Sustainable Wastewater Reclamation and Reuse

1. Sustainable Wastewater Reclamation and Reuse Takashi Asano SlawomirW. Hermanowicz Department of Civil and Environmental Engineering University of California, Davis and Berkeley

2. Photo Credits • California Department of Water Resources • Water Education Foundation • Du Pont Permasep Products

3. Presentation Outline • State of California as an Example • Population growth and urbanization • Sustainability and Water • The role of water reuse with examples • Technological Development • How safe is water reuse

5. Increasing Water Demand in California (Water Plan Update 160-98) 1995 2020 Urban 11% Environmental 46% Environmental 46% Agricultural 43%

6. Sustainability and Water • Meet supply and demand

7. Sustainability and Water • “We are here consecrating this water supply and dedicating the Aqueduct to you and your children and your children’s children for all time.”

11. 1995, by Ray Sterner, Johns Hopkins University

12. 200 commercial crops, ¼ of the nation’s table foods, and ½ of fruits and vegetables

21. Recovering Sustainable Water from Wastewater

22. The Role of Water Reuse - 1 • Very often society no longer has the luxury of using water only once • For water supplies to be sustainable, the rate at which water is withdrawn needs to be in balance with the rate of renewal or replenishment • Water recycling and reuse as an alternative water resource • Drought and dependable water supply

23. The Role of Water Reuse - 2 • Seven categories of water reuse - examples • Treatment technologies and process reliability • How safe is water reuse? • Future perspectives - all living species in harmony

25. Repurified water/ NEWater Water Reclamation and Reuse Drinking Water Quality of Water Unpolluted Water Reclaimed Water Municipal and Industrial Use Water Treatment Wastewater Treatment Treated Effluent Wastewater Time Sequence (No Scale) Quality Change in Use of Water

26. Categories of Reuse 1. Agricultural Irrigation 2. Landscape Irrigation 3. Industrial Reuse 4. Groundwater Recharge 5. Recreational and Environmental 6. Nonpotable Urban Reuses 7. Potable Reuse

27. Reclaimed Water Use in California Source: May 2000, Office of Water Recycling, California State Water Resources Control Board

28. Wastewater Reuse

29. 2000 Other Imported 11% Ground Water 3% MWD 84% Transfers 25% Ground Water 7% Surface Water 11% Surface Water 11% Recycling 7% Recycling 2% Seawater Desalination 3% MWD 36% Regional Water Supply Sources Comparison – San Diego, CA 2020

36. Orange County Water Factory 21 Granular Activated Carbon Chlorine Disinfection Deep Well Injection Lime Clarification Recarbon-ation Filtration Reverse Osmosis Aquifer Recharge 1976 - 2004 (28 years of operation) 21 million M3/ yr (15 mgd) No more than 5% of the reclaimed water actually comprises the domestic supply No observed water quality degradation that constitutes a public health concern

48. Benefit of Water Reuse • Important element of integrated water resources management • Treated effluent is used as a water resource for beneficial purposes • The wastewater is kept out of streams, lakes, and beaches; thus reducing pollution of surface water and groundwater

49. How safe is water reuse?  Acceptable health risks debate • Absolute risk vs. relative risk  Microbiological risk assessment • Enteric virus control by treatment technologies • Regulatory oversight  Chemical risk assessment