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HomeMy WebLinkAboutAgenda Packet - Engineering & Operations Committee - 09/23/2024ENGINEERING & OPERATIONS COMMITTEE SEPTEMBER 23, 2024 East Valley Water District was formed in 1954 and provides water and wastewater services to 107,000 residents within the cities of San Bernardino and Highland, and portions of San Bernardino County. EVWD operates under the direction of a 5­member elected Board. COMMITTEE MEMBERS Phillip R. Goodrich Governing Board Member Chris Carrillo Governing Board Member Engineering & Operations Committee Meeting September 23, 2024 ­ 11:00 AM 31111 Greenspot Road, Highland, CA 92346 www.eastvalley.org PLEASE NOTE: Materials related to an item on this agenda submitted to the Board after distribution of the agenda packet are available for public inspection in the District’s office located at 31111 Greenspot Rd., Highland, during normal business hours. Also, such documents are available on the District’s website at eastvalley.org and are subject to staff’s ability to post the documents before the meeting. Pursuant to Government Code Section 54954.2(a), any request for a disability­related modification or accommodation, including auxiliary aids or services, that is sought in order to participate in the above agendized public meeting should be directed to the District Clerk at (909) 885­4900 at least 72 hours prior to said meeting. CALL TO ORDER PLEDGE OF ALLEGIANCE ROLL CALL OF BOARD MEMBERS PUBLIC COMMENTS Any person wishing to speak to the Board of Directors is asked to complete a Speaker Card and submit it to the District Clerk prior to the start of the meeting. Each speaker is limited to three (3) minutes, unless waived by the Chairman of the Board. Under the State of California Brown Act, the Board of Directors is prohibited from discussing or taking action on any item not listed on the posted agenda. The matter will automatically be referred to staff for an appropriate response or action and may appear on the agenda at a future meeting. APPROVAL OF CONSENT CALENDAR All matters listed under the Consent Calendar are considered by the Board of Directors to be routine and will be enacted in one motion. There will be no discussion of these items prior to the time the board considers the motion unless members of the board, the administrative staff, or the public request specific items to be discussed and/or removed from the Consent Calendar. 1.Consider approval of the May 28, 2024 Engineering and Operations Committee Meeting Minutes INFORMATIONAL ITEMS 2.Groundwater Levels Update 3.Sterling Natural Resource Center Food Waste Delivery Update REPORTS 4.Engineering Activities 5.Operations Activities ADJOURN ENGINEERING & OPERATIONS COMMITTEESEPTEMBER 23, 2024East Valley Water District was formed in 1954 and provides water and wastewater services to107,000 residents within the cities of San Bernardino and Highland, and portions of SanBernardino County.EVWD operates under the direction of a 5­member elected Board.COMMITTEE MEMBERS Phillip R. Goodrich Governing Board Member Chris Carrillo Governing Board Member Engineering & Operations Committee Meeting September 23, 2024 ­ 11:00 AM 31111 Greenspot Road, Highland, CA 92346 www.eastvalley.org PLEASE NOTE: Materials related to an item on this agenda submitted to the Board after distribution of the agenda packet are available for public inspection in the District’s office located at 31111 Greenspot Rd., Highland, during normal business hours. Also, such documents are available on the District’s website at eastvalley.org and are subject to staff’s ability to post the documents before the meeting. Pursuant to Government Code Section 54954.2(a), any request for a disability­related modification or accommodation, including auxiliary aids or services, that is sought in order to participate in the above agendized public meeting should be directed to the District Clerk at (909) 885­4900 at least 72 hours prior to said meeting. CALL TO ORDER PLEDGE OF ALLEGIANCE ROLL CALL OF BOARD MEMBERS PUBLIC COMMENTS Any person wishing to speak to the Board of Directors is asked to complete a Speaker Card and submit it to the District Clerk prior to the start of the meeting. Each speaker is limited to three (3) minutes, unless waived by the Chairman of the Board. Under the State of California Brown Act, the Board of Directors is prohibited from discussing or taking action on any item not listed on the posted agenda. The matter will automatically be referred to staff for an appropriate response or action and may appear on the agenda at a future meeting. APPROVAL OF CONSENT CALENDAR All matters listed under the Consent Calendar are considered by the Board of Directors to be routine and will be enacted in one motion. There will be no discussion of these items prior to the time the board considers the motion unless members of the board, the administrative staff, or the public request specific items to be discussed and/or removed from the Consent Calendar. 1.Consider approval of the May 28, 2024 Engineering and Operations Committee Meeting Minutes INFORMATIONAL ITEMS 2.Groundwater Levels Update 3.Sterling Natural Resource Center Food Waste Delivery Update REPORTS 4.Engineering Activities 5.Operations Activities ADJOURN ENGINEERING & OPERATIONS COMMITTEESEPTEMBER 23, 2024East Valley Water District was formed in 1954 and provides water and wastewater services to107,000 residents within the cities of San Bernardino and Highland, and portions of SanBernardino County.EVWD operates under the direction of a 5­member elected Board.COMMITTEE MEMBERSPhillip R. GoodrichGoverning Board Member Chris CarrilloGoverning Board MemberEngineering & Operations Committee MeetingSeptember 23, 2024 ­ 11:00 AM31111 Greenspot Road, Highland, CA 92346www.eastvalley.orgPLEASE NOTE:Materials related to an item on this agenda submitted to the Board after distribution of theagenda packet are available for public inspection in the District’s office located at 31111Greenspot Rd., Highland, during normal business hours. Also, such documents are availableon the District’s website at eastvalley.org and are subject to staff’s ability to post thedocuments before the meeting. Pursuant to Government Code Section 54954.2(a), any request for a disability­related modification or accommodation, including auxiliary aids or services, that is sought in order to participate in the above agendized public meeting should be directed to the District Clerk at (909) 885­4900 at least 72 hours prior to said meeting. CALL TO ORDER PLEDGE OF ALLEGIANCE ROLL CALL OF BOARD MEMBERS PUBLIC COMMENTS Any person wishing to speak to the Board of Directors is asked to complete a Speaker Card and submit it to the District Clerk prior to the start of the meeting. Each speaker is limited to three (3) minutes, unless waived by the Chairman of the Board. Under the State of California Brown Act, the Board of Directors is prohibited from discussing or taking action on any item not listed on the posted agenda. The matter will automatically be referred to staff for an appropriate response or action and may appear on the agenda at a future meeting. APPROVAL OF CONSENT CALENDAR All matters listed under the Consent Calendar are considered by the Board of Directors to be routine and will be enacted in one motion. There will be no discussion of these items prior to the time the board considers the motion unless members of the board, the administrative staff, or the public request specific items to be discussed and/or removed from the Consent Calendar. 1.Consider approval of the May 28, 2024 Engineering and Operations Committee Meeting Minutes INFORMATIONAL ITEMS 2.Groundwater Levels Update 3.Sterling Natural Resource Center Food Waste Delivery Update REPORTS 4.Engineering Activities 5.Operations Activities ADJOURN Agenda Item #1 September 23, 20241 Meeting Date: September 23, 2024 Agenda Item #1 Consent Item Regular Meeting TO: Committee Members FROM: Operations Manager SUBJECT: Consider approval of the May 28, 2024 Engineering and Operations Committee Meeting Minutes RECOMMENDATION That the Engineering & Operations Committee approve the May 28, 2024 meeting minutes. AGENCY GOALS AND OBJECTIVES II - Maintain a Commitment To Sustainability, Transparency, and Accountability B. Utilize Effective Communication Methods FISCAL IMPACT There is no fiscal impact associated with this agenda item. Respectfully submitted: ________________ Jeff Noelte Director of Engineering and Operations ATTACHMENTS Draft May 28, 2024 Engineering & Operations Committee Minutes P a g e | 1 Minutes 5/28/24 etb 9 1 2 Draft pending approval EAST VALLEY WATER DISTRICT May 28, 2024 ENGINEERING & OPERATIONS COMMITTEE MEETING MINUTES Ms. Bateman called the meeting to order at 1:30 p.m., Director Goodrich led the flag salute. PRESENT: Directors: Carrillo, Goodrich STAFF: Michael Moore, General Manager/CEO; Patrick Milroy, Operations Manager; Jason Wolf, Senior Engineer; Eileen Bateman, Human Resources Coordinator GUEST(s): Members of the Public and District Staff PUBLIC COMMENTS The Human Resources Coordinator declared the public participation section of the meeting open at 1:32 p.m. There being no written or verbal comments, the public participation