Loading...
HomeMy WebLinkAboutSDP 2023-0014; CARLSBAD VILLAGE MIXED-USE - SB 330; SEWER STUDY - FEBRUARY 20, 2024; 2024-02-20 DEXTER WILSON ENGINEERING, INC. WATER ● WASTEWATER ● RECYCLED WATER CONSULTING ENGINEERS 2234 FARADAY AVENUE ● CARLSBAD, CA ● (760) 438-4422 SEWER STUDY FOR THE CARLSBAD VILLAGE MIXED USE PROJECT IN THE CITY OF CARLSBAD February 20, 2024 Andrew Cerrina February 20, 2024 Carlsbad Village Mixed Use Sewer Study DEXTER WILSON ENGINEERING, INC. PAGE 3 Purpose of Study The purpose of this study is to analyze the impact on the existing public sewer system with the addition of the development proposed by the Carlsbad Village Mixed Use project. Sewer System Design Criteria The design criteria used for the evaluation of the sewerage system impacts by the Carlsbad Village Mixed Use project are consistent with Volume 1 of the 2022 City of Carlsbad Engineering Standards: General Design Standards (2022 Volume 1 Engineering Standards). Appendix A includes excerpts from the 2022 Volume 1 Engineering Standards pertinent to this report for reference. Sewer Generation Rates Chapter 6 in the 2022 Volume 1 Engineering Standards identifies the average daily sewage flow to be 200 gallons per day (gpd) per Equivalent Dwelling Unit (EDU). Per Chapter 6, a multi-family residential unit is equal to 0.8 EDUs and 1,800 square feet of commercial building space is equal to 1 EDU. The sewer generation rate factors used for the Carlsbad Village Mixed Use project is presented in Table 1. TABLE 1 CARLSBAD VILLAGE MIXED USE SEWER GENERATION RATES 1 Land Use Generation Rate Multi-Family Residential 160 gpd/DU Commercial 200 gpd/1,800 sq. ft. 1. Based on Volume 1 of the 2022 City of Carlsbad Engineering Standards: General Design Standards, Chapter 6 – Design Criteria for Sewer Facilities. Andrew Cerrina February 20, 2024 Carlsbad Village Mixed Use Sewer Study DEXTER WILSON ENGINEERING, INC. PAGE 4 Peaking Factors The peaking factor for sewage flow is identified in the 2022 Volume 1 Engineering Standards. For average daily flows of less than 100,000 gpd, a peaking factor of 2.5 shall be used to determine peak daily flows. Manning’s “n” The gravity sewer analyses are made using a computer program which uses the Manning Equation for all of its calculations. The Manning’s “n” used by the computer program is held as a constant for all depths in a circular conduit. The value of Manning’s “n” used for this sewer study is 0.013 per the City of Carlsbad Utilities Department comment included in Appendix B of this report (from comment letter dated December 6, 2023) to account for the long-term roughness of the sewer system and simplified calculation approach that omits energy losses for flow through manholes and at junctions and flow transitions at changes in pipe slope. Depth and Velocity of Flow in Gravity Sewers Gravity sewer lines are designed to convey peak dry weather flow. Pipes that are 12-inches in diameter and smaller are designed to convey this flow with a maximum depth-to-diameter (d/D) ratio of 0.50. Pipes that are larger than 12-inches in diameter are designed for a maximum d/D ratio of 0.75. All gravity sewer lines are designed to convey peak wet weather flow for a maximum d/D ratio of 0.90. Exceedance of either the peak dry or peak wet weather flow depth criteria will trigger sewer improvements. Gravity sewer lines are designed to maintain a minimum velocity of 2.0 feet per second at peak dry weather flow to prevent the deposition of solids. Andrew Cerrina February 20, 2024 Carlsbad Village Mixed Use Sewer Study DEXTER WILSON ENGINEERING, INC. PAGE 5 Projected Sewer Generation Based on the sewage generation factors presented in Table 2, the estimated average sewer generation for the project is calculated in Table 2. TABLE 2 CARLSBAD VILLAGE MIXED USE AVERAGE DAILY SEWER FLOW Land Use Quantity Sewage Generation Factor Average Daily Flow Multi-Family Residential 218 DUs 160 gpd/DU 34,880 gpd Retail Space 13,800 sq. ft. 200 gpd/1,800 sq. ft. 1,533 gpd TOTAL 36,413 gpd Per Table 2, average daily sewer flow for the Carlsbad Village Mixed Use project is 36,413 gpd or 25.3 gpm. The peak daily flow is 91,033 gpd or 63.2 gpm (Average Daily Flow x 2.5). As stated previously, the existing site consists of commercial buildings that will be replaced with the proposed mixed-use residential project. Table 3 presents the average sewage generation for the site based on existing and proposed land uses, and the estimated net change in average daily sewage generation. Andrew Cerrina February 20, 2024 Carlsbad Village Mixed Use Sewer Study DEXTER WILSON ENGINEERING, INC. PAGE 6 TABLE 3 CARLSBAD VILLAGE MIXED USE EXISTING AND PROPOSED SEWAGE GENERATION Land Use Quantity Generation Factor Average Sewer Generation Existing Commercial 60,068 sq. ft. 1 200 gpd/1,800 sq. ft. 6,674 gpd Existing Subtotal 6,674 gpd Proposed Multi-Family Residential 218 DUs 160 gpd/DU 34,880 gpd Retail Space 13,800 sq. ft. 200 gpd/1,800 sq. ft. 1,533 gpd Proposed Subtotal 36,413 gpd Increase in Sewage Generation 29,739 gpd 1. The building space of the existing site was obtained from the County of San Diego’s San Diego Geographic Information Source (SANGIS). 1 EDU per 1,800 square feet of building space was used to calculate EDUs per Section 6.1.A.2.c of the 2022 City of Carlsbad Engineering Standards, Volume 1. Existing Sewer System The existing project site makes one connection to the existing sewer line in Oak Avenue near the southeast corner of the site and two connections to the existing sewer line in Carlsbad Village Drive to the north. The existing sewer system in the vicinity of the Carlsbad Village Mixed Use project includes a 6-inch gravity sewer line in Carlsbad Village Drive north of the project and a 6-inch gravity sewer line in Oak Avenue south of the project. Each of these 6- inch gravity sewer lines convey flow west to an existing 10-inch gravity sewer line in Harding Street. The 10-inch gravity sewer line in Harding Street conveys flow north to an existing 10-inch gravity sewer line in Grand Avenue that takes flow west to an existing 12-inch gravity sewer line in Jefferson Street. The 12-inch gravity sewer line in Jefferson Street connects to the existing 42-inch Vista/Carlsbad Interceptor Sewer just south of Grand Avenue. Figure 2 presents the existing sewer system in the vicinity of the project. Andrew Cerrina February 20, 2024 Carlsbad Village Mixed Use Sewer Study DEXTER WILSON ENGINEERING, INC. PAGE 8 Proposed Sewer System The Carlsbad Village Mixed Use project will connect to the public sewer system in Carlsbad Village Drive near the northwest corner of the project. Using temporary sewer flow monitoring data provided by the City, the flow depth criteria for 12-inch and smaller diameter sewer mains is exceeded under pre-project, current, conditions (without the addition of project flows) and, therefore, the existing 6-inch sewer line in Carlsbad Village Drive, from Harding Street to the northeast corner of the project site requires upsizing to an 8-inch sewer line and the existing 10-inch sewer line in Harding Street, from Carlsbad Village Drive to Grand Avenue, requires upsizing to a 12-inch sewer line. Per City standards, the project’s cost contribution to contract a larger pipe will be based on the proportionate share of project EDUs in accordance with Title 13 of the Carlsbad Municipal Code (13.08.035 and 13.08.040). Further, when project flows are evaluated for the Master Plan condition, which assumes all sites contributing to the sewer basin are developed to the maximum densities allowed for the zoning assumed in the 2019 Sewer Master Plan, the analysis shows that under pre-project conditions (without the addition of project flows), the existing 10-inch sewer line in Harding Street, from Carlsbad Village Drive to Grand Avenue, requires upsizing to a 12-inch sewer line. As stated above, the project’s cost contribution to contract a larger pipe will be based on the proportionate share of project EDUs in accordance with Title 13 of the Carlsbad Municipal Code (13.08.035 and 13.08.040). Figure 2 presents the proposed sewer system for the Carlsbad Village Mixed Use project. The private onsite gravity sewer system for the project will be designed to connect to the new 8- inch gravity sewer line in Carlsbad Village Drive. Sizing of the onsite private sewer system is outside of the scope of this report. Andrew Cerrina February 20, 2024 Carlsbad Village Mixed Use Sewer Study DEXTER WILSON ENGINEERING, INC. PAGE 9 Offsite Public Sewer System Analysis The offsite public sewer system analysis consists of determining peak sewer flows within all segments of the public sewer system that will be affected by the proposed development. The existing public sewer system was analyzed under existing flows and under existing flows plus proposed flows using sewer monitoring data provided by the City. The public sewer system was also analyzed under Master Plan flows. Offsite Sewer Analysis Using Temporary Sewer Flow Monitoring Existing sewer flows were determined using temporary sewer flow monitoring provided by the City, a sewer study dated December 6, 2017 and prepared by SB&O, Inc. for the Carlsbad Village Lofts project (located across the street from the proposed project), and a sewer study dated April 2022 and prepared by Pasco Laret Suiter & Associates, Inc. for the Hope Avenue Apartments project. Temporary sewer flow monitoring was performed at the manhole located at the intersection of Carlsbad Village Drive and Harding Street by V&A Consulting Engineers for the City. The sewer flow monitoring was conducted from February 2, 2023 to March 21, 2023. The flow monitoring measured flows in the existing 