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HomeMy WebLinkAboutParcel Map 17105 Parcel 4 WQMPCity of Temecula WATER QUALITY MANAGEMENT PLAN (WQMP) MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD TEMECULA, CALIFORNIA 92592 APN: 945-070-001 PREPARED BY: VENTURA ENGINEERING INLAND, INC. 27393 YNEZ ROAD, SUITE 159 TEMECULA, CALIFORNIA 92591 (951) 252-7632 wilfredo@venturaengineeringinland.com PREPARED FOR: KEVIN MC GOVERN 40155 PASADENA DRIVE TEMECULA, CALIFORNIA 92591 (951) 837-0633 k-mcgovern@hotmail.com DATE OF WQMP: September 14, 2020 Original: April 8, 2020 APPROVED BY: APPROVAL DATE: WQMP 3 Template Date: October 31st, 2018 Preparation Date: September 14, 2020 Step 1: Source Control BMP Checklist Source Control BMPs All development projects must implement source control BMPs 4.2.1 through 4.2.6 where applicable and feasible. See Chapter 4.2 and Appendix E of the City BMP Design Manual for information to implement source control BMPs shown in this checklist. Answer each category below pursuant to the following: • "Yes" means the project will implement the source control BMP as described in Chapter 4.2 and/or Appendix E of the City BMP Design Manual. Discussion / justification must be provided and show locations on the project plans. Select applicable Source Controls in the Source Control BMP summary on the following page. • "No" means the BMP is applicable to the project but it is not feasible to implement. Discussion / justification must be provided. • "N/A" means the BMP is not applicable at the project site because the project does not include the feature that is addressed by the BMP (e.g., the project has no outdoor materials storage areas). Discussion / justification must be provided. Source Control Requirement Applied? 4.2.1 Prevention of Illicit Discharges into the MS4 ☒ Yes ☐No ☐N/A Discussion / justification: Please see the Source Control BMP Summary for how this will be accomplished. 4.2.2 Storm Drain Stenciling or Signage ☒ Yes ☐No ☐N/A Discussion / justification: Following SC-A, All storm drains 12” or larger will be stenciled. Smaller will not facilitate painted signage. Posts not called for on private property. 4.2.3 Protect Outdoor Materials Storage Areas from Rainfall, Run-On, Runoff, and Wind Dispersal ☐Yes ☐No ☒ N/A Discussion / justification: Not applicable to single-family residences. 4.2.4 Protect Materials Stored in Outdoor Work Areas from Rainfall, Run-On, Runoff, and Wind Dispersal ☐Yes ☐No ☒ N/A Discussion / justification: Not applicable to single-family residences. 4.2.5 Protect Trash Storage Areas from Rainfall, Run-On, Runoff, and Wind Dispersal ☒Yes ☐No ☐ N/A Discussion / justification: Trash bins will be kept in the garage. 4.2.6 Additional BMPs Based on Potential Sources of Runoff Pollutants Not specifically shown in 4.2.2-4.2.5, but SC-D1, SC-D2, SC- N, SC-P will also be utilized ☒Yes ☐No ☐ N/A Discussion / justification. Clearly identify which sources of runoff pollutants are discussed: Please see the next sheet. 4 WQMP Preparation Date: September 14, 2020 Template Date: October 31st, 2018 Source Control BMP Summary Select all source control BMPs identified for your project in sections 4.2.1 through 4.2.6 above in the column on the left below. Then select “yes” if the BMP has been implemented and shown on the project plans, “No” if the BMP has not been implemented, or “N/A” if the BMP is not applicable to your project. ☒ SC-A. On-site storm drain inlets ☒ Yes ☐ No ☐ N/A ☐ SC-B. Interior floor drains and elevator shaft sump pumps ☐ Yes ☐ No ☒ N/A ☐ SC-C. Interior parking garages ☐ Yes ☐ No ☒ N/A ☒ SC-D1. Need for future indoor & structural pest control ☒ Yes ☐ No ☐ N/A ☒ SC-D2. Landscape/outdoor pesticide use ☒ Yes ☐ No ☐ N/A ☐ SC-E. Pools, spas, ponds, fountains, and other water features ☐ Yes ☐ No ☒ N/A ☐ SC-F. Food service ☐ Yes ☐ No ☒ N/A ☒ SC-G. Refuse areas ☒ Yes ☐ No ☐ N/A ☐ SC-H. Industrial processes ☐ Yes ☐ No ☒ N/A ☐ SC-I. Outdoor storage of equipment or materials ☐ Yes ☐ No ☒ N/A ☐ SC-J. Vehicle and equipment cleaning ☐ Yes ☐ No ☒ N/A ☐ SC-K. Vehicle/equipment repair and maintenance ☐ Yes ☐ No ☒ N/A ☐ SC-L. Fuel dispensing areas ☐ Yes ☐ No ☒ N/A ☐ SC-M. Loading docks ☐ Yes ☐ No ☒ N/A ☒ SC-N. Fire sprinkler test water ☒ Yes ☐ No ☐ N/A ☒ SC-O. Miscellaneous drain or wash water ☒ Yes ☐ No ☐ N/A ☒ SC-P. Plazas, sidewalks, and parking lots ☒ Yes ☐ No ☐ N/A ☐ SC-Q. Large trash generating facilities ☐ Yes ☐ No ☒ N/A ☐ SC-R. Animal facilities ☐ Yes ☐ No ☒ N/A ☐ SC-S. Plant nurseries and garden centers ☐ Yes ☐ No ☒ N/A ☐ SC-T. Automotive facilities ☐ Yes ☐ No ☒ N/A Note: Show all source control measures applied above on the plan sheets. WQMP 5 Template Date: October 31st, 2018 Preparation Date: September 14, 2020 Step 2: Site Design BMP Checklist Site Design BMPs All development projects must implement site design BMPs SD-A through SD-H where applicable and feasible. See Chapter 4.3 and Appendix E of the City BMP Design Manual for information to implement site design BMPs shown in this checklist. Answer each category below pursuant to the following: • "Yes" means the project will implement the site design BMP as described in Chapter 4.3 and/or Appendix E of the City BMP Design Manual. Discussion / justification must be provided and show locations on the project plans. • "No" means the BMP is applicable to the project but it is not feasible to implement. Discussion / justification must be provided. • "N/A" means the BMP is not applicable at the project site because the project does not include the feature that is addressed by the BMP (e.g., the project site has no existing natural areas to conserve). Discussion / justification must be provided. Site Design Requirement Applied? 4.3.1 Maintain Natural Drainage Pathways and Hydrologic Features ☒ Yes ☐ No ☐ N/A Discussion / justification: Compliance and confluence points are per the hydrology study. 4.3.2 Conserve Natural Areas, Soils, and Vegetation ☒ Yes ☐ No ☐ N/A Discussion / justification: Areas not in the limits of disturbance will be left natural and a protective fence will placed during construction to prevent construction activities in those areas. 4.3.3 Minimize Impervious Area ☒ Yes ☐ No ☐ N/A Discussion / justification: The driveway has been designed to minimal fire width requirements. 4.3.4 Minimize Soil Compaction ☒ Yes ☐ No ☐ N/A Discussion / justification: Areas not in the limits of disturbance will be left natural. In addition, on-site landscape areas shall be compacted as little as possible to promote infiltration through it. Refer to landscape plans. 4.3.5 Impervious Area Dispersion ☒ Yes ☐ No ☐ N/A Discussion / justification: Adjacent landscaping is designed to be retaining. 4.3.6 Runoff Collection ☐ Yes ☐ No ☒ N/A Discussion / justification: Not feasible for single-family residences. 4.3.7 Landscaping with Native or Drought Tolerant Species ☒ Yes ☐ No ☐ N/A Discussion / justification: Landscaping will meet the requirements and the landscaping plan. Refer to the landscape plans for further information on landscaping species. 4.3.8 Harvesting and Using Precipitation ☐ Yes ☐ No ☒ N/A Discussion / justification: Not feasible for single-family residences 6 WQMP Preparation Date: September 14, 2020 Template Date: October 31st, 2018 Step 3: Construction Stormwater BMP Checklist Minimum Required Standard Construction Stormwater BMPs If you answer “Yes” to any of the questions below, your project is subject to Table 1 on the following page (Minimum Required Standard Construction Stormwater BMPs). As noted in Table 1, please select at least the minimum number of required BMPs 1, or as many as are feasible for your project. If no BMP is selected, an explanation must be given in the box provided. The following questions are intended to aid in determining construction BMP requirements for your project. Note: All selected BMPs below must be included on the BMP plan incorporated into the construction plan sets. 1. Will there be soil disturbing activities that will result in exposed soil areas? (This includes minor grading and trenching.) Reference Table 1 Items A, B, D, and E Note: Soil disturbances NOT considered significant include, but are not limited to, change in use, mechanical/electrical/plumbing activities, signs, temporary trailers, interior remodeling, and minor tenant improvement. ☒ Yes ☐ No 2. Will there be asphalt paving, including patching? Reference Table 1 Items D and F ☒ Yes ☐ No 3. Will there be slurries from mortar mixing, coring, or concrete saw cutting? Reference Table 1 Items D and F ☒ Yes ☐ No 4. Will there be solid wastes from concrete demolition and removal, wall construction, or form work? Reference Table 1 Items D and F ☒ Yes ☐ No 5. Will there be stockpiling (soil, compost, asphalt, concrete, solid waste) for over 24 hours? Reference Table 1 Items D and F ☒ Yes ☐ No 6. Will there be dewatering operations? Reference Table 1 Items C and D ☐ Yes ☒ No 7. Will there be temporary on-site storage of construction materials, including mortar mix, raw landscaping and soil stabilization materials, treated lumber, rebar, and plated metal fencing materials? Reference Table 1 Items E and F ☒ Yes ☐ No 8. Will trash or solid waste product be generated from this project? Reference Table 1 Item F ☒ Yes ☐ No 9. Will construction equipment be stored on site (e.g.: fuels, oils, trucks, etc.?) Reference Table 1 Item F ☐ Yes ☒ No 10. Will Portable Sanitary Services (“Porta-potty”) be used on the site? Reference Table 1 Item F ☒ Yes ☐ No 1 Minimum required BMPs are those necessary to comply with the City of Temecula Erosion and Sediment Control Ordinance (Chapter 18.18 et seq.) and the City of Temecula Engineering and Construction Manual (Chapter 18). WQMP 7 Template Date: October 31st, 2018 Preparation Date: September 14, 2020 Table 1. Construction Stormwater BMP Checklist Minimum Required Best Management Practices (BMPs) CALTRANS SW Handbook2 Detail  BMP Selected Reference sheet No.’s where each selected BMP is shown on the plans. If no BMP is selected, an explanation must be provided. A. Select Erosion Control Method for Disturbed Slopes (choose at least one for the appropriate season) Vegetation Stabilization Planting 3 (Summer) SS-2, SS-4 ☐ PG-4 Hydraulic Stabilization Hydroseeding2 (Summer) SS-4 ☒ Bonded Fiber Matrix or Stabilized Fiber Matrix 4 (Winter) SS-3 ☒ Physical Stabilization Erosion Control Blanket3 (Winter) SS-7 ☐ B. Select erosion control method for disturbed flat areas (slope < 5%) (choose at least one) Will use erosion control measures from Item A on flat areas also SS-3, 4, 7 ☒ PG-4 Sediment Desilting Basin (must treat all site runoff) SC-2 ☐ Mulch, straw, wood chips, soil application SS-6, SS-8 ☐ 2 State of California Department of Transportation (Caltrans). 2003. Storm Water Quality Handbooks, Construction Site Best Management Practices (BMPs) Manual. March. Available online at: http://www.dot.ca.gov/hq/construc/stormwater/manuals.htm. 3 If Vegetation Stabilization (Planting or Hydroseeding) is proposed for erosion control it may be installed between May 1st and August 15th. Slope irrigation is in place and needs to be operable for slopes >3 feet. Vegetation must be watered and established prior to October 1st. The owner must implement a contingency physical BMP by August 15th if vegetation establishment does not occur by that date. If landscaping is proposed, erosion control measures must also be used while landscaping is being established. Established vegetation must have a subsurface mat of intertwined mature roots with a uniform vegetative coverage of 70 percent of the natural vegetative coverage or more on all disturbed areas. 4 All slopes over three feet must have established vegetative cover prior to final permit approval. 8 WQMP Preparation Date: September 14, 2020 Template Date: October 31st, 2018 Table 1. Construction Stormwater BMP Checklist (continued) Minimum Required Best Management Practices (BMPs) CALTRANS SW Handbook Detail  BMP Selected Reference sheet No.’s where each selected BMP is shown on the plans. If no BMP is selected, an explanation must be provided. C. If runoff or dewatering operation is concentrated, velocity must be controlled using an energy dissipater Energy Dissipater Outlet Protection 5 SS-10 ☒ PG-4 D. Select sediment control method for all disturbed areas (choose at least one) Silt Fence SC-1 ☒ PG-4 Fiber Rolls (Straw Wattles) SC-5 ☐ Gravel & Sand Bags SC-6 & 8 ☒ Dewatering Filtration NS-2 ☐ Storm Drain Inlet Protection SC-10 ☒ Engineered Desilting Basin (sized for 10-year flow) SC-2 ☐ E. Select method for preventing offsite tracking of sediment (choose at least one) Stabilized Construction Entrance TC-1 ☒ PG-4 Construction Road Stabilization TC-2 ☐ Entrance/Exit Tire Wash TC-3 ☐ Entrance/Exit Inspection & Cleaning Facility TC-1 ☐ Street Sweeping and Vacuuming SC-7 ☒ F. Select the general site management BMPs F.1 Materials Management Material Delivery & Storage WM-1 ☒ PG-4 Spill Prevention and Control WM-4 ☒ F.2 Waste Management 6 Waste Management Concrete Waste Management WM-8 ☒ PG-4 Solid Waste Management WM-5 ☒ Sanitary Waste Management WM-9 ☒ Hazardous Waste Management WM-6 ☐ Note: The Construction General Permit (Order No. 2009-0009-DWQ) also requires all projects not subject to the BMP Design Manual to comply with runoff reduction requirements through the implementation of post-construction BMPs as described in Section XIII of the order. 5 Regional Standard Drawing D-40 – Rip Rap Energy Dissipater is also acceptable for velocity reduction. 6 Not all projects will have every waste identified. The applicant is responsible for identifying wastes that will be onsite and applying the appropriate BMP. For example, if concrete will be used, BMP WM-8 must be selected. WQMP 9 Template Date: October 31st, 2018 Preparation Date: September 14, 2020 Step 4: Project type determination (Standard or Priority Development Project) Is the project part of another Priority Development Project (PDP)? ☒ Yes ☐ No If so, Standard and PDP requirements apply. Go to Step 4.1 and select “PDP” The project is (select one): ☒ New Development ☐ Redevelopment 7 The total proposed newly created or replaced impervious area is: 14,880 ft2 The total existing (pre-project) impervious area is: 0 ft2 The total area disturbed by the project is: 78,401 ft2 If the total area disturbed by the project is 1 acre (43,560 sq. ft.) or more OR the project is part of a larger common plan of development disturbing 1 acre or more, a Waste Discharger Identification (WDID) number must be obtained from the State Water Resources Control Board. WDID: 9 33C390653 Is the project in any of the following categories, (a) through (f)?8 Yes ☒ No ☐ (a) New development projects that create 10,000 square feet or more of impervious surfaces 9(collectively over the entire project site). This includes commercial, industrial, residential, mixed-use, and public development projects on public or private land. Yes ☐ No ☒ (b) Redevelopment projects that create and/or replace 5,000 square feet or more of impervious surface (collectively over the entire project site on an existing site of 10,000 square feet or more of impervious surfaces). This includes commercial, industrial, residential, mixed-use, and public development projects on public or private land. Yes ☐ No ☒ (c) New and redevelopment projects that create and/or replace 5,000 square feet or more of impervious surface (collectively over the entire project site), and support one or more of the following uses: (i) Restaurants. This category is defined as a facility that sells prepared foods and drinks for consumption, including stationary lunch counters and refreshment stands selling prepared foods and drinks for immediate consumption (Standard Industrial Classification (SIC) code 5812). (ii) Hillside development projects. This category includes development on any natural slope that is twenty-five percent or greater. (iii) Parking lots. This category is defined as a land area or facility for the temporary parking or storage of motor vehicles used personally, for business, or for commerce. (iv) Streets, roads, highways, freeways, and driveways. This category is defined as any paved impervious surface used for the transportation of automobiles, trucks, motorcycles, and other vehicles. 7 Redevelopment is defined as: The creation and/or replacement of impervious surface on an already developed site. Examples include the expansion of a building footprint, road widening, the addition to or replacement of a structure, and creation or addition of impervious surfaces. Replacement of impervious surfaces includes any activity that is not part of a routine maintenance activity where impervious material(s) are removed, exposing underlying soil during construction. Redevelopment does not include routine maintenance activities, such as trenching and resurfacing associated with utility work; pavement grinding; resurfacing existing roadways; new sidewalks construction; pedestrian ramps; or bike lanes on existing roads; and routine replacement of damaged pavement, such as pothole repair. 8 Applicants should note that any development project that will create and/or replace 10,000 square feet or more of impervious surface (collectively over the entire project site) is considered a new development. 10 WQMP Preparation Date: September 14, 2020 Template Date: October 31st, 2018 Project type determination (continued) Yes ☐ No ☒ (d) New or redevelopment projects that create and/or replace 2,500 square feet or more of impervious surface (collectively over the entire project site), and discharging directly to an Environmentally Sensitive Area (ESA). “Discharging directly to” includes flow that is conveyed overland a distance of 200 feet or less from the project to the ESA, or conveyed in a pipe or open channel any distance as an isolated flow from the project to the ESA (i.e. not commingled with flows from adjacent lands). Note: ESAs are areas that include but are not limited to all Clean Water Act Section 303(d) impaired water bodies; areas designated as Areas of Special Biological Significance by the State Water Board and San Diego Water Board; State Water Quality Protected Areas; water bodies designated with the RARE beneficial use by the State Water Board and San Diego Water Board; and any other equivalent environmentally sensitive areas which have been identified by the Copermittees. See BMP Design Manual Chapter 1.4.2 for additional guidance. Yes ☐ No ☒ (e) New development projects, or redevelopment projects that create and/or replace 5,000 square feet or more of impervious surface, that support one or more of the following uses: (i) Automotive repair shops. This category is defined as a facility that is categorized in any one of the following SIC codes: 5013, 5014, 5541, 7532-7534, or 7536- 7539. (ii) Retail gasoline outlets (RGOs). This category includes RGOs that meet the following criteria: (a) 5,000 square feet or more or (b) a projected Average Daily Traffic (ADT) of 100 or more vehicles per day. Yes ☒ No ☐ (f) New or redevelopment projects that result in the disturbance of one or more acres of land and are expected to generate pollutants post construction. Note: See BMP Design Manual Chapter 1.4.2 for additional guidance. Does the project meet the definition of one or more of the Priority Development Project categories (a) through (f) listed above? ☐ No – the project is not a Priority Development Project (Standard Project). ☒ Yes – the project is a Priority Development Project (PDP). Further guidance may be found in Chapter 1 and Table 1-2 of the BMP Design Manual. The following is for redevelopment PDPs only: The area of existing (pre-project) impervious area at the project site is: _______________ ft2 (A) The total proposed newly created or replaced impervious area is _______________ ft2 (B) Percent impervious surface created or replaced (B/A)*100: _______________ % The percent impervious surface created or replaced is (select one based on the above calculation): ☐ less than or equal to fifty percent (50%) – only newly created or replaced impervious areas are considered a PDP and subject to stormwater requirements OR ☐ greater than fifty percent (50%) – the entire project site is considered a PDP and subject to stormwater requirements WQMP 11 Template Date: October 31st, 2018 Preparation Date: September 14, 2020 Step 4.1: Water Quality Management Plan requirements Step Answer Progression Is the project a Standard Project, Priority Development Project (PDP), or exception to PDP definitions? To answer this item, complete Step 4 Project Type Determination Checklist, and see PDP exemption information below. For further guidance, see Chapter 1.4 of the BMP Design Manual in its entirety. ☐ Standard Project Standard Project requirements apply, STOP, you have satisfied stormwater requirements. ☒ PDP Standard and PDP requirements apply. Complete Exhibit A “PDP Requirements.” http://temeculaca.gov/wqmpa2 ☐ PDP Exemption Go to Step 4.2 below. Step 4.2: Exemption to PDP definitions Is the project exempt from PDP definitions based on either of the following: ☐ Projects that are only new or retrofit paved sidewalks, bicycle lanes, or trails that meet the following criteria: (i) Designed and constructed to direct stormwater runoff to adjacent vegetated areas, or other non-erodible permeable areas; OR (ii) Designed and constructed to be hydraulically disconnected from paved streets or roads [i.e., runoff from the new improvement does not drain directly onto paved streets or roads]; OR (iii) Designed and constructed with permeable pavements or surfaces in accordance with City of Temecula Guidance on Green Infrastructure; If so: Standard Project requirements apply, AND any additional requirements specific to the type of project. City concurrence with the exemption is required. Provide discussion and list any additional requirements below in this form. STOP, you have satisfied stormwater requirements. ☐ Projects that are only retrofitting or redeveloping existing paved alleys, streets or roads that are designed and constructed in accordance with the City of Temecula Guidance on Green Infrastructure. Complete Exhibit A “PDP Requirements.” Select Green Streets Exemptions where applicable. Discussion / justification, and additional requirements for exceptions to PDP definitions, if applicable: Project is not exempt from PDP requirements. Exhibit A City of Temecula PRIORITY DEVELOPMENT PROJECT REQUIREMENTS ii PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS Preparation Date: September 14, 2020 Template Date: September 26, 2019 This page was left intentionally blank. PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS iii Template Date: September 26, 2019 Preparation Date: September 14, 2020 Table of Contents Table of Contents ......................................................................................................................... iii Attachments ................................................................................................................................. iii Preparer's Certification Page ........................................................................................................ v Step 1: Site Information Checklist ........................................................................................... 7 Step 1.1: Description of Existing Site Condition and Drainage Patterns ............................. 7 Step 1.2: Description of Proposed Site Development and Drainage Patterns .................. 10 Step 1.3: Other Site Requirements and Constraints ......................................................... 12 Step 2: Strategy for Meeting PDP Performance Requirements ............................................ 14 Attachments Attachment 1: Stormwater Pollutant Control BMP Selection Attachment 1a: DMA Exhibit Attachment 1b: 85th percentile 24-hour Isohyetal Map Attachment 1c: Worksheet B.1-1 DCV Attachment 1d: Structural Pollutant Control BMP Checklist(s) Attachment 1e: Attachment 1f: Attachment 2: Hydromodification Control Measures Attachment 2a: Applicability of HMP Requirements Attachment 2b: HMP Exhibit(s) Attachment 2c: Management of Critical Coarse Sediment Yield Areas Attachment 2d: Flow Control Facility Design Attachment 2e: Geomorphic Assessment of Receiving Channels (optional) Attachment 2f: Vector Control Plan (if applicable) Attachment 3: Structural BMP Maintenance Plan Attachment 3a: Structural BMP Maintenance Thresholds and Actions Attachment 3b: Maintenance Agreements / Notifications (when applicable) Attachment 3c: Individual Structural BMP DMA Map book Attachment 4: City of Temecula PDP Structural BMP Verification for DPW Permitted Land Development Projects Attachment 5: Copy of Plan Sheets Showing Permanent Stormwater BMPs Attachment 6: Copy of Project's Drainage Report Attachment 7: Copy of Project's Geotechnical and Groundwater Investigation Report iv PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS Preparation Date: September 14, 2020 Template Date: September 26, 2019 This page was left intentionally blank. vi PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS Preparation Date: September 14, 2020 Template Date: September 26, 2019 This page was left intentionally blank. PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS 7 Template Date: September 26, 2019 Preparation Date: September 14, 2020 Step 1: Site Information Checklist Step 1.1: Description of Existing Site Condition and Drainage Patterns Project Watershed (Complete Hydrologic Unit, Area, and Subarea Name with Numeric Identifier; e.g., 902.52 Santa Margarita HU, Pechanga HA, Wolf HSA) 902.32 Long Canyon, Santa Margarita HU, Murrieta HA, Murrieta HSA Current Status of the Site (select all that apply): ☐ Existing development ☐ Previously graded but not built out ☐ Demolition completed without new construction ☐ Agricultural or other non-impervious use ☒ Vacant, undeveloped/natural Description / Additional Information: Project site is currently vacant land. Existing Land Cover Includes (select all that apply and provide each area on site): ☒ Pervious Area 1.800 Acres ( 78,401 Square Feet) ☐ Impervious Areas _______ Acres (_______Square Feet) Description / Additional Information: Project site is currently vacant land. 8 PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS Preparation Date: September 14, 2020 Template Date: September 26, 2019 How is stormwater runoff conveyed from the site? At a minimum, this description should answer: (1) Whether existing drainage conveyance is natural or urban; (2) Is runoff from offsite conveyed through the site? If yes, describe the offsite drainage areas, design flows, and locations where offsite flows enter the project site, and summarize how such flows are conveyed through the site; (3) Provide details regarding existing project site drainage conveyance network, including any existing storm drains, concrete channels, swales, detention facilities, stormwater treatment facilities, natural or constructed channels; and (4) Identify all discharge locations from the existing project site along with a summary of conveyance system size and capacity for each of the discharge locations. Provide summary of the pre-project drainage areas and design flows to each of the existing runoff discharge locations. Reference the Drainage report Attachment for detailed calculations. Describe existing site drainage patterns: Hydrology Note: Please refer to the hydrology report provided for refence Attachment 6 for full details. (1) The project site currently sheet flows overland to compliance/confluence points A, B, and C along the property lines. In addition, points B and C confluence approximately offsite about 30 feet beyond the property line. (2) Off-site flows are conveyed through the project site via a proposed storm drain under the proposed driveway to maintain natural drainage patterns. In addition, a new swale is being proposed at the base of the main slope to promote the safe conveyance of flows and to prevent localized erosion. (3) There are no non-natural drainage facilities or features on the project site currently. (4) The following is summary of the existing conditions calculations from the hydrology report: EXISTING CONDITIONS RUNOFF COEFFICIENTS DRAINAGE SUB-AREA QUALITY OF COVER SOIL GROUP C GENERAL (ADJUSTED TO AMCII) ALL POOR, UNMAINTAINED UNDISTURBED NATURAL PROPOSED CONDITIONS RUNOFF COEFFICIENTS DRAINAGE SUB-AREA QUALITY OF COVER SOIL GROUP C GENERAL (ADJUSTED TO AMCII) 1.1 – 1.3; 1.6; 1.8 1.10 – 1.11 2.1 – 2.2 3.2 POOR, UNMAINTAINED UNDISTURBED NATURAL 1.4 – 1.5; 1.7; 1.9 3.1 URBAN – SINGLE FAMILY RESIDENTIAL SINGLE-FAMILY RESIDENTIAL 1 DU / ACRE PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS 9 Template Date: September 26, 2019 Preparation Date: September 14, 2020 CONFLUENCE POINT A EXISTING CONDITIONS SUMMARY DATA 100-YEAR TIME OF CONCENTRATION (MIN) 6.49 INTENSITY (IN/HR) 4.861 AREA (ACRES) 4.549 TOTAL DISCHARGE (CFS) 17.5 VELOCITY (FPS) 6.1 CONFLUENCE POINT B EXISTING CONDITIONS SUMMARY DATA 100-YEAR TIME OF CONCENTRATION (MIN) 5.37 INTENSITY (IN/HR) 4.901 AREA (ACRES) 0.507 TOTAL DISCHARGE (CFS) 2.2 VELOCITY (FPS) 7.4 CONFLUENCE POINT C EXISTING CONDITIONS SUMMARY DATA 100-YEAR TIME OF CONCENTRATION (MIN) 5.37 INTENSITY (IN/HR) 4.902 AREA (ACRES) 0.318 TOTAL DISCHARGE (CFS) 1.4 VELOCITY (FPS) 7.4 10 PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS Preparation Date: September 14, 2020 Template Date: September 26, 2019 Step 1.2: Description of Proposed Site Development and Drainage Patterns Project Description / Proposed Land Use and/or Activities: The project proposes the construction of a new single-family residence and associated landscaping, storm drains, paving, BMPs and planting. Proposed Land Cover Includes (select all that apply and provide each area on site): Existing to Remain ☐ Pervious Area _______ Acres (_______ Square Feet) -- N/A, rest of site ☐ Impervious Areas _______ Acres (_______ Square Feet) --- N/A Existing to Be Replaced ☒ Pervious Area: 1.458 Acres (63,522 Square Feet) ☐ Impervious Areas _______ Acres (_______ Square Feet) Newly Created ☒ Pervious Area 1.458 Acres (63,522 Square Feet) ☒ Impervious Areas 0.342 Acres (14,880 Square Feet) Total ☒ Pervious Area: 1.458 Acres (63,522 Square Feet) ☒ Impervious Areas: 0.347 Acres (14,880 Square Feet) Description / Additional Information: List/describe proposed impervious