section was closed. CONSIDER APPROVAL OF THE JANUARY 22, 2024, ENGINEERING AND OPERATIONS COMMITTEE MEETING MINUTES Director Goodrich recommended that the minutes be approved and due to the needs of necessity the minutes were approved. Operations Update Mr. Milroy provided an update on the Valve Replacement Program. He reviewed the process of replacing the valves throughout the District, explaining the need to replace the valves due to age and stated that 30 out of 40 valves have been replaced to date. Mr. Moore explained the cost benefits of replacing the valves rather than replacing the full pipelines. He provided detailed information regarding the use of a valve in the event of a main break. Mr. Milroy provided an update regarding Plant 120. He stated that after receiving an upgrade it is currently online and producing approximately 800 gallons per minute (GPM). Plant 134 is an option for water supply during the summer months if the need arises. P a g e | 2 Minutes 5/28/24 etb 9 1 2 Mr. Moore provided an update on future plans for the construction of new wells over the next decade to replace the two wells taken out of service due to the Sterling Natural Resource Center. Mr. Milroy reported information on the following: He explained the water recharging method for pumping out water from the Weaver Basin. He provided information regarding manhole pans and corks to help prevent rainwater inflow to the sewer system. He stated that the District participated in the Arroyo Valley High School Career Tour providing information regarding work experiences. Mr. Moore provided additional information regarding the sewer rainwater inflows and the effects of excess water on the biology in the Treatment plant and operations. Information only. Engineering Update Mr. Wolf provided a detailed overview of the repairs being made to the slope at Plant 56 and reservoir rehabilitation updates. Mr. Moore reported on Plant 52 tank updates to bring the reservoir up to code. He provided an update of plans to add a second tank on the site moving forward for continued service at the plant site. Information only. Set the Day and Time for Holding Recurring Meetings The Committee agreed to meet at 11:00 a.m. on the fourth Monday of odd numbered months. Engineering Activities Report Mr. Moore reported that staff is prioritizing grant funded projects such as seismic upgrades of the tanks and pipelines. The pipeline design upgrades are in the approval phase with FEMA and will move forward to the construction phase upon approval. He reported that Mr. Carlson is currently working on wells in the summer readiness program for drill fitting and explained the process of well preparation and staff evolvement. Information only. Operations Activities Report Mr. Milroy reported on Operations activities: He reported on the leak repair project planning stage. He stated that the Operations Department will be hiring a new Storekeeper/Buyer employee and provide training in June. He explained that the North Fork/Plunge Creek pipeline is planned for inspection to determine if updates are necessary. Information only. P a g e | 3 Minutes 5/28/24 etb 9 1 2 ADJOURN The meeting was adjourned at 2:51 p.m. Phillip R. Goodrich Chris Carrillo Governing Board Member Governing Board Member Agenda Item #2 September 23, 20241 Meeting Date: September 23, 2024 Agenda Item #2 Informational Item 1 7 7 5 Regular Meeting TO: Committee Members FROM: Operations Manager SUBJECT: Groundwater Levels Update RECOMMENDATION This agenda item is for informational purposes only, no action is required. BACKGROUND/ANALYSIS The Bunker Hill Basin stores water from the local mountains and imported water from the State Water Project. The Basin has a capacity of approximately 5.7 million acre-feet (MAF). Groundwater levels fluctuate depending on hydrologic conditions and pumping activities. Changes in groundwater levels can affect District groundwater wells. The District measures groundwater levels monthly to ensure wells are able to supply water to the distribution system. Regional water agencies collect water level measurements from most of the groundwater pumpers to determine the overall health of the Basin. The regional water agencies publish reports each year indicating the change in storage of the basin. The 2024 Engineering Investigation by San Bernardino Valley Water Conservation District is attached and indicates the steady increase in water levels throughout the basin. The District measures 12 active wells and 20 inactive wells in the District’s service area to achieve a full understating of the groundwater basin. Only a static water level can be recorded on inactive wells, but a measurement of both a static water level and a pumping water level can be recorded on active wells. When a well is pumping, it is common for the static level to drop; this is known as drawdown and provides information on the well performance. Local precipitation and runoff from the mountains have been higher than normal over the past year. The increase in Basin water storage between Fall 2022 and Fall 2023 is 0.22 MAF and has raised groundwater levels across the basin. The water levels were at historic low levels and remain low due to several years of dry weather. District wells are seeing a recovery in water levels since 2022. The groundwater supply is sustainable, and the District is closely monitoring storage levels to ensure the long-term health of the Basin. Agenda Item #2 September 23, 20242 Meeting Date: September 23, 2024 Agenda Item #2 Informational Item 1 7 7 5 AGENCY GOALS AND OBJECTIVES IV - Promote Planning, Maintenance and Preservation of District Resources B. Enhance Planning Efforts that Respond to Future Demands C. Dedicate Efforts Toward System Maintenance and Modernization FISCAL IMPACT There is no fiscal impact associated with this agenda item. Respectfully submitted: ________________ Patrick Milroy Operations Manager ATTACHMENTS Groundwater Level Presentation SBVWCD Engineering Investigation of Bunker Hill Basin Patrick Milroy, Operations Manager September 23, 2024 GROUNDWATER LEVELS 2 •12 Active wells •Depth range from 75 feet to 350 feet •Wells produce a range from 500 gallons per minute (gpm) to 2,500 gpm DISTRICT WELLS Plant 33 3 EVWD WATER SUPPLY 20% Surface Water 80% Groundwater 4 WELL MEASUREMENTS •Wells are sounded monthly and observed for changes •Wells are designed to pump from a specific water level •Changes in water level affect well performance 5 •Active wells are measured at static and pumping •Drawdown is the amount the water level drops while pumping •Some wells are impacted more severely than others •Water level drops can cause wells to draw air and be abandoned WELL MEASUREMENTS 6 PLANT 143 STATIC WATER LEVELS -250 -200 -150 -100 -50 0 7 PLANT 146A STATIC WATER LEVELS -600 -500 -400 -300 -200 -100 0 8 ANNUAL CHANGE IN GROUNDWATER Source: SBVMWD Change in Storage Report Legend Historic Low Spreading Basin Production Well 9 10 ANNUAL CHANGE IN GROUNDWATER San Bernardino Basin •Usable storage 5,690,000 AF •2023 Change in storage 222,760 AF •2023 Total storage 4,881,235 AF •Percentage Full: 86% •Change from 2022: 3.9% QUESTIONS www.sbvwcd.org Final Engineering Investigation of the Bunker Hill Basin 2022–2023 Prepared By: San Bernardino Valley Water Conservation District March 4, 2024 SBV Water Conservation District i Bunker Hill Basin 2024 Engineering Investigation Table of Contents 1.0 Executive Summary ........................................................................................................... 1 1.1 Summary of Finding for the 2024 Engineering Investigation .......................................... 3 2.0 Introduction ........................................................................................................................ 8 2.1 Purpose and Scope ........................................................................................................ 8 2.2 Location, Topography and Climate ............................................................................... 10 2.3 Definition of Terms ....................................................................................................... 11 2.4 Sources and Data ......................................................................................................... 11 3.0 Fall 2022 and Fall 2023 Groundwater Elevation Contours .............................................. 13 4.0 Task 1 – Annual Change in Storage (Fall 2022 to Fall 2023) .......................................... 14 4.1 Hydrologic Sub-areas ................................................................................................... 14 4.2 Area and Storativity ...................................................................................................... 14 4.3 Groundwater Level Elevation Changes ........................................................................ 14 4.4 Changes in Groundwater Storage ................................................................................ 15 5.0 Task 2 – Accumulated Change in Storage from Fall 1993 to Fall 2023 ........................... 16 6.0 Task 3 - Total Groundwater Production for the Preceding Water Year (July 1, 2022 to June 30, 2023) ..................................................................................................................................... 