6-inch line in Carlsbad Village Drive and the existing 10-inch sewer line in Harding Street south of Carlsbad Village Drive. Appendix C contains a copy of the sewer flow monitoring report and corresponding flow summary information (V&A Report). Results of the temporary sewer flow monitoring show an average dry weather flow of 0.079 mgd in the existing 6-inch sewer line in Carlsbad Village Drive (see Page Site D-East – 8 of the V&A Report) and an average dry weather flow of 0.074 mgd in the existing 10-inch sewer line in Harding Street south of Carlsbad Village Drive (see Page Site D-South – 8 of the V&A Report). These average dry weather flows were multiplied by 2.5 in accordance with City standards to determine peak dry weather flows. Andrew Cerrina February 20, 2024 Carlsbad Village Mixed Use Sewer Study DEXTER WILSON ENGINEERING, INC. PAGE 10 The flow monitoring also captured peak wet weather flows during several rain events over the monitoring period. The peak wet weather flow in the existing 6-inch sewer line in Carlsbad Village Drive was measured to be 0.298 mgd (see Page Site D-East – 2 and 7 of the V&A Report) and the peak wet weather flow in the existing 10-inch sewer line in Harding Street south of Carlsbad Village Drive was measured to be 0.305 mgd (see Page Site D-South – 2 and 7 of V&A Report). The measured average and peak flows pertain to the specific storm event monitored and, although not regarded as the design peak wet weather flow, demonstrate that the existing sewer in Carlsbad Village Drive does not meet the flow depth criterion under pre-project conditions (see Appendix C, Site D-East – 9). Because the sewer flows from Carlsbad Village Drive combine with the sewer flows from Harding Street (south to north) at the flow monitoring manhole, the measured flows were added together to determine the total sewer flow conveyed north in Harding Street from Carlsbad Village Drive to Grand Avenue. Harding Street and Grand Avenue Existing Sewer Flows. Sewer flows for the lots located along Harding Street and Grand Avenue, downstream of the flow monitoring manhole, were calculated using the actual count of residential units or commercial building floor areas to determine existing EDUs. The building areas of the developed lots along Harding Street and Grand Avenue were obtained from the County of San Diego’s San Diego Geographic Information Source (SANGIS). To convert building space to EDUs, 1 EDU per 1,800 square feet of building space was used per Section 6.1.A.2.c of the 2022 City of Carlsbad Engineering Standards, Volume 1. Appendix D shows the building square footage of each lot along with EDU calculations. Jefferson Street Existing Sewer Flows. Sewer flows downstream of the intersection of Grand Avenue and Jefferson Street were provided by the City in the comment letter dated December 6, 2023 (see Appendix B). Sewer Flows for Recently Constructed Projects. Sewer flows for three recently constructed projects, that are located within the same sewer basin, as the Carlsbad Village Mixed Use project, were accounted for in the temporary sewer flow monitoring. These projects are the following: Andrew Cerrina February 20, 2024 Carlsbad Village Mixed Use Sewer Study DEXTER WILSON ENGINEERING, INC. PAGE 11 Carlsbad Village Lofts – 106 multi-family units and 10,578 sq. ft. of retail/office space Windsor Affordable Housing, Harding Building – 26 multi-family units Windsor Affordable Housing, Oak Building – 24 multi-family units The temporary sewer flow monitoring was conducted between February and March 2023, and each of the projects listed above had already been constructed and fully operational during this time. To account for near-term flows that will contribute to the same sewer basin, the Hope Avenue Apartments project, which has not been constructed but was recently approved, was added to the sewer flows. The Hope Avenue Apartments project will have 156 multi-family residential units; however, of the public sewer lines analyzed for the Carlsbad Village Mixed Use project, the sewer flows for the Hope Avenue Apartments project do not impact the public sewer lines in Carlsbad Village Drive, Harding Street, or Grand Avenue, only the public sewer line in Jefferson Street. As-built drawings were obtained from the City to determine the sewer slopes of the existing sewer system downstream of the project for the following analysis. The as-built drawings are included in Appendix E for reference. Existing Public Sewer System Under Existing Flows. The analysis in Appendix F presents the results for the existing sewer system under existing flows. Exhibit A presents a Manhole Diagram for the system. Peak Dry Weather Flow. The results of the peak dry weather analysis show that under existing peak dry weather flows the existing system has a maximum d/D ratio of 0.52. The maximum d/D ratio occurs in the sewer reach from Manhole 200 to Manhole 1068, which corresponds to the existing 10-inch gravity sewer line in Harding Street. Flow velocities in the existing public sewer system range from 2.1 fps to 6.7 fps under existing flows. The maximum allowable d/D ratio under peak dry weather flow is 0.50 for sewer lines that are 12-inches in diameter and smaller. Andrew Cerrina February 20, 2024 Carlsbad Village Mixed Use Sewer Study DEXTER WILSON ENGINEERING, INC. PAGE 12 Peak Wet Weather Flow. Under peak wet weather flow, the maximum d/D ratio in the existing system is 0.70 in the sewer reach from Manhole 200 to Manhole 1068, which corresponds to the existing 10-inch gravity sewer line in Harding Street. The maximum allowable d/D ratio under peak wet weather flow is 0.90. As previously mentioned, under measured peak wet weather flows, the existing 6-inch sewer line in Carlsbad Village Drive does not meet the flow depth criterion under pre-project conditions for peak wet weather flow (see Appendix C, Site D-East – 9). Existing Public Sewer System Under Existing Plus Project Flows. The analysis in Appendix G presents the results for the existing sewer system under existing plus project flows. Exhibit A presents a Manhole Diagram for the system. Peak Dry Weather Flow. The results of the peak dry weather analysis show that under existing plus project flows the maximum peak dry weather flow d/D ratio increases from 0.52 to 0.57 in the existing 10-inch sewer line in Harding Street (from Manhole 200 to Manhole 1068). Flow velocities in the existing public sewer system range from 2.2 fps to 6.9 fps under existing plus project flows. The maximum allowable d/D ratio under peak dry weather flow is 0.50 for sewer lines that are 12-inches in diameter and smaller. Peak Wet Weather Flow. Under peak wet weather flow, the maximum d/D in the existing system increases from 0.70 to 0.77 in the existing 10-inch sewer line in Harding Street (from Manhole 200 to Manhole 1068). The maximum allowable d/D ratio under peak wet weather flow is 0.90. Based on the results of the public sewer analysis using temporary sewer flow monitoring data, the flow depth criteria for 12-inch and smaller diameter sewer mains is exceeded under pre-project conditions (without the addition of project flows) and, therefore in accordance with City standards the existing 6-inch sewer line in Carlsbad Village Drive, from Harding Street to the northeast corner of the project site, requires upsizing to an 8-inch sewer line and the existing 10-inch sewer line in Harding Street, from Carlsbad Village Drive to Grand Avenue, requires upsizing to a 12-inch sewer line. Andrew Cerrina February 20, 2024 Carlsbad Village Mixed Use Sewer Study DEXTER WILSON ENGINEERING, INC. PAGE 13 Proposed Public Sewer System Under Existing Plus Project Flows. The analysis in Appendix H presents the results for the sewer system under existing plus project flows after A) the existing 6-inch sewer line in Carlsbad Village Drive has been upgraded to an 8-inch sewer line, and B) the existing 10-inch sewer line in Harding Street has been upgraded to a 12-inch sewer line. Exhibit A presents a Manhole Diagram for the system. Peak Dry Weather Flow. The results of the peak dry weather analysis show that under existing plus project peak dry weather flows the proposed system has a maximum d/D ratio of 0.43. The maximum d/D ratio occurs in the sewer reach from Manhole 5258 to Manhole 1068, which corresponds to the proposed 12-inch gravity sewer line in Harding Street. Flow velocities in the public sewer system range from 2.2 fps to 6.9 fps under existing flows. The maximum allowable d/D ratio under peak dry weather flow is 0.50 for sewer lines that are 12-inches in diameter and smaller. Peak Wet Weather Flow. Under existing plus project peak wet weather flow, the maximum d/D ratio in the proposed system is 0.55 in the sewer reach from Manhole 200 to Manhole 1068, which corresponds to the proposed 12-inch gravity sewer line in Harding Street. The maximum allowable d/D ratio under peak wet weather flow is 0.90. Offsite Sewer Analysis Using Master Plan Flows The existing and proposed public sewer system was analyzed under Master Plan flows provided by the City, which assumes all sites contributing to the sewer basin are developed to the maximum densities allowed for the zoning assumed in the 2019 Sewer Master Plan. The Master Plan analysis in the 2019 Sewer Master Plan Update does not include the development densities approved in the Village & Barrio Master Plan, which was adopted in 2019. Existing Public Sewer System Under Master Plan Flows. The analysis in Appendix I presents the results for the existing sewer system under Master Plan flows. Exhibit A presents a Manhole Diagram for the system. Andrew Cerrina February 20, 2024 Carlsbad Village Mixed Use Sewer