities and potential sources of pollutants.. .6 Stormwater Pollutant Sources and Source Controls......................6 5. LOW IMPACT DEVELOPMENT (LID) DESIGN STRATEGIES ... 6 5a. Optimization of site layout.............................................................6 Setbacks of creeks, wetlands, and riparian habitats.......................6 Minimization of imperviousness....................................................6 5b. Layout and use of pervious surfaces..............................................7 5c. Dispersal of runoff from impervious areas to pervious areas........7 6. INTEGRATED MANAGEMENT PRACTICES (IMP's)..................7 Selection process for IMP's...........................................................7 Sizing factors for IMP's.................................................................7 Geotechnical recommendation on soil infiltration rates................8 Infiltration calculations..................................................................8 7. TREATMENT CONTROL BMP's.....................................................8 8. HYDROMODIFICATION..................................................................8 9. DOCUMENTATION OF STORMWATER DESIGN........................8 Hydrology maps.............................................................................8 BMP Sizing Calculator..................................................................8 Tabulation ...................................................................................... 8 10. BMP FACILITY MAINTENANCE REQUIREMENTS....................9 lOa. Ownership and responsibility of maintenance of BMP's..............9 lOb. Summary of maintenance requiremenmts .....................................9 11. SWMP CERTIFICATION STATEMENTS......................................10 I I I I G:\101307\SWMP\ECR-Widening\IP-Submival #2\SWMP.doc 1 I Li I [-'l I I I I I I I I I I I Attachments: Vicinity map Storm Water Standards Questionnaire Figure 2-1 HMP Applicability Determination Table 2-1: Anticipated and Potential Pollutants San Diego Region Hydrologic Boundary Map 303(d) list for impaired water bodies Table 2-3 Beneficial Uses of Coastal Waters Stormwater Pollutant Sources and Source Control Checklist Figure 2-2 Decision Matrix BMP exhibit BMP Calculator Output Geo soils Recommendation Letter for Bioretention Areas Downstream Channel Analysis by Wayne Chang G:\101307\SWMP\ECR-Widening\IP-Submittal #2\SWMP.doc 2 I I I I I I I I I I I 1 I I I I I I I I I 1. PROJECT SETTING This Storm Water Management Plan was prepared to support the Widening of El Camino Real between Cannon Road and Tamarack Avenue, in the City of Carlsbad. See Attachment 1 for Vicinity Map of the site. Storm water run-off from the site is tributary to Agua Hedionda Creek. I As part of the Future Development for Rancho Costera located to the north, CT 11-01, also known as Robertson Ranch West Village, the City of Carlsbad has required the developer to improve El Camino Real. The improvements consist of widening to a right-of-way width of 126 I feet, with appropriate turn pockets for the future development as well as a median in the center of the street. This improvement encompasses the entire length of the northerly side of El Camino Real between Cannon Road and Tamarack Avenue. The improvements on the southerly side of I El Camino Real are limited to two portions: one portion from just west of Crestview Drive to just east of Lisa Street and another portion west of the projection of Julie Place to just east of Kelly Drive. The existing street is improved to a width of 40 feet from the centerline (except where I shown on the south side of the street). Beginning from the intersection of Cannon Road heading west, existing El Camino Real drains I to a low point. An existing 8'x8' reinforced box culvert conveys storm water from the north to the south side of the street. Heading westerly on El Camino Real towards Crestview Drive, an existing 24" storm drain conveys storm water from the north side to the south side of El Camino I Real and outlets east of Crestview Drive. A curb inlet and storm drain is proposed west of the Crestview Drive intersection to prevent storm water runoff from crossing Crestview Dirve as occurs under existing conditions. Continuing westerly, there is an existing 48" storm drain near I the projection of Julie Place. 58.80 acres of land to the north drains to this existing 48" storm drain and is conveyed to a channel within land owned by Hoffman (APN 207-101-27, 28, and 29). Currently storm water from a portion of El Camino Estates runs onto El Camino Real. I That storm water combined with storm water from the high point at El Camino Real drain to property owned by Marja Acres, LLC (APN 207-101-24 and 25). To alleviate runoff to property owned by Hoffman and Marja Acres, a series of storm drains and curb inlets are proposed. This I storm drain will serve as Drainage Project BFA of the City of Carlsbad Drainage Master Plan dated July 3, 2008 prepared by Brown and Caldwell. Continuing westerly, 11.5 acres of land to the north drains into El Camino Real. Since the street is superelevated at this location, both sides I of the street drain to the low point to the north, west of Kelly Drive combining with storm water from the Tamarack intersection. The storm water is conveyed to the south via an existing double 8'x4' reinforced culvert box. The proposed storm drain will alleviate impacts to the sensitive I wetland area to the north by conveying storm water to the south side of El Camino Real. There are several opportunities and constraints for storm water flow control and treatment on this site. Constraints include steep slopes and the presence of Soil Type D. Also, the areas of the street that are superelevated as well as the minimal room between the curb and the right-of-way present a challenge for storm water treatment. Opportunities include the use of pervious payers I or pervious concrete in the median, and bioretention with impermeable liners (flow-through planters). I G:\101307\SWMP\ECR-Widening\IP-5ubmitta1 #2\SWMP.doc 1 2. APPLICABLE STORM WATER STANDARDS Storm Water Standards Questionnaire Per the Storm Water Standards Questionnaire (SWSQ), this project meets PRIORITY ' DEVELOPMENT PROJECT (PDP) requirements and must comply with additional stormwater criteria per the SUSMP. (See Attachment 2 for completed SWSQ) HMP Applicability Determination Per Figure 2-1 of the SUSMP, Hydromodification controls are required. (See Attachment 3 for Figure 2-1 HMP Applicability Determination.) It was determined that field investigations would not be conducted pursuant to the SCCWRP channel screening tools. Therefore the site must mitigate peak flows and durations based on a pre-project condition lower flow threshold of 0.1 Q2. 3. IDENTIFY POLLUTANTS OF CONCERN 3a. Identify pollutants associated with type of project/use Per Table 2-1 of the SUSMP (see Attachment 4), the pollutants anticipated for Streets, Highways & Freeways are: Sediment Nutrients (potentially) I Heavy Metals Organic Compounds I Oxygen Trash & Debris Demanding Substances (due to on-site landscaping) Oil & Grease Bacteria & Viruses (potentially) I Pesticides Identify watershed, hydrologic unit basin and receiving waters. The project is located in the Los Monos Hydrologic Subarea (904.31) of the Agua Hedionda Watershed in the Carlsbad Hydrologic Unit in the San Diego Region (Attachment 5). Under both existing and proposed conditions, storm runoff from the El Camino Real Widening is eventually conveyed to Agua Hedionda Creek, and then continues westerly to Agua Hedionda Lagoon. List impaired water bodies According to the California 2006 303(d) list published by the RWQCB (Attachment 6), Agua Hedionda Creek and Agua Hedionda Lagoon are impaired water bodies associated with the stormwater discharge from this project. Agua Hedionda Creek has impairment for manganese, selenium, sulfates, and Total Dissolved Solids. Agua Hedionda Lagoon has impairment for G:\10 1307\SWMP\ECR-Widening\IP-Submittal #2\SWMP.doc 4 U I I I I I Indicator bacteria and sedimentation/siltation. Sites tributary to Clean Water Act Section 303(d) I water bodies require additional BMP implementation. 3d. Beneficial uses of receiving water I The beneficial uses for the hydrologic unit are included in Attachment 7, and the definitions are listed below. This information comes from the Water Quality Control Plan for the San Diego Basin. IND - 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 repressurization. NAV - Navigation: Uses of water for shipping, travel, or other transportation by private, military, or commercial vessels. I REC 1 —Contract 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 I activities, fishing, or use of natural hot springs. REC 2 —Non-Contact Recreation: Includes the uses of water for recreational activities I involving proximity to water, but not normally involving body contact with water, where ingestion of water is reasonably possible. These include, but are not limited to, picnicking, sunbathing, hiking, beachcombing, camping, boating, tide pool and marine life study, hunting, I sightseeing, or aesthetic enjoyment in conjunction with the above activities. COMM - Commercial and Sport Fishing: Includes the uses of water for commercial or recreational collection of fish, shellfish, or other organisms including, but not limited to, uses I involving organisms intended for human consumption or bait purposes. BIOL - Preservation of Areas of Special Biological Significance WARM - Warm Freshwater Habitat: Includes uses of water that support warm water I ecosystems including, but not limited to, preservation or enhancement of aquatic habitats, vegetation, fish, or wildlife, including invertebrates. I EST - Estuarine Habitat: Includes the uses of water that support estuarine ecosystems including, but not limited to, preservation or enhancement of estuarine habitats, vegetation, fish, or wildlife (e.g., estuarine mammals, waterfowl, shorebirds). I MAR —Marine Habitat: Includes uses of water that support marine ecosystems including, but not limited to, preservation or enhancement or marine habitats, vegetation such as kelp, fish, shellfish, or wildlife (e.g., marine mammals, shorebirds). I WILD —Wildlife Habitat: Includes uses of water that support terrestrial ecosystems including but not limited to, preservation and enhancement of terrestrial habitats, vegetation, wildlife, (e.g., mammals, birds, reptiles, amphibians, invertebrates), or wildlife water food and sources. I RARE - Rare, Threatened, or Endangered Species: Includes uses of water that support habitats necessary, at least in part, for the survival and successful maintenance of plant or animal I species established under state or federal law as rare, threatened or endangered. AQUA - Aquaculture: Includes the use of water for aquaculture or mariculture operations including, but not limited to, propagation, cultivation, maintenance, or harvesting of aquatic plants and animals for human consumption or bait purposes. G:\101307\SWMP\ECR-Widening\IP-SubmittaI #2\SWMP.doc 5 MIGR —Migration of Aquatic Organisms: Includes uses of water that support habitats necessary for migration, acclimatization between fresh and salt water, or other temporary activities by aquatic organisms, such as anadromous fish. SHELL - Shellfish Harvesting: Includes uses of water that support habitats suitable or the collection of filter-feeding shellfish (e.g., clams, oysters, and mussels) for human consumption, commercial, or sport purposes. 3e. Summarize primary pollutants of concern The primary pollutants of concern for this project are Sediment, Nutrients, Trash & Debris, Oxygen Demanding Substances, Oil & Grease, Bacteria a& Viruses, and Pesticides. The extensive use of bioretention facilities throughout the site should be a highly effective method of treating Coarse Sediment and Trash, and Pollutants that tend to associate with fine particles during treatment. Bioretention facilities also show medium effectiveness for treatment of Pollutants that tend to be dissolved following treatment. 4. SOURCE CONTROL MEASURES Description of site activities and potential sources of pollutants Potential sources of pollutants on the project site include: On-site storm drain inlets Landscape/Outdoor Pesticide Use Sidewalks Stormwater Pollutant Sources and Source Controls See attachment 8 for Stormwater Pollutant Sources and Source Control Checklist 5. LOW IMPACT DEVELOPMENT (LID) DESIGN STRATEGIES 5a. Optimization of site layout Setbacks of creeks, wetlands, and riparian habitats Minimize impacts to wetlands, or riparian habitats on the site near the low points west of Cannon Road and east of Kelly Drive. Minimization of imperviousness In order to minimize imperviousness, we will utilize porous payers or pervious concrete in the median as well as landscaped median pockets per the City of Carlsbad Landscape Manual. G:\101307\SWMP\ECR-Widening\IP-Submittal #2\SWMP.doc 6 I I I I I I I L I I I I I I I I T Landscape areas between the curb and sidewalks were increased with the use of meandering sidewalks. Meandering sidewalks are located along the easterly right-of-way I north of station 459+00, see Attachment #10. 5b. Layout and use of pervious surfaces I Permeable payers or pavement will be used in the median. Sc. Dispersal of runoff from impervious areas to pervious areas I Run-offs from proposed impervious areas are directed to pervious landscape areas or IMP's. 6. INTEGRATED MANAGEMENT PRACTICES (IMP's) Selection process for IMP's I According to Table 2-2 of the SUSMP, The majority of pollutants of concern for this project can be grouped in the category of Pollutants that tend to associate with fine particles during I treatment. Nutrients also fall under the category of Pollutants that tend to be dissolved following treatment and Trash, Debris, and Sediment falls under the category of Coarse Sediment and Trash. I According to Table 2-3, Infiltration Facilities provide the highest effectiveness for removal of pollutants in all three categories but our site is constrained by impermeable soils. Bioretention I Facilities were chosen extensively throughout the site for their high removal rates for Coarse Sediment and Trash and Pollutants that tend to associate with fine particles during treatment and their medium removal rates for Pollutants that tend to be dissolved following treatment. I Bioretention facilities detain stormwater and filter it slowly through soil or sand and are versatile in that they can be any shape and can be landscaped. The bioretention areas onsite were sized as flow-through planters to treat stormwater as well as limit flow control for hydromodification. P Li Sizing factors for IMP's 1 1) Lower flow threshold determination Field investigations were not conducted pursuant to SCCWRP screening tools. I Therefore, the site must mitigate peak flows and durations based on a pre-project condition lower flow threshold of 0.1 Q2. 1 2) HMP Decision Matrix Li IMP facilities were sized using the Decision Matrices in Figures 2-2. See Attachment 9. G:\101307\SWMP\ECR-Widening\IP-SubmittaI #2\SWMP.doc 7 Geotechnical recommendation on soil infiltration rates Infiltration rates for Type 'D' soil are low, an underdrain and impermeable liner will be utilized in bioretention areas (flow-through planters). See Attachment 12 for geotechnical recommendations for bioretention areas. Infiltration calculations See Attachment 12 for infiltration rate information. Self-retaining areas were not utilized on this site, as soil infiltration rates were anticipated to be low. TREATMENT CONTROL BMP's I Lined bioretention areas (flow-through planters) were sized for both treatment and hydromodification. HYDROMODIFICATION I Lined bioretention areas (flow-through planters) were sized for both treatment and hydromodification. I I 9. DOCUMENTATION OF STORMWATER DESIGN Hydrology maps I Attachment 10 depicts the 1) Existing Impervious Surface on El Camino Real 2) The proposed Impervious Surface 3) Pervious Pavement and Landscaping proposed on Site and 4) the Self- Treating Areas. I BMP Sizing Calculator I Output from the BMP Sizing Calculator is included in Attachment 11. Tabulation See Output from the BMP Sizing Calculator included in Attachment 11. 1 G:\10 1307\SWMP\ECR-Widening\IP-Submittal #2\SWMP.doc 8 I I I I [1 I 1 10. BMP FACILITY MAINTENANCE REQUIREMENTS ba. Ownership and responsibility of maintenance of BMP's The Owner and Developer will be responsible for the maintenance of treatment facilities. Ongoing maintenance will be assured by executing a Permanent Stormwater Quality BMP Maintenance Agreement that "runs with the land." Once HOA established, HOA responsible for maintenance, repairs, etc. I Maintenance Contact: Name I Company Address I Phone lOb. Summary of maintenance requirements I Bioretention facilities remove pollutants primarily by filtering runoff slowly through aerobic, biologically active soil. Routine maintenance is needed to ensure that flow is unobstructed, that erosion is prevented, and that soils are held together by plant roots and are biologically active. I Typical maintenance consists of the following: . Inspect inlets for channels, exposure of soils, or other evidence of erosion. Clear I any obstructions and remove any accumulation of sediment. Examine rock or other material used as a splash pad and replenish if necessary. . Inspect outlets for erosion or plugging. Inspect side slopes for evidence of instability or erosion and correct as necessary. Observe the surface of bioretention facility soil for uniform percolation throughout. If portions of the bioretention facility do not drain within 24 hours after the end of a storm, the soil should be tilled and replanted. Remove any debris or accumulations of sediment. I . Confirm that check dams and flow spreaders are in place and level and that rivulets and charmelization are effectively prevented. 1 . Examine the vegetation to ensure that it is healthy and dense enough to provide filtering and to protect soils from erosion. Replenish mulch as necessary, remove fallen leaves and debris, prune large shrubs or trees, and mow turf areas. When I mowing, remove no more than 1/3 height of grasses. Confirm that irrigation is adequate and not excessive and that sprays do not directly enter overflow grates. I Replace dead plants and remove noxious and invasive vegetation. . Abate any potential vectors by filling holes in the ground in and around the bioretention facility and by insuring that there are no areas where water stands G:\101307\SWMP\ECR-Widening\IP-Submittal #2\SWMP.doc 9 longer than 48 hours following a storm. If mosquito larvae are present and persistent, contact the San Diego County Vector Control Program for information and advice. Mosquito larvicides should be applied only when absolutely necessary and then only by a licensed individual or contractor. 11. SWMP CERTIFICATION STATEMENTS ha. Preparer's statement The selection, sizing, and preliminary design of stormwater treatment and other control measures in this plan meet the requirements of Regional Quality Control Board Order R9-2007-0001 and subsequent amendments. I George QDay, RCE 3014p. 12/31/14 I 2L! • /L !O/ 'Date lib. Owner's statement The selection, sizing, and preliminary design of stormwater treatment and other control measures in this plan meet the requirements of Regional Quality Control Board Order R9-2007-0001 and subsequent amendments. 1 I foll Brothers Date I 1 I I I G:\101307\SWMP\ECR-Widening\IP-SubmittaI #2\SWMP.doc 10 I I I I F7 H d I I I I I I P I I I P [Ti I I I I 1 I I 1 I I I I I I I I I I I I I I I I I I 1 I CITY OF OCEANSIDE SITE CITY OF VISTA L( CITY OF SAN MARCOS CITY OF ENCINITAS '- VICINITY MAP NO SCALE I I I I I C, 3 I CD I I I I I I 1 I I I I I STORM WATER Development Services STANDARDS Land Development Engineering C T Y OF QUESTIONNAIRE 1635 Faraday Avenue CARLSAAD E-34 760-602-2750 www.carlsbadca.gov I I INSTRUCTIONS: To address post-development pollutants that may be generated from development projects, the City requires that new development and significant redevelopment priority projects incorporate Permanent Storm Water Best Management Practices (BMP's) into the project design per the City's Standard Urban Stormwater Management Plan (SUSMP). To view the SUSMP, refer to the Engineering Standards (Volume 4, Chapter 2) a t w w w . c a i l s b p d c a . c i o v / s t a n d a r d s . Initially this questionnaire must be completed by the applicant in advance of submitting for a development application I (subdivision, discretionary permits and/or construction permits). The results of the questionnaire determine the level of storm water standards that must be applied to a proposed development or redevelopment project. Depending on the outcome, your project will either be subject to 'Standard Stormwater Requirements' or be subject to additional criteria called Priority Development Project Requirements'. Many aspects of project site design are dependent upon the I storm water standards applied to a project. Your responses to the questionnaire represent an initial assessment of the proposed project conditions and Impacts. City s taff 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 i n c o m p l e t e . I n 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 h o w t o 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 developme n t a p p l i c a t i o n s f o r t h e s a m e p r o j e c t 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 Section 1 and follow the instructions. When completed, s i g n t h e l b r m a t t h e e n d a n d submit this with your application to the city. SECTION 1 NEW DEVELOPMENT Does your project inset ons or more of the renewing criteria: YES NO Housing subdivisions of 10 or more *vslllna units. Examples: single family homes, multi-family homes, - condominium and apartments CommercIal — areater than 1.acrt Any development other than heavy industry or residential. Examples: hospitals; laboratories and other medical facilities; educational institutions; recreational facilities; municipal facilities; commercial nurseries; multi-apartment buildings; car wash facilities; mini-malls and other business complexes; shopping malls; hotels; office buildlngs; public warehouses; automotive dealerships; airfields; and other lig h t i n d u s t r i a l f a c i l i t i e s . H.aw Industriti Industry. oreatsr than I acre. Examples: manufacturing plants, food processing plants, metal working facilities, printing plants, and fleet storage areas (bus, truck, etc.). K. Automotive reoelr shop. A facility categorized in any one of Standard Industrial Classification (SIC) codes 5013, 5014, 5541, 7532-7534, and 7536-7539 e)Ic Restaurants. Any facility that sells prepared foods and drinks for consumption, including stationary lunch counters and refreshment stands selling prepared foods and drinks for immediate consumption (SIC code 5812), where the land area for development is greater than 5,000 square feel. Restaurants where land development Is less than 5,000 square feet shall meet all SUSMP requirements except for structural treatment B M P and numeric sizing criteria requirements and hydromodification requirements. E-34 Page 1 of 3 REV 1/14/11 I I I I I I I A CITY OF CARLSBAD STORM WATER STANDARDS QUESTIONNAIRE E.34 Development Services Land Development Engineering 1635 Faraday Avenue 760-602-2750 www.carlsbadca.gov REV 1/14/11 Page 2 of 3 I ~~_J I I I E-34 Hillside development Any development that creates more than 5,000 square feet of impervious surface and is located in an area with known erosive soil conditions, where the development will grade on any natural slope that is twenty-five percent (25%) or greater. Environmentally Sensitive Area (ESA)t. All development located within or directly adjacent7 to or discharging directly' to an ESA (where discharges from the development or redevelopment will enter receiving waters within the ESA), which either creates 2,500 square feet or more of impervious surface on a proposed project site or increases the imperviousness of a_ proposed more of its naturally occurring condition. _area _of _project _site _10%_or Park/no lot. Area of 5,000 square feel or more, or with 15 or more parking spaces, and potentially exposed to urban runoff Streeft reaft highways. and frew.vs. Any paved surface that is 5,000 square feet or greater used for the transportation of automobiles, trucks, motorcycles, and other vehicles RetaIl Gas el/ne 0u1.ts. Serving more than 100 vehicles per day and greater than 5,000 square feet Coastal Oay.Joornenf Zon•. Any project located within 200 feet of the Pacific Ocean and (1) creates more than v 2500 square feet of Impervious surface or (2) increases Impervious surface on property by more than 10%. More than f-acre of disturbance Project results in the disturbance of I-acre or more of land and is considered a K Pollutant-generating Development Project4. En*onmentaity Sensitive Areas include but are not limited to it Clean Water Act Section 303(d) Impaired water bodies areas designated as Areas orSpjài Biological Significance by the Slit. Wits' Resources Control Board (Water Quality Control Plan lor the San Diego Bun (1994) and amendments), water bodies designated with the PARE b.neflcial use by the State Water Resources Control Board (Water Quality Control Plan for the San Diego Basin (1994) and sm.ndmsnts) areas designated as preserves or their equivalent under the Multi Speoles Conservation P r o g r a m w i t h i n t h e C i t i e s a n d C o u n t y of San Diego; and any other equivalent environmentally sensitive areas which have been identified by the Copsrntittess. 2'Directly adJ5cen1 means situated within 200 feet of the Envtr an, .ntaly Sensitive Area. 3 01chrging directly b means outflow from a drainage conveyance system that Is compo s e d e n t i r e l y o f f l o w , f r o m t h e s u b j e c t d . v a i o p m e r t i o r r e d e v e l o p m e n t s i t e , a n d not conwangled with 110w from a4acn1 lands. 