17 7.0 Task 4 - Estimate of the Annual Change in Storage for the Current Water Year (July 1, 2023 to June 30, 2024) ............................................................................................................... 18 8.0 Task 5 - Estimate of the Annual Change in Storage for the Ensuing Water Year (July 1, 2024 to June 30, 2025) ............................................................................................................... 20 9.0 Task 6 - Average Annual Change in Storage for the Immediate Past 10 Water Years .... 20 10.0 Task 7 - Estimated Amount of Historically Agricultural Water and Other Than Agricultural Water to be Withdrawn for the Ensuing Water Year (July 1, 2024 to June 30, 2025) ................ 20 11.0 Task 8 – Estimated Amount of Water for Surface Distribution for the Ensuing Water Year (July 1, 2024 to June 30, 2025) .................................................................................................. 23 12.0 Task 9 - Estimated Amount of Water for Replenishment of the Groundwater Supplies for the Ensuing Water Year (July 1, 2024 to June 30, 2025) ........................................................... 24 13.0 Quality Assurance and Quality Control ............................................................................ 25 13.1 Process and Method ..................................................................................................... 25 13.2 Data Accuracy .............................................................................................................. 25 SBV Water Conservation District ii Bunker Hill Basin 2024 Engineering Investigation 13.3 Calculation Accuracy .................................................................................................... 26 13.4 Comparability ................................................................................................................ 26 13.5 Approval ....................................................................................................................... 27 13.6 Improvements and Changes to the Report ................................................................... 27 14.0 General Findings .............................................................................................................. 28 15.0 Conclusions ...................................................................................................................... 28 16.0 Financial Data .................................................................................................................. 29 Figures Figure 1: Bunker Hill Basin Watershed Map Figure 2: Conservation District and Water Agency Boundaries Figure 3: Sub-areas of Bunker Hill Basin Figure 4: Precipitation Trends and Gauge Station Locations Figure 5: Fall 2022 Water Level Groundwater Contours Figure 6: Fall 2023 Water Level Groundwater Contours Figure 7: Locations of Key Wells with Hydrographs Figure 8: Groundwater Production in the Bunker Hill Basin Figure 9: Prediction Chart for Annual Change in Storage Figure 10: Estimate of Production for Current Water Year Figure 11: Estimate of Production for Ensuing Water Year SBV Water Conservation District iii Bunker Hill Basin 2024 Engineering Investigation Tables Table 1: Summary of Percentage of Normal Precipitation Table 2: Change in Groundwater Levels in Key Wells Table 3: Annual Change in Storage for the Bunker Hill Basin Table 4: Accumulated Change in Storage for Bunker Hill Basin (1989 to 2023) Table 5: Production for Sub-basins of Bunker Hill Basin Table 6: Estimates of Percentage of Normal Precipitation for Current Water Year Table 7: Average Annual Change in Storage for the Bunker Hill Basin Table 8: Summary of Surface Distribution Water for the Bunker Hill Basin Appendices Appendix A: Water Level Elevations for the Bunker Hill Basin Appendix B: Hydrographs for Key Wells Appendix C: Production Data for the Preceding Water Year Appendix D: Historic Annual Precipitation Appendix E: State Supreme Court Ruling Impact on Groundwater Charge All figures, tables, and appendices are available separately on San Bernardino Valley Water Conservation District’s Website: http://www.sbvwcd.org and incorporated by reference. SBV Water Conservation District 1 Bunker Hill Basin 2024 Engineering Investigation 1.0 Executive Summary Article 1, Section 75560 of the California Water Code requires that a Water Conservation District that proposes to levy a groundwater charge “… shall annually cause to be made an engineering investigation and report upon groundwater conditions of the District”. In accordance with these requirements, the San Bernardino Valley Water Conservation District (District) must make the following findings and determinations as they relate to the ground and surface water conditions of the Bunker Hill Basin and those areas within the District boundary. Refer to Figure 1 and 3 for locations. Task 1. Annual change in storage for the Bunker Hill Basin for the preceding water year (Fall 2022 to Fall 2023) Task 2. Accumulated change in storage of the Bunker Hill Basin as of the last day of the preceding water year (June 30, 2023) Task 3. Total groundwater production from the Bunker Hill Basin for the preceding water year (July 1, 2022 - June 30, 2023) Task 4. Estimate of the annual change in the Bunker Hill Basin storage for the current water year (July 1, 2023 - June 30, 2024) Task 5. Estimate of the annual change in the Bunker Hill Basin storage for the ensuing water year (July 1, 2024 - June 30, 2025) Task 6. Average annual change in Bunker Hill Basin storage for the immediate past ten water years (2013 - 2023) Task 7. Estimated amount of historically agricultural water and other than agricultural water to be withdrawn from the groundwater supplies of the District for the ensuing water year (July 1, 2024 - June 30, 2025) Task 8. Estimated amount of water necessary for surface distribution for the ensuing water year for the Bunker Hill Basin and the District (July 1, 2024 - June 30, 2025) Task 9. The amount of water that is necessary for the replenishment of the groundwater supplies of the Bunker Hill Basin and the District for the ensuing water year (July 1, 2024 - June 30, 2025) To make the findings and determinations listed above, District staff researched available hydro- geologic and engineering data for the Bunker Hill Basin. The data was compiled and analyzed and a predictive relationship between precipitation, production, and change in basin storage was SBV Water Conservation District 2 Bunker Hill Basin 2024 Engineering Investigation developed. This relationship was based on empirical data since 1993 and enables the prediction of change in storage given certain annual production and precipitation levels. In addition, annual and accumulated change in storage values were calculated based on current and historic water level changes throughout the Bunker Hill Basin. Based on 20 measuring stations, precipitation throughout the contributing watershed was 162.7% of normal for the period July 1, 2022 to June 31, 2023. The report uses production and water level data from more than 230 wells in the basin. The required findings for the 2024 Engineering Investigation are provided below. Each of the tasks is further explained in the main body of the report. Throughout this document a positive sign (+) denotes an increase in groundwater storage or groundwater level elevation while a negative sign (-) denotes a decrease in groundwater storage or groundwater level elevation. Section 75574 of the California Water Code requires that the District Board indicate the amount of water the District is obligated by contract to purchase. The San Bernardino Valley Water Conservation District is not required by contract to purchase any water. SBV Water Conservation District 3 Bunker Hill Basin 2024 Engineering Investigation 1.1 Summary of Finding for the 2024 Engineering Investigation Task 1. Annual change in storage for the Bunker Hill Basin for the preceding water year (Fall 2022 to Fall 2023): 226,806 acre-ft (increase) Task 2. Accumulated change in storage of the Bunker Hill Basin as of the last day of the preceding water year (July 1993 and June 20231): -424,456 acre-ft (decrease) Task 3. Total groundwater production from the Bunker Hill Basin for the preceding water year (July 1, 2022 - June 30, 2023): 139,296 acre-ft Task 4. Estimate of the annual change in the Bunker Hill Basin storage for the current water year (July 1, 2023 - June 30, 2024): 108,401 acre-ft (increase) 1 In the District’s Engineering Investigation (EI) prior to 1993-94, the accumulated change in storage was based on the basin storage in 1984 as considered full. A concern arose regarding high groundwater levels in the Pressure Zone of the Bunker Hill Basin. Therefore, in response to the City of San Bernardino’s comments on accumulated change in storage, all EI’s since that time are based on 1993 basin storage levels considered as full. The BTAC makes annual recharge recommendations to optimize recharge. The amount of water stored in the Basin increased by 226,806 acre-ft between 2022 and 2023. The amount in storage in the Summer of 2022 is 424,456 acre-ft less than the summer of 1993. 