Study DEXTER WILSON ENGINEERING, INC. PAGE 14 Peak Dry Weather Flow. The results of the peak dry weather analysis show that under Master Plan peak dry weather flows the existing system has a maximum d/D ratio of 0.67. The maximum d/D ratio occurs in the sewer reach from Manhole 200 to Manhole 1068, which corresponds to the existing 10-inch gravity sewer line in Harding Street. Flow velocities in the existing public sewer system range from 2.3 fps to 6.7 fps under existing flows. The maximum allowable d/D ratio under peak dry weather flow is 0.50 for sewer lines that are 12-inches in diameter and smaller. Peak Wet Weather Flow. Under Master Plan peak wet weather flow, the maximum d/D ratio in the existing system is greater than 1.0 in the sewer reach from Manhole 5258 to Manhole 1068, which corresponds to the existing 10-inch gravity sewer line in Harding Street. The maximum allowable d/D ratio under peak wet weather flow is 0.90. Based on the results of the existing public sewer system under Master Plan flows without the project, the maximum d/D ratio is exceeded in both peak dry and peak wet scenarios in the existing 10-inch sewer line in Harding Street. This indicates that the 10-inch sewer line in Harding Street, between Carlsbad Village Drive and Grand Avenue, requires a larger sewer main diameter under pre-project conditions (without addition of project flows). Existing Public Sewer System Under Master Plan Plus Project Flows. The analysis in Appendix J presents the results for the existing sewer system under Master Plan plus project flows. Exhibit A presents a Manhole Diagram for the system. Peak Dry Weather Flow. The results of the peak dry weather analysis show that under Master Plan plus project flows the maximum peak dry weather flow d/D ratio increases from 0.67 to 0.73 in the existing 10-inch sewer line in Harding Street (from Manhole 200 to Manhole 1068). Flow velocities in the existing public sewer system range from 2.3 fps to 6.9 fps under Master Plan plus project flows. The maximum allowable d/D ratio under peak dry weather flow is 0.50 for sewer lines that are 12-inches in diameter and smaller. Peak Wet Weather Flow. Under Master Plan plus project peak wet weather flow, the maximum d/D ratio in the existing system remains greater than 1.0 from Manhole 5258 to Manhole 1068, which corresponds to the existing 10-inch gravity sewer line in Harding Street. The maximum allowable d/D ratio under peak wet weather flow is 0.90. Andrew Cerrina February 20, 2024 Carlsbad Village Mixed Use Sewer Study DEXTER WILSON ENGINEERING, INC. PAGE 15 Based on the results of the existing public sewer analysis using Master Plan flows, the maximum allowable d/D ratio is exceeded in the existing 10-inch sewer line in Harding Street, between Carlsbad Village Drive and Grand Avenue, with and without the project. The 10-inch sewer line would be required to be upgraded using Master Plan flows with or without the project. Proposed Public Sewer System Under Master Plan Plus Project Flows. The analysis in Appendix K presents the results for the sewer system under Master Plan plus project flows after A) the existing 6-inch sewer line in Carlsbad Village Drive has been upgraded to an 8- inch sewer line, and B) the existing 10-inch sewer line in Harding Street has been upgraded to a 12-inch sewer line. Exhibit A presents a Manhole Diagram for the system. Peak Dry Weather Flow. The results of the peak dry weather analysis show that under Master Plan plus project peak dry weather flows the proposed system has a maximum d/D ratio of 0.53. The maximum d/D ratio occurs in the sewer reach from Manhole 5258 to Manhole 1068, which corresponds to the proposed 12-inch gravity sewer line in Harding Street. Flow velocities in the public sewer system range from 2.4 fps to 6.9 fps under existing flows. The maximum allowable d/D ratio under peak dry weather flow is 0.50 for sewer lines that are 12-inches in diameter and smaller. Because the analysis assumes all sites contributing to the sewer basin are fully built out (Master Plan plus project flows), a 12-inch public sewer line is recommended. The final size of the proposed public sewer line in Harding Street will be determined during final engineering. Peak Wet Weather Flow. Under Master Plan plus project peak wet weather flow, the maximum d/D ratio in the proposed system is 0.64 in the sewer reach from Manhole 5258 to Manhole 1068, which corresponds to the proposed 12-inch gravity sewer line in Harding Street. The maximum allowable d/D ratio under peak wet weather flow is 0.90. Andrew Cerrina February 20, 2024 Carlsbad Village Mixed Use Sewer Study DEXTER WILSON ENGINEERING, INC. PAGE 16 Conclusions and Recommendations The following conclusions have been made related to providing sewer service to the Carlsbad Village Mixed Use project. 1. Existing sewer service is provided to the project site by the City of Carlsbad. 2. The Carlsbad Village Mixed Use project will receive sewer service from the City of Carlsbad. 3. The existing and proposed public sewer system is presented in Figure 2. 4. The project will connect to the proposed 8-inch sewer line in Carlsbad Village Drive near the northwest corner of the project site. 5. Using temporary sewer flow monitoring data provided by the City, the flow depth criteria for 12-inch and smaller diameter sewer mains is exceeded under pre-project conditions (without the addition of project flows) in Carlsbad Village Drive and Harding Street. Therefore, in accordance with City standards, the existing 6-inch sewer line in Carlsbad Village Drive, from Harding Street to the northeast corner of the project site, requires upsizing to an 8-inch sewer line, and the existing 10-inch sewer line in Harding Street, from Carlsbad Village Drive to Grand Avenue, requires upsizing to a 12-inch sewer line. 6. When project flows are evaluated for the Master Plan condition, which assumes all sites contributing to the sewer basin are developed to the maximum densities allowed for the zoning assumed in the 2019 Sewer Master Plan, the analysis shows that the existing 10-inch sewer main in Harding Street between Carlsbad Village Drive and Grand Avenue requires upsizing to a 12-inch sewer line. 7. The project’s cost contribution to contract a larger pipe in both Carlsbad Village Drive and Harding Street will be based on the proportionate share of project EDUs in accordance with Title 13 of the Carlsbad Municipal Code (13.08.035 and 13.08.040). APPENDIX A CITY OF CARLSBAD SEWER SYSTEM DESIGN CRITERIA APPENDIX B CITY OF CARLSBAD UTILITIES DEPARTMENT COMMENT RE: MANNING’S “N” VALUE Community & Economic Development Planning Division 1635 Faraday Avenue  Carlsbad, CA 92008  760-602-4600  760-602-8560 fax Memorandum DATE 12/6/2023 To: Jason Goff From: Neil Irani Via Planning Division Request for Review Re: CARLSBAD VILLAGE MIXED USE– SDP2023-0014 Issues of Concern: 1. Address all civil site plan utility markups. 2. Address all markups to sewer study. 3. Upsizing of sewer gravity main in Harding required, see sewer study comments. 4. Conditions of approval for the scope of sewer and water reimbursement agreements must be finalized prior to discretionary approval. Developer to contact CMWD to discuss scope of reimbursement for public water and sewer work. Please provide the following information and/or document(s) with the requested number of copies as specified. Attachments: 1. Civil site plan, sewer study comments (PDF) Information/Document # of Copies Submittal Form Admin. Purposes Only Sewer Study 1 PDF Revised Civil Plan Set 1 HC/PDF 8/7/2023 FOR:SHT 1 OF 1 1135-001 BY:REFER TO PLAN SHEET: M.G.D.C.F.S. 5259 6538 140,000 0.140 0.217 6 3.00 0.087356 0.14712 0.29 0.1929 4.49 6538 5258 140,000 0.140 0.217 6 2.80 0.090422 0.14976 0.30 0.1978 4.38 5258B 200 321,850 0.322 0.498 10 0.28 0.168346 0.34751 0.42 0.3101 2.31 200 1068 326,950 0.327 0.506 10 0.28 0.171013 0.35058 0.42 0.3137 2.32 1068 1060 360,150 0.360 0.557 10 1.16 0.092551 0.25261 0.30 0.2011 3.99 1060 1061 490,000 0.490 0.758 12 2.89 0.049060 0.21968 0.22 0.1278 5.93 1061 1062 490,000 0.490 0.758 12 4.00 0.041701 0.20262 0.20 0.1139 6.66 Min Slope Max dn/D 0.28 0.42 A. Flows added to sewer flow monitoring data. LINE SIZE (inches) DATE:SEWER STUDY SUMMARY Carlsbad Village Mixed Use Project - Existing System, Existing PDWF JOB NUMBER:Dexter Wilson Engineering, Inc. LINE FROM TO EXISTING PEAK FLOW (gpd) PEAK FLOW (DESIGN FLOW)DESIGN SLOPE (%)DEPTH K' (1) SB&O Report Model Data Carlsbad Village Lofts South (53 DUs + 10,578 retail sqft) Windsor Pointe Apts - Oak & Harding (40 DUs) 1.52 Commercial Acres (14.7 EDUs) 1.05 Commerical Acres (10.2 EDUs) dn (feet)dn/D(2)Ca for Velocity(3)VELOCITY (f.p.s.) Carlsbad Village Lofts North (53 DUs) 1.38 Commercial Acres (13.4 EDUs) Existing Carlsbad Village Mixed Use Site Peak Flow = 20,000 gpd COMMENTS A 1 K' based on n = 0.011 2 dn/D using K' in Brater King Table 7-14 3 From Brater King Table 7-4 based on dn/D \\ARTIC\Eng\1135001\Sewer\2023-08-11 Carlsbad Village Offsite Sewer Analysis_City FM.xlsx Existing PDWF 8/7/2023 FOR:SHT 1 OF 1 1135-001 BY:REFER TO PLAN SHEET: M.G.D.C.F.S. 5259 6538 140,000 0 140,000 0.140 0.217 8 3.00 0.040562 0.13327 0.20 0.1117 4.36 6538 5258 120,000 91,033 211,033 0.211 0.327 8 2.80 0.063289 0.16652 0.25 0.1533 4.79 5258 200 301,850 91,033 392,883 0.393 0.608 10 0.28 0.205500 0.38874 0.47 0.3592 2.44 Carlsbad Village Lofts South (53 DUs + 10,578 retail sqft) Windsor Pointe Apts - Oak & Harding (40 DUs) 1.52 Commercial Acres (14.7 EDUs) 200 1068 306,950 91,033 397,983 0.398 0.616 10 0.28 0.208167 0.39163 0.47 0.3627 2.45 1.05 Commerical Acres (10.2 EDUs) 1068 1060 340,150 91,033 431,183 0.431 0.667 10 