features of the project (e.g., buildings, roadways, parking lots, courtyards, athletic courts, other impervious features): Single-family residence, driveway, patio List/describe proposed pervious features of the project (e.g., landscape areas): Landscaping, revegetated slopes Describe any grading or changes to site topography: Only grading in support of the proposed single-family residence is proposed PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS 11 Template Date: September 26, 2019 Preparation Date: September 14, 2020 Provide details regarding the proposed project site drainage conveyance network, including storm drains, concrete channels, swales, detention facilities, stormwater treatment facilities, natural or constructed channels, and the method for conveying offsite flows through or around the proposed project site. Identify all discharge locations from the proposed project site along with a summary of the conveyance system size and capacity for each of the discharge locations. Provide a summary of pre- and post-project drainage areas and design flows to each of the runoff discharge locations. Reference the drainage study for detailed calculations. Describe proposed site drainage patterns: The project site maintains the same compliance points in the proposed conditions as the existing conditions per the Hydrology and Hydraulics Report provided for reference in Attachment 6. CONFLUENCE POINT A PROPOSED CONDITIONS SUMMARY DATA 100-YEAR TIME OF CONCENTRATION (MIN) 7.45 INTENSITY (IN/HR) 4.095 AREA (ACRES) 4.846 TOTAL DISCHARGE (CFS) 17.1 VELOCITY (FPS) 4.8 CONFLUENCE POINT B PROPOSED CONDITIONS SUMMARY DATA 100-YEAR TIME OF CONCENTRATION (MIN) 5.14 INTENSITY (IN/HR) 5.021 AREA (ACRES) 0.288 TOTAL DISCHARGE (CFS) 1.3 VELOCITY (FPS) 6.2 CONFLUENCE POINT C PROPOSED CONDITIONS SUMMARY DATA 100-YEAR TIME OF CONCENTRATION (MIN) 9.44 INTENSITY (IN/HR) 3.595 AREA (ACRES) 0.497 TOTAL DISCHARGE (CFS) 1.6 VELOCITY (FPS) 8.1 COMPLIANCE POINT A COMPARISON DATA EXISTING CONDITIONS 100-YEAR PROPOSED CONDITION 100-YEAR COMPARISON TIME OF CONCENTRATION (MIN) 6.49 7.45 + 0.96 INTENSITY (IN/HR) 4.861 4.095 - 0.766 AREA (ACRES) 4.549 4.846 + 0.297 TOTAL DISCHARGE (CFS) 17.5 17.1 - 0.4 VELOCITY (FPS) 6.1 4.8 - 1.3 12 PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS Preparation Date: September 14, 2020 Template Date: September 26, 2019 COMPLIANCE POINT B COMPARISON DATA EXISTING CONDITIONS 100-YEAR PROPOSED CONDITION 100-YEAR COMPARISON TIME OF CONCENTRATION (MIN) 5.37 5.14 - 0.23 INTENSITY (IN/HR) 4.901 5.021 + 0.120 AREA (ACRES) 0.507 0.288 - 0.219 TOTAL DISCHARGE (CFS) 2.2 1.3 - 0.9 VELOCITY (FPS) 7.4 6.2 - 1.2 COMPLIANCE POINT C COMPARISON DATA EXISTING CONDITIONS 100-YEAR PROPOSED CONDITION 100-YEAR COMPARISON TIME OF CONCENTRATION (MIN) 5.37 9.44 + 4.07 INTENSITY (IN/HR) 4.902 3.595 + 1.307 AREA (ACRES) 0.318 0.497 + 0.179 TOTAL DISCHARGE (CFS) 1.4 1.6 + 0.2 VELOCITY (FPS) 7.4 8.1 + 0.7 Comparison Point B and C Note: It should be noted that although there is an increase at Comparison Point C of 0.2 cfs in the 100-Tear Design Storm Event, there is also a decrease at Comparison Point B of 0.9 cfs. These two Comparison Points are taken at the physical property line; however, they will confluence approximately 30 feet downstream of each other in another gully so the overall net decrease will be 0.7 cfs in the 100-Year Design Storm Event to the downstream property owner as there are no improvements between the property line at this downstream confluence. Step 1.3: Other Site Requirements and Constraints When applicable, list other site requirements or constraints that will influence stormwater management design, such as zoning requirements including setbacks and open space, or local codes governing minimum street width, sidewalk construction, allowable pavement types, and drainage requirements. No impacts to stormwater design are anticipated at this time. Self-Mitigating and Self-Retaining Areas are being proposed and no structural treatment control BMPs will be required by the project design. PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS 13 Template Date: September 26, 2019 Preparation Date: September 14, 2020 Optional Additional Information or Continuation of Previous Sections As Needed This space provided for additional information or continuation of information from previous sections as needed. N/A 14 PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS Preparation Date: September 14, 2020 Template Date: September 26, 2019 Step 2: Strategy for Meeting PDP Performance Requirements PDPs must implement BMPs to control pollutants in stormwater that may be discharged from a project (see Chapter 5). PDPs subject to hydromodification management requirements must implement flow control BMPs to manage hydromodification (see Chapter 6). Both stormwater pollutant control and flow control can be achieved within the same BMP(s). Projects triggering the 50% rule must address stormwater requirements for the entire site. Structural BMPs must be verified by the City at the completion of construction. This may include requiring the project owner or project owner's representative and engineer of record to certify construction of the structural BMPs (see Chapter 1.12). Structural BMPs must be maintained into perpetuity, and the City must confirm the maintenance (see Chapter 7). Provide a narrative description of the general strategy for pollutant control and flow control at the project site in the box below. This information must describe how the steps for selecting and designing stormwater pollutant control BMPs presented in Chapter 5.1 of the BMP Design Manual were followed, and the results (type of BMPs selected). For projects requiring flow control BMPs, indicate whether pollutant control and flow control BMPs are integrated or separate. At the end of this discussion, provide a summary of all the BMPs within the project including the type and number. Describe the general strategy for BMP implementation at the site. The project site will utilize re-vegetated landscaping to plant proposed slopes. All other DMA sub-areas will drain to the main landscaping areas through dispersion areas and into tree wells for additional controls. Tree well areas will facilitate retention and act as a Self-Retaining areas before being safely discharged through rip rap dissipators to the same general locations as the existing conditions. Through the use of tree wells and Self-Retaining areas, the DCV of each DMA has been reduced to o and therefore the MS4 permit requirements of retention are met prior to the implementation of other BMPs. In addition, the tree wells have been sized to mitigate HMP by treating 2.5 time (the soil factor) of the DVC. (Continue on following page as necessary.) PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS 15 Template Date: September 26, 2019 Preparation Date: September 14, 2020 Description of structural BMP strategy continued (Page reserved for continuation of description of general strategy for structural BMP implementation at the site) (Continued from previous page) N/A 16 PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS Preparation Date: September 14, 2020 Template Date: September 26, 2019 ATTACHMENT 1 STORMWATER POLLUTANT CONTROL BMP SELECTION Indicate which Items are Included behind this cover sheet: Attachment Sequence Contents Checklist Special Considerations for Redevelopment Projects (50% Rule) see chapter 1.7 and Step 4 of Appendix A.1. ☐ Less than or equal to fifty percent (50%) ☐ Greater than fifty percent (50%) Refer to Figure 5-1: Stormwater Pollutant Control BMP Selection Flow Chart Attachment 1a DMA Exhibit (Required) See DMA Exhibit Checklist on the back of this form. See Chapter 3.3.3 for guidance ☒ Included ☐ Entire project is designed with Self-Mitigating and De-Minimis DMAs. The project is compliant with Pollution Control BMP sizing requirements. STOP * Attachment 1b Figure B.1-1: 85th Percentile 24-hour Isohyetal Map with project location ☒ Included Attachment 1c Worksheet B.2-1 DCV 1 ☒ Included Attachment 1d Applicable Site Design BMP Fact Sheet(s) from Appendix E ☒ Included ☒ Entire project is designed with Self-Retaining DMAs. The project is compliant with Pollution Control BMP sizing requirements. STOP * Attachment 1e Structural Pollutant Control BMP Checklist(s) ☐ Included Attachment 1f Is Onsite Alternative Compliance proposed?2 ☐ No ☐ Yes - Include WQE worksheets Attachment 1g Offsite Alternative Compliance Participation Form - Pollutant Control Refer to Figure 1-3:Pathways to Participating in Offsite Alternative Compliance Program ☐ Full Compliance Onsite ☐ Partial Compliance Onsite with Offsite Alternative Compliance or Full Offsite Alternative Compliance. Document onsite structural BMPs and complete - Pollutant Control Offsite Alternative Compliance Participation Form, and - WQE worksheets * If this box is checked, the remainder of Attachment 1 does not need to be filled out. 1 All stormwater pollutant control worksheets have been automated and are available for download at: https://www.sandiegocounty.gov/content/sdc/dpw/watersheds/DevelopmentandConstruction/BMP_Design_Manual. html 2 Water Quality Equivalency Guidance and automated worksheets for Region 9: http://www.projectcleanwater.org/water-quality-equivalency-guidance/ PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS 17 Template Date: September 26, 2019 Preparation Date: September 14, 2020 Atachmnet 1a: DMA Exhibit Checklist See Chapter 3.3.3 for guidance ☒ Point(s) of Compliance ☒ Project Site Boundary ☒ Project Disturbed Area Footprint ☒ Drainage management area (DMA) boundaries, DMA ID numbers, DMA areas (square footage or acreage), and DMA type (i.e., drains to structural BMP, self-retaining, self- mitigating, or de-minimis) Note on exhibit de-minimis areas and discuss reason they could not be included in Step 1.3 per section 5.2.2 of the manual. Include offsite areas receiving treatment to mitigate Onsite Water Quality Equivalency. ☒ Include summary table of worksheet inputs for each DMA. ☒ Include description of self-mitigating areas. ☒ Potential pollutant source areas and corresponding required source control BMPs (see Chapter 4, Appendix E.1, and Step 3.5) ☒ Proposed Site Design BMPs and surface treatments used to minimize imperviousness. Show sections, details, and dimensions of site design BMP’s per chapter 5.2.3 (tree wells, dispersion areas, rain gardens, permeable pavement, rain barrels, green roofs, etc.) ☐ Proposed Harvest and Use BMPs ☒ Underlying hydrologic soil group (Web Soil Survey) ☒ Existing natural hydrologic features (watercourses, seeps, springs, wetlands, pond, lake) ☒ Existing topography and impervious areas ☒ Proposed grading and impervious areas. If the project is a subdivision or spans multiple lots show pervious and impervious totals for each lot. ☒ Existing and proposed site drainage network and connections to drainage offsite ☒ Potable water wells, onsite wastewater treatment systems (septic), underground utilities ☐ Structural BMPs (identify location, structural BMP ID No., type of BMP, and size/detail) ☐ Approximate depth to groundwater at each structural BMP ☐ Approximate infiltration rate and feasibility (full retention, partial retention, biofiltration) at each structural BMP ☐ Critical coarse sediment yield areas to be protected and or conveyed through the project site, if applicable. ☐ Temporary Construction BMPs. Include protection of source control, site design and structural BMPs during construction. 18 PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS Preparation Date: September 14, 2020 Template Date: September 26, 2019 Attachment 1e: Structural Pollutant Control BMP Checklist Provide the following items for each Structural BMP selected Refer to Figure 5-2: Stormwater Pollutant Control Structural BMP Selection Flow Chart DMA ID No. Structural BMP ID No. Construction Plan Sheet No. ☐ Worksheet B.3-1 Structural BMP Feasibility: Project-Scale BMP Feasibility Analysis ☐ Worksheet C.4-1: Categorization of Infiltration Feasibility Condition Refer to Appendices C and D to complete. ☐ Not included because the entire project will use harvest and use BMPs ☐ Worksheet D.5-1 Infiltration & partial retention Safety Factor Structural BMP Selection and Design (Chapter 5.5) complete an include the applicable worksheet(s) found in appendix B and design criteria checklists from the associated fact sheets found in appendix E for selected Structural BMP(s): ☐ Worksheet B.6-1 - Flow-thru treatment control included as pre-treatment/forebay for an onsite retention or biofiltration BMP (provide BMP type/description and indicate which onsite retention or biofiltration BMP it serves in discussion section below) ☐ Retention by harvest and use (HU-1) ☐ Continuous simulation Model ☐ Worksheet B.4-1 ☐ Infiltration basin (INF-1) ☐ Bioretention (INF-2) ☐ Permeable pavement (INF-3) ☐ Worksheet B.5-1 ☐ Biofiltration with partial retention (PR-1) ☐ Biofiltration (BF-1) ☐ Biofiltration with Nutrient Sensitive Media Design (BF-2) ☐ Identification and Narrative of Receiving Water Pollutants of Concern ☐ Proprietary Biofiltration (BF-3) ☐ Appendix F checklist ☐ Identification and Narrative of Receiving Water Pollutants of Concern ☐ Worksheet B.5-3 Minimum Footprint ☐ Worksheet B.5-4 Biofiltration + Storage ☐ Selected BMPs have been designed to address the entire DCV. The DMA is compliant with Pollution Control BMP sizing requirements. STOP * ☐ Other (describe in discussion section below) ☐ Worksheet B.6-1 - Flow-thru treatment control with alternative compliance (provide BMP type/description in discussion section below) ☐ Describe in discussion section below why the remaining BMP size could not fit on site. ☐ Identification and Narrative of Receiving Water Pollutants of Concern ☐ Selection of Flow-Thru Treatment Control BMPs with high or medium effectiveness ☐ FT-1 Vegetated swales ☐ FT-2 Media Filters ☐ FT-3 Sand Filters ☐ FT-4 Dry Extended Detention Basin ☐ FT-5 Proprietary flow-thru treatment control ☐ Pollutant Control Offsite Alternative Compliance Participation form ☐ Water Quality Equivalency Worksheets20 PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS 19 Template Date: September 26, 2019 Preparation Date: September 14, 2020 Purpose: ☐ Pre-treatment/forebay for another structural BMP ☐ Pollutant control only ☐ Combined pollutant control and hydromodification control (see Attachment 2) ☐ Other (describe in discussion section below) Who will certify construction of this BMP? Provide name and contact information for the party responsible to sign BMP verification forms (See Chapter 1.12 of the BMP Design Manual) Who will be the final owner of this BMP? ☐ HOA ☐ Property Owner ☐ City ☐ Other (describe) Who will maintain this BMP into perpetuity? ☐ HOA ☐ Property Owner ☐ City ☐ Other (describe) Discussion (as needed): (Continue on subsequent pages as necessary) * If this box is checked, Worksheet B.6-1 does not need to be filled out. 20 PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS Preparation Date: September 14, 2020 Template Date: September 26, 2019 Identification and Narrative of Receiving Water and Pollutants of Concern Describe flow path of stormwater from the project site discharge location(s), through urban storm conveyance systems as applicable, to receiving creeks, rivers, and lagoons as applicable, and ultimate discharge to the Pacific Ocean (or bay, lagoon, lake or reservoir, as applicable): Local drainage to Temecula Creek to Santa Margarita River to Margarita Lagoon to the Pacific Ocean. List any 303(d) impaired water bodies 3 within the path of stormwater from the project site to the Pacific Ocean (or bay, lagoon, lake or reservoir, as applicable), identify the pollutant(s)/stressor(s) causing impairment, and identify any TMDLs and/or Highest Priority Pollutants from the WQIP for the impaired water bodies (see BMP Design Manual Appendix B.6.1): 303(d) Impaired Water Body Pollutant(s)/Stressor(s) TMDLs / WQIP Highest Priority Pollutant Temecula Creek Chlorpyrifos, Copper Indicator Bacteria, Total Dissolved Solids, Toxicity Santa Margarita River Indicator Bacteria, Iron, Manganese, Nitrogen Identification of Project Site Pollutants* *Identification of project site pollutants below is only required if flow-thru treatment BMPs are implemented onsite in lieu of retention or biofiltration BMPs. Note the project must also participate in an alternative compliance program (unless prior lawful approval to meet earlier PDP requirements is demonstrated). Identify pollutants expected from the project site based on all proposed use(s) of the site (see BMP Design Manual Appendix B.6.): Pollutant Not Applicable to the Project Site Anticipated from the Project Site Also a Receiving Water Pollutant of Concern Sediment ☐ ☐ ☐ Nutrients ☐ ☐ ☐ Heavy Metals ☐ ☐ ☐ Organic Compounds ☐ ☐ ☐ Trash & Debris ☐ ☐ ☐ Oxygen Demanding Substances ☐ ☐ ☐ Oil & Grease ☐ ☐ ☐ Bacteria & Viruses ☐ ☐ ☐ Pesticides ☐ ☐ ☐ 3 The current list of Section 303(d) impaired water bodies can be found at http://www.waterboards.ca.gov/water_issues/programs/water_quality_assessment/#impaired PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS 21 Template Date: September 26, 2019 Preparation Date: September 14, 2020 Attachment 1g: Offsite Alternative Compliance Participation Form - Pollutant Control Refer to Chapter 1.8 Onsite Project Information Record ID: Assessor's Parcel Number(s) [APN(s)] Quantity of Pollutant Control Debits or Credits (cubic feet) ☐ Debits ☐ Credits *See Attachment 1 of the PDP WQMP Offsite Project Information – Projects providing or receiving credits (add rows as needed) Record ID: APN(s) Project Owner/Address Credit/Debit Quantity (cubic feet) 1. ☐ Credit ☐ Debit 2. ☐ Credit ☐ Debit 3. ☐ Credit ☐ Debit 4. ☐ Credit ☐ Debit 5. ☐ Credit ☐ Debit 6. ☐ Credit ☐ Debit Total sum of Credits and Debits (∑Credits -∑Debits) (cubic feet) Additional Information Are offsite project(s) in the same credit trading area as the onsite project? ☐ Yes ☐ No Will projects providing credits be completed prior to completion of projects receiving credits? ☐ Yes ☐ No Are all deficits accounted for? If No, onsite and offsite projects must be redesigned to account for all deficits. ☐ Yes ☐ No Provide Alternative Compliance In-Lieu Fee Agreement and supporting WQE calculations as part of this attachment. A B SHO W A L T E R R O A D SH O W A L T E R R O A D 945-070-004 945-070-003 945-080-025 945-070-020 945-070-009 945-070-015 945-070-009 945-070-001 945-070-004 C EARTHEN BERM DETAIL APPROX SITE LOCATION 85TH=0.97 Category # Description i ii iii iv v vi vii viii ix x Units 1 Drainage Basin ID or Name DMA1 DMA2 DMA3 SRA unitless 2 85th Percentile 24-hr Storm Depth 2.43 2.43 2.43 0.97 inches 3 Impervious Surfaces Not Directed to Dispersion Area (C=0.90) 0 0 0 0 sq-ft 4 Semi-Pervious Surfaces Not Serving as Dispersion Area (C=0.30) 0 0 0 0 sq-ft 5 Engineered Pervious Surfaces Not Serving as Dispersion Area (C=0.10) 0 0 0 0 sq-ft 6 Natural Type A Soil Not Serving as Dispersion Area (C=0.10) 0 0 0 0 sq-ft 7 Natural Type B Soil Not Serving as Dispersion Area (C=0.14) 0 0 0 0 sq-ft 8 Natural Type C Soil Not Serving as Dispersion Area (C=0.23) 5,394 1,187 2,391 0 sq-ft 9 Natural Type D Soil Not Serving as Dispersion Area (C=0.30) 0 0 0 0 sq-ft 10 Does Tributary Incorporate Dispersion, Tree Wells, and/or Rain Barrels? Yes Yes Yes Yes No No No No No No yes/no 11 Impervious Surfaces Directed to Dispersion Area per SD-B (Ci=0.90) 9,743 1,042 3,067 1,255 sq-ft 12 Semi-Pervious Surfaces Serving as Dispersion Area per SD-B (Ci=0.30) 0 0 0 0 sq-ft 13 Engineered Pervious Surfaces Serving as Dispersion Area per SD-B (Ci=0.10) 3,640 9,850 10,042 3,013 sq-ft 14 Natural Type A Soil Serving as Dispersion Area per SD-B (Ci=0.10) 0 0 0 0 sq-ft 15 Natural Type B Soil Serving as Dispersion Area per SD-B (Ci=0.14) 0 0 0 0 sq-ft 16 Natural Type C Soil Serving as Dispersion Area per SD-B (Ci=0.23) 0 0 0 0 sq-ft 17 Natural Type D Soil Serving as Dispersion Area per SD-B (Ci=0.30) 0 0 0 0 sq-ft 18 Number of Tree Wells Proposed per SD-A 3 1 1 0 # 19 Average Mature Tree Canopy Diameter 20 20 20 0 ft 20 Number of Rain Barrels Proposed per SD-E 0 0 0 0 # 21 Average Rain Barrel Size 0 0 0 0 gal 22 Total Tributary Area 18,777 12,079 15,500 4,268 0 0 0 0 0 0 sq-ft 23 Initial Runoff Factor for Standard Drainage Areas 0.23 0.23 0.23 0.00 0.00 0.00 0.00 0.00 0.00 0.00 unitless 24 Initial Runoff Factor for Dispersed & Dispersion Areas 0.68 0.18 0.29 0.34 0.00 0.00 0.00 0.00 0.00 0.00 unitless 25 Initial Weighted Runoff Factor 0.55 0.18 0.28 0.34 0.00 0.00 0.00 0.00 0.00 0.00 unitless 26 Initial Design Capture Volume 2,091 440 879 117 0 0 0 0 0 0 cubic-feet 27 Total Impervious Area Dispersed to Pervious Surface 9,743 1,042 3,067 1,255 0 0 0 0 0 0 sq-ft 28 Total Pervious Dispersion Area 3,640 9,850 10,042 3,013 0 0 0 0 0 0 sq-ft 29 Ratio of Dispersed Impervious Area to Pervious Dispersion Area 2.70 0.10 0.30 0.40 n/a n/a n/a n/a n/a n/a ratio 30 Adjustment Factor for Dispersed & Dispersion Areas 0.15 0.00 0.00 0.00 1.00 1.00 1.00 1.00 1.00 1.00 ratio 31 Runoff Factor After Dispersion Techniques 0.14 0.02 0.04 0.00 n/a n/a n/a n/a n/a n/a unitless 32 Design Capture Volume After Dispersion Techniques 532 49 126 0 0 0 0 0 0 0 cubic-feet 33 Total Tree Well Volume Reduction 540 180 180 0 0 0 0 0 0 0 cubic-feet 34 Total Rain Barrel Volume Reduction 0 0 0 0 0 0 0 0 0 0 cubic-feet 35 Final Adjusted Runoff Factor 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 unitless 36 Final Effective Tributary Area 0 0 0 0 0 0 0 0 0 0 sq-ft 37 Initial Design Capture Volume Retained by Site Design Elements 2,099 571 933 117 0 0 0 0 0 0 cubic-feet 38 Final Design Capture Volume Tributary to BMP 0 0 0 0 0 0 0 0 0 0 cubic-feet False False Automated Worksheet B.1: Calculation of Design Capture Volume (V2.0) Dispersion Area, Tree Well & Rain Barrel Inputs (Optional) Standard Drainage Basin Inputs Results Tree & Barrel Adjustments Initial Runoff Factor Calculation Dispersion Area Adjustments No Warning Messages Category # Description i ii iii iv v vi vii viii ix x Units 1 Drainage Basin ID or Name DMA1 DMA2 DMA3 SRA - - - - - - unitless 2 85th Percentile Rainfall Depth 2.43 2.43 2.43 0.97 - - - - - - inches 3 Predominant NRCS Soil Type Within BMP Location C C C C unitless 4 Is proposed BMP location Restricted or Unrestricted for Infiltration Activities? Unrestricted Unrestricted Unrestricted Unrestricted unitless 5 Nature of Restriction n/a n/a n/a n/a unitless 6 Do Minimum Retention Requirements Apply to this Project?Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes yes/no 7 Are Habitable Structures Greater than 9 Stories Proposed?No No No No yes/no 8 Has Geotechnical Engineer Performed an Infiltration Analysis?Yes Yes Yes Yes yes/no 9 Design Infiltration Rate Recommended by Geotechnical Engineer 3.430 3.430 3.430 3.430 in/hr 10 Design Infiltration Rate Used To Determine Retention Requirements 3.430 3.430 3.430 3.430 - - - - - - in/hr 11 Percent of Average Annual Runoff that Must be Retained within DMA 80.0% 80.0% 80.0% 80.0% - - - - - - percentage 12 Fraction of DCV Requiring Retention 0.99 0.99 0.99 0.99 - - - - - - ratio 13 Required Retention Volume 0 0 0 0 - - - - - - cubic-feet False False Automated Worksheet B.2: Retention Requirements (V2.0) Advanced Analysis Basic Analysis Result No Warning Messages Category #Description i ii iii iv v vi vii viii ix x Units 1 Drainage Basin ID or Name DMA1 DMA2 DMA3 SRA ------sq-ft 2 Design Infiltration Rate Recommended 3.430 3.430 3.430 3.430 ------in/hr 3 Design Capture Volume Tributary to BMP 0 0 0 0 ------cubic-feet 4 Is BMP Vegetated or Unvegetated?Vegetated Vegetated Vegetated Vegetated unitless 5 Is BMP Impermeably Lined or Unlined?Unlined Unlined Unlined Unlined unitless 6 Does BMP Have an Underdrain?No Underdrain No Underdrain No Underdrain No Underdrain unitless 7 Does BMP Utilize Standard or Specialized Media?Standard Standard Standard Standard unitless 8 Provided Surface Area 1,390 422 504 3,013 sq-ft 9 Provided Surface Ponding Depth 4 4 4 4 inches 10 Provided Soil Media Thickness 30 30 30 30 inches 11 Provided Gravel Thickness (Total Thickness)0 0 0 0 inches 12 Underdrain Offset inches 13 Diameter of Underdrain or Hydromod Orifice (Select Smallest)inches 14 Specialized Soil Media Filtration Rate in/hr 15 Specialized Soil Media Pore Space for Retention unitless 16 Specialized Soil Media Pore Space for Biofiltration unitless 17 Specialized Gravel Media Pore Space unitless 18 Volume Infiltrated Over 6 Hour Storm 0 0 0 0 0 0 0 0 0 0 cubic-feet 19 Ponding Pore Space Available for Retention 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 unitless 20 Soil Media Pore Space Available for Retention 0.25 0.25 0.25 0.25 0.05 0.05 0.05 0.05 0.05 0.05 unitless 21 Gravel Pore Space Available for Retention (Above Underdrain)0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.40 unitless 22 Gravel Pore Space Available for Retention (Below Underdrain)0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.40 0.40 unitless 23 Effective Retention Depth 11.50 11.50 11.50 11.50 0.00 0.00 0.00 0.00 0.00 0.00 inches 24 Fraction of DCV Retained (Independent of Drawdown Time)0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 ratio 25 Calculated Retention Storage Drawdown Time 6 6 6 6 0 0 0 0 0 0 hours 26 Efficacy of Retention Processes 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 ratio 27 Volume Retained by BMP (Considering Drawdown Time)0 0 0 0 0 0 0 0 0 0 cubic-feet 28 Design Capture Volume Remaining for Biofiltration 0 0 0 0 0 0 0 0 0 0 cubic-feet 29 Max Hydromod Flow Rate through Underdrain 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 cfs 30 Max Soil Filtration Rate Allowed by Underdrain Orifice 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 in/hr 31 Soil Media Filtration Rate per Specifications 5.00 5.00 5.00 5.00 5.00 5.00 5.00 5.00 5.00 5.00 in/hr 32 Soil Media Filtration Rate to be used for Sizing 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 in/hr 33 Depth Biofiltered Over 6 Hour Storm 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 inches 34 Ponding Pore Space Available for Biofiltration 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 unitless 35 Soil Media Pore Space Available for Biofiltration 0.00 0.00 0.00 0.00 0.20 0.20 0.20 0.20 0.20 0.20 unitless 36 Gravel Pore Space Available for Biofiltration (Above Underdrain)0.00 0.00 0.00 0.00 0.40 0.40 0.40 0.40 0.40 0.40 unitless 37 Effective Depth of Biofiltration Storage 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 inches 38 Drawdown Time for Surface Ponding 1 1 1 1 0 0 0 0 0 0 hours 39 Drawdown Time for Effective Biofiltration Depth 0 0 0 0 0 0 0 0 0 0 hours 40 Total Depth Biofiltered 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 inches 41 Option 1 - Biofilter 1.50 DCV: Target Volume 0 0 0 0 0 0 0 0 0 0 cubic-feet 42 Option 1 - Provided Biofiltration Volume 0 0 0 0 0 0 0 0 0 0 cubic-feet 43 Option 2 - Store 0.75 DCV: Target Volume 0 0 0 0 0 0 0 0 0 0 cubic-feet 44 Option 2 - Provided Storage Volume 0 0 0 0 0 0 0 0 0 0 cubic-feet 45 Portion of Biofiltration Performance Standard Satisfied 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 ratio 46 Do Site Design Elements and BMPs Satisfy Annual Retention Requirements?Yes Yes Yes Yes ------yes/no 47 Overall Portion of Performance Standard Satisfied (BMP Efficacy Factor)0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 ratio 48 Deficit of Effectively Treated Stormwater n/a n/a n/a n/a n/a n/a n/a n/a n/a n/a cubic-feet Biofiltration Calculations False False False False Result False False No Warning Messages Retention Calculations Automated Worksheet B.3: BMP Performance (V2.0) False False BMP Inputs Perc Test No. Date:3/12/2020 LD19-3729 The conversion equation is used: r =6.00 inches w =0.00 inches req = 0.00 inches Time interval Δt =60.0 minutes Initial height of water during selected time interval Ho = 8.00 inches Final height of water during selected time interval Hf = 0.00 inches Change in height of water during selected time interval ΔH =8.00 inches Average head height over the selected time interval Havg = 4.00 inches Converted infiltration rate per test data It = 3.43 inches/hour County/City Case No: ΔH(in) x 60 (min/hr) x r(in) Δt(min) x [r(in) + 2Havg(in)] Company Name: Legend: Percolation Conversion to Infiltration Rate Porchet Method - Conversion of Percolation Rate to Infiltration Rate Designed by: Robert Ventura Engineering Inland, Inc Required Entries Calculated Cells If test hole is round - Enter radius here If test hole is square - Enter average side width below It (in/hr) = Comments PRELIMINARY DRAFT ‐ SUBJECT TO REVISION (MAY 2010) APPROXIMATE SITE LOCATION MC GOVERN RESIDENCE 902.32 SANTA MARGARITA HU MURRIETA HA MURRIETA HSA LONG CANYON WATERSHED LOCATION MAP Table 2-2. BENEFICIAL USES OF INLAND SURFACE WATERS ● Existing Beneficial Use 1 Waterbodies are listed multiple times if they cross hydrologic area or sub area boundaries. ○ Potential Beneficial Use 2 Beneficial use designations apply to all tributaries to the indicated waterbody, if not listed separately. + Excepted from MUN (See Text) Table 2-2 BENEFICIAL USES 2 - 21 BENEFICIAL USE Inland Surface Waters 1, 2 Hydrologic Unit Basin Number M U N A G R I N D P R O C G W R F R S H P O W R E C 1 R E C 2 B I O L W A R M C O L D W I L D R A R E S P W N San Onofre Creek Watershed – continued Las Flores Creek 1.52 +● ● ● ●●● ● Piedra de Lumbre Canyon 1.52 +● ● ● ●●● ● unnamed intermittent coastal streams 1.52 +● ● ● ● ● Aliso Canyon 1.53 +● ● ● ●●● ● French Canyon 1.53 +● ● ● ● ● ● Cockleburr Canyon 1.53 +● ● ● ● ● Santa Margarita River Watershed Santa Margarita River 2.22 ● ● ● ● ● ● ● ● ● Murrieta Creek 2.31 ● ● ● ● ○ ● ● ● Bundy Canyon 2.31 ● ● ● ● ○ ● ● ● Slaughterhouse Canyon 2.31 ● ● ● ● ○ ● ● ● Murrieta Creek 2.32 ● ● ● ● ○ ● ● ● Murrieta Creek 2.52 ● ● ● ● ● ○ ● ● ● Cole Canyon 2.32 ● ● ● ● ○ ● ●● ● Miller Canyon 2.32 ● ● ● ● ○ ● ● ● Warm Springs Creek 2.36 ● ● ● ● ○ ● ● ● Diamond Valley 2.36 ● ● ● ● ○ ● ● ● Table 2-2. BENEFICIAL USES OF INLAND SURFACE WATERS ● Existing Beneficial Use 1 Waterbodies are listed multiple times if they cross hydrologic area or sub area boundaries. ○ Potential Beneficial Use 2 Beneficial use designations apply to all tributaries to the indicated waterbody, if not listed separately. 