4 Pollutant-generating Development Projects are those projects that generate polut*nts at levels greater than background levels. In general, these include aS projects that contribute to an exceedanci to an Impaired water body or which create new lrrçteMoua surfaces greater than 5000 square feet and/or introduce new landscaping areas that require routine use of Fertilizers and pesticides. In most cease linear pathway projects that are for infrequent vehicle use, such as emergency or maintenance access, or for pedestrian or bicycle use, are not considered Pollutant-generating Development Project, if they are butt with pervious surfaces or if they sheet flow to surrounding Pervious surfaces. INSTRUCTIONS: If you answered YES to ANY of the questions above, your project Is subject to Priority Development Project requirements. Skip Section 2 and please proceed to Section 3. Check the meets PRIORITY DEVELOPMENT PROJECT requirements box in Section 3. Additional storm water requirements will apply per the SUSMP. If you answered NO to ALL of the questions above, then please proceed to Section 2 and follow the Instructions. I I I I I I I Eli I I Thai Box f& CRY Us. O REV 1/14/11 1 I I I I I I I I I I I I I I I I I I SECTION 2 SIGNIFiCANT REDEVELOPMENT INSTRUCTIONS: Complete the questions below regarding your project YES NO Project results in the disturbance of 1-acre or more of land and is considered a Pollutant-generating Development Project '7 INSTRUCTIONS: if you answered NO, please proceed to question 2. It you answered YES, then you ARE a significant redevelopment and you ARE subject to PRIORITY DEVELOPMENT PROJECT requirements. Please check the 'meets PRIORITY DEVELOPMENT PROJECT requirements" box in Section 3 below. Is the project redeveloping an existing priority project type? (Priority projects are defined in Section 1) INSTRUCTIONS: If you answered YES, please proceed to question 3. If you answered NO, then you ARE NOT a significant redevelopment and your project is subject to STANDARD STORMWATER REQUIREMENTS. Please check the 'does not meet POP requirements" box In Section 3 below. Is the work limited to trenching and resurfacing associated with utility work; resurfacing and reconfiguring surface parking lots and existing roadways; new sidewalk; bike lane on existing road and/or routine maintenance of damaged pavement such as pothole repair? Resurfacing/reconfiguring parking lots is where the work does not expose underlying soil during construction. INSTRUCTIONS: If you answered NO, then proceed to question 4. If you answered YES, then you ARE NOT a significant redevelopment and your project is subject to STANDARD STORMWATER REQUIREMENTS. Please check the "does not meet POP requirements' bo x in Section 3 below. will your redevelopment project create, replace, or add at least 5,000 square feet of impervious surfaces on existing developed property or will your project be located within 200 feet of the Pacific Ocean and (1) create 2500 square feet or more of impervious surface or (2) increases impervious surface on the property by more than 10%? Replacement of existing impervious surfaces includes any activity that is not part of routine maintenance where Impervious material(s) are removed, exposing underlying soil during construction. INSTRUCTIONS: If you answered YES, you ARE a significant redevelopment, and you ARE subject to PRIORITY DEVELOPMENT PROJECT requirements. Please check the "meets PRIORITY DEVELOPMENT PROJECT requirements" box In Section 3 below. Review SUSMP to find out if SUSMP requirements apply to your project envelope or the entire project site. If you answered NO, then you ARE NOT a significant redevelopment and your project is subject to STANDARD STORMWATER REQUIREMENTS. Please check the "does not meet POP requirements" box in Section 3 below. - iur O5IJflIUUI1 5 q on r SECTION 3 QUESTIONNAIRE RESULTS My project meets PRIORITY DEVELOPMENT PROJECT (POP) 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 Row control (hydromodification) requirements may apply to my project. Refer to SUSMP for details. C] 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 tow impact development strategies throughout my project. Applicant Information and SIgnature Box Address: ç Assessor's Parcel Number(s): ?7co &'yLt1 ((1f ZO ' O(O_ &IO Applicant Name: I Applicant Title: F - —- ?R!TENT ApplantSlnur-- Date: CITY OF CARLSBAD STORM WATER STANDARDS QUESTIONNAIRE E-34 Development Services Land Development Engineering 1635 Faraday Avenue 760-602-2750 www.carisbadca.gov E-34 Page 3 of 3 I I I I I I 1 I I I I U I I I I I I SECTION 2: IDENTIFY POLLUTANTS, BMP SIZING AND SELECTION Is Project a I Proper Et it ICA ergy Dissipation Pe-design Energy Provided? Oici alien System I Project e__iDoes 1--increase lmporseoa 4. Dens Project 1K' Increase UnmOigated Peak I ones Project 7 I < Directly Discharge to '- '. Exempt System? I Ell ,`d. Does Project <'Directly Discharge to Et a. Does Stabilliz d 7. Does Project Directly E: 4 --!-L'~C.n-4ywwe have C:pacay ischarge to Stabilized Convvywnce For Ultimate 0, 1 to Exempt System? flo ,ES 9 Does Project I Determine Dom in , ofPrralysis If, Is Project Urban 110 12. Does Stabilized Et Conveyance Extend Past so of Analysis! and &,entually 13. Does Cumqlativ~,-,Domain I uture Impacts Represent 3% — Impersious ,5ce3 HMP Ecempt 1 14. Hythomodicarion Controlt Require of Decision Oto Matrix Figure 2.2 of Decision Matrix] I FIGURE 2-1. HMP Applicabilir Determination* refer to expanded HNIP exemption criteria below for justifications required on each node I 30 of City Carlsbad SUSMP January 14, 2011 - I I I I H I E U L P I I I I I I I General Pollutant Categories Trash Oxygen Bacteria Priority Project Heavy Organic & Demanding Oil & & Categories Sediment Nutrients Metals Compounds Debris Substances Grease Viruses Pesticides Detached Residential X X X X X X X Development Attached Residential X X X P(1) P(2) P X Development Commercial Development P(l) P(I) X P(2) X P(5) X E'(3) P(5) >one acre Heavy Industry X X X X X x Automotive X X(4)(5) X X Repair Shops Restaurants X X K X P(l) Hillside Development X K K X X K >5,000 ft2 Parking Lots P(l) P(l) K K P(l) X P(l) Retail Gasoline x x x Outlets Streets, Highways & K P(l) K X(4) X P(5) K X P(l) Freeways K = anticipated P = potential A potential pollutant if landscaping exists on-site. A potential pollutant if the project includes uncovered parking areas. A potential pollutant if land use involves food or animal waste products. Including petroleum hydrocarbons. Including solvents. LI I I I I I I Ll LI I rill LI SECTION 2: IDENTIFY POLLUTANTS, BMP SIZING AND SELECTION TABLE 2-1. ANTICIPATED AND POTENTIAL Pollutants Generated b' Land Use Tve. I LI I 23 City of Carlsbad SUSMP - January 14, 2011 I I E] I I I I I I I I I I I I I I I I I RIOW R 9* ot 7* 93W 92W a c 3° p SE 9 P 7E PE 9' 0 W: ky Choi BERNAR 14 2 ' _____ j% RA IIX,EMOUM1 S01.00 SAN i HYDROLOGIC UNIT 1108-00 PUES1.0 SAN DIEGO HY600LOGIC UNIT 90110 lagunaHA 90810 Point Lame HA " ,'J•.- - o '•4_.J%i )?,.r l r ' 111 SanJoaquinHifls NSA 908.20'.San DiegoMesaI3A - up's 4 ' 4" 1 - ( 4_\j ,_.IrJ=LJL_49 Pa1mSr,p,o.p ' t.tac Garnet .ftd 4 -M-ø N U M E N T I TR i.1.1 L iHSA .-• •a - L es9 13$ :• -; .W.t Ia Ranc ..,i IN FIVU 1 14 Dana Point NSA 90830 NatIonal City HA l * - '- ON AP L I I ONJ 'IND. ES 901 20 Mission Viejo HA 831 LI Toyan NSA - o WU.WINESS -30 1.21' Oso NSA 8.32 Paradise NSA 'I a4I MORI , SAN JACINTO - • 0 '- ( ' I .i J 122 UpperT:abucoHSA - 4 SA(EA 7 O.A- a9NAsco1.IH - IC 1.23 Middle Trabuco NSA 90900 SWEETWATER HYDROLOGIC UNIT 9 ,. q, ji ,'tri- 4 J... ' 1385 I - r.\) Ioun.1t S c - - - } '')"\ r WLOtRNLS i4j_i ..s - '. 1.24 Gobemadora NSA 90910 Lower Sweetwater HA 7- .-'-'c. .- L r; \. .' El / AC I .. ---------, •• - - - - Ii I4ci S p1 - I Oilman not 5png j '\ 1Wi?, 4ndc4Z ' \ lJ 1' - jf' I 1 PR -..iiarr.ii 4' • 'i uji(Pa / --. j j ) 1.26 JUpper San'Juen NSA Tategir ph NSA cc J,WO 20. TAS 1;2-7 Lo%ker San Juan HSA' 906i. Middle S~vntwater:HA C% V.V, Vp 9.21 Jambcha'HSA %'4k 9.22 10 10 0 es 901 San Clemente HA fe 923 DehesaHSA IA,adtov I LAKEVJEWMO NTMNSI 1 - '_j 132 SegundaDeshechaHSA 924 GaUoway NSA - - ---+--- ---- - • - - - I 1 . i Coth.MjCl Mateo Canyon HA 9.25 Sequan NSA' 901-.40 San. San Onofte I-TA 4r TA IFi San. )nokeVafleyHSA 90930 UpperSweetwatecHA - / 1- 1,uI 'k _R I, -.L.- 8A26°, I r Bum Dv . \ 1.52 "s Pulgas NSA 9.31 Loveland- kSA £4200 SANTA MARGARITA HYDROLOGIC UNIT 924 Descanso 1 a TOO &ccodL ,P ' d '5 1 ) a- p • 7546 .hó 4IA -I 2',' - ii I •23 •-.- \ \ 9.10 Gainst NSA A: 77 Mali, frimv~.. hub PAN 910.00 0TA'y 9YONLMIC: UNIT k:orona4o HA 10 MOLUMAIN Sa4age "SA Wig 5 10 - 4. fot 1 A - - bf .. • I k / be m t - 1 'T - -' : 44 1~01t emu fAtirdelia NSA 44 _14 2.35 TWAIjA HYDROLOGIC UNIT SM Dtwnond NSA RI Atild -Is? 902.40 '14A 16: 11.12 Water Tarsk: KA Ai LicalofaHSA it22 .'"4=_HSA 'S :.. 4. -- - ,. •J '• : l.," ' I' ': - e 40 44 90250 Pechang HA 11.23 Barrett NSA • I '- 2 I / A • / 1 MakU? . 4, I -J - - NTA ROSA tNDII4-9ES I I '..._ 4.... r - 2.51 PaUba NSA 1.2 Round Potr NSA I -Man I '.. 1501MW 1 / '1. - - O V - - T '-" 7 4' ---a I - .l '1 111.25 10 P 252 Lewis NSA 91140 Monument HA * , ,_ r a - - %tt j"\ .' 08 ' '."- - / / , 70- Backs-HA -902i6 tote y4l Y Coafi4iia Wig- -M HA.. 00 44 /. ` 7M-151400 01114TY Tute Creek HSA' .0 HSA 15, 1.1o" Nill NSA 11,.85 ~Hoss NSA 90290 OakgroveHA ___________________ an.plre J FE Dt..ToN' I F 4 -' c '- .,__pc! ( ' INDIANRESERVTIOI I 291 Luwea Culu rSc 1 - a .. %- I -: _.' L .c 1çi- Fol rook \ < , / i ' s... r . I ' I - ' "." -- 4 - - - 'R 910 2.91. Dodge NSA gRVAT 2.94 Chilluahub NSA T COYOTE MOUNTAW .0v A. INC Z C MW EST so SAN+ LUIS WHYDROLOGIC UNIT' MCAS J: 311 Msskin NSA Series. ( - H ydroto g I c Area Boundary (HA) ;-( (', J 0' a P 1 ' ('CD A U M A - . icor sa aaowJ ?ApL *fr* I \ #p - Uka Somali NSA. 2, A rho numbodins NA 6S col ed~ AY 314 Valley Center NSA 130 SerIes. 1 \ Woods NSA . c-LJf MT 12 T ' I ; '71I ii !J,jJsp . Ra,'ch• j' j ' V' 1 z eufa a . X. 3. MUM 16 isloto 3.22 Paul" NSA oL y*& A a S-4 not Corrft NSA 3.32 P 90400 CAfiLSeAD HYDROLOGIC UNIT OCEANSIDE ( ( at - - \I1L'11 MA. 4 II pe 4 1 •1' 90420 BuenaVistaCteekHA - / " . " \ I JI I. h52 ) L_ TIA c:7 - F-- -- - - -- - -I 4.2.1 El Salto NSA: $outh Oceans e 1 4 - hold 'Yi )? t M I ' . l - - lc, " 1' 4.22 visia NSA 9M.30. Agua HedioiWa HA AXE Ock 4.32 Buent NSA vin Lake 004.50 San maicos, R, A 51 00 4.52 4.53 .. Twin- Oaks NSA S S •S 5 5 5 .: .. .. S S5• .5. S S S S.; •-4'.• . "i" •. • C ._'° £ r-- .+-d ' -- . . ie - A E PAR ' I t* S S 90460 Escondldo Creak HA _l - '- \s " s '5' I t - I • / 1 . - 1.sAI.. I 461 San Eo NSA 4.62 FaciDindido, NSA 90500 SAN DIEGUITO HYDROLOGIC UNIT is 14 NATION Pipe Hill' • V I 905.10 Sotane8eachHA ••. •.. . .5 5 ... .• .•. .. :L.. .. .. . . . I . . S '' r / •1 '/I 4 1 ? REST.. 1tts . ____-..-____•____p. ..S f 5.11 Rancho Santa Fe 149* 1 ': / L ... -' - -... 'c.a& -a- 512 LaJo8a NSA I - - I a mard L .foiic lIlT 1I IW ,f5NL - 11 I ss ei.itv.n.y 90610 'LA Api 1- 1973 Del Di0i HS; q S. •. .: . :. + OSo S .HE.:.. .S. 5..Rov$:uty97s..:..:.. ..:.SS .: . .5 S. - •. ...Sonc .: : .. - . .- - -. • :. - z • .- .T: •-,5 r .. 5, Gresn'14SA 22 low . 5.23.' Folteita NSA 00, OAR rep 905-36 San PasquA HA 0 5431 t% h1and 14SA Piz Z.112 Us NSA 533 ReedHSA 9 07 4 I If 8 c- - 3.. - \ , __•4'_• 'las ESCRT.STAT PA 535 GuejitoflSA l R,g!onat Water Quolity Control Board- San Diego Region 9 a) ;.st:e k 9.'. -• & '4 -o 1 .t.. I II I 1? 7-e'i'r,tj I / ie L. '' J, -'. ' $36 Vineyard NSA Water Quality Stajdørda Unit 10 I • I - - 'l' - p GRA 0s_.'11 i L._ UQACAf RANCO,L,I -y ' L-.- -- - 4!f.ri I u 1g - nuts Vaish Hollow NSA - 544 Upper Natfietli NSA S.46 rose NSA 905:50 West SanteteresaHSA, . .. .. S •.• S anta Ysabef HA . . ..: . . I .•• . ' . S SS .. . . . . -- -- -- c.1a"1 - 7 ..- °-" . &-VA '4.i 1MIuIo.pEj"rk 641 0606n NSA a or N 5.53 Sutherland NSA 0~, glad Witch Cfe 5.54 ek NSA R E %#AL WAT E R QUALIT. Y CON ROL m u N I'"es Mum I int CA 906.00 11 pEtIASCIUITOS HYDROLOGIC UNIT 906.10 906.20 P6way HA IL imA AAM a n. g 0. i I -,L,. yon t e. Re o n Mitarnar HA lei 90650 Tecolote HA - - • arnacPia ' aJeAp7:hel ", ' ' -, ! ç), Missi~irt 's Disgo NSA fllI 1' I Do Cbezas"0, _L -" ASS JJ Lower San Diego HA tb I tv At 907.10 -4 ,907.00 SAN DIEGO HYDROLOGIC UMT N D t IS U- -,H Y D ROL 0 G tO BAS I N RLA -N N .1 N U-'. A K t A t'Z:W1. S A 712 San NSA us rv'. r ,MJCIIft * ' raw .' - C.' 'r - _ i t'S.. I MY YULE El C*n 5 09 00 0 7J4. Caches 14SA to; 20 Miles Wad Ed Dam POS IRA ... 7.21 :rernumux NSA .110 907 30 LI Bon I - ,o_ lDO d.cI ( P Z E En _3. £ 3 j c £ , ,..° ' Ir I I £ 7.31 Condjos Creek NSA 7.32 Glen Oaks NSA Canyon.. JA city. Raimb.t. RADIO ST to 743 Cuyama 44 c .42 Spenc a HSA . Ofl fmpai 5 - £0 ,'.Tt I . -•j 2 STA.*ol '342' I C C, 3 CD - - - - - - - - - - - - - - - - - - 2006 CWA SECTION 303(d) LIST OF WATER QUALITY LIMITED SEGMENTS REQUIRING TMDLS SAN UIECO REGIONAl. NVATI-Al Qt:AlIlV ('ONTROI. BOARD ;'•''i\ \ i\t ('AtWATER POTENTIAL ES'll\IA'I'EI) I'ROI'OSLI) TMI)L RE(;loN 'i'Vi'F NANIE \VAIl;Rslil;D POLlUTANT/SI' RISSOR SOURCES sii.i: AFFECTED COMPLETION 9 K Agua lledioiida Creek 9(14310(10 Manganese 7 Miles 2019 Source Unknown Selenium 7 Miles 2019 Source Unknown Sulfates 7 Miles 21119 Source Unknown Total Dissolved Solids 7 Miles 2019 Urban Runoff/Storm Sewers Unknown Noiipoinit Source Unknown point source 9 E Agua l-Iedionda Lagoon 90431000 Indicator bacteria 6.5 Acres 21)1)6 onpointJI'oint Source Sedi me IllS 110 n/Siltation (iii Acres 2019 Notipoint/Point Source 9 R Aliso Creek 91)1 13000 Indicator bacteria 19 Miles 2005 This lisoni,' /n,- indicator bacteria applies to the i//lit Creek ,00insie,n and all the motor irihi,h,ri 's of-i lint Creek it Inch at-c .u/phiir Creek. hood Can-von. .4/iso I/ills (anion, l)ai,- Fork, and English ('an von. Urban Runoff/Storm Sewers U uknow it point source Nonpoin)/I'oiiit Source Phosphorus 19 \ I iles 2019 /Ill, lair lot' phosphorus iij,phes ii, the list, ( lee/i uiai,istc,n and all i/ic major oil',,, n-c "i l's', ( 'is'eA ti/i/c/i are nlj'list C r,'el,. oil I aitisiti, rh/tOt [li//s mmm.luiri l-'o,'k, and Litglisli ('atom,. I rha it Kit nb ff/Sto rn Sewers Uriknipwii \on1itiiiil Siiilu'cc n know it pot r,r iiiu rce 1'i,' I a/'27 1 L i I Li I I I I I I I I I I I I [1 - - - - - - -/ - - - - - - - - - - Table 2-3. BENEFICIAL USES OF COASTAL WATERS Coastal Waters Hydrologic Unit Basin Number BENEFICIAL USE ID v R E C 1 R E C 2 C 0 M M B I 0 L T W I L 0 R A R E R A Q U A M I G R S P W N W A R M S L L Pacific Ocean S • • S S S • • 5 5 • • Dana Point Harbor • • S • S S S S S • 5 Del Mar Boat Basin S • • S • • S • • S Mission Bay 0 S S S • S • S • • 46 Oceanside Harbor S S S S • S • • S • S San Diego Bay 13 • • • • • • • • • • • • Coastal Lagoons Tijuana River Estuary 11.11 5 S • S S S • • • • Mouth of San Diego River 7.11 • • • • • • S S • 40 Famosa Slough and Channel 7.11 • S S S S S • S S 10 Los Penasquitos Lagoon 2 6.10 S S • S S • S • • S San Dieguito Lagoon 5.11 • • • S • • • • • Batiquitos Lagoon 4.51 • S • • • • • • S San Elijo Lagoon 4.61 • S • • S • S • 1 • Agua Hedionda Lagoon 4.31 5 5 5 • S • S S • S • —t-16 Includes the tidal prisms of the Otay and Sweetwater Rivers. Fishing from shore or boat permitted, but other water contact recreational (REC- 1) uses are prohibited. The Shelter Island Yacht Basin portion of San Diego Bay is designated as an impaired water body for dissolved copper pursuant to Cle a n W a t e r A c t section 303id). A Total Maximum Daily Load (TMDL) has been adopted to address this impairment. See Chapter 3, Water Quality Objectives for Pesticides, Toxicity and Toxic Pollutants and Chapter 4, Total Maximum Daily Loads. S Existing Beneficial Use bENEi-ii- i - MM Table 2-3. BENEFICIAL USES OF COASTAL WATERS Coastal Waters Hydrologic Unit Basin Number BENEFICIAL USE D v R E C 1 R E C 2 C 0 M M B I 0 L -r W I L D R A R E R A Q U A M I G R S P W N W A R M L L Coastal Lagoons - continued Buena Vista Lagoon 2 4.21 S S • 0 • S S S Loma Alta Slough 4.10 S • • • • • Mouth of San Luis Rey River 3.11 S S S S S S Santa Margarita Lagoon 2.11 5 5 S • S S S S Aliso Creek Mouth 1.13 5 5 5 5 S San Juan Creek Mouth 1.27 5 • S S S S - San Mateo Creek Mouth 1.40 S S S S S S S S San Onofre Creek Mouth 1.51 5 5 5 5 5 S • - - 2 Fishing from shore or boat permitted, but other water contact recreational (REC-1) uses are p r o h i b i t e d . S Existing Beneficial Use o Potential Beneficial Use TaI I ;• BENFJ LS I i I I LI I Li I LI I I I I I I I I I I - Stormwater Pollutant Sources and Source Control Checklist How to Use this Checklist: Review Column I and identify which of these potential sources of stormwater pollutants appl y t o y o u r p r o j e c t . C h e c k e a c h b o x t h a t a p p l i e s . Review Column 2 and incorporate all of the corresponding applicable BMPs in your SUSMP Dra w i n g s , Review Columns 3 and 4 and incorporate all of the corresponding applicable permanen t c o n t r o l s a n d o p e r a t i o n a l B M P s i n a t a b l e i n y o u r S U S M P D r a w i n g s . F o r PDP's, in your SWrvlP, use the format shown in Table 3-1. In the SWiv1P, describe your spec i f i c B M P s i n a n a c c o m p a n y i n g n a r r a t i v e , a n d e x p l a i n a n y s p e c i a l conditions or situations that required omitting BMPs or substituting alternatives. IF THESE SOURCES WILL BE ON THE PROJECT SITE ... THEN YOUR PROJECT SHOULD INCLUDE THESE SOURCE CONTROL BMPs 1 2 3 4 Potential Sources of Permanent Controls—Show on Permanent Controls—List in SWMP Operational BMPs—Include in Runoff Pollutants SUSMP Drawings Table and Narrative SWMP Table and Narrative A. Onsite storm drain Locations of inlets. " Mark all inlets with the words "No EI Maintain and periodically repaint or inlets Dumping! Flows to Bay" or similar, replace inlet markings. 'Provide stormwater pollution prevention information to new site owners, lessees, or operators. W-1ee applicable operational BMPs in Fact Sheet SC-44, "Drainage System Maintenance," in the CASQA Stormwater Quality Handbooks at www.cabmphandhooks.com 1k" Include the following in lease agreements: "Tenant shall not allow anyone to discharge anything to storm drains or to store or deposit materials so as to create a potential discharge to storm drains." Page 1 of 9 . . - U B. Interior floor drains U State that interior floor drains and U Inspect and maintain drains to and elevator shaft sump elevator shaft sump pumps will be prevent blockages and overflow. pumps plumbed to sanitary sewer. U C. Interior parking U State that parking garage floor drains U Inspect and maintain drains to garages will be plumbed to the sanitary sewer. prevent blockages and overflow. U Dl. Need for future U Note building design features that U Provide Integrated Pest Management indoor & structural pest discourage entry of pests. information to owners, lessees, and control operators. D2. Landscape!Sr"_ Show locations of native trees or State that final landscape plans will Maintain landscaping using Outdoor Pesticide Use areas of shrubs and ground cover to accomplish all of the following, minimum or no pesticides. be undisturbed and retained. B' Preserve existing native trees, shrubs, Sec applicable operational BMPs in Show self-retaining landscape and ground cover to the maximum Fact Sheet SC-41, "Building and areas, if any. extent possible. Grounds Maintenance," in the CASQA Stormwater Quality Y' If a PDP, show stormwater Q' Design landscaping to minimize Handbooks at treatment facilities. irrigation and runoff, to promote www.cabrnphandbooks.com surface infiltration where appropriate, and to minimize the use of fertilizers Provide IPM information to new and pesticides that can contribute to owners, lessees and operators. stormwater pollution. Where landscaped areas are used to retain or detain stormwater, specify plants that are tolerant of saturated soil conditions. ' Consider using pest-resistant plants, especially adjacent to hardscape. To insure successful establishment, select plants appropriate to site soils, slopes, climate, sun, wind, rain, land use, air movement, ecological consistency, and plant interactions. U E. Pools, spas, ponds, U Show location of water feature and U If the local municipality requires pools U See applicable operational BMPs in decorative fountains, a sanitary sewer cleanout in an to be plumbed to the sanitary sewer, Fact Sheet SC-72, "Fountain and and other water accessible area within 10 feet. place a note on the plans and state in Pool Maintenance," in the CASQA features. the narrative that this connection will Stormwater Quality Handbooks at be made according to local www.cabmphandbooks.com requirements. Page 2 of 9 - - - - - - - - - - - O F. Food service 0 For restaurants, grocery stores, and other food service operations, show location (indoors or in a covered area outdoors) of a floor sink or other area for cleaning floor mats, containers, and equipment. 0 On the drawing, show a note that this drain will be connected to a grease interceptor before discharging to the sanitary sewer. 0 Describe the location and features of the designated cleaning area. U Describe the items to be cleaned in this facility and how it has been sized to insure that the largest items can be accommodated. U U G. Refuse areas 0 Show where site refuse and U State how site refuse will be handled 0 State how the following will be recycled materials will be handled and provide supporting detail to what implemented: and stored for pickup. See city is shown on plans. standard drawing GS-16. Provide adequate number of U State that signs will be posted on or receptacles. Inspect receptacles If dumpsters or other receptacles near dumpsters with the words "Do regularly; repair or replace leaky U are outdoors, show how the not dump hazardous materials here" receptacles. Keep receptacles designated area will be covered, or similar. covered. Prohibit/prevent dumping graded, and paved to prevent run- of liquid or hazardous wastes. Post on and show locations of berms to "no hazardous materials" signs. prevent runoff from the area. Inspect and pick up litter daily and clean up spills immediately. Keep Any drains from dumpsters, spill control materials available on- E3 compactors, and tallow bin areas site. See Fact Sheet SC-34, "Waste shall be connected to a grease Handling and Disposal" in the removal device before discharge to CASQA Stormwater Quality sanitary sewer. Handbooks at www.cabniphandbooks U H. Industrial processes. 0 Show process area. U If industrial processes are to be U See Fact Sheet SC-10, "Non- located on site, state: "All process Stormwater Discharges" in the activities to be performed indoors. No CASQA Stormwater Quality processes to drain to exterior or to Handbooks at storm drain system." www.cabmphandbooks.com Page 3 of 9 — — — — — — — — low — — — — — — — U I. Outdoor storage of U Show any outdoor storage areas, U Include a detailed description of U See the Fact Sheets SC-31, "Outdoor equipment or materials, including how materials will be materials to be stored, storage areas, Liquid Container Storage" and SC- (Sec rows J and K for covered. Show how areas will be and structural features to prevent 33, "Outdoor Storage of Raw source control graded and bermed to prevent run- pollutants from entering storm drains. Materials "in the CASQA measures for vehicle on or run-off from area. Stormwater Quality Handbooks at cleaning, repair, and Where appropriate, reference www.cabniphandbooks.com maintenance.) U Storage of non-hazardous liquids documentation of compliance with the shall be covered by a roof and/or requirements of local Hazardous drain to the sanitary sewer system, Materials Programs for: and be contained by berms, dikes, liners, or vaults. Hazardous Waste Generation U Storage of hazardous materials and Hazardous Materials Release wastes must be in compliance with Response and Inventory the local hazardous materials ordinance and a Hazardous California Accidental Release Materials Management Plan for the (Ca.IARP) site. Aboveground Storage Tank Uniform Fire Code Article 80 Section 103(b) & (c) 1991 Underground Storage Tank Page 4 of 9 U J. Vehicle and U Show on drawings as appropriate: U If a car wash area is not provided, Describe operational measures to Equipment Cleaning describe measures taken to discourage implement the following (if Commercial/industrial facilities on-site car washing and explain how applicable): having vehicle /equipment these will be enforced. cleaning needs shall either provide U Washwatcr from vehicle and a covered, bermed area for washing equipment washing operations shall activities or discourage not be discharged to the storm drain vehicle/equipment washing by system. removing hose bibs and installing signs prohibiting such uses. U Car dealerships and similar may rinse cars with water only. Multi-dwelling complexes shall have a paved, bermed, and covered U See Fact Sheet SC-21, "Vehicle and car wash area (unless car washing Equipment Cleaning," in the CASQA is prohibited on-site and hoses are Stormwater Quality Handbooks at provided with an automatic shut- www.cabniphandbooks.com off to discourage such use). Washing areas for cars, vehicles, - and equipment shall be paved, designed to prevent run-on to or runoff from the area, and plumbed to drain to the sanitary sewer. Commercial car wash facilities shall be designed such that no runoff from the facility is discharged to the storm drain system. Wastewater from the facility shall discharge to the sanitary sewer, or a wastewater reclamation system shall be installed. Page 5 of 9 - - - - - - - - - - - - - - - _1Th_ - U K. Vehicle /Equipment U Accommodate all vehicle U State that no vehicle repair or In the SUSMP report, note that all of Repair and equipment repair and maintenance maintenance will be done outdoors, or the following restrictions apply to use Maintenance indoors. Or designate an outdoor else describe the required features of the site: work area and design the area to the outdoor work area. prevent run-on and runoff of U No person shall dispose of, nor stormwater. U State that there are no floor drains or if permit the disposal, directly or there are floor drains, note the agency indirectly of vehicle fluids, hazardous U Show secondary containment for from which an industrial waste materials, or rinsewater from parts exterior work areas where motor discharge permit will be obtained and cleaning into storm drains. oil, brake fluid, gasoline, diesel that the design meets that agency's fuel, radiator fluid, acid-containing requirements. No vehicle fluid removal shall be