1.16 0.110805 0.27748 0.33 0.2288 4.20 Carlsbad Village Lofts North (53 DUs) 1.38 Commercial Acres (13.4 EDUs) 1060 1061 470,000 91,033 561,033 0.561 0.868 12 2.89 0.056172 0.23515 0.24 0.1408 6.16 SB&O Report Model Data 1061 1062 470,000 91,033 561,033 0.561 0.868 12 4.00 0.047746 0.21670 0.22 0.1254 6.92 Min Slope Max dn/D 0.28 0.47 A. Existing peak flow of 20,000 gpd for existing Carlsbad Village Mixed Use site is subtracted out downstream of Manhole 6538 due to proposed redevelopment. B. Flows added to sewer flow monitoring data. COMBINED PEAK FLOW (gpd) DATE:SEWER STUDY SUMMARY Carlsbad Village Mixed Use Project - Proposed System, Existing + Project PDWF JOB NUMBER:Dexter Wilson Engineering, Inc. LINE FROM TO EXISTING PEAK FLOW (gpd) A PROPOSED PROJECT PEAK FLOW (gpd) Ca for Velocity(3)VELOCITY (f.p.s.)COMMENTS B PEAK FLOW (DESIGN FLOW)LINE SIZE (inches) DESIGN SLOPE (%)DEPTH K' (1)dn (feet)dn/D(2) 1 K' based on n = 0.013 2 dn/D using K' in Brater King Table 7-14 3 From Brater King Table 7-4 based on dn/D \\ARTIC\Eng\1135001\Sewer\2023-08-11 Carlsbad Village Offsite Sewer Analysis_City FM.xlsx Existing + Project PDWF APPENDIX C TEMPORARY SEWER FLOW MONITORING REPORT (V&A REPORT) Appendix A Flow Monitoring Site Reports: Data, Graphs, Information Monitoring Site:Site D East Location:Carlsbad Village Drive and Harding Street Sanitary Sewer Flow Monitoring City of Carlsbad | Carlsbad, California Vicinity Map: Site D East Data Summary Report February 02, 2023 - March 21, 2023 | Site D-East - 1 SITE D EAST Site Information Appendix A Flow Monitoring Site Reports: Data, Graphs, Information MH ID:MH 10C-53 Measured Pipe Diameter:6 inches ADWF:0.079 mgd Peak Measured Flow:0.298 mgd Flow Sketch Satellite Map Street View Sanitary Map Location:Carlsbad Village Drive and Harding Street Rim Elevation:64 feet Plan View Coordinates:117.3446° W, 33.1619° N Expected Pipe Diameter:6 inches Sediment:None | Site D-East - 2 SITE D EAST Additional Site Photos Appendix A Flow Monitoring Site Reports: Data, Graphs, Information Effluent Pipe Monitored East Influent Pipe | Site D-East - 3 SITE D EAST Additional Site Photos Appendix A Flow Monitoring Site Reports: Data, Graphs, Information South Influent Pipe | Site D-East - 4 SITE D EAST Period Flow Summary: Daily Flow Totals Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0.18 0.20 2/ 2 2/ 4 2/ 6 2/ 8 2/ 1 0 2/ 1 2 2/ 1 4 2/ 1 6 2/ 1 8 2/ 2 0 2/ 2 2 2/ 2 4 2/ 2 6 2/ 2 8 3/ 2 3/ 4 3/ 6 3/ 8 3/ 1 0 3/ 1 2 3/ 1 4 3/ 1 6 3/ 1 8 3/ 2 0 Fl o w ( M G a l ) 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 Ra i n f a l l ( i n / d a y ) Realtime Holiday Rainfall ADWF 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0.18 0.20 2/ 2 2/ 4 2/ 6 2/ 8 2/ 1 0 2/ 1 2 2/ 1 4 2/ 1 6 2/ 1 8 2/ 2 0 2/ 2 2 2/ 2 4 2/ 2 6 2/ 2 8 3/ 2 3/ 4 3/ 6 3/ 8 3/ 1 0 3/ 1 2 3/ 1 4 3/ 1 6 3/ 1 8 3/ 2 0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 Realtime Weekend 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0.18 0.20 2/ 2 2/ 4 2/ 6 2/ 8 2/ 1 0 2/ 1 2 2/ 1 4 2/ 1 6 2/ 1 8 2/ 2 0 2/ 2 2 2/ 2 4 2/ 2 6 2/ 2 8 3/ 2 3/ 4 3/ 6 3/ 8 3/ 1 0 3/ 1 2 3/ 1 4 3/ 1 6 3/ 1 8 3/ 2 0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 Realtime Weekday Total Rainfall: 9.19 inches Avg Daily Flow: 0.091 MGal Peak Daily Flow: 0.176 MGal Min Daily Flow: 0.073 MGal | Site D-East - 5 SITE D EAST Flow Summary: 2/2/2023 to 2/25/2023 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.00 0.05 0.10 0.15 0.20 0.25 0.30 02/02 02/03 02/04 02/05 02/06 02/07 02/08 02/09 02/10 02/11 02/12 02/13 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 Ra i n f a l l ( i n / h r ) Rain Flow ADWF 0.00 0.05 0.10 0.15 0.20 0.25 0.30 02/14 02/15 02/16 02/17 02/18 02/19 02/20 02/21 02/22 02/23 02/24 02/25 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 Ra i n f a l l ( i n / h r ) Period Rainfall: 2.56 inches Period Avg Flow: 0.081 mgd Period Peak Flow: 0.202 mgd Period Min Flow: 0.015 mgd | Site D-East - 6 SITE D EAST Flow Summary: 2/26/2023 to 3/21/2023 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.00 0.05 0.10 0.15 0.20 0.25 0.30 02/26 02/27 02/28 03/01 03/02 03/03 03/04 03/05 03/06 03/07 03/08 03/09 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 Ra i n f a l l ( i n / h r ) Rain Flow ADWF 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 03/10 03/11 03/12 03/13 03/14 03/15 03/16 03/17 03/18 03/19 03/20 03/21 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 Ra i n f a l l ( i n / h r ) Period Rainfall: 6.60 inches Period Avg Flow: 0.102 mgd Period Peak Flow: 0.298 mgd Period Min Flow: 0.023 mgd | Site D-East - 7 SITE D EAST Average Dry Weather Flow Hydrographs Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 0: 0 0 1: 0 0 2: 0 0 3: 0 0 4: 0 0 5: 0 0 6: 0 0 7: 0 0 8: 0 0 9: 0 0 10 : 0 0 11 : 0 0 12 : 0 0 13 : 0 0 14 : 0 0 15 : 0 0 16 : 0 0 17 : 0 0 18 : 0 0 19 : 0 0 20 : 0 0 21 : 0 0 22 : 0 0 23 : 0 0 Fl o w ( m g d ) Mon-Thurs Friday Saturday Sunday Time of Day 0.079mgd ADWF: | Site D-East - 8 SITE D EAST Site Capacity and Surcharge Summary Appendix A Flow Monitoring Site Reports: Data, Graphs, Information Surcharged 0.6 inches over crown Peak Measured Level:6.59 Peak d/D Ratio:1.10 Pipe Diameter:6 inches inches Realtime Flow Levels with Rainfall Data over Peak Level Period Diameter 75% d/D 0 1 2 3 4 5 6 7 8 9 02 / 0 2 02 / 0 4 02 / 0 6 02 / 0 8 02 / 1 0 02 / 1 2 02 / 1 4 02 / 1 6 02 / 1 8 02 / 2 0 02 / 2 2 02 / 2 4 Le v e l ( i n ) 02 / 2 6 02 / 2 8 03 / 0 2 03 / 0 4 03 / 0 6 03 / 0 8 03 / 1 0 03 / 1 2 03 / 1 4 03 / 1 6 03 / 1 8 03 / 2 0 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0 Ra i n ( i n / h r ) | Site D-East - 9 SITE D EAST Weekly Level, Velocity and Flow Hydrographs 1/30/2023 to 2/6/2023 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 Mon Tue Wed Thu Fri Sat Sun Le v e l ( i n ) Lev 0.0 0.5 1.0 1.5 2.0 2.5 3.0 Ve l o c i t y ( f p s ) Vel 0.00 0.05 0.10 0.15 0.20 0.25 0.30 1/30 1/31 2/1 2/2 2/3 2/4 2/5 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 Ra i n ( i n / h r ) Rain Flow ADWF Avg Level: 2.58 in. Peak Level: 3.52 in. Min Level: 1.35 in. Avg Velocity: 1.45 fps Peak Velocity: 2.01 fps Min Velocity: 0.68 fps Avg Flow: 0.081 mgd Peak Flow: 0.146 mgd Min Flow: 0.015 mgd | Site D-East - 10 SITE D EAST Weekly Level, Velocity and Flow Hydrographs 2/6/2023 to 2/13/2023 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 Mon Tue Wed Thu Fri Sat Sun Le v e l ( i n ) Lev 0.0 0.5 1.0 1.5 2.0 2.5 3.0 Ve l o c i t y ( f p s ) Vel 0.00 0.05 0.10 0.15 0.20 0.25 0.30 2/6 2/7 2/8 2/9 2/10 2/11 2/12 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 Ra i n ( i n / h r ) Rain Flow ADWFTotal Weekly Rainfall: 0.14 inches Avg Level: 2.53 in. Peak Level: 3.47 in. Min Level: 1.36 in. Avg Velocity: 1.44 fps Peak Velocity: 2.03 fps Min Velocity: 0.66 fps Avg Flow: 0.078 mgd Peak Flow: 0.146 mgd Min Flow: 0.015 mgd | Site D-East - 11 SITE D EAST Weekly Level, Velocity and Flow Hydrographs 2/13/2023 to 2/20/2023 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 Mon Tue Wed Thu Fri Sat Sun Le v e l ( i n ) Lev 0.0 0.5 1.0 1.5 2.0 2.5 3.0 Ve l o c i t y ( f p s ) Vel 0.00 0.05 0.10 0.15 0.20 0.25 0.30 2/13 2/14 2/15 2/16 2/17 2/18 2/19 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 Ra i n ( i n / h r ) Rain Flow ADWFTotal Weekly Rainfall: 0.03 inches Avg Level: 2.53 in. Peak Level: 3.79 in. Min Level: 1.56 in. Avg Velocity: 1.47 fps Peak Velocity: 2.03 fps Min Velocity: 0.66 fps Avg Flow: 0.079 mgd Peak Flow: 0.169 mgd Min Flow: 0.018 mgd | Site D-East - 12 SITE D EAST Weekly Level, Velocity and Flow Hydrographs 2/20/2023 to 2/27/2023 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 Mon Tue Wed Thu Fri Sat Sun Le v e l ( i n ) Lev 0.0 0.5 1.0 1.5 2.0 2.5 3.0 Ve l o c i t y ( f p s ) Vel 0.00 0.05 0.10 0.15 0.20 0.25 0.30 2/20 2/21 2/22 2/23 2/24 2/25 2/26 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 Ra i n ( i n / h r ) Rain Flow ADWFTotal Weekly Rainfall: 2.41 inches Avg Level: 2.81 in. Peak Level: 6.59 in. Min Level: 1.47 in. Avg Velocity: 1.45 fps Peak Velocity: 2.14 fps Min Velocity: 0.64 fps Avg Flow: 0.087 mgd Peak Flow: 0.202 mgd Min Flow: 0.016 mgd | Site D-East - 13 SITE D EAST Weekly Level, Velocity and Flow Hydrographs 2/27/2023 to 3/6/2023 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 Mon Tue Wed Thu Fri Sat Sun Le v e l ( i n ) Lev 0.0 0.5 1.0 1.5 2.0 2.5 3.0 Ve l o c i t y ( f p s ) Vel 0.00 0.05 0.10 0.15 0.20 0.25 0.30 2/27 2/28 3/1 3/2 3/3 3/4 3/5 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 Ra i n ( i n / h r ) Rain Flow ADWFTotal Weekly Rainfall: 0.88 inches Avg Level: 2.78 in. Peak Level: 3.63 in. Min Level: 1.74 in. Avg Velocity: 1.53 fps Peak Velocity: 2.02 fps Min Velocity: 0.80 fps Avg Flow: 0.092 mgd Peak Flow: 0.158 mgd Min Flow: 0.025 mgd | Site D-East - 14 SITE D EAST Weekly Level, Velocity and Flow Hydrographs 3/6/2023 to 3/13/2023 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 Mon Tue Wed Thu Fri Sat Sun Le v e l ( i n ) Lev 0.0 0.5 1.0 1.5 2.0 2.5 3.0 Ve l o c i t y ( f p s ) Vel 0.00 0.05 0.10 0.15 0.20 0.25 0.30 3/6 3/7 3/8 3/9 3/10 3/11 3/12 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 Ra i n ( i n / h r ) Rain Flow ADWFTotal Weekly Rainfall: 1.04 inches Avg Level: 2.83 in. Peak Level: 4.09 in. Min Level: 1.76 in. Avg Velocity: 1.52 fps Peak Velocity: 2.18 fps Min Velocity: 0.72 fps Avg Flow: 0.094 mgd Peak Flow: 0.195 mgd Min Flow: 0.023 mgd | Site D-East - 15 SITE D EAST Weekly Level, Velocity and Flow Hydrographs 3/13/2023 to 3/20/2023 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 Mon Tue Wed Thu Fri Sat Sun Le v e l ( i n ) Lev 0.0 0.5 1.0 1.5 2.0 2.5 3.0 Ve l o c i t y ( f p s ) Vel 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 