139,296 acre-ft of groundwater was produced from the basin during the previous water year. The amount of water in the Basin is estimated to increase by 108,401 acre-ft during the current water year. SBV Water Conservation District 4 Bunker Hill Basin 2024 Engineering Investigation Task 5. Estimate of the annual change in the Bunker Hill Basin storage for the ensuing water year (July 1, 2024 - June 30, 2025): -3,007 acre-ft (decrease) Task 6. Average annual change in Bunker Hill Basin storage for the immediate past ten water years (2013 - 2023): -1,238 acre-ft (decrease) Task 7. Estimated amount of historically2 agricultural water and other than agricultural water to be withdrawn from the groundwater supplies of the District for the ensuing water year (July 1, 2024 - June 30, 2025) Task 8. Estimated amount of water necessary for surface distribution for the ensuing water year for the Bunker Hill Basin and the District (July 1, 2024 - June 30, 2025) 2 Prior to the December 2017 California Supreme Court Decision the Board Provided an Agricultural rate in accordance with CWC 755. See Appendix E. The amount of water in the Basin is estimated to decrease by 3,007 acre-ft during the ensuing water year presuming average precipitation.  Estimated amount of historically agricultural water withdrawn from the groundwater supplies within the District boundary for the ensuing water year (July 1, 2024 - June 30, 2025): 5,021 acre-ft  Estimated amount of other than agricultural water withdrawn from the groundwater supplies of the District for the ensuing water year (July 1, 2024 - June 30, 2025): 94,101 acre-ft  Estimated amount of water necessary for surface distribution for the ensuing water year (July 1, 2024 - June 30, 2025) for the Bunker Hill Basin: 73,935 acre-ft  Estimated amount of water necessary for surface distribution for the ensuing water year (July 1, 2024 - June 30, 2025) within the District Boundary: 52,127 acre-ft SBV Water Conservation District 5 Bunker Hill Basin 2024 Engineering Investigation Task 9. The amount of water that is necessary for the replenishment of the groundwater supplies of the Bunker Hill Basin and the District for the ensuing water year (July 1, 2024 - June 30, 2025). In addition to the above findings, Section 75505 of the California Water Code requires that a finding be made as to the amount of water necessary to be replaced in the intake areas of the groundwater basins within the District to prevent the landward movement of salt water into the fresh groundwater body, or to prevent subsidence of the land within the District. Because of its location and the elevations of its water table, the Bunker Hill Basin is not subject to salt-water intrusion and the current groundwater levels do not indicate any significant land subsidence. Section 75540 of the California Water Code requires that the District Board establish a zone or zones where a groundwater charge is to be implemented. The Code specifically states that a single zone may include the entire District and in May 1993 the Board established the entire District as one zone. This determination may be amended in the future, but lacking any evidence to the contrary, in the 2023-2024 year the entire District will remain as a single zone in regard to any groundwater charge. Section 75561 of the California Water Code further requires the Engineering Investigation to include a finding related to the amount of water the District is obligated by contract to purchase. At this time the District has no contractual obligation to purchase water for the replenishment of the groundwater supplies. However, instead we recharge local surface water and cooperate with local and regional agencies to recharge the aquifer. The District works with San Bernardino Valley Municipal Water District (SBVMWD) to spread excess allocation State Project Water and Groundwater Council water in the District’s spreading basins. During 2023 approximately 30,000 acre-feet of State Project Water was spread across the Bunker Hill Basin due to its availability.  The amount of water which is necessary for the replenishment of the groundwater supplies of the Bunker Hill Basin for the ensuing water year (July 1, 2024 - June 30, 2025): 126,251 acre-ft  The amount of water which is necessary for the replenishment of the groundwater supplies within the District boundary for the ensuing water year (July 1, 2024 - June 30, 2025): 102,129 acre-ft SBV Water Conservation District 6 Bunker Hill Basin 2024 Engineering Investigation Based on the results of the 2024 Engineering Investigation, the San Bernardino Valley Water Conservation District finds that:  Due to the imbalance between groundwater recharge and production since 1993, the Bunker Hill Basin’s storage is 424,456 acre-feet below the level which is considered full for purposes of this investigation. This value is less than the 2023 report due to the increased availability of native and State Water Project water for recharge.  During the ensuing water year (July 1, 2024 - June 30, 2025), the Bunker Hill Basin could be recharged, with up to 442,307 acre-feet of water. This recharge quantity would be needed to attain the 1993 storage level that is considered full. The Basin Technical Advisory Committee (BTAC) recommends a maximum of 114,000 acre-ft in Mill Creek and Santa Ana River Basins.  The District must continue to take all necessary steps to maintain and enhance its capability to conduct recharge operations. These steps may include maintenance and repair of existing, diversion facilities, canals, dikes, basins, roads, and other water recharge facilities. Additionally in December 2011 the District entered into a cooperative agreement with SBVMWD to enhance the recharge of the basin. This project will add significant new recharge facilities in the District’s Santa Ana River Recharge Facilities. These facilities will be operated and maintained by the District. These improvements are required to ensure that the groundwater demands on the Basin, especially during drought periods, can be met. Construction for Phase 1A of the Enhanced Recharge Project is complete and construction of Phase 1B is began in 2023 and is expected to be complete in 2025.  The District should continue to work cooperatively in the collaborative planning for the Enhanced Recharge Program to plan, design, build and maintain facilities to expand the capabilities for recharge of native and imported waters.  The District has begun collaborative construction efforts with SBVMWD to improve the capacities and delivery capabilities of the District’s Upper Santa Ana River diverted water conveyance canals and spreading basins. The District should review the single zone of influence/benefit in the future and revise, if needed.  In 2015 the District Board of Directors approved an Engineering design to improve the sediment handling capabilities of the Mill Creek Diversion Structure. The structure was constructed in 2023 and is now in operation.  The District approved a Groundwater Council Framework Agreement in February of 2018. The agencies within the Bunker Hill basin have agreed on a cost allocation model for the SBV Water Conservation District 7 Bunker Hill Basin 2024 Engineering Investigation importation of additional State Project water when it is available through the council. The Groundwater Charge will be paid alternatively through this agreement for those agencies that have joined the Groundwater Council. SBV Water Conservation District 8 Bunker Hill Basin 2024 Engineering Investigation 2.0 Introduction The 2022-2023 Engineering Investigation (EI) process was very similar to the previous 2021-2022 EI Report. The report uses the same basis of calculation; however, updates to the document as proposed in the work plan prepared and approved in November 2023 have been incorporated. This approach also includes close coordination with other groups particularly San Bernardino Valley Municipal Water District (SBVMWD) who do their own calculations for work similar to the EI Report. We believe this approach makes the best use of the resources of all water entities within the basin. This year’s report provides additional research, source documentation, and summary illustration of surface and groundwater activities within the Bunker Hill Basin and specifically within the Water Conservation District’s boundaries. 