batteries or other hazardous performed outside a building, nor on materials or hazardous wastes are U State that there are no tanks, U asphalt or ground surfaces, whether used or stored. Drains shall not be containers or sinks to be used for parts inside or outside a building, except installed within the secondary cleaning or rinsing or, if there are, note in such a manner as to ensure that containment areas. the agency from which an industrial any spilled fluid will be in an area of waste discharge permit will be secondary containment. Leaking U Add a note on the plans that states obtained and that the design meets vehicle fluids shall be contained or either (1) there are no floor drains, that agency's requirements. drained from the vehicle or (2) floor drains are connected to immediately. wastewater pretreatment systems prior to discharge to the sanitary No person shall leave unattended sewer and an industrial waste drip parts or other open containers discharge permit will be obtained. Cl containing vehicle fluid, unless such containers are in use or in an area of secondary containment. Page 6 of 9 - _\ - - - - - - - (_ - - - - - - .Th - - I] L. Fuel Dispensing U Fueling areas' shall have U The property owner shall dry sweep Areas impermeable floors (i.e., portland the fueling area routinely. cement concrete or equivalent smooth impervious surface) that U See the Business Guide Sheet, are: a) graded at the minimum "Automotive Service—Service slope necessary to prevent ponding; Stations" in the CASQA Stormwater and b) separated from the rest of Quality Handbooks at the site by a grade break that www.cabmphandbooks.com prevents run-on of stormwater to the maximum extent practicable. Fueling areas shall be covered by a canopy that extends a minimum of U ten feet in each direction from each pump. [Alternative: The fueling area must be covered and the cover's minimum dimensions must be equal to or greater than the area within the grade break or fuel dispensing areal.] The canopy [or cover] shall not drain onto the fueling area. The fueling area shall be defined as the area extending a minimum of 6.5 feet from the corner of each fuel dispenser or the length at which the hose and nozzle assembly maybe operated pl u s a m i n i m u m o f o n e foot, whichever is greater. Page 7 of 9 - - - - - - - - M - - - - - - \_ - U M. Loading Docks U Show a preliminary design for the U Move loaded and unloaded items loading dock area, including indoors as soon as possible. roofing and drainage. Loading docks shall be covered and/or U See Fact Sheet SC-30, "Outdoor graded to minimize run-on to and Loading and Unloading," in the runoff from the loading area. Roof CASQA Stormwater Quality downspouts shall be positioned to Handbooks at direct stormwater away from the www.cabrnphandbooks.com loading area. Water from loading dock areas should be drained to the sanitary sewer where feasible. Direct connections to storm drains from depressed loading docks are prohibited. U Loading dock areas draining directly to the sanitary sewer shall be equipped with a spill control valve or equivalent device, which shall be kept closed during periods of operation. Provide a roof overhang over the U loading area or install door skirts (cowling) at each bay that enclose the end of the trailer. U N. Fire Sprinkler Test U Provide a means to drain fire sprinkler U See the note in Fact Sheet SC-41, Water test water to the sanitary sewer. "Building and Grounds Maintenance," in the CASQA Stormwater Quality Handbooks at www.cabrnphandbooks.com Page 8 of 9 0. Miscellaneous Drain 0 Boiler drain lines shall be directly or or Wash Water indirectly connected to the sanitary sewer system and may not discharge 3 Boiler drain lines to the storm drain system. Condensate drain lines U Condensate drain lines may discharge to landscaped areas if the flow is small Rooftop equipment enough that runoff will not occur. Condensate drain lines may not ci Drainage sumps discharge to the storm drain system. 3 Roofing, gutters, and Rooftop mounted equipment with trim, potential to produce pollutants shall be roofed and/or have secondary containment. Any drainage sumps on-site shall feature a sediment sump to reduce the quantity of sediment in pumped water. Avoid roofing, gutters, and trim made of copper or other unprotected metals that may leach into runoff. Plazas, sidewalks, LW Plazas, sidewalks, and parking lots and parking lots, shall be swept regularly to prevent the accumulation of litter and debris. Debris from pressure washing shall be collected to prevent entry into the storm drain system. Washwater containing any cleaning agent or degreaser shall be collected and discharged to the sanitary sewer and not discharged to a storm drain. Page 9 of 9 I I P I I I Li I I I I Li H I H 1 I I I I I I I I I I I I I I I I 1 1 I I I SECTION 2: IDENTIFY POLLUTANTS, BMP SIZING A N D S E L E C T I O N ' Go to N Figure 2.4 '\ of the Decision / Matrix 1. Project using '. SCCWRP Screening Tools? ..- >- ' Do BMPs Include Infiltration To Native Soils'? E. __- 3. Has 13eotech Conlimed 4. Size LID and BMP Facilities for Flow Range of 0.10to 0 , i!( Draw down Time Requirements End of Decision Matrix Consult with Geotechnical Enaineer LID or BMP FIG URF 2-2. Mitic)WrJoil Criteria and Implementation I 38 City of Carlsbad SUSMP - January 14, 2011 LABILE BED Sand- Dominated d <16mm 4 Surface Sand : 25% 'thosely. Packed INTERMEDIATE BED 'Moderatelyto Loosely- Packed Cobble I Gravel Hardpan of Uncertain Depth, E'tent&odibllity I I I I I I I I I) I I I I I I I I COARSEIARMORED BED > 128 mm 'Boulder/Large Cobble 'Tightly. Poked (5 Sand .Continuous Bedrock.. Contmuous Concrete HIGH I EPMINE RISK FACTORS I 'Grade Control Amoring Potential 4 Proximnyto Incision Threshold 'Go to Dote Bed &odibility Figure 1 2.6 j Checklists and Incision Diagram Checklist Fill out SCCWRP Scoring Ciitria to Determine if the RecenAig Channel has a HIGH, MEDIUM or LOW Susceptibility, 1011 J 1MEDIUM1 SECTION 2: IDENTIFY POLLUTANTS, BMP SIZING AND SELECTION Figure 2.2 I CHANNEL BED RESISTANCE I Dote Figure 2.5 SIW"\ V)('M(JE kt'J11 kFM' Go to Figure 2.5 FIGURE 2-4. SCC\XJRP Vertical Susceptibility Matrix 44 City of Carlsbad SUSMP - January 14, 2011 SECTION 2: IDENTIFY POLLUTANTS, BMP SIZING AND SELECTION Figure 2.4 LOW krrored / Bedrock Bank tabdizrin Good Condition iio LATERALLY ADJUSTABLE? formation I Avulsions: )EI .Fufly Con Mass Wasting orAre ned DtY Lateral Fluvial Coreetedto'HiHstde.Vl-1 ,ustrnerits Extensive os ion or Chut Culofffmrizion ED HIGH i(2 VUVI) None orElusial Only IJmitedto 7 GOtO "\ 8endsacidonstnctions UM;Inx~' Et 7'ftI Bank Strata Moderat$yor Well- Consolidated Consolidated }-04 Poorly or Unconsolidated I inudin9 Toe? ,j Bank Height Bank Height Coarse I Fine Fine (10% Logistic >10% Logistic Resistant Toe, Unconsolidated Unconsolidated I Risk for Angle Riskforhgle .064mrn . ,ANDW/I2 ANDV$II>2 AND ml> 2 4, HIGH GH PFFigurme ) 43 0, Braiding Braiding Risk)50% Risk o LOW LOW MED HIGH Braiding 2 ,JGH2 eiiirg 1E2 . Braiding Braiding fisk ( 60% Risk 60%, Risk <D% Risk >. SOt Go to Figure 2.3 ~ollh Matrix Matrix A UD FIGURE 2-5. Lateral Channel Susceptibility Matrix &J't'J kw Er 13 45 City of Carlsbad SUSMP - January 14, 2011 I I I I I 1 I I I I I I I I I I I I I C, 3 CD 0 DRAINAGE MANAGEMENT AREA SUMMARY DM ~]AREA A ('A C) PRE-PROJECT Co VER POST SURFACE TYPE SOIL TYPE EXIST SLOPE BIVP ID DMA Al-1 0.16 IMPERVIOUS Concrete or asphalt D Flat BMP1 Flat DMA A1-2 0.02 PERVIOUS Landscaping D Steep DMA A1-3 0.1 PERVIOUS Concrete or asphalt D Flat DMA A1-4 0.02 IMPERVIOUS Pervious concrete D DMA A2-1 0.56 IMPERVIOUS Concrete or asphalt D Flat DMA A2-2 0.07 PERVIOUS Landscaping D Flat BMP2 DMA A2-3 0.46 PERVIOUS Concrete or asphalt D Steep DMA A2-4 0.3 IMPERVIOUS Pervious concrete D Flat DMA 131-1 0.1 IMPERVIOUS Concrete or asphalt D Flat .. .. BMP10 Flat DMA 61-2 0.01 PERVIOUS Landscaping D Steep DMA 131-3 0.08 PERVIOUS Concrete or asphalt D Steep DMA 131-4 0.05 IMPERVIOUS Pervious concrete D DMA 132-1 0.12 IMPERVIOUS Concrete Or asphalt. D Flat .--..-.... BM.P9 Flat DMA 132-2 0.03 . Steep DMA B2-3 0.07 PERVIOUS . PERVIOUS .......Landscaping..............D Concrete or asphalt D Flat DMA B2-4 0.03 IMPERVIOUS Pervious concrete D DMA B3-1 0.04 IMPERVIOUS Concrete or asphalt D Steep BMP8 Flat DMA 63-2 0.02 PERVIOUS ILandscaping D Steep DMA 133-3 0.03 PERVIOUS Concrete or asphalt D Flat DMA 133-4 0.03 IMPERVIOUS Pervious concrete D DMA 134-1 0.09 IMPERVIOUS Concrete or asphalt D Steep DMA 134-2 0.05 PERVIOUS Landscaping D Steep BMP7 DMA 134-3 0.06 PERVIOUS Concrete or asphalt D Flat DMA 134-4 0.06 IMPERVIOUS Pervious concrete D Flat DMA 135-1 0.07 IMPERVIOUS Concrete or asphalt D Steep DMA 135-2 0.02 PERVIOUS Landscaping D Steep BMP6 Flat DMA 135-3 0.03 PERVIOUS Concrete or asphalt D Flat DMA 135-4 0.03 IMPERVIOUS Pervious concrete D DMA 136-1 0.03 IMPERVIOUS Concrete or asphalt D Steep BMPS Flat DMA 136-2 0.06 PERVIOUS Concrete or asphalt D Flat DMA 136-3 0.03 IMPERVIOUS Pervious concrete D DMA 137-1 0.06 IMPERVIOUS Concrete or asphalt D . Flat B1v1P4 Flat DMA 137-2 0.01 PERVIOUS Landscaping D Steep DMA 137-3 0.06 PERVIOUS Concrete or asphalt . D Steep DMA 137-4 0.03 IMPERVIOUS Pervious concrete D DMA 138-1 0.06 IMPERVIOUS Concrete or asphalt D Flat BMP3 DMA 138-2 0.02 PERVIOUS Landscaping D Steep DMA 138-3 0.03 PERVIOUS Concrete or asphalt D Steep DMA 138-4 0.03 IMPERVIOUS Pervious concrete D Flat. DMA C-i 0.5 IMPERVIOUS Concrete or asphalt D Flat . BMP11. DMA C-2 0.83 PERVIOUS Landscaping D Steep DMA C-3 0.29 PERVIOUS Concrete or asphalt D Moderate DMA D-i 0.08 IMPERVIOUS Concrete or asphalt D Flat BMP12 DMA D-2 0.01 . PERVIOUS Landscaping .. D Steep DMA D-3 0.07 PERVIOUS concrete or asphalt D Steep DMA D-4 0.01 IMPERVIOUS . Pervious concrete D Flat DMA E-1 0.12 IMPERVIOUS Concrete or asphalt D Flat BMP13 Flat DMA E-2 0.04 PERVIOUS . Landscaping D Steep DMA E-3 0.17 PERVIOUS Concrete or asphalt D Steep DMA E-4 0.05 IMPERVIOUS Pervious concrete D DMA F-i 0.2 IMPERVIOUS Concrete or asphalt D Flat N/A ... ..... Flat DMA F-2 0.01 PERVIOUS Landscaping D Steep DMA F-3 0.13 PERVIOUS . Concrete or asphalt D Steep DMA F-4 0.13 IMPERVIOUS Pervious concrete D DMA G1-1 0.19 . IMPERVIOUS Concrete or asphalt D . Flat BMP17 Flat DMA G1-2 0.03 PERVIOUS Landscaping D Steep DMA G1-3 0.1 PERVIOUS Concrete or asphalt D Steep DMA G1-4 0.06 IMPERVIOUS Pervious concrete D DMA G2-1 0.16 IMPERVIOUS Concrete or asphalt D Flat BM.P16 DMA G2-2 0.02 PERVIOUS Landscaping. D Steep DMA G2-3 0.1 PERVIOUS Concrete or asphalt D Steep DMA G2-4 0.06 IMPERVIOUS Pervious concrete D Flat DMA G3-1 0.17 IMPERVIOUS Concrete or asphalt D Flat DMA G3-2 0.02 PERVIOUS Landscaping D Steep DMA G3-3 0.09 PERVIOUS Concrete or asphalt D Steep DMA G3-4 0.09 IMPERVIOUS Pervious concrete D Flat DMA G4-1 0.38 IMPERVIOUS Concrete or asphalt 0 Flat .............. DMA G4-2 0.02 PERVIOUS Landscaping D Steep BIV!.14 Flat DMA G4-3 0.14 PERVIOUS Concrete or asphalt D Steep DMA G4-4 0.23 IMPERVIOUS Pervious concrete D DMA HI-1 0.42 IMPERVIOUS Concrete or asphalt D Flat BM.!...8 DMA 1-11-2 0.58 PERVIOUS Landscaping D Steep DMA Hi-3 0.36 PERVIOUS Concrete or asphalt D Steep - DMA 1-11-4 0.2 IMPERVIOUS Pervious 'concrete D Flat DMA 1-12-1 0.42 IMPERVIOUS Concrete or asphalt D . Flat BMP1. Steep DMA 1-12-2 0.46 PERVIOUS Landscaping D Steep DMA 1-12-3 0.3 PERVIOUS Concrete or asphalt D DMA H3-1 0.21 IMPERVIOUS Concrete or asphalt D Flat BM?20 . Moderate DMA 1-13-2 0.08 PERVIOUS Landscaping D Flat DMA H3-3 0.1 PERVIOUS Concrete or asphalt D DMA I-i 0.51 IMPERVIOUS Concrete or asphalt D Flat DMA 1-2 0.17 PERVIOUS Landscaping D Flat BfP2,1 Flat DMA 1-3 0.37 PERVIOUS Concrete or asphalt D Flat DMA 1-4 0.08 IMPERVIOUS Pervious concrete D DMA il-i 0.44 IMPERVIOUS Concrete or asphalt D Flat DMA J1-2 0.06 . PERVIOUS Landscaping D Flat S BI... DMA J1-3 0.15 PERVIOUS Concrete or asphalt D Flat DMA J1-4 0.05 IMPERVIOUS . Pervious concrete D Flat DMA i2-1 0.05 IMPERVIOUS Concrete or asphalt D Flat BMP22 .-.... Flat DMA J2-2 0.02 PERVIOUS Landscaping D Flat DMA J2-3 0.06 PERVIOUS Concrete or asphalt D Flat DMA J2-4 1 0.03 IMPERVIOUS Pervious concrete . D IMP (TOMPIH YDROA MON liON/LID) FA C/I/fl' SUMMARY BMP ID / TYPE BIORETENTION AREA REQUIRED VOLUME 1 REQUIRED VOLUME 2 REWIRED ORIFICE., FLOW ORIFICE SIZE 1. FL OW- THROUGH PLANTER 305 SF 254 CF 183 CF a 06 CFS 1.0 INCH 2 FLOW- THROUGH PLANTER 1268 SF 1057 CF 761 CF a JO CFS JO INCH 3 FLOW- THROUGH PLANTER 87 SF 73 CF 52 CF a. 03 CFS 0.9 INCH 4 FL OW- THROUGH PLANTER . 162 SF 135 CF 97 cr a OJ crs 0.9 INC/-I 5 FL OW- THROUGH PLANTER 172 SF 143 CF 103 CF a OJ CFS a 8 INCH 6 FLOW- THROUGH PLANTER 88 SF 73 CF 53 CF a 03 CFS a 9 INCH 7 FLOW- THROUGH PLANTER 174 SF 145 CF 104 CF a 06 CFS 1.0 INCH 8 FLOW- THROUGH PLANTER 85 SF 71 CF 51 cr a 03 CFS a 8 INCH 9 FLOW-THROUGH PLANTER 197 SF 164 CF 118 CF a 05 Cr5 1.0 INCH 10 FLOW- THROUGH PLANTER 220 SF 183 CF 132 CF 0.05 CFS 1.0 INCH 11 FLOW-THROUGH PLANTER 970 SF 809 CF 582 CF 0.27 CFS 3.0 INCH 12 * FLOW- THROUGH PLANTER 187 SF 156 CF 112 CF a OJ CFS. 09 INCH 13 * FLOW- THROUGH PLANTER 446 SF 372 CF 268 CF a 06 CFS 1.0 INCH 14 FLOW-THROUGH PLANTER 407 SF 339 CF 244 CF 019 CFS 2.0 INCH 15 FLOW-THROUGH PLANTER 256 SF 213 CF 154 CF a 09 CFS 20 INCH 16 FLOW- THROUGH PLANTER 279 SF 233 CF 167 CF - 0. 08 CFS'.-."r ..,. 1.0 INCH.. 17 *• FLOW- THROUGH PLANTER . -. 299 SF 249 CE 179 CF . a 07 CFS 1.0 INCH 18 FLOW- THROUGH PLANTER 1063 SF 886 CF 638 CF 0. JO CFS 3.0 INCH 19 FLOW-THROUGH PLANTER 860 SF 717 CF 516 CF . 021 CFS . 20INCH 20 FLOW- THROUGHPLANTER 329SF 274CF . 197 CF a 08 CFS 1.0INCH 21 FLOW- THROUGH PL A N TER 1180SF 982CF 708CF 0.21CFS 20INCH 22, FLOW- THROUGH PLANTER 189SF 157CF . 11J CF 0.03 CFS- 09INCH 23 FLOW- THROUGHPLANTER 475SF L L;;6CF 285CF 016CF5 20INCH 4" MIN. DEPTH AT NARROW MEDIAN PROVIDED EN11RE VOLUME AS V2. SEE SUPPLEMENTAL CAL CULA liONS IN A TTACHMENT /12 CURB Off N/NC DA TA TABLE ID STA. 0 ' MOD. D-02 WIDTH OF OPEMNC 1 446-i-60 4.00' 2 446+90 780' 3 454+35 280' 4 455+29 280' 5 456+00 280' 6 456+70 3.50' 7 457+40 3.50' 8 458+80 3.50' 9 459*50 3.50' 10 460+30 3.50' 10 461+15 3.50' 11 455+32 16 11.60' 12 462+88 3.50' 13 465+ 00 5.80' 13 466+09.63 . 5.80' 14 . 476+35 11.34' 15 479+20 5.80' 16 480+60 5.80' 17 482+85.04 3" 18 473-i- 15 5.30' 18 474+30 5.30' 19 480+80 6.20' 20 482+ 15 6.20' 21 484+60 14.06' 22 . 489+70 6.10' 23 490+35 . 19.40' MOD. D-27 4" PIPE PER SDRSD SINGLE SHEET BAIP EXHIBIT FOR EL CA VINO REAL WIDENING ESS co NO. 32014 EXP. 12/31/14 J G:\101307\SWMP\ECR-Widening\P-SubmttaI 2\W-ATTACHMErJT10-02.dwg Feb 25, 2014 8:16am Xrefs: .. .. ......... - ..-..-....--.--... ...........-.--..... .... ............---- . •.---. _____.._____ ........- •: ..........7............................••__ .._................................I . ___..... . -- I I OWE/TACK DOWN LINER JLS 36" MIN WIDTH VAR/ES PER PLAN 240 MIN* BIORETENT/ON AREA . Pz 14-1 1.0' Mliv. MANHoLe PER 18" SAND/COMPOST MIX . (SDRSD 41-2 zR 5C,33 IN 1 HR INFILTRATION •. RATE TO BE VERIFIED BY . cm CIO 12" CEOTECHMCAL ENGINEER MIN I INSTALL RIP RAP / I AT ___ I - '_ VARIES I , I _________ __________________ __________ IMPERMEABLE LINER - TO BE VERIFIED BY A _________ PER CEO ____________ Co 1O"MIN 20'MAXI .4 I ___________ / ,.. . . / ..- / ' * 1" I . / / / / c - __________ (4 Mliv '' MAX*vir- - 12 1 'iNSTALL MONOLi I . _,:...1-, ..." . . , , . . . \'_ -- / / / /1. - - / COTTER 'AT D25 -, -"1 (J l . L..4 (i/i ______________ INSTALL 5 RATE - GEOTECHMCAL ENCINEER __________________ RECOMMENDATIONS - - - S \ 7 . 6" PERFORATED PVC SCIL 40 - . . .- ... .. I U flIVU/ (1IV/(JJ I IVIlA 1N/HR INFIL INFILTRATION TECHNICAL Z SEE NOTE 2 - - 411RAF1140N - - 18" PERMEABLE BASE -. -. - . - -.1 - W/401 POROSITY / .. I UNDERDRAIN WITH PERFORATIONS, " 18" OR 43" PERMEABLE BASE 7 . I POINTED DOWNWARD WRAPPED IN WITH 40% POROSITY . A SOCK OF MIRAFI FILTER FABRIC INSTALL . j // / \`, I.- I INFL 1UPERUEABLE LINER _;0 V_ f ~ 6" PERFORATED PVC ScH 40 PROTECT PLAcE ,'i8l_~\\\ I . ' LOUTS/DE . RIGHT—OF— WA Y UNDERDRAIN WITH PERFORATIONS ,/ . . . .-•-. POINTED DOWNWARD WRAPPED IN A ,r.. , SOCK OF Al/RAFt FILTER FABRIC NOTES / 1.1 INFLUENCE I. SEE SECTION 4 OF CITY OF CARLSBAD STANDARD URBAN STORM WATER MANAGEMENT fli A Al fi ii i 1 A 4 /4 A /fl 4 4 A IA! ,i, / I . .1 BMP TABLE TREATMENT CONTROL BMP ID # BMP TYPE SYMBOL CASQA NO. QUANTITY DRAWING NO. SHEET NO.(S) INSPECTION MAINTENANCE CONSTRUCTION SIGN OFF BIORETENTION AREA L7-1-1 .- 1. 7 . SEMI-ANNUAL SEMI-ANNUAL LOW IMPACT DESIGN (LID) BMP TYPE SYMBOL CASQA NO. QUANTITY INSPECTION DRAWING NO. - SHEET NO.(S) MAINTENANCE NSTRUC11ON CO SIGN OFF PERVIOUS PAVEMENT SD-20 43725 SF 477-6 34-42 ANNUALLY TO PREVENT CLOGS SOURCE CONTROL ____________ BMP TYPE SYMBOL CASQA NO. QUANTITY DRAWING NO. SHEET NO.(S) INSPECTION MAINTENANCE CONSTRUCTION SIGN OFF - STORM DRAIN SYSTEM SIGN* E SD-13 13 EA SWMP 13-03 1 ANNUALLY VERIFY LEGIBILITY OF SIGNS SITE DESIGN & LANDSCAPE ., -. SD 10 / VEGETATIVE MANAGEMENT PLANNING, EFFICIENT - . . SD-12 SEMI-ANNUAL REPAIR BROKEN SPRINKLERS IRRIGATION ............-, .1. AS NEEDED SIDEWALK SWEEPING SEE PLAN .. SEMI-ANNUAL 1. SWEPT REGULARLY . TO PREVENT BUILDUP OF LITTER & DEBRIS \ rL/v (.)uJMrJ 11/11W 1/ I't/LVI I, ttlfI /illli/I1(JIVML LI/VIrL It/V/IL//V .)t'tL,/t/LA/IU/V.). *"NO DUMPING! FLOWS TO AGUA HEDIONDA LAGOON" STENCIL ON ALL CURB INLETS 2 IMPERMEABLE LINER SHALL BE JOAIIL PVC LINER, SPECIFIC GRAVITY (ASTM D792): I., 120 (MIN), TENSILE (ASTV D 882) 7J (WIN IDTH, MIAQ ELONGATION AT BREAK . I /VU/ U) L/ILL - (ASTM D882): 380 (Z )W/N), MODULUS (ASTM D 882): 30 (LB//N-WIDTH, U/N.), TEAR - -•- _/ -C (4STM D 1004): 30 (LB//N, U/N.). PER GEOSOILS RECOMMENDATIONS IN NOTES: -. - _____,_.77_ - -. :: : EMAIL DATED 6/17/2013. 1. SEE SDRSD D-02 FOR ADDITIONAL SPECIFICATIONS - - -. - - vl - - . - - .: I. 2 SEE SECT/ON 4 OF C/fl' OF CARLSBAD STANDARD URBAN STORM WATER MANAGEMENT 01111- - PLAN (susuP) DATED 1/14/2011, FOR ADD/17ONAL BIORETENT/ON SPECIFICATIONS . - - - 11 - - - / 3 FOR BIORETENT/ON AT 80' MED/AN 1.- : - 11 : : 4 IMPERMEABLE LINER SHALL SE 3041/L PVC LINER, SPECIfiC GRAVI1Y (ASTM 13292) .--. - - - pJ Ct!- - - 1 120 (MIN), TENSILE (ASTM 13 882) 73 ('LB/IN-kY/Dr/-I, MIN), ELONGATION AT BREAK - - - :,, uvJ 1MG, AT *80# - 11 '0 C/N 'ni° 2 (ASTM 13882) 380(ZM/N), MODULL'S(ASTMD882) JO(LB//N-WIDT//, U/ N), TEAR S -_ .. 1.-'- -7:z- CATCHDI4I. ( / i -; \ J RESISTENC((ASTMD1004).)O(LB4NM/N)PERGEOSO/LSRECOMMENDAT/ONSIN - - - 11 !11 • - -• - - 1. -- EMAIL DATED 6/17/2013 - -. r I - - - 7 :- :: ::: :1~ &_ - - — /~7 - - I )~ : : : - : : : : - •- : -:_. ,,;::-;--;-- — — - I ASIPL__ - --- ------------------I 11----------------------------- I 1.11 IT BA S/Af 141 030 AC -- • .--:- p — - •-- - -. - 2A 016 AC 11 - BAS/NA2 1J94 - -------- - . - --•- -•. - - U) - - ---- - - -1111~ - - - - ----- — I - ----- - - . - ______-S - - I. : - • : : •- : : : : - : - ...- -- SY,Y81 - 15 - - - I - z. - - - - _ - - - -' - _ : - - _ - - ---- '18/4, 26 '-• -- - - I -5....... . Qi 4 ELCAA1/NO REAL - - -:-•: : ------.... .iB2 - n 6 -'-, 3 --------------------------------.---:: -- I - '- ----. -•• - - '-••• -•- /' - -s'- - AS'gG 8 ----'--'--- ' -: :;I "I SIN - - '• -- : I : - - -• : :- .~ A IV . .. I j ~ 5:71 ~______ ,,,~"; /' -- - - - - - --s- -- - -o ii 12 - - lii i l - :: - - : - : ': : - - 4 - - I I I / .1 ,-,. - , # , ~4' X 1._r ;?, , \ - - \,-. I ~ ~, , ~ - 11-1, I I.% / , " ,; / , - -. -, - - z - - - LEGEND: - BIORETENTION AREA, SEE DETAIL BELOW SELF-TREA TING AREA PERVIOUS MEDIAN (POROUS PA VERS& LANDSCAPING AT POCKETS) PER fr5'OUS-LANDSCAPING PROPOSED IMPERVIOUS SURFACE H EXISTING IMPERWOUS SURFACE STORM DRAIN lolopp- DIRECTION OF FLOWS lo rH MODIFIED D-02 CURB INLET / / / 7 <.: /: Ai ?7: ORIMCE / ~ , " ~ , 1\1 I . , ,,~/ I , . , ___,~",/ , - , ,~, , ~,_ & ___ : NU1 , ' -. , 1.:; OFIFICE PLATE '& RANGE 1 ' C - WHERE SHOWN ON PLAN CNNECTION TO CONCRETE. -- . - RI}10E OAMETER (DA) StAX.L E #T Td, WITH S IL 0 - SIZE PER -O(GM CRt 3 DUROMETER NEOPRENE RING. I. ,., . 3,, - 5 8.- - - - - . I , ". - - E ~,;. ; F NOT TO SCALE - 'A . 54 "S A SWMP NO. 13-03 MAINTENANCE AGREEMENT DOCUMENT: YES NO____ RECORDATION NO. ' - PARTY RESPONSIBLE FOR MAINTENANCE: NAME TOLL BROTHERS CONTACT_______________ ADDRESS 725 W TOWN & COUNTRY RD. SUITE 200 ORANGE, CA 92868 PHONE NO. (714) 347-1300 PLAN PREPARED BY: NAME GEORGE O'DA Y ,COMPANY O'DAYc'ONSUL TANTS, INC. ADDRESS 2710 LOKER AVE WEST 0' ......' 200' SUITE 100 . 100' 11111111111111111111111111111111111111i . C'ARLSBAD, CA 92010 SCALE: 1" = 100' PHONE NO. 760) 931-7700 CERTIFICATION RC'E 32014, a 12/31/14 BMP NOTES: THESE BMPS ARE MANDATORY TO BE INSTALLED PER MANUFACTURER'S RECOMMENDATIONS OR THESE PLANS. NO CHANGES TO THE PROPOSED BMPS ON THIS SHEET WITHOUT PRIOR APPROVAL FROM THE CITY ENGINEER. NO SUBSTITUTIONS TO THE MATERIAL OR TYPES OR PLANTING TYPES WITHOUT PRIOR APPROVAL FROM THE CITY ENGINEER. NO OCCUPANCY WILL BE GRANTED UNTIL THE CITY INSPECTION STAFF HAS ,TED THIS PROJECT FOR APPROPRIATE BMP CONSTRUCTION -- AND INSTALLATION SINGLE SHEET AMP EXHIBIT FOR EL CW4IINO REAL WIDENING - -. - -----I ; , .~ I I " * _-L______ ---- ~ , .1 *-,- — __11 7_ - S .......... --5------- /bU-9i1—//UU Surveying . ENGINEER OF WO1 REVISION DESCRIPTION 'OTHER APPROVAL CITY APPROVAL I L Fax: 760-931-8680 ATE ,,.: __ - I I . 1. - -_ ; -. . www.odayconsuitants.com GEORGE O'DAY RCE: 32014 - - G: \101307\SWMP\ECR—Widenjna\Ip—Submittal 2\W— ATTACH MEN T1'0.dwa Feb 25. 2014 8:11am H .' I: ...- E •', ...I ,.. ' ............H I] 1 I I I I El] I I I I Pi I I I I 1 I 11 I I Hydromodification and Water Oualitv Supplemental Calculations to the LID Calculator I In order to meet Hydromodification requirements outlined in the Final I Hydromodification Plan prepared for the County of San Diego on March 2011 by Brown and Caldwell, the BMP Calculator was utilized to determine the minimum surface area and volume required for each BMP. See the calculator output attached. I Per Table 7-4 of the Final Hydromodification Plan, Sizing Factors For the Flow Through Planter are depicted below. A lower flow threshold of 0.5Q2 was utilized based on the I downstream analysis provided by Wayne Chang and included in Attachment #13. Rain Gauge= Oceanside I Soil Type: D Existing Slope: Flat & Moderate = 0.07, for Steep= 0.05 I Narrow Median Bioretention Calculations Due to site constraints, where the street is super elevated near an intersection, Basin's D, I E and G have a modified bioretention section, see Attachment #10. The entire volume per the LID calculator output shall be contained in V2, although 4" of water will pond in these bioretention areas. This conservative calculation means that 43" of gravel will store I water under the 18" soil/compost layer in lieu of 18" in the standard section. See calculations below: I Flow-Thru Planter Sizing Factors (Table 7-4): V1= 0.0583, V2=0.0420 If all of Vi is in V2, then 0.0583+0.0420= 0.1003 Depth of Gravel= 0.1003/(0.07*0.40)= 3.58'*12= 43 inches I The orifice size for these basins from the LID Calculator is based on a depth of water or head over the orifice typical of the standard section. See calculations below for the I adjusted orifice diameters, based on the larger head. Orifice Equation Q= 0.67A[ (2*32.2*d)" (.5)] I Basin D Orifice Flow, Q= 0.028cfs, A=0.002 1sf, d=0.60in I Basin E Orifice Flow, Q=0.058cfs, A=0.0044sf, d=0.9in I Bash-4) Orifice Flow, Q=0.074 cfs, A=0.0057sf, d=i.Oin I I Project Summary Project Name El Camino Real Widening Project Applicant Shapell Homes Jurisdiction City of Carlsbad Parcel (APN) 20801040 Hydrologic Unit Carlsbad M 1Wagc0W 2 — Compliance Basin Summary Basin Name: Basin A- Near Cannon Receiving Water: SE Side of ECR near 8X8 Rainfall Basin Oceanside Mean Annual Precipitation (inches) 13.3 Project Basin Area (acres): 1.69 Watershed Area (acres): 11.52 SCCWRP Lateral Channel Susceptibility (H, M, L): Low (Lateral) SCCWRP Vertiflcal Channel Susceptiblity (H, M, L): Low (Vertical) Overall Channel Susceptibility (H, M, L): LOW Lower Flow Threshold (% of 2-Year Flow): 0.5 Drainage Management Area Summary ID Type BMP ID Description Area (ac) Pre-Project Cover Post Surface Type Drainage Soil Slope 26930 Drains to LID BMP 1 DMA A1-1 0.16 Impervious (Pre) Concrete or asphalt Type D (high runoff - clay Flat - slope (less aol... 26931 Drains to LID BMP 1 DMA A11-2 0.02 Pervious (Pre) Landscaping Type 0 (high runoff - clay Steep (greater 10%) aol... 26932 Drains to LID BMP 1 DMA A1-3 0.1 Pervious (Pre) Concrete or asphalt Type D (high runoff- clay Flat - slope (less soi... 26933 Drains to LID BMP 1 DMA A1-4 0.02 Impervious (Pre) Pervious concrete or asphalt Type D (high runoff - clay Flat - slope (less soi... 26934 Drains to LID BMP 2 DMA A2-1 0.56 Impervious (Pre) Concrete or asphalt Type D (high runoff - clay Flat - slope (less soi... 26935 Drains to LID BMP 2 DMA A2-2 0.07 Pervious (Pre) Landscaping Type D (high runoff - clay Steep (greater 10%) aol.. http://uknow.brwncald.comlwastewater/Toolkits/Watershed/SiteToolkit/ReportResult.aspx?pid= 138617&bidSDC-000 I &sicn... 5/18/2013 IM A rt RMS ON .- 00 '00 00 - IM -, M M - - 'ag2 - 26936 Drains to LID I BMP 2 DMA A2-3 0.46 I Pervious (Pre) I Concrete or asphalt I Type D (high runoff - clay Isoi... I Steep (greater 10%) I 26937 Drains to LID BMP 2 DMA A2 0.3 Impervious (Pre) Pervious concrete or asphalt Type D (high runoff - day Flat - slope (less LID Facility Summary BMP ID Type Description Plan Area (sqft) Volume 1(cft) Volume 2(cft) Orifice Flow (cfs) Orifice Size (inch) BMP 1 Flow-Through Planter Bioretention Area S. side of 446+73 305 254 183 0.061 1.00 BMP 2 Flow-Through Planter Bioretention Area N. side of 446+73 1268 1057 761 0.304 3.00 http://uknow.brwncald.comlwastewater/Toolkits/Watershed/SiteToolkit/ReportResult.aspx?pid 138617&bidSDC-000 I &sicn... 5/18/2013 —Owrt 1t .• no ow — — — — AnPagloW. 