3/13 3/14 3/15 3/16 3/17 3/18 3/19 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 Ra i n ( i n / h r ) Rain Flow ADWFTotal Weekly Rainfall: 2.79 inches Avg Level: 3.18 in. Peak Level: 5.34 in. Min Level: 2.01 in. Avg Velocity: 1.65 fps Peak Velocity: 2.40 fps Min Velocity: 0.90 fps Avg Flow: 0.116 mgd Peak Flow: 0.287 mgd Min Flow: 0.034 mgd | Site D-East - 16 SITE D EAST Weekly Level, Velocity and Flow Hydrographs 3/20/2023 to 3/27/2023 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 Mon Tue Wed Thu Fri Sat Sun Le v e l ( i n ) Lev 0.0 0.5 1.0 1.5 2.0 2.5 3.0 Ve l o c i t y ( f p s ) Vel 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 3/20 3/21 3/22 3/23 3/24 3/25 3/26 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 Ra i n ( i n / h r ) Rain Flow ADWFTotal Weekly Rainfall: 1.91 inches Avg Level: 3.29 in. Peak Level: 6.08 in. Min Level: 2.24 in. Avg Velocity: 1.63 fps Peak Velocity: 2.34 fps Min Velocity: 0.79 fps Avg Flow: 0.119 mgd Peak Flow: 0.298 mgd Min Flow: 0.035 mgd | Site D-East - 17 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information Monitoring Site:Site D South Location:Carlsbad Village Drive and Harding Street Sanitary Sewer Flow Monitoring City of Carlsbad | Carlsbad, California Vicinity Map: Site D South Data Summary Report February 02, 2023 - March 21, 2023 | Site D-South - 1 SITE D SOUTH Site Information Appendix A Flow Monitoring Site Reports: Data, Graphs, Information MH ID:MH 10C-53 Measured Pipe Diameter:10 inches ADWF:0.074 mgd Peak Measured Flow:0.305 mgd Flow Sketch Satellite Map Street View Sanitary Map Location:Carlsbad Village Drive and Harding Street Rim Elevation:64 feet Plan View Coordinates:117.3446° W, 33.1619° N Expected Pipe Diameter:10 inches Sediment:None | Site D-South - 2 SITE D SOUTH Additional Site Photos Appendix A Flow Monitoring Site Reports: Data, Graphs, Information Effluent Pipe Monitored South Influent Pipe | Site D-South - 3 SITE D SOUTH Additional Site Photos Appendix A Flow Monitoring Site Reports: Data, Graphs, Information East Influent Pipe | Site D-South - 4 SITE D SOUTH Period Flow Summary: Daily Flow Totals Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 2/ 2 2/ 4 2/ 6 2/ 8 2/ 1 0 2/ 1 2 2/ 1 4 2/ 1 6 2/ 1 8 2/ 2 0 2/ 2 2 2/ 2 4 2/ 2 6 2/ 2 8 3/ 2 3/ 4 3/ 6 3/ 8 3/ 1 0 3/ 1 2 3/ 1 4 3/ 1 6 3/ 1 8 3/ 2 0 Fl o w ( M G a l ) 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 Ra i n f a l l ( i n / d a y ) Realtime Holiday Rainfall ADWF 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 2/ 2 2/ 4 2/ 6 2/ 8 2/ 1 0 2/ 1 2 2/ 1 4 2/ 1 6 2/ 1 8 2/ 2 0 2/ 2 2 2/ 2 4 2/ 2 6 2/ 2 8 3/ 2 3/ 4 3/ 6 3/ 8 3/ 1 0 3/ 1 2 3/ 1 4 3/ 1 6 3/ 1 8 3/ 2 0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 Realtime Weekend 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 2/ 2 2/ 4 2/ 6 2/ 8 2/ 1 0 2/ 1 2 2/ 1 4 2/ 1 6 2/ 1 8 2/ 2 0 2/ 2 2 2/ 2 4 2/ 2 6 2/ 2 8 3/ 2 3/ 4 3/ 6 3/ 8 3/ 1 0 3/ 1 2 3/ 1 4 3/ 1 6 3/ 1 8 3/ 2 0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 Realtime Weekday Total Rainfall: 9.19 inches Avg Daily Flow: 0.084 MGal Peak Daily Flow: 0.132 MGal Min Daily Flow: 0.066 MGal | Site D-South - 5 SITE D SOUTH Flow Summary: 2/2/2023 to 2/25/2023 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.00 0.05 0.10 0.15 0.20 0.25 0.30 02/02 02/03 02/04 02/05 02/06 02/07 02/08 02/09 02/10 02/11 02/12 02/13 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 Ra i n f a l l ( i n / h r ) Rain Flow ADWF 0.00 0.05 0.10 0.15 0.20 0.25 0.30 02/14 02/15 02/16 02/17 02/18 02/19 02/20 02/21 02/22 02/23 02/24 02/25 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 Ra i n f a l l ( i n / h r ) Period Rainfall: 2.56 inches Period Avg Flow: 0.075 mgd Period Peak Flow: 0.184 mgd Period Min Flow: 0.012 mgd | Site D-South - 6 SITE D SOUTH Flow Summary: 2/26/2023 to 3/21/2023 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.00 0.05 0.10 0.15 0.20 0.25 0.30 02/26 02/27 02/28 03/01 03/02 03/03 03/04 03/05 03/06 03/07 03/08 03/09 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 Ra i n f a l l ( i n / h r ) Rain Flow ADWF 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 03/10 03/11 03/12 03/13 03/14 03/15 03/16 03/17 03/18 03/19 03/20 03/21 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 Ra i n f a l l ( i n / h r ) Period Rainfall: 6.60 inches Period Avg Flow: 0.092 mgd Period Peak Flow: 0.305 mgd Period Min Flow: 0.022 mgd | Site D-South - 7 SITE D SOUTH Average Dry Weather Flow Hydrographs Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.00 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0: 0 0 1: 0 0 2: 0 0 3: 0 0 4: 0 0 5: 0 0 6: 0 0 7: 0 0 8: 0 0 9: 0 0 10 : 0 0 11 : 0 0 12 : 0 0 13 : 0 0 14 : 0 0 15 : 0 0 16 : 0 0 17 : 0 0 18 : 0 0 19 : 0 0 20 : 0 0 21 : 0 0 22 : 0 0 23 : 0 0 Fl o w ( m g d ) Mon-Thurs Friday Saturday Sunday Time of Day 0.074mgd ADWF: | Site D-South - 8 SITE D SOUTH Site Capacity and Surcharge Summary Appendix A Flow Monitoring Site Reports: Data, Graphs, Information Peak Measured Level:6.93 Peak d/D Ratio:0.69 Pipe Diameter:10 inches inches Realtime Flow Levels with Rainfall Data over Peak Level Period Diameter 75% d/D 0 2 4 6 8 10 12 02 / 0 2 02 / 0 4 02 / 0 6 02 / 0 8 02 / 1 0 02 / 1 2 02 / 1 4 02 / 1 6 02 / 1 8 02 / 2 0 02 / 2 2 02 / 2 4 Le v e l ( i n ) 02 / 2 6 02 / 2 8 03 / 0 2 03 / 0 4 03 / 0 6 03 / 0 8 03 / 1 0 03 / 1 2 03 / 1 4 03 / 1 6 03 / 1 8 03 / 2 0 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0 Ra i n ( i n / h r ) | Site D-South - 9 SITE D SOUTH Weekly Level, Velocity and Flow Hydrographs 1/30/2023 to 2/6/2023 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 Mon Tue Wed Thu Fri Sat Sun Le v e l ( i n ) Lev 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 Ve l o c i t y ( f p s ) Vel 0.00 0.05 0.10 0.15 0.20 0.25 0.30 1/30 1/31 2/1 2/2 2/3 2/4 2/5 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 Ra i n ( i n / h r ) Rain Flow ADWF Avg Level: 3.21 in. Peak Level: 4.30 in. Min Level: 2.55 in. Avg Velocity: 0.78 fps Peak Velocity: 1.34 fps Min Velocity: 0.32 fps Avg Flow: 0.079 mgd Peak Flow: 0.184 mgd Min Flow: 0.023 mgd | Site D-South - 10 SITE D SOUTH Weekly Level, Velocity and Flow Hydrographs 2/6/2023 to 2/13/2023 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 Mon Tue Wed Thu Fri Sat Sun Le v e l ( i n ) Lev 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 Ve l o c i t y ( f p s ) Vel 0.00 0.05 0.10 0.15 0.20 0.25 0.30 2/6 2/7 2/8 2/9 2/10 2/11 2/12 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 Ra i n ( i n / h r ) Rain Flow ADWFTotal Weekly Rainfall: 0.14 inches Avg Level: 3.13 in. Peak Level: 4.00 in. Min Level: 2.44 in. Avg Velocity: 0.78 fps Peak Velocity: 1.26 fps Min Velocity: 0.18 fps Avg Flow: 0.077 mgd Peak Flow: 0.147 mgd Min Flow: 0.012 mgd | Site D-South - 11 SITE D SOUTH Weekly Level, Velocity and Flow Hydrographs 2/13/2023 to 2/20/2023 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 Mon Tue Wed Thu Fri Sat Sun Le v e l ( i n ) Lev 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 Ve l o c i t y ( f p s ) Vel 0.00 0.05 0.10 0.15 0.20 0.25 0.30 2/13 2/14 2/15 2/16 2/17 2/18 2/19 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 Ra i n ( i n / h r ) Rain Flow ADWFTotal Weekly Rainfall: 0.03 inches Avg Level: 3.06 in. Peak Level: 4.00 in. Min Level: 2.35 in. Avg Velocity: 0.77 fps Peak Velocity: 1.37 fps Min Velocity: 0.21 fps Avg Flow: 0.073 mgd Peak Flow: 0.153 mgd Min Flow: 0.017 mgd | Site D-South - 12 SITE D SOUTH Weekly Level, Velocity and Flow Hydrographs 2/20/2023 to 2/27/2023 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 Mon Tue Wed Thu Fri Sat Sun Le v e l ( i n ) Lev 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 Ve l o c i t y ( f p s ) Vel 0.00 0.05 0.10 0.15 0.20 0.25 0.30 2/20 2/21 2/22 2/23 2/24 2/25 2/26 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 Ra i n ( i n / h r ) Rain Flow ADWFTotal Weekly Rainfall: 2.41 inches Avg Level: 3.24 in. Peak Level: 6.81 in. Min Level: 2.38 in. Avg Velocity: 0.71 fps Peak Velocity: 1.22 fps Min Velocity: 0.15 fps Avg Flow: 0.071 mgd Peak Flow: 0.141 mgd Min Flow: 0.014 mgd | Site D-South - 13 SITE D SOUTH Weekly Level, Velocity and Flow Hydrographs 2/27/2023 to 3/6/2023 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 Mon Tue Wed Thu Fri Sat Sun Le v e l ( i n ) Lev 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 Ve l o c i t y ( f p s ) Vel 0.00 0.05 0.10 0.15 0.20 0.25 0.30 2/27 2/28 3/1 3/2 3/3 3/4 3/5 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 Ra i n ( i n / h r ) Rain Flow ADWFTotal Weekly Rainfall: 0.88 inches Avg Level: 3.27 in. Peak Level: 4.25 in. Min Level: 2.50 in. Avg Velocity: 0.84 fps Peak Velocity: 1.31 fps Min Velocity: 0.33 fps Avg Flow: 0.087 mgd Peak Flow: 0.156 mgd Min Flow: 0.023 mgd | Site D-South - 14 SITE D SOUTH Weekly Level, Velocity and Flow Hydrographs 3/6/2023 to 3/13/2023 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 Mon Tue Wed Thu Fri Sat Sun Le v e l ( i n ) Lev 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 Ve l o c i t y ( f p s ) Vel 0.00 0.05 0.10 0.15 0.20 0.25 0.30 3/6 3/7 3/8 3/9 3/10 3/11 3/12 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 Ra i n ( i n / h r ) Rain Flow ADWFTotal Weekly Rainfall: 1.04 inches Avg Level: 3.34 in. Peak Level: 4.91 in. Min Level: 2.49 in. Avg Velocity: 0.80 fps Peak Velocity: 1.36 fps Min Velocity: 0.24 fps Avg Flow: 0.085 mgd Peak Flow: 0.187 mgd Min Flow: 0.022 mgd | Site D-South - 15 SITE D SOUTH Weekly Level, Velocity and Flow Hydrographs 3/13/2023 to 3/20/2023 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 Mon Tue Wed Thu Fri Sat Sun Le v e l ( i n ) Lev 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 Ve l o c i t