2.1 Purpose and Scope The San Bernardino Valley Water Conservation District (District) was created by a vote of the people in 1931 for the purpose of managing the recharge activities that were previously conducted by the Water Conservation Association. The Water Conservation Association was incorporated in 1909 and had been diverting flows from the Santa Ana River for groundwater recharge since 1911. Currently the District has ownership, as well as easements and/or use of properties owned by the Bureau of Land Management (BLM), on a total of 3,735 acres within the Santa Ana River and Mill Creek Wash areas. The District boundary covers an area of approximately 50,000 acres, which represents about 60% of the Bunker Hill Basin. Figure 1 displays the project area map for the Engineering Investigation. The figure shows the District boundary along with its location relative to the County and State boundaries. Figure 2 shows the District Boundaries relative to the water agencies served by the District. Article 1, Section 75560 of the California Water Code requires that a Water Conservation District that proposes to levy a groundwater charge “… shall annually cause to be made an engineering investigation and report upon groundwater conditions of the District”. In accordance with these requirements, the San Bernardino Valley Water Conservation District (District) must make the following findings and determinations as they relate to the ground and surface water conditions of the Bunker Hill Basin and those areas within the District boundary. Sub-Basins of the Bunker Hill Basin are shown in Figure 3. SBV Water Conservation District 9 Bunker Hill Basin 2024 Engineering Investigation Task 1. Annual change in storage for the Bunker Hill Basin for the preceding water year (Fall 2022 to Fall 2023); Task 2. Accumulated change in storage of the Bunker Hill Basin as of the last day of the preceding water year (June 30, 2023); Task 3. Total groundwater production from the Bunker Hill Basin for the preceding water year (July 1, 2022 - June 30, 2023); Task 4. Estimate of the annual change in the Bunker Hill Basin storage for the current water year (July 1, 2023 - June 30, 2024); Task 5. Estimate of the annual change in the Bunker Hill Basin storage for the ensuing water year (July 1, 2024 - June 30, 2025) Task 6. Average annual change in Bunker Hill Basin storage for the immediate past ten water years (2013 - 2023); Task 7. Estimated amount of historically agricultural water and other than agricultural water to be withdrawn from the groundwater supplies of the District for the ensuing water year (July 1, 2024 - June 30, 2025) Task 8. Estimated amount of water necessary for surface distribution for the ensuing water year for the Bunker Hill Basin and the District (July 1, 2024 - June 30, 2025); and Task 9. The amount of water that is necessary for the replenishment of the groundwater supplies of the Bunker Hill Basin and the District for the ensuing water year (July 1, 2024 - June 30, 2025). To make the findings and determinations listed above, District staff researched available hydrogeologic, precipitation, and engineering data for the Bunker Hill Basin and surrounding areas. These data were compiled and analyzed and a predictive relationship between precipitation, production, and change in basin storage was adapted from similar relationships developed by Geoscience Support Services in the preparation of previous Engineering Investigations. This relationship was based on empirical data enables the prediction of change in storage, given certain annual production and precipitation levels. Precipitation trends and stations are shown in Figure 4. In addition, annual and accumulated change in storage was calculated based on historic water level changes throughout the Bunker Hill Basin. All calculations are rounded to the nearest whole number. SBV Water Conservation District 10 Bunker Hill Basin 2024 Engineering Investigation 2.2 Location, Topography and Climate The Bunker Hill Basin is located at the top of the Santa Ana River Watershed and receives all the surface water runoff from the headwaters of the Santa Ana River, Mill Creek, and a portion of that from the Lytle Creek area as well as smaller periodic flows from Plunge, City, Devil Canyon, Cajon and Elder Creeks. It is part of the inland valley called the San Bernardino Valley located in San Bernardino County, California and encompasses approximately 89,600 acres. Once past the Bunker Hill Basin, the Santa Ana River continues to flow southwesterly for approximately 60 miles until it reaches the Pacific Ocean. The Bunker Hill Basin is bounded on the northwest by the San Gabriel Mountains, on the northeast by the San Bernardino Mountains, on the south by the Crafton Hills and the Badlands, and on the southwest by a low east-facing escarpment produced by the San Jacinto fault. These geologic features are easily identified on Figure 5 and Figure 6. The major streams providing inflows and outflows for the Bunker Hill Basin are provided on Figure 1. The United States Geological Survey (USGS) administers stream flow gauging stations on all of these waterways except Mill Creek. Mill Creek flow is assumed to be 56% of the Santa Ana River flow in this location based on historic data. Total diversions for direct use and recharge on the Santa Ana River may exceed the stream flows due to measurements by different agencies. The Bunker Hill Basin is also utilized by a large group of City and Water Agencies that are working to collaborate for improved transparency. Figure 2 presents an overview of the Water Agency Jurisdictions with an overlay of City boundaries. The climate in the region is a semi-arid Mediterranean-type characterized by long dry summers and relatively short mild winters. The annual average temperature in the valley is 62° F, with extremes ranging from as low as 18°F to as high as 116°F (Burnham and Dutcher, 1960). Precipitation in the region is highly variable depending on location and elevation. Historical annual averages range from 10.97 inches near Loma Linda Fire Department located at the southwest end of the basin to over 37.34 inches at the Lake Arrowhead located at the upper end of the mountain watershed contributing flow to the basin. Precipitation data provided by the San Bernardino County Department of Transportation and Flood Control Water Resources Division for 20 stations are summarized in Table 1 and displayed on Figure 4. SBV Water Conservation District 11 Bunker Hill Basin 2024 Engineering Investigation 2.3 Definition of Terms For the purposes of this report, the following terms are defined:  Bunker Hill Basin – The Bunker Hill Basin is the groundwater basin that underlies the San Bernardino Valley. By strict definition according to (Dutcher and Garrett, 1963), the Bunker Hill Basin is separate from the Lytle Groundwater Basin, but receives groundwater underflow from the Lytle Basin. However, for completeness, the definition of the Bunker Hill Basin is extended to include the Lytle Basin for the purposes of this report.  Production – The term production includes extraction of water by groundwater pumping from wells and surface diversions from the Santa Ana River, Mill Creek, City Creek, Devil Canyon Creek, Cajon Creek, Plunge Creek, and Lytle Creek.  Preceding Water Year – As per the California Water Code, the preceding water year is the period July 1, 2022 through June 30, 2023.  Current Water Year – As per the California Water Code, the current water year is the period July 1, 2023 through June 30, 2024.  Ensuing Water Year – As per the California Water Code, the ensuing water year is the period July 1, 2024 through June 30, 2025. 2.4 Sources and Data Data used in the development of this engineering investigation were obtained from a variety of sources including public and private agencies. The data analysis tasks involved tabulating and summarizing information from documented and undocumented reports, public and private files, and personal communication with local, State, and Federal agencies. Some of the more important data sources are listed below. Data for Fall 2022 and Fall 2023 groundwater elevations and preceding water year (July 2022 to June 2023) production were obtained from the primary water purveyors in the Bunker Hill Basin including:  City of Colton  City of Loma Linda  City of Redlands  City of Riverside  City of San Bernardino SBV Water Conservation District 12 Bunker Hill Basin 2024 Engineering Investigation  Cooperative Well Measuring Program  East Valley Water District  Elsinore Valley Municipal Water District/Meeks and Daley Water Company  Fontana Water Company  Gage Canal Company  Riverside – Highland Water Company  Southern California Edison  San Bernardino Valley Municipal Water District  West Valley Water District  United States Geological Survey, Santee, CA Office Historic and current precipitation data were obtained from the San Bernardino County Department of Transportation and Flood Control and were updated this year to match their database: http://www.sbcounty.gov/dpw/pwg/Precip_Data/Zone_7_Boundry_Map.htm SBV Water Conservation District 13 Bunker Hill Basin 2024 Engineering Investigation 3.0 Fall 2022 and Fall 2023 Groundwater Elevation Contours The District, the Western Municipal Water District, and the primary water purveyors in the Bunker Hill Basin provided Fall 2022 and 2023 water level data. Static groundwater elevations for wells throughout the Bunker Hill Basin are compiled in Appendix A. These elevations for approximately 200 wells using a Geographic Information System (GIS) are plotted in Figure 5 and Figure 6 for Fall 2022 and Fall 2023. The water elevation values were used to derive an interpolated surface for the extent of the Bunker Hill Basin. For purposes of comparison, Fall 2022 and Fall 2023 static groundwater elevation surface contours are provided in Figure 5 and Figure 6 respectively. SBV Water Conservation District 14 Bunker Hill Basin 2024 Engineering Investigation 4.0 Task 1 – Annual Change in Storage (Fall 2022 to Fall 2023) 4.1 Hydrologic Sub-areas Using a Geographic Information System, the average groundwater elevation changes were determined for each of the nine hydrologic sub-areas shown in Figure 3 and listed below.  