3 Rainbow Creek is designated as an impaired water body for total nitrogen and total phosphorus pursuant to Clean Water Act section 303(d). Total Maximum Daily Loads (TMDLs) have been adopted to address these impairments. See Chapter 3, Water Quality Objectives for Biostimulatory Substances and Chapter 4, Total Maximum Daily Loads. Table 2-2 BENEFICIAL USES 2 - 25 BENEFICIAL USE Inland Surface Waters 1, 2 Hydrologic Unit Basin Number M U N A G R I N D P R O C G W R F R S H P O W R E C 1 R E C 2 B I O L W A R M C O L D W I L D R A R E S P W N Santa Margarita River Watershed - continued Temecula Creek 2.51 ● ● ● ● ● ○ ● ● ● Temecula Creek 2.52 ● ● ● ● ● ○ ● ● ● Pechanga Creek 2.52 ● ● ● ● ● ○ ● ● ● Rainbow Creek3 2.23 ● ● ● ● ● ● ● ● ● Rainbow Creek3 2.22 ● ● ● ● ● ● ● ● ● Sandia Canyon 2.22 ● ● ● ● ● ● ● ● ● Walker Basin 2.22 ● ● ● ● ● ● ● ● Santa Margarita River 2.21 ● ● ● ● ● ● ● ● ● DeLuz Creek 2.21 ● ● ● ● ● ● ● ● ● ● Cottonwood Creek 2.21 ● ● ● ● ● ● ● ● Camps Creek 2.21 ● ● ● ● ● ● ● ● ● Fern Creek 2.21 ● ● ● ● ● ● ● ● ● Roblar Creek 2.21 ● ● ● ● ● ● ● ● O’Neill Lake 2.13 See Reservoirs & Lakes – Table 2-4 Santa Margarita River 2.13 ● ● ● ● ● ● ● ● ● ● Wood Canyon 2.13 ● ● ● ● ● ● ● ● Santa Margarita River 2.12 ● ● ● ● ● ● ● ● ● ● Table 2-2. BENEFICIAL USES OF INLAND SURFACE WATERS ● Existing Beneficial Use 1 Waterbodies are listed multiple times if they cross hydrologic area or sub area boundaries. 2 Beneficial use designations apply to all tributaries to the indicated waterbody, if not listed separately. Table 2-2 BENEFICIAL USES 2 - 26 BENEFICIAL USE Inland Surface Waters 1, 2 Hydrologic Unit Basin Number M U N A G R I N D P R O C G W R F R S H P O W R E C 1 R E C 2 B I O L W A R M C O L D W I L D R A R E S P W N Santa Margarita River Watershed - continued Santa Margarita River 2.11 ● ● ● ● ● ● ● ● ● ● Pueblitos Canyon 2.11 ● ● ● ● ● ● ● ● ● Newton Canyon 2.11 ● ● ● ● ● ● ● ● Santa Margarita Lagoon 2.11 See Coastal Waters – Table 2-3 San Luis Rey River Watershed San Luis Rey River 3.32 ● ● ● ● ● ● ● ● ● ● Johnson Canyon 3.32 ● ● ● ● ● ● ● ● ● ● San Luis Rey River 3.31 ● ● ● ● ● ● ● ● ● ● Canada Aguanga 3.31 ● ● ● ● ● ● ● ● ● ● Dark Canyon 3.31 ● ● ● ● ● ● ● ● ● ● Bear Canyon 3.31 ● ● ● ● ● ● ● ● ● ● Cow Canyon 3.31 ● ● ● ● ● ● ● ● ● ● Blue Canyon 3.31 ● ● ● ● ● ● ● ● ● ● Rock Canyon 3.31 ● ● ● ● ● ● ● ● ● ● Agua Caliente Creek 3.31 ● ● ● ● ● ● ● ● ● ● unnamed Tributary 3.31 ● ● ● ● ● ● ● ● ● ● ● Canada Agua Caliente 3.31 ● ● ● ● ● ● ● ● ● ● Table 2-3. BENEFICIAL USES OF COASTAL WATERS 1 Includes the tidal prisms of the Otay and Sweetwater Rivers. 2 Fishing from shore or boat permitted, but other water contact recreational (REC-1) uses are prohibited. 3 The Shelter Island Yacht Basin portion of San Diego Bay is designated as an impaired water body for dissolved copper pursuant to Clean Water Act section 303(d). 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. ● Existing Beneficial Use Table 2-3 2 - 52 BENEFICIAL USES BENEFICIAL USE Coastal Waters Hydrologic Unit Basin Number I N D N A V R E C 1 R E C 2 C O M M B I O L E S T W I L D R A R E M A R A Q U A M I G R S P W N W A R M S H E L L Pacific Ocean ●●●●●● ● ●●● ●● ● Dana Point Harbor ●●●●● ● ●● ●● ● Del Mar Boat Basin ●●●●● ● ●● ●● ● Mission Bay ● ●●● ●● ●● ●● ● Oceanside Harbor ●●●●● ● ●● ●● ● San Diego Bay 1, 3 ●●●●●● ●● ●● ●● ● Coastal Lagoons Tijuana River Estuary 11.11 ●●●● ●● ●● ●● ● Mouth of San Diego River 7.11 ●●● ●● ●● ●● ● Famosa Slough and Channel 7.11 ●●● ●● ●● ●● ● Los Penasquitos Lagoon 2 6.10 ●● ● ●● ●● ●● ● San Dieguito Lagoon 5.11 ●● ● ●● ●● ●● Batiquitos Lagoon 4.51 ●● ● ●● ●● ●● San Elijo Lagoon 4.61 ●● ● ●● ●● ●● Agua Hedionda Lagoon 4.31 ● ●●●● ●● ●●● ●● ● Table 2-3. BENEFICIAL USES OF COASTAL WATERS 2 Fishing from shore or boat permitted, but other water contact recreational (REC-1) uses are prohibited. ● Existing Beneficial Use ○ Potential Beneficial Use BENEFICIAL USE S Hydrologic Unit Basin Number R R E C 2 C O M M B W R A M S W I N E M H E I I A Q I P A Coastal Waters N A S A E C O L L R U G W R D V T R L 1 D E A R N M L Coastal Lagoons - continued ●● ● ○● ●● ● 2 Buena Vista Lagoon 4.21 ●● ●● ●● Loma Alta Slough 4.10 ●● ● ●● ● Mouth of San Luis Rey River 3.11 ●● ●● ●● ●● Santa Margarita Lagoon 2.11 ●● ● ●● Aliso Creek Mouth 1.13 ●● ● ●● ● ● San Juan Creek Mouth 1.27 ●● ● ● ●● ●● San Mateo Creek Mouth 1.40 ●● ● ●● ●● San Onofre Creek Mouth 1.51 Table 2-3 2 - 53 BENEFICIAL USES Table 2-5. BENEFICIAL USES OF GROUND WATERS 2 These beneficial uses do not apply westerly of the right-of-way of Interstate 5 and this area is excepted from the sources of drinking water policy. The beneficial uses for the remainder of the hydrologic area are as shown. ● Existing Beneficial Use BENEFICIAL USE Ground Water Hydrologic Unit Basin Number M U N A G R I N D P R O C F R S H G W R SANTA MARGARITA HYDROLOGIC UNIT 2.00 Ysidora HA 2 2.10 ● ● ● ● DeLuz HA 2.20 ● ● ● Murrieta HA 2.30 ● ● ● ● Auld HA 2.40 ● ● ● Pechanga HA 2.50 ● ● ● Wilson HA 2.60 ● ● ○ Cave Rocks HA 2.70 ● ● Aguanga HA 2.80 ● ● ● Oakgrove HA 2.90 ● ● ○ Potential Beneficial Use Table 2-5 BENEFICIAL USES 2 - 58 SD-A Tree Well www.sandiegocounty.gov/stormwater E-28 Effective January 1, 2019 E.7 SD-A Tree Wells Tree Wells (Source: County of San Diego LID Manual – EOA, Inc.) Description Trees planted to intercept rainfall and runoff as described in this fact sheet may be used as storm water management measures to provide runoff reduction of the DCV per Appendix B.1.4. Additional benefits associated with tree wells, include energy conservation, air quality improvement, and aesthetic enhancement. In addition to the requirements provided in this fact sheet, tree wells located in the County Right-of-Way shall follow requirements in Appendix K of this manual. Deviations from the outlined criteria ay be approved at the discretion of County staff. Typical storm water management benefits associated with trees include: •Interception of rainfall – tree surfaces (roots, foliage, bark, and branches) intercept, evaporate, store, or convey precipitation to the soil before it reaches surrounding impervious surfaces •Reduced erosion – trees protect denuded area by intercepting or reducing the velocity of rain drops as they fall through the tree canopy •Increased infiltration – soil conditions created by roots and fallen leaves promote infiltration •Treatment of storm water – trees provide treatment through uptake of nutrients and other storm water pollutants (phytoremediation) and support of other biological processes that break down pollutants MS4 Permit Category Site Design Retention Manual Category Site Design Infiltration Applicable Performance Standard Site Design Pollutant Control Flow Control Primary Benefits Volume Reduction SD-A Tree Well www.sandiegocounty.gov/stormwater E-29 Effective January 1, 2019 Typical tree well system components include: •Trees of the appropriate species for site conditions and constraints. Refer to the Plant List in this fact sheet. •Available soil media reservoir volume based on mature tree size, soil type, water availability, surrounding land uses, and project goals •Optional suspended pavement design to provide structural support for adjacent pavement without requiring compaction of underlying layers •Optional root barrier devices as needed; a root barrier is a device installed in the ground, between a tree and the sidewalk, intended to guide roots down and away from the sidewalk in order to prevent sidewalk lifting from tree roots. •Optional tree grates; to be considered to maximize available space for pedestrian circulation and to protect tree roots from compaction related to pedestrian circulation; tree grates are typically made up of porous material that will allow the runoff to soak through. •Optional shallow surface depression for ponding of excess runoff •Optional planter box drain Design Adaptations for Project Goals Site design BMP to provide incidental treatment. Tree wells primarily function as site design BMPs for incidental treatment. Pollutant Control BMP to provide treatment. Project proponents are allowed to design trees to reduce the volume of stormwater runoff that requires treatment, (the Design Capture Volume [DCV]), or completely fulfill the pollutant control BMP requirements by retaining the entire DCV. Benefits from tree wells are accounted for by using the volume reduction values in Table B.1-3 presented in Appendix B. This credit can apply to other trees that are used for landscaping purposes that meet the same criteria. Project proponents are required to provide calculations supporting the amount of credit claimed from implementing trees within the project footprint. Flow Control BMP to meet hydromodification requirements. Project proponents are also allowed to design tree wells as a flow control BMP. Benefits from tree wells are accounted for by using the Schematic of Tree Well SD-A Tree Well www.sandiegocounty.gov/stormwater E-30 Effective January 1, 2019 DCV multipliers listed below. Project proponents are required to provide calculations showing that the entire DCV including the DCV multiplier is retained. Design Criteria and Considerations Tree Wells, whether designed as Site Design BMPs, as Stormwater Pollutant Control BMP, or as a Flow Control BMP must meet the following design criteria and considerations, and if placed in the right-of-way must be consistent with the County of San Diego Green Streets Design Criteria and Green Streets Standard Drawings in Appendix K. Deviations from the below criteria may be approved at the discretion of the County staff if it is determined to be appropriate: Siting and Design Intent/Rationale □ Tree species is appropriately chosen for the development (private or public). For public rights-of-ways, local planning guidelines and zoning provisions for the permissible species and placement of trees are consulted. A list of trees appropriate for site design that can be used by all county municipalities are provided in this fact sheet. Proper tree placement and species selection minimizes problems such as pavement damage by surface roots and poor growth. □ Tree well placement: ensure area is graded; and the well is located so that full amount of DCV reduction drains to the well. Minimizes short-circuiting of run off and assures DCV reductions are retained onsite. SD-A Tree Well www.sandiegocounty.gov/stormwater E-31 Effective January 1, 2019 Siting and Design Intent/Rationale □ Location of trees planted along public streets follows guidance on green infrastructure (Appendix K). Vehicle and pedestrian line of sight and clear recovery zones are considered in tree selection and placement. Unless exemption is granted by County staff the following minimum tree separation distance is followed Improvement Minimum distance to tree well Traffic Signal, Stop sign 20 feet Underground Utility lines (except sewer) 5 feet Sewer Lines 10 feet Above ground utility structures (Transformers, Hydrants, Utility poles, etc.) 10 feet Driveways 10 feet Intersections (intersecting curb lines of two streets) 25 feet Roadway safety for both vehicular and pedestrian traffic is a key consideration for placement along public streets. □ Underground utilities and overhead wires are considered in the design and avoided or circumvented. Underground utilities are routed around or through the planter in suspended pavement applications. All underground utilities are protected from water and root penetration. Tree growth can damage utilities and overhead wires resulting in service interruptions. Protecting utilities routed through the planter prevents damage and service interruptions. Refer to Section 6.6 of the Green Streets Design Criteria in Appendix K for guidelines regarding utility placement and potential conflict with BMP facilities. □ Suspended pavement was used for confined Tree Well soil volume. Suspended pavement design was developed where appropriate to minimize soil compaction and improve infiltration and filtration capabilities. Suspended pavement designs as shown in Page 7 of the Green Streets Guidelines in Appendix K provide structural support without compaction of the underlying layers, thereby promoting tree growth. SD-A Tree Well www.sandiegocounty.gov/stormwater E-32 Effective January 1, 2019 Siting and Design Intent/Rationale Suspended pavement was constructed with an approved structural cell. Recommended structural cells include poured in place concrete columns, Silva Cells manufactured by Deeproot Green Infrastructures and Stratacell and Stratavault systems manufactured by Citygreen Systems. □ A minimum soil volume of 2 cubic feet per square foot of mature tree canopy projection area is provided for each tree. Canopy projection area is the ground area beneath the mature tree, measured at the drip line. Soil volume must be within 1.5 times the mature tree canopy radius. Soil depth shall be a minimum of 30 inches deep, preferably 36 inches deep. When placing tree well next to curb use Structural Soil as outlined in the section below titled “Confined Tree Well Soil Volume” and use Specifications in Appendix K Use Amended Soil per Fact Sheet SD-F in all other cases. The minimum soil volume ensures that there is adequate storage volume to allow for unrestricted evapotranspiration and infiltration. A lower amount of soil volume may be allowed at the discretion of County staff if certified by a landscape architect or agronomist. The retention credit from the tree is directly proportional to the soil volume provided for the tree. □ To claim credit for existing trees, the root structure of existing tree shall be protected and additional soil volumes provided to meet the above requirements. A berm or well must be constructed around the perimeter of the soil volume to be credited and an inlet structure must be of the appropriate size to allow runoff to enter the well. Considerations should be made to prevent root and water intrusion damage to surrounding infrastructure. The minimum soil volume ensures that there is adequate storage volume to allow for unrestricted storage, evapotranspiration, and infiltration. A lower amount of soil volume may be allowed at the discretion of County staff if certified by a landscape architect or agronomist. The retention credit from the tree is directly proportional to the soil volume provided for the tree. □ DCV from the tributary area draining to the tree is equal to or greater than the tree credit volume The minimum tributary area ensures that the tree receives enough runoff to fully utilize the infiltration and evapotranspiration potential provided. In cases where the minimum tributary area is not provided, the tree credit volume SD-A Tree Well www.sandiegocounty.gov/stormwater E-33 Effective January 1, 2019 Siting and Design Intent/Rationale must be reduced proportionately to the actual tributary area. □ Inlet opening to the tree that is at least 18 inches wide. A minimum 2 inch drop in grade from the inlet to the finish grade of the tree. Grated inlets are allowed for pedestrian circulation. Grates need to be ADA compliant and have sufficient slip resistance. Design requirement to ensure that the runoff from the tributary area does not bypass the BMP. Different inlet openings and drops in grade may be allowed at the discretion of County staff if calculations are shown that the diversion flow rate (Appendix B.) from the tributary area can be conveyed to the tree. In cases where the inlet capacity is limiting the amount of runoff draining to the tree, the tree credit volume must be reduced proportionately. Conceptual Design and Sizing Approach for Site Design Determine the areas where tree wells can be used in the site design to achieve incidental treatment. Tree wells reduce runoff volumes from the site. Refer to Appendix B.2. Document the proposed tree locations in the SWQMP. Conceptual Design and Sizing Approach for Pollutant Control When trees are proposed as a storm water pollutant control BMP, the project proponent must submit detailed calculations for the DCV treated by trees. Document the proposed tree locations on the BMP Plan & DMA Map, and provide sizing calculations in the SWQMP Attachment following the steps in Appendix B. Conceptual Design and Sizing Approach for Flow Control When trees are proposed as a flow control BMP, the project proponent must submit detailed calculations for the Required Retention Volume (RRV) treated by trees. Document the proposed tree locations on the BMP Plan & DMA Map, and provide sizing calculations in the SWQMP Attachment. Tree Wells that are designed to meet flow control requirements are designated as SSD BMPs. 1.Determine how much volume you need. The Required Retention Volume (RRV) is the volume of rainfall that must be retained by the tree wells in the DMA to meet flow control requirements. It is calculated by multiplying the DCV by a DCV multiplier. SD-A Tree Well www.sandiegocounty.gov/stormwater E-34 Effective January 1, 2019 a.Determine the DCV. See Appendix B. b.Determine the DCV Multiplier. The DCV Multiplier is based on two factors: (1) The tree well soil depth and, (2) The Hydrologic Soil Group. Once you know both values, determine the DCV Multiplier using this table: c.Calculate the Required Retention Volume (DCV x DCV Multiplier). Calculate the RRV by multiplying the DCV by the DCV Multiplier. This is the volume of runoff that must be offset by the Tree Well Credit Volume. Repeat this process for each DMA. DCV Multiplier Table Tree Well Soil Depth is the vertical distance from the top to the bottom of the soil layer in the tree well. Hydrologic Soil Group describes the native soil surrounding the tree well. Soil type affects how well water can infiltrate into the area surrounding the tree well. Group A soils provide the most infiltration and Group D the least. If your soil type is unknown, you can assume Group D. But this will result in larger DCV Multipliers, and in turn increase the size or number of tree wells needed. Alternative Proposals: You can also propose RRV values or use methods and assumptions different than those described here. Proposals must be based on SWMM modeling or other methods acceptable to the County. 2.Determine how much volume you have. The Tree Well Credit Volume is the volume of runoff retention in cubic feet per tree (ft3/tree) to be provided by each tree well (or group) in the DMA. Together retain a volume that is equal to or greater than the RRV for the DMA. The volume credited for each tree well is based on the mature canopy diameter of the tree species selected. Any species listed below can be used in a tree well so long as it meets all other applicable restrictions and requirements for the project area. Native and drought tolerant species are required where feasible. SD-A Tree Well www.sandiegocounty.gov/stormwater E-35 Effective January 1, 2019 Botanical Name Common Name Mature Height (ft) Mature Canopy Diameter (ft) Credit Volume per Tree (ft3) 1 Ceanothus ‘Ray Hartman” California Mountain Lillac 30 10 40 2 Pittosporum Phillyraeoides Willow Pittosporum 25 15 100 3 Salix Lasiolepsis Arroyo Willow 25 4 Arbutus Unedo Strawberry Tree 30 20 180 5 Prunus Ilicifolia Hollyleaf Cherry 30 6 Prunus Lynoii Catalina Cherry 40 7 Cercis Occidentalis Western Redbud 25 25 290 8 Heteromeles Arbutifolia Toyon, Christmas Berry 25 9 Alnus Rhombifolia White Elder 75 30 420 10 Arbutus ‘Marina’ Hybrid Strawberry Tree 35 11 Chilopsis Linearis Desert Willow 30 12 Lyonothamnus Floribundus Catalina Ironwood 50 13 Magnolia Grandiflora Southern Magnolia 40 14 Pinus Torreyana Torrey Pines 80 15 Platanus Racemosa California sycamore 60 16 Quercus Agrifolia Coast Live Oak 70 17 Quercus Engelmannii Engelmann Oak 50 18 Quercus Suber Cork Oak 40 19 Sambucus Mexicana Blue Elderberry 30 Tree Palette Table Below are sources for Tree Palette Mature Height and Mature Canopy Diameter: A.Water Efficient Landscape Design Manual, County of San Diego, 2016 B.Sustainable Landscapes Guidelines, San Diego County Water Authority, 2015 C.Low Impact Development Handbook, County of San Diego, 2014 D.Low Impact Development Design Manual, City of San Diego, 2011 E. Street Tree Selection Guide, City of San Diego, 2013 F.Environmentally Friendly Garden Plant List, City of San Diego, 2004 G.BMP Design Manual, County of San Diego, 2016 H.California Native Plant Society. 2017 Alternative Species. Tree species other than those listed are allowable, but must be approved by the SD-A Tree Well www.sandiegocounty.gov/stormwater E-36 Effective January 1, 2019 County. If you know the mature canopy diameter of the species you want to propose, use the values in the table to determine its credit volume. Note that even if you select a species with a canopy diameter greater than 30 feet, the maximum credit any tree can generate is 420 ft3. 3.Determine if you have enough volume. Compare your total Tree Well Credit Volume from Step 2 to the RRV you calculated in Step 1. Once your Credit Volume is equal to or greater than your RRV, this requirement is satisfied. If your Credit Volume is initially too low, adjust your design either to (1) increase it with more or bigger trees, or (2) decrease the RRV through DCV reductions. Tree wells will normally be placed at the discharge point of the DMA, either individually or in groups. If some of them will retain runoff from different areas in the DMA, RRV and DCV calculations must be specific to each subarea. SD-A Tree Well www.sandiegocounty.gov/stormwater E-37 Effective January 1, 2019 Tree Planting Design in New or Reconstructed Streetscapes 1.Maximized open soil area for tree planting is the most cost effective method of achieving the required soil volume. 2.Tree wells within sidewalks shall have a minimum open area of four feet wide by six feet long. Larger areas may be required to accommodate large root balls. 3. Tree well soil characteristics shall meet the requirements of SD-F Amended Soil. Structural Requirements for Confined Tree Well Soil Volume In order to provide adequate soil volume for tree wells, soils may be placed confined beneath adjacent paved surfaces. Acceptable soil systems capable of carrying D-50 loading include structural soils, structural slabs, and structural cells: 1.Structural soil systems include CU-StructuralSoilTM, Stalite Structural Soil, or equivalent. 2.Suspended pavements that allow uncompacted growing soil beneath the sidewalk include; structural slabs that span between structural supports, structural cells, and other commercially available structural systems. See Page 7 of the Green Streets Guidelines in Appendix K for illustrations. Manufacturer details and certification must be provided for commercial systems. Structural calculations and details must be provided for structural slab installations. Structural cells are commercially-available structural systems placed subsurface that support the sidewalk and are filled with amended soil (SD-F). Manufacturer details and certification must be provided for commercial systems. Stormwater Retention and Treatment Volume Tree wells with expanded soil volume will serve as a method of capturing and retaining the required volume of stormwater in accordance with County requirements in Appendix B of this manual. These facilities can be designed to meet the County requirements when surface ponding volume is provided, whether designed as an enclosed plant bed with covered soil volume, or a continuous open area (either mulched or with turf) with soil volume under the adjacent sidewalk. Maintenance Overview Normal Expected Maintenance. Tree health shall be maintained as part of normal landscape maintenance. Additionally, ensure that storm water runoff can be conveyed into the tree well as designed. That is, the opening that allows storm water runoff to flow into the tree well (e.g., a curb opening, tree grate, or surface depression) shall not be blocked, filled, re-graded, or otherwise changed in a manner that prevents storm water from draining into the tree well. A summary table of standard inspection and maintenance indicators is provided within this Fact Sheet. SD-A Tree Well www.sandiegocounty.gov/stormwater E-38 Effective January 1, 2019 Non-Standard Maintenance or BMP Failure. Trees wells are site design BMPs that normally do not require maintenance actions beyond routine landscape maintenance. The normal expected maintenance described above ensures the BMP functionality. If changes have been made to the tree well entrance / opening such that runoff is prevented from draining into the tree well (e.g., a curb inlet opening is blocked by debris or a grate is clogged causing runoff to flow around instead of into the tree well, or a surface depression has been filled so runoff flows away from the tree well), the BMP is not performing as intended to protect downstream waterways from pollution and/or erosion. Corrective maintenance will be required to restore drainage into the tree well as designed. Surface ponding of runoff directed into tree wells is expected to infiltrate/evapotranspirate within 24- 96 hours following a storm event. Surface ponding longer than approximately 24 hours following a storm event may be detrimental to vegetation health, and surface ponding longer than approximately 96 hours following a storm event poses a risk of vector (mosquito) breeding. Poor drainage can result from clogging or compaction of the soils surrounding the tree. Loosen or replace the soils to restore drainage. Other Special Considerations. Site design BMPs, such as tree wells, installed within a new development or redevelopment project are components of an overall storm water management strategy for the project. The presence of site design BMPs within a project is usually a factor in the determination of the amount of runoff to be managed with structural BMPs (i.e., the amount of runoff expected to reach downstream retention or biofiltration basins that process storm water runoff from the project as a whole). When site design BMPs are not maintained or are removed, this can lead to clogging or failure of downstream structural BMPs due to greater delivery of runoff and pollutants than intended for the structural BMP. Therefore, the County Engineer may require confirmation of maintenance of site design BMPs as part of their structural BMP maintenance documentation requirements. Site design BMPs that have been installed as part of the project should not be removed, nor should they be bypassed by re-routing roof drains or re- grading surfaces within the project. If changes are necessary, consult the County Engineer to determine requirements. SD-A Tree Well www.sandiegocounty.gov/stormwater E-39 Effective January 1, 2019 This page was left intentionally blank. SD-A Tree Wells www.sandiegocounty.gov/stormwater E-40 January 1, 2019 Summary of Standard Inspection and Maintenance The property owner is responsible to ensure inspection, operation and maintenance of permanent BMPs on their property unless responsibility has been formally transferred to an agency, community facilities district, homeowners association, property owners association, or other special district. Maintenance frequencies listed in this table are average/typical frequencies. Actual maintenance needs are site-specific, and maintenance may be required more frequently. Maintenance must be performed whenever needed, based on maintenance indicators presented in this table. The BMP owner is responsible for conducting regular inspections to see when maintenance is needed based on the maintenance indicators. During the first year of operation of a structural BMP, inspection is recommended at least once prior to August 31 and then monthly from September through May. Inspection during a storm event is also recommended. After the initial period of frequent inspections, the minimum inspection and maintenance frequency can be determined based on the results of the first year inspections. Threshold/Indicator Maintenance Action Inspection and Maintenance Frequency Tree health Routine actions as necessary to maintain tree health. • Inspect monthly. • Maintain when needed. Dead or diseased tree Remove dead or diseased tree. Replace per original plans. • Inspect monthly. • Maintain when needed. Standing water in tree well for longer than 24 hours following a storm event Surface ponding longer than approximately 24 hours following a storm event may be detrimental to tree health Loosen or replace soils surrounding the tree to restore drainage. • Inspect monthly and after every 0.5-inch or larger storm event. If standing water is observed, increase inspection frequency to after every 0.1-inch or larger storm event. • Maintain when needed. Presence of mosquitos/larvae For images of egg rafts, larva, pupa, and adult mosquitos, see http://www.mosquito.org/biology Disperse any standing water from the tree well to nearby landscaping. Loosen or replace soils surrounding the tree to restore drainage (and prevent standing water). • Inspect monthly and after every 0.5-inch or larger storm event. If mosquitos are observed, increase inspection frequency to after every 0.1-inch or larger storm event. • Maintain when needed SD-A Tree Wells www.sandiegocounty.gov/stormwater E-41 January 1, 2019 Threshold/Indicator Maintenance Action Inspection and Maintenance Frequency Entrance / opening to the tree well is blocked such that storm water will not drain into the tree well (e.g., a curb inlet opening is blocked by debris or a grate is clogged causing runoff to flow around instead of into the tree well; or a surface depression is filled such that runoff drains away from the tree well) Make repairs as appropriate to restore drainage into the tree well. • Inspect monthly. • Maintain when needed. 