y ( f p s ) Vel 0.00 0.05 0.10 0.15 0.20 0.25 0.30 3/13 3/14 3/15 3/16 3/17 3/18 3/19 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 Ra i n ( i n / h r ) Rain Flow ADWFTotal Weekly Rainfall: 2.79 inches Avg Level: 3.54 in. Peak Level: 6.16 in. Min Level: 2.62 in. Avg Velocity: 0.89 fps Peak Velocity: 1.44 fps Min Velocity: 0.34 fps Avg Flow: 0.100 mgd Peak Flow: 0.168 mgd Min Flow: 0.027 mgd | Site D-South - 16 SITE D SOUTH Weekly Level, Velocity and Flow Hydrographs 3/20/2023 to 3/27/2023 Appendix A Flow Monitoring Site Reports: Data, Graphs, Information 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 Mon Tue Wed Thu Fri Sat Sun Le v e l ( i n ) Lev 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 Ve l o c i t y ( f p s ) Vel 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 3/20 3/21 3/22 3/23 3/24 3/25 3/26 Fl o w ( m g d ) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 Ra i n ( i n / h r ) Rain Flow ADWFTotal Weekly Rainfall: 1.91 inches Avg Level: 3.82 in. Peak Level: 6.93 in. Min Level: 2.75 in. Avg Velocity: 0.93 fps Peak Velocity: 1.41 fps Min Velocity: 0.69 fps Avg Flow: 0.115 mgd Peak Flow: 0.305 mgd Min Flow: 0.054 mgd | Site D-South - 17 APPENDIX D HARDING STREET AND GRAND AVENUE RESIDENTIAL AND COMMERCIAL EDUs AND SEWER FLOW CALCULATION 300 ft N ➤➤ N Image © 2024 Airbus Image © 2024 Airbus Image © 2024 Airbus 1135-001 2/20/2024 Sewer Reach Street Commercial Building Space Sqft. 1 MF Residential Dus 2 EDUs Average Flow, gpd Peak Flow, gpd 5258 to 200 Harding Street 14,128 0 7.8 1,560 3,900 200 to 1068 Harding Street 23,193 7 18.5 3,700 9,250 1068 to 1060 Grand Avenue 14,753 38 38.6 7,720 19,300 TOTAL --52,074 45 64.9 12,980 32,450 1. 1 EDU/1,800 sqft 2. Multi-Family Residence = 0.8 EDU TABLE C-1 EXISTING AVERAGE SEWER FLOWS COMMERCIAL LOTS ALONG HARDING STREET AND GRAND AVENUE \\ARTIC\Eng\1135001\Sewer\Updated\2024-02-12 Carlsbad Village Harding and Grand Flows.xlsx APPENDIX E SEWER AS-BUILT DRAWINGS APPENDIX F EXISTING SEWER SYSTEM ANALYSIS UNDER EXISTING PEAK DRY WEATHER FLOW AND EXISTING PEAK WET WEATHER FLOW 2/12/2024 FOR:SHT 1 OF 1 1135-001 BY:REFER TO PLAN SHEET: M.G.D.C.F.S. 5259 6538 197,500 0 197,500 0.198 0.306 6 3.00 0.145640 0.19260 0.39 0.2789 4.38 6538 5258 197,500 0 197,500 0.198 0.306 6 2.80 0.150752 0.19623 0.39 0.2860 4.27 5258 200 382,500 3,900 386,400 0.386 0.598 10 0.28 0.238856 0.42483 0.51 0.4028 2.14 200 1068 382,500 13,150 395,650 0.396 0.612 10 0.28 0.244574 0.43081 0.52 0.4100 2.15 1068 1060 382,500 32,450 414,950 0.415 0.642 10 1.16 0.126022 0.29700 0.36 0.2511 3.68 1060 1061 607,000 110,450 717,450 0.717 1.110 12 2.89 0.084893 0.28999 0.29 0.1890 5.87 1061 1062 618,000 110,450 728,450 0.728 1.127 12 4.00 0.073265 0.26897 0.27 0.1702 6.62 Min Slope Max dn/D 0.28 0.52 A. Flows added to sewer flow monitoring data. To calculate EDUs, residential units and commercial building areas were used. Residential units were provided by the City. Building areas were obtained from SANGIS and converted to EDUs using 1 EDU/1,800 sqft. See Appendix D for detail. City Master Plan PDWF 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) City Master Plan PDWF 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) Sewer Flow Monitoring Data 7.8 EDUs added, see Appendix D 7.8 + 18.5 = 26.3 EDUs added, see Appendix D dn (feet)dn/D(2)Ca for Velocity(3)VELOCITY (f.p.s.) 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Sewer Flow Monitoring Data Existing Project Site Average Flow = 6,674 gpd (see Table 3 of report). Peak Flow = 6,674 gpd x 2.5 = 16,685 COMMENTS ALINE SIZE (inches) DATE:SEWER STUDY SUMMARY Carlsbad Village Mixed Use Project - Existing System, Existing PDWF JOB NUMBER:Dexter Wilson Engineering, Inc. LINE FROM TO EXISTING PEAK FLOW (gpd) PEAK FLOW (DESIGN FLOW)DESIGN SLOPE (%)DEPTH K' (1) ADDITIONAL EXISTING PEAK FLOW (gpd) A COMBINED PEAK FLOW (gpd) 1 K' based on n = 0.011 2 dn/D using K' in Brater King Table 7-14 3 From Brater King Table 7-4 based on dn/D \\ARTIC\Eng\1135001\Sewer\Updated\2024-02-20 Carlsbad Village Offsite Sewer Analysis_FlowMonitoring.xlsx Existing PDWF 2/12/2024 FOR:SHT 1 OF 1 1135-001 BY:REFER TO PLAN SHEET: M.G.D.C.F.S. 5259 6538 298,000 0 298,000 0.298 0.461 6 3.00 0.219751 0.24240 0.48 0.3775 4.89 6538 5258 298,000 0 298,000 0.298 0.461 6 2.80 0.227464 0.24723 0.49 0.3873 4.76 5258 200 610,350 3,900 614,250 0.614 0.950 10 0.28 0.379703 0.57465 0.69 0.5776 2.37 200 1068 615,450 13,150 628,600 0.629 0.973 10 0.28 0.388574 0.58402 0.70 0.5877 2.38 1068 1060 622,150 32,450 654,600 0.655 1.013 10 1.16 0.198804 0.38147 0.46 0.3505 4.16 1060 1061 1,214,000 110,450 1,324,450 1.324 2.049 12 2.89 0.156716 0.40086 0.40 0.2942 6.96 1061 1062 1,236,000 110,450 1,346,450 1.346 2.083 12 4.00 0.135422 0.37033 0.37 0.2645 7.88 Min Slope Max dn/D 0.28 0.70 A. The PWWF obtained from the sewer flow monitoring data pertain to the specific storm event monitored and, although not regarded as the design PWWF, demonstrate that the existing sewer in Carlsbad Village Drive does not meet the flow depth criterion under pre-project conditions (see Appendix C, Site D-East - 9). B. Flows added to sewer flow monitoring data. To calculate EDUs, residential units and commercial building areas were used. Residential units were provided by the City. Building areas were obtained from SANGIS and converted to EDUs using 1 EDU/1,800 sqft. See Appendix D for detail. ADDITIONAL EXISTING PEAK FLOW (gpd) B COMBINED PEAK FLOW (gpd)Ca for Velocity(3) DATE:SEWER STUDY SUMMARY Carlsbad Village Mixed Use Project - Existing System, Existing PWWF JOB NUMBER:Dexter Wilson Engineering, Inc. LINE FROM TO EXISTING PEAK FLOW (gpd) A PEAK FLOW (DESIGN FLOW)LINE SIZE (inches) DESIGN SLOPE (%)DEPTH K' (1)dn (feet)dn/D(2) 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D PDWF conservatively multiplied by 2 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) PDWF conservatively multiplied by 2 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) VELOCITY (f.p.s.)COMMENTS B Sewer Flow Monitoring Data Existing Project Site Average Flow = 6,674 gpd (see Table 3 of report). Peak Flow = 6,674 gpd x 2.5 = 16,685 Sewer Flow Monitoring Data 7.8 EDUs added, see Appendix D 7.8 + 18.5 = 26.3 EDUs added, see Appendix D 1 K' based on n = 0.011 2 dn/D using K' in Brater King Table 7-14 3 From Brater King Table 7-4 based on dn/D \\ARTIC\Eng\1135001\Sewer\Updated\2024-02-20 Carlsbad Village Offsite Sewer Analysis_FlowMonitoring.xlsx Existing PWWF APPENDIX G EXISTING SEWER SYSTEM ANALYSIS UNDER EXISTING PLUS PROJECT PEAK DRY WEATHER FLOW AND PEAK WET WEATHER FLOW 12/22/2023 FOR:SHT 1 OF 1 1135-001 BY:REFER TO PLAN SHEET: M.G.D.C.F.S. 5259 6538 180,815 0 0 180,815 0.181 0.280 6 3.00 0.133336 0.18363 0.37 0.2616 4.28 Sewer Flow Monitoring Data 6538 5258 180,815 0 91,033 271,848 0.272 0.421 6 2.80 0.207502 0.23455 0.47 0.3618 4.65 5258 200 365,815 3,900 91,033 460,748 0.461 0.713 10 0.28 0.284815 0.47272 0.57 0.4595 2.23 Sewer Flow Monitoring Data 7.8 EDUs added, see Appendix D 200 1068 365,815 13,150 91,033 469,998 0.470 0.727 10 0.28 0.290533 0.47868 0.57 0.4664 2.25 7.8 + 18.5 = 26.3 EDUs added, see Appendix D 1068 1060 365,815 32,450 91,033 489,298 0.489 0.757 10 1.16 0.148601 0.32453 0.39 0.2830 3.85 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D 1060 1061 590,315 110,450 91,033 791,798 0.792 1.225 12 2.89 0.093690 0.30507 0.31 0.2029 6.04 City Master Plan PDWF 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) 1061 1062 601,315 110,450 91,033 802,798 0.803 1.242 12 4.00 0.080743 0.28258 0.28 0.1823 6.81 City Master Plan PDWF 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) Min Slope Max dn/D 0.28 0.57 A. Existing peak flow of 16,685 gpd for the existing Carlsbad Village Mixed Use site is subtracted out downstream of Manhole 6538 due to proposed redevelopment (see Table 3 of report). B. Flows added to sewer flow monitoring data. To calculate EDUs, residential units and commercial building areas were used. Residential units were provided by the City. Building areas were obtained from SANGIS and converted to EDUs using 1 EDU/1,800 sqft. See Appendix D for detail. Dexter Wilson Engineering, Inc. SEWER STUDY SUMMARY COMMENTS B PEAK FLOW (DESIGN FLOW)LINE SIZE (inches) DESIGN SLOPE (%)DEPTH K' (1)dn (feet)dn/D(2)COMBINED PEAK FLOW (gpd) DATE: JOB NUMBER: LINE FROM TO EXISTING PEAK FLOW (gpd) A PROPOSED PROJECT PEAK FLOW (gpd) Ca for Velocity(3)VELOCITY (f.p.s.) ADDITIONAL EXISTING PEAK FLOW (gpd) B Carlsbad Village Mixed Use Project - Existing System, Existing + Project PDWF 1 K' based on n = 0.013 2 dn/D using K' in Brater King Table 7-14 3 From Brater King Table 7-4 based on dn/D \\ARTIC\Eng\1135001\Sewer\Updated\2024-02-20 Carlsbad Village Offsite Sewer Analysis_FlowMonitoring.xlsx Existing + Project PDWF 12/22/2023 FOR:SHT 1 OF 1 1135-001 BY:REFER TO PLAN SHEET: M.G.D.C.F.S. 5259 6538 281,315 0 0 281,315 0.281 0.435 6 3.00 0.207447 0.23451 0.47 0.3617 4.81 Sewer Flow Monitoring Data 6538 5258 281,315 0 91,033 372,348 0.372 0.576 6 2.80 0.284213 0.28326 0.57 0.4589 5.02 5258 200 593,665 3,900 91,033 688,598 0.689 1.065 10 0.28 0.425662 0.62936 0.76 0.6362 2.41 Sewer Flow Monitoring Data 7.8 EDUs added, see Appendix D 200 1068 598,765 13,150 91,033 702,948 0.703 1.088 10 0.28 0.434532 0.64102 0.77 0.6483 2.42 7.8 + 18.5 = 26.3 EDUs added, see Appendix D 1068 1060 605,465 32,450 91,033 728,948 0.729 1.128 10 1.16 0.221384 0.40575 0.49 0.3796 4.28 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D 1060 1061 1,197,315 110,450 91,033 1,398,798 1.399 2.164 12 2.89 0.165514 0.41307 0.41 0.3062 7.07 PDWF conservatively multiplied by 2 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) 1061 1062 1,219,315 110,450 