Bunker Hill I - Southwest of Interstate 215  Bunker Hill I - Northeast of Interstate 215  Bunker Hill II - West of Mentone Fault  Bunker Hill II - East of Mentone Fault  Lytle Basin - Southeast of Barrier J  Lytle Basin - Northwest of Barrier J  Pressure Zone - North of Santa Ana Wash  Pressure Zone - Santa Ana Wash Due to variations of changes in groundwater level elevation, the Bunker Hill II - East of Mentone Fault was further subdivided into Storage Units North of Redlands Fault and Southeast of Redlands Fault. These Storage Units are also shown in Figure 3. 4.2 Area and Storativity Digitizing each polygon made estimates of the area extent of the sub-areas and storage. Average storativity for each sub-area was determined based on data from Hardt and Hutchinson, 1980. Both of these values are shown in Table 3. Storativity values range from 0.02 for the Pressure Zone - North of the Santa Ana Wash to 0.13 for the Lytle Basin - Northwest of Barrier J and Bunker Hill II - East of the Mentone Fault. 4.3 Groundwater Level Elevation Changes In order to determine the annual change in storage for the Bunker Hill Basin, Fall 2023 groundwater level elevation data were compared with the same from Fall 2022. Measurements for 233 wells were available for both periods and the differences are provided in Appendix A. Figure 7 shows key wells for the Bunker Hill basins. These wells have long hydrologic histories. SBV Water Conservation District 15 Bunker Hill Basin 2024 Engineering Investigation Average changes in groundwater were determined by averaging the changes for all wells in each of the eight sub-areas and storage units as shown in Table 3. 4.4 Changes in Groundwater Storage The total annual change in storage for the Bunker Hill Basin was determined by summing the changes from each sub-area. Changes in groundwater storage for the period Fall 2022 to Fall 2023 for the Bunker Hill Basin were calculated using the following formula: As shown in Table 3, the change in groundwater storage for the Bunker Hill Basin between Fall 2022 and Fall 2023 decreased a change of 226,806 acre-ft. Qchange in storage =  Ai x Si x hi where: Qchange in storage = Annual change in storage for the Bunker Hill Basin, (acre-feet) Ai = Area of sub-area and storage unit i, (acres) Si = Storativity of sub-area and storage unit i hi = Average water level change of sub-area and storage unit i, (feet) SBV Water Conservation District 16 Bunker Hill Basin 2024 Engineering Investigation 5.0 Task 2 – Accumulated Change in Storage from Fall 1993 to Fall 2023 For purposes of this report, the accumulated change in storage as of the last day of the preceding water year (July 30, 2023) was based on the changes in water levels between Fall 1993, when the accumulated basin change in storage was considered “zero”, and the Fall of 20233. The accumulated change in storage as of June 30, 2023 was determined by subtracting the change in storage for the preceding water year (July 1, 2022 to June 30, 2023) of 226,806 determined in Section 4.4, from the accumulated change in storage as of June 30, 2022 (-651,262). The result of this calculation is an accumulated change in storage for the Bunker Hill Basin of -424,456 acre- ft. Table 4 summarizes the accumulated change in storage of the Bunker Hill Basin for the period 1989 to 2023 based on 1993 as the “zero accumulated storage year”. As would be expected, storage generally increases with above average rainfall and decreases with normal and below average rainfall. 3 In the District’s Engineering Investigation (EI) prior to 1993-94, the accumulated change in storage was based on the basin storage in 1984 as considered full. A concern arose regarding high groundwater levels in the Pressure Zone of the Bunker Hill Basin. Therefore, in response to the City of San Bernardino’s comments on accumulated change in storage, all EI’s since that time are based on 1993 basin storage levels considered as full. The BTAC makes annual recharge recommendations to optimize recharge. SBV Water Conservation District 17 Bunker Hill Basin 2024 Engineering Investigation 6.0 Task 3 – Total Groundwater Production for the Preceding Water Year (July 1, 2022 to June 30, 2023) Production data for the preceding water year (July 1, 2022 to June 30, 2023) for the Bunker Hill Basin were obtained from the primary water purveyors as listed in Section 2.4. Production data for wells owned by some smaller water agencies were included if data was available from the Western-San Bernardino Watermaster, Western Municipal Water District and semiannual billing statements issued by the District. Appendix C shows the production for each groundwater well in the Bunker Hill Basin for the period July 2022 through June 2023. As summarized on the last page of the Appendix, groundwater production from the Bunker Hill Basin for the preceding water year was approximately 139,296 acre-ft. Table 5 summarizes the Bunker Hill Basin groundwater production for each of the sub-areas defined in Section 4.1. Groundwater production within the Bunker Hill Basin during the period July 2022 through June 2023 is shown on Figure 8. The Pressure Zone has the greatest density of higher producing facilities with pockets of substantial production scattered throughout the rest of the basin. SBV Water Conservation District 18 Bunker Hill Basin 2024 Engineering Investigation 7.0 Task 4 – Estimate of the Annual Change in Storage for the Current Water Year (July 1, 2023 to June 30, 2024) To estimate annual change in storage for the current water year, a multiple regression analysis was performed for the period between 1993-2023 using three parameters:  Annual Change in Storage  Precipitation  Production This analysis is shown in Figure 9. In Engineering Investigations (EI) prior to 1998, data for the period 1982 calendar year through 1991 calendar year were also utilized in the regression analysis. The only production data available for this time frame was based on a calendar year period instead of the June to July period required in the EI. Since the 1991-92 period, more accurate and more complete production data for the July to June period has become available, as the District has compiled detailed information for its EI. Since 1998, the regression analysis has not included pre-1991 data to more accurately represent June through July production. Annual change in storage for the current water year is estimated using the following relationship between change in storage, precipitation, production, and the calculated regression coefficients. The accumulated change in storage is shown in Figure 9. QAnnual Δ storage = -134,511 + 8,308 * Qprec - 0.228 * Qprod Qprod = 202,724 + -261.18* Qprec where: Q Annual Δ storage = Annual change in storage, (acre-feet) Qprec = Annual Precipitation, inches Qprod = Annual Production, acre-feet SBV Water Conservation District 19 Bunker Hill Basin 2024 Engineering Investigation A nomograph, constructed using the above equation, is shown on Figure 9. Through the use of this chart or the equation above, annual change in storage can be estimated for a given set of annual precipitation and production values. The precipitation used in the nomograph is based on the average of the representative Bunker Hill Basin drainage area stations listed in Table 6. The historic annual precipitation information is shown in Table 1. The historic average annual precipitation for eight4 of the nine stations with recent data is shown in Table 6 approximately 21.23 inches. Historic annual precipitation values are plotted in Appendix D for these nine stations and eleven other local stations. Table 6 shows that for the period between July 1, 2022 and December 31, 2022, precipitation was 114.9 percent of normal for the nine stations. The remainder of the water year, January 1, 2023 to June 30, 2023, the rainfall averaged 186.4 percent of normal. Annually, precipitation for the 2022-2023 water year averaged 162.7 percent of normal. For purposes of this report, it was assumed that precipitation for the current water year (July 1, 2023 to June 30, 2024) would be 34.55 inches, 162.7 percent of the 21.23 inch average for the 2023 to 2024 season. The precipitation for the ensuing water year (July 1, 2024 to June 30, 2025) was estimated, as 100 percent of normal, or 21.23 inches of rainfall. Based on these assumptions, the estimated production for the current water year will be approximately 193,701 acre-ft as shown in Figure 10. Using this result in Figure 9 an estimated change in storage for the current water year (July 2023 to June 2024) of 108,401 acre-ft was determined. 