3 — Project Summary Project Name El Camino Real Widening Project Applicant Shapell Homes Jurisdiction City of Carlsbad Parcel (APN) 20801040 Hydrologic Unit Carlsbad Compliance Basin Summary Basin Name: Basin B- N. of Cannon Receiving Water: Storm Drain near Crestview Rainfall Basin Oceanside Mean Annual Precipitation (inches) 13.3 Project Basin Area (acres): 1.47 Watershed Area (acres): 11.50 SCCWRP Lateral Channel Susceptiblity (H, M, L): Low (Lateral) SCCWRP Vertifical Channel Susceptiblity (H, M, L): Low (Vertical) Overall Channel Susceptibility (H, M, L): LOW Lower Flow Threshold (% of 2-Year Flow): 0.5 Drainage Management Area Summary ID Type BMP ID Description Area (ac) Pre-Project Cover Post Surface Type Drainage Soil Slope 27070 Drains to LID BMP 1 DMA B1-1 0.1 Impervious (Pie) Concrete or asphalt Type D (high runoff- clay soi... Flat - slope (less 27071 Drains to LID BMP 1 DMA B1-2 0.01 Pervious (Pie) Landscaping Type D (high runoff - clay soi... Steep (greater 10%) 27072 Drains to LID BMP 1 DMA 131-3 0.08 Pervious (Pie) Concrete or asphalt Type D (high runoff- clay soi... Steep (greater 10%) 27073 Drains to LID BMP 1 DMA 131-4 0.05 Impervious (Pie) Pervious concrete or asphalt Type D (high runoff - clay Soi ... Flat - slope (less 27153 Drains to LID BMP 2 DMA B2-1 0.12 Impervious (Pre) Concrete or asphalt Type D (high runoff- clay soi... Flat - slope (less 27154 Drains to LID BMP 2 DMA B2-2 0.03 Pervious (Pie) Landscaping Type D (high runoff - clay soi... Steep (greater 10%) http://uknow.brwncald.comlwastewater/Toolkits/Watershed/SiteToolkit/ReportResult.aspx?pid= 13861 7&bid=SDC-000 1 &sic=n... 5/23/2013 t FAM - — — — — .— ) —, — — — — — jWag4M 3 — 27155 Drains to LID BMP 2 DMA 132-3 0.07 Pervious (Pie) Concrete or asphalt Type D (high runoff - clay Steep (greater 10%) soi... 27156 Drains to LID BMP 2 DMA 1324 0.03 Impervious (Pre) Pervious concrete or asphalt Type D (high runoff - clay Flat - slope (less soi... 27158 Drains to LID BMP 3 DMA 63-1 0.04 Impervious (Pre) Concrete or asphalt Type D (high runoff - clay Flat - slope (less soi.. 27159 Drains to LID BMP 3 DMA 133-2 0.02 Pervious (Pre) Landscaping Type D (high runoff - clay Steep (greater 10%) soi... 27160 Drains to LID BMP 3 DMA 133-3 0.03 Pervious (Pie) Concrete or asphalt Type D (high runoff - clay Steep (greater 10%) soi... 27161 Drains to LID BMP 3 DMA 133-4 0.03 Impervious (Pre) Pervious concrete or asphalt Type D (high runoff- clay Flat- slope (less soi... 27163 Drains to LID BMP 4 DMA 64-1 0.09 Impervious (Pre) Concrete or asphalt Type D (high runoff - clay Flat - slope (less soi... 27164 Drains to LID BMP 4 DMA B4-2 0.05 Pervious (Pie) Landscaping Type D (high runoff- clay Steep (greater 10%) soi... 27165 Drains to LID BMP 4 DMA 134-3 0.06 Pervious (Pre) Concrete or asphalt Type D (high runoff - Clay Steep (greater 10%) $oi... 27166 Drains to LID BMP 4 DMA 1344 0.06 Impervious (Pre) Pervious concrete or asphalt Type D (high runoff- clay Flat- slope (less soi... 27173 Drains to LID BMP 5 DMA 65-1 0.07 Impervious (Pie) Concrete or asphalt Type D (high runoff- clay Flat- slope (less soi... 27174 Drains to LID BMP 5 DMA B5-2 0.02 Pervious (Pre) Landscaping Type D (high runoff- clay Steep (greater 10%) soi... 27175 Drains to LID BMP 5 DMA 135-3 0.03 Pervious (Pre) Concrete or asphalt Type D (high runoff - clay Steep (greater 10%) soi... 27176 Drains to LID BMP 5 DMA B5-4 0.03 Impervious (Pre) Pervious concrete or asphalt Type D (high runoff - clay Flat - slope (less soi... 27178 Drains to LID BMP 6 DMA B6-1 0.03 Impervious (Pie) Concrete or asphalt Type D (high runoff - clay Flat - slope (less soi... 27179 Drains to LID BMP 6 DMA B6-2 0.06 Pervious (Pie) Concrete or asphalt Type D (high runoff- clay Steep (greater 10%) soi... 27180 Drains to LID BMP 6 DMA 66-3 0.03 Impervious (Pie) Pervious concrete or asphalt Type D (high runoff - clay Flat - slope (less soi... 27182 Drains to LID BMP 7 DMA 67-1 0.06 Impervious (Pre) Concrete or asphalt Type D (high runoff- clay Flat - slope (less soi... 27183 Drains to LID BMP 7 DMA B7-2 0.01 Pervious (Pre) Landscaping Type D (high runoff- clay Steep (greater 10%) soi... 27184 Drains to LID BMP 7 DMA 67-3 0.06 Pervious (Pie) Concrete or asphalt Type D (high runoff - clay Steep (greater 10%) soi... hftp ://uknow.brwncald.comlwastewater/Toolkits/Watershed/SiteToolkit/ReportResult.aspx?pid= 13861 7&bid=SDC-000 1 &sic=n... 5/23/2013 - Wd It , ___ ____ 3 27185 Drains to LID BMP 7 DMA 1374 0.03 Impervious (Pre) Pervious concrete or asphalt Type D (high runoff- clay Flat - slope (less soi... 27187 Drains to LID BMP 8 DMA 138-1 0.06 Impervious (Pre) Concrete or asphalt Type D (high runoff - clay Flat - slope (less soi... 27188 Drains to LID BMP 8 DMA 138-2 0.02 Pervious (Pre) Landscaping Type D (high runoff - clay Steep (greater 10%) soi... 27189 Drains to LID BMP 8 DMA 138-3 0.03 Pervious (Pre) Concrete or asphalt Type D (high runoff - clay Steep (greater 10%) soi... 27190 Drains to LID BMP 8 DMA B84 0.03 Impervious (Pre) Pervious concrete or asphalt Type D (high runoff - clay Flat - slope (less soi... LID Facility Summary BMP ID Type Description Plan Area (sqft) Volume 1(cft) Volume 2(cft) Orifice Flow (cfs) Orifice Size (inch) BMP 1 Flow-Through Planter Bioretention at Median 220 183 132 0.052 1.00 BMP 2 Flow-Through Planter Bioretention at Median 197 164 118 0.054 1.00 BMP 3 Flow-Through Planter Bioretention at Median 85 71 51 0.025 0.8 BMP 4 Flow-Through Planter Bioretention at Median 174 145 104 0.055 1.00 BMP 6 Flow-Through Planter Bioretention at Median 172 143 103 0.026 0.8 BMP 7 Flow-Through Planter Bioretention at Median 162 135 97 0.033 0.9 BMP 8 Flow-Through Planter Bioretention at Median 87 73 52 0.031 0.9 BMP 5 Flow-Through Planter Bioretention at Median 88 73 52 0.034 0.9 http ://uknow.brwncald.comlwastewater/Toolkits/Watershed/SiteToolkit/ReportResult.aspx?pid 13861 7&bidSDC-000 1 &sicn... 5/23/2013 Mt rt it INN OW 11w, . ON (Pag2 1 -~, ~~ IQ C-,0 Project Summary Project Name El Camino Real Widening Project Applicant Shapell Homes Jurisdiction City of Carlsbad Parcel (APN) 20801040 Hydrologic Unit Carlsbad Compliance Basin Summary Basin Name: Basin C- N. of Crest View Receiving Water: Ex. 24' Storm Drain outlet S. of Crestview Rainfall Basin Oceanside Mean Annual Precipitation (inches) 13.3 Project Basin Area (acres): 1.62 Watershed Area (acres): 11.52 SCCWRP Lateral Channel Susceptiblity (H, M, L): Low (Lateral) SCCWRP Vertifical Channel Susceptiblity (H, M, L): Low (Vertical) Overall Channel Susceptibility (H, M, L): LOW Lower Flow Threshold (% of 2-Year Flow): 0.5 Drainage Management Area Summary ID Type BMP ID Description Area (ac) Pre-Project Cover Post Surface Type Drainage Soil Slope 26958 Drains to LID BMP 1 DMA Cl 0.5 Impervious (Pre) Concrete or asphalt Type D (high runoff- clay Flat - slope (less soi... 26959 Drains to LID BMP 1 DMA C2 0.83 Pervious (Pro) Landscaping Type D (high runoff- clay Steep (greater 10%) aol... 26960 Drains to LID BMP 1 DMA C3 0.29 Pervious (Pre) Concrete or asphalt Type D (high runoff- clay Moderate (5- 10%) soi... LID Facility Summary BMP ID Type Description Plan Area (sqft) Volume 1(cft) Volume 2(cft) Orifice Flow (cfs) Orifice Size (inch) BMP 1 Flow-Through Planter Bioretention near Crestview 970 809 582 0.271 3.00 hap ://uknow.brwncald.comlwastewater/Toolkits/Watershed/SiteToolkit/ReportResult.aspx?pid 13861 7&bidSDC-000 1 &sicnu... 5/5/2013 rt PMW M WX M, M- M0 M .']= M &WagcoM 1 Project Summary Project Name El Camino Real Widening Project Applicant Shapell Homes Jurisdiction City of Carlsbad Parcel (APN) 20801040 Hydrologic Unit Carlsbad Compliance Basin Summary Basin Name: Basin D- From HP S. of Lisa Receiving Water: Box Culvert at Kelly Rainfall Basin Oceanside Mean Annual Precipitation (inches) 13.3 Project Basin Area (acres): 0.17 Watershed Area (acres): 11.50 SCCWRP Lateral Channel Susceptibility (H, M, L): Low (Lateral) SCCWRP Vertifical Channel Susceptiblity (H, M, L): Low (Vertical) Overall Channel Susceptibility (H, M, L): LOW Lower Flow Threshold (% of 2-Year Flow): 0.5 Drainage Management Area Summary SAr)P ID Type BMP ID Description Area (ac) Pre-Project Cover Post Surface Type Drainage Soil Slope 27130 Drains to LID BMP 1 DMA Dl 0.08 Impervious (Pre) Concrete or asphalt Type D (high runoff - clay Flat - slope (less soi ... 27131 Drains to LID BMP 1 DMA D2 0.01 Pervious (Pre) Landscaping Type D (high runoff- clay soi ... Steep (greater 10%) 27132 Drains to LID BMP 1 DMA D3 0.07 Pervious (Pre) Concrete or asphalt Type D (high runoff - clay Steep (greater 10%) soi ... 27133 Drains to LID BMP 1 DMA D4 0.01 Impervious (Pre) Pervious concrete or asphalt Type D (high runoff - clay Flat - slope (less so'... LID Facility Summary BMP ID Type Description Plan Area (sqft) Volume 1(cft) Volume 2(cft) Orifice Flow (cfs) Orifice Size (inch) BMP 1 Flow-Through Planter Bioretenlion at Median 187 156 112 0.028 0.9 http ://uknow.brwncald.com/wastewater/Toolkits/Watershed/SiteToolkit/ReportResult.aspx?pid= 13861 7&bidSDC-000 1 &sicn... 5/14/2013 Project Summary Project Name El Camino Real Widening Project Applicant Shapell Homes Jurisdiction City of Carlsbad Parcel (APN) 20801040 Hydrologic Unit Carlsbad irt 1t PagIT 1 Compliance Basin Summary Basin Name: Basin E- N. of Lisa Street Receiving Water: Box Culvert at Kelly Rainfall Basin Oceanside Mean Annual Precipitation (inches) 13.3 Project Basin Area (acres): 0.45 Watershed Area (acres): 11.50 SCCWRP Lateral Channel Susceptiblity (H, M, L): Low (Lateral) SCCWRP Vertificat Channel Susceptibility (H, M, L): Low (Vertical) Overall Channel Susceptibility (H, M, L): LOW Lower Flow Threshold (% of 2-Year Flow): 0.5 Drainage Management Area Summary ID Type BMP ID Description Area (ac) Pre-Project Cover Post Surface Type Drainage Soil Slope 27124 Drains to LID BMP 1 DMA El 0.12 Impervious (Pre) Concrete or asphalt Type D (high runoff - clay soi... Flat - slope (less 27125 Drains to LID BMP 1 DMA E2 0.04 Pervious (Pie) Landscaping Type D (high runoff - clay Steep (greater 10%) soi... 27126 Drains to LID BMP 1 DMA E3 0.17 Pervious (Pre) Concrete or asphalt Type D (high runoff- clay Steep (greater 10%) soi... 27127 Drains to LID BMP 1 DMA E4 0.05 Impervious (Pre) Pervious concrete or asphalt Type D (high runoff - clay Flat - slope (less soi... LID Facility Summary BMP ID Type Description Plan Area (sqft) Volume 1(cft) Volume 2(cft) Orifice Flow (cfs) Orifice Size (inch) BMP 1 Flow-Through Planter Bioretenlion at 8' Median 446 372 268 0.058 1.00 http ://uknow.brwncald.com/wastewater/Toolkits/Watershed/SiteToolkitlReportResult.aspx?pid= 1386 17&bidSDC-000 1 &sicn... 5/17/2013 I I I I I I I I 1 I I I I I I I I I I 576 I 473 -OO UU ttA ,, £7S1 AC = 0.20 AC • • EXiST AC :__•:- PROPOSED PER ViVt/S = 0.13 AC EXiST PER I'FOIJS PROPOSED AC/CO/IC. = 0.13 AC EXiST PERIlOUS PROPOSED PER frl0l/S = 0.01 AC 0' 30' SCALE: 1" = 30' G:\101307\Exhi bits\ECR\BIOBASINF.dwg Jun 12, 2013 O: 24am EXHIBIT FOR B/ORETEN liON BASIN r iW4RJA ACRES PROPERTY PREPARED 6/5/2013 Project Summary Project Name El Camino Real Widening Project Applicant Shapell Homes Jurisdiction City of Carlsbad Parcel (APN) 20801040 Hydrologic Unit Carlsbad - FAW Ran - - = - - - - - - - M - - MagedW2 Compliance Basin Summary Basin Name: Basin G- Super Elevated to Median at Marja Acres Receiving Water: Kelly Box Culvert Rainfall Basin Oceanside Mean Annual Precipitation (inches) 13.3 Project Basin Area (acres): 1.86 Watershed Area (acres): . 11.50 SCCWRP Lateral Channel Susceptiblity (H, M, L): Low (Lateral) SCCWRP Vertifical Channel Susceptiblity (H, M, L): Low (Vertical) Overall Channel Susceptibility (H, M, L): LOW Lower Flow Threshold (% of 2-Year Flow): 0.5 Drainage Management Area Summary ID Type BMP ID Description Area (ac) Pre-Project Cover Post Surface Type Drainage Soil Slope 28010 Drains to LID BMP I DMA G1-1 0.19 Impervious (Pre) Concrete or asphalt Type D (high runoff - clay Flat - slope (less soi... 28011 Drains to LID BMP 1 DMA G1-2 0.03 Pervious (Pre) Landscaping Type D (high runoff - clay Steep (greater 10%) soi... 28012 Drains to LID BMP 1 DMA G1-3 0.1 Pervious (Pre) Concrete or asphalt Type D (high runoff- clay Steep (greater 10%) 501... 28013 Drains to LID BMP I DMA.G1-4 0.06 Pervious (Pre) Landscaping Type D (high runoff - clay Flat - slope (less soi... 28014 Drains to LID BMP 2 DMA G2-11 0.16 Impervious (Pre) Concrete or asphalt Type D (high runoff- clay Flat- slope (less soi... 28015 Drains to LID BMP 2 DMA G2-2 0.02 Pervious (Pre) Landscaping Type D (high runoff -clay Steep (greater 10%) 501... http://uknow.brwnca1d.com/wastewater/Too1kits/ WatershedlSiteToolkitlReportResult.aspx?pid 13861 7&bidSDC-000 1 &sicn. - - 6/14/2013 - R1 Roft - - - - - - - - - - - - - N Wge JMIJ2 - 28016 Drains to LID BMP 2 DMA G2-3 0.1 Pervious (Pre) Concrete or asphalt Type D (high runoff - clay sal... Steep (greater 10%) 28017 Drains to LID BMP 2 DMA G2-4 0.06 Impervious (Pre) Pervious concrete or asphalt Type D (high runoff - clay aol... Flat - slope (less 28018 Drains to LID BMP 3 DMA G3-1 0.17 Impervious (Pre) Concrete or asphalt Type D (high runoff - clay soi... Flat - slope (less 28019 Drains to LID BMP 3 DMA G3-2 0.02 Pervious (Pie) Landscaping Type D (high runoff - clay soi... Steep (greater 10%) 28020 Drains to LID BMP 3 DMA G3-3 0.09 Pervious (Pie) Concrete or asphalt Type D (high runoff- clay soi... Steep (greater 10%) 28021 Drains to LID BMP 3 DMA G3-4 0.09 Impervious (Pre) Pervious concrete or asphalt Type D (high runoff - clay soi... Flat - slope (less 28023 Drains to LID BMP 4 DMA G4-1 0.38 Impervious (Pre) Concrete or asphalt Type D (high runoff - clay 501... Flat - slope (less 28024 Drains to LID BMP 4 DMA G4-2 0.02 Pervious (Pre) Landscaping Type D (high runoff- clay aol... Steep (greater 10%) 28026 Drains to LID BMP 4 DMA G4-3 0.14 Pervious (Pre) Concrete or asphalt Type D (high runoff- clay sal... Steep (greater 10%) 28027 Drains to LID BMP 4 DMA G4-4 0.23 Impervious (Pre) Pervious concrete or asphalt Type D (high runoff- clay sal... Flat - slope (less LID Facility Summary BMP ID Type Description Plan Area (sqft) Volume 1(cft) Volume 2(cft) Orifice Flow (cfs) Orifice Size (inch) BMP 1 Flow-Through Planter Bioretention 299 249 179 0.074 1.00 BMP 2 Flow-Through Planter Bioretention 279 233 167 0.076 1.00 BMP 3 Flow-Through Planter Bioretention 256 213 154 0.085 2.00 BMP 4 Flow-Through Planter Bioretention 407 339 244 0.189 2.00 http://uknow.brwncald.com/wastewater/Toolkits/Watershed/SiteToolkit/ReportResult.aSPX?Pid 138617&bidSDC-000 1 &sic=n... 6/14/2013 - ilii RM = M - - - M M - - - - - - ag 2 - Project Summary Project Name El Camino Real Widening Project Applicant Shapell Homes Jurisdiction City of Carlsbad Parcel (APN) 20801040 Hydrologic Unit Carlsbad Compliance Basin Summary Basin Name: Basin F-I- S. of Kelly Receiving Water: Box Culvert at Kelly Rainfall Basin Oceanside Mean Annual Precipitation (inches) 13.3 Project Basin Area (acres): 3.19 Watershed Area (acres): 11.52 SCCWRP Lateral Channel Susceptiblity, (H, M, L): Low (Lateral) SCCWRP Vertifical Channel Susceptiblity (H, M, L): Low (Vertical) Overall Channel Susceptibility (H, M, L): LOW Lower Flow Threshold (% of 2-Year Flow): 0.5 Drainage Management Area Summary ID J Type BMP ID Description Area (ac) Pre-Project Cover Post Surface Type Drainage Soil Slope 26963 Drains to LID BMP 1 DMA HI-i 0.48 Impervious (Pre) Concrete or asphalt Type D (high runoff - clay Flat - slope (less 26964 Drains to LID BMP 1 DMA H1-2 0.58 Pervious (Pre) Landscaping Type D (high runoff- clay Steep (greater 10%) 26965 Drains to LID BMP 1 DMA H1-3 0.36 Pervious (Pre) Concrete or asphalt Type D (high runoff - clay Steep (greater 10%) soi 26966 Drains to LID BMP 1 DMA H1-4 0.2 Impervious (Pre) Pervious concrete or asphalt Type D (high runoff- clay Flat - slope (less 26968 Drains to LID BMP 2 DMA H2-1 0.42 Impervious (Pre) Concrete or asphalt Type D (high runoff- clay Flat - slope (less 26969 Drains to LID BMP 2 DMA H2-2 0.46 Pervious (Pre) Landscaping Type D (high runoff- clay Steep (greater 10%) http://uknowbrwncald.comlwastewater/Toolkits/Watershed/SiteToolkit/ReportResult.aspx?pidr= 1386 17&bid=SDC-000 1 &sic=nu... 5/7/2013 - ORA RM - = - = - - - - = = - = - EWagAW2 - 26970 Drains to LID BMP 2 DMA 1-12-3 0.3 Pervious (Pre) Concrete or asphalt Type D (high runoff- clay Steep (greater 10%) soi... 27026 Drains to LID BMP 3 DMA 1-13-1 0.21 Impervious (Pre) Concrete or asphalt Type D (high runoff - clay Flat - slope (less soi... 27027 Drains to LID BMP 3 DMA 1-13-2 0.08 Pervious (Pre) Landscaping Type D (high runoff- clay Flat- slope (less soi... 27028 Drains to LID BMP 3 DMA H3-3 0.1 Pervious (Pre) Concrete or asphalt Type D (high runoff - clay Moderate (5- 10%) soi... LID Facility Summary BMP ID Type ] Description Plan Area (sqft) Volume 1(cft) Volume 2(cft) Orifice Flow (cfs) Orifice Size (inch) BMP 1 Flow-Through Planter Bioretention at Station 474+50 1063 886 637 0.304 3.00 BMP 2 Flow-Through Planter Bioretention at Toe S. of Box Culvert 860 717 516 0.209 2.00 BMP 3 Flow-Through Planter I Bioretention adjacent Box Culvert 329 274 197 0.076 1.00 http ://uknow.brwncald.comlwastewater/Toolkits/ Watershed/SiteToolkit/ReportResult.aspx?pid= 13861 7&bidSDC-000 1 &sic=nu... 5/7/2013 Iort WRit = = = = Paf 1 Project Summary Project Name El Camino Real Widening Project Applicant Shapell Homes Jurisdiction City of Carlsbad Parcel (APN) 20801040 Hydrologic Unit Carlsbad Compliance Basin Summary Basin Name: Basin I- N. of Kelly Receiving Water: Bioretention Area N. of Box Culvert Rainfall Basin Oceanside Mean Annual Precipitation (inches) 13.3 Project Basin Area (acres): 1.13 Watershed Area (acres): 11.52 SCCWRP Lateral Channel Susceptiblity (H, M, L): Low (Lateral) SCCWRP Vertifical Channel Susceptiblity (H, M, L): Low(Vertical) Overall Channel Susceptibility (H, M, L): LOW Lower Flow Threshold (% of 2-Year Flow): 0.5 Drainage Management Area Summary ID Type BMP ID Description Area (ac) Pre-Project Cover Post Surface Type Drainage Soil Slope 27031 Drains to LID BMP 1 DMA I-i 0.51 Impervious (Pre) Concrete or asphalt Type D (high runoff - clay Flat - slope (less soi... 27032 Drains to LID BMP 1 DMA 1-2 0.17 Pervious (Pre) Landscaping Type D (high runoff - clay so'... Flat - slope (less 27033 Drains to LID BMP 1 DMA 1-3 0.37 Pervious (Pre) Concrete or asphalt Type D (high runoff - clay Flat - slope (less soi... 27034 Drains to LID BMP I DMA 1-4 0.08 Impervious (Pre) Pervious concrete or asphalt Type D (high runoff - clay Sol Flat - slope (less LID Facility Summary BMP ID Type Description Plan Area (sqft) Volume 1(cft) Volume 2(cft) Orifice Flow (cfs) Orifice Size (inch) BMP 1 Flow-Through Planter Bioretenton N. of Box Culvert 1180 982 708 0.211 2.00 http://uknow.brwncald.comlwastewater/Toolkits/Watershed/SiteToolkit/ReportResult.aspx?pid 138617&bidSDC-000 1 &sic=n... 5/14/2013 - rt RM - - - - - - - - - - - - - ag'2 Project Summary Project Name El Camino Real Widening Project Applicant Shapell Homes Jurisdiction City of Carlsbad Parcel (APN) 20801040 Hydrologic Unit Carlsbad Compliance Basin Summary Basin Name: Basin J- S. of Tamarack Receiving Water: Kelly Drive Box Culvert Rainfall Basin Oceanside Mean Annual Precipitation (inches) 13.3 Project Basin Area (acres): 0.86 Watershed Area (acres): 11.50 SCCWRP Lateral Channel Susceptiblity (H, M, L): Low (Lateral) SCCWRP Vertifical Channel Susceptiblity (H, M, L): Low (Vertical) Overall Channel Susceptibility (H, M, L): LOW Lower Flow Threshold (% of 2-Year Flow): 0.5 Drainage Management Area Summary ID Type BMP ID Description Area (ac) Pre-Project Cover Post Surface Type Drainage Soil Slope 27113 Drains to LID BMP 1 DMA J1-2 0.44 Impervious (Pre) Concrete or asphalt Type D (high runoff - clay Flat - slope (less soi... 27114 Drains to LID BMP 1 DMA J1-2 0.06 Pervious (Pre) Landscaping Type D (high runoff - clay Flat - slope (less soi... 27115 Drains to LID BMP 1 DMA J1-3 0.15 Pervious (Pre) Concrete or asphalt Type D (high runoff - clay Flat - slope (less soi... 27116 Drains to LID BMP 1 DMA J1-4 0.05 Impervious (Pie) Pervious concrete or asphalt Type 0 (high runoff - clay Flat - slope (less soi... 27117 Drains to LID BMP 2 DMA J2-1 0.05 Impervious (Pre) Concrete or asphalt Type D (high runoff - clay Flat - slope (less soi... 27118 Drains to LID BMP 2 DMA J2-2 0.02 Pervious (Pre) Pervious concrete or asphalt Type D (high runoff - clay Flat - slope (less soi... http://uknow.brwncald.comlwastewater/Toolkits/Watershed/SiteToolkit/ReportResult.aspx?pid 13861 7&bidSDC-000 1 &sicn... 5/14/2013 - rt K1 M iii 'ag=W 2 I . 1• 27119 Drains to LID I BMP 2 I DMA J2-3 I 0.06 I Pervious (Pre) Concrete or asphalt I Type D (high runoff - clay Isoi... I Flat - slope (less I 27120 Drains to LID I BMP 2 DMA .124 0.03 Impervious (Pre) Pervious concrete or asphalt Type D (high runoff - clay Flat - slope (less Sol LID Facility Summary BMP ID Type Description Plan Area (sqft) Volume 1(cft) Volume 2(cft) Orifice Flow (cfs) Orifice Size (inch) BMP 1 Flow-Through Planter Bioretention Area 1 475 396 285 0.155 2.00 BMP 2 Flow-Through Planter Bioretention Area 2 189 157 113 0.029 0.9 http ://uknow.brwncald.comlwastewater/Toolkits/WatershedlSiteToolkit/ReportResultaspx?pid= 13861 7&bid=SDC-000 1 &sicn... 5/14/2013 I I I Li I Li I I LI 1 I I I I I I I I I I ATTACHMENT 12 SOIL RECOMMENDATIONS FOR BIORETENTION AND PERVIOUS I PAVEMENT NATIVE SOIL We assumed the soil at the site is Type 'D' as shown on the BMP Calculator Output in Attachment 11. In the Supplemental to the Updated Geotechnical Investigation for Rancho Costera (Formerly Robertson Ranch West Village) for Shappell Homes, prepared by GeoSoils, Inc. on June 6, 2011, (Reference 1) the calculated infiltration rates of 0.18 in/hr for the artificial fill areas and between 0.16 and 0.06 in/hour for the bedrock materials were found at the site. According to the County of San Diego Guidelines for Determining Significance, Surface Water Quality, dated July 30, 2007, (Reference 2) soil infiltration rates for Type 'D' soil are 0 to 0.05 inches per hour. Conclusively, the soil on site has slightly higher infiltration rates then the minimum infiltration rates delineated by the County of San Diego for Type 'D'. However, in order to maintain a more conservative IMP design we will use Type 'D' for our IMP calculations. Excerpts from reference 1 and 2 above are attached below. I Li I I I I I I I I I I Li I I I I I I I I I I I I I I I -LFr2J cj / CR (i ,wf) exhibit an adequate FOS (i.e., >1 .5) against surficial failure, provided that the sI6pe'are i properly constructed and maintained, under normal rainfall. Terrace deposits and Santiago Formation bedrock contain granular, sandy soil. If sandy soils with a cohesion of less than 200 psf are used on slope faces derived from these deposits, the slopes may have surficial stability/erosion issues and perhaps a FOS against surficial instability of less than 1.5. Planting and management of surficial drainage is imperative to the surficial performance of slopes. Typically, similar to coastal bluff retreat, a surficial erosion rate (average) of about 11/4 inches/year for natural and unprotected sandy slopes may be assumed. Foot traffic and other activities that exacerbate surficial erosion should not be allowed to occur on slopes. Failure to adhere to these conditions may drastically increase and localize surficial erosion, requiring mitigation, so that head ward erosion does not result, and impact roadways, pads, and other improvements. Planned Fill Over Cut Slopes Fill over cut slopes shown on Plates 1 and 3 are generally considered to be grossly stable. However, the cut/fill transition that daylights at the slope face represents a permeability contrast that will accumulate water (i.e., perched groundwater), resulting in seepage at the slope face. Such seepage will saturate near surface soils, resulting in loss of soil strength and an increased potential for surficial slope failure(s). In order to mitigate this condition, as well as the potential for perched groundwater up-gradient, fill over cut slopes should be reconstructed as a stabilization fill slopes. In the case of the larger fill (up to approximately 45 feet) over cut slope above El Camino Real (see Plate 2, Cross Section F-F') the fill key may be provided with a subdrain/backdrain as recommended in Appendix F. As stated previously, the backcut was considered stable for Cross Section F-F' due the anticipated 2:1 inclination (Plate 2). Furthermore, the face cuts and backcuts up to 1.5:1 (h:v) are considered stable (FOS >1.2) INFILTRATION TESTING It is our understanding that the controlling authorities are requiring onsite Best Management Practices (BMP's) to clarify and filter onsite storm water run-off within the project. Currently, it is unknown what type of BMP will be utilized for the project (i.e., bio-swales, detention/infiltration basins, sand filters, etc.), however; detention/infiltration basin BMP's are generally utilized for residential developments to clarify and filter onsite storm water during rain events. Three (3) infiltration tests were conducted to evaluate site soils with respect to anticipated BMP's onsite. One (1) infiltration test was conducted within previously compacted fill materials onsite (depth of approximately ±3 feet) and two (2) infiltration tests were Shapell ------__----- Homes wa 6145-Al-SC Rancho Costera Carlsbad June 6, 2011 File ewp9.,61005145 1 Page GeoSolls, Inc. [ r F conducted within the bedrock materials onsite (depth of approximately ±3 feet). Infiltration i testing was performed to evaluate potential site conditions with respect to the anticipated I detention/infiltration systems and/or other BMP's to retain and filter onsite storm water. Infiltration testing was performed in general conformance with the American Society for Testing and Materials (ASIM) designation D 3385 guidelines, by an engineering geologist from our firm. The field infiltration test data is provided in Appendix E. Procedures for testing are outlined briefly below: Double-Ring Infiltration Test Procedure 1. An approximate area of 4 feet by 4 feet was cleared and excavated to a depth of I approximately ±3 feet to evaluate the onsite compacted fill and bedrock materials, and a level surface prepared. 