91,033 1,420,798 1.421 2.198 12 4.00 0.142899 0.38128 0.38 0.2751 7.99 PDWF conservatively multiplied by 2 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) Min Slope Max dn/D 0.28 0.77 A. Existing peak flow of 20,000 gpd for existing Carlsbad Village Mixed Use site is subtracted out downstream of Manhole 6538 due to proposed redevelopment (see Table 3 of report). B. The PWWF obtained from the sewer flow monitoring data pertain to the specific storm event monitored and, although not regarded as the design PWWF, demonstrate that the existing sewer in Carlsbad Village Drive does not meet the flow depth criterion under pre-project conditions (see Appendix C, Site D-East - 9). C. Flows added to sewer flow monitoring data. To calculate EDUs, residential units and commercial building areas were used. Residential units were provided by the City. Building areas were obtained from SANGIS and converted to EDUs using 1 EDU/1,800 sqft. See Appendix D for detail. SEWER STUDY SUMMARY ADDITIONAL EXISTING PEAK FLOW (gpd) C COMBINED PEAK FLOW (gpd) DATE: JOB NUMBER: LINE FROM TO EXISTING PEAK FLOW (gpd) A,B PROPOSED PROJECT PEAK FLOW (gpd) Ca for Velocity(3)VELOCITY (f.p.s.) Carlsbad Village Mixed Use Project - Existing System, Existing + Project PWWF Dexter Wilson Engineering, Inc. COMMENTS C PEAK FLOW (DESIGN FLOW)LINE SIZE (inches) DESIGN SLOPE (%)DEPTH K' (1)dn (feet)dn/D(2) 1 K' based on n = 0.013 2 dn/D using K' in Brater King Table 7-14 3 From Brater King Table 7-4 based on dn/D \\ARTIC\Eng\1135001\Sewer\Updated\2024-02-20 Carlsbad Village Offsite Sewer Analysis_FlowMonitoring.xlsx Existing + Project PWWF APPENDIX H PROPOSED SEWER SYSTEM ANALYSIS UNDER EXISTING PLUS PROJECT PEAK DRY WEATHER FLOW AND PEAK WET WEATHER FLOW 12/22/2023 FOR:SHT 1 OF 1 1135-001 BY:REFER TO PLAN SHEET: M.G.D.C.F.S. 5259 6538 180,815 0 0 180,815 0.181 0.280 8 3.00 0.061913 0.16464 0.25 0.1509 4.17 Sewer Flow Monitoring Data 6538 5258 180,815 0 91,033 271,848 0.272 0.421 8 2.80 0.096350 0.20638 0.31 0.2070 4.57 5258 200 365,815 3,900 91,033 460,748 0.461 0.713 12 0.28 0.175151 0.42629 0.43 0.3192 2.23 Sewer Flow Monitoring Data 7.8 EDUs added, see Appendix D 200 1068 365,815 13,150 91,033 469,998 0.470 0.727 12 0.28 0.178667 0.43102 0.43 0.3239 2.25 7.8 + 18.5 = 26.3 EDUs added, see Appendix D 1068 1060 365,815 32,450 91,033 489,298 0.489 0.757 10 1.16 0.148601 0.32453 0.39 0.2830 3.85 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D 1060 1061 590,315 110,450 91,033 791,798 0.792 1.225 12 2.89 0.093690 0.30507 0.31 0.2029 6.04 City Master Plan PDWF 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) 1061 1062 601,315 110,450 91,033 802,798 0.803 1.242 12 4.00 0.080743 0.28258 0.28 0.1823 6.81 City Master Plan PDWF 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) Min Slope Max dn/D 0.28 0.43 A. Existing peak flow of 16,685 gpd for the existing Carlsbad Village Mixed Use site is subtracted out downstream of Manhole 6538 due to proposed redevelopment (see Table 3 of report). B. Flows added to sewer flow monitoring data. To calculate EDUs, residential units and commercial building areas were used. Residential units were provided by the City. Building areas were obtained from SANGIS and converted to EDUs using 1 EDU/1,800 sqft. See Appendix D for detail. dn/D(2)Ca for Velocity(3)VELOCITY (f.p.s.)COMMENTS BCOMBINED PEAK FLOW (gpd) PEAK FLOW (DESIGN FLOW)LINE SIZE (inches) DESIGN SLOPE (%)DEPTH K' (1)dn (feet)LINE FROM TO EXISTING PEAK FLOW (gpd) A ADDITIONAL EXISTING PEAK FLOW (gpd) B PROPOSED PROJECT PEAK FLOW (gpd) DATE:SEWER STUDY SUMMARY Carlsbad Village Mixed Use Project - Proposed System, Existing + Project PDWF JOB NUMBER:Dexter Wilson Engineering, Inc. 1 K' based on n = 0.013 2 dn/D using K' in Brater King Table 7-14 3 From Brater King Table 7-4 based on dn/D \\ARTIC\Eng\1135001\Sewer\Updated\2024-02-20 Carlsbad Village Offsite Sewer Analysis_FlowMonitoring.xlsx Existing + Project PDWF_PRO 12/22/2023 FOR:SHT 1 OF 1 1135-001 BY:REFER TO PLAN SHEET: M.G.D.C.F.S. 5259 6538 281,315 0 0 281,315 0.281 0.435 8 3.00 0.096325 0.20636 0.31 0.2070 4.73 Sewer Flow Monitoring Data 6538 5258 281,315 0 91,033 372,348 0.372 0.576 8 2.80 0.131970 0.24350 0.37 0.2596 4.99 5258 200 593,665 3,900 91,033 688,598 0.689 1.065 12 0.28 0.261767 0.53846 0.54 0.4315 2.47 Sewer Flow Monitoring Data 7.8 EDUs added, see Appendix D 200 1068 598,765 13,150 91,033 702,948 0.703 1.088 12 0.28 0.267222 0.54528 0.55 0.4383 2.48 7.8 + 18.5 = 26.3 EDUs added, see Appendix D 1068 1060 605,465 32,450 91,033 728,948 0.729 1.128 10 1.16 0.221384 0.40575 0.49 0.3796 4.28 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D 1060 1061 1,197,315 110,450 91,033 1,398,798 1.399 2.164 12 2.89 0.165514 0.41307 0.41 0.3062 7.07 PDWF conservatively multiplied by 2 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) 1061 1062 1,219,315 110,450 91,033 1,420,798 1.421 2.198 12 4.00 0.142899 0.38128 0.38 0.2751 7.99 PDWF conservatively multiplied by 2 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) Min Slope Max dn/D 0.28 0.55 A. Existing peak flow of 20,000 gpd for existing Carlsbad Village Mixed Use site is subtracted out downstream of Manhole 6538 due to proposed redevelopment (see Table 3 of report). B. The PWWF obtained from the sewer flow monitoring data pertain to the specific storm event monitored and, although not regarded as the design PWWF, demonstrate that the existing sewer in Carlsbad Village Drive does not meet the flow depth criterion under pre-project conditions (see Appendix C, Site D-East - 9). C. Flows added to sewer flow monitoring data. To calculate EDUs, residential units and commercial building areas were used. Residential units were provided by the City. Building areas were obtained from SANGIS and converted to EDUs using 1 EDU/1,800 sqft. See Appendix D for detail. dn/D(2)Ca for Velocity(3)VELOCITY (f.p.s.)COMMENTS CCOMBINED PEAK FLOW (gpd) PEAK FLOW (DESIGN FLOW)LINE SIZE (inches) DESIGN SLOPE (%)DEPTH K' (1)dn (feet)LINE FROM TO EXISTING PEAK FLOW (gpd) A,B ADDITIONAL EXISTING PEAK FLOW (gpd) C PROPOSED PROJECT PEAK FLOW (gpd) DATE:SEWER STUDY SUMMARY Carlsbad Village Mixed Use Project - Proposed System, Existing + Project PWWF JOB NUMBER:Dexter Wilson Engineering, Inc. 1 K' based on n = 0.013 2 dn/D using K' in Brater King Table 7-14 3 From Brater King Table 7-4 based on dn/D \\ARTIC\Eng\1135001\Sewer\Updated\2024-02-20 Carlsbad Village Offsite Sewer Analysis_FlowMonitoring.xlsx Existing + Project PWWF_PRO APPENDIX I EXISTING SEWER SYSTEM ANALYSIS UNDER MASTER PLAN PEAK DRY WEATHER FLOW AND PEAK WET WEATHER FLOW 12/22/2023 FOR:SHT 1 OF 1 1135-001 BY:REFER TO PLAN SHEET: M.G.D.C.F.S. 5259 6538 288,500 0 288,500 0.289 0.446 6 3.00 0.180015 0.21641 0.43 0.3257 5.48 6538 5258 288,500 0 288,500 0.289 0.446 6 2.80 0.186333 0.22062 0.44 0.3340 5.35 5258B 200 577,000 3,900 580,900 0.581 0.899 10 0.28 0.359088 0.55113 0.66 0.5512 2.35 200 1068 577,000 13,150 590,150 0.590 0.913 10 0.28 0.364806 0.55709 0.67 0.5577 2.36 1068 1060 577,000 32,450 609,450 0.609 0.943 10 1.16 0.185092 0.36632 0.44 0.3324 4.09 1060 1061 607,000 110,450 717,450 0.717 1.110 12 2.89 0.084893 0.28999 0.29 0.1890 5.87 1061 1062 618,000 110,450 728,450 0.728 1.127 12 4.00 0.073265 0.26897 0.27 0.1702 6.62 Min Slope Max dn/D 0.28 0.67 A. Flows added to sewer flow monitoring data. To calculate EDUs, residential units and commercial building areas were used. Residential units were provided by the City. Building areas were obtained from SANGIS and converted to EDUs using 1 EDU/1,800 sqft. See Appendix D for detail. City Master Plan PDWF 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) City Master Plan PDWF 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) City Master Plan PDWF 7.8 EDUs added, see Appendix D 7.8 + 18.5 = 26.3 EDUs added, see Appendix D dn (feet)dn/D(2)Ca for Velocity(3)VELOCITY (f.p.s.) 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D City Master Plan PDWF for Reach 5258 to 200 conservatively divided by 2 Existing Project Site Average Flow = 6,674 gpd (see Table 3 of report). Peak Flow = 6,674 gpd x 2.5 = 16,685 COMMENTS ALINE SIZE (inches) DATE:SEWER STUDY SUMMARY CVMU Project - Existing System, Existing PDWF (Master Plan) JOB NUMBER:Dexter Wilson Engineering, Inc. LINE FROM TO EXISTING PEAK FLOW (gpd) PEAK FLOW (DESIGN FLOW)DESIGN SLOPE (%)DEPTH K' (1) ADDITIONAL EXISTING PEAK FLOW (gpd) A COMBINED PEAK FLOW (gpd) 1 K' based on n = 0.013 2 dn/D using K' in Brater King Table 7-14 3 From Brater King Table 7-4 based on dn/D \\ARTIC\Eng\1135001\Sewer\Updated\2024-02-20 Carlsbad Village Offsite Sewer Analysis_CityModel.xlsx Existing PDWF 12/22/2023 FOR:SHT 1 OF 1 1135-001 BY:REFER TO PLAN SHEET: M.G.D.C.F.S. 5259 6538 409,500 0 409,500 0.410 0.634 6 3.00 0.255516 0.26532 0.53 0.4236 5.98 6538 5258 409,500 0 409,500 0.410 0.634 6 2.80 0.264484 0.27093 0.54 0.4349 5.83 5258B 200 819,000 3,900 822,900 0.823 1.273 10 0.28 0.508682 #N/A #N/A #N/A #N/A 200 1068 819,000 13,150 832,150 0.832 1.288 10 0.28 0.514400 #N/A #N/A #N/A #N/A 1068 1060 819,000 32,450 851,450 0.851 1.317 10 1.16 0.258588 0.44540 0.53 0.4275 4.44 1060 1061 1,214,000 110,450 1,324,450 1.324 2.049 12 2.89 0.156716 0.40086 0.40 0.2942 6.96 1061 1062 1,236,000 110,450 1,346,450 1.346 2.083 12 4.00 0.135422 0.37033 0.37 0.2645 7.88 Min Slope Max dn/D 0.28 #N/A A. Flows added to sewer flow monitoring data. To calculate EDUs, residential units and commercial building areas were used. Residential units were provided by the City. Building areas were obtained from SANGIS and converted to EDUs using 1 EDU/1,800 sqft. See Appendix D for detail. dn/D(2)LINE FROM TO EXISTING PEAK FLOW (gpd) PEAK FLOW (DESIGN FLOW) DATE:SEWER STUDY SUMMARY