1. Groundwater Basin Assessment Study Southern California Water Dialogue January 24, 2007

2. Water Resource ManagementJanuary 24, 2007 Approved Projects 1. N. Las Posas (Phases 1&2) 2. Long Beach 3. Foothill MWD 4. TVMWD / La Verne 5. Chino Basin 6. Orange County Basin 7. Compton 8. Long Beach - Lakewood 9. Upper Claremont Heights – TVMWD 10. Western MWD /Elsinore Valley In-Basin Groundwater Storage Projects Identified Projects 12. Raymond Basin - Foothill MWD & Pasadena 1 3 7 2 4 5 6 12 8 9 Pending Projects 11. Central Basin MWD 11 10

3. Water Resource ManagementJanuary 24, 2007 In-Region Groundwater Storage Resources IdentifiedExisting IRP Target 0 50 100 150 200 250 300 350 20052006201020202025 Thousands AF

4. Water Resource ManagementJanuary 24, 2007 Scope of Assessment Study Use of existing data and reports Use of existing data and reports Service area overview Service area overview Detailed review of 23 sub-areas Detailed review of 23 sub-areas

5. Water Resource ManagementJanuary 24, 2007 Scope of Assessment Study Basin hydrogeology Basin hydrogeology Governance Governance Facilities and operations Facilities and operations Water levels Water levels Water quality Water quality Storage programs Storage programs

6. Water Resource ManagementJanuary 24, 2007 Groundwater Basins

7. Water Resource ManagementJanuary 24, 2007

8. Raymond Basin Pasadena Monkhill Santa Anita

9. Water Resource ManagementJanuary 24, 2007 MSGB Production

10. Water Resource ManagementJanuary 24, 2007 MSGB Key Well Water Level

11. Water Resource ManagementJanuary 24, 2007 ULARA Precipitation

12. Water Resource ManagementJanuary 24, 2007 Central Basin Direct Recharge

13. Water Resource ManagementJanuary 24, 2007 Table 1 Summary of Hydrogeologic Parameters of Chino and Cucamonga Basins Chino Basin Cucamonga Basin Source: Wildermuth, 2005 and DWR, 2004 Chino Basin Aquifer Capability Parameter Structure Upper aquifer: Unconfined Deep aquifer: Confined UnconfinedAquifer(s) Yield and Storage 140,000 AFY 13,800 AFY to 22,200 AFY 145,000 AFY 22,721 AFY ~ 6 million AF Unknown ~1 million AF Unknown ~500,000 AF Unknown Natural Safe Yield Adjudication Amount Total Storage Unused Storage Space Avail. Storage Space

14. Water Resource ManagementJanuary 24, 2007 Central Basin Governance AgencyRole California Department of Water Resources Court appointed Watermaster to manage water quantity Water Replenishment District of Southern California Groundwater replenishment in Central and West Coast Basins Los Angeles County Department of Public Works Operation of spreading facilities and Alamitos Barrier facilities Sanitation Districts of Los Angeles County Produces recycled water for Montebello Forebay Spreading Grounds Los Angeles Regional Water Quality Control Board Issuance of permit for spreading of recycled water in Montebello Forebay

15. Water Resource ManagementJanuary 24, 2007 Chino Spreading Capability (Partial List) Basin Wetted Area (acres) Recharge Capacity (cfs) Recharge Capacity (AFY) Brooks Street 7.753,000 Montclair28.2107,770 7 th & 8 th Street 14.551,350 Upland10.142,730 Ely35.732,880 Source WaterOwner Runoff Imported CBWCD Runoff Imported CBWCD Runoff SBCFCD Runoff Imported City of Upland Runoff Recycled SBCFCD/ CBWCD

16. Water Resource ManagementJanuary 24, 2007 Table 5 Summary of Constituents of Concern in Main San Gabriel Basin ConstituentRangeDescription TDS (mg/L) 90 to 4,288 Average ~ 367 Municipal wells indicate a range of 172 to 914 mg/L (average of 318 mg/L) Nitrate [as N] (mg/L) ND to 27.8 Exceed nitrate MCL in eastern portion of basin. VOCs [TCE and PCE] (μg/L) TCE: ND to 499 PCE: ND to 330 64 wells are currently treated for VOCs Perchlorate (μg/L) ND to 183 22 wells removed from service due to perchlorate levels (treatment facilities are currently online) NDMA (ppt) ND to > 2 8 local wells have NDMA above action level of 2 ppt (3 facilities currently in operation) Source: Watermaster, 2004 and DWR, 2003 MSGB Water Quality Issues

17. Water Resource ManagementJanuary 24, 2007 MSGB Treatment Operations MSGB Treatment Operations Treatment Type # of Wells Contaminant Treatment Target Treatment Cost ($/AF) Amount Treated (AFY) Air Stripping 39VOCsND$2547,000 LPGAC16VOCsNDVaries14,000 Ultra- Violet / Oxidation 91,4-DioxaneND$1006,000 Ion Exchange17PerchlorateND$2006,000 Ultra-Violet 12NDMAND$1006,000 Total93 -- ND -- 79,000

18. Water Resource ManagementJanuary 24, 2007 SummarySummary Baseline report that expands upon DWR Bulletin 118 and the AGWA report Overview of basin management and use Report complete later this year

19. Water Resource ManagementJanuary 24, 2007