4 Camp Angelus station was not included for 2022-2023 due to snow inundation. SBV Water Conservation District 20 Bunker Hill Basin 2024 Engineering Investigation 8.0 Task 5 – Estimate of the Annual Change in Storage for the Ensuing Water Year (July 1, 2024 to June 30, 2025) The annual change in storage for the ensuing water year (July 1, 2024 to June 30, 2025) was estimated using the same method as described in Section 7.0. It was assumed that precipitation for the ensuing water year would be 100 percent of normal or 21.23 inches. Based on this assumption, the estimated production for the ensuing water year will be approximately 197,179 acre-ft as shown in Figure 11. Again, using this result in the nomograph shown in Figure 9, the estimated annual change in storage for the ensuing water year (July 1, 2024 to June 30, 2025) is -3,007 acre-ft. 9.0 Task 6 – Average Annual Change in Storage for the Immediate Past 10 Water Years Table 7 shows the average annual change in storage for the immediate past ten water years (July 2013 to June 2023) using the same method as described in Section 4.0. By summing the average annual change in storage for each sub-area, a total average annual change in storage for the Bunker Hill Basin for the immediate past ten water years was determined to be -1,238 acre- feet/year. 10.0 Task 7 – Estimated Amount of Historically Agricultural Water and Other Than Agricultural Water to be Withdrawn for the Ensuing Water Year (July 1, 2024 to June 30, 2025) The estimated amount of agricultural water and other than agricultural water to be withdrawn within the District for the ensuing water year (July 1, 2024 to June 30, 2025) was based on the following equations: SBV Water Conservation District 21 Bunker Hill Basin 2024 Engineering Investigation Data on agricultural use and other uses within the District for the preceding water year (July 1, 2022 to June 30, 2023) are provided in Appendix C. For the period July 1, 2022 through June 30, 2023 approximately 3,547 acre-ft of groundwater was produced for historically agricultural applications within the District boundary. For the same period, approximately 66,477 acre-ft of groundwater was produced for all other uses within the District boundary. Using the equations presented above with the following values inserted: Qagr(24-25) = Qagr(22-23) x [(Qtotal(24-25) - Qsurf(24-25)) / (Qtotal(22-23) - Qsurf(22-23))] and Qnon-agr(24-25) = Qnon-agr(22-23) x [(Qtotal(24-25) - Qsurf(24-25)) / (Qtotal(22-23) - Qsurf(22-23))] where: Qagr(24-25) = Agricultural use within the District for the ensuing water year, acre-ft Qagr(22-23) = Agricultural use within the District for the preceding water year, acre-ft (Appendix C) Qtotal(24-25) = Production (including surface diversion) from the Bunker Hill Basin for the ensuing water year, acre-ft (Figure 14) Qtotal(22-23) = Production (including surface diversion) from the Bunker Hill Basin for the preceding water year, acre-ft (Appendix C) Qnon-agr(24-25) = All other uses within the District for the ensuing water year, acre-ft Qnon-agr(22-23) = All other uses within the District for the preceding water year, acre-ft (Appendix C) Qsurf(24-25) = Surface diversions from the Bunker Hill Basin for the ensuing water year, acre-ft (Table 8) Qsurf(22-23) = Surface diversions from the Bunker Hill Basin for the preceding water year, acre-ft Table 8) SBV Water Conservation District 22 Bunker Hill Basin 2024 Engineering Investigation By summing these two results, it is estimated that 99,122 acre-feet of groundwater will be withdrawn within the District for the ensuing water year (July 1, 2024 to June 30, 2025). Appendix C shows the Agriculture and Non-Agriculture trends for the District by sub-basin using approximately 100 wells within the District Boundary reporting type of use. The long term historic5 average for agricultural usage within the District is between 14,000 ac-ft and 15,000 ac-ft. This usage has dropped in the past few versions of the Report as development of farm land to industrial and commercial uses has expanded. The long term average for non-agricultural uses within the District is between 65,000 ac-ft and 75,000 ac-ft. 5 Prior to the December 2017 California Supreme Court Decision the Board Provided an Agricultural rate in accordance with CWC 755. See Appendix E. Qagr(22-23) = 3,547 acre-ft (Appendix C) Qtotal(24-25) = 271,114 acre-ft (Task 5 and 8) Qtotal(22-23) = 268,697 acre-ft (Appendix C) Qnon-agr(22-23) = 66,477 acre-ft (Appendix C) Qsurf(24-25) = 73,935 acre-ft (Task 8) Qsurf(22-23) =129,401 acre-ft (Table 8) The estimated production within the District for the ensuing water year for agricultural uses and other than agricultural uses is: Qtotal(24-25) = 197,179 + 73,935 = 271,114 acre-ft Qagr(24-25) = 3,547 x [(271,114 – 73,935) / (268,697 – 129,401)] = 5,021 acre-ft Qnon-agr(24-25) = 66,477 x [(271,114 – 73,935) / (268,697 – 129,401)] = 94,101 acre-ft Qagr(22-25) = 5,021 acre-ft Qnon-agr(24-25) = 94,101 acre-ft QDist(24-25) = 99,122 acre-ft SBV Water Conservation District 23 Bunker Hill Basin 2024 Engineering Investigation 11.0 Task 8 – Estimated Amount of Water for Surface Distribution for the Ensuing Water Year (July 1, 2024 to June 30, 2025) The amount of water for surface distribution for the ensuing water year (July 1, 2024 to June 30, 2025) was estimated based on the average surface diversions for the Santa Ana River, Mill Creek, and Lytle Creek for the period 1992 to 2023. As shown in Table 8, average surface diversions for the Santa Ana River, Mill Creek, Lytle Creek and smaller tributary creeks collectively called “Bunker Hill Creeks,” between 1994 and 2023 were 32,226; 15,238; 11,270 and 1,859 acre-feet, respectively. There was also an average of 13,341 acre-ft of imported water from 1991 and 2023 that was recharged into the Bunker Hill Basin. Therefore, the total estimated amount of water for surface distribution from the Bunker Hill Basin for the ensuing water year (July 1, 2023 to June 30, 2024) is found by summing the diversions as follows: Bunker Hill Surface Distribution = 32,226 + 15,238 + 11,270 + 1,859 +13,341 = 73,935 acre-ft As Lytle Creek and Bunker Hill Creeks are not within the District, the estimated amount of surface distribution from the District for the ensuing water year (July 1, 2024 to June 30, 2025) is the sum of the Santa Ana River and Mill Creek distributions and the imported water spread within the District Boundaries. District Surface Distribution = 32,226 + 15,238 + 4,663 = 52,127 acre-ft SBV Water Conservation District 24 Bunker Hill Basin 2024 Engineering Investigation 12.0 Task 9 – Estimated Amount of Water for Replenishment of the Groundwater Supplies for the Ensuing Water Year (July 1, 2024 to June 30, 2025) The amount of water necessary for replenishment of the groundwater supplies of the Bunker Hill Basin for the ensuing water year (July 1, 2024 to June 30, 2025) was estimated based on: Replenishment = Total Production - Surface Diversions - Change in Storage The estimated production and surface diversions from the Bunker Hill Basin for the ensuing water year (July 1, 2024 to June 30, 2025) were estimated at approximately 197,179 acre-feet (from Tasks 5 and 8) and 73,935 acre-feet (from Table 8), respectively. The estimated change in storage determined in Section 8.0 and shown on Figure 9 is a decrease of 3,007 acre-feet. Therefore, the amount of water necessary for replenishment of the groundwater supplies of the Bunker Hill Basin is estimated as follows: Basin Replenishment = 197,179 - 73,935 - (-3,007) = 126,251 acre-ft The amount of water necessary for replenishment of the District’s groundwater supplies for the ensuing water year (July 1, 2024 to June 30, 2025) was estimated using the same equation as shown above and substituting values for the District area. The estimated production within the District for the ensuing water year was estimated at approximately 99,122 acre-ft (from Section 10.0) and 52,127 acre-ft (from Section 11.0), respectively. The change in storage for the ensuing water year for the District was estimated as a decrease of 3,007 acre-ft. Therefore, the amount of water necessary for replenishment of the District’s groundwater supplies for the ensuing water year (July 1, 2024 to June 30, 2025) is: Replenishment = Total Production - Surface Diversions - Change in Storage District Replenishment = (99,122 + 52,127) - 52,127 - (-3,007) = 102,129 acre-ft The amount of groundwater recharge that must occur from all sources in order to bring the basin back to “full” in the ensuing water year is determined as follows: Replenishment = Basin Replenishment - Accumulated Change in Storage – Annual Change in Storage Total Replenishment = 126,251 - (-424,456) - (108,401) = 442,307 acre-ft SBV Water Conservation District 25 Bunker Hill Basin 2024 Engineering Investigation 13.0 Quality Assurance and Quality Control Quality Assurance and Quality Control (QA/QC) efforts for the Engineering Investigation Report are distributed. Virtually all information is provided by other programs and agencies that have their own QA/QC processes and this report relies on them for providing accurate data. Additionally, most of the data is used in other reports and would be flagged if in error; examples include Watermaster reports, other basin models, etc. This section will briefly discuss the QA/QC process and standards. 