22 PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS Preparation Date: September 14, 2020 Template Date: September 26, 2019 ATTACHMENT 2 HYDROMODIFICATION CONTROL MEASURES Indicate which Items are Included behind this cover sheet: Attachment Sequence Contents Checklist Attachment 2a Do Hydromodification Management Requirements apply? See Chapter 1.6 and Figure 1-2. ☒ Hydromodification management controls required. ☐ Green Streets Project (Exempt from hydromodification management requirements) STOP * ☐ Exempt from hydromodification management requirements ☐ Include Figure 1-2 and document any “NO” answer STOP * Attachment 2b HMP Exhibits (Required) See Checklist on the back of this Attachment cover sheet. see Chapter 6.3.1 ☒ Combined with DMA Exhibit ☐ Included Attachment 2c Management of Critical Coarse Sediment Yield Areas See Chapter 6.2 and Appendix H of the BMP Design Manual. ☒ Exhibit depicting onsite/ upstream CCSYAs (Figure H.1-1) AND, documentation that project avoids CCSYA per Appendix H.1. OR ☐ Sediment Supply BMPs implemented. Attachment 2d Structural BMP Design Calculations, Drawdown Calculations, & Overflow Design. See Chapter 6 & Appendix G of the BMP Design Manual ☐ Included ☒ Project is designed entirely with De-Minimus, Self–Mitigating, and/or qualifying Self-Retaining Areas. STOP * Attachment 2e Geomorphic Assessment of Receiving Channels. See Chapter 6.3.4 of the BMP Design Manual. ☐ low flow threshold is 0.1Q2 ☐ low flow threshold is 0.3Q2 ☐ low flow threshold is 0.5Q2 Attachment 2f Vector Control Plan (Required when structural BMPs will not drain in 96 hours) ☐ Included ☐ Not required because BMPs will drain in less than 96 hours Attachment 2g Hydromodification Offsite Alternative Compliance form. Refer to Figure 1- 3: Pathways to Participating in Offsite Alternative Compliance Program ☐ Full Compliance Onsite ☐ Offsite ACP. Document onsite structural BMPs and complete Hydromodification Offsite Alternative Compliance Participation Form, and WQE worksheets * If this box is checked, the remainder of Attachment 2 does not need to be filled out. PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS 23 Template Date: September 26, 2019 Preparation Date: September 14, 2020 Use this checklist to ensure the required information has been included on the Hydromodification Management Exhibit: ☒ Point(s) of Compliance with name or number ☒ Project Site Boundary ☒ Project Disturbed Area Footprint ☒ Drainage management area (DMA) boundaries, DMA ID numbers, DMA areas (square footage or acreage), and DMA type (i.e., drains to structural BMP, self-retaining, self- mitigating, or de-minimis) Note on exhibit De-minimis areas and reason they could not be included. Include offsite areas receiving treatment to mitigate Onsite Water Quality Equivalency. ☐ Potential pollutant source areas and corresponding required source control BMPs (see Chapter 4, Appendix E.1, and Step 3.5) ☒ Proposed Site Design BMPs and surface treatments used to minimize imperviousness. Show sections, details, and dimensions of site design BMP’s (tree wells, dispersion areas, rain gardens, permeable pavement, rain barrels, green roofs, etc.) ☐ Proposed Harvest and Use BMPs ☒ Underlying hydrologic soil group (Web Soil Survey) ☒ Existing natural hydrologic features (watercourses, seeps, springs, wetlands, pond, lake) ☒ Existing topography and impervious areas ☒ Proposed grading and impervious areas. If the project is a subdivision or spans multiple lots show pervious and impervious totals for each lot. ☒ Existing and proposed site drainage network and connections to drainage offsite ☐ Potable water wells, onsite wastewater treatment systems (septic), underground utilities ☐ Structural BMPs (identify location, structural BMP ID No., type of BMP, and size/detail) ☐ Approximate depth to groundwater at each structural BMP ☐ Approximate infiltration rate and feasibility (full retention, partial retention, biofiltration) at each structural BMP ☐ Critical coarse sediment yield areas to be protected and or conveyed through the project site. ☐ Temporary Construction BMPs. Include protection of source control, site design and structural BMPs during construction. ☐ Onsite and Offsite Critical coarse sediment yield areas to be protected ☒ Proposed design features and surface treatments used to minimize imperviousness ☒ Existing and proposed drainage boundary and drainage area to each POC (when necessary, create separate exhibits for pre-development and post-project conditions) ☐ Structural BMPs for hydromodification management (identify location, type of BMP, and size/detail) 24 PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS Preparation Date: September 14, 2020 Template Date: September 26, 2019 Management of Critical Coarse Sediment Yield Areas (Attachment 2c) Document the findings of Site-specific Critical Coarse Sediment Analysis below. Include any calculations, and additional documentation completed as part of the analysis. Refer to Chapter 6.2 and Appendix H of the City of Temecula BMP Design Manual for additional guidance. The project effectively manages Critical Coarse Sediment Yield Areas (CCSYAs) using the following methodology: ☒ Step A. A Site-Specific Critical Coarse Sediment Yield Analysis was performed: ☐ Step A.1. Determine whether the project site is a significant source of critical coarse sediment to the channel receiving runoff (refer to CCSYA mapping in Appendix H): ☐ The project site is a significant source of Bed Sediment Supply. All channels on the project site are preserved or bypassed within the site plan. (Complete Step A.2, below) ☐ The project site is a source of Bed Sediment Supply. Channels identified as verified critical coarse sediment yield areas are preserved. (Complete Step A.2, below) ☒ The Project site is not a significant source of Bed Sediment Supply. (STOP, supporting information provided with this checklist) ☐ Impacts to verified CCSYAs cannot be avoided. (Complete Step B, below) ☐ Step A.2. Project site design avoids CCSYAs and maintains sediment supply pathways, documentation is provided following this checklist. (STOP, include supporting documentation with this checklist) ☐ Step B. Sediment Supply BMPs are implemented onsite to mitigate impacts of development in CCSYAs, documentation is provided following this checklist. (STOP, include supporting documentation with this checklist) PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS 25 Template Date: September 26, 2019 Preparation Date: September 14, 2020 Hydromodification Offsite Alternative Compliance Participation Form Refer to Chapter 1.8 Onsite Project Information Record ID: Assessor's Parcel Number(s) [APN(s)] Quantity of Hydromodification Debits or Credits (DCIA) ☐ Debits ☐ Credits *See Attachment 1 of the PDP WQMP Offsite Project Information – Projects providing or receiving credits (add rows as needed) Record ID: APN(s) Project Owner/Address Credit/Debit Quantity (DCIA) 1. ☐ Credit ☐ Debit 2. ☐ Credit ☐ Debit 3. ☐ Credit ☐ Debit 4. ☐ Credit ☐ Debit 5. ☐ Credit ☐ Debit 6. ☐ Credit ☐ Debit Total sum of Credits and Debits (∑Credits -∑Debits) (DCIA) Additional Information Are offsite projects in the same credit trading area as the onsite project? ☐ Yes ☐ No Do offsite projects discharge directly to the same susceptible stream reach as the onsite project? (required for certain hydromodification scenarios) ☐ Yes ☐ No Will projects providing credits be completed prior to completion of projects receiving credits? ☐ Yes ☐ No Are all deficits accounted for? If No, onsite and offsite projects must be redesigned to account for all deficits. ☐ Yes ☐ No Provide supporting WQE calculations as part of this attachment. S a n t a M arg arita River 0 1 2 Miles $ June 20, 2018 Pa t h : D : \ P r o j e c t \ S o C a l \ D e l i v e r a b l e \ M A P S \ S a n t a M a r g a r i t a W a t e r S h e d _ C r i t i c a l C o a r s e _ 1 1 x 1 7 _ S u b S h e d s _ S a n d G r a v e l D e p o s i t s _ p k g _ v 2 . m x d Santa Margarita River Watershed Boundary Protected Lands Potential Critical Coarse Sediment Yield Area Potential Sediment Source Area !!?Sand and Gravel Deposits Riverside Co. San Diego Co. Santa Margarita Eco Reserve SANTA MARGARITA RIVER WATERSHED POTENTIAL CRITICAL COARSE SEDIMENT YIELD AREAS AND POTENTIAL SEDIMENT SOURCE AREASExhibit G-1 APROX SITE LOCATION 26 PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS Preparation Date: September 14, 2020 Template Date: September 26, 2019 ATTACHMENT 3 Structural BMP Maintenance Information Indicate which Items are Included behind this cover sheet: Maintenance Responsibility has been assigned to: ☐ Property Owner ☐ Special District ☐ City of Temecula ☒ Attachment 3 is not required because the project does not propose structural BMPs ☐ Not applicable at this time – Discretionary Project Attachment Sequence Contents Checklist Attachment 3 Standard Structural BMP Water Quality Management Plan Operation and Maintenance Agreement (BMP Design Manual Appendix A.3) ☐ Included ☐ Signed, Notarized, and Recorded* ☐ City Maintained – Do Not Record, must be reviewed & accepted by City Maintenance Dept. Exhibit A Legal Description ☐ Included Exhibit B Individual Structural BMP DMA Mapbook (WQMP Exhibits) ☐ Included ☐ Place each map on 8.5”x11” paper ☐ BMP Site layout – Clearly depict location of each BMP ☐ Legible construction details of each BMP. Exhibit C Structural BMP Maintenance Plan (Required) ☐ Included See Structural BMP Maintenance Information Checklist on the back of this Attachment cover sheet. Exhibit D Structural BMP Design Fact Sheets (Appendix E) ☐ Included Note* Do not notarize & record until City staff has reviewed and approved the final Water Quality Management Plan Operation and Maintenance Agreement. PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS 27 Template Date: September 26, 2019 Preparation Date: September 14, 2020 Use this checklist to ensure the required information has been included in the Structural BMP Maintenance Plan Exhibit: Attachment 3 Exhibit C must identify: ☐ Purpose of the Operation and Maintenance Manual ☐ General description and function of all Structural BMPs implemented ☐ Inspection & Maintenance Documentation. Refer to Chapter 7.4 ☐ Inspection, Maintenance, & Reporting Frequency: Refer to Chapter 7.5 ☐ Measures to Control Maintenance Costs. Refer to Chapter 7.6 ☐ Maintenance indicators and actions for structural BMP(s). Refer to Chapter 7.7 ☐ Structural BMP Life Cycle Cost Analysis including Inspection, Maintenance, documentation, reporting, and replacement. 28 PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS Preparation Date: September 14, 2020 Template Date: September 26, 2019 ATTACHMENT 4 City of Temecula PDP Structural BMP Verification for Permitted Land Development Projects ☐ Not applicable at this time – Discretionary Project ☒ Attachment 4 is not required because the project does not propose structural BMPs PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS 29 Template Date: September 26, 2019 Preparation Date: September 14, 2020 This page was left intentionally blank. 30 PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS Preparation Date: September 14, 2020 Template Date: September 26, 2019 City of Temecula Structural BMP Verification Form Project Summary Information Project Name Record ID (e.g., grading/improvement plan number) Project Address Assessor's Parcel Number(s) (APN(s)) Project Watershed (Complete Hydrologic Unit, Area, and Subarea Name with Numeric Identifier) Responsible Party for Construction Phase Developer's Name Address Email Address Phone Number Engineer of Work Engineer's Phone Number Responsible Party for Ongoing Maintenance Owner's Name(s)* Address Email Address Phone Number *Note: If a corporation or LLC, provide information for principal partner or Agent for Service of Process. If an HOA, provide information for the Board or property manager at time of project closeout. PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS 31 Template Date: September 26, 2019 Preparation Date: September 14, 2020 City of Temecula Structural BMP Verification Form Page 2 of 4 Stormwater Structural Pollutant Control & Hydromodification Control BMPs* (List all from WQMP) Description/Type of Structural BMP Plan Sheet # STRUCT- URAL BMP ID# Maintenance Agreement Recorded Doc # Revisions Note: If this is a partial verification of Structural BMPs, provide a list and map denoting Structural BMPs that have already been submitted, those for this submission, and those anticipated in future submissions. 32 PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS Preparation Date: September 14, 2020 Template Date: September 26, 2019 City of Temecula Structural BMP Verification Form Page 3 of 4 Checklist for Applicant to submit to City inspector: ☐ Photograph of each completed Structural BMP. ☐ Photograph(s) of each Structural BMP during the construction process to illustrate proper construction as described in the Structural BMP Fact sheets. ☐ Certificates of compliance for materials as required in the Structural BMP Fact sheets. ☐ Infiltration Tests as required in the Structural BMP Fact sheets. By signing below, I certify that the Structural BMP(s) for this project have been constructed and all BMPs are in substantial conformance with the approved plans and applicable regulations. I understand the City reserves the right to inspect the above BMPs to verify compliance with the approved plans and City Ordinances. Should it be determined that the BMPs were not constructed to plan or code, corrective actions may be necessary before permits can be closed. Please sign your name and seal. Professional Engineer's Printed Name: Professional Engineer's Signed Name: Date: PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS 33 Template Date: September 26, 2019 Preparation Date: September 14, 2020 City of Temecula Structural BMP Verification Form Page 4 of 4 City - OFFICIAL USE ONLY: For City Inspector: Verification Package #: __________ City Inspector: Date Project has/expects to close: Date verification received from EOW: By signing below, City Inspector concurs that every noted Structural BMP has been installed per plan. City Inspector’s Signature: _______________________________ Date: For Land Development Staff: Date Received from City Inspector: Land Development Submittal Reviewer: Land Development Reviewer concurs that the information provided for the following Structural BMPs is acceptable to enter into the Structural BMP Maintenance verification inventory: List acceptable Structural BMPs: Land Development Reviewer’s Signature: Date: 34 PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS Preparation Date: September 14, 2020 Template Date: September 26, 2019 ATTACHMENT 5 Copy of Plan Sheets Showing Permanent Stormwater BMPs, Source Control, and Site Design Use this checklist to ensure the required information has been included on the plans: The plans must identify: ☐ Structural BMP(s) with ID numbers ☒ The grading and drainage design shown on the plans must be consistent with the delineation of DMAs shown on the DMA exhibit ☐ Improvements within City Public Right-of-Way have been designed in accordance with Appendix K: Guidance on Green Infrastructure. ☐ Details and specifications for construction of structural BMP(s). ☐ Manufacturer and part number for proprietary parts of structural BMP(s) when applicable. ☒ Signage indicating the location and boundary of source control, site design, and structural BMP(s) as required by City staff. ☐ How to access the structural BMP(s) to inspect and perform maintenance. ☐ Features that are provided to facilitate inspection (e.g., observation ports, cleanouts, silt posts, benchmarks or other features that allow the inspector to view necessary components of the structural BMP and compare to maintenance thresholds) ☐ Include landscaping plan sheets showing vegetation and amended soil requirements for vegetated structural BMP(s), amended soil areas, dispersion areas, tree-wells, and self- mitigating areas ☐ All BMPs must be fully dimensioned on the plans ☒ Include all Construction stormwater, source control, and site design measures described in the WQMP. Can be included as separate plan sheets as necessary. ☐ When proprietary BMPs are used, site-specific cross section with outflow, inflow, and model number must be provided. Photocopies of general brochures are not acceptable. PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS 35 Template Date: September 26, 2019 Preparation Date: September 14, 2020 This page was left intentionally blank. A B SHO W A L T E R R O A D SH O W A L T E R R O A D 945-070-004 945-070-003 945-080-025 945-070-020 945-070-009 945-070-015 945-070-009 945-070-001 945-070-004 C LD19-3729 EARTHEN BERM DETAIL 36 PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS Preparation Date: September 14, 2020 Template Date: September 26, 2019 ATTACHMENT 6 Copy of Project's Drainage Report Use this checklist to ensure the required information has been included on the Drainage Report: ☒ The project is required to prepare and submit a CEQA Drainage Study in compliance with Riverside County Flood Control and Water Conservation District Hydrology Manual: http://rcflood.org/downloads/Planning/Hydrology%20Manual%20-%20Complete.pdf In addition to the guideline, the study shall include the following but not limited to: ☒ The final CEQA Drainage report shall be signed, stamped and dated by the responsible Registered Civil Engineer. ☒ In the narrative of the report please provide a summary table of: pre- and post- development C, Tc, I, A, V100, Q100 without mitigation and Q100 with mitigation for each area (or point) where drainage discharges from the project. Peak runoff rates (cfs), velocities (fps) and identification of all erosive velocities (at all points of discharge) calculations for pre-development and post-development. The comparisons should be made about the same discharge points for each drainage basin affecting the site and adjacent properties. ☒ Summary/Conclusion: Please discuss whether the proposed project would substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of a stream or river, in a manner which would result in substantial erosion or siltation on- or off-site? Provide reasons and mitigations proposed. ☒ Discuss whether the proposed project would substantially alter the existing drainage pattern of the site or area, including through the alteration of the course of a stream or river, or substantially increase the rate or amount of surface runoff in a manner which would result in flooding on- or off-site? Provide reasons and mitigations proposed. ☒ Discuss whether the proposed project would create or contribute runoff water which would exceed the capacity of existing or planned stormwater drainage systems. Provide reasons and mitigations proposed. ☒ Discuss whether the proposed project would place housing within a 100-year flood hazard area as mapped on a federal Flood Hazard Boundary or Flood Insurance Rate Map or other flood hazard delineation map, including County Floodplain Maps. Provide reasons and mitigations proposed. ☒ Discuss whether the proposed project would place structures within a 100-year flood hazard area, which would impede or redirect flood flows. ☒ Discuss whether the proposed project would expose people or structures to a significant risk of loss, injury or death involving flooding as a result of the failure of a levee or dam. PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS 37 Template Date: September 26, 2019 Preparation Date: September 14, 2020 ☒ Provide existing and proposed Hydrology Maps for each phase. The maps shall show existing and proposed culverts, discharge point with A & Q, flow path direction for each drainage basin. Show existing FEMA floodplain/floodway which flow through the property. A minimum map size is 11"x17". ☒ Provide Hydrologic Soil Group Map. ☒ Provide Rainfall Isopluvials for 100 Year Rainfall Event - 6 Hours and 24 Hours Maps. ☒ The report should have numbered pages and a corresponding Table of Contents. ☐ Improvements within City Public Right-of-Way have been designed in accordance with Appendix K: Guidance on Green Infrastructure. BMP’s have been designed to safely convey the 100-year flood If hardcopy or CD is not attached, the following information should be provided: Title: Hydrology Report McGovern Residence LD19-3729 Prepared By: Ventura Engineering Inland, Inc. 27393 Ynez Road, Suite 159 Temecula, California 92591 Date: September 14, 2020 VENTURA ENGINEERING INLAND, INC. 27393 YNEZ ROAD, SUITE 159, TEMECULA, CALIFORNIA 92591 TOLL FREE OFFICE (877) 723-4224 FAX (951) 552-1686 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD TEMECULA, CALIFORNIA 92592 APN: 945-070-001 PARCEL 4 OF PARCEL MAP 17105 PER PM 97/11 PREPARED FOR: KEVIN MC GOVERN 40155 PASADENA DRIVE TEMECULA, CALIFORNIA 92591 (951) 837-0633 PREPARED BY: VENTURA ENGINEERING INLAND, INC 27393 YNEZ ROAD, SUITE 159 TEMECULA, CALIFORNIA 92591 (951) 252-7632 Revision 2: September 14, 2020 Revision 1: July 10, 2020 Original: October 25, 2019 (By Others, Not CEQA Analysis) I hereby declare that I am the engineer of work for this project, that I have exercised responsible charge over the design of the project as defined in Section 6703 of the Business and Professions code, and that the design is consistent with current standards. _____________________________ ______________ WILFREDO VENTURA DATE R.C.E. NO. 66532 EXPIRES 6/30/20 9/14/2020 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Rev2: 9/14/20, Rev1: 7/10/20 2019-092 McGovern Residence - i - Original: 10/25/19 TABLE OF CONTENTS DESCRIPTIONS PAGE COVER SHEET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . i TABLE OF CONTENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii 1.0 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2.0 LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 3.0 METHODOLOGY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 4.0 RUNOFF INDEX NUMBERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 5.0 EXISTING CONDITIONS CALCULATIONS . . . . . . . . . . . . . . . . . . . . 2 6.0 PROPOSED CONDITIONS CALCULATIONS . . . . . . . . . . . . . . . . . . 3 7.0 COMPARISON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 8.0 VELOCITY DISSIPATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 9.0 PAD INLET CAPACITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 10.0 CONCLUSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 11.0 REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 12.0 DECLARATION OF RESPONSIBLE CHARGE . . . . . . . . . . . . . . . . . 8 13.0 ATTACHMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 13.1 ATTACHMENT 1: STANDARDS EXCERPTS . . . . . . . . . . . . . 8 13.2 ATTACHMENT 2: EXISTING CONDITIONS CALCULATIONS 8 13.3 ATTACHMENT 3: PROPOSED CONDITIONS CALCULATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 13.4 ATTACHMENT 4: EXHIBITS . . . . . . . . . . . . . . . . . . . . . . . . . . 8 13.5 ATTACHMENT 5: FEMA ANALYSIS . . . . . . . . . . . . . . . . . . . . 8 ATTACHMENT 1: STANDARDS EXCERPTS ATTACHMENT 2: EXISTING CONDITIONS CALCULATIONS ATTACHMENT 3: PROPOSED CONDITIONS CALCULATIONS ATTACHMENT 4: EXHIBITS ATTACHMENT 5: FEMA ANALYSIS HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Rev2: 9/14/20, Rev1: 7/10/20 2019-092 McGovern Residence - 1 - Original: 10/25/19 1.0 INTRODUCTION The purpose of this report is to calculate the pre-development and post development hydrology conditions for the construction of the proposed single-family residence located on the currently vacant residential lot on Showalter Road in Temecula, California. The proposed project elements include pad grading, a single-family residence, multiple drainage swales, a private storm drain system, permeable areas, tree wells for stormwater mitigation and a private storm drain culvert under the proposed driveway that has been sized for the 100-Year Design Storm Event. This report has been created using the Riverside County Flood Control and Water Conservation District Hydrology Manual (April 1978). 2.0 LOCATION The project site is located at the southern side of Showalter Road, which is also south of Pauba Road in Temecula, California 92592. A vicinity map is provided for reference in Attachment 4. 3.0 METHODOLOGY This report calculates 100-Year Maximum Peak Runoff based on the Riverside County Flood Control and Water Conservation District Hydrology Manual (April 1978) rational methodology. In addition, this manual will be referred to as the ‘Standards’ throughout this report. Clean copies of the excerpts from the standards and a selection of other design references have been included in Attachment 1: Standards Excerpts for reference. The hydrology calculations will be divided into existing conditions and proposed conditions. The existing conditions calculations are provided in Attachment 2: Existing Conditions Calculations. The proposed calculations are provided for reference in Attachment 3: Proposed Conditions. Hydrology maps have also been created for the project site and are included in Attachment 4: Exhibits. In addition, FEMA analysis is provided for reference in Attachment 5: FEMA Analysis. 4.0 RUNOFF INDEX NUMBERS In support of more accurate calculations, the existing and proposed conditions have calculated individual basin imperviousness values, overall cover types, and quality of covers to generalize the average runoff coefficient data that is then interpolated in the software for the hydrology calculations. for the runoff coefficients and the associated land use for the soil type and quality of cover for C soils have been used for the sub-basins in the calculations. A summary is as follows: EXISTING CONDITIONS RUNOFF COEFFICIENTS DRAINAGE SUB-AREA QUALITY OF COVER SOIL GROUP C GENERAL (ADJUSTED TO AMCII) ALL POOR, UNMAINTAINED UNDISTURBED NATURAL HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Rev2: 9/14/20, Rev1: 7/10/20 2019-092 McGovern Residence - 2 - Original: 10/25/19 PROPOSED CONDITIONS RUNOFF COEFFICIENTS DRAINAGE SUB-AREA QUALITY OF COVER SOIL GROUP C GENERAL (ADJUSTED TO AMCII) 1.1 – 1.3; 1.6; 1.8 1.10 – 1.11 2.1 – 2.2 3.2 POOR, UNMAINTAINED UNDISTURBED NATURAL 1.4 – 1.5; 1.7; 1.9 3.1 URBAN – SINGLE FAMILY RESIDENTIAL SINGLE-FAMILY RESIDENTIAL 1 DU / ACRE 5.0 EXISTING CONDITIONS CALCULATIONS The existing conditions have been evaluated using the Rational Method from the Riverside County Flood Control and Water Conservation District Hydrology Manual (April 1978). Certain tables and figures from the Standards are referenced in this report and have been included in Attachment 1: Standards Excerpts. The existing conditions calculations are in Attachment 2 for reference. The existing conditions exhibit is provided for reference in Attachment 4. A summary of the existing conditions calculations is as follows at the three general locations where it is hydrologically feasible to analyze flows exiting the property lines: CONFLUENCE POINT A EXISTING CONDITIONS SUMMARY DATA 100-YEAR TIME OF CONCENTRATION (MIN) 6.49 INTENSITY (IN/HR) 4.861 AREA (ACRES) 4.549 TOTAL DISCHARGE (CFS) 17.5 VELOCITY (FPS) 6.1 CONFLUENCE POINT B EXISTING CONDITIONS SUMMARY DATA 100-YEAR TIME OF CONCENTRATION (MIN) 5.37 INTENSITY (IN/HR) 4.901 AREA (ACRES) 0.507 TOTAL DISCHARGE (CFS) 2.2 VELOCITY (FPS) 7.4 CONFLUENCE POINT C EXISTING CONDITIONS SUMMARY DATA 100-YEAR TIME OF CONCENTRATION (MIN) 5.37 INTENSITY (IN/HR) 4.902 AREA (ACRES) 0.318 TOTAL DISCHARGE (CFS) 1.4 VELOCITY (FPS) 7.4 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Rev2: 9/14/20, Rev1: 7/10/20 2019-092 McGovern Residence - 3 - Original: 10/25/19 6.0 PROPOSED CONDITIONS CALCULATIONS The proposed conditions have been evaluated using the Rational Method from the Riverside County Flood Control and Water Conservation District Hydrology Manual (April 1978). Certain tables and figures from the Standards are referenced in this report and have been included in Attachment 1: Standards Excerpts. The proposed conditions calculations are located in Attachment 3 for reference. The proposed conditions exhibit is provided for reference in Attachment 4. A summary of the proposed conditions calculations is as follows at the three general locations where it is hydrologically feasible to analyze flows exiting the property lines: CONFLUENCE POINT A PROPOSED CONDITIONS SUMMARY DATA 100-YEAR TIME OF CONCENTRATION (MIN) 7.45 INTENSITY (IN/HR) 4.095 AREA (ACRES) 4.846 TOTAL DISCHARGE (CFS) 17.1 VELOCITY (FPS) 4.8 CONFLUENCE POINT B PROPOSED CONDITIONS SUMMARY DATA 100-YEAR TIME OF CONCENTRATION (MIN) 5.14 INTENSITY (IN/HR) 5.021 AREA (ACRES) 0.288 TOTAL DISCHARGE (CFS) 1.3 VELOCITY (FPS) 6.2 CONFLUENCE POINT C PROPOSED CONDITIONS SUMMARY DATA 100-YEAR TIME OF CONCENTRATION (MIN) 9.44 INTENSITY (IN/HR) 3.595 AREA (ACRES) 0.497 TOTAL DISCHARGE (CFS) 1.6 VELOCITY (FPS) 8.1 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Rev2: 9/14/20, Rev1: 7/10/20 2019-092 McGovern Residence - 4 - Original: 10/25/19 7.0 COMPARISON The project site proposes the use of slope flattening, self-mitigating areas, and tree wells to meet low impact development processes; but also, the site’s proposed design also meets hydromodification management elements as well. This will be accomplished by draining impervious areas to adjacent permeable areas and amended soil landscape areas per the standards and discharging all pad locations through tree well areas. Comparison data summaries at Compliance Point A and B is as follows: COMPLIANCE POINT A COMPARISON DATA EXISTING CONDITIONS 100-YEAR PROPOSED CONDITION 100-YEAR COMPARISON TIME OF CONCENTRATION (MIN) 6.49 7.45 + 0.96 INTENSITY (IN/HR) 4.861 4.095 - 0.766 AREA (ACRES) 4.549 4.846 + 0.297 TOTAL DISCHARGE (CFS) 17.5 17.1 - 0.4 VELOCITY (FPS) 6.1 4.8 - 1.3 COMPLIANCE POINT B COMPARISON DATA EXISTING CONDITIONS 100-YEAR PROPOSED CONDITION 100-YEAR COMPARISON TIME OF CONCENTRATION (MIN) 5.37 5.14 - 0.23 INTENSITY (IN/HR) 4.901 5.021 + 0.120 AREA (ACRES) 0.507 0.288 - 0.219 TOTAL DISCHARGE (CFS) 2.2 1.3 - 0.9 VELOCITY (FPS) 7.4 6.2 - 1.2 COMPLIANCE POINT C COMPARISON DATA EXISTING CONDITIONS 100-YEAR PROPOSED CONDITION 100-YEAR COMPARISON TIME OF CONCENTRATION (MIN) 5.37 9.44 + 4.07 INTENSITY (IN/HR) 4.902 3.595 + 1.307 AREA (ACRES) 0.318 0.497 + 0.179 TOTAL DISCHARGE (CFS) 1.4 1.6 + 0.2 VELOCITY (FPS) 7.4 8.1 + 0.7 Comparison Point B and C Note: It should be noted that although there is an increase at Comparison Point C of 0.2 cfs in the 100-Tear Design Storm Event, there is also a decrease at Comparison Point B of 0.9 cfs. These two Comparison Points are taken at the physical property line; however, they will confluence approximately 30 feet downstream of each other in another gully so the overall net decrease will be 0.7 cfs in the 100-Year Design Storm Event to the downstream property owner as there are no improvements between the property line at this downstream confluence. HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Rev2: 9/14/20, Rev1: 7/10/20 2019-092 McGovern Residence - 5 - Original: 10/25/19 8.0 VELOCITY DISSIPATION There project proposes some elements of velocity dissipation through the use of rip rap energy dissipation devices. The rip rap dissipators are designed per the node run analysis and a standard detail is provided in Attachment 1 for reference. Please refer to the detail for further design information based on the summary below. The 100-Year Design Storm Event calculations are provided in Attachment 3 by node analysis and is summarized as follows: RIP RAP ENERGY DISSIPATION ELEMENTS – 100-YEAR DESIGN STORM EVENT NODE RUNS VELOCITY (FPS) ROCK CLASSIFICATION DISSIPATOR CONFIGURATION T (FT) ** SILL TYPE *** INTO OUT OF BASE WIDTH (FT) * MAX. DEPTH (FT) SIDE SLOPES 1.32 1.33 7.2 3.7 1/4 TON ROCK 2.5 1.0 3:1 2.7 1 1.33 - 1.54 1.61 13.9 2.8 1/4 TON ROCK 2.5 1.0 3:1 2.7 1 1.53 - 1.54 9.8 1.61 - 1.103 1.111 14.6 4.6 1/4 TON ROCK 2.5 1.0 3:1 2.7 1 1.102 - 1.103 18.0 3.15 3.21 3.8 3.7 #2 BACKING ROCK 2.5 1.0 3:1 1.1 1 NOTES: * RIP RAP DISSIPATORS ARE ALL 5’ WIDE. CHANNELS ARE ASSUMED TO BE TRAPEZOIDAL AND THE BASE WIDTH OF THE CHANNEL IS LISTED. ** ‘T’ IS ROCK THICKNESS PER THE DETAIL. *** SILL TYPE 1 IS CONCRETE AND SILL TYPE 2 IS NO SILL NEEDED PER THE DETAIL. HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Rev2: 9/14/20, Rev1: 7/10/20 2019-092 McGovern Residence - 6 - Original: 10/25/19 9.0 PAD INLET CAPACITY The project proposes grated inlets on the pad near the proposed single-family residence. These grates have been designed to pass the 100-Year Design Storm Event without ponding. The sub-areas of the proposed conditions that are utilizing grated inlets are listed in the summary table below. A specification sheet from the proposed grate inlet manufacturer is provided in Attachment 1 and the proposed hydrology calculations node analysis is provided in Attachment 3 for reference. A summary of the inlet capacities are as follows: PAD INLET CAPACITIES 100-YEAR DESIGN STORM EVENT PROPOSED CONDITIONS NODE PROPOSED CONDITIONS Q100 (CFS) CAPACITY NEEDED PROPOSED QTY AND GRATE INLET TYPE INLET CAPACITY (CFS) (EACH) * TOTAL PROPOSED INLET CAPACITY (CFS) 1.53 2.0 (1) 24x24 NDS 2415 (O.A.E.) 2.88 EACH 2.88 1.73 1.3 (1) 18x18 NDS 1815 (O.A.E.) 1.63 EACH 1.63 1.92 0.4 (1) 12x12 NDS 1215 (O.A.E.) 0.91 EACH 0.91 3.14 1.3 (1) 18x18 NDS 1815 (O.A.E.) 1.63 EACH 1.63 NOTES: * PER THE MANUFACTURER’S DETAILS, THE NDS GRATE CAPACITIES ARE PROVIDED FOR REFERENCE IN ATTACHMENT 1 AND HAVE BEEN SELECTED TO PASS THE 100- YEAR DESIGN STORM EVENT ENTIRELY. 