CVMU Project - Existing System, Existing PWWF (Master Plan) JOB NUMBER:Dexter Wilson Engineering, Inc. ADDITIONAL EXISTING PEAK FLOW (gpd) A COMBINED PEAK FLOW (gpd) 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D PDWF conservatively multiplied by 2 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) PDWF conservatively multiplied by 2 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) VELOCITY (f.p.s.)COMMENTS A City Master Plan PWWF for Reach 5258 to 200 conservatively divided by 2 Existing Project Site Average Flow = 6,674 gpd (see Table 3 of report). Peak Flow = 6,674 gpd x 2.5 = 16,685 City Master Plan PWWF 7.8 EDUs added, see Appendix D 7.8 + 18.5 = 26.3 EDUs added, see Appendix D Ca for Velocity(3)LINE SIZE (inches) DESIGN SLOPE (%)DEPTH K' (1)dn (feet) 1 K' based on n = 0.013 2 dn/D using K' in Brater King Table 7-14 3 From Brater King Table 7-4 based on dn/D \\ARTIC\Eng\1135001\Sewer\Updated\2024-02-20 Carlsbad Village Offsite Sewer Analysis_CityModel.xlsx Existing PWWF APPENDIX J EXISTING SEWER SYSTEM ANALYSIS UNDER MASTER PLAN PLUS PROJECT PEAK DRY WEATHER FLOW AND PEAK WET WEATHER FLOW 12/22/2023 FOR:SHT 1 OF 1 1135-001 BY:REFER TO PLAN SHEET: M.G.D.C.F.S. 5259 6538 271,815 0 0 271,815 0.272 0.421 6 3.00 0.169604 0.20938 0.42 0.3118 5.40 City Master Plan PDWF for Reach 5258 to 200 conservatively divided by 2 6538 5258 271,815 0 91,033 362,848 0.363 0.561 6 2.80 0.234353 0.25168 0.50 0.3964 5.67 5258 200 560,315 3,900 91,033 655,248 0.655 1.014 10 0.28 0.405046 0.60363 0.72 0.6089 2.40 City Master Plan PDWF 7.8 EDUs added, see Appendix D 200 1068 560,315 13,150 91,033 664,498 0.664 1.028 10 0.28 0.410764 0.61043 0.73 0.6163 2.40 7.8 + 18.5 = 26.3 EDUs added, see Appendix D 1068 1060 560,315 32,450 91,033 683,798 0.684 1.058 10 1.16 0.207671 0.39109 0.47 0.3620 4.21 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D 1060 1061 590,315 110,450 91,033 791,798 0.792 1.225 12 2.89 0.093690 0.30507 0.31 0.2029 6.04 City Master Plan PDWF 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) 1061 1062 601,315 110,450 91,033 802,798 0.803 1.242 12 4.00 0.080743 0.28258 0.28 0.1823 6.81 City Master Plan PDWF 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) Min Slope Max dn/D 0.28 0.73 A. Existing peak flow of 16,685 gpd for the existing Carlsbad Village Mixed Use site is subtracted out downstream of Manhole 6538 due to proposed redevelopment (see Table 3 of report). B. Flows added to sewer flow monitoring data. To calculate EDUs, residential units and commercial building areas were used. Residential units were provided by the City. Building areas were obtained from SANGIS and converted to EDUs using 1 EDU/1,800 sqft. See Appendix D for detail. Dexter Wilson Engineering, Inc. COMMENTS B PEAK FLOW (DESIGN FLOW)LINE SIZE (inches) DESIGN SLOPE (%)DEPTH K' (1)dn (feet)dn/D(2)COMBINED PEAK FLOW (gpd) DATE:SEWER STUDY SUMMARY JOB NUMBER: LINE FROM TO EXISTING PEAK FLOW (gpd) A PROPOSED PROJECT PEAK FLOW (gpd) Ca for Velocity(3)VELOCITY (f.p.s.) ADDITIONAL EXISTING PEAK FLOW (gpd) B CVMU Project - Existing System, Existing + Project PDWF (Master Plan) 1 K' based on n = 0.013 2 dn/D using K' in Brater King Table 7-14 3 From Brater King Table 7-4 based on dn/D \\ARTIC\Eng\1135001\Sewer\Updated\2024-02-20 Carlsbad Village Offsite Sewer Analysis_CityModel.xlsx Existing + Project PDWF 12/22/2023 FOR:SHT 1 OF 1 1135-001 BY:REFER TO PLAN SHEET: M.G.D.C.F.S. 5259 6538 392,815 0 0 392,815 0.393 0.608 6 3.00 0.245105 0.25882 0.52 0.4106 5.92 City Master Plan PWWF for Reach 5258 to 200 conservatively divided by 2 6538 5258 392,815 0 91,033 483,848 0.484 0.749 6 2.80 0.312503 0.30094 0.60 0.4939 6.06 5258 200 802,315 3,900 91,033 897,248 0.897 1.388 10 0.28 0.554640 #N/A #N/A #N/A #N/A City Master Plan PDWF 7.8 EDUs added, see Appendix D 200 1068 802,315 13,150 91,033 906,498 0.906 1.403 10 0.28 0.560358 #N/A #N/A #N/A #N/A 7.8 + 18.5 = 26.3 EDUs added, see Appendix D 1068 1060 802,315 32,450 91,033 925,798 0.926 1.433 10 1.16 0.281168 0.46892 0.56 0.4554 4.53 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D 1060 1061 1,197,315 110,450 91,033 1,398,798 1.399 2.164 12 2.89 0.165514 0.41307 0.41 0.3062 7.07 PDWF conservatively multiplied by 2 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) 1061 1062 1,219,315 110,450 91,033 1,420,798 1.421 2.198 12 4.00 0.142899 0.38128 0.38 0.2751 7.99 PDWF conservatively multiplied by 2 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) Min Slope Max dn/D 0.28 #N/A A. Existing peak flow of 20,000 gpd for existing Carlsbad Village Mixed Use site is subtracted out downstream of Manhole 6538 due to proposed redevelopment (see Table 3 of report). ADDITIONAL EXISTING PEAK FLOW (gpd) B COMBINED PEAK FLOW (gpd) DATE:SEWER STUDY SUMMARY JOB NUMBER: LINE FROM TO EXISTING PEAK FLOW (gpd) A PROPOSED PROJECT PEAK FLOW (gpd) Ca for Velocity(3)VELOCITY (f.p.s.) CVMU Project - Existing System, Existing + Project PWWF (Master Plan) Dexter Wilson Engineering, Inc. COMMENTS B PEAK FLOW (DESIGN FLOW)LINE SIZE (inches) DESIGN SLOPE (%)DEPTH K' (1)dn (feet)dn/D(2) 1 K' based on n = 0.013 2 dn/D using K' in Brater King Table 7-14 3 From Brater King Table 7-4 based on dn/D \\ARTIC\Eng\1135001\Sewer\Updated\2024-02-20 Carlsbad Village Offsite Sewer Analysis_CityModel.xlsx Existing + Project PWWF APPENDIX K PROPOSED SEWER SYSTEM ANALYSIS UNDER MASTER PLAN PLUS PROJECT PEAK DRY WEATHER FLOW AND PEAK WET WEATHER FLOW 12/22/2023 FOR:SHT 1 OF 1 1135-001 BY:REFER TO PLAN SHEET: M.G.D.C.F.S. 5259 6538 271,815 0 0 271,815 0.272 0.421 8 3.00 0.078753 0.18600 0.28 0.1791 5.28 City Master Plan PDWF for Reach 5258 to 200 conservatively divided by 2 6538 5258 271,815 0 91,033 362,848 0.363 0.561 8 2.80 0.108818 0.21991 0.33 0.2259 5.59 5258 200 560,315 3,900 91,033 655,248 0.655 1.014 12 0.28 0.249089 0.52261 0.52 0.4156 2.44 City Master Plan PDWF 7.8 EDUs added, see Appendix D 200 1068 560,315 13,150 91,033 664,498 0.664 1.028 12 0.28 0.252605 0.52701 0.53 0.4200 2.45 7.8 + 18.5 = 26.3 EDUs added, see Appendix D 1068 1060 560,315 32,450 91,033 683,798 0.684 1.058 10 1.16 0.207671 0.39109 0.47 0.3620 4.21 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D 1060 1061 590,315 110,450 91,033 791,798 0.792 1.225 12 2.89 0.093690 0.30507 0.31 0.2029 6.04 City Master Plan PDWF 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) 1061 1062 601,315 110,450 91,033 802,798 0.803 1.242 12 4.00 0.080743 0.28258 0.28 0.1823 6.81 City Master Plan PDWF 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) Min Slope Max dn/D 0.28 0.53 A. Existing peak flow of 16,685 gpd for the existing Carlsbad Village Mixed Use site is subtracted out downstream of Manhole 6538 due to proposed redevelopment (see Table 3 of report). B. Flows added to sewer flow monitoring data. To calculate EDUs, residential units and commercial building areas were used. Residential units were provided by the City. Building areas were obtained from SANGIS and converted to EDUs using 1 EDU/1,800 sqft. See Appendix D for detail. dn/D(2)Ca for Velocity(3)VELOCITY (f.p.s.)COMMENTS BCOMBINED PEAK FLOW (gpd) PEAK FLOW (DESIGN FLOW)LINE SIZE (inches) DESIGN SLOPE (%)DEPTH K' (1)dn (feet)LINE FROM TO EXISTING PEAK FLOW (gpd) A ADDITIONAL EXISTING PEAK FLOW (gpd) B PROPOSED PROJECT PEAK FLOW (gpd) DATE:SEWER STUDY SUMMARY CVMU Project - Proposed System, Existing + Project PDWF (Master Plan) JOB NUMBER:Dexter Wilson Engineering, Inc. 1 K' based on n = 0.013 2 dn/D using K' in Brater King Table 7-14 3 From Brater King Table 7-4 based on dn/D \\ARTIC\Eng\1135001\Sewer\Updated\2024-02-20 Carlsbad Village Offsite Sewer Analysis_CityModel.xlsx Existing + Project PDWF_PRO 12/22/2023 FOR:SHT 1 OF 1 1135-001 BY:REFER TO PLAN SHEET: M.G.D.C.F.S. 5259 6538 392,815 0 0 392,815 0.393 0.608 8 3.00 0.113810 0.22511 0.34 0.2333 5.86 City Master Plan PWWF for Reach 5258 to 200 conservatively divided by 2 6538 5258 392,815 0 91,033 483,848 0.484 0.749 8 2.80 0.145106 0.25629 0.38 0.2782 6.05 5258 200 802,315 3,900 91,033 897,248 0.897 1.388 12 0.28 0.341084 0.63761 0.64 0.5286 2.63 City Master Plan PDWF 7.8 EDUs added, see Appendix D 200 1068 802,315 13,150 91,033 906,498 0.906 1.403 12 0.28 0.344600 0.64229 0.64 0.5331 2.63 7.8 + 18.5 = 26.3 EDUs added, see Appendix D 1068 1060 802,315 32,450 91,033 925,798 0.926 1.433 10 1.16 0.281168 0.46892 0.56 0.4554 4.53 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D 1060 1061 1,197,315 110,450 91,033 1,398,798 1.399 2.164 12 2.89 0.165514 0.41307 0.41 0.3062 7.07 PDWF conservatively multiplied by 2 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) 1061 1062 1,219,315 110,450 91,033 1,420,798 1.421 2.198 12 4.00 0.142899 0.38128 0.38 0.2751 7.99 PDWF conservatively multiplied by 2 7.8 + 18.5 + 38.6 = 64.9 EDUs added, see Appendix D Hope Apts added (156 EDUs x 200 gpd/EDU x 2.5 = 78,000 gpd) Min Slope Max dn/D 0.28 0.64 A. Existing peak flow of 20,000 gpd for existing Carlsbad Village Mixed Use site is subtracted out downstream of Manhole 6538 due to proposed redevelopment (see Table 3 of report). dn/D(2)Ca for Velocity(3)VELOCITY (f.p.s.)COMMENTS BCOMBINED PEAK FLOW (gpd) PEAK FLOW (DESIGN FLOW)LINE SIZE (inches) DESIGN SLOPE (%)DEPTH K' (1)dn (feet)LINE FROM TO EXISTING PEAK FLOW (gpd) A ADDITIONAL EXISTING PEAK FLOW (gpd) B PROPOSED PROJECT PEAK FLOW (gpd) DATE:SEWER STUDY SUMMARY CVMU Project - Proposed System, Existing + Project PWWF (Master Plan) JOB NUMBER:Dexter Wilson Engineering, Inc. 1 K' based on n = 0.013 2 dn/D using K' in Brater King Table 7-14 3 From Brater King Table 7-4 based on dn/D \\ARTIC\Eng\1135001\Sewer\Updated\2024-02-20 Carlsbad Village Offsite Sewer Analysis_CityModel.xlsx Existing + Project PWWF_PRO EXHIBIT A MANHOLE DIAGRAM