1 2. The outer (annular) ring of the double-ring infiltrometer test apparatus was driven into the exposed earth materials, approximately ±2 to ±3 inches in depth, utilizing a wooden block and heavy sledge hammer. The inner ring of the double-ring infiltrometer test apparatus was also driven into the I exposed earth materials, approximately ±2 to ±3 inches in depth, utilizing the same block and sledge hammer technique. Both rings were leveled prior to infiltration I testing. Measurement depth gages were installed in both the inner and outer ring, and water I poured into both rings to same depth within each ring. The graduated mariotte tubes were connected to both the inner and outer rings and I filled with clear water for the infiltration testing. After equalization of the inner and outer rings, a periodic flow was started from the I graduated mariotte tubes. When the fluid level became constant within the inner and outer rings, measurements from the graduated mariotte tubes, to the nearest millimeter began. ITesting: Both ground and water temperatures were recorded during testing. The volume of liquid utilized was measured from the I graduated mariotte tubes at intervals of 30 minutes based on the infiltration rate achieved. Due to the relatively low infiltration rates obtained during testing within the artificial fill I and bedrock materials, the testing was suspended after 2 hours at each location. I Locations: The locations of the infiltrometer tests were chosen to give a general representation of the anticipated infiltration rate of the I Shapeil Homes W. 0. 6145-Al-SC Rancho Costera, Carlsbad June 6, 2011 i File:e: Np9\6100\6145a1 ,stt Page 10 GeoSoil. Inc. onsite earth materials in relation the anticipated detention/infiltration systems and/or other BMP's selected by design engineer. The approximate locations of the infiltration tests conducted are provided on the enclosed Plate 1. I Accuracy: All measurements within the inner and outer ring were read to the nearest 1/16 inch. All test measurements within the graduated mariotte tubes were read to the nearest millimeter. Test Results: The calculated rates from the double-ring infiltration testing I performed during this study are 0. 18, 0.16, and 006 inch/hour for Infiltration Test IT-1, IT-2, and 11-3, respectively. The relatively low infiltration rates obtained are likely due to clay I content of the artificial fill (IT-1) and the relative density and indurated nature of the bedrock materials (IT-2 and IT-3) onsite. As indicated previously, the field test data is provided I in Appendix E. I Conclusions and Recommendations-Infiltration As indicated above, the calculated infiltration rate of 0.18 inch/hour for th e a r t i f i c i a l f i l l a n d I between 0.16 and 0.06 inch/hour for the bedrock materials, ob t a i n e d a t a d e p t h o f approximately ±3 feet, may be utilized for design of the proposed deten t i o n s y s t e m s . I n addition to the above, an appropriate factor of safety, per the controll i n g a u t h o r i t i e s I requirements, should also be incorporated into the design calcul a t i o n s . T h e f o l l o w i n g comments and/or recommendations should also be conside r e d d u r i n g d e s i g n (structural and civil) and implementation of the proposed detention/infiltr a t i o n a n d / o r o t h e r BMP systems onsite: As with any BMP detention/infiltration device, localized ponding and gr o u n d w a t e r I seepage should be anticipated. Similarly, as with any BMP detention/infiltration device, proper mainte n a n c e a n d care will need to provided. Best management maintenance practices sh o u l d b e followed at all times, especially during inclement weather. Sh o u l d r e g u l a r inspection and/or required maintenance not be performed, the po t e n t i a l f o r I malfunctioning of the detention/infiltration systems will increase. I .Provisions for the maintenance of any siltation, debris, and/or overgrown V e g e t a t i o n (i.e., root systems) should be considered. An appropriate inspec t i o n a n d maintenance schedule will need to adopted and provided to all interes t e d / a f f e c t e d parties. Shap Homes Rancho Costera Carlsbad 09\6145a1 .stt W.O. 6145-Al-SC June 6, 2011 Page 11 Inc. Any proposed utility backfill materials located within the proposed area of the BMP may become saturated. This is due to the potential for piping, water migration, and/or seepage along the utility trench line backfill. If utility trenches cross and/or are proposed near the detention/infiltration systems, cut-off walls or other water barriers will likely need to be installed to mitigate the potential for piping and excess water entering the utility backfill materials. Any proposed footings and/or foundations should maintain a minimum of 1:1 horizontal to vertical (h-.v) distance from the base of the footing and/or foundation to any adjacent detention/infiltration system. If a 1:1 (h:v) distance cannot be maintained, a deepened footing and/or foundation will be required. I • The landscape architect should be notified of the location of the proposed detention/infiltration system(s). If landscaping is proposed over the detention/infiltration system, consideration should be given to the type of vegetation chosen and their potential effect upon subsurface improvements (i.e., some trees/shrubs will have an effect on subsurface improvements with their extensive root systems). The potential for surface flooding, in the case of detention/infiltration system blockage, should be evaluated by the design engineer. As the infiltration testing conducted for this study is specific to the anticipated nature of the artificial fill and bedrock materials encountered onsite, any changes to the design of the BMP's and/or estimated size or depth of the system, should be reviewed by this office. Depending upon the nature of any changes, proposed depth of the systems, and the requirements of the reviewing entity, additional infiltration testing may be warranted. Final grading and improvement plans, as well as structural foundation plans, should be submitted to this office for review and comment, as they become available, to minimize any misunderstandings between the preliminary recommendations presented herein. If project designs are found to differ substantially from those stated herein, appropriate recommendations would be offered at that time. PRELIMINARY CONCLUSIONS AND RECOMMENDATIONS IGeneral I The additional recommendations presented herein consider the additional information and findings obtained during this supplemental evaluation and the conclusions and recommendations presented in GSI (2010). Unless specifically superceded in the test of this report, the conclusions and recommendations presented in GSI (2010) remain valid and applicable. This report should be utilized on conjunction with GSI (2010) when IShapell Homes W.O. 6145-Al-SC Rancho Costera Carlsbad June 6, 2011 i FIe:e\,wpg\5100\6145a1 .stl Page 12 GeoSoil. hw. rZ1C 2 £XCOZ7' 1.6 Infiltration and Runoff AJA j 4 Infiltration of water through soil can reduce the amount of water that reaches stormwater management systems, filter pollutants and contaminants from the water, and recharge the watershed. The USDA Natural Resources Conservation Service (NRCS; formerly the Soil Conservation Service [SCS]), classifies a soil's infiltration characteristics into four Hydrologic Soil Groups (HSG): Group A: Low runoff potential. Soils having high infiltration rates even when I thoroughly wetted and consisting chiefly of deep, well-drained sands or gravels. I Group B: Soils having moderate infiltration rates when thoroughly wetted and consisting chiefly of moderately deep to deep, moderately well- to well-drained sandy loam soils with moderately fine to moderately coarse textures. I Group C: Soils having slow infiltration rates when thoroughly wetted and consisting chiefly of silty-loam soils with a layer that impedes downward I movement of water, or soils with moderately fine to fine texture. Group D: High runoff potential. Soils having very slow infiltration rates when I thoroughly wetted and consisting chiefly of clay soils with a high swelling potential, soils with a permanent high water table, soils with a claypan or clay layer at or near the surface, and shallow soils over nearly impervious material. I Group A and B soils possess the greatest infiltration rates (unless soils are compacted during construction) and are generally best suited to stormwater infiltration. However, I the San Diego Area has a relatively high concentration of Group C and D soils, which possess lower infiltration rates that either limit the use of infiltration-based stormwater management systems or require soil amendments to assist infiltration systems. I For a specific site, the HSG designation can be obtained by referring to a local soil survey, by consulting the complete national listing given in NRCS, or by performing an I on-site investigation. Soil Survey maps can be obtained from local NRCS offices or on- line4 for use in estimating soil type. The NRCS maps are also available at the County of San Diego, Department of Public Works. Consideration should be given to the effects of I urbanization on the natural hydrologic soil group. If heavy equipment can be expected to compact the soil during construction or if grading will mix the surface and subsurface soils, appropriate changes should be made in the soil group selected (SD County I Hydrology Manual 2003). The table below presents soil infiltration rates for each soil group determined by I laboratory studies and measurements. Site designers should compare the design runoff volume with the available soil storage volume to determine if infiltration is feasible, and then use the infiltration rates to determine if the design runoff volume can I infiltrate within a reasonable time (generally 24 to 48 hours). For sites with Group C and I ' http://websoilsurvey.nrcs.usda.gov/app Guidelines for Determining Significance 6 Surface Water Quality I D soils, retention- and detention based strategies are often more feasible than infiltration designs. TABLE I TYPICAL SOIL INFILTRATION RATES. Soil Type Minimum Infiltration Rate (inches per hour) A 0.30 to 0.45 B 0.15to0.30 C 0.05to0.15 D 0to0.05 In general, absorption of surface runoff by clay soils is low and reached quickly, whereas in sandy soils a larger portion of the runoff infiltrates the land surface and recharges the underlying groundwater system, resulting in less runoff. 1.7 Beneficial Uses of Water Beneficial uses are defined as, "uses of water necessary for the survival or well being of people, plants and wildlife." In San Diego County, residents, visitors and nature rely on the region's water resources to provide beneficial uses such as ensuring a clean and available drinking water supply, supporting agricultural, commercial, industrial, recreational, residential, and military uses, and supporting wildlife and habitat. The State Water Resources Control Board (SWRCB) has adopted a uniform list and description of beneficial uses to be applied throughout all basins of the State (Attachment B). These uses of water serve to promote the tangible and intangible economic, social and environmental goals identified in the Water Quality Control Plan for the San Diego Basin (9) prepared by the RWQCB (www.swrcb.caqov/rwgcb9/proqrams/basinplan.html). 1.8 Stormwater Drainage Systems I Within urban areas stormwater and sewage systems run parallel but are not combined. A vast amount of the unincorporated San Diego County is rural land that does not support or require stormwater drainage facilities. In contrast, most urban areas within I unincorporated San Diego County have a range of stormwater drainage facilities, all of which will continue to be improved as new discretionary projects are constructed. Collectively, stormwater drainage facilities make up a stormwater conveyance system. A stormwater conveyance system as defined by the County of San Diego Watershed Protection, Stormwater Management, and Discharge Control Ordinance, "means private and public drainage facilities other than sanitary sewers within the unincorporated areas of San Diego County by which urban run-off may be conveyed to receiving waters, and includes but is not limited to roads, streets, constructed channels, aqueducts, storm drain, pipes, street gutters, inlets to storm drains or pipes, and catch basins." Guidelines for Determining Significance 7 Surface Water Quality LI I I Li I I I I I I I I I I I I I I I LI I I Li' I I i I I Li I LI I I I I HYDROMODIFICATION SCREENING 0' I RANCHO COSTERA (ROBERTSON RANCH PLANNING AREAS 1-11, 13, & 23A-C) I AND I EL CAMINO REAL WIDENING I I June 19, 2013 I I I 1 Wayne W. Chang, MS, PE 46548 Cbangflw Civil Engineering Hydrology' Hydraulics Sedimentation P.O. Box 9496 Rancho Santa Fe, CA 92067 (858) 692-0760 I I I I I 1 I I I I I I I I I I I I I I I I I I I I -TABLE OF CONTENTS - Introduction................... Domain of Analysis...... Initial Desktop Analysis Field Screening............. Conclusion.................... Figures........................... APPENDICES SCCWRP Initial Desktop Analysis SCCWRP Field Screening Data MAP POCKET Study Area Exhibit Rancho Costera Drainage Study - Proposed Condition Work Map 1 3 6 7 12 13 ( OF I MARCOS 1 I INTRODUCTION The City of Carlsbad's January 14, 2011, Standard Urban Storm Water. Management Plan (SUSMP) outlines low flow thresholds for hydromodification analyses. The thresholds are based on a percentage of the pre-project 2-year flow (Q2), i.e., 0. 1Q (low flow threshold and high susceptibility to erosion), 0.3Q2 (medium flow threshold and medium susceptibility to erosion), or 0.5Q2 (high flow threshold and low susceptibility to erosion). A threshold of 0. 1Q2 represents a downstream receiving conveyance system with a high susceptibility to erosion. This is the default value used for hydrornodification analyses and will result in the most conservative (greatest) on-site facility sizing. A threshold of 0.3Q2 or 0.5Q2 represents downstream receiving conveyance systems with a medium or low susceptibility to erosion, respectively. In order to qualify for a medium or low susceptibility rating, a project must perform a channel screening analysis based on a "hydromodification screening tool" procedure developed by the Southern California Coastal Water Research Project (SCCWRP). The SCCWRP results are compared with the critical shear stress calculator results from the County of San Diego's BMP Sizing Calculator to establish the appropriate susceptibility threshold of low, medium, or high. I I I I I I I i I I I I I I Vicinity Map This report provides hydrornodification screening analyses for the Rancho Costera project (Vesting Tentative Map for Planning Areas 1-11, 13, and 23 A-C of the Robertson Ranch Master 1 L I I I Plan) and the adjacent El Camino Real widening project. Both projects are being designed by O'Day Consultants, Inc. (O'Day). Rancho Costera is located south of Calavera Hills Unit 1 (CT 76-12), west of Tamarack Avenue, and north of El Camino Real (see the Vicinity Map and the Study Area Exhibit in the map pocket). The El Camino Real widening is along the south side of Rancho Costera and will extend from Tamarack Avenue on the west to Cannon Road on the east. The Rancho Costera site is currently undeveloped and supports agricultural uses. The proposed site development varies by planning area (PA): PA 1 and 23A-C are designated as open space; PA 2 is a community facility site; PA 3, 5, 6, 9 and 10 are single-family residential developments; PA 4 is for community recreation, PA 7 and 8 are multi-family residential; and PA 11 is designated village center/commercial. Both projects are subject to hydromodification requirements because they are priority development projects. A variety of best management practices (bioretention basins, bioswales, etc.) will be incorporated throughout the projects to treat runoff from the development areas. Under pre-project conditions, storm runoff from the Rancho Costera site generally flows towards the south and occurs as sheet flow over the natural ground or as surface flow within natural drainage courses. The majority of this runoff is conveyed to an existing double 87foot by 4-foot reinforced concrete box culvert (RCB) under El Camino Real east of Kelly Drive or to an existing 8-foot by 8-foot RCB under El Camino Real west of Cannon Road. Some of the runoff will also flow onto El Camino Real where it will be collected by public storm drain systems along with the roadway runoff. The runoff from all of these areas is ultimately conveyed to Agua Hedionda Creek, which outlets into the Agua Hedionda Lagoon and then the Pacific Ocean. Under post-project conditions, proposed storm drain systems will be constructed to serve Rancho Costera and the existing El Camino Real storm drain system will be altered to accommodate the widening. However, the storm runoff will continue to be conveyed to Agua Hedionda Creek/Lagoon and the Pacific Ocean. The SCCWRP screening tool requires both office and field work to establish the vertical and lateral susceptibility of a natural downstream receiving channel to erosion. In this case, there are multiple natural downstream receiving channels near the easterly portion of the site and one natural receiving channel along the westerly portion of the site (see the Study Area Exhibit in the map pocket). The easterly natural channels confluence then flow to Agua Hedionda Creek, while the westerly natural channel flows into the Kelly Drive concrete-lined trapezoidal channel, which discharges to Agua Hedionda Creek. The vertical and lateral assessments are performed independently of each other although the lateral results can be affected by the vertical rating. A screening analysis was performed to assess the low flow threshold for the project's points of compliance, which are at each of the storm drain outlets into the natural channels. The initial step in performing the SCCWRP screening analysis is to establish the domain of analysis and the study reaches within the domain. This is followed by office and field components of the screening tool along with the associated analyses and results. The following sections cover these procedures in sequence. I I 1 I I I I U I I I I I F 7 I H I I DOMAIN OF ANALYSIS SCCWRP defines an upstream and downstream domain of analysis, which establish the study I limits. The County of San Diego's HMP specifies the downstream domain of analysis based on the SCCWRP criteria. The HMP indicates that the downstream domain is the first point where one of these is reached: at least one reach downstream of the first grade control point tidal backwater/lentic waterbody I.. equal order tributary accumulation of 50 percent drainage area for stream systems or 100 percent drainage area I for urban conveyance systems (storm drains, hardened channels, etc.) The upstream limit is defined as: I . proceed upstream for 20 channel top widths or to the first grade control point, whichever comes first. Identify hard points that can check headward migration and evidence of I active headcutting. SCCWRP defines the maximum spatial unit, or reach (a reach is circa 20 channel widths), for assigning a susceptibility rating within the domain of analysis to be 200 meters (656 feet). If the I domain of analysis is greater than 200 meters, the study area should be subdivided into smaller reaches of less than 200 meters for analysis. Most of the units in the HMP's SCCWRP analysis are metric. Metric units are used in this report only where given so in the HMP. Otherwise I English units are used. Downstream Domain ofAnalvsis I The downstream domain of analysis for a study area is determined by assessing and comparing the four bullet items above. As discussed in the Introduction, the project has a point of compliance (POC) at each of the storm drain outlets into a natural channel. In this case, there are I natural channels along the easterly and westerly portions of the site. Therefore, a downstream domain of analysis location will be selected below the downstream-most POC in both the easterly and the westerly channels. I The Study Area Exhibit shows several proposed storm drain outfalls into natural channels along the easterly portion of the site. These channels ultimately confluence upstream of El Camino I Real and flow to Agua Hedionda Creek south of El Camino Real. Some of the outfalls discharge at essentially the same location along a natural channel, so these form a single POC. The total number of POCs into the easterly channels is twelve (labeled A through L on the Study Area I Exhibit). The downstream-most POC within the easterly channels is POC L. The Study Area Exhibit shows four POCs (labeled M through F) within the natural channel along the westerly portion of the site. The downstream-most POC along this channel is POC P. I Therefore, downstream domain of analysis locations will be determined below POC L to the east and POC P to the west, and were assessed as follows. I I I I Per the first bullet item, the first permanent grade control point was located below POC L and POC P through a site investigation and review of aerial photographs. The waterbodies below POC L are Agua Hedionda Creek, Agua Hedionda Lagoon, and the Pacific Ocean. There are no permanent grade controls within these waterbodies below POL L, so this first criteria does not apply for POC L. For POC P, the natural receiving watercourse continues for over 1,000 feet, where it becomes the concrete-lined Kelly Drive trapezoidal channel. The Kelly Drive channel was recently repaired by the City of Carlsbad. Chang Consultants was under contract with Clayton Dobbs and Sherri I Howard at the City and assisted in obtaining the resource agency permits for the repairs. Since the channel is concrete and a primary public drainage facility, it is considered a permanent grade control. Therefore, the upper end of the Kelly Drive channel is the first permanent grade control I below POC P. The second bullet item is the tidal backwater or lentic (standing or still water such as ponds, pools, marshes, lakes, etc.) waterbody location. The nearest significant tidal backwater or lentic waterbody is for POC L and P is Agua Hedionda Lagoon. From Google Earth, the upstream extent of the lagoon is over 4,500 feet downstream of POC P. For POC L, the lagoon is I downstream of the Kelly Drive channel permanent grade control, so the lagoon will not govern for establishing the downstream domain of analysis location. I The final two bullet items are based on 50 and 100 percent tributary drainage areas (in this case, the channels are in urban areas, so the 100 percent criteria will be used). The natural channel below POC L confluences with Agua Hedionda Creek approximately 220 feet below POC L. I The overall area tributary to POC L covers approximately 5.11 square miles according to a 2008 Letter of Map Revision Request for Robertson Ranch by Chang Consultants. In comparison, FEMA's May 16, 2012, Flood Insurance Study indicates that the Agua Hedionda Creek I watershed covers 23.8 square miles at El Camino Real (see Appendix A for excerpts from both reports). This information shows that the Aqua Hedionda Creek tributary drainage area is much greater than 100 percent of the POC L drainage area. In addition, for POC P, a 100 percent larger I drainage area occurs where the Kelly Drive channel confluences with Agua Hedionda Creek. Therefore, for both POCs the tributary area criteria is met where their downstream channels confluence with Agua Hedionda Creek. I Based on the above information, the downstream domain of analysis below POC L occurs at the confluence with Agua Hedionda Creek, which is approximately 220 feet downstream of POC L. I There is no permanent grade control associated with POC L and the tidal backwater is several thousand feet further downstream of the confluence. The downstream domain of analysis for the natural channel tributary to POC P is at the I permanent grade control created at the upper end of the Kelly Drive concrete-lined channel. The tidal backwater and 100 percent tributary area are further downstream of the Kelly Drive channel. Per the first bullet item, the downstream domain of analysis is one reach below the I grade control point. As outlined above, a reach is not to exceed 200 meters (656 feet). The concrete-lined channel is longer than 656 feet, so the reach will be within the non-erodible U I I I I channel. Therefore, the downstream domain of analysis for the study reach associated with POC P occurs at the upper end of the Kelly Drive channel. I Upstream Domain ofAnalvsis The upstream domain of analysis must be established for the easterly and westerly natural channels. Along the easterly side, there are three upstream-most POCs: POC A, POC B, and I POC H (see the Study Area Exhibit). The outlet of each of these is essentially at the upstream end of the receiving natural channel. Since the area upstream of these three POCs is not an erodible channel, each POC establishes an upstream domain of analysis location. I Along the westerly side, the upstream-most POC is POC M, and the watercourse above POC M begins at the southerly edge of Tamarack Avenue approximately 290 feet above POC M. Therefore, the upstream domain of analysis location for the westerly natural channel is at the I southerly edge of Tamarack Avenue. Study Reaches within Domain ofAnalysis I The total domain of analysis (or overall study reach) within the easterly area extends from the three upstream POCs to Agua Hedionda Creek south of El Canino Real. The total domain of analysis for the various natural channels within the westerly area covers approximately 6,241 I feet (1,902 meters). The domain of analysis was subdivided into eight natural study reaches with similar characteristics (see the Study Area Exhibit). Reach El extends 2,700 feet (823 meters) from the upstream domain of analysis location at POC A down to POC F, which is at a channel I confluence. Reach E2 extends 1,253 feet (382 meters) from the upstream domain of analysis location at POC B to POC C. Reach E3 extends 244 feet (74 meters) from POC C to POC D. POC D and E are at the upstream and downstream ends of the proposed Street E culvert crossing I of the channel. Reach E4 extends 687 feet (209 meters) from POC E to the channel confluence at POC F. Reach ES extends 250 feet (76 meters) from POC F to an existing concrete-lined access road crossing the natural channel. Reach E6 extends 284 feet (87 meters) from the access road to I POC G, which is located at the upstream end of the existing 8-foot by 8-foot RCBs under El Camino Real. Reach E7 extends 603 feet (184 meters) from the upstream domain of analysis location at POC H to POC G. Reach E8 extends 220 feet (67 meters) from POC L at the I downstream end of the 8-foot by 8-foot RCBs under