Main San Gabriel Basin Management BASIN REPLENISHMENT by Anthony C. Zampiello

1. Main San Gabriel Basin ManagementBASIN REPLENISHMENTby Anthony C. Zampiello San Gabriel Valley Water Forum Presented August 28, 2012 SAN GABRIEL VALLEY MUNICIPAL WATER DISTRICT THREE VALLEYS MUNICIPAL WATER DISTRICT SAN GABRIEL VALLEY MUNICIPAL WATER DISTRICT

2. Main San Gabriel Basin Watermaster • Water rights dispute in San Gabriel Valley led to adjudication in 1972 • 9-person Watermaster Board created to administer judgment • Actions under continuing Court jurisdiction

3. MSGB Watermaster Board • 6 Producer Representatives -- nominated annually from Water Rights Holders • 3 Public Agency Representatives -- appointed annually from Municipal Water District Boards

4. Main San Gabriel Basin Watermaster • Monitors and Manages Groundwater Extractions • Monitors and Manages Day to Day Water Quality of the Basin • Annually Determines the Operating Safe Yield for the Basin • Orders Replacement Water Purchases

5. New Management Tool • June 21, 2012, Judgment Amendments Approved • Extensive Outreach to All Parties • No Opposition • Over Twenty Amendments Were Included • Increased Adaptability To Supply Conditions • Included Administrative and Operational Fixes

6. Key Judgment Amendments • Export and Storage of Supplemental Water • Public Policy Education • Replacement Purchase Flexibility • Spread of Import Water Above 250 feet (AMSL) • Water Resource Development Assessment • Supplemental Assessments • Replacement Water-Purchase Planning in Conjunction with Responsible Agencies

7. Main San Gabriel Basin Physical Setting • Underlies San Gabriel Valley • Approximately 167 square miles of surface area • Serves 80 Percent of Valley Water Needs • Approximately 1.4 million people • Annual Water Production: • Approximately 230,000 - 260,000 acre-feet

10. Getting Water to the Consumer

11. SAN GABRIEL VALLEY MUNICIPAL WATER DISTRICT THREE VALLEYS MUNICIPAL WATER DISTRICT SAN GABRIEL VALLEY MUNICIPAL WATER DISTRICT

12. Why is Groundwater So Important to the Valley? • Original Basin Management Structure • Emphasis Placed On Groundwater Supply Related Facilities (Wells, Reservoirs, Booster Plants) • Reliance Upon Groundwater Replenishment Deliveries • Interruptible Supply/Replenishment Rate (~$100/AF Interruptible Rate Reduction) • 30,000 To 50,000 AFY

13. Main Basin Physical Solution • Main Basin Judgment – 1972 (40 Years Of Basin Management) • Physical Solution • “Conjunctive Use” Of Surface Water, Groundwater, Supplemental Water, And Groundwater Storage – Not A New Concept • Annual Operating Safe Yield Established Based On Current Hydrologic Conditions – Extractions Without Replacement Water Fee • Allows/Anticipates Over Production To Meet Demands – Replacement Water • Depends On Reliable Untreated Supplemental Water To Replace Over Production • Responsible Agencies Deliver Supplemental Water As Replacement Water • MWD Member Agencies (SWP/Colorado River) • Upper District • Three Valleys District • San Gabriel District (SWP 28,800 AFY)

14. Managing Replacement Deliveries • MWD Untreated Imported Water Deliveries • Replenishment Water Rate • “Good Ol’ Days” Historically Available 1972-2007; Replenishment Water On Interruptible Basis • MWD Cyclic Storage Account (140,000 AF To 100,000 AF Capacity) • Allowed MWD To Deliver/Store Significant Volume Of Surplus Water ; Interruptible, Cyclic Storage ± 50,000 AF • Replenishment Rate (Most Recently $442/AF V. $560/AF For Tier 1, Untreated, Full-Service Water) • Historically Never Subject To Readiness To Serve (RTS) Charge (Only FIRM Deliveries Not Interruptible Deliveries) • Replenishment Rate Suspended In May 2007

15. Establishing The Operating Safe Yield • Each Year Board Considers Several Factors: • Current and projected groundwater elevation at the Key Well. • Historical and current hydrologic conditions within the Basin • Rainfall • Storage of local runoff in surface reservoirs • Conservation of local runoff • Availability of supplemental imported water • Quantity of water in Cyclic Storage • Carry-over rights • Other

16. Main San Gabriel Basin Management • Basin Replenish Reliability Opportunities • Under Physical Solution • Continue To Work With MWD For Firm/Reliable Untreated Water Supply (Annual Contract?) • Develop A Supplemental Recycled Water Program • Promote Conservation • Fully Develop Capacity to Capture Large Storm Events • Limited Options Without Physical Solution • Limit Production To Basin Natural Safe Yield • Construct New Treated Water Connections To MWD And Develop Increased Allocation

17. Local Supply Challenges • Imported Supply Reliability • Sediment Management • Critical Habitat Designations • Flood Management • Meeting Future Demands

18. The Simple Truth • So California Coastal Plain is a dry region • Some areas rely heavily on imported water • SGV groundwater can sustain us through several years of drought • Improvements needed to enhance water supply reliability • Maximize groundwater storage opportunities • Additional infrastructure to maintain groundwater levels, increase operational flexibility

19. Questions