10.0 CONCLUSION The proposed project site will construct new structures and various other design elements that will add to the improvements of an existing vacant residential lot that is zoned and will remained zoned for single- family residential use. The proposed development will utilize low impact development solutions to handle water quality treatment and hydromodification. The project site increases the imperviousness of the site, but the proposed LID elements, permeable paving areas, self-mitigating areas and tree wells are more than adequate to mitigate this increase using the include design elements as outlined in the Site-Specific WQMP (separate document). With this in mind, the project proposes to decrease the peak discharge rates at the property line and adjacent confluence points as presented in the comparison summaries and notes in Section 7.0. In addition, the following statements also apply to the project site as proposed: Existing Drainage Pattern Impact Statement: The project site does not substantially are the existing drainage patterns of the project site or localized streams that would result in substantial erosion or siltation on- or -off site. Surface Runoff Statement: The project site does not substantially are the existing drainage patterns of the project site or localized streams that would result in substantial surface water increase on- or -off site. HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Rev2: 9/14/20, Rev1: 7/10/20 2019-092 McGovern Residence - 7 - Original: 10/25/19 Planned Stormwater Improvements Impact Statement: The project site does not substantially are the existing drainage patterns of the project site or localized streams that would result in substantial changes to any future storm drain improvements planned for the area. At this time, the City has not made the applicant or engineer of record aware of any such planned future storm drain improvements. House in a 100-Year Flood Hazard Area Impact Statement: Although the project site proposes residential housing, FEMA analysis provided in Attachment 5 illustrate that the project site will not posse a flooding risk or impact at this time. Structures in a 100-Year Flood Hazard Area Impact Statement: FEMA analysis provided in Attachment 5 illustrate that the project site is not proposing any structures in the 100-Year Flood Hazard Area as defined by FEMA Mapping. Flood Impact Statement: It is the opinion of the engineer of record for this project that, as proposed, the project improvements will not expose people or structures toa significant risk of loss, injury, or death involving flooding as a result of the failure of the proposed improvements, let alone a levee or dam. 11.0 REFERENCES The following references were utilized in the creation of this hydrology report: Brater & King, Handbook of Hydraulics, 6th ed. Design Handbook for Low Impact Development Best Management Practices, Riverside County Flood Control & Water Conservation District, September 2011. Hydrology Manual, Riverside County Flood Control & Water Conservation District, April 1978 San Diego Area Regional Standard Drawings, Standard Drawings for Agencies in the San Diego Region, Maintained and Published by the County of San Diego, Department of Public Works April 2006 San Diego County Drainage Design Manual, Prepared for the County of San Diego, Department of Public Works, Flood Control Section September 2014. HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Rev2: 9/14/20, Rev1: 7/10/20 2019-092 McGovern Residence - 8 - Original: 10/25/19 12.0 DECLARATION OF RESPONSIBLE CHARGE I hereby declare that I am the engineer of work for this project, that I have exercised responsible charge over the design of the project as defined in Section 6703 of the Business and Professions code, and that the design is consistent with current standards. I understand that the check of project drawings and specifications by the agency is confined to a review only and does not relieve me, as engineer of work, of my responsibilities for project design. __________________________ ________________ Wilfredo Ventura Date 13.0 ATTACHMENTS The following attachment sections are provided for reference: 13.1 ATTACHMENT 1: STANDARD EXCERPTS This attachment contains excerpts from the standards and other design reference materials. Please refer to the attached references. 13.2 ATTACHMENT 2: EXISTING CONDITIONS CALCULATIONS This attachment contains the existing conditions calculations. The existing conditions calculations are summarized in Section 4 of the report. Calculations are provided here for reference. 13.3 ATTACHMENT 3: PROPOSED CONDITIONS CALCULATIONS This attachment contains the proposed conditions calculations. The proposed conditions calculations are summarized in Section 5 of the report. Calculations are provided here for reference. 13.4 ATTACHMENT 4: EXHIBITS The Existing Conditions Hydrology Exhibit, Proposed Conditions Hydrology Exhibit, and a detail sheet are provided here for reference. 13.5 ATTACHMENT 5: FEMA ANALYSIS The site-specific FEMA Analysis is provided here for reference. 9/14/20 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 ATTACHMENT 1: STANDARD EXCERPTS This attachment contains various excerpts from the Riverside County Flood Control & Water Conservation District Hydrology Manual (April 1978 edition). Please see the attached excerpts from the standards. 0.049 0.047 0.045 0.044 0.037 n Chapter 5. Open Channels San Diego County Hydraulic Design Manual Page 5-17 September 2014 where ... n = Manning roughness coefficient (dimensionless); and d50 = median stone diameter (feet). Table 5-4 Standard Rock Riprap Gradations ##Rock Gradation a Median Stone Weight (W50) c Median Stone Diameter (d50) d Manning n (Ungrouted) e No. 3 Backing 5 lb 0.4 ft 0.034 No. 2 Backing 25 lb 0.7 ft 0.037 No. 1 Backing b 75 lb 1.0 ft 0.039 Light 200 lb 1.3 ft 0.041 ¼ Ton 500 lb 1.8 ft 0.044 ½ Ton 1000 lb 2.3 ft 0.045 1 Ton 2000 lb 2.9 ft 0.047 2 Ton 4000 lb 3.6 ft 0.049 (a) Except for 2 ton rock, classification is based upon Caltrans Method B Placement, which allows dumping of the rock and spreading by mechanical equipment. Local surface irregularities shall not vary from the planned grade by more than 1 foot, measured perpendicular to the slope. Two-ton rock requires special placement, see Caltrans (2002) or Greenbook for more information. (b) No. 1 Backing has same gradation as Facing Riprap. (c) per Caltrans (2002). (d) Assumes specific weight of 165 lb/ft3. The designer shall take care to apply a unit weight that is applicable to the type of riprap specified for the project, and adjust their calculations when necessary. (e) Based on Manning-Strickler relationship (Chang, 1988). Where hydraulic radius is less than or equal to two times the maximum rock size, the roughness coefficient will be greater than indicated by Equation 5-5. In these cases, the design engineer shall use the method outlined in Section 5.7.17 to calculate the roughness of the channel. Appendix A (Table A-3) provides recommended Manning roughness coefficient (n) for grouted riprap applications. A 20% roughness coefficient reduction ( N grouted = 0.80 N ungrouted) for grouted rip-rap shall be required for velocity-based design for energy dissipation/scour minimization measures applications. For channel capacity design, the roughness coefficients in Table 5-4 and Appendix A shall be used. 5.7.3 Low Flow and Trickle Channels Riprap-lined channels conveying a 100-year peak runoff of 20 cfs or less do not require trickle channels. The design engineer shall evaluate the factors such as drainage slope, flow velocity, soil type, and upstream impervious area, and specify a trickle channel when needed based on their engineering judgment. Low-flow channels shall be designed in accordance with Section 5.5.3.2. 5.7.4 Bottom Width The selection of the over-all channel bottom width shall consider factors such as ultimate conveyance requirements, constructability, channel stability, and maintenance. 5.7.5 Freeboard and Flow Depth Riprap-lined channels shall meet the minimum freeboard requirements outlined in Section 5.3.7. Excessive depths and high velocities shall be avoided whenever practicable to maintain public safety. Section 5.3.9 discusses access and safety for open channels, including thresholds for flow depth and velocity. 5.7.6 Side Slopes The side slopes of riprap-lined channel shall not ordinarily be steeper than 2H:1V, except in cases where an embankment stability analysis can justify a steeper side slope. The stability analysis should be completed in consultation with a soils engineer, and consider such factors such as: soil DR A I N A G E 11 5⁄8" 3⁄4" Grate Openings 1 1⁄8" 11 5⁄8" 3⁄8" Grate Openings 1" 2 Open Slides 3⁄4" 1⁄4" 11 7⁄8" 12" Catch Basin Series (continued) Part No. Description Color Pkg. Qty. Wt. Ea. (lbs.) Product Class Specifi cations 1213 12" x 12" Square Ductile Grate Black 1 15.30 10ND 12" Square Heavy-Duty Ductile Grate. Open surface area 37.20 square inches. 113.80 GPM. Use with 12" x 12" Catch Basin Series. (see page 72). ADA Compliant. Part No. Description Color Pkg. Qty. Wt. Ea. (lbs.) Product Class Specifi cations 1215 12" x 12" Square Galvanized Steel Grate Galvanized Steel 1 5.85 10ND 12" Square Heavy-Duty Galvanized Steel Bar Grate. Open surface area 113.78 square inches. 348.07 GPM. Use with 12" x 12" Catch Basin Series. (see page 72) Part No. Description Color Pkg. Qty. Wt. Ea. (lbs.) Product Class Specifi cations 1220 12" x 12" Sump Pump Box Black 8 2.23 10ND NDS #1220, 12" Square Structural Foam Polyolefi n Solid Cover.Use with NDS 12" x 12" Catch Basin Series and NDS #1219 Backwater Valve Box. Part No. Description Color Pkg. Qty. Wt. Ea. (lbs.) Product Class Specifi cations 1221 12" x 12" Square, Low-Profi le Adapter Black 12 1.92 10ND 12" x 12" Low-Profi le Adapter. Styrene.1222 12" x 12" Square, Low-Profi le Spigot Adapter Black 12 1.92 10ND Fits 8" Corrugated Pipe 5 15⁄16" 12 1⁄4" 4 1⁄8" 8 5⁄8" 1 1⁄8" Part No. Description Color Pkg. Qty. Wt. Ea. (lbs.) Product Class Specifi cations 1224CI 12" x 12" Square Wave Cast Iron Grate Raw Iron 1 13.90 10ND 12" Square Cast Iron Wave Grate. Open surface area 25.60 square inches. 78.31 GPM. Class B load rated.(see page 72). ADA Compliant. 11 3⁄4" 3⁄8" Grate Openings 1 1⁄8" Part No. Description Color Pkg. Qty. Wt. Ea. (lbs.) Product Class Specifi cations 1230 12" x 12" Low-Profi le Adapter Black 8 1.25 10ND 12" x 12" Low-Profi le Adapter. Styrene. Requires either #1243, #1245, #1266 or #1889 Universal Outlet for connection to 3", 4" or 6" Sewer and Drain or Corrugated Pipe. (see page 33)3 7⁄16" 12 1⁄4" 1 1⁄8" CATCH BASINS 29for videos, specs, detail drawings and case studies, visit ndspro.com LISTED CAPACITY IS 348.07 GPM=0.91 CFS DR A I N A G E NDS#1215 AI.eps 1" 16 3⁄4"1" Grate Openings NDS#1840 AI.eps 17 7⁄8" 1 1⁄4" NDS#1830 AI.eps 17 7⁄8" 3 5⁄8" 1 1⁄8" NDS#1820 AI.eps 19 1⁄4" 18 1⁄8" NDS#1828 AI.eps 1 1⁄8" 15 1⁄2" NDS#1822 AI.eps 19 1⁄4" 18 1⁄8" 6 1⁄4" 6 1⁄4"9 1⁄2" 1" NDS#1821 AI.eps 19 1⁄4" 18 1⁄8" 6 1⁄4" 6 1⁄4"9 1⁄2" 1" Part No.Description Color Pkg. Qty. Wt. Ea. (lbs.) Product Class Specifications 1820 Basin Side – No Opening Black 4 4.00 10ND 18" x 18" Catch Basin Side, No Opening. Styrene. Part No.Description Color Pkg. Qty. Wt. Ea. (lbs.) Product Class Specifications 1821 Basin Side – 8" Opening Black 4 4.00 10ND 18" x 18" Catch Basin Side, 8" Opening. Styrene.Reducer Ring not included. Requires #1888 Universal Outlet to fit 8" Corrugated Pipe or Sewer and Drain Pipe or #1266 Universal Outlets. #1889 Universal Outlet does not fit this #1821 Basin Side. Part No.Description Color Pkg. Qty. Wt. Ea. (lbs.) Product Class Specifications 1822 Basin Side – 6" or 8" Opening Black 4 3.75 10ND 18" x 18" Catch Basin Side, 6" or 8" Opening. Styrene.Opening using Universal Outlet. Includes #1890 Reducer Ring. Use with #1206, #1242, #1243, #1245, #1266 or #1888 Universal Outlets. Part No.Description Color Pkg. Qty. Wt. Ea. (lbs.) Product Class Specifications 1828 Basin Bottom Black 4 2.50 10ND 18" x 18" Catch Basin Bottom. Styrene. Part No.Description Color Pkg. Qty. Wt. Ea. (lbs.) Product Class Specifications 1815 18" Square Galvanized Steel Grate Galvanized Steel 1 10.78 10ND 18" Square Heavy-Duty Galvanized Steel Bar Grate. Open surface area 239.00 square inches. 731.13 GPM. Use with 18" x 18" Catch Basin Series. (see page 75) Part No.Description Color Pkg. Qty. Wt. Ea. (lbs.) Product Class Specifications 1840 Frame to adapt 18" x 18" grate to concrete catch basin Black 4 2.00 10ND 18" x 18" Frame. Styrene. Use with 18" x 18" Grates. Part No.Description Color Pkg. Qty. Wt. Ea. (lbs.) Product Class Specifications 1830 18" x 18" Low-Profile Adapter Black 4 4.75 10ND 18" x 18" Low-Profile Adapter. Styrene.Includes NDS #1890 Reducer Ring. Requires either an NDS #1243, #1245, #1266 or #1888 Universal Outlet to connect to pipe. 18" Catch Basin Series (continued) 18" Component Parts CATCH BASINS 20for videos, specs, detail drawings and case studies, visit ndspro.com LISTED CAPACITY IS 731.13 GPM=1.63 CFS DR A I N A G E 24" 1 5⁄8" 2" 4 3⁄8"14 1⁄2" NDS#2400 24 3⁄4" NDS#2418 24 3⁄4" 12 1⁄4" 2" NDS#24 0 8 3" NDS#2412.AI.eps 23 3⁄4" 2" 7⁄8" Grate Openings 1" Grate Openings 2" 23 7⁄8" 23 3⁄4" 2" 1 1⁄4" Grate OpeningsNDS#1215 AI.eps Part No.Description Color Pkg. Qty. Wt. Ea. (lbs.) Product Class Specifications 2410 10" & 12" Universal Adapter Black 1 4.20 10ND 10"/12" Universal Adapter. HDPE.Includes #1890 (comes pre-inserted). Fits 10" and 12" Sewer and Drain Pipe; 10" and 12" Dual Wall Corrugated Pipe; 12" Single Wall Corrugated Pipe (does not fit 10" Single Wall Corrugated Pipe). Reduces opening to fit most 3" to 8" adapters above (all except #1889) for use with 3", 4", 6" and 8" Sewer and Drain Pipe; 3", 4", 6" and 8" Corrugated Pipe; and 4" Sch. 40 Pipe (select corresponding adapter above). Use with 24" Catch Basin Series. Part No.Description Color Pkg. Qty. Wt. Ea. (lbs.) Product Class Specifications 2400 24" x 24" Catch Basin, 2 Openings Black 1 18.00 10ND 24" x 24" One-Piece Tapered Catch Basin. HDPE with Structural Foam.2404 24" x 24" Catch Basin, 4 Openings Black 1 15.00 10ND Requires 2 or 4 #2410 Universal Outlets. Part No.Description Color Pkg. Qty. Wt. Ea. (lbs.) Product Class Specifications 2418 24" x 24" Catch Basin Extension (No Bottom) Black 1 14.60 10ND 8" Extension for 24" x 24" Catch Basin. HDPE with Structural Foam.Use with 24" x 24" Catch Basin Series. 24" Catch Basin Series Part No.Description Color Pkg. Qty. Wt. Ea. (lbs.) Product Class Specifications 2411 24" x 24" Square Grate Black 1 19.75 10ND 24" Square HDPE with Structural Foam Grate with UV inhibitor. Open surface area 231.69 square inches. 708.77 GPM. 2412 24" x 24" Square Grate Green 1 19.75 10ND Use with 24" x 24" Catch Basin Series. (see page 75) Part No.Description Color Pkg. Qty. Wt. Ea. (lbs.) Product Class Specifications 2413 24" x 24" Square Cast Iron Grate Black 1 147.00 10ND 24" Square Heavy-Duty Cast Iron Grate. Open surface area 197.00 square inches. 602.65 GPM. Structural Foam. Use with 24" x 24" Catch Basin Series. (see page 75) Part No.Description Color Pkg. Qty. Wt. Ea. (lbs.) Product Class Specifications 2415 24" x 24" Square Galvanized Steel Grate Galvanized Steel 1 62.88 10ND 24" Square Heavy-Duty Galvanized Steel Bar Grate. Open surface area 422.45 square inches. 1292.33 GPM. Structural Foam. Use with 24" x 24" Catch Basin Series. (see page 75) CATCH BASINS 21 Product Catalog 2018 LISTED CAPACITY IS 1292.33 GPM=2.88 CFS United States Department of Agriculture A product of the National Cooperative Soil Survey, a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local participants Custom Soil Resource Report for Western Riverside Area, California McGovern Residence Natural Resources Conservation Service March 12, 2020 Preface Soil surveys contain information that affects land use planning in survey areas. They highlight soil limitations that affect various land uses and provide information about the properties of the soils in the survey areas. Soil surveys are designed for many different users, including farmers, ranchers, foresters, agronomists, urban planners, community officials, engineers, developers, builders, and home buyers. Also, conservationists, teachers, students, and specialists in recreation, waste disposal, and pollution control can use the surveys to help them understand, protect, or enhance the environment. Various land use regulations of Federal, State, and local governments may impose special restrictions on land use or land treatment. Soil surveys identify soil properties that are used in making various land use or land treatment decisions. The information is intended to help the land users identify and reduce the effects of soil limitations on various land uses. The landowner or user is responsible for identifying and complying with existing laws and regulations. Although soil survey information can be used for general farm, local, and wider area planning, onsite investigation is needed to supplement this information in some cases. Examples include soil quality assessments (http://www.nrcs.usda.gov/wps/ portal/nrcs/main/soils/health/) and certain conservation and engineering applications. For more detailed information, contact your local USDA Service Center (https://offices.sc.egov.usda.gov/locator/app?agency=nrcs) or your NRCS State Soil Scientist (http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/contactus/? cid=nrcs142p2_053951). Great differences in soil properties can occur within short distances. Some soils are seasonally wet or subject to flooding. Some are too unstable to be used as a foundation for buildings or roads. Clayey or wet soils are poorly suited to use as septic tank absorption fields. A high water table makes a soil poorly suited to basements or underground installations. The National Cooperative Soil Survey is a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local agencies. The Natural Resources Conservation Service (NRCS) has leadership for the Federal part of the National Cooperative Soil Survey. Information about soils is updated periodically. Updated information is available through the NRCS Web Soil Survey, the site for official soil survey information. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or a part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require 2 alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer. 3 Contents Preface....................................................................................................................2 How Soil Surveys Are Made..................................................................................5 Soil Map..................................................................................................................8 Soil Map................................................................................................................9 Legend................................................................................................................10 Map Unit Legend................................................................................................11 Map Unit Descriptions.........................................................................................11 Western Riverside Area, California.................................................................13 GzG—Gullied land......................................................................................13 RmE3—Ramona and Buren sandy loams, 15 to 25 percent slopes, severely eroded....................................................................................13 References............................................................................................................16 4 How Soil Surveys Are Made Soil surveys are made to provide information about the soils and miscellaneous areas in a specific area. They include a description of the soils and miscellaneous areas and their location on the landscape and tables that show soil properties and limitations affecting various uses. Soil scientists observed the steepness, length, and shape of the slopes; the general pattern of drainage; the kinds of crops and native plants; and the kinds of bedrock. They observed and described many soil profiles. A soil profile is the sequence of natural layers, or horizons, in a soil. The profile extends from the surface down into the unconsolidated material in which the soil formed or from the surface down to bedrock. The unconsolidated material is devoid of roots and other living organisms and has not been changed by other biological activity. Currently, soils are mapped according to the boundaries of major land resource areas (MLRAs). MLRAs are geographically associated land resource units that share common characteristics related to physiography, geology, climate, water resources, soils, biological resources, and land uses (USDA, 2006). Soil survey areas typically consist of parts of one or more MLRA. The soils and miscellaneous areas in a survey area occur in an orderly pattern that is related to the geology, landforms, relief, climate, and natural vegetation of the area. Each kind of soil and miscellaneous area is associated with a particular kind of landform or with a segment of the landform. By observing the soils and miscellaneous areas in the survey area and relating their position to specific segments of the landform, a soil scientist develops a concept, or model, of how they were formed. Thus, during mapping, this model enables the soil scientist to predict with a considerable degree of accuracy the kind of soil or miscellaneous area at a specific location on the landscape. Commonly, individual soils on the landscape merge into one another as their characteristics gradually change. To construct an accurate soil map, however, soil scientists must determine the boundaries between the soils. They can observe only a limited number of soil profiles. Nevertheless, these observations, supplemented by an understanding of the soil-vegetation-landscape relationship, are sufficient to verify predictions of the kinds of soil in an area and to determine the boundaries. Soil scientists recorded the characteristics of the soil profiles that they studied. They noted soil color, texture, size and shape of soil aggregates, kind and amount of rock fragments, distribution of plant roots, reaction, and other features that enable them to identify soils. After describing the soils in the survey area and determining their properties, the soil scientists assigned the soils to taxonomic classes (units). Taxonomic classes are concepts. Each taxonomic class has a set of soil characteristics with precisely defined limits. The classes are used as a basis for comparison to classify soils systematically. Soil taxonomy, the system of taxonomic classification used in the United States, is based mainly on the kind and character of soil properties and the arrangement of horizons within the profile. After the soil 5 scientists classified and named the soils in the survey area, they compared the individual soils with similar soils in the same taxonomic class in other areas so that they could confirm data and assemble additional data based on experience and research. The objective of soil mapping is not to delineate pure map unit components; the objective is to separate the landscape into landforms or landform segments that have similar use and management requirements. Each map unit is defined by a unique combination of soil components and/or miscellaneous areas in predictable proportions. Some components may be highly contrasting to the other components of the map unit. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The delineation of such landforms and landform segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, onsite investigation is needed to define and locate the soils and miscellaneous areas. Soil scientists make many field observations in the process of producing a soil map. The frequency of observation is dependent upon several factors, including scale of mapping, intensity of mapping, design of map units, complexity of the landscape, and experience of the soil scientist. Observations are made to test and refine the soil-landscape model and predictions and to verify the classification of the soils at specific locations. Once the soil-landscape model is refined, a significantly smaller number of measurements of individual soil properties are made and recorded. These measurements may include field measurements, such as those for color, depth to bedrock, and texture, and laboratory measurements, such as those for content of sand, silt, clay, salt, and other components. Properties of each soil typically vary from one point to another across the landscape. Observations for map unit components are aggregated to develop ranges of characteristics for the components. The aggregated values are presented. Direct measurements do not exist for every property presented for every map unit component. Values for some properties are estimated from combinations of other properties. While a soil survey is in progress, samples of some of the soils in the area generally are collected for laboratory analyses and for engineering tests. Soil scientists interpret the data from these analyses and tests as well as the field-observed characteristics and the soil properties to determine the expected behavior of the soils under different uses. Interpretations for all of the soils are field tested through observation of the soils in different uses and under different levels of management. Some interpretations are modified to fit local conditions, and some new interpretations are developed to meet local needs. Data are assembled from other sources, such as research information, production records, and field experience of specialists. For example, data on crop yields under defined levels of management are assembled from farm records and from field or plot experiments on the same kinds of soil. Predictions about soil behavior are based not only on soil properties but also on such variables as climate and biological activity. Soil conditions are predictable over long periods of time, but they are not predictable from year to year. For example, soil scientists can predict with a fairly high degree of accuracy that a given soil will have a high water table within certain depths in most years, but they cannot predict that a high water table will always be at a specific level in the soil on a specific date. After soil scientists located and identified the significant natural bodies of soil in the survey area, they drew the boundaries of these bodies on aerial photographs and Custom Soil Resource Report 6 identified each as a specific map unit. Aerial photographs show trees, buildings, fields, roads, and rivers, all of which help in locating boundaries accurately. Custom Soil Resource Report 7 Soil Map The soil map section includes the soil map for the defined area of interest, a list of soil map units on the map and extent of each map unit, and cartographic symbols displayed on the map. Also presented are various metadata about data used to produce the map, and a description of each soil map unit. 8 9 Custom Soil Resource Report Soil Map 37 0 6 1 1 0 37 0 6 1 4 0 37 0 6 1 7 0 37 0 6 2 0 0 37 0 6 2 3 0 37 0 6 2 6 0 37 0 6 2 9 0 37 0 6 3 2 0 37 0 6 3 5 0 37 0 6 0 8 0 37 0 6 1 1 0 37 0 6 1 4 0 37 0 6 1 7 0 37 0 6 2 0 0 37 0 6 2 3 0 37 0 6 2 6 0 37 0 6 2 9 0 37 0 6 3 2 0 37 0 6 3 5 0 488060 488090 488120 488150 488180 488210 488240 488060 488090 488120 488150 488180 488210 488240 33° 29' 47'' N 11 7 ° 7 ' 4 3 ' ' W 33° 29' 47'' N 11 7 ° 7 ' 3 5 ' ' W 33° 29' 39'' N 11 7 ° 7 ' 4 3 ' ' W 33° 29' 39'' N 11 7 ° 7 ' 3 5 ' ' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 11N WGS84 0 50 100 200 300 Feet 0 20 40 80 120 Meters Map Scale: 1:1,350 if printed on A portrait (8.5" x 11") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:15,800. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Western Riverside Area, California Survey Area Data: Version 12, Sep 16, 2019 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: May 15, 2018—Jun 25, 2018 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Custom Soil Resource Report 10 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI GzG Gullied land 2.0 82.1% RmE3 Ramona and Buren sandy loams, 15 to 25 percent slopes, severely eroded 0.4 17.9% Totals for Area of Interest 2.4 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, Custom Soil Resource Report 11 onsite investigation is needed to define and locate the soils and miscellaneous areas. An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps. The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha-Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha-Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. Custom Soil Resource Report 12 Western Riverside Area, California GzG—Gullied land Map Unit Composition Gullied land: 100 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Gullied Land Setting Landform: Terraces Landform position (two-dimensional): Backslope Landform position (three-dimensional): Riser Down-slope shape: Concave Across-slope shape: Concave Typical profile H1 - 0 to 60 inches: variable Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 8 Hydric soil rating: No RmE3—Ramona and Buren sandy loams, 15 to 25 percent slopes, severely eroded Map Unit Setting National map unit symbol: hcyj Elevation: 250 to 3,500 feet Mean annual precipitation: 10 to 20 inches Mean annual air temperature: 63 degrees F Frost-free period: 230 to 320 days Farmland classification: Not prime farmland Map Unit Composition Ramona and similar soils: 45 percent Buren and similar soils: 40 percent Minor components: 15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Ramona Setting Landform: Alluvial fans, terraces Landform position (three-dimensional): Tread Down-slope shape: Concave Across-slope shape: Convex Parent material: Alluvium derived from granite Typical profile H1 - 0 to 8 inches: sandy loam Custom Soil Resource Report 13 H2 - 8 to 17 inches: fine sandy loam H3 - 17 to 68 inches: sandy clay loam H4 - 68 to 74 inches: gravelly sandy loam Properties and qualities Slope: 15 to 25 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Well drained Runoff class: Very high Capacity of the most limiting layer to transmit water (Ksat): Moderately high (0.20 to 0.57 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Calcium carbonate, maximum in profile: 1 percent Available water storage in profile: Moderate (about 8.4 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 6e Hydrologic Soil Group: C Ecological site: LOAMY (1975) (R019XD029CA) Hydric soil rating: No Description of Buren Setting Landform: Alluvial fans, terraces Landform position (three-dimensional): Tread Down-slope shape: Linear Across-slope shape: Convex, linear Parent material: Alluvium Typical profile H1 - 0 to 12 inches: sandy loam H2 - 12 to 28 inches: loam H3 - 28 to 37 inches: loam H4 - 37 to 52 inches: cemented Properties and qualities Slope: 15 to 25 percent Depth to restrictive feature: 37 to 40 inches to duripan Natural drainage class: Well drained Runoff class: Very high Capacity of the most limiting layer to transmit water (Ksat): Very low to moderately low (0.00 to 0.06 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Calcium carbonate, maximum in profile: 1 percent Salinity, maximum in profile: Nonsaline to slightly saline (0.0 to 4.0 mmhos/cm) Available water storage in profile: Low (about 5.5 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 6e Hydrologic Soil Group: C Custom Soil Resource Report 14 Ecological site: LOAMY (1975) (R019XD029CA) Hydric soil rating: No Minor Components Ramona Percent of map unit: 5 percent Hydric soil rating: No Buren Percent of map unit: 5 percent Hydric soil rating: No Hanford Percent of map unit: 5 percent Hydric soil rating: No Custom Soil Resource Report 15 References American Association of State Highway and Transportation Officials (AASHTO). 2004. Standard specifications for transportation materials and methods of sampling and testing. 24th edition. American Society for Testing and Materials (ASTM). 2005. Standard classification of soils for engineering purposes. ASTM Standard D2487-00. Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deep-water habitats of the United States. U.S. Fish and Wildlife Service FWS/OBS-79/31. Federal Register. July 13, 1994. Changes in hydric soils of the United States. Federal Register. September 18, 2002. Hydric soils of the United States. Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric soils in the United States. National Research Council. 1995. Wetlands: Characteristics and boundaries. Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S. Department of Agriculture Handbook 18. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/national/soils/?cid=nrcs142p2_054262 Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service, U.S. Department of Agriculture Handbook 436. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053577 Soil Survey Staff. 2010. Keys to soil taxonomy. 11th edition. U.S. Department of Agriculture, Natural Resources Conservation Service. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053580 Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and Delaware Department of Natural Resources and Environmental Control, Wetlands Section. United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Waterways Experiment Station Technical Report Y-87-1. United States Department of Agriculture, Natural Resources Conservation Service. National forestry manual. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ home/?cid=nrcs142p2_053374 United States Department of Agriculture, Natural Resources Conservation Service. National range and pasture handbook. http://www.nrcs.usda.gov/wps/portal/nrcs/ detail/national/landuse/rangepasture/?cid=stelprdb1043084 16 United States Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 430-VI. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/soils/scientists/?cid=nrcs142p2_054242 United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/? cid=nrcs142p2_053624 United States Department of Agriculture, Soil Conservation Service. 1961. Land capability classification. U.S. Department of Agriculture Handbook 210. http:// www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052290.pdf Custom Soil Resource Report 17 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 2 - 1 - ATTACHMENT 2: EXISTING CONDITIONS CALCULATIONS This attachment contains the existing conditions calculations. Please see the attached calculations. HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 2 - 2 - EXISTING CONDITIONS – CONFLUENCE POINT A 100 YEAR DESIGN STORM EVENT Riverside County Rational Hydrology Program CIVILCADD/CIVILDESIGN Engineering Software,(c) 1989 - 2014 Version 9.0 Rational Hydrology Study Date: 09/13/20 File:mcgovernexb1d3.out ------------------------------------------------------------------------ ********* Hydrology Study Control Information ********** English (in-lb) Units used in input data file ------------------------------------------------------------------------ Rational Method Hydrology Program based on Riverside County Flood Control & Water Conservation District 1978 hydrology manual Storm event (year) = 100.00 Antecedent Moisture Condition = 3 Standard intensity-duration curves data (Plate D-4.1) For the [ Murrieta,Tmc,Rnch CaNorco ] area used. 10 year storm 10 minute intensity = 2.360(In/Hr) 10 year storm 60 minute intensity = 0.880(In/Hr) 100 year storm 10 minute intensity = 3.480(In/Hr) 100 year storm 60 minute intensity = 1.300(In/Hr) Storm event year = 100.0 Calculated rainfall intensity data: 1 hour intensity = 1.300(In/Hr) Slope of intensity duration curve = 0.5500 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.110 to Point/Station 1.210 **** INITIAL AREA EVALUATION **** ______________________________________________________________________ Initial area flow distance = 100.000(Ft.) Top (of initial area) elevation = 1252.000(Ft.) Bottom (of initial area) elevation = 1241.000(Ft.) Difference in elevation = 11.000(Ft.) Slope = 0.11000 s(percent)= 11.00 TC = k(0.530)*[(length^3)/(elevation change)]^0.2 Initial area time of concentration = 5.200 min. Rainfall intensity = 4.990(In/Hr) for a 100.0 year storm UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.886 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Initial subarea runoff = 0.951(CFS) Total initial stream area = 0.215(Ac.) Pervious area fraction = 1.000 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 2 - 3 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.210 to Point/Station 1.310 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Estimated mean flow rate at midpoint of channel = 1.952(CFS) Depth of flow = 0.174(Ft.), Average velocity = 3.400(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 1.00 2 30.00 0.00 3 32.00 0.25 4 35.00 1.00 Manning's 'N' friction factor = 0.020 ----------------------------------------------------------------- Sub-Channel flow = 1.952(CFS) ' ' flow top width = 6.606(Ft.) ' ' velocity= 3.400(Ft/s) ' ' area = 0.574(Sq.Ft) ' ' Froude number = 2.032 Upstream point elevation = 1241.000(Ft.) Downstream point elevation = 1226.000(Ft.) Flow length = 275.000(Ft.) Travel time = 1.35 min. Time of concentration = 6.55 min. Depth of flow = 0.174(Ft.) Average velocity = 3.400(Ft/s) Total irregular channel flow = 1.952(CFS) Irregular channel normal depth above invert elev. = 0.174(Ft.) Average velocity of channel(s) = 3.400(Ft/s) Adding area flow to channel UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.884 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 4.396(In/Hr) for a 100.0 year storm Subarea runoff = 1.936(CFS) for 0.498(Ac.) Total runoff = 2.886(CFS) Total area = 0.713(Ac.) Depth of flow = 0.201(Ft.), Average velocity = 3.749(Ft/s) HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 2 - 4 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.310 to Point/Station 1.610 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Estimated mean flow rate at midpoint of channel = 4.082(CFS) Depth of flow = 0.316(Ft.), Average velocity = 8.534(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 3.00 2 0.90 2.00 3 1.30 1.00 4 1.90 0.50 5 5.60 0.00 6 6.70 0.50 7 7.50 1.00 8 8.10 2.00 9 9.40 3.00 Manning's 'N' friction factor = 0.020 ----------------------------------------------------------------- Sub-Channel flow = 4.082(CFS) ' ' flow top width = 3.031(Ft.) ' ' velocity= 8.534(Ft/s) ' ' area = 0.478(Sq.Ft) ' ' Froude number = 3.785 Upstream point elevation = 1226.000(Ft.) Downstream point elevation = 1185.000(Ft.) Flow length = 255.000(Ft.) Travel time = 0.50 min. Time of concentration = 7.05 min. Depth of flow = 0.316(Ft.) Average velocity = 8.534(Ft/s) Total irregular channel flow = 4.082(CFS) Irregular channel normal depth above invert elev. = 0.316(Ft.) Average velocity of channel(s) = 8.534(Ft/s) Adding area flow to channel UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.883 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 4.222(In/Hr) for a 100.0 year storm Subarea runoff = 2.294(CFS) for 0.615(Ac.) Total runoff = 5.180(CFS) Total area = 1.328(Ac.) Depth of flow = 0.345(Ft.), Average velocity = 9.058(Ft/s) HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 2 - 5 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.110 to Point/Station 1.610 **** CONFLUENCE OF MINOR STREAMS **** ______________________________________________________________________ Along Main Stream number: 1 in normal stream number 1 Stream flow area = 1.328(Ac.) Runoff from this stream = 5.180(CFS) Time of concentration = 7.05 min. Rainfall intensity = 4.222(In/Hr) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.410 to Point/Station 1.510 **** INITIAL AREA EVALUATION **** ______________________________________________________________________ Initial area flow distance = 100.000(Ft.) Top (of initial area) elevation = 1250.000(Ft.) Bottom (of initial area) elevation = 1231.000(Ft.) Difference in elevation = 19.000(Ft.) Slope = 0.19000 s(percent)= 19.00 TC = k(0.530)*[(length^3)/(elevation change)]^0.2 Warning: TC computed to be less than 5 min.; program is assuming the time of concentration is 5 minutes. Initial area time of concentration = 5.000 min. Rainfall intensity = 5.099(In/Hr) for a 100.0 year storm UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.886 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Initial subarea runoff = 0.949(CFS) Total initial stream area = 0.210(Ac.) Pervious area fraction = 1.000 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.510 to Point/Station 1.610 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Estimated mean flow rate at midpoint of channel = 4.554(CFS) Depth of flow = 0.215(Ft.), Average velocity = 7.354(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 1.00 2 7.00 0.50 3 8.50 0.00 4 10.10 0.00 5 19.00 1.00 Manning's 'N' friction factor = 0.020 ----------------------------------------------------------------- HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 2 - 6 - Sub-Channel flow = 4.554(CFS) ' ' flow top width = 4.159(Ft.) ' ' velocity= 7.354(Ft/s) ' ' area = 0.619(Sq.Ft) ' ' Froude number = 3.359 Upstream point elevation = 1231.000(Ft.) Downstream point elevation = 1185.000(Ft.) Flow length = 365.000(Ft.) Travel time = 0.83 min. Time of concentration = 5.83 min. Depth of flow = 0.215(Ft.) Average velocity = 7.354(Ft/s) Total irregular channel flow = 4.554(CFS) Irregular channel normal depth above invert elev. = 0.215(Ft.) Average velocity of channel(s) = 7.354(Ft/s) Adding area flow to channel UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.885 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 4.687(In/Hr) for a 100.0 year storm Subarea runoff = 7.127(CFS) for 1.718(Ac.) Total runoff = 8.076(CFS) Total area = 1.928(Ac.) Depth of flow = 0.285(Ft.), Average velocity = 8.592(Ft/s) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.410 to Point/Station 1.610 **** CONFLUENCE OF MINOR STREAMS **** ______________________________________________________________________ Along Main Stream number: 1 in normal stream number 2 Stream flow area = 1.928(Ac.) Runoff from this stream = 8.076(CFS) Time of concentration = 5.83 min. Rainfall intensity = 4.687(In/Hr) Summary of stream data: Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr) 1 5.180 7.05 4.222 2 8.076 5.83 4.687 Largest stream flow has longer or shorter time of concentration Qp = 8.076 + sum of Qa Tb/Ta 5.180 * 0.827 = 4.284 Qp = 12.360 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 2 - 7 - Total of 2 streams to confluence: Flow rates before confluence point: 5.180 8.076 Area of streams before confluence: 1.328 1.928 Results of confluence: Total flow rate = 12.360(CFS) Time of concentration = 5.827 min. Effective stream area after confluence = 3.256(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.610 to Point/Station 1.820 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Estimated mean flow rate at midpoint of channel = 13.676(CFS) Depth of flow = 0.392(Ft.), Average velocity = 5.925(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 1.00 2 4.60 0.50 3 6.60 0.25 4 10.90 0.00 5 14.40 0.25 6 18.00 0.50 7 28.00 1.00 Manning's 'N' friction factor = 0.020 ----------------------------------------------------------------- Sub-Channel flow = 13.676(CFS) ' ' flow top width = 10.980(Ft.) ' ' velocity= 5.925(Ft/s) ' ' area = 2.308(Sq.Ft) ' ' Froude number = 2.277 Upstream point elevation = 1185.000(Ft.) Downstream point elevation = 1173.000(Ft.) Flow length = 235.000(Ft.) Travel time = 0.66 min. Time of concentration = 6.49 min. Depth of flow = 0.392(Ft.) Average velocity = 5.925(Ft/s) Total irregular channel flow = 13.676(CFS) Irregular channel normal depth above invert elev. = 0.392(Ft.) Average velocity of channel(s) = 5.925(Ft/s) Adding area flow to channel UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.884 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 2 - 8 - Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 4.418(In/Hr) for a 100.0 year storm Subarea runoff = 2.707(CFS) for 0.693(Ac.) Total runoff = 15.068(CFS) Total area = 3.949(Ac.) Depth of flow = 0.407(Ft.), Average velocity = 6.085(Ft/s) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.110 to Point/Station 1.820 **** CONFLUENCE OF MINOR STREAMS **** ______________________________________________________________________ Along Main Stream number: 1 in normal stream number 1 Stream flow area = 3.949(Ac.) Runoff from this stream = 15.068(CFS) Time of concentration = 6.49 min. Rainfall intensity = 4.418(In/Hr) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.710 to Point/Station 1.810 **** INITIAL AREA EVALUATION **** ______________________________________________________________________ Initial area flow distance = 100.000(Ft.) Top (of initial area) elevation = 1230.500(Ft.) Bottom (of initial area) elevation = 1204.000(Ft.) Difference in elevation = 26.500(Ft.) Slope = 0.26500 s(percent)= 26.50 TC = k(0.530)*[(length^3)/(elevation change)]^0.2 Warning: TC computed to be less than 5 min.; program is assuming the time of concentration is 5 minutes. Initial area time of concentration = 5.000 min. Rainfall intensity = 5.099(In/Hr) for a 100.0 year storm UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.886 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Initial subarea runoff = 0.917(CFS) Total initial stream area = 0.203(Ac.) Pervious area fraction = 1.000 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 2 - 9 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.810 to Point/Station 1.820 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Estimated mean flow rate at midpoint of channel = 1.814(CFS) Depth of flow = 0.132(Ft.), Average velocity = 5.509(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 1.00 2 4.60 0.50 3 8.30 0.00 4 15.90 0.25 5 17.80 0.50 6 21.70 1.00 Manning's 'N' friction factor = 0.020 ----------------------------------------------------------------- Sub-Channel flow = 1.814(CFS) ' ' flow top width = 4.990(Ft.) ' ' velocity= 5.509(Ft/s) ' ' area = 0.329(Sq.Ft) ' ' Froude number = 3.779 Upstream point elevation = 1204.000(Ft.) Downstream point elevation = 1173.000(Ft.) Flow length = 150.000(Ft.) Travel time = 0.45 min. Time of concentration = 5.45 min. Depth of flow = 0.132(Ft.) Average velocity = 5.509(Ft/s) Total irregular channel flow = 1.814(CFS) Irregular channel normal depth above invert elev. = 0.132(Ft.) Average velocity of channel(s) = 5.509(Ft/s) Adding area flow to channel UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.886 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 4.861(In/Hr) for a 100.0 year storm Subarea runoff = 1.709(CFS) for 0.397(Ac.) Total runoff = 2.626(CFS) Total area = 0.600(Ac.) Depth of flow = 0.152(Ft.), Average velocity = 6.042(Ft/s) HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 2 - 10 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.710 to Point/Station 1.820 **** CONFLUENCE OF MINOR STREAMS **** ______________________________________________________________________ Along Main Stream number: 1 in normal stream number 2 Stream flow area = 0.600(Ac.) Runoff from this stream = 2.626(CFS) Time of concentration = 5.45 min. Rainfall intensity = 4.861(In/Hr) Summary of stream data: Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr) 1 15.068 6.49 4.418 2 2.626 5.45 4.861 Largest stream flow has longer time of concentration Qp = 15.068 + sum of Qb Ia/Ib 2.626 * 0.909 = 2.387 Qp = 17.455 Total of 2 streams to confluence: Flow rates before confluence point: 15.068 2.626 Area of streams before confluence: 3.949 0.600 Results of confluence: Total flow rate = 17.455(CFS) Time of concentration = 6.488 min. Effective stream area after confluence = 4.549(Ac.) End of computations, total study area = 4.55 (Ac.) The following figures may be used for a unit hydrograph study of the same area. Area averaged pervious area fraction(Ap) = 1.000 Area averaged RI index number = 86.0 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 2 - 11 - EXISTING CONDITIONS – CONFLUENCE POINT B 100 YEAR DESIGN STORM EVENT Riverside County Rational Hydrology Program CIVILCADD/CIVILDESIGN Engineering Software,(c) 1989 - 2014 Version 9.0 Rational Hydrology Study Date: 09/13/20 File:mcgovernexb2d3.out ------------------------------------------------------------------------ ********* Hydrology Study Control Information ********** English (in-lb) Units used in input data file ------------------------------------------------------------------------ Rational Method Hydrology Program based on Riverside County Flood Control & Water Conservation District 1978 hydrology manual Storm event (year) = 100.00 Antecedent Moisture Condition = 3 Standard intensity-duration curves data (Plate D-4.1) For the [ Murrieta,Tmc,Rnch CaNorco ] area used. 10 year storm 10 minute intensity = 2.360(In/Hr) 10 year storm 60 minute intensity = 0.880(In/Hr) 100 year storm 10 minute intensity = 3.480(In/Hr) 100 year storm 60 minute intensity = 1.300(In/Hr) Storm event year = 100.0 Calculated rainfall intensity data: 1 hour intensity = 1.300(In/Hr) Slope of intensity duration curve = 0.5500 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 2.110 to Point/Station 2.210 **** INITIAL AREA EVALUATION **** ______________________________________________________________________ Initial area flow distance = 100.000(Ft.) Top (of initial area) elevation = 1241.000(Ft.) Bottom (of initial area) elevation = 1218.000(Ft.) Difference in elevation = 23.000(Ft.) Slope = 0.23000 s(percent)= 23.00 TC = k(0.530)*[(length^3)/(elevation change)]^0.2 Warning: TC computed to be less than 5 min.; program is assuming the time of concentration is 5 minutes. Initial area time of concentration = 5.000 min. Rainfall intensity = 5.099(In/Hr) for a 100.0 year storm UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.886 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Initial subarea runoff = 0.615(CFS) Total initial stream area = 0.136(Ac.) Pervious area fraction = 1.000 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 2 - 12 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 2.210 to Point/Station 2.220 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Estimated mean flow rate at midpoint of channel = 1.453(CFS) Depth of flow = 0.138(Ft.), Average velocity = 6.685(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 1.00 2 7.30 0.00 3 15.00 0.50 4 22.50 1.00 Manning's 'N' friction factor = 0.020 ----------------------------------------------------------------- Sub-Channel flow = 1.453(CFS) ' ' flow top width = 3.141(Ft.) ' ' velocity= 6.685(Ft/s) ' ' area = 0.217(Sq.Ft) ' ' Froude number = 4.479 Upstream point elevation = 1218.000(Ft.) Downstream point elevation = 1175.000(Ft.) Flow length = 150.000(Ft.) Travel time = 0.37 min. Time of concentration = 5.37 min. Depth of flow = 0.138(Ft.) Average velocity = 6.685(Ft/s) Total irregular channel flow = 1.453(CFS) Irregular channel normal depth above invert elev. = 0.138(Ft.) Average velocity of channel(s) = 6.685(Ft/s) Adding area flow to channel UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.886 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 4.901(In/Hr) for a 100.0 year storm Subarea runoff = 1.610(CFS) for 0.371(Ac.) Total runoff = 2.225(CFS) Total area = 0.507(Ac.) Depth of flow = 0.162(Ft.), Average velocity = 7.436(Ft/s) End of computations, total study area = 0.51 (Ac.) The following figures may be used for a unit hydrograph study of the same area. Area averaged pervious area fraction(Ap) = 1.000 Area averaged RI index number = 86.0 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 2 - 13 - EXISTING CONDITIONS – CONFLUENCE POINT C 100 YEAR DESIGN STORM EVENT Riverside County Rational Hydrology Program CIVILCADD/CIVILDESIGN Engineering Software,(c) 1989 - 2014 Version 9.0 Rational Hydrology Study Date: 09/13/20 File:mcgovernexb3d3.out ------------------------------------------------------------------------ ********* Hydrology Study Control Information ********** English (in-lb) Units used in input data file ------------------------------------------------------------------------ Rational Method Hydrology Program based on Riverside County Flood Control & Water Conservation District 1978 hydrology manual Storm event (year) = 100.00 Antecedent Moisture Condition = 3 Standard intensity-duration curves data (Plate D-4.1) For the [ Murrieta,Tmc,Rnch CaNorco ] area used. 10 year storm 10 minute intensity = 2.360(In/Hr) 10 year storm 60 minute intensity = 0.880(In/Hr) 100 year storm 10 minute intensity = 3.480(In/Hr) 100 year storm 60 minute intensity = 1.300(In/Hr) Storm event year = 100.0 Calculated rainfall intensity data: 1 hour intensity = 1.300(In/Hr) Slope of intensity duration curve = 0.5500 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 3.110 to Point/Station 3.210 **** INITIAL AREA EVALUATION **** ______________________________________________________________________ Initial area flow distance = 95.000(Ft.) Top (of initial area) elevation = 1241.000(Ft.) Bottom (of initial area) elevation = 1210.000(Ft.) Difference in elevation = 31.000(Ft.) Slope = 0.32632 s(percent)= 32.63 TC = k(0.530)*[(length^3)/(elevation change)]^0.2 Warning: TC computed to be less than 5 min.; program is assuming the time of concentration is 5 minutes. Initial area time of concentration = 5.000 min. Rainfall intensity = 5.099(In/Hr) for a 100.0 year storm UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.886 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Initial subarea runoff = 0.484(CFS) Total initial stream area = 0.107(Ac.) Pervious area fraction = 1.000 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 2 - 14 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 3.210 to Point/Station 3.220 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Estimated mean flow rate at midpoint of channel = 0.960(CFS) Depth of flow = 0.162(Ft.), Average velocity = 6.747(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 1.00 2 5.60 0.25 3 6.80 0.00 4 8.30 0.25 5 12.30 1.00 Manning's 'N' friction factor = 0.020 ----------------------------------------------------------------- Sub-Channel flow = 0.960(CFS) ' ' flow top width = 1.753(Ft.) ' ' velocity= 6.747(Ft/s) ' ' area = 0.142(Sq.Ft) ' ' Froude number = 4.173 Upstream point elevation = 1210.000(Ft.) Downstream point elevation = 1174.000(Ft.) Flow length = 150.000(Ft.) Travel time = 0.37 min. Time of concentration = 5.37 min. Depth of flow = 0.162(Ft.) Average velocity = 6.747(Ft/s) Total irregular channel flow = 0.960(CFS) Irregular channel normal depth above invert elev. = 0.162(Ft.) Average velocity of channel(s) = 6.747(Ft/s) Adding area flow to channel UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.886 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 4.902(In/Hr) for a 100.0 year storm Subarea runoff = 0.916(CFS) for 0.211(Ac.) Total runoff = 1.400(CFS) Total area = 0.318(Ac.) Depth of flow = 0.187(Ft.), Average velocity = 7.413(Ft/s) End of computations, total study area = 0.32 (Ac.) The following figures may be used for a unit hydrograph study of the same area. Area averaged pervious area fraction(Ap) = 1.000 Area averaged RI index number = 86.0 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 1 - ATTACHMENT 3: PROPOSED CONDITIONS CALCULATIONS This attachment contains the proposed conditions calculations. Please see the attached calculations. HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 2 - PROPOSED CONDITIONS – CONFLUENCE POINT A 100 YEAR DESIGN STORM EVENT Riverside County Rational Hydrology Program CIVILCADD/CIVILDESIGN Engineering Software,(c) 1989 - 2014 Version 9.0 Rational Hydrology Study Date: 09/13/20 File:mcgovernprb1d3.out ------------------------------------------------------------------------ ********* Hydrology Study Control Information ********** English (in-lb) Units used in input data file ------------------------------------------------------------------------ Rational Method Hydrology Program based on Riverside County Flood Control & Water Conservation District 1978 hydrology manual Storm event (year) = 100.00 Antecedent Moisture Condition = 3 Standard intensity-duration curves data (Plate D-4.1) For the [ Murrieta,Tmc,Rnch CaNorco ] area used. 10 year storm 10 minute intensity = 2.360(In/Hr) 10 year storm 60 minute intensity = 0.880(In/Hr) 100 year storm 10 minute intensity = 3.480(In/Hr) 100 year storm 60 minute intensity = 1.300(In/Hr) Storm event year = 100.0 Calculated rainfall intensity data: 1 hour intensity = 1.300(In/Hr) Slope of intensity duration curve = 0.5500 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.110 to Point/Station 1.210 **** INITIAL AREA EVALUATION **** ______________________________________________________________________ Initial area flow distance = 100.000(Ft.) Top (of initial area) elevation = 1252.000(Ft.) Bottom (of initial area) elevation = 1241.000(Ft.) Difference in elevation = 11.000(Ft.) Slope = 0.11000 s(percent)= 11.00 TC = k(0.530)*[(length^3)/(elevation change)]^0.2 Initial area time of concentration = 5.200 min. Rainfall intensity = 4.990(In/Hr) for a 100.0 year storm UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.886 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Initial subarea runoff = 0.959(CFS) Total initial stream area = 0.217(Ac.) Pervious area fraction = 1.000 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 3 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.210 to Point/Station 1.310 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Estimated mean flow rate at midpoint of channel = 1.819(CFS) Depth of flow = 0.169(Ft.), Average velocity = 3.341(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 1.00 2 30.00 0.00 3 32.00 0.25 4 35.00 1.00 Manning's 'N' friction factor = 0.020 ----------------------------------------------------------------- Sub-Channel flow = 1.819(CFS) ' ' flow top width = 6.433(Ft.) ' ' velocity= 3.341(Ft/s) ' ' area = 0.544(Sq.Ft) ' ' Froude number = 2.024 Upstream point elevation = 1241.000(Ft.) Downstream point elevation = 1226.000(Ft.) Flow length = 275.000(Ft.) Travel time = 1.37 