El Camino Real to the downstream domain of analysis location at the confluence with Agua Hedionda Creek. I The total domain of analysis for the westerly area covers approximately 2,546 feet (776 meters). Reach WI begins at the upstream domain of analysis location on the south side of Tamarack Avenue and extends 290 feet (88 meters) to the upstream end of the proposed Street J access road from Tamarack Avenue. Street J crosses the stream channel and will contain a culvert to convey the stream flow through the roadway embankment. Reach W2 extends 309 feet (94 meters) from POC M at the lower end of the proposed Street J culvert to POC N. Reach W3 I extends 940 feet (287 meters) from POC N to POC 0, which is located at the upstream end of the existing double 8-foot by 4-foot RCBs under El Camino Real. POC P is at the downstream end of the existing double 8-foot by 4-foot RCBs under El Camino Real. Reach W4 extends 1,007 feet (307 meters) from POC P to the downstream domain of analysis location at the upper I end of the concrete-lined Kelly Drive channel. I I I I Several of the study reaches are longer than the 656 feet (200 meters) maximum reach length specified by SCCWRP. Review of topographic mapping, aerial photographs, and field conditions reveals that the physical (channel geometry and longitudinal slope), vegetative, hydraulic, and soil conditions within each of the reaches are relatively uniform. Subdividing the reaches into smaller subreaches of less than 656 feet will not yield significantly varying results within a reach. Although the screening tool was applied across the entire length of each study reach, the results will be similar for shorter subreaches within each reach. INITIAL DESKTOP ANALYSIS After the domain of analysis is established, SCCWRP requires an "initial desktop analysis" that involves office work. The initial desktop analysis establishes the watershed area, mean annual precipitation, valley slope, and valley width. These terms are defined in Form 1, which is included in Appendix A. SCCWRP recommends the use of National Elevation Data (NED) to determine the watershed area, valley slope, and valley width. The NED data is similar to USGS mapping. For this report, O'Day's proposed condition hydrology data was used, where available, to identify the drainage areas, which is more accurate than using NED data. The relevant pages from O'Day's hydrology analyses are included in Appendix A and their workmap is included in the map pocket. O'Day's analyses do not provide drainage areas for Reach E7, E8, or W4, so these were obtained as follows. Chang Consultants prepared a 2008 Letter of Map Revision Request Jbr Robertson's Ranch that delineated the tributary drainage areas to Reach E7 and E8, so the LOMIR data was used (see Appendix A for excerpts). For Reach W4, O'Day's analyses determined the tributary area at the upper end of the reach. The additional area tributary to the lower end of Reach W4 was delineated from the project's topographic mapping to determine the total drainage area tributary to Reach W4. The delineation is included on the Study Area Exhibit. The mean annual precipitation is provided by the County of San Diego's BMP Sizing Calculator (see Appendix A) and is 13.3 inches. The valley slopes of each study reach were determined from the 2-foot contour interval mapping I prepared for the project, where available, and the City's 2-foot contour interval topographic mapping for a small area at the east. The valley slope is the longitudinal slope of the channel bed along the flow line, so it is determined by dividing the elevation difference within a reach by the flow path. The 2-foot contour mapping sources were used because they will provide more I precise results than NED data. I The valley width is the bottom width of the main creek channel. The average valley width within each reach was estimated from the 2-foot contour interval topographic mapping, field observations, and review of aerial photographs. The valley slope and valley width for each reach I are summarized in Table 1. These values were input to a spreadsheet to calculate the simulated peak flow, screening index, and valley width index outlined in Form 1. The input data and results are tabulated in Appendix A. This completes the initial desktop analysis. I I I I I I I I I I U Reach I Tributary Area, sq. mi. r Valley Slope, mlm[ Valley Width, In El 1 0.2400 [ 0.0289 6.1 _E21 0.0731 0.0551 F 1.5 [_E3 0.0732 0.0369 1.5 E4 0.1272 [ 0.0247 8.5 E5 03963 [ 00092 110 E6 F 0.3964 1 0.0088 - 4.6 _E71 4.6800 [ 0.0060 16.8 E8 1 51100 J00091 259 _W11 0.0054 [0.0448 2.4 W2 0.8078 1 0.0191 6.1 W3 1.1157-1 0.0127 17.7 IW4 12688 F 00183 - 49 * Table 1. Summary of Valley Slope and Valley Width FIELD SCREENING I After the initial desktop analysis is complete, a field assessment must be performed. The field assessment is used to establish a natural channel's vertical and lateral susceptibility to erosion. I SCCWRP states that although they are admittedly linked, vertical and lateral susceptibility are assessed separately for several reasons. First, vertical and lateral responses are primarily controlled by different types of resistance, which, when assessed separately, may improve ease I of use and lead to increased repeatability compared to an integrated, cross-dimensional assessment. Second, the mechanistic differences between vertical and lateral responses point to different modeling tools and potentially different management strategies. Having separate screening ratings may better direct users and managers to the most appropriate tools for I subsequent analyses. The field screening tool uses combinations of decision trees and checklists. Decision trees are I typically used when a question can be answered fairly definitively and/or quantitatively (e.g., d50 < 16 mm). Checklists are used where answers are relatively qualitative (e.g., the condition of a grade control). Low, medium, high, and very high ratings are applied separately to the vertical I and lateral analyses. When the vertical and lateral analyses return divergent values, the most conservative value shall be selected as the flow threshold for the hydrornodification analyses. I Visual observation reveals that most of the study reaches contain a moderate to densely vegetated channel (see the figures following the report text). The vegetative density extends relatively uniformly across the channel bottom and sides. Due to the vegetative cover, riprap I energy dissipaters at each POC, and lack of significant erosion noted during the site investigation, the vertical and lateral stability was anticipated to have a limited susceptibility to erosion. I I H Li LI I L I I I Vertical Stability The purpose of the vertical stability decision tree (Figure 6-4 in the County of San Diego HMP) is to assess the state of the channel bed with a particular focus on the risk of incision (i.e., down cutting). The decision tree is included in Figure 30. The first step is to assess the channel bed resistance. There are three categories defined as follows: Labile Bed - sand-dominated bed, little resistant substrate. Transitional/Intermediate Bed - bed typically characterized by gravel/small cobble, Intermediate level of resistance of the substrate and uncertain potential for armoring. Threshold Bed (Coarse/Armored Bed) - armored with large cobbles or larger bed material or highly-resistant bed substrate (i.e., bedrock). Channel bed resistance is a function of the bed material and vegetation. The figures after this report text contain photographs of the natural channels in each study reach. A site investigation and the figures indicate that the vegetative cover throughout each natural channel within Reaches El through E4, E8, and WI through W4 is mature, dense, and fairly uniform (see Figures 1 through 10 and 17 through 26). The vegetation in some areas is so dense that the channel was either difficult to access or not possible to access at all unless the vegetation is trimmed. The vegetation consists of a variety of mature grasses, reeds, shrubs, and trees. Vegetation prevents bed incision because its root structure binds soil and because the aboveground vegetative growth reduces flow velocities. Table 5-13 from the County of San Diego's Drainage Design Manual outlines maximum permissible velocities for various channel linings (see Table 5-13 in Appendix B). Maximum permissible velocity is defined in the manual as the velocity below which a channel section will remain stable, i.e., not erode. Table 5-13 indicates that a fully-lined channel with unreinforced vegetation has a maximum permissible velocity of 5 feet per second (fps). Due to the dense cover and mature vegetation, the permissible velocity when erosion can initiate is likely greater than 5 fps in most of the natural channel areas. Table 5-13 indicates that 5 fps is equivalent to an unvegetated channel containing cobbles (grain size from 64 to 256 mm) and shingles (rounded cobbles). In comparison, coarse gravel (19 to 75 mm) has a maximum permissible velocity of 4 fps. Based on this information, the uniformly vegetated natural canyons in Reaches El through E4, E8, and Wi through W4 has an equivalent grain size of at least 64 mm, which is comparable to a transitional/intermediate bed. Figures 11 through 16 show that Reaches ES through E7 contain sparser vegetation than the other reaches. Therefore, a relationship between vegetative cover and grain size is not applicable, and pebble count must be performed. Figures 15 through 17 contain photographs of the typical bed material within these three study reaches. A gravelometer is included in the photographs for reference. Each square on the gravelometer indicates grain size in millimeters (the squares range from 2 mm to 180 mm). A pebble count was performed (see results in Appendix A) that determined the median (d50) bed material size to be 11 millimeters (mm) in Reaches ES, E6, and E7. I Li I I I I I Li Li U I I I I I I I I I In addition to the material size, there are several factors that establish the erodibility of a channel such as the flow rate (i.e., size of the tributary area), grade controls, channel slope, vegetative cover, channel planfonn, etc. The Introduction of the SCCWRP 1-lydromodification Screening I Tools: Field Manual identifies several of these factors. When multiple factors influence erodibility, it is appropriate to perform the more detailed SCCWRP analysis, which is to analyze a channel according to SCCWRP's transitional/intermediate bed procedure. This requires the I most rigorous steps and will generate the appropriate results given the range of factors that define erodibility. The transitional/ intermediate bed procedure takes into account that bed material may fall within the labile category (the bed material size is used in SCCWRP's Form 3 I Figure 4), but other factors may trend towards a less erodible condition. Dr. Eric Stein from SCCWRP, who co-authored the 1-lydromodification Screening Tools: Field Manual in the Final Hydromodification Management Plan (HMP), indicated that it would be appropriate to analyze channels with multiple factors that impact erodibility using the transitional/intermediate bed I procedure. Consequently, this procedure was used to produce more accurate results for each study reach. I Transitional/intermediate beds cover a wide susceptibility/potential response range and need to be assessed in greater detail to develop a weight of evidence for the appropriate screening rating. The three primary risk factors used to assess vertical susceptibility for channels with I transitional/intermediate bed materials are: I 1. Armoring potential - three states (Checklist 1) 2. Grade control - three states (Checklist 2) I 3. Proximity to regionally-calibrated incision/braiding threshold (Mobility Index Threshold - Probability Diagram) I These three risk factors are assessed using checklists and a diagram (see Appendix B), and the results of each are combined to provide a final vertical susceptibility rating for the intermediate/transitional bed-material group. Each checklist and diagram contains a Category A, I B, or C rating. Category A is the most resistant to vertical changes while Category C is the most susceptible. I Checklist 1 determines armoring potential of the channel bed. The channel bed along each of the twelve reaches is within category B, which represents intermediate bed material within unknown annoring potential due to a surface veneer and dense vegetation. The soil was probed and I penetration was relatively difficult through the underlying layer of each reach. Due to the dense vegetative growth in some reaches, the armoring potential could have been rated higher in those reaches, but Category B was conservatively (i.e., more potential for channel incision) chosen. I Checklist 2 determines grade control characteristics of the channel bed. SCCWRP states that grade controls can be natural. Examples are vegetation or confluences with a larger waterbody. As indicated above and verified with photographs, Reaches El through E4, E8, and WI through I W4 contain dense vegetation (see the figures). The plant roots and tree trunks serve as a natural grade control. The spacing of these is much closer than the 50 meters or 2/Sw values identified in I 9 I I I the checklist. Further evidence of the effectiveness of the natural grade controls is the absence of headcutting and mass wasting (large vertical erosion of a channel bank). Based on this information, Reaches El through E4, E8, and Wi through W4 are within Category A on Checklist 2. Reaches E5 through E7 do not contain dense vegetation. However, each of these reaches has a grade control at their downstream end. For Reach E5, the existing concrete-lined access road crossing of the natural channel (see Figure 13) is a permanent grade control. For Reaches E6 and E7, the existing 8-foot by 8-foot RCB under El Camino Real is a permanent grade control (see Study Area Exhibit). Table 2 summarizes the length, 2IS, and 4/Sw values for each of these reaches. Table 2 shows that for each reach, the reach length is less than the 2IS value (and naturally also less than 4IS). Therefore, the grade control spacing in each of the three reaches is less than 2IS and each reach is within Category A on Checklist 2. Study Reach Reach Length, ft 2IS, ft 4/Sw, ft E5 250 713 1,426 E6 284 745 1,491 E7 603 1 1,099 1 2,198 Table 2. Grade Control Spacing Data The Screening Index Threshold is a probability diagram that depicts the risk of incising or braiding based on the potential stream power of the valley relative to the median particle diameter. The threshold is based on regional data from Dr. Howard Chang of Chang Consultants and others. The probability diagram is based on d50 as well as the Screening Index determined in the initial desktop analysis (see Appendix A). d50 is derived from field conditions. As discussed above, the equivalent grain size for the densely-vegetated channels in Reaches El through E4, E8, and WI through W4 is at least 64 mm. The Screening Index Threshold diagram shows that the 50 percent probability of incising or braiding for a d50 of 64 mm has an index of at least 0.101 (in red rectangle on diagram). The Screening Index for these nine reaches calculated in Appendix A varies from 0.009 to 0.039. Since each reach's Screening Index value is less than the 50 percent value, Reaches El through E4, E8, and WI through W4 fall within Category A. For Reaches E5 through E7, their D50 value was entered onto the Screening Index Threshold I graph. As mentioned above, a pebble count determined that the D50 for each of these reaches is 11 mm. Plotting i 1 mm on the graph corresponds to a 50 percent Screening Index value of 0.03 8. The Screening Index calculated in Appendix A for the three reaches varies from 0.011 to ' 0.023. Since each reach's Screening Index value is less than the 50 percent value, Reaches E5, E6, and E7 fall within Category A. The overall vertical rating is determined from the Checklist 1, Checklist 2, and Mobility Index I Threshold results. The scoring is based on the following values: I Category A = 3, Category B = 6, Category C = 9 The vertical rating score for each of the twelve reaches is based on these values and the equation: 1 10 I I I I I 11' I I I I L] I I J I Vertical Rating = [(armoring x grade control)"' x screening index score]"' = [(6x 3)1/2 x 3]1' '2 (Note: each of the twelve reaches has similar values) I =3.6 Since the vertical rating is less than 4.5, each reach has a low vertical susceptibility to erosion. I Lateral Stability The purpose of the lateral decision tree (Figure 6-5 from County of San Diego HMP included in I Figure 31) is to assess the state of the channel banks with a focus on the risk of widening. Channels can widen from either bank failure or through fluvial processes such as chute cutoffs, avulsions, and braiding. Widening through fluvial avulsions/active braiding is a relatively straightforward observation. If braiding is not already occurring, the next logical step is to assess I the condition of the banks. Banks fail through a variety of mechanisms; however, one of the most important distinctions is whether they fail in mass (as many particles) or by fluvial detachment of individual particles. Although much research is dedicated to the combined effects of weakening, U fluvial erosion, and mass failure, SCCWRP found it valuable to segregate bank types based on the inference of the dominant failure mechanism (as the management approach may vary based on the dominant failure mechanism). A decision tree (Form 4 in Appendix B) is used in I conducting the lateral susceptibility assessment. Definitions and photographic examples are also provided below for terms used in the lateral susceptibility assessment. I The first step in the decision tree is to determine if lateral adjustments are occurring. The adjustments can take the fonn of extensive mass wasting (greater than 50 percent of the banks are exhibiting planar, slab, or rotational failures and/or scalloping, undermining, and/or tension I cracks). The adjustments can also involve extensive fluvial erosion (significant and frequent bank cuts on over 50 percent of the banks). Neither mass wasting nor extensive fluvial erosion was evident within any of the reaches during a field investigation. The banks are intact in the I photographs included in the figures. Due to the dense vegetation in most areas, photographs representative of the banks were difficult to take. Nonetheless, the dense vegetation supports the absence of large lateral adjustments. I The next step in the Form 4 decision tree is to assess the consolidation of the bank material. The banks were moderate to well-consolidated. This determination was made because the banks were difficult to penetrate with a probe. In addition, the banks showed limited evidence of crumbling I and were composed of well-packed particles. I Form 6 (see Appendix B) is used to assess the probability of mass wasting. Form 6 identifies a 10, 50, and 90 percent probability based on the bank angle and bank height. The 2-foot contour interval topographic mapping indicates that the average natural bank angle is no greater than 2 to I i (horizontal to vertical) or 26.6 degrees in any of the reaches. Form 6 shows that the probably of mass wasting and bank failure has less than 10 percent risk for a 26.6 degree bank angle or less regardless of the bank height. I The final two steps in the Form 4 decision tree are based on the braiding risk determined from the vertical rating as well as the Valley Width Index (VWI) calculated in Appendix A. If the U 11 I I I I vertical rating is high, the braiding risk is considered to be greater than 50 percent. Excessive braiding can lead to lateral bank failure. For all 12 study reaches, the vertical rating is low, so the braiding risk is less than 50 percent. Furthermore, a VWJ greater than 2 represents channels unconfined by bedrock or hillslope and, hence, subject to lateral migration. The VWI I calculations in the spreadsheet in Appendix A show that the VWI for each reach is less than 2. From the above steps, the lateral susceptibility rating is low for each of the twelve study reaches (red circles are included on the Form 4: Lateral Susceptibility Field Sheet decision tree in Appendix B showing the decision path). A review of aerial photographs confirms a lack of braiding or lateral migration throughout the natural channels. I CONCLUSION The SCCWRP channel screening tools were used to assess the downstream channel susceptibility for the Rancho Costera and associated El Camino Real Widening projects being I designed by O'Day Consultants, Inc. The project runoff will ultimately be collected by a series of proposed and/or existing storm drain systems that outlet into unnamed natural channels at various locations along the easterly and westerly portions of the developments. Each outlet is a I point of compliance. Based on the points of compliance, the unnamed natural channels were assessed from the upstream-most POCs to either the confluence with Agua Hedionda Creek or the concrete-lined Kelly Drive trapezoidal channel (domain of analysis). The assessment was I performed based on office analyses and field work. The results indicate a low susceptibility for vertical and lateral channel erosion for the entire study area. ' The HMP requires that these results be compared with the critical stress calculator results incorporated in the County of San Diego's BMP Sizing Calculator. The BMP Sizing Calculator critical stress results are included in Appendix B for all twelve reaches. Based on these values, I the critical stress results returned a low susceptibility to erosion. Therefore, the SCCWRP analyses and critical stress calculator demonstrate that the project can be designed assuming a low susceptibility, i.e., 0.5Q2. I The SCCWRP results are consistent with the physical condition of the natural channel within the domain of analysis, which is moderately to densely-vegetated throughout. None of the twelve study reaches exhibit signs of extensive, ongoing erosion. I I I I I 12 r 4 4 •2 -t 151 ; 2 - 2 pper End ': Fiur 2. Looking Liptreani tos%ards Reach El from Midpoint 13 I- ru .. Li . 114mlistre"lln km arcs Peach "A Iturn Nt dpoiiit - +- . •-. - .-- +- +.... - -+-- - - .. - -• cs .+? 14 1 - r Y, 4ri- y-. -- — - $ - - -V - -- -V-V - A c -: - - - V.- F i ti i.e 4. LooUn Upstream I o' i rtls Reach F I from Lower 'i- End 5- - - - - .- - - M -i 41 4\ - - -- ;c - -. )• -W. 44 it* 4 J p - - - r - , - - -, --.- - Ia )- :- - j. - i igure S L joking Dovuisireaw t)wal'dS Reach E2 from Upper End - - . -- - - -- I igui-e (. tuukiiig Upstream ii rtI' I' h 1-2 Itin \Iu1J).nllt i! IH Look- g DO II t euii Lovaru i2 I r An A MpAnt -. f :. ' • : • Wet FigLi e 8. .JOLiiI2 L j)stl1dflI tommids Reaches F 2 and hi I u. 16 Figure 9. Looking LLa (cdy IoMwar- I acIi L4 1 Igu ic 10. Looking ( ptream towards Reach L4 I ruin Lii cu ruu 17 ;.At _ :ktl I FV 4 ly I- iguiu kol I I'ItI1i 14J ar(IS Reach tz I uin ( per 1 lid Iguic I .. L ooking I PStI1il1u LU%% ar(is 1(tacI I nJIII Lo er Li LI 18 -V V - lt V -V. V V • ft ' - 4 * 4/ * - V V Ak V W1, V D: * V V ; It V V -- • V V _ ViV ; 7 : . - P V V, VV-•: - V JV JV igu re 13. Looking Southe1rh 10 rds VC! V - V V V VVVV emw VV - V V4 -:VV V• V• :--;Vi: V •V !!V V;V : V • - V - - 4 V V 4 Ow V4 • ••V .4 V V VV.4 V - • - V - - VV 4 - - • - ** -V 'V - V •:V • VV;kv • V 4 -V •-• SV V •4 V V - V V -. f :.r-- -! Figure 14. Looking Upstream to ards R ah 10 from El Camino Real - '4.. ':•). Figure 15. Looking Downstream to%'ar(Is Reach E7 IFT)nI Upper Iiitl - 4 ..,-,. -jiI- -• A MI- : Figure 16, Looking \ 1% L o ard k 20 - - - - <-_ - -JQ c MIA 4Y { 1.gLILC 17. Looking Southeasterly tow ards Reach ES and Agi i Udiond. ( reek -is) nwin Opt 1 Fig I:'e IV. iooIing I. 1sLrea ards beach \ Iroiii LUvI Enu so 'Al loco, 2(. ioukiug itiisu tan u, Maua . i -y) t. 1ca h \\ 2 fivai io%eF E nd 1 - - I fll Awl I 22. LoKIg Doi streani ()vards Reach Wl i ruin I. per A 1 71 -A - - c 4 - ---- • -_,•' r- - ' -- il - ' If Figii re 24. Looking is ns I rani 10n !I i-us Li I A U Hn L pper Erbd 24 -, 4v At As -441 1 AW lot, 7 A 5k 9 AL Wk Mir 9 - - ON tt , V fr*9 9 - - - -J_ •;:-- 0 7 P . ii)ciis.e Vegetatioii within Middle of Reach W4 w&t461,6A 7Y aye Q -' - VAT W - - ; 9 9 V -9 Figure 2( Loikiiig L pstreana tuwards Rach W4 1roi Lower End at Concrete-Lined Fellv 14 Channel _,I r & • lometer NN ii h In R J NOV- j 4p , I ) I 'i k u-I- N Figure 28. Gravdometer witlAr Re tch E6 26 I I 28 IT Figure 6-4. SCCWRP Vertical Susceptibility Figure 30. SCCWRP Vertical Channel Susceptibility Matrix [I U I I I I I I I I I I I I I I I I I I I 1 I 1 I I I I I I I I I I I Lm LATIEKAL&ADJUSTABLO tovik OPAMOSOn in tnd C"On YES ARE LATERAL RAY ewfifl so, &w"lly YES ADJUSTMENTS WE V LIAIAL nnini$ri t, hin1 w t EHIIjN RJT CUTCFF FORMATIM, None% or ftwi mly funind io MD CHIGH Da anwt*Ects Z ALL USINt( 6 1RTA r'c' == >_EuT I Ccrwe I rI rtd toed Lu~ ria,-oded uriIdlrd 4mm AND 1iWI2 Fiktodaf I HI t Xu-m6,- Ow elf ft. ................. . .......... I ............. .......... ........ ................. BrtI Smiding risk rkn braiding I LOW &O HIGH MPD HtGH 3 rkcffl* 'fM$2 W1c2I VW2 - 4.,-.... .---.. 