1. LESJWA Water Summit October 5, 2011 Ronald E. Young, P.E. DEE General Manager

2. 2008 1964

3. 1. Rain 2. Local Groundwater 3. Recycled Water 4. Imported Water

4.  (+) Low Cost Pretty Clean  (-) Unpredictable Floods: 1841, 1862, 1864, 1884, 1916, 1937-38, 1941, 1969, 1978-80, 1983, 1993 Dry: 1810, 1859, 1951, 1958, 1964 Contain Nutrients from Urban Areas and Agriculture

5.  (+) Island Wells Built by State 1966-68 Wells Not Potable Quality (Sulfur & Temperature)  (-) Power Cost and Maintenance - $225/AF Indirect Impact on Basin Groundwater Levels

6.  (+) Readily Available from Local Area High Quality, Meets State Biological Standards Accepted by Public  (-) Contains Nutrients Cost of Treatment - $217 /AF Strict Nitrogen and Phosphorus Limits

7.  (+) Provided by MWDSC – Colorado River or State Water Project Delivered Through Canyon Lake 1964 – 1966 Purchased 44,250 AF (or 15 feet water)  (-) Not Always Available Expensive $494 /AF

8. Rain - Average: 10,000 AF/year Local Groundwater - Average: 1,000 AF/year Recycled Water - 5,500 AF/year Imported Water - ? Evaporation - 15,000 AF/year

9. TDS (salts)-Requirement-2,000 mg/l Lake Objective Actual RW about 700 mg/l Total Nitrogen Requirement-1.0 mg/l & <16,372 #/yr Actual 3 mg/l – excess offset by aeration Total Phosphorus Requirement-0.5 mg/l & <8,186 #/yr Actual 0.3 mg/l & 5,300 #/yr

10. 1997- Recycled Water Task Force - White Paper – 18 Citizens Agree 2001- Lawsuit for Water To Lake 2003- Settled Lawsuit with R-W & Island Well Water To DateIsland Wells9,136 AF Recycled Water 26,915 AF Total 35,750 AF

11. 2002- $1.4M Island Wells Improved 2003- 1.4M Axial Flow Pumps 2004-.5M Island Wells Piped to Wetlands 2007- 2.2M Aeration System 2008- 1.8M Permanent Pipe 2009-.8M Phosphorus Removal

12. Dilutes Salts and Nutrients Improves Environment for Biomanipulation Reduces Chlorophyll-a (Algae)