min. Time of concentration = 6.57 min. Depth of flow = 0.169(Ft.) Average velocity = 3.341(Ft/s) Total irregular channel flow = 1.819(CFS) Irregular channel normal depth above invert elev. = 0.169(Ft.) Average velocity of channel(s) = 3.341(Ft/s) Adding area flow to channel UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.884 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 4.387(In/Hr) for a 100.0 year storm Subarea runoff = 1.660(CFS) for 0.428(Ac.) Total runoff = 2.619(CFS) Total area = 0.645(Ac.) Depth of flow = 0.194(Ft.), Average velocity = 3.659(Ft/s) HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 4 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.310 to Point/Station 1.320 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Estimated mean flow rate at midpoint of channel = 2.890(CFS) Depth of flow = 0.215(Ft.), Average velocity = 7.086(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 0.75 2 6.30 0.00 3 13.20 0.75 Manning's 'N' friction factor = 0.025 ----------------------------------------------------------------- Sub-Channel flow = 2.890(CFS) ' ' flow top width = 3.789(Ft.) ' ' velocity= 7.086(Ft/s) ' ' area = 0.408(Sq.Ft) ' ' Froude number = 3.806 Upstream point elevation = 1226.000(Ft.) Downstream point elevation = 1219.000(Ft.) Flow length = 25.000(Ft.) Travel time = 0.06 min. Time of concentration = 6.63 min. Depth of flow = 0.215(Ft.) Average velocity = 7.086(Ft/s) Total irregular channel flow = 2.890(CFS) Irregular channel normal depth above invert elev. = 0.215(Ft.) Average velocity of channel(s) = 7.086(Ft/s) Adding area flow to channel UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.884 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 4.366(In/Hr) for a 100.0 year storm Subarea runoff = 0.513(CFS) for 0.133(Ac.) Total runoff = 3.133(CFS) Total area = 0.778(Ac.) Depth of flow = 0.222(Ft.), Average velocity = 7.231(Ft/s) HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 5 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.320 to Point/Station 1.330 **** IMPROVED CHANNEL TRAVEL TIME **** ______________________________________________________________________ Upstream point elevation = 1219.000(Ft.) Downstream point elevation = 1218.000(Ft.) Channel length thru subarea = 10.000(Ft.) Channel base width = 2.500(Ft.) Slope or 'Z' of left channel bank = 3.000 Slope or 'Z' of right channel bank = 3.000 Manning's 'N' = 0.044 Maximum depth of channel = 1.000(Ft.) Flow(q) thru subarea = 3.133(CFS) Depth of flow = 0.258(Ft.), Average velocity = 3.707(Ft/s) Channel flow top width = 4.049(Ft.) Flow Velocity = 3.71(Ft/s) Travel time = 0.04 min. Time of concentration = 6.68 min. Sub-Channel No. 1 Critical depth = 0.320(Ft.) ' ' ' Critical flow top width = 4.422(Ft.) ' ' ' Critical flow velocity= 2.826(Ft/s) ' ' ' Critical flow area = 1.109(Sq.Ft) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.330 to Point/Station 1.540 **** PIPEFLOW TRAVEL TIME (User specified size) **** ______________________________________________________________________ Upstream point/station elevation = 1218.000(Ft.) Downstream point/station elevation = 1203.800(Ft.) Pipe length = 90.00(Ft.) Manning's N = 0.013 No. of pipes = 1 Required pipe flow = 3.133(CFS) Given pipe size = 18.00(In.) Calculated individual pipe flow = 3.133(CFS) Normal flow depth in pipe = 3.34(In.) Flow top width inside pipe = 13.99(In.) Critical Depth = 8.10(In.) Pipe flow velocity = 13.88(Ft/s) Travel time through pipe = 0.11 min. Time of concentration (TC) = 6.78 min. HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 6 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.110 to Point/Station 1.540 **** CONFLUENCE OF MINOR STREAMS **** ______________________________________________________________________ Along Main Stream number: 1 in normal stream number 1 Stream flow area = 0.778(Ac.) Runoff from this stream = 3.133(CFS) Time of concentration = 6.78 min. Rainfall intensity = 4.311(In/Hr) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.410 to Point/Station 1.510 **** INITIAL AREA EVALUATION **** ______________________________________________________________________ Initial area flow distance = 100.000(Ft.) Top (of initial area) elevation = 1239.500(Ft.) Bottom (of initial area) elevation = 1230.500(Ft.) Difference in elevation = 9.000(Ft.) Slope = 0.09000 s(percent)= 9.00 TC = k(0.480)*[(length^3)/(elevation change)]^0.2 Warning: TC computed to be less than 5 min.; program is assuming the time of concentration is 5 minutes. Initial area time of concentration = 5.000 min. Rainfall intensity = 5.099(In/Hr) for a 100.0 year storm SINGLE FAMILY (1 Acre Lot) Runoff Coefficient = 0.867 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 84.40 Pervious area fraction = 0.800; Impervious fraction = 0.200 Initial subarea runoff = 0.217(CFS) Total initial stream area = 0.049(Ac.) Pervious area fraction = 0.800 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 7 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.510 to Point/Station 1.520 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Estimated mean flow rate at midpoint of channel = 1.156(CFS) Depth of flow = 0.112(Ft.), Average velocity = 4.593(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 0.50 2 20.00 0.00 3 20.00 0.50 Manning's 'N' friction factor = 0.013 ----------------------------------------------------------------- Sub-Channel flow = 1.156(CFS) ' ' flow top width = 4.487(Ft.) ' ' velocity= 4.594(Ft/s) ' ' area = 0.252(Sq.Ft) ' ' Froude number = 3.418 Upstream point elevation = 1230.500(Ft.) Downstream point elevation = 1220.000(Ft.) Flow length = 135.000(Ft.) Travel time = 0.49 min. Time of concentration = 5.49 min. Depth of flow = 0.112(Ft.) Average velocity = 4.593(Ft/s) Total irregular channel flow = 1.156(CFS) Irregular channel normal depth above invert elev. = 0.112(Ft.) Average velocity of channel(s) = 4.593(Ft/s) Adding area flow to channel SINGLE FAMILY (1 Acre Lot) Runoff Coefficient = 0.865 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 84.40 Pervious area fraction = 0.800; Impervious fraction = 0.200 Rainfall intensity = 4.844(In/Hr) for a 100.0 year storm Subarea runoff = 1.781(CFS) for 0.425(Ac.) Total runoff = 1.997(CFS) Total area = 0.474(Ac.) Depth of flow = 0.138(Ft.), Average velocity = 5.267(Ft/s) HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 8 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.520 to Point/Station 1.530 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Depth of flow = 0.080(Ft.), Average velocity = 1.271(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 0.50 2 0.50 0.00 3 20.00 0.00 4 20.50 0.50 Manning's 'N' friction factor = 0.025 ----------------------------------------------------------------- Sub-Channel flow = 1.998(CFS) ' ' flow top width = 19.661(Ft.) ' ' velocity= 1.271(Ft/s) ' ' area = 1.572(Sq.Ft) ' ' Froude number = 0.792 Upstream point elevation = 1220.000(Ft.) Downstream point elevation = 1219.400(Ft.) Flow length = 45.000(Ft.) Travel time = 0.59 min. Time of concentration = 6.08 min. Depth of flow = 0.080(Ft.) Average velocity = 1.271(Ft/s) Total irregular channel flow = 1.997(CFS) Irregular channel normal depth above invert elev. = 0.080(Ft.) Average velocity of channel(s) = 1.271(Ft/s) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.530 to Point/Station 1.540 **** PIPEFLOW TRAVEL TIME (User specified size) **** ______________________________________________________________________ Upstream point/station elevation = 1206.900(Ft.) Downstream point/station elevation = 1203.300(Ft.) Pipe length = 50.00(Ft.) Manning's N = 0.013 No. of pipes = 1 Required pipe flow = 1.997(CFS) Given pipe size = 8.00(In.) Calculated individual pipe flow = 1.997(CFS) Normal flow depth in pipe = 4.54(In.) Flow top width inside pipe = 7.93(In.) Critical Depth = 7.52(In.) Pipe flow velocity = 9.77(Ft/s) Travel time through pipe = 0.09 min. Time of concentration (TC) = 6.17 min. HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 9 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.410 to Point/Station 1.540 **** CONFLUENCE OF MINOR STREAMS **** ______________________________________________________________________ Along Main Stream number: 1 in normal stream number 2 Stream flow area = 0.474(Ac.) Runoff from this stream = 1.997(CFS) Time of concentration = 6.17 min. Rainfall intensity = 4.544(In/Hr) Summary of stream data: Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr) 1 3.133 6.78 4.311 2 1.997 6.17 4.544 Largest stream flow has longer time of concentration Qp = 3.133 + sum of Qb Ia/Ib 1.997 * 0.949 = 1.895 Qp = 5.028 Total of 2 streams to confluence: Flow rates before confluence point: 3.133 1.997 Area of streams before confluence: 0.778 0.474 Results of confluence: Total flow rate = 5.028(CFS) Time of concentration = 6.784 min. Effective stream area after confluence = 1.252(Ac.) HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 10 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.540 to Point/Station 1.610 **** IMPROVED CHANNEL TRAVEL TIME **** ______________________________________________________________________ Upstream point elevation = 1203.300(Ft.) Downstream point elevation = 1203.000(Ft.) Channel length thru subarea = 10.000(Ft.) Channel base width = 2.500(Ft.) Slope or 'Z' of left channel bank = 3.000 Slope or 'Z' of right channel bank = 3.000 Manning's 'N' = 0.044 Maximum depth of channel = 1.000(Ft.) Flow(q) thru subarea = 5.028(CFS) Depth of flow = 0.462(Ft.), Average velocity = 2.800(Ft/s) Channel flow top width = 5.272(Ft.) Flow Velocity = 2.80(Ft/s) Travel time = 0.06 min. Time of concentration = 6.84 min. Sub-Channel No. 1 Critical depth = 0.422(Ft.) ' ' ' Critical flow top width = 5.031(Ft.) ' ' ' Critical flow velocity= 3.165(Ft/s) ' ' ' Critical flow area = 1.589(Sq.Ft) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.610 to Point/Station 1.103 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Estimated mean flow rate at midpoint of channel = 9.301(CFS) Depth of flow = 0.713(Ft.), Average velocity = 14.624(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 1.00 2 1.25 0.00 3 2.50 1.00 Manning's 'N' friction factor = 0.013 ----------------------------------------------------------------- Sub-Channel flow = 9.301(CFS) ' ' flow top width = 1.783(Ft.) ' ' velocity= 14.625(Ft/s) ' ' area = 0.636(Sq.Ft) ' ' Froude number = 4.315 Upstream point elevation = 1203.000(Ft.) Downstream point elevation = 1176.000(Ft.) Flow length = 300.000(Ft.) Travel time = 0.34 min. Time of concentration = 7.19 min. Depth of flow = 0.713(Ft.) Average velocity = 14.624(Ft/s) HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 11 - Total irregular channel flow = 9.301(CFS) Irregular channel normal depth above invert elev. = 0.713(Ft.) Average velocity of channel(s) = 14.624(Ft/s) Adding area flow to channel UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.883 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 4.177(In/Hr) for a 100.0 year storm Subarea runoff = 8.453(CFS) for 2.291(Ac.) Total runoff = 13.481(CFS) Total area = 3.543(Ac.) Depth of flow = 0.820(Ft.), Average velocity = 16.046(Ft/s) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.110 to Point/Station 1.103 **** CONFLUENCE OF MAIN STREAMS **** ______________________________________________________________________ The following data inside Main Stream is listed: In Main Stream number: 1 Stream flow area = 3.543(Ac.) Runoff from this stream = 13.481(CFS) Time of concentration = 7.19 min. Rainfall intensity = 4.177(In/Hr) Program is now starting with Main Stream No. 2 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.710 to Point/Station 1.720 **** INITIAL AREA EVALUATION **** ______________________________________________________________________ Initial area flow distance = 100.000(Ft.) Top (of initial area) elevation = 1230.000(Ft.) Bottom (of initial area) elevation = 1219.500(Ft.) Difference in elevation = 10.500(Ft.) Slope = 0.10500 s(percent)= 10.50 TC = k(0.480)*[(length^3)/(elevation change)]^0.2 Warning: TC computed to be less than 5 min.; program is assuming the time of concentration is 5 minutes. Initial area time of concentration = 5.000 min. Rainfall intensity = 5.099(In/Hr) for a 100.0 year storm SINGLE FAMILY (1 Acre Lot) Runoff Coefficient = 0.867 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 84.40 Pervious area fraction = 0.800; Impervious fraction = 0.200 Initial subarea runoff = 1.335(CFS) Total initial stream area = 0.302(Ac.) Pervious area fraction = 0.800 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 12 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.720 to Point/Station 1.730 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Depth of flow = 0.052(Ft.), Average velocity = 1.308(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 0.50 2 0.50 0.00 3 20.00 0.00 4 20.50 0.50 Manning's 'N' friction factor = 0.025 ----------------------------------------------------------------- Sub-Channel flow = 1.335(CFS) ' ' flow top width = 19.604(Ft.) ' ' velocity= 1.308(Ft/s) ' ' area = 1.020(Sq.Ft) ' ' Froude number = 1.011 Upstream point elevation = 1219.500(Ft.) Downstream point elevation = 1219.000(Ft.) Flow length = 20.000(Ft.) Travel time = 0.25 min. Time of concentration = 5.25 min. Depth of flow = 0.052(Ft.) Average velocity = 1.308(Ft/s) Total irregular channel flow = 1.335(CFS) Irregular channel normal depth above invert elev. = 0.052(Ft.) Average velocity of channel(s) = 1.308(Ft/s) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.730 to Point/Station 1.810 **** PIPEFLOW TRAVEL TIME (User specified size) **** ______________________________________________________________________ Upstream point/station elevation = 1217.500(Ft.) Downstream point/station elevation = 1205.000(Ft.) Pipe length = 40.00(Ft.) Manning's N = 0.013 No. of pipes = 1 Required pipe flow = 1.335(CFS) Given pipe size = 6.00(In.) Calculated individual pipe flow = 1.335(CFS) Normal flow depth in pipe = 2.73(In.) Flow top width inside pipe = 5.98(In.) Critical depth could not be calculated. Pipe flow velocity = 15.33(Ft/s) Travel time through pipe = 0.04 min. Time of concentration (TC) = 5.30 min. HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 13 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.810 to Point/Station 1.102 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Estimated mean flow rate at midpoint of channel = 1.607(CFS) Depth of flow = 0.305(Ft.), Average velocity = 6.898(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 1.00 2 1.50 0.00 3 5.00 1.00 4 6.00 1.20 Manning's 'N' friction factor = 0.013 ----------------------------------------------------------------- Sub-Channel flow = 1.607(CFS) ' ' flow top width = 1.526(Ft.) ' ' velocity= 6.898(Ft/s) ' ' area = 0.233(Sq.Ft) ' ' Froude number = 3.112 Upstream point elevation = 1205.000(Ft.) Downstream point elevation = 1199.000(Ft.) Flow length = 120.000(Ft.) Travel time = 0.29 min. Time of concentration = 5.59 min. Depth of flow = 0.305(Ft.) Average velocity = 6.898(Ft/s) Total irregular channel flow = 1.607(CFS) Irregular channel normal depth above invert elev. = 0.305(Ft.) Average velocity of channel(s) = 6.898(Ft/s) Adding area flow to channel UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.885 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 4.797(In/Hr) for a 100.0 year storm Subarea runoff = 0.522(CFS) for 0.123(Ac.) Total runoff = 1.857(CFS) Total area = 0.425(Ac.) Depth of flow = 0.322(Ft.), Average velocity = 7.152(Ft/s) HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 14 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.710 to Point/Station 1.102 **** CONFLUENCE OF MINOR STREAMS **** ______________________________________________________________________ Along Main Stream number: 2 in normal stream number 1 Stream flow area = 0.425(Ac.) Runoff from this stream = 1.857(CFS) Time of concentration = 5.59 min. Rainfall intensity = 4.797(In/Hr) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.910 to Point/Station 1.920 **** INITIAL AREA EVALUATION **** ______________________________________________________________________ Initial area flow distance = 80.000(Ft.) Top (of initial area) elevation = 1219.900(Ft.) Bottom (of initial area) elevation = 1219.100(Ft.) Difference in elevation = 0.800(Ft.) Slope = 0.01000 s(percent)= 1.00 TC = k(0.480)*[(length^3)/(elevation change)]^0.2 Initial area time of concentration = 6.958 min. Rainfall intensity = 4.252(In/Hr) for a 100.0 year storm SINGLE FAMILY (1 Acre Lot) Runoff Coefficient = 0.861 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 84.40 Pervious area fraction = 0.800; Impervious fraction = 0.200 Initial subarea runoff = 0.355(CFS) Total initial stream area = 0.097(Ac.) Pervious area fraction = 0.800 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.920 to Point/Station 1.101 **** PIPEFLOW TRAVEL TIME (User specified size) **** ______________________________________________________________________ Upstream point/station elevation = 1217.600(Ft.) Downstream point/station elevation = 1205.000(Ft.) Pipe length = 40.00(Ft.) Manning's N = 0.013 No. of pipes = 1 Required pipe flow = 0.355(CFS) Given pipe size = 6.00(In.) Calculated individual pipe flow = 0.355(CFS) Normal flow depth in pipe = 1.36(In.) Flow top width inside pipe = 5.02(In.) Critical Depth = 3.63(In.) Pipe flow velocity = 10.61(Ft/s) Travel time through pipe = 0.06 min. Time of concentration (TC) = 7.02 min. HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 15 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.101 to Point/Station 1.102 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Estimated mean flow rate at midpoint of channel = 0.525(CFS) Depth of flow = 0.199(Ft.), Average velocity = 5.299(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 1.00 2 1.50 0.00 3 5.00 1.00 4 6.00 1.20 Manning's 'N' friction factor = 0.013 ----------------------------------------------------------------- Sub-Channel flow = 0.525(CFS) ' ' flow top width = 0.995(Ft.) ' ' velocity= 5.299(Ft/s) ' ' area = 0.099(Sq.Ft) ' ' Froude number = 2.960 Upstream point elevation = 1205.000(Ft.) Downstream point elevation = 1199.000(Ft.) Flow length = 115.000(Ft.) Travel time = 0.36 min. Time of concentration = 7.38 min. Depth of flow = 0.199(Ft.) Average velocity = 5.299(Ft/s) Total irregular channel flow = 0.525(CFS) Irregular channel normal depth above invert elev. = 0.199(Ft.) Average velocity of channel(s) = 5.299(Ft/s) Adding area flow to channel UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.883 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 4.115(In/Hr) for a 100.0 year storm Subarea runoff = 0.338(CFS) for 0.093(Ac.) Total runoff = 0.693(CFS) Total area = 0.190(Ac.) Depth of flow = 0.221(Ft.), Average velocity = 5.680(Ft/s) HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 16 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.910 to Point/Station 1.102 **** CONFLUENCE OF MINOR STREAMS **** ______________________________________________________________________ Along Main Stream number: 2 in normal stream number 2 Stream flow area = 0.190(Ac.) Runoff from this stream = 0.693(CFS) Time of concentration = 7.38 min. Rainfall intensity = 4.115(In/Hr) Summary of stream data: Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr) 1 1.857 5.59 4.797 2 0.693 7.38 4.115 Largest stream flow has longer or shorter time of concentration Qp = 1.857 + sum of Qa Tb/Ta 0.693 * 0.757 = 0.524 Qp = 2.382 Total of 2 streams to confluence: Flow rates before confluence point: 1.857 0.693 Area of streams before confluence: 0.425 0.190 Results of confluence: Total flow rate = 2.382(CFS) Time of concentration = 5.588 min. Effective stream area after confluence = 0.615(Ac.) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.102 to Point/Station 1.103 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Depth of flow = 0.297(Ft.), Average velocity = 18.012(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 1.00 2 1.50 0.00 3 3.00 1.00 Manning's 'N' friction factor = 0.013 ----------------------------------------------------------------- Sub-Channel flow = 2.382(CFS) ' ' flow top width = 0.891(Ft.) ' ' velocity= 18.012(Ft/s) ' ' area = 0.132(Sq.Ft) ' ' Froude number = 8.238 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 17 - Upstream point elevation = 1199.000(Ft.) Downstream point elevation = 1176.800(Ft.) Flow length = 55.000(Ft.) Travel time = 0.05 min. Time of concentration = 5.64 min. Depth of flow = 0.297(Ft.) Average velocity = 18.012(Ft/s) Total irregular channel flow = 2.382(CFS) Irregular channel normal depth above invert elev. = 0.297(Ft.) Average velocity of channel(s) = 18.012(Ft/s) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.710 to Point/Station 1.103 **** CONFLUENCE OF MAIN STREAMS **** ______________________________________________________________________ The following data inside Main Stream is listed: In Main Stream number: 2 Stream flow area = 0.615(Ac.) Runoff from this stream = 2.382(CFS) Time of concentration = 5.64 min. Rainfall intensity = 4.773(In/Hr) Summary of stream data: Stream Flow rate TC Rainfall Intensity No. (CFS) (min) (In/Hr) 1 13.481 7.19 4.177 2 2.382 5.64 4.773 Largest stream flow has longer time of concentration Qp = 13.481 + sum of Qb Ia/Ib 2.382 * 0.875 = 2.085 Qp = 15.565 Total of 2 main streams to confluence: Flow rates before confluence point: 13.481 2.382 Area of streams before confluence: 3.543 0.615 Results of confluence: Total flow rate = 15.565(CFS) Time of concentration = 7.185 min. Effective stream area after confluence = 4.158(Ac.) HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 18 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.103 to Point/Station 1.111 **** IMPROVED CHANNEL TRAVEL TIME **** ______________________________________________________________________ Upstream point elevation = 1176.800(Ft.) Downstream point elevation = 1176.500(Ft.) Channel length thru subarea = 6.000(Ft.) Channel base width = 2.500(Ft.) Slope or 'Z' of left channel bank = 3.000 Slope or 'Z' of right channel bank = 3.000 Manning's 'N' = 0.044 Maximum depth of channel = 1.000(Ft.) Flow(q) thru subarea = 15.565(CFS) Depth of flow = 0.723(Ft.), Average velocity = 4.612(Ft/s) Channel flow top width = 6.837(Ft.) Flow Velocity = 4.61(Ft/s) Travel time = 0.02 min. Time of concentration = 7.21 min. Sub-Channel No. 1 Critical depth = 0.781(Ft.) ' ' ' Critical flow top width = 7.188(Ft.) ' ' ' Critical flow velocity= 4.113(Ft/s) ' ' ' Critical flow area = 3.784(Sq.Ft) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 1.111 to Point/Station 1.112 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Estimated mean flow rate at midpoint of channel = 16.335(CFS) Depth of flow = 0.746(Ft.), Average velocity = 4.807(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 1.00 2 5.30 0.50 3 7.80 0.00 4 9.30 0.50 5 27.30 1.00 Manning's 'N' friction factor = 0.025 ----------------------------------------------------------------- Sub-Channel flow = 16.335(CFS) ' ' flow top width = 15.475(Ft.) ' ' velocity= 4.807(Ft/s) ' ' area = 3.398(Sq.Ft) ' ' Froude number = 1.808 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 19 - Upstream point elevation = 1176.500(Ft.) Downstream point elevation = 1173.000(Ft.) Flow length = 70.000(Ft.) Travel time = 0.24 min. Time of concentration = 7.45 min. Depth of flow = 0.746(Ft.) Average velocity = 4.807(Ft/s) Total irregular channel flow = 16.335(CFS) Irregular channel normal depth above invert elev. = 0.746(Ft.) Average velocity of channel(s) = 4.807(Ft/s) Adding area flow to channel UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.883 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 4.095(In/Hr) for a 100.0 year storm Subarea runoff = 1.486(CFS) for 0.411(Ac.) Total runoff = 17.051(CFS) Total area = 4.569(Ac.) Depth of flow = 0.754(Ft.), Average velocity = 4.846(Ft/s) End of computations, total study area = 4.57 (Ac.) The following figures may be used for a unit hydrograph study of the same area. Area averaged pervious area fraction(Ap) = 0.962 Area averaged RI index number = 82.8 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 20 - PROPOSED CONDITIONS – CONFLUENCE POINT B 100 YEAR DESIGN STORM EVENT Riverside County Rational Hydrology Program CIVILCADD/CIVILDESIGN Engineering Software,(c) 1989 - 2014 Version 9.0 Rational Hydrology Study Date: 09/13/20 File:mcgovernprb2d3.out ------------------------------------------------------------------------ ********* Hydrology Study Control Information ********** English (in-lb) Units used in input data file ------------------------------------------------------------------------ Rational Method Hydrology Program based on Riverside County Flood Control & Water Conservation District 1978 hydrology manual Storm event (year) = 100.00 Antecedent Moisture Condition = 3 Standard intensity-duration curves data (Plate D-4.1) For the [ Murrieta,Tmc,Rnch CaNorco ] area used. 10 year storm 10 minute intensity = 2.360(In/Hr) 10 year storm 60 minute intensity = 0.880(In/Hr) 100 year storm 10 minute intensity = 3.480(In/Hr) 100 year storm 60 minute intensity = 1.300(In/Hr) Storm event year = 100.0 Calculated rainfall intensity data: 1 hour intensity = 1.300(In/Hr) Slope of intensity duration curve = 0.5500 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 2.110 to Point/Station 2.210 **** INITIAL AREA EVALUATION **** ______________________________________________________________________ Initial area flow distance = 100.000(Ft.) Top (of initial area) elevation = 1221.700(Ft.) Bottom (of initial area) elevation = 1184.000(Ft.) Difference in elevation = 37.700(Ft.) Slope = 0.37700 s(percent)= 37.70 TC = k(0.530)*[(length^3)/(elevation change)]^0.2 Warning: TC computed to be less than 5 min.; program is assuming the time of concentration is 5 minutes. Initial area time of concentration = 5.000 min. Rainfall intensity = 5.099(In/Hr) for a 100.0 year storm UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.886 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Initial subarea runoff = 0.732(CFS) Total initial stream area = 0.162(Ac.) Pervious area fraction = 1.000 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 21 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 2.210 to Point/Station 2.220 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Estimated mean flow rate at midpoint of channel = 1.017(CFS) Depth of flow = 0.162(Ft.), Average velocity = 5.860(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 1.00 2 4.40 0.50 3 7.70 0.00 4 11.00 0.50 5 14.20 1.00 Manning's 'N' friction factor = 0.020 ----------------------------------------------------------------- Sub-Channel flow = 1.017(CFS) ' ' flow top width = 2.140(Ft.) ' ' velocity= 5.860(Ft/s) ' ' area = 0.174(Sq.Ft) ' ' Froude number = 3.627 Upstream point elevation = 1184.000(Ft.) Downstream point elevation = 1175.000(Ft.) Flow length = 50.000(Ft.) Travel time = 0.14 min. Time of concentration = 5.14 min. Depth of flow = 0.162(Ft.) Average velocity = 5.860(Ft/s) Total irregular channel flow = 1.017(CFS) Irregular channel normal depth above invert elev. = 0.162(Ft.) Average velocity of channel(s) = 5.860(Ft/s) Adding area flow to channel UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.886 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 5.021(In/Hr) for a 100.0 year storm Subarea runoff = 0.561(CFS) for 0.126(Ac.) Total runoff = 1.293(CFS) Total area = 0.288(Ac.) Depth of flow = 0.177(Ft.), Average velocity = 6.223(Ft/s) End of computations, total study area = 0.29 (Ac.) The following figures may be used for a unit hydrograph study of the same area. Area averaged pervious area fraction(Ap) = 1.000 Area averaged RI index number = 86.0 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 22 - PROPOSED CONDITIONS – CONFLUENCE POINT C 100 YEAR DESIGN STORM EVENT Riverside County Rational Hydrology Program CIVILCADD/CIVILDESIGN Engineering Software,(c) 1989 - 2014 Version 9.0 Rational Hydrology Study Date: 09/13/20 File:mcgovernprb3d3.out ------------------------------------------------------------------------ ********* Hydrology Study Control Information ********** English (in-lb) Units used in input data file ------------------------------------------------------------------------ Rational Method Hydrology Program based on Riverside County Flood Control & Water Conservation District 1978 hydrology manual Storm event (year) = 100.00 Antecedent Moisture Condition = 3 Standard intensity-duration curves data (Plate D-4.1) For the [ Murrieta,Tmc,Rnch CaNorco ] area used. 10 year storm 10 minute intensity = 2.360(In/Hr) 10 year storm 60 minute intensity = 0.880(In/Hr) 100 year storm 10 minute intensity = 3.480(In/Hr) 100 year storm 60 minute intensity = 1.300(In/Hr) Storm event year = 100.0 Calculated rainfall intensity data: 1 hour intensity = 1.300(In/Hr) Slope of intensity duration curve = 0.5500 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 3.110 to Point/Station 3.120 **** INITIAL AREA EVALUATION **** ______________________________________________________________________ Initial area flow distance = 100.000(Ft.) Top (of initial area) elevation = 1221.330(Ft.) Bottom (of initial area) elevation = 1220.500(Ft.) Difference in elevation = 0.830(Ft.) Slope = 0.00830 s(percent)= 0.83 TC = k(0.480)*[(length^3)/(elevation change)]^0.2 Initial area time of concentration = 7.896 min. Rainfall intensity = 3.966(In/Hr) for a 100.0 year storm SINGLE FAMILY (1 Acre Lot) Runoff Coefficient = 0.858 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 84.40 Pervious area fraction = 0.800; Impervious fraction = 0.200 Initial subarea runoff = 1.262(CFS) Total initial stream area = 0.371(Ac.) Pervious area fraction = 0.800 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 23 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 3.120 to Point/Station 3.130 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Depth of flow = 0.178(Ft.), Average velocity = 1.882(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 1.00 2 5.00 0.00 3 20.00 0.40 Manning's 'N' friction factor = 0.020 ----------------------------------------------------------------- Sub-Channel flow = 1.262(CFS) ' ' flow top width = 7.550(Ft.) ' ' velocity= 1.882(Ft/s) ' ' area = 0.671(Sq.Ft) ' ' Froude number = 1.113 Upstream point elevation = 1220.500(Ft.) Downstream point elevation = 1219.200(Ft.) Flow length = 80.000(Ft.) Travel time = 0.71 min. Time of concentration = 8.60 min. Depth of flow = 0.178(Ft.) Average velocity = 1.882(Ft/s) Total irregular channel flow = 1.262(CFS) Irregular channel normal depth above invert elev. = 0.178(Ft.) Average velocity of channel(s) = 1.882(Ft/s) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 3.130 to Point/Station 3.140 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Depth of flow = 0.082(Ft.), Average velocity = 0.788(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 0.50 2 0.50 0.00 3 20.00 0.00 4 20.50 0.50 Manning's 'N' friction factor = 0.025 ----------------------------------------------------------------- Sub-Channel flow = 1.262(CFS) ' ' flow top width = 19.664(Ft.) ' ' velocity= 0.788(Ft/s) ' ' area = 1.602(Sq.Ft) ' ' Froude number = 0.487 Upstream point elevation = 1219.200(Ft.) Downstream point elevation = 1219.100(Ft.) HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 24 - Flow length = 20.000(Ft.) Travel time = 0.42 min. Time of concentration = 9.03 min. Depth of flow = 0.082(Ft.) Average velocity = 0.788(Ft/s) Total irregular channel flow = 1.262(CFS) Irregular channel normal depth above invert elev. = 0.082(Ft.) Average velocity of channel(s) = 0.788(Ft/s) ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 3.140 to Point/Station 3.150 **** PIPEFLOW TRAVEL TIME (User specified size) **** ______________________________________________________________________ Upstream point/station elevation = 1218.080(Ft.) Downstream point/station elevation = 1218.000(Ft.) Pipe length = 10.00(Ft.) Manning's N = 0.013 No. of pipes = 1 Required pipe flow = 1.262(CFS) Given pipe size = 12.00(In.) Calculated individual pipe flow = 1.262(CFS) Normal flow depth in pipe = 5.25(In.) Flow top width inside pipe = 11.91(In.) Critical Depth = 5.69(In.) Pipe flow velocity = 3.82(Ft/s) Travel time through pipe = 0.04 min. Time of concentration (TC) = 9.07 min. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 3.150 to Point/Station 3.210 **** IMPROVED CHANNEL TRAVEL TIME **** ______________________________________________________________________ Upstream point elevation = 1218.000(Ft.) Downstream point elevation = 1217.000(Ft.) Channel length thru subarea = 6.000(Ft.) Channel base width = 2.500(Ft.) Slope or 'Z' of left channel bank = 3.000 Slope or 'Z' of right channel bank = 3.000 Manning's 'N' = 0.037 Maximum depth of channel = 1.000(Ft.) Flow(q) thru subarea = 1.262(CFS) Depth of flow = 0.120(Ft.), Average velocity = 3.664(Ft/s) Channel flow top width = 3.222(Ft.) Flow Velocity = 3.66(Ft/s) Travel time = 0.03 min. Time of concentration = 9.10 min. Sub-Channel No. 1 Critical depth = 0.184(Ft.) ' ' ' Critical flow top width = 3.602(Ft.) ' ' ' Critical flow velocity= 2.254(Ft/s) ' ' ' Critical flow area = 0.560(Sq.Ft) HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 Attachment 3 - 25 - ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Process from Point/Station 3.210 to Point/Station 3.220 **** IRREGULAR CHANNEL FLOW TRAVEL TIME **** ______________________________________________________________________ Estimated mean flow rate at midpoint of channel = 1.477(CFS) Depth of flow = 0.187(Ft.), Average velocity = 7.839(Ft/s) ******* Irregular Channel Data *********** ----------------------------------------------------------------- Information entered for subchannel number 1 : Point number 'X' coordinate 'Y' coordinate 1 0.00 1.00 2 5.60 0.25 3 6.80 0.00 4 8.30 0.25 5 12.30 1.00 Manning's 'N' friction factor = 0.020 ----------------------------------------------------------------- Sub-Channel flow = 1.477(CFS) ' ' flow top width = 2.017(Ft.) ' ' velocity= 7.839(Ft/s) ' ' area = 0.188(Sq.Ft) ' ' Froude number = 4.520 Upstream point elevation = 1217.000(Ft.) Downstream point elevation = 1174.000(Ft.) Flow length = 160.000(Ft.) Travel time = 0.34 min. Time of concentration = 9.44 min. Depth of flow = 0.187(Ft.) Average velocity = 7.839(Ft/s) Total irregular channel flow = 1.477(CFS) Irregular channel normal depth above invert elev. = 0.187(Ft.) Average velocity of channel(s) = 7.839(Ft/s) Adding area flow to channel UNDEVELOPED (poor cover) subarea Runoff Coefficient = 0.881 Decimal fraction soil group A = 0.000 Decimal fraction soil group B = 0.000 Decimal fraction soil group C = 1.000 Decimal fraction soil group D = 0.000 RI index for soil(AMC 3) = 94.40 Pervious area fraction = 1.000; Impervious fraction = 0.000 Rainfall intensity = 3.595(In/Hr) for a 100.0 year storm Subarea runoff = 0.399(CFS) for 0.126(Ac.) Total runoff = 1.661(CFS) Total area = 0.497(Ac.) Depth of flow = 0.195(Ft.), Average velocity = 8.073(Ft/s) End of computations, total study area = 0.50 (Ac.) The following figures may be used for a unit hydrograph study of the same area. Area averaged pervious area fraction(Ap) = 0.851 Area averaged RI index number = 73.3 HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 ATTACHMENT 4: EXHIBITS This attachment contains the vicinity map, the existing condition exhibit, and the proposed condition exhibits. Please see the attached exhibits. A B SHO W A L T E R R O A D SH O W A L T E R R O A D 945-070-004 945-070-003 945-080-025 945-070-020 945-070-009 945-070-015 945-070-009 945-070-001 945-070-004 C HYDROLOGY REPORT MC GOVERN RESIDENCE LD19-3729 SHOWALTER ROAD, TEMECULA, CA 92592 ATTACHMENT 5: FEMA ANALYSIS This attachment contains the data used in the FEMA determination. USGS The National Map: Orthoimagery. Data refreshed April 2020 National Flood Hazard Layer FIRMette 0 500 1,000 1,500 2,000250 Feet Ü SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT SPECIAL FLOOD HAZARD AREAS Without Base Flood Elevation (BFE) Zone A, V, A99 With BFE or DepthZone AE, AO, AH, VE, AR Regulatory Floodway 0.2% Annual Chance Flood Hazard, Areas of 1% annual chance flood with average depth less than one foot or with drainage areas of less than one square mileZone X Future Conditions 1% Annual Chance Flood HazardZone X Area with Reduced Flood Risk due to Levee. See Notes.Zone X Area with Flood Risk due to LeveeZone D NO SCREEN Area of Minimal Flood Hazard Zone X Area of Undetermined Flood HazardZone D Channel, Culvert, or Storm Sewer Levee, Dike, or Floodwall Cross Sections with 1% Annual Chance 17.5 Water Surface Elevation Coastal Transect Coastal Transect Baseline Profile Baseline Hydrographic Feature Base Flood Elevation Line (BFE) Effective LOMRs Limit of Study Jurisdiction Boundary Digital Data Available No Digital Data Available Unmapped This map complies with FEMA's standards for the use of digital flood maps if it is not void as described below. The basemap shown complies with FEMA's basemap accuracy standards The flood hazard information is derived directly from the authoritative NFHL web services provided by FEMA. This map was exported on 7/11/2020 at 12:08 AM and does not reflect changes or amendments subsequent to this date and time. The NFHL and effective information may change or become superseded by new data over time. This map image is void if the one or more of the following map elements do not appear: basemap imagery, flood zone labels, legend, scale bar, map creation date, community identifiers, FIRM panel number, and FIRM effective date. Map images for unmapped and unmodernized areas cannot be used for regulatory purposes. Legend OTHER AREAS OF FLOOD HAZARD OTHER AREAS GENERAL STRUCTURES OTHER FEATURES MAP PANELS 8 B 20.2 The pin displayed on the map is an approximate point selected by the user and does not represent an authoritative property location. 1:6,000 117°7'59"W 33°30'2"N 117°7'21"W 33°29'32"N APPROXIMATE SITE ZONE X 38 PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS Preparation Date: September 14, 2020 Template Date: September 26, 2019 ATTACHMENT 7 Copy of Project's Geotechnical and Groundwater Investigation Report ☒ This attachment is empty because a geotechnical and groundwater report is not required. If hardcopy or CD is not attached, the following information should be provided: Title: NRCS Soils Report Prepared By: NRCS Date: March 2020 The geotechnical and groundwater investigation report must address the following key elements, and where appropriate, mitigation recommendations must be provided.  Identify areas of the project site where infiltration is likely to be feasible and provide justifications for selection of those areas based on soil types, slopes, proximity to existing features, etc. Include completed and signed Worksheet C.4-1 (see Appendix I).  Investigate, evaluate and estimate the vertical infiltration rates and capacities in accordance with the guidance provided in Appendix D which describes infiltration testing and appropriate factor of safety to be applied for infiltration testing results. The site may be broken into sub-basins, each of which has different infiltration rates or capacities.  Describe the infiltration/ percolation test results and correlation with published infiltration/ percolation rates based on soil parameters or classification. Recommend providing design infiltration/percolation rate(s) at the sub-basins. Use Worksheet D.5-1 (see Appendix I).  Investigate the subsurface geological conditions and geotechnical conditions that would affect infiltration or migration of water toward structures, slopes, utilities, or other features. Describe the anticipated flow path of infiltrated water. Indicate if the water will flow into pavement sections, utility trench bedding, wall drains, foundation drains, or other permeable improvements.  Investigate depth to groundwater and the nature of the groundwater. Include an estimate of the high seasonal groundwater elevations.  Evaluate proposed use of the site (industrial use, residential use, etc.), soil and groundwater data and provide a concluding opinion whether proposed storm water infiltration could cause adverse impacts to groundwater quality and if it does cause impacts whether the impacts could be reasonably mitigated or not.  Estimate the maximum allowable infiltration rates and volumes that could occur at the site that would avoid damage to existing and proposed structures, utilities, slopes, or other features. In addition the report must indicate if the recommended infiltration rate is appropriate based on the conditions exposed during construction.  Provide a concluding opinion regarding whether or not the proposed onsite storm water infiltration/percolation BMP will result in soil piping, daylight water seepage, slope instability, or ground settlement. PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS 39 Template Date: September 26, 2019 Preparation Date: September 14, 2020  Recommend measures to substantially mitigate or avoid any potentially detrimental effects of the storm water infiltration BMPs or associated soil response on existing or proposed improvements or structures, utilities, slopes or other features within and adjacent to the site. For example, minimize soil compaction.  Provide guidance for the selection and location of infiltration BMPs, including the minimum separations between such infiltration BMPs and structures, streets, utilities, manufactured and existing slopes, engineered fills, utilities or other features. Include guidance for measures that could be used to reduce the minimum separations or to mitigate the potential impacts of infiltration BMPs. 40 PRIORITY DEVELOPMENT PROJECT (PDP) REQUIREMENTS Preparation Date: September 14, 2020 Template Date: September 26, 2019 This page was left intentionally blank. United States Department of Agriculture A product of the National Cooperative Soil Survey, a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local participants Custom Soil Resource Report for Western Riverside Area, California McGovern Residence Natural Resources Conservation Service March 12, 2020 Preface Soil surveys contain information that affects land use planning in survey areas. They highlight soil limitations that affect various land uses and provide information about the properties of the soils in the survey areas. Soil surveys are designed for many different users, including farmers, ranchers, foresters, agronomists, urban planners, community officials, engineers, developers, builders, and home buyers. Also, conservationists, teachers, students, and specialists in recreation, waste disposal, and pollution control can use the surveys to help them understand, protect, or enhance the environment. Various land use regulations of Federal, State, and local governments may impose special restrictions on land use or land treatment. Soil surveys identify soil properties that are used in making various land use or land treatment decisions. The information is intended to help the land users identify and reduce the effects of soil limitations on various land uses. The landowner or user is responsible for identifying and complying with existing laws and regulations. Although soil survey information can be used for general farm, local, and wider area planning, onsite investigation is needed to supplement this information in some cases. Examples include soil quality assessments (http://www.nrcs.usda.gov/wps/ portal/nrcs/main/soils/health/) and certain conservation and engineering applications. For more detailed information, contact your local USDA Service Center (https://offices.sc.egov.usda.gov/locator/app?agency=nrcs) or your NRCS State Soil Scientist (http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/contactus/? cid=nrcs142p2_053951). Great differences in soil properties can occur within short distances. Some soils are seasonally wet or subject to flooding. Some are too unstable to be used as a foundation for buildings or roads. Clayey or wet soils are poorly suited to use as septic tank absorption fields. A high water table makes a soil poorly suited to basements or underground installations. The National Cooperative Soil Survey is a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local agencies. The Natural Resources Conservation Service (NRCS) has leadership for the Federal part of the National Cooperative Soil Survey. Information about soils is updated periodically. Updated information is available through the NRCS Web Soil Survey, the site for official soil survey information. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or a part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require 2 alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer. 3 Contents Preface....................................................................................................................2 How Soil Surveys Are Made..................................................................................5 Soil Map..................................................................................................................8 Soil Map................................................................................................................9 Legend................................................................................................................10 Map Unit Legend................................................................................................11 Map Unit Descriptions.........................................................................................11 Western Riverside Area, California.................................................................13 GzG—Gullied land......................................................................................13 RmE3—Ramona and Buren sandy loams, 15 to 25 percent slopes, severely eroded....................................................................................13 References............................................................................................................16 4 How Soil Surveys Are Made Soil surveys are made to provide information about the soils and miscellaneous areas in a specific area. They include a description of the soils and miscellaneous areas and their location on the landscape and tables that show soil properties and limitations affecting various uses. Soil scientists observed the steepness, length, and shape of the slopes; the general pattern of drainage; the kinds of crops and native plants; and the kinds of bedrock. They observed and described many soil profiles. A soil profile is the sequence of natural layers, or horizons, in a soil. The profile extends from the surface down into the unconsolidated material in which the soil formed or from the surface down to bedrock. The unconsolidated material is devoid of roots and other living organisms and has not been changed by other biological activity. Currently, soils are mapped according to the boundaries of major land resource areas (MLRAs). MLRAs are geographically associated land resource units that share common characteristics related to physiography, geology, climate, water resources, soils, biological resources, and land uses (USDA, 2006). Soil survey areas typically consist of parts of one or more MLRA. The soils and miscellaneous areas in a survey area occur in an orderly pattern that is related to the geology, landforms, relief, climate, and natural vegetation of the area. Each kind of soil and miscellaneous area is associated with a particular kind of landform or with a segment of the landform. By observing the soils and miscellaneous areas in the survey area and relating their position to specific segments of the landform, a soil scientist develops a concept, or model, of how they were formed. Thus, during mapping, this model enables the soil scientist to predict with a considerable degree of accuracy the kind of soil or miscellaneous area at a specific location on the landscape. Commonly, individual soils on the landscape merge into one another as their characteristics gradually change. To construct an accurate soil map, however, soil scientists must determine the boundaries between the soils. They can observe only a limited number of soil profiles. Nevertheless, these observations, supplemented by an understanding of the soil-vegetation-landscape relationship, are sufficient to verify predictions of the kinds of soil in an area and to determine the boundaries. Soil scientists recorded the characteristics of the soil profiles that they studied. They noted soil color, texture, size and shape of soil aggregates, kind and amount of rock fragments, distribution of plant roots, reaction, and other features that enable them to identify soils. After describing the soils in the survey area and determining their properties, the soil scientists assigned the soils to taxonomic classes (units). Taxonomic classes are concepts. Each taxonomic class has a set of soil characteristics with precisely defined limits. The classes are used as a basis for comparison to classify soils systematically. Soil taxonomy, the system of taxonomic classification used in the United States, is based mainly on the kind and character of soil properties and the arrangement of horizons within the profile. After the soil 5 scientists classified and named the soils in the survey area, they compared the individual soils with similar soils in the same taxonomic class in other areas so that they could confirm data and assemble additional data based on experience and research. The objective of soil mapping is not to delineate pure map unit components; the objective is to separate the landscape into landforms or landform segments that have similar use and management requirements. Each map unit is defined by a unique combination of soil components and/or miscellaneous areas in predictable proportions. Some components may be highly contrasting to the other components of the map unit. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The delineation of such landforms and landform segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, onsite investigation is needed to define and locate the soils and miscellaneous areas. Soil scientists make many field observations in the process of producing a soil map. The frequency of observation is dependent upon several factors, including scale of mapping, intensity of mapping, design of map units, complexity of the landscape, and experience of the soil scientist. Observations are made to test and refine the soil-landscape model and predictions and to verify the classification of the soils at specific locations. Once the soil-landscape model is refined, a significantly smaller number of measurements of individual soil properties are made and recorded. These measurements may include field measurements, such as those for color, depth to bedrock, and texture, and laboratory measurements, such as those for content of sand, silt, clay, salt, and other components. Properties of each soil typically vary from one point to another across the landscape. Observations for map unit components are aggregated to develop ranges of characteristics for the components. The aggregated values are presented. Direct measurements do not exist for every property presented for every map unit component. Values for some properties are estimated from combinations of other properties. While a soil survey is in progress, samples of some of the soils in the area generally are collected for laboratory analyses and for engineering tests. Soil scientists interpret the data from these analyses and tests as well as the field-observed characteristics and the soil properties to determine the expected behavior of the soils under different uses. Interpretations for all of the soils are field tested through observation of the soils in different uses and under different levels of management. Some interpretations are modified to fit local conditions, and some new interpretations are developed to meet local needs. Data are assembled from other sources, such as research information, production records, and field experience of specialists. For example, data on crop yields under defined levels of management are assembled from farm records and from field or plot experiments on the same kinds of soil. Predictions about soil behavior are based not only on soil properties but also on such variables as climate and biological activity. Soil conditions are predictable over long periods of time, but they are not predictable from year to year. For example, soil scientists can predict with a fairly high degree of accuracy that a given soil will have a high water table within certain depths in most years, but they cannot predict that a high water table will always be at a specific level in the soil on a specific date. After soil scientists located and identified the significant natural bodies of soil in the survey area, they drew the boundaries of these bodies on aerial photographs and Custom Soil Resource Report 6 identified each as a specific map unit. Aerial photographs show trees, buildings, fields, roads, and rivers, all of which help in locating boundaries accurately. Custom Soil Resource Report 7 Soil Map The soil map section includes the soil map for the defined area of interest, a list of soil map units on the map and extent of each map unit, and cartographic symbols displayed on the map. Also presented are various metadata about data used to produce the map, and a description of each soil map unit. 8 9 Custom Soil Resource Report Soil Map 37 0 6 1 1 0 37 0 6 1 4 0 37 0 6 1 7 0 37 0 6 2 0 0 37 0 6 2 3 0 37 0 6 2 6 0 37 0 6 2 9 0 37 0 6 3 2 0 37 0 6 3 5 0 37 0 6 0 8 0 37 0 6 1 1 0 37 0 6 1 4 0 37 0 6 1 7 0 37 0 6 2 0 0 37 0 6 2 3 0 37 0 6 2 6 0 37 0 6 2 9 0 37 0 6 3 2 0 37 0 6 3 5 0 488060 488090 488120 488150 488180 488210 488240 488060 488090 488120 488150 488180 488210 488240 33° 29' 47'' N 11 7 ° 7 ' 4 3 ' ' W 33° 29' 47'' N 11 7 ° 7 ' 3 5 ' ' W 33° 29' 39'' N 11 7 ° 7 ' 4 3 ' ' W 33° 29' 39'' N 11 7 ° 7 ' 3 5 ' ' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 11N WGS84 0 50 100 200 300 Feet 0 20 40 80 120 Meters Map Scale: 1:1,350 if printed on A portrait (8.5" x 11") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:15,800. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Western Riverside Area, California Survey Area Data: Version 12, Sep 16, 2019 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: May 15, 2018—Jun 25, 2018 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Custom Soil Resource Report 10 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI GzG Gullied land 2.0 82.1% RmE3 Ramona and Buren sandy loams, 15 to 25 percent slopes, severely eroded 0.4 17.9% Totals for Area of Interest 2.4 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, Custom Soil Resource Report 11 onsite investigation is needed to define and locate the soils and miscellaneous areas. An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps. The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha-Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha-Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. Custom Soil Resource Report 12 Western Riverside Area, California GzG—Gullied land Map Unit Composition Gullied land: 100 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Gullied Land Setting Landform: Terraces Landform position (two-dimensional): Backslope Landform position (three-dimensional): Riser Down-slope shape: Concave Across-slope shape: Concave Typical profile H1 - 0 to 60 inches: variable Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 8 Hydric soil rating: No RmE3—Ramona and Buren sandy loams, 15 to 25 percent slopes, severely eroded Map Unit Setting National map unit symbol: hcyj Elevation: 250 to 3,500 feet Mean annual precipitation: 10 to 20 inches Mean annual air temperature: 63 degrees F Frost-free period: 230 to 320 days Farmland classification: Not prime farmland Map Unit Composition Ramona and similar soils: 45 percent Buren and similar soils: 40 percent Minor components: 15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Ramona Setting Landform: Alluvial fans, terraces Landform position (three-dimensional): Tread Down-slope shape: Concave Across-slope shape: Convex Parent material: Alluvium derived from granite Typical profile H1 - 0 to 8 inches: sandy loam Custom Soil Resource Report 13 H2 - 8 to 17 inches: fine sandy loam H3 - 17 to 68 inches: sandy clay loam H4 - 68 to 74 inches: gravelly sandy loam Properties and qualities Slope: 15 to 25 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Well drained Runoff class: Very high Capacity of the most limiting layer to transmit water (Ksat): Moderately high (0.20 to 0.57 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Calcium carbonate, maximum in profile: 1 percent Available water storage in profile: Moderate (about 8.4 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 6e Hydrologic Soil Group: C Ecological site: LOAMY (1975) (R019XD029CA) Hydric soil rating: No Description of Buren Setting Landform: Alluvial fans, terraces Landform position (three-dimensional): Tread Down-slope shape: Linear Across-slope shape: Convex, linear Parent material: Alluvium Typical profile H1 - 0 to 12 inches: sandy loam H2 - 12 to 28 inches: loam H3 - 28 to 37 inches: loam H4 - 37 to 52 inches: cemented Properties and qualities Slope: 15 to 25 percent Depth to restrictive feature: 37 to 40 inches to duripan Natural drainage class: Well drained Runoff class: Very high Capacity of the most limiting layer to transmit water (Ksat): Very low to moderately low (0.00 to 0.06 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Calcium carbonate, maximum in profile: 1 percent Salinity, maximum in profile: Nonsaline to slightly saline (0.0 to 4.0 mmhos/cm) Available water storage in profile: Low (about 5.5 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 6e Hydrologic Soil Group: C Custom Soil Resource Report 14 Ecological site: LOAMY (1975) (R019XD029CA) Hydric soil rating: No Minor Components Ramona Percent of map unit: 5 percent Hydric soil rating: No Buren Percent of map unit: 5 percent Hydric soil rating: No Hanford Percent of map unit: 5 percent Hydric soil rating: No Custom Soil Resource Report 15 References American Association of State Highway and Transportation Officials (AASHTO). 2004. Standard specifications for transportation materials and methods of sampling and testing. 24th edition. American Society for Testing and Materials (ASTM). 2005. Standard classification of soils for engineering purposes. ASTM Standard D2487-00. Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deep-water habitats of the United States. U.S. Fish and Wildlife Service FWS/OBS-79/31. Federal Register. July 13, 1994. Changes in hydric soils of the United States. Federal Register. September 18, 2002. Hydric soils of the United States. Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric soils in the United States. National Research Council. 1995. Wetlands: Characteristics and boundaries. Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S. Department of Agriculture Handbook 18. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/national/soils/?cid=nrcs142p2_054262 Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service, U.S. Department of Agriculture Handbook 436. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053577 Soil Survey Staff. 2010. Keys to soil taxonomy. 11th edition. U.S. Department of Agriculture, Natural Resources Conservation Service. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053580 Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and Delaware Department of Natural Resources and Environmental Control, Wetlands Section. United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Waterways Experiment Station Technical Report Y-87-1. United States Department of Agriculture, Natural Resources Conservation Service. National forestry manual. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ home/?cid=nrcs142p2_053374 United States Department of Agriculture, Natural Resources Conservation Service. National range and pasture handbook. http://www.nrcs.usda.gov/wps/portal/nrcs/ detail/national/landuse/rangepasture/?cid=stelprdb1043084 16 United States Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 430-VI. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/soils/scientists/?cid=nrcs142p2_054242 United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/? cid=nrcs142p2_053624 United States Department of Agriculture, Soil Conservation Service. 1961. Land capability classification. U.S. Department of Agriculture Handbook 210. http:// www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052290.pdf Custom Soil Resource Report 17