4. .4 ...4 . af 0-0 DKWon Figure 6-5 Laerai Channd Susceptibility Figure 31. SCCWRP Lateral Channel Susceptibility Matrix I I I APPENDIX& I SCCWRP INITIAL DESKTOP ANALYSIS I I I I I I I I I I 17 I I I I I I FORM 1: INITIAL DESKTOP ANALYSIS Complete all shaded sections. IF required at multiple locations, circle one of the following site types: Applicant Site I Upstream Extent I Downstream Extent Location: Latitude: 33.154 Longitude:: 1173040 Description (river name, crossing streets, etc.): Rancho Costera (north of El Camino Real between Tamarack Ave and Cannon Rd.) and El Camino Real widening. GIS Parameters: The International System of Units (SI) is used throughout the assessment as the field standard and for consistency with the broader scientific community. However, as the singular exception, US Customary units are used for contributing drainage area (A) and mean annual precipitation (P) to apply regional flow equations after the USGS. See SCCWRP Technical Report 607 for example measurements and Screening Tool Data Entry.xls" for automated calculations. Form I Table 1. Initial desktop analysis in GIS. Symbol Variable Description and Source Value A Area Contributing drainage area to screening location via published (mi) Hydrologic Unit Codes (HUCs) and/or :5 30 m National Elevation Data . . (NED), USGS seamless server ................................................................................................................................................................................................................................................................................ co 12 P Mean annual Area-weighted annual precipitation via USGS delineated polygons using O. precipitation records from 1900 to 1960 (which was more significant in hydrologic See attached (in) models than polygons delineated from shorter record lengths) Form 1 table S Valley slope Valley slope at site via NED, measured over a relatively homogenous on next page (m/m) valley segment as dictated by hillslope configuration, tributary for calculated confluences, etc., over a distance of up to —500 m or 10% of the main- values for each channel length from site to drainage divide .................................................................................................................................................... ................................reach 8- jj5 WV Valley width Valley bottom width at site between natural valley walls as dictated by (m) clear breaks in hilislope on NED raster, irrespective of potential armoring from floodplain encroachment, levees, etc. (imprecise measurements have negligible effect on rating in wide valleys where VWI is >> 2, as defined in lateral decision tree) Form I Tabl e 2. Simplif ied peak flo w, screening index, and valley width index. Values for this table should be calculated in the sequence shown in this table, using values from Form 1 Table 1. Symbol Dependent Variable Equation Required Units Value Qlocfs 10-yr peak flow (ft3/s) = 18.2 * A 0.87 * p0.77 A (mi2) P(in) See attached Qo 10-yr peak flow (m3/s) Qio = 0.0283 *Qlof, Q10, (ft3/s) Form 1 table INDEX 10-yr screening index (m15/s°5) INDEX Sv*Q10 O5 Sv(m/m) QIO (m3/s) on next page for calculated Wret Reference width (m) 0.438 Wret 6.99 * Q10 010 (m3/s) values for each VWI Valley width index (rn/rn) VWI = W/W1 W (m) Wrei (m) reach. (Sheet I of 1) B-3 I LI I [1 I I I I I I 11' H H n H I I I I - - - - - - - - - - - - - - - - - - - SCCWRP FORM 1 ANALYSES Area Mean Annual Precip. Valley Slope Valley Width 10-Year Flow 10-Year Flow Reach A, sq. mi. P1 inches Sv, rn/rn Wv, m QiOcfs, cfs Q10, crns El 0.2400 13.3 0.0289 6.1 39 1.1 E2 0.0731 13.3 0.0551 1.5 14 0.4 E3 0.0732 13.3 0.0369 1.5 14 0.4 E4 0.1272 13.3 0.0247 8.5 22 0.6 ES 0.3963 13.3 0.0092 11.0 60 1.7 E6 0.3964 13.3 0.0088 4.6 60 1.7 E7 4.6800 13.3 0.0060 16.8 511 14.5 ES 5.1100 13.3 0.0091 25.9 552 15.6 Wi 0.0054 13.3 0.0448 2.4 1 0.04 W2 0.8078 13.3 0.0191 6.1 111 3.1 W3 1.1157 13.3 0.0127 17.7 147 4.2 W4 1.2688 13.3 0.0183 4.9 164 4.6 10-Year Screening Index Reference Width Valley Width Index Reach INDEX Wref, m VWI, rn/rn El 0.030 7.3 0.84 E2 0.034 4.6 0.33 E3 0.023 4.6 0.33 E4 0.020 5.7 1.50 ES 0.012 8.8 1.25 E6 0.011 8.8 0.52 E7 0.023 22.5 0.74 E8 0.036 23.3 1.11 Wi 0.009 1.7 1.42 W2 0.034 11.5 0.53 W3 0.026 13.0 1.36 W4 0.039 13.7 0.36 - - - - - - - - - - - - - - - - - - - Li LiBasin U Manage Your Basins Create a new Basin by clicking the New button and scroll down to view entry Alternatively, select an existing Basin from table and view properties below. Click Edit button to change Basin properties then press Save to commit changes. 4J Description Rncho Costera&ECR Drainage Point of Compliance [vanous Storm Drain tutfalls Design Goal: E Treatment + Flow Control •jj Project Basin Area (ad: J Rainfall Basin: [5nside Mean Annual Precipitlon (in) I MEAN ANNUAL PRECIPITATION FROM COUNTY BMP SIZING CALCULATOR PEBBLE COUNT I 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 Reach E5 Diameter, mm 2 2 2 2 2 2.8 2.8 2.8 2.8 2.8 4 4 4 4 4 4 4 4 4 4 4 4 4 5.6 5.6 5.6 5.6 5.6 5.6 5.6 5.6 5.6 5.6 5.6 8 8 8 8 8 8 8 8 8 8 Reach E6 Diameter, mm 2 2 2 2 2 2 2 2 2 2.8 2.8 2.8 2.8 2.8 2.8 2.8 2.8 2.8 4 4 4 4 4 4 4 4 4 4 5.6 5.6 5.6 5.6 5.6 5.6 5.6 5.6 5.6 5.6 5.6 5.6 5.6 5.6 8 8 Reach El Diameter, mm 2 2 2 2 2 2 2 2 2.8 2.8 2.8 2.8 2.8 2.8 2.8 2.8 4 4 4 4 4 4 4 4 4 4 4 4 5.6 5.6 5.6 5.6 5.6 5.6 5.6 8 8 8 8 8 8 8 8 8 I I I I I I I 1 I I I I I I I I Reach E5 Diameter, mm Reach E6 Diameter, mm Reach E7 Diameter, mm 45 8 8 11 46 8 8 11 47 8 8 11 48 11 8 11 49 11 11 11 50 11 11 11 51 11 11 11 52 11 11 11 53 11 11 11 54 11 11 11 55 11 11 11 56 11 11 11 57 11 11 16 58 11 11 16 59 11 11 16 60 11 11 16 61 11 11 16 62 11 11 16 63 11 11 16 64 11 11 16 65 11 16 16 66 11 16 16 67 16 16 16 68 16 16 16 69 16 16 16 70 16 16 16 71 16 16 16 72 16 16 16 73 16 16 16 74 16 16 16 75 16 16 16 76 16 16 16 77 16 16 16 78 16 16 16 79 16 16 16 80 16 16 16 81 16 16 16 82 16 16 16 83 16 16 16 84 16 16 16 85 16 16 22.6 86 16 16 22.6 87 16 16 22.6 88 16 16 22.6 89 16 22.6 22.6 90 16 22.6 22.6 LI Li I I I I 91 92 93 94 95 96 97 98 99 100 Reach ES Diameter, mm 22.6 22.6 22.6 22.6 22.6 22.6 22.6 22.6 32 32 Reach E6 Diameter, mm 22.6 22.6 22.6 22.6 22.6 22.6 22.6 32 32 32 Reach El Diameter, mm 22.6 22.6 22.6 22.6 32 32 32 32 32 64 I I I I Li j I I I I I I Li I - - - - - - - - - - - - - - - - - - - EXCERPT FROM FEMA' MAY 16, 2012, "FLOOD INSURANCE STUDY, SAN DIEGO, COUNTY" SHOWING AGUA HEDIONDA CREEK DRAINAGE AREA TABLE 8: SUMMARY OF PEAK DISCHARGES Peak Discharges (cubic feet per second) Flooding Source and Location Drainage' Area 10% Annual- ' % Annuai- 1 Annual- 0.2% Annual- % mil). es Adobe Creek 2,200 Feet Upstream of Peet Lane 0.67 375 485 560 710 Agua 1-ledionda Creek At Confluence with Buena Creek 6.3 1,600 4,800 7,000 15,500 2,200 Feet Upstream of Rancho Carlsbad Drive 16.5 -- -- 7,810 -- Upstream of Calavera Creek 17.3 -- -- 8,080 At El Camino Real 23.8 -- -- 9,850 -- Alvarado Creek At Lake Shore Drive 4.6 1,200 2,000 2,300 3,000 At Interstate 8, Near Trailer Park 5.3 1,300 2,200 2,500 3,200 At interstate 8, Near Murray Boulevard 5.7 1,400 2,400 2,700 3,500 Upstream of Murray Creek 6.3 1,600 2,600 3,000 3,800 Downstream of Murray Creek 10.1 1,700 2,900 3,300 4,200 At Downstream Side of College Avenue 11.4 2,100 3,400 3,900 5,000 Upstream of Tributary Channel 12.1 2,300 3,700 4,300 5,400 Downstream of Tributary Channel 13.4 2,600 4,300 4,800 6,100 -- Data Not Available 68 EXCERPTS FROM O'DAY CONSULTANTS' "RANCHO COSTERA DRAINAGE STUDY". SEE MAP POCKET FOR WORK MAP. APPENDIX 6 100 Yr. Proposed Hydrologic Calculations Basin 'H' (See Exhibit 'K') 11 I Maximum flow rates at confluence using above data: 37.976 22.996 40.432 49.662 Area of streams before confluence: 5.550 1.210 2.000 26.600 Results of confluence: Total flow rate = 49.662(CFS) Time of concentration = 20.000 mm. Effective stream area after confluence = 35.360(Ac.) Process from Point/Station 210.000 to Point/Station 214.000 **** IRREGULAR. CHANNEL FLOW TRAVEL TIME **** Estimated mean flow rate at midpoint of channel = 53.019(CFS) Depth of flow = 1.519(Ft.), Average velocity 7.657(Ft/s) I *** Irregular Channel Data ********* ----------------------------------------------------------------- Information entered for subchannel number 1 I Point number 'X' coordinate 'Y' coordinate 1 0.00 10.00 2 30.00 0.00 3 60.00 10.00 I Manning's 'N' friction factor = 0.035 ----------------------------------------------------------------- Sub-Channel flow = 53.019(CFS) ' flow top width = 9.115(Ft.) I , velocity= 7.657(Ft/s) area = 6.924(Sq.Ft) i t ' Froude number = 1.548 Upstream point elevation = 142.000 (Ft.) Downstream point elevation = 70.000(Ft.) Flow length 1430.000 (Ft.) I Travel time = 3.11 mm. Time of concentration = 23.11 mm. Depth of flow = 1.519 (Ft.) I Average velocity = 7.657(Ft/s) Total irregular channel flow = 53.019(CFS) Irregular channel normal depth above invert elev. = 1.519 (Ft.) Average velocity of channel(s) = 7.657(Ft/s) I Adding area flow to channel Rainfall intensity (I) = 2.552(In/Hr) for a 100.0 year storm Decimal fraction soil group A = 0.000 Decimal fraction Boil group B = 0.000 I Decimal fraction soil group C = 0.000 Decimal fraction soil group D = 1.000 I (UNDISTURBED NATURAL TERRAIN (Permanent Open Space Impervious value, Ai = 0.000 Sub-Area C Value = 0.350 Rainfall intensity = 2.552(In/Hr) for a 100.0 year storm I Effective runoff coefficient used for total area (Q=KCIA) is C = 0.471 CA = 22.060 I I I I Subarea runoff = 6.634(CFS) for 11.500(Ac.) Total runoff = 56.296(CFS) Total area = 46 860(Ac ) Reach E3 Depth of flow = 1.554(Ft.), Average velocity 7.773(Ft/s) Note: Reach E2 = 4686 - 01 = 4676 Acres Process from Point/Station 214.000 to Point/Station 216.000 PIPEFLOW TRAVEL TIME (User specified size) 1r* Upstream point/station elevation = 70.000 (Ft.) Downstream point/station elevation = 60.000(Ft.) Pipe length = 250.00(Ft.) Slope = 0.0400 Manning's N = 0.015 No. of pipes = 1 Required pipe flow = 56.296(CFS) Given pipe size = 30.00(In.) Calculated individual pipe flow = 56.296(CFS) Normal flow depth in pipe 20.16(In.) Flow top width inside pipe = 28.17(In.) Critical Depth = 28.38(In.) Pipe flow velocity = 16.06 (Ft/a) Travel time through pipe = 0.26 mm. Time of concentration (TC) 23.37 mm. Process from Point/Station 214.000 to Point/Station 216.000 **** CONFLUENCE OF MAIN STREAMS The following data inside Main Stream is listed: In Main Stream number: 1 Stream flow area = 46.860(Ac.) Runoff from this stream = 56.296(CFS) Time of concentration = 23.37 mm. Rainfall intensity = 2.534(tn/Hr) Program is now starting with Main Stream No. 2 Process from Point/Station 218.000 to Point/Station 222.000 INITIAL AREA EVALUATION **** Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 0.000 Decimal fraction soil group D = 1.000 [HIGH DENSITY RESIDENTIAL (24.0 DU/A or Less Impervious value, Ai = 0.650 Sub-Area C Value = 0.710 Initial subarea total flow distance = 100.000(Ft.) Highest elevation = 130.500(Ft.) Lowest elevation = 128.700(Ft.) Elevation difference = 1.800(Ft.) Slope = 1.800 Top of Initial Area Slope adjusted by User to 0.740 % Bottom of Initial Area Slope adjusted by User to 0.740 Is. I 8 1 I El I LI El I I El I I I I ri I I I I I I I ri LJ area = 30.066(Sq.Ft) I Froude number = 1.057 Upstream point elevation = 60.000(Ft.) Downstream point elevation = 42.000 (Ft.) Flow length = 600.000(Ft.) Travel time 3.07 mm. Time of concentration = 26.44 mm. Depth of flow = 0.298 (Ft.) Average velocity = 3.260(Ft/s) Total irregular channel flow = 97.999(CFS) Irregular channel normal depth above invert elev. Average velocity of channel(s) = 3.260(Ft/s) 0.298(Ft.) Process from Point/Station 216.000 to Point/Station 2009.000 **** SUBAREA FLOW ADDITION **** Rainfall intensity (I) = 2.340(In/Hr) for a 100.0 year storm Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 0.000 Decimal fraction soil group D = 1.000 [UNDISTURBED NATURAL TERRAIN (Permanent Open Space Impervious value, Ai = 0.000 Sub-Area C Value = 0.350 The area added to the existing stream causes a a lower flow rate of Q = 93.650(CFS) therefore the upstream flow rate of Q = 97.999(CFS) is being used Time of concentration = 26.44 mm. Rainfall intensity = 2.340(In/Hr) for a 100.0 year storm Effective runoff coefficient used for total area (Q=KCIA) is C = 0.492 CA = 40.024 Subarea runoff = 0.000(CFS) for 4.850 (Ac.) Total runoff = 97.999(CFS) Total area = 81 430(Ac ) Reach E4 I ++++++++-f+++++++++++++++++++-3-+++++++++++++++++++++++++++++++++++++++++ I Process from Point/Station 216.000 to Point/Station 2009.000 CONFLUENCE OF MAIN STREAMS **** The following data inside Main Stream is listed: I In Main Stream number: 1 Stream flow area = 81.430 (Ac.) Runoff from this stream = 97.999(CFS) I Time of concentration = 26.44 mm. Rainfall intensity = 2.340(In/Hr) Program is. now starting with Main Stream No. 2 I Process from Point/Station 254.000 to Point/Station 254.000 1 20 I I I I I I I Li Area of streams before confluence: I 114.250 19.180 Results of confluence: Total flow rate = 163.679(CFS) I Time of concentration = 20.880 mm. Effective stream area after confluence = 133.430(Ac.) I Process from Point/Station 272.000 to Point/Station 2009.000 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** I Estimated mean flow rate at midpoint of channel = 163 .727(CFS) Depth of flow = 0.727(Ft.), Average velocity = 4.344(Ft/s) ****** Irregular Channel Data *********** I ----------------------------------------------------------------- Information entered for subchannel number 1 Point number 'X' coordinate 'Y' coordinate 1 0.00 10.00 I 2 30.00 0.00 3 80.00 0.00 4 100.00 10.00 I Manning's 'N' friction factor = 0.035 Sub-Channel flow = 163 .728(CFS) flow top width = 53.637(Ft.) velocity= 4.344(Ft/s) area = 37.692(Sq.Ft) Froude number = 0.913 ' Upstream point elevation = 69.000(Ft.) Downstream point elevation = 42.000 (Ft.) Flow length = 1600.000(Ft.) Travel time = 6.14 mm. I Time of concentration = 27.02 mm. Depth of flow = 0.727 (Ft.) Average velocity = 4.344(Ft/s) Total irregular channel flow = 163.727(CFS) I Irregular channel normal depth above invert elev. = 0.727 (Ft.) Average velocity of channel(s) = 4.344(Ft/s) I Adding area flow to channel Rainfall intensity (I) = 2.307(In/Hr) for a 100.0 year storm Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 0.000 I Decimal fraction soil group D = 1.000 (UNDISTURBED NATURAL TERRAIN ) (Permanent Open Space I Impervious value, Ai = 0.000 Sub-Area C Value = 0.350 The area added to the existing stream causes a a lower flow rate of Q = 151.902(CFS) I therefore the upstream flow rate of Q = 163.679(CFS) is being used Rainfall intensity = 2.307(In/Hr) for a 100.0 year storm 1 36 I I I Effective runoff coefficient used for total area (Q=KCIA) is C 0.429 CA = 65.833 R Subarea runoff = 0000(CFS) for 20.180 (Ac.) Total runoff = 163.679(CFS) Total area :1536j.d(Ac.)';Reach El Depth of flow = 0.727(Ft.), Average velocity = 4.343(Ft/s) Process from Point/Station 272.000 to Point/Station 2009.000 I **** CONFLUENCE OF MAIN STREAMS **** The following data inside Main Stream is listed: I In Main Stream number: 2 Stream flow area = 153.610(Ac.) Runoff from this stream = 163.679(CFS) Time of concentration = 27.02 mm. I Rainfall intensity = 2.307(In/Hr) Summary of stream data: Stream Flow rate TC Rainfall Intensity I No. (CFS) (mm) (In/Hr) I i 97.999 26.44 2.340 2 163.679 27.02 2.307 Qmax(1) = 1.000 * 1.000 * 97.999) + I 1.000 * 0.979 * 163.679) = 258.167 Qmax(2) = 0.986 * 1.000 * 97•999) + 1 1.000 * 1.000 * 163.679) + = 260.317 Total of 2 main streams to confluence: Flow rates before confluence point: I 97.999 163.679 Maximum flow rates at confluence using above data: 258.167 260.317 Area of streams before confluence: I 81.430 153.610 I Results of confluence: Total flow rate = 260.317(CFS) Time of concentration = 27.019 mm. Effective stream area after confluence = 235.040 (Ac.) I Process from Point/Station 2009.000 to Point/Station 2010.000 IRREGULAR CHANNEL FLOW TRAVEL TIME **** I Estimated mean flow rate at midpoint of channel = 260.342(CFS) Depth of flow = 0.680(FtJ, Average velocity = 3.738(Ft/s) Irregular Channel Data ****k 1 37 I Nearest computed pipe diameter 21.00(hn.) Calculated individual pipe flow = 24.726(CFS) Normal flow depth in pipe 13.66 (In.) Flow top width inside pipe = 20.02(In.) Critical depth could not be calculated. Pipe flow velocity = 14.92(Ft/s) Travel time through pipe = 0.78 mm. Time of concentration (TC) = 25.51 mm. Process from Point/Station 2013.000 to Point/Station 2010.000 **** CONFLUENCE OF MINOR STREAMS **** Along Main Stream number: 1 in normal stream number 2 Stream flow area = 12.650(Ac.) Runoff from this stream = 24.726(CFS) Time of concentration = 25.51 mm. Rainfall intensity = 2.394(In/Hr) Summary of stream data: Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr) 1 260.317 29.25 2.192 2 24.726 25.51 2.394 Qmax(l) = 1.000 * 1.000 * 260.317) + 0.916 * 1.000 * 24.726) + = 282.955 Qmax(2) = 1.000 * 0.872 * 260.317) + 1.000 * 1.000 * 24.726) + = 251.779 Total of 2 streams to confluence: Flow rates before confluence point: 260.317 24.726 Maximum flow rates at confluence using above data: 282.955 251.779 Area of streams before confluence: 240.950 12.650 Results of confluence: Total flow rate = 282.955(CFS) Time of concentration = 29.249 mm. Effective stream area after confluence = 253.600(Ac.) Process from Point/Station 2010.000 to Point/Station 2015.000 ** PIPEFLOW TRAVEL TIME (User specified size) *** I Upstream point/station elevation = 35.300 (Ft.) Downstream point/station elevation 34.500 (Ft.) Pipe length = 40.00(Ft.) Slope = 0.0200 Manning's N = 0.013 1 41 I 1 No. of pipes = 1 Required pipe flow = 282 .955(CFS) I Given pipe size = 30.00 (In.) NOTE: Normal flow is pressure flow in user selected pipe size. The approximate hydraulic grade line above the pipe invert is 95.622(Ft.) at the headworks or inlet of the pipe(s) I Pipe friction loss = 19.029(Ft.) Minor friction loss = 77.393(Ft.) K-factor = 1.50 I Critical depth could not be calculated. Pipe flow velocity = 57.64 (Ft/s) Travel time through pipe = 0.01 mm. Time of concentration (TC) = 29.26 mm. End of computations, total study area = 253. 600k (Ac.) Reach E5 Note: Reach E6 253.6 + 0.1 253.7 Acres I I I I 1 I I I I I I 1 42 I I I I I I I I I I I I I I 1 I 1 I I I APPENDIX 4 100 Yr. Proposed Hydrologic Calculations Basin 'E-F' (See Exhibit 'K') I n Process from Point/Station 5000.000 to Point/Station 5000.000 I **** CONFLUENCE OF MAIN STREAMS The following data inside Main Stream is listed: In Main Stream number: 1 Stream flow area = 509.400 (Ac.) I Runoff from this stream = 512.740(CFS) Time of concentration = 31.46 min. I Program Rainfall intensity = 2.092(In/Hr) is now starting with Main Stream No. 2 I Process from Point/Station 5002.000 to Point/Station 5004.000 INITIAL AREA EVALUATION **** I Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 0.000 Decimal fraction soil group D = 1.000 I [UNDISTURBED NATURAL TERRAIN (Permanent Open Space Impervious value, Al = 0.000 ' Sub-Area C Value = 0.350 Initial subarea total flow distance = 100.000(Ft.) Highest elevation = 180.000(Ft.). I Lowest elevation = 130.000(Ft.) Elevation difference = 50.000(Ft.) Slope = 50.000 % Top of Initial Area Slope adjusted by User to 30.000 % INITIAL AREA TIME OF CONCENTRATION CALCULATIONS: The maximum overland flow distance is 100.00 (Ft) I for the top area slope value of 30.00 %, in a development type of Permanent Open Space In Accordance With Figure 3-3 I Initial Area Time of Concentration = 4.34 minutes TC= [1.8*(1.1_C)*distance(Ft.)'.5)/(%slope"(1/3)] TC = t1.8*(1.1_0.3500)*( 100.000".5)/( 30.000(1/3)1= 4.34 Calculated TC of 4.345 minutes is less than 5 minutes, I resetting TC to 5.0 minutes for rainfall intensity calculations Rainfall intensity (I) = 6.850(In/Hr) for a 100.0 year storm Effective runoff coefficient used for area (Q=KCIA) is C = 0.350 Subarea runoff = 0.240(CFS) I Total initial stream area = 0.100(Ac.) I Process from Point/Station 5004.000 to Point/Station 5006.000 IMPROVED CHANNEL TRAVEL TIME I Upstream point elevation = 130.000 (Ft.) Downstream point elevation = 63.000 (Ft.) Channel length thru subarea = 700.000 (Ft.) I Channel base width = 1.000 (Ft.) Slope or 'Z' of left channel bank = 2.000 I 2 I I I Slope or 'Z' of right channel bank = 2.000 Estimated mean flow rate at midpoint of channel = 3.659(CFS) I Manning's 'N' = 0.035 Maximum depth of channel = 2.000(Ft.) Flow(q) thru subarea = 3.659(CFS) I Depth of flow = 0.391(Ft.), Average velocity = 5.259(Ft/s) Channel flow top width = 2.563 (Ft.) Flow Velocity = 5.26(Ft/s) I Travel time = 2.22 mm. Time of concentration = 6.56 mm. Critical depth = 0.531(Ft..) Adding area flow to channel Rainfall intensity (I) = 5.748(In/Hr) for a 100.0 year storm I Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 I Decimal fraction soil group C = 0.000 Decimal fraction soil group ID = 1.000 {UNDISTURBED NATURAL TERRAIN (Permanent Open Space Impervious value, Ai = 0.000 I Sub-Area C Value = 0.350 Rainfall intensity = 5.748(In/Hr) for a 100.0 year storm Effective runoff coefficient used for total area I (Q=KCIA) is C 0.350 CA = 1.214 Subarea runoff = 6.741(CFS) for 3.370(Ac.) Total runoff 6.981(CFS) Total area 3.470(Ac.) Reach W1 Depth of flow = 0.538(Ft.), Average velocity = 6.247(Ft/s) I Critical depth = 0.734(Ft.) ++++++++++++++++-f++++++++++++++++++++++++++++++++++++++++++++++++++++ I Process from Point/Station 5006.000 to Point/Station 5008.000 PIPEFLOW TRAVEL TIME (User specified size) I . Upstream point/station elevation = 63.000(Ft.) Downstream point/station elevation = 61.800 (Ft.) Pipe length = 68.00(Ft.) Slope = 0.0176 Manning's N = 0.013 .No. of pipes = 1 Required pipe flow = 6.981(CFS) I Given pipe size = 18.00(In.) Calculated individual pipe flow = 6.981(CFS) Normal flow depth in pipe = 9.00 (In.) I Flow top width inside pipe = 18.00(In.) Critical Depth = 12.28(In.) Pipe flow velocity = 7.90 (Ft/s) I Travel time through pipe = 0.14 mm. Time of concentration (TC) = 6.71 mm. I Process from Point/Station 5008.000 to Point/Station 5000.000 IMPROVED CHANNEL TRAVEL TIME I Upstream point elevation 61.800(Ft.) Downstream point elevation = 57.000 (Ft.) I . I I I I [1 --I I Channel length thru subarea = 330.000 (Ft..) Channel base width = 1.000(Ft.) Slope or 'Z' of left channel bank = 2.000 Slope or 'Z' of right channel bank = 2.000 Mannings N' = 0.035 Maximum depth of channel = 2.000 (Ft.) Flow(q) thru subarea = 6.981(CFS) Depth of flow = 0.839(Ft.), Average velocity = channel flow top width = 4.356 (Ft.) Flow Velocity = 3.11 (Ft/s) Travel time = 1.77 mm. Time of concentration = 8.48 mm. Critical depth = 0.734(Ft.) 3.107(Ft/s) Process from Point/Station 5008.000 to Point/Station 5000.000 **** CONFLUENCE OF MAIN STREAMS The following data inside Main Stream is listed: In Main Stream number: 2 Stream flow area = 3.470 (Ac.) Runoff from this stream = 6.981(CFS) Time of concentration = 8.48 mm. Rainfall intensity = 4.873(In/Hr) Summary of stream data: Stream Flow rate TC Rainfall Intensity No. (CFS) (mm) (In/Hr) 1 512.740 31.46 2.092 2 6.981 8.48 8.48 4.873 Qxnax(1) 1.000 * 1.000 * 512.740) + 0.429 * 1.000 * 6.981) + = 515.736 Qmax(2) = 1.000 * 0.269 * 512.740) + 1.000 * 1.000 * 6.981) + = 145.135 Total of 2 main streams to confluence: Flow rates before confluence point: 512.740 6.981 Maximum flow rates at confluence using above, data: 515.736 145.135 Area of streams before confluence: 509.400 3.470 Results of confluence: Total flow rate = 515.736(CFS) Time of concentration = 31.460 min. Effective stream area after confluence = 512.870 (.Ac.:.,) Reach W2 (northerly subarea) I I I I I I I 1 I I I I 1 I I Depth of flow = 0.299(Ft.), Average velocity = 1.911(Ft/s) I Streetfiow hydraulics at midpoint of street travel: Halfstreet flow width = 8.129 (Ft.) Flow velocity = 1.91(Ft/s) Travel time = 3.14 min. TC = 9.39 mm. Adding area flow to street I Rainfall intensity (I) = 4.562(In/Hr) for a 100.0 year storm Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 I Decimal fraction soil group C = 0.000 Decimal fraction soil group D = 1.000 [MEDIUM DENSITY RESIDENTIAL (7.3 DU/A or Less I . Impervious value, Ai .= 0.400 Sub-Area C Value = 0.570 Rainfall, intensity = 4.562(In/11r) for a 100.0 year storm I .Effective runoff coefficient used for total area (Q=KCIA) is C = 0.570 CA = 1.180 Subarea runoff = 5.044(CFS) for 1.970(Ac.) Total runoff = 5.382(CFS) Total area = 2.070 (Ac.) I Street flow at end of street = 5.382(CFS) Half street flow at end of street = 2.691(CFS) Depth of flow = 0.348(Ft.), Average velocity = 2.200(Ft/s) Flow width (from curb towards crown)= 10.586(Ft.) ' ++++++++++++++++++.++++..++++++++++++++++++++++++++++++++++++++++++.++ Process from Point/Station 5017.000 to Point/Station 5014.000 PIPEFLOW TRAVEL TIME (User specified size) **** Upstream point/station elevation 135.500 (Ft.) I Downstream point/station elevation = 79.050 (Ft.) Pipe length = 510.00(Ft.) Slope = 0.1107 Maiming's N = 0.013 No. of pipes = 1 Required pipe flow = 5.382(CFS) I Given pipe size = 18.00(In.) Calculated individual pipe flow = 5.382(CFS) Normal flow depth in pipe = 4.78 (In.) I' Flow top width inside pipe = 15.89(m.) Critical Depth = 10.73(In.) Pipe flow velocity = 14.33 (Ft/s) Travel time through pipe = 0.59 mm. Time of concentration (TC) = 9.98 min. I Process from Point/Station 5017.000 to Point/Station 5014.000 CONFLUENCE OF MINOR STREAMS **** Along Main Stream number: 2 in normal stream number 2 I Stream flow area = 2.070(Ac.) Runoff from this stream = 5.382(CFS) Time of concentration 9.98 min. I . Rainfall intensity = 4.385(In/Hr) Summary of stream data: I 9 I... .... ,..,,....... ........... .,.,, ............................., I I I I I I: I Stream Flow rate TC Rainfall Intensity No. (CFS) (mm) (In/Hr) 1 4.498 5.73 6.276 2 5.382 9.98 4.385 Qmax(1) 1.000 * 1.000 * 4.498) + 1.000 * 0.574 * 5.382) + = 7.586 Qmax(2) = 0.699 * 1.000 * 4.498) + 1.000 * 1.000 * 5.382) + = 8.526 Total of 2 streams to confluence: Flow rates before confluence point: 4.498 5.382 Maximum flow rates at confluence using above data: 7.586 8.526 Area of streams before confluence: 2.040 2.070 Results of confluence Total flow rate = 8.526(CFS) Time of concentration = 9.984 mm. Reach W2 Effective stream area after confluence = 4 110(Ac (easterly subarea) Total Area of Reach W2 is northerly + easterly subarea. Process from Point/Station 5014.000 to Paint/Station 5018.000 PIPEFLOW TRAVEL TIME (User specified size) **** Upstream point/station elevation = 79.050 (Ft.) Downstream point/station elevation = 60.000 (Ft.) Pipe length = 96.00(Ft.) Slope = 0.1984 Manning's N 0.013 No. of pipes = 1 Required pipe flow = 8.526(CFS) Given pipe size .= 18.00 (In.) Calculated individual pipe flow = 8.526(CFS) Normal flow depth in pipe 5.20 (In.) Flow top width inside pipe = 16.32 (In.) Critical Depth = 13.57 (In.) Pipe flow velocity = 20.14(Ft/s). Travel time through pipe = 0.08 mm. Time of concentration (TC) = 10.06 min. Process from Point/Station 5018.000 to Point/Station 5010.000 IMPROVED CHANNEL TRAVEL TIME Upstream point elevation = 60.000(Ft.) Downstream point elevation = . 