13.1 Process and Method The EI process produces results that are obtained by inputting the data we receive from the cooperating agencies into a series of linked spreadsheets in an MS Excel workbook. Many different calculations are then performed on the data entered. The results from these calculations are reported in the EI. Like all reports, the EI can contain error. SBVWCD makes a great effort to identify and eliminate the sources of possible errors. The EI has established standards for precision and representativeness in the development of the report since the process initiation in 1993. The report uses a set of key wells, which can change over time to represent the groundwater basins. If changes to the wells are made, they are reviewed to see they are consistent with prior years. The level of precision in the data supplied varies, because the District must rely on the data quality produced by others for their work. We do not have specific requirements for precision of well level or production data, because other programs use the data and because the report averages the levels over entire groundwater basins; the precision of the other programs is adequate for our change in storage calculations. In order for accurate conclusions to be drawn from the EI, the following must happen: 1) High quality data must be input into the Daily Flow Report (DFR) by field staff 2) DFR and data from other agencies must be accurately transferred to EI spreadsheets; 3) Correct calculations must be made using this data 13.2 Data Accuracy The EI uses a large amount of production, water level, and flow measurements in calculating the change in storage and related tasks. The data received for the study is reviewed for completeness SBV Water Conservation District 26 Bunker Hill Basin 2024 Engineering Investigation so that all wells and flows are reported. SBVWCD verifies that DFR data is accurate by cross checking with other data and verifying the data is in the historical range. The District implements several methods to maintain the accuracy of the Engineering Investigation Report. These methods are discussed in the following sections. The input data for the EI comes from many agencies, in many different formats, over a range of several months. The data is checked when entered to ensure that the correct data is being provided in the correct units. To ensure this check occurs, all data entered into the EI spreadsheets is highlighted. Once all data entry has occurred, a second staff person checks the highlighted input data to make sure it is the correct value and in the correct units. Generally, data is transferred (copied and pasted) into the EI spreadsheets rather than retyped to reduce entry errors. When data is provided in a format that cannot be transferred, hand entered data is double checked upon entry. Once all the data has been entered, it is checked again to make sure there is not any data out of historical range. Any data that is out of range is rechecked at the source, and if necessary confirmed by the providing agency. A final check of the data is done by the reporting agencies. SBVWCD sends out a draft EI to all data providers. Any error reported by the data providers is addressed and corrected before the Final EI is approved. 13.3 Calculation Accuracy To ensure the calculations used to obtain the results for the EI are correct, the District uses a copy of the prior year spreadsheets for the ensuing year. The spreadsheets are directly recreated from the copies, only the data is stripped out of the spreadsheet so that all cell references are maintained. This maintains the consistency of the calculations. As an additional check, the cell references and formulas are reconfirmed each year. In addition to rechecking of the structure of the spreadsheets, the methodology and logic is also rechecked in this process. 13.4 Comparability After all the data and calculations are checked, the final results are obtained. The District compares the results from the EI to SBVMWD’s groundwater modeling program change in storage calculation. The programs cover nearly the same area with very similar input data. However, the basin boundaries and methods of calculations are different. If District results and SBV Water Conservation District 27 Bunker Hill Basin 2024 Engineering Investigation SBVMWD’s results are significantly different, more than 10%, the District and SBVMWD both review data and calculations, identify any errors, and verify the new EI results are comparable and accurate. The 2024 EI change in storage value of 226,806 AF will be compared to SBVMWD’s model once it is finalized. 13.5 Approval Once the results are confirmed through the previous steps, the District Management reviews the report and recommends it to the SBVWCD’s Board of Director for reviews and approval. 13.6 Improvements and Changes to the Report There were no significant changes to the Engineering Investigation report or calculation method. SBV Water Conservation District 28 Bunker Hill Basin 2024 Engineering Investigation 14.0 General Findings In addition to the above findings, Section 75505 of the California Water Code requires that a finding be made as to the amount of water necessary to be replaced in the intake areas of the groundwater basins within the District to prevent the landward movement of salt water into the fresh groundwater body, or to prevent subsidence of the land within the District. Because of its location and the elevations of its water table, the Bunker Hill Basin is not subject to salt-water intrusion and the current groundwater levels will not (lowest=593 msl) result in any significant land subsidence. Section 75540 of the California Water Code requires that the District Board establish a zone or zones where a groundwater charge is to be implemented. The Code specifically states that a single zone may include the entire District and in May 1993 the Board established the entire District as one zone. This determination may be amended in the future, but lacking any evidence to the contrary, in the 2023-2024 year the entire District will remain as a single zone in regard to any groundwater charge. Section 75561 of the California Water Code further requires the Engineering Investigation to include a finding related to the amount of water the District is obligated by contract to purchase. At this time the District has no contractual obligation to purchase water for the replenishment of the groundwater supplies. 15.0 Conclusions Based on the results of the 2024 Engineering Investigation, the San Bernardino Valley Water Conservation District finds that:  Due to the imbalance between recharge and production since 1993, the Bunker Hill Basin’s storage is 424,456 acre-feet below that which is considered full for purposes of this Investigation. SBV Water Conservation District 29 Bunker Hill Basin 2024 Engineering Investigation  During the ensuing water year (July 1, 2024 to June 30, 2025), the Bunker Hill Basin can be recharged, from all sources, with 442,307 acre-feet of water. This recharge quantity is derived by algebraically adding together the accumulated deficit as of the end of the preceding water year with the estimated quantity needed to maintain the 1993 storage level considered full. The BTAC recommends a maximum basin recharge of 114,000 acre- ft.  The District should continue to take the necessary steps to work with its partners to enhance its capability to conduct recharge operations, which include construction of new, or maintenance and repair of existing, diversion facilities, canals, dikes, basins, roads, and other water recharge facilities. These improvements are required to ensure that the increasing demands on the Basin, especially during drought periods, can be met. 16.0 Financial Data The San Bernardino Valley Water Conservation District, in response to questions previously provided information about the groundwater charge in this section. The District provides a complete budget and report of operations as a companion document to this report. Any changes to the groundwater charge will not be reflected on the District’s financial reports as income until the fiscal year 2023 - 2024, as the first increment of the new charge is not due until that time. In 2018 the District approved a Groundwater Council Framework Agreement which includes a cost allocation model for the importation of additional State Project water when it is available. The Agreement includes a cost share portion for the operations and maintenance of spreading facilities, this cost offsets a groundwater council member’s portion of the groundwater charge. The groundwater charge is still in place for producers that are not members of the groundwater council. September 23, 2024 SNRC FOOD WASTE DELIVERY UPDATE Manny Moreno, Water Reclamation Manager 2 FOOD WASTE RECEIVING STATIONS Station 1 Station 2 3 FOOD WASTE RECEIVING PROCESS 4 •Fats Oils and Grease (FOG): Markets and restaurant grease traps (In N Out, Costco, Ralphs) •Hollandia Dairy: Milk waste •Parallel products: Juice waste •Frito Lay: Corn waste TYPES OF FOOD WASTE 5 GREASE TRAP •Wastewater flows from the source into the interceptor “grease trap” •Grease rises to the surface in different layers 6 FOOD WASTE TO POWER Biogas Generators FWGas Electricity Electric Distribution DigesterDigester 7 FOOD WASTE AND POWER PROJECTIONS 0 5 10 15 20 25 30 35 40 0 200000 400000 600000 800000 1000000 1200000 1400000 1600000 1800000 Foodwaste Trucks/Day CoGen KWH Cogen Production (kWh)Plant Demand (kWh)Trucks per day 8 CO-GENERATION ENGINE AND EMISSIONS MONITORING QUESTIONS?