51.000(Ft.) Channel length thru subarea = 460.000 (Ft.) Channel base width = 1.000 (Ft.) Slope or 'Z' of left channel bank = 2.000 I, 10 I I I I I ----------------------------------------------------------------- Sub-Channel flow = 22.805(CFS) flow top width = 7.226 (Ft.) velocity= 3.494(Ft/s) I area = 6.527(Sq.Ft) Froude number = 0.648 Upstream point elevation = 43.620(Ft.) Downstream point elevation = 42.000 (Ft.) Flow length = 180.000(Ft) Travel time = 0.86 mm. Time of concentration = 9.93 nun. Depth of flow = 1.807 (Ft.) Average velocity = 3.494(Ft/s) Total irregular channel flow = 22.805(CFS) Irregular channel normal depth above invert elev. = 1.807 (Ft.) Average velocity of channel(s) = 3.494(Ft/s) Process from Point/Station 5050.000 to Point/Station 5034.000 **** CONFLUENCE OF MAIN STREAMS The following data inside Main Stream is listed; In Main Stream number: 2 Stream flow area = 6.610(Ac.) Runoff from this stream = 22.805(CFS) Time of concentration = 9.93 mm. Rainfall intensity = 4.402(In/Hr) Summary of stream data: Stream Flow rate TC Rainfall Intensity No. (CFS) (mm) (In/Hr) 1 719.611 35.74 1.926 2 22.805 9.93 4.402 Qmax(1) = 1.000 * .1.000 *• 719.611) + 0.438 * 1.000 * 22.805) + = 729.591 Qmax(2) = 1.000 * 0.278 * 719.611) + 1.000 * 1.000 * 22.805) + = 222.633 Total of 2 main streams to confluence: Flow rates before confluence point: 719.611 22.805 Maximum flow rates at confluence using above data: 729.591 222.633 Area of streams before confluence: 707.440 6.610 Results of confluence: 21 I I 1 I I I I I I I I 1 I i Total flow rate = 729.591(CFS) Time of concentration = 35.742 mm. Effective stream area after confluence = 714 050 (Ac ) Reach W3 I Process from Point/Station 5034.000 to Point/Station 5052.000 * * * * IMPROVED CHANNEL TRAVEL TIME * * * * EXISTING DOUBLE 8' X4' RCS I I I Covered channel Upstream point elevation = 42.000(Ft.) Downstream point elevation = 40.000 (Ft.) Channel length thru subarea = 108.000 (Ft.) Channel base width = 16.000 (Ft.) Slope or 'Z' of left channel bank = 0.000 Slope or 'Z' of right channel bank = 0.000 Manning's 'N' = 0.015 Maximum depth of channel = 4.000 (Ft.) Flow(q) thru subarea = 729.591(CFS) Depth of flow = 2.298(Ft.), Average velocity = Channel flow top width = 16.000(Ft.) Flow Velocity = 19.84 (Ftls) Travel time = 0.09 mm. Time of concentration = 35.83 mm. Critical depth = 4.000 (Ft.) OOr 72T9 cfs M 19.840 (Ft/s) Process from Point/Station 5034.000 to Point/Station 5052.000 **** CONFLUENCE OF MAIN STREAMS **** The following data inside Main Stream is listed: In Main Stream number: 1 Stream flow area = 714.050 (Ac.) Runoff from this stream 729.591(CFS) Time of concentration = 35.83 mm. Rainfall intensity = 1.923(In/Hr) Program is now starting with Main Stream No. 2 Process from Point/Station 7000.000 to Point/Station 7007.000 USER DEFINED FLOW INFORMATION AT A POINT User specified 'C value of 0.700 given for subarea Rainfall intensity (I) = 3.229(In/Hr) for a 100.0 year storm User specified values are as follows: TC = 16.05 mm. Rain intensity = 3.23 (in/Hr) Total area = 72.820(Ac.) Total runoff = 163.030(CFS) Process from Point/Station 7000.000 to Point/Station 7007.000 **** CONFLUENCE OF MAIN STREAMS **** I 22 I I E I I 1 729.591 35.83 1.923 2 163.030 16.05 3.229 3 13.200 6.67 5.688 Qmax(l) = 1.000 * 1.000 * 729.591) + 0.596 * 1.000 * 163.030) + 0.338 * 1.000 * 13.200) + = Qinax(2) = 1.000 * 0.448 * 729.591) + 1.000 * 1.000 * 163.030) + 0.568 * 1.000 * 13.200) + = Qmax(3) 1.000 * 0.186 * 729.591) + 1.000 * 0.416 * 163.030) + 1.000 * 1.000 * 13.200) + = Total of 3 main streams to confluence: 23 I I I I I' I 831.169 497.314 216.759 The following data inside Main Stream is listed: In Main Stream number: 2 Stream flow area = 72.820(Ac.) Runoff from this stream = 163.030(CFS) Time of concentration = 16.05 mm. Rainfall intensity = 3.229(In/Hr) Program is now starting with Main Stream No. 3 Process from Point/Station 8003.000 to Point/Station 7007.000 USER DEFINED FLOW INFORMATION AT A POINT **** User specified 'C' value of 0.900 given for subarea Rainfall intensity (I) = 5.688(In/Hr) for a 100.0 year storm User specified values are as follows: TC = 6.67 mm. Rain intensity = 5.69 (In/Hr) Total area = 2.450(Ac.) Total runoff = 13.200(CFS) Process from Point/Station 8003.000 to Point/Station 7007.000 **** CONFLUENCE OF MAIN STREAMS The following data inside Main Stream is listed: In Main Stream number: 3 Stream flow area = 2.450 (Ac.) Runoff from this stream = 13.200(CFS) Time of concentration = 6.67 mm. Rainfall intensity = 5.688(InfHr) Summary of stream data: Stream Flow rate TC Rainfall Intensity No. (CPS) (mm) (In/Hr) I I I I I I I I I I I Flow rates before confluence point: I 729.591 163.030 13.200 Maximum flow rates at confluence using above data: - 831.169 497.314 216.759 Area of streams before confluence: 714.050 72.820 2.450 I Results of confluence: Total flow rate = 831.169(CFS) Time of concentration = 35.833 mm. Effective stream area after confluence 789.320(Ac.) I End of computations total study area = 789.320 (Ac This is the area into the upper end of Reach W4. The total area I tributary to Reach W4 is 78932 acres plus the tributary area downstream of El Camino Real, which was delineated from the topographic mapping on the Study Area Exhibit and is 22.70 acres. I I I I I I I I I I I I 24 I I I I I I I I I I I I I I I I I I I EXCERPTS FROM CHANG CONSULTANTS' "LOMR REQUEST FOR ROBERTSON'S RANCH" SHOWING DRAINAGE AREA TRIBUTARY TO REACH E7 (4.68 ACRES) AND E8 (5.11 ACRES) sMq.By FJJ3 IN CUBIC PEEP PER SPEUBD TIME IN RCUPS, JRFA 114 9?3T.RE MIlES PEAK TIME OF MMAGE EICW FM MMM PERIOD BASIN 4AXlHI4 TIME OF OPEPAT1134 STMCN FW4 PERK ATEA SWE MX STAGE 6-IrAJR 24-HcUR 72-HOUR HYDRAPH AT Cl 505. 10.25 249. 102. 98. .87 BODIED TO CUEEThEL 504. 10.25 249. 102. 98. .87 335.64 10.25 BODIED TO C1-C2 361. 11.00 235. 98. 95. .87 240.99 11.00 FrLDRAPH AT 2 1519. 10.33 760. 311. 299. 272 2 XIiBINED AT cX14BINE 1831. 10.42 988. 409. 394. 3.59 BODIED TO E10AIA 1348. 11.17 745. 291. 280. 3.59 218.76 11.17 PY111D TO 2-4C3 1325. 11.33 743. 290. 279. 3.59 100.24 11.33 }PDPEGU½PH AT C3 475. 10.08 224. 91. 88. .88 2 cfliBINED AT O31BINE 1501. 11.17 879. 381. 367. 4.47 R3JIED TO L11INBJB 971. 12.58 832. 381. 367. 4.47 76.38 12.58 DIVERSICN TO DIVKTH 473. 12.58 421. 181. 174. 4.47 J-FLI3OIR?iPH AT DIVcC 498. 12.58 411. 200. 193. 4.47 I-FLDR,PH AT C4 629. 10.42 314. 128. 123. 1.24 2 0P4BINED AT XMBINE 907. 10.67 681. 328. 316. 5.71 BODIED TO C3&-RCC 896. 10.83 680. 326. 314. 5.71 46.10 10.83 HYDFOAPB AT RCC 26. 10.00 12. 5. 5. .05 2 cXBINED AT rxt1rAL 909. 10.75 691. 331. 319. 5.76 IWDBIGP.PH AT RE1PD1V 473. 12.58 421. 181. 174. .00 BIIYIED TO BINDR 473. 12.75 421. 179. 173. .00 I I I I I I I I I I I I 1 1 I I I I I + IWDAPH AT + PRc2 99. 10.08 46. 19. 18. 2 Q31BINED AT + BOX 497. 12.17 444. 198. 191. HYDAPH AT + RPOH 198. 10.00 92. 38. 36. 2 CDSLIED AT + EX8x8 549. 12.08 504. 236. 227. PWIED TO + NUBSERY 545. 12.50 503. 236. 227. + RcL END OF HM-1 *** 40.37 12.75 Reach E7 to here .21 .43 Reach E8 to here .63 .63 35.34 12.50 DRAINAGE AREA EXHIBIT FROM CHANG CONSULTANTS LOMR • S * . 1 I .. ' - **•. *_'• i / At 4- ad - ... r '-- 8C2 . BC3 •- - + 1BASIN - A113 BJB L C3 AH1 BASIN C4 BC4 RRCH / BJ / AH2 RRC2 +. C RCA DSAH • AH9 A87 - "\- - • *1 AH11L+ FARADAY AH4 SIN AHB MELROSE BASIN AHB - AH5 Legend - -- -- Major Watersheds Drainage Basins Detention Basins I .. •• •---: + I I I APPENDIX B I SCCWRP FIELD SCREENING DATA I I I I I I I U I I I I I I I I Chapter 5 Open Channels I I Table 5-13 Maximum Permissible Velocities for Lined and, Unlined Channels Material or Lining Maximum Permissible Average Velocity* (ft/sec) Natural and Improved Unlined Channels Fine Sand, Colloidal............................ .------- ........ .. ............................ .................................. .................1.50 SandyLoam, Noncollôidal ----------------------------------------------------------------------------------------------------------------115 Silt Loam, Noncolloidal ---- ------------ ------ ----------------- ---------- ------------ - ----------- - -------- -------------------- -.. ----------2.00 AlluvialSdts;Noncolioidal -------------- --------------------- -----------------....... --------------------------------------- --- ...... 2.00 Ordinary Firm Loam ---- ---------- ------- ----------------- ----- ----------------- ---------------------------------- -------- -- -------- ----2.50 VolcanicAsh ---------------------------------------------------------------------------------------------------------------------------------------2:50 StiffClay, Very Colloidal ...................................... -----------------------......... ___ ------- -- ....... ------------------... 3.75 Alluvial Silts, Collodat ----------------------------. ----------------------------------------------------------------------------------------------------------375 ShalesAnd 1-Iardpans -------------------------------------------------------------------------------------------------------------------6.00 FineGravel--- ............. --------..... --- ....... ------------------------................... -- ....... - --------- --------- ... -... -- ....... -------2.50 Graded Loam To Cobbles When Noncolloidal _3.75 Giaded Silts To Cobbles When Colluithil-- ------------ ------------................ ---------____ ---------------------- ----4.00 . Coarse.Gravel, Noncolloidal...---------------- ------ - --- CobblesAnd Shingles---------------------------------------------------------- SandySilt ------------------------............. -............ ---------------------------------- ------- ---------................. ----------------... 2.00 Silty Clay .------------------------------------....... --- ... --------- ........ -........ ------- ...... ----------------------........ -------------------------------------2.50 Clay.......................................................................................................... -----------------------------------6.00 PoorSedimentary Rock ----------------------------------------------------------------- -------- -------- ---------...................... 10.0 Fully-LinedChannels ... - tJnreinforced Vegetation, ...... --------------------------- ------- ---------------------------------------------.. -------------- 0-0 Reinforced Turf ------------------------ ------ ---------------------------------------- -------------- ----------------- ---------------- ---------------------------- i LooseRiprap -- --------------------------- -------------- ------------------- ---- ---- ---------- -------------- -------------- ----per Table 5-2 GroutedRiprap .............................................................................................................................25.0 Gabions...... --....................... -------------------------------------------------------- ----- ------- -------- -..... ---- --------------- ----15.0 SoilCement ----- -------------- -------------------....... ------ ....... --------------------------------------- ---- -- ----------- -................ 15.0 Concrete-----------------------------------------------------------------------------------------------------------------------------------------350 A4a*imum pe/misslb!e velocity fisted here Is basic guideline, higher design velocities maybe use provided appropriate technical documentatfol from manufacturer. I I I San Diego County Drainage Design Manual Page 5-43 July 2005 I I I I I I I I [1 I Form 3 Support Materials Form 3 Checklists I and 2, along with information recording in Form 3 Table 1, are intended to support the decisions pathways illustrated in Form 3 Overall Vertical Rating for Intermediate/Transitional Bed. Form 3 Checklist 1: Armoring Potential El A A mix of coarse gravels and cobbles that are tightly packed with <5% surface material of diameter <2 mm X B Intermediate to A and C or hardpan of unknown resistance, spatial extent (longitudinal and depth), or unknown armoring potential due to surface veneer covering gravel or coarser layer encountered with probe C Gravels/cobbles that are loosely packed or >25% surface material of diameter <2 mm Form 3 Figure 2. Armoring potential photographic supplement for assessing intermediate beds (16 < d5o < 128 mm) to be used in conjunction with Form 3 Checklist I. (Sheet 2 of 4) RESULT FOR ALL STUDY REACHES B-7 Form 3 Checklist 2: Grade Control X A Grade control is present with spacing <50 m or 2/S. m No evidence of failure/ineffectiveness, e.g., no headcutting (>30 cm), no active mass wasting (analyst cannot say grade control sufficient if mass- wasting checklist indicates presence of bank failure), no exposed bridge pilings, no culverts/structures undermined Hard points in serviceable condition at decadal time scale, eg., no apparent undermining, flanking, failing grout If geologic grade control, rock should be resistant igneous and/or metamorphic; For sedimentary/hardpan to be classified as grade control', it should be of demonstrable strength as indicated by field testing such as hammer test/borings and/or inspected by appropriate stakeholder a B Intermediate to A and C - artificial or geologic grade control present but spaced 2/Sv m to 4/Sv m or potential evidence of failure or hardpan of uncertain resistance C Grade control absent, spaced >100 m or >41S\, m, or clear evidence of ineffectiveness Form 3 Figure 3. Grade-control (condition) photographic supplement for assessing intermediate beds (16 <d50 < 128 mm) to be used in conjunction with Form 3 Checklist 2. Sheet 3 of 4) RESULT FOR ALL STUDY REACHES MY .i 128 0.145 96 0.125 in E E 80 0.114 64mm for dense 64 0.101 vegetation in , 48 0.087 Reaches E1-E4, 32 0.070 E8, and W1-W4 16 0.049 8 0031 4 0.026 12 V 2 0.022 1 0.018 05 0015 + Incising 90%risk Al 'I d50 (mm) 10 11 mm Stable x Braided 10%risk 50%risk 0,001 BE Li I Regionally-Calibrated Screening Index Threshold for Incising/Braiding For transitional bed channels (d50 between 16 and 128 mm) or labile beds (channel not incised past critical bank height), use Form 3 Figure 3 to determine Screening Index Score and complete Form 3 Table 1. I I Graphed results apply to Reaches E5, E6, and E7. I I I Form 3 Figure 4. Probability of incising/braiding based on logistic regression of Screening Index and d50 to be used in conjunction with Form 3 Table 1. Form 3 Table 1. Values for Screening Index Threshold (probability of incising/braiding) to be used in conjunction with Form 3 Figure 4 (above) to complete Form 3 Overall Vertical Rating for Intermediate/Transitional Bed (below).. Screening Index Score .-'A = <50% probability of incision: for current Q10, valley slope, and d50; B = Hardpan/d50 indeterminate; and C = >50% probability of incising/braiding for current 010, valley slope, and d50. * 0.5 1.5 0.5 d50 (mm) S*QioOS (m1'51s°'5) 50% risk of incising/braiding Screening Index Score From Form 2 From Form I from fable in Form 3 Figure 3 above , B, C) Overall Vertical Rating for Intermediate/Transitional Bed Calculate the overall Vertical Rating for Transitional Bed channels using the formula below. Numeric values for responses to Form 3 Checklists and Table I as follows: A = 3, B = 6, C = 9. Vertical Rating = J {c.j armoring grade control) screening index score} 6 x 3 x 3= 3.6 Vertical Susceptibility based on Vertical Rating: <4.5 = LOW; 4.5 to 7 = MEDIUM; and >7 = HIGH. (Sheet 4 of 4) RESULT FOR ALL STUDY REACHES B-9 Li I I I 1 Li I I I I I I I 01 - 8 I r S3H3V3 AfliS liv aOI ilflS3I L (L io L jooq) 1 I I j I I LI I I I .9 wioj ui pap/oAd suo!;senb jo a3uanb3s asn No a;is pesodod .ioj AMqed/sepou aeudoidde aiau 1HS 121:I A11I8I1d33SflS yjyi :p INèIOJ I Li I I I I I I I I I I I I I I I I FORM 6: PROBABILITY OF MASS WASTING BANK FAILURE If mass wasting is not currently extensive and the banks are moderately- to well-consolidated, measure bank height and angle at several locations (i.e., at least three locations that capture the range of conditions present in the study reach) to estimate representative values for the reach. Use Form 6 Figure 1 below to determine if risk of bank failure is >10% and complete Form 6 Table 1. Support your results with photographs that include a protractor/rod/tape/person for scale. Bank Angle Bank Height Corresponding Bank Height for Bank Failure Risk (degrees) (m) 10% Risk of Mass Wasting (m) (00% Risk) (from Field) (from Field) (from Form 6 Figure 1 below) (>10% Risk) Left Bank ---- 2m --- <10% Right Bank ---- 2 m <10% .1 30 7.6 O Stable - -- 1096 Risk —50% Risk 90% Risk X Unstable 40 3.7 4. x 45 2.1 0 ' X I • 50 1.5 D •'- . Ii X X .' 1 55 1.1 0 \ 60 0.85 :j cP 0 X . . . 65 0.66 0 00 0 70 0.52 00 0 . X. X 1 :O o') 0 .. x so 0.34 90 0.24 OO 0 . 30 40 50 60 70 Bank Angle. (degrees) Form 6 Figure 1. Probability Mass Wasting diagram, Bank Angle:Heightl% Risk table, and Band Height:Angie schematic. (Sheet I of 1) I RESULT FOR ALL STUDY REACHES B - 12 I -rn Nap Details Result View CRITICAL STRESS CALCULATOR RESULTS FOR REACH El ' Define Drainage Basins Agua HedluHda Jtrsiied Ranch Cotera & El CH;:j R [ocJ Manage Your Point of Compliance (P00) Analyze the receiving water at the 'Point of Compliance' by completing this form Click Edit and enter the appropriate fields, then click the Channel Susceptibility: 110W Update button to calculate the critical flow and low-flow threshold condition Finally. click Save to commit the changes Low Flow Threshold: 10.502 ' '• Channel Assessed: Yes Vertical Susceptibility: Low (Vertical) Watershed Area (ac): 0.24 Lateral Susceptibility: 1Low tateraii Tj Material: lVegetation Roughness: 0100 Channel Top Width (ft): 1100.0 Channel Bottom Width (ft): 120.0 Channel Height (ft): 15.0 Channel Slope: [0.02891 , ' T1 Ma Details Result View CRITICAL STRESS CALCULATOR RESULTS FOR REACH E2 Define Drainage Basins Agua Hedondi Waershid Ranch Costera & El Camino Rua) i dui Manage Your Point of Compliance (POC) Analyze the receiving water at the Point of Compliance by completing this form. Click Edit and enter the appropriate fields then click the Update button to calculate the critical flow and lowflow, threshold condition. Finally, click Save to commit the changes. Channel Susceptibility: ILOW Low Flow Threshold: iO.502 Channel Assessed: IYes Vertical Susceptibility: Low (Vertical) Watershed Area (ac): 10.0731 Lateral Susceptibility: Low (Lateral) V Material: lVegetation Roughness: 0.100 Channel Top Width (ft): 75.0 Channel Bottom Width (ft): 150 Channel Height (ft): 100 Channel Slope: :0,05511 x Mai: Details Result View CRITICAL STRESS CALCULATOR RESULTS FOR REACH E3 Define Drainage Basins Agua Hedionda Watershed Ranch Costera & El Camino Real Widening POC Manage Your Point of Compliance (POC) Analyze the receiving water at the Point of Compliance 'by completing this form Click Edit and enter the appropriate fields then click the Channel Susceptibility: LOW Update button to calculate the critical flow and low-flow threshold - condition Finally click Save to commit the changes Low Flow Threshold: 0.502 Channel Assessed:Yes Vertical Susceptibility: Low (Vertical) Watershed Area (ac): 100732 Lateral Susceptibility: j Low (Lateral) Material: jVegetation Roughness: 0.100 Channel Top Width (ft): 145.0 Channel Bottom Width (ft): 5.0 Channel Height (ft): 110.0 Channel Slope: 0.03691 1 r1ap Details Result View CRITICAL STRESS CALCULATOR RESULTS FOR REACH E4 :1L Define Drainage Basins .U-3 H-Ui iJ itenc'J R.t.:h C..;,tei ) u. POC Manage Your Point of Compliance (POC) Analyze the receiving water at the Point of Compliance by completing . this form. Click Edit and enter the appropriate fields, then click the Channel Susceptibility: LOW Update button to calculate the critical flow and low-flow threshold condition Finally, click Save to commit the changes Low Flow Threshold: 0.502 Channel Assessed: jves Vertical Susceptibility: Low (Vertical) Watershed Area (ac): 0.1272 Lateral Susceptibility: ILow (Lateral) WIN I - 4 'a4 . kttki. - - -. Material: lVegetation Roughness: 0 100 Channel Top Width (ft): 150.0 Channel Bottom Width (ft): i28.0 Channel Height (ft): 5.0 Channel Slope: .0.0247 Map Details Result View CRITICAL STRESS CALCULATOR RESULTS FOR REACH E5 ' Define Drainage Basins Agud HediondaViatershed Ranch Coterd & El Cniino Real Widiti Poc Manage Your Point of Compliance (POC) Analyze the receiving water at the Point of Compliance' by completing this form Click Edit and enter the appropriate fields, then click the Update button to calculate the critical flow and low-flow threshold condition. Finally click Save to commit the changes Channel Susceptibility: LOW Low Flow Threshold: D5Q2 ' Channel Assessed: IYes Vertical Susceptibility: Low (Vertical) '1 Watershed Area (ac): 0.3963 Lateral Susceptibility: jLow (Lateral) Material: Vegetation Roughness: j0.100 Channel Top Width (ft): 150.0 Channel Bottom Width (ft): iXo Channel Height (ft): 5.0 Channel Slope: i óó92I 1111101111111111111 li e Details Result View CRITICAL STRESS CALCULATOR RESULTS FOR REACH E6 ' Define Drainage Basins Aqua HeclUuii late lied Ranch Coski i & El Crw Fl .iJenu1 POC Manage Your Point of Compliance (POC) Analyze the receiving water at the Point of Compliance by completing this form Click Edit and enter the appropriate fields, then click the Update button to calculate the cntical flow and low-flow threshold condition. Finally, click Save to commit the changes Channel Susceptibility: LOW Low Flow Threshold: 6-542 Channel Assessed: Yes Vertical Susceptibility: [Low (Vertical) Watershed Area (ac): 03964 x Lateral Susceptibility: Jil(Lateral) "l Material: [vegetation ' Roughness: 40 100 Channel Top Width (ft): f700 Channel Bottom Width (ft): 15 0 Channel Height (ft): 14.0 Channel Slope: 0.0088 Details Result View CRITICAL STRESS CALCULATOR RESULTS FOR REACH E7 Define Drainage Basins Acjua Hc ondi VVate sMtcl Ranch Costera & El Ca noito Retl Widenina Manage Your Point of Compliance (POC) Analyze the receiving water at the Point of Compliance by completing this form Click Edit and enter the appropriate fields then click the Channel Susceptibility: LOW Update button to calculate the critical flow and low-flow threshold condition Finally. click Save to commit the changes. Low Flow Threshold: 0.502 Channel Assessed: Yes Vertical Susceptibility: Low (Vertical) Watershed Area (ac): 14680 Lateral Susceptibility: jLow (Lateral) Material: lVegetation Roughness: 0.100 Channel Top Width (ft): 1220.0 Channel Bottom Width (ft): 155.0 Channel Height (ft): 14.0 Channel Slope: '13fT0601 x i,lap Details Result View CRITICAL STRESS CALCULATOR RESULTS FOR REACH EB Define Drainage Basins Agua Hedionda Watershed Ranch Costera & El Camino Real Wideni ng _T [Pod 1 Manage Your Point of Compliance (POC) Analyze the receiving water at the Point of Compliance by completing this form Click Edit and erite, the appropriate fields then click the Channel Susceptibility: LOW Update button to calculate the ciitical flaw and low-flow threshold condition Finally, click Save to commit the changes,Low Flow Threshold: 10.502 Channel Assessed: Vertical Susceptibility: ILow (Vertical) Watershed Area (ac): 15.1101 x Lateral Susceptibility: I Low (Lateral) Material: [ation Roughness: 10.10O Channel Top Width (ft): 1500.0 Channel Bottom Width (ft): 185.0 Channel Height (ft): 12.0 Channel Slope: 0.0091 Details Result View CRITICAL STRESS CALCULATOR RESULTS FOR REACH WI Define Drainage Basins PCC Manage Your Point of Compliance (POC) Analyze the receiving water at the Point of Compliance' by completing this form Click Edit and enter the appropriate fields then click the Update button to calculate the critical flow and low-flow threshold condition Finally, click Save to commit the changes. , Agua Hedionda Watershed Channel Susceptibility: LOW Low Flaw Threshold: 0.502 - Ranch Costera & El Camino Real Widening Channel A5sessed: 1Yes Vertical Susceptibility: 1Low icalj T Watershed Area (ac): iO.0054 Lateral Susceptibility: j Low (Lateral) Material: [etation Roughness: 10.100 Channel Top Width (ft): 80.8 Channel Bottom Width (ft): 18.0 Channel Height (ft): 14.0 Channel Slope: 0.0448 Details Result View CRITICAL STRESS CALCULATOR RESULTS FOR REACH W2 ' Define Drainage Basins Acjul ieltJd c:.ti iieu El Cn Manage Your Point of Compliance (POC) Analyze the receiving water at the Point of Compliance by completing this form Click Edit and enter the appropriate fields. then click the Update button to calculate the critical flow and low-flow threshold condition Finally, click Save to commit the changes Channel Assessed: [Yes Watershed Area (ac): Channel Susceptibility: LOW Low Flow Threshold: O,5Q2 Vertical Susceptibility: 1Low '(Vertical) Lateral Susceptibility: (Lateral) Material: [Vegetation Roughness: 0 100 Channel Top Width (ft): 280.0 Channel Bottom Width (ft): 20.0 Channel Height (ft): Channel Slope: 0.0191 c T "X T • ; ; • •;• • Details Result View CRITICAL STRESS CALCULATOR RESULTS FOR REACH W3 Define Drainage Basins Açjua Hedionda Watershed Ranch Costera & El Camillo Real Widening w POC Manage Your Point of Compliance (POC) Analyze the receiving water at the Point of Compliance by completing this form Click Edit and enter the appropriate fields then click the Channel Susceptibility: LOW Update button to calculate the critical flow and low-flow threshold condition Finally click Save to commit the changes Low Flow Threshold: 10.5Q2 Channel Assessed: IYes Vertical Susceptibility: Low (Vertical) v Watershed Area (ac): [:1.1157 Lateral Susceptibility: 11- Lateral Material: Vegetation Roughness: 0100 :- Channel Top Width (ft): 150.0 Channel Bottom Width (ft) 158.0 ----- : Channel Height (ft): 12,0 •ç - - Channel Slope 100127 1at Details Result View CRITICAL STRESS CALCULATOR RESULTS FOR REACH W4 Define Drainage Basins Ayua H dtotuia iiateht.d Rich Custeta & E ii Rei iVItUç POC Manage Your Point of Compliance (POC) Analyze the receiving water at the Point of Compliance by completing this form Click Edit and enter the appropriate fields then click the Update button to calculate the critical flow and low-flow threshold condition Finally click Save to commit the changes Channel Assessed: Yes Watershed Area (ac): 11.2688 Channel Susceptibility: LOW Low Flow Threshold: 10.502 Vertical Susceptibility: j Low (Vertical) Lateral Susceptibility: Low (Lateral) Material: fi7egetation Roughness: 0 100 Channel Top Width (ft): 170.0 Channel Bottom Width (ft): 116.0 Channel Height (ft}: 14.0 Channel Slope: 8.0183 - x RANCHO CCSTER4 _QR4LNQ5JJ/DY PROPOSED CONDITION EXHIBIT A' — mm — mm — — — moo — — — — MM — —