1. Sediment Removal as a Water Management Strategy 2014 Sierra Water Workgroup Summit June 13, 2014

2. Panel Overview Introduction [Liz] – The bill and preliminary coordination effort Sedimentation basics [Minear] A planning tool to assess sediment removal [Yates] Evaluating sediment removal as one of a portfolio of strategies [Groves] SWWG project and outreach [Betancourt] Discussion

3. Upper Watersheds 25 “Rim” watersheds delineated by land use and elevation

4. Central Valley Water Management Model Pit R. Cow Ck. Battle Ck. Cottonwood Ck Shasta Trinity R. Clear Ck Oroville South Fk. Feather R. Almanor Big Chico Ck. Butte Ck. Elder/Thomes Ck East Park/Stony Gorge/Black Butte Cache Ck. New Bullards Bar North Fk. Yuba R. Bear R. Folsom Cross Canal North and Middle Fk. American R. North and Middle Fk. Feather R. Upper Pit R. McCloud R. 1 Net Delta Outflow Stanislaus R. San Luis San Joaquin R. Delta-Mendota Canal Camp Far West Mokelumne R. Calaveras R. Tuolumne R. Merced R. San Joaquin River Chowchilla/Fresno R. Madera Canal Eastside Bypass Millerto n McClure New Don Pedro New Melones New Hogan Pardee Putah Ck. Yolo Bypass South Fk. American Berryessa Clear Lake Stony Ck. Sacramento R. Trinity Sacramento R. Tehama-Colusa Canal Middle and South Fk. Yuba R. Sutter Bypass Glen-Colusa Canal Whiskeytow n Camanche Cosumnes R. California Aqueduct Tulloch Eastman/Hensley DELTA San Luis Friant-Kern Canal San Luis Canal Kings R. Pine Flats Kern R. Isab ella Tule R. Suc ces s Kaweah R. Kaw eah James Bypass/Fresno Slough Tulare Lake Coastal Aqueduct

5. California Water Balance

6. Regional Water Balances (2005) The bulk of developed water originates in Sacramento, San Joaquin, and Tulare Lake Regions

7. Sacramento, Feather, & American River Inflows 2065 - 2099 Water Supply Impacts Earlier runoff into reservoirs by end of century Annual runoff volume about the same 1 Million Acre-Feet = 326 Billion Gallons

8. Irrigation requirements increase with rising temperature under Business As Usual assumptions Sacramento & San Joaquin Valley Irrigation Increasing Agricultural Demands 1 Million Acre-Feet = 326 Billion Gallons

9. Zooming in to a regional Application Mehta et al, 2011 “Potential Impacts on Hydrology and Hydropower Production Under Climate Warming of the Sierra Nevada.” Journal of Water and Climate Change 2, no. 1 (March 2011): 29. doi:10.2166/wcc.2011.054.

10. Example Output: New Bullards Bar Storage, Upstream Flows

11. Example Output: Applied Irrigation Water

12. Example Output: Annual Hydropower

13. THANK YOU

14. Evaluating Sediment Removal as Part of A Water Management Portfolio Recap Central Valley vulnerability and response option analysis for California Water Plan Update 2013 Approach for incorporating sediment removal as a strategy

15. Slide 15 California Water Plan analysis looks into the uncertain future… How vulnerable is California’s water management system? How can the water management community reduce these vulnerabilities? Builds on the scenario analysis begun for California Water Plan 2005 Update Focuses on Central Valley Evaluates plausible futures out to 2050 Uses new data and tools

16. Slide 16 Nine land use scenarios reflect uncertain population growth and land use patters Three population projections for the Central Valley – Low population: 11 million habitants – Current trends: 13 million habitants – High population: 16 million habitants Three urban density scenarios – Low: More single family homes, less irrigated agricultural land – Current – High: More multi family homes, more irrigated agricultural land

17. Slide 17 Twenty-two climate scenarios reflect uncertainty about hydrologic conditions Downscaled GCM projections Historical with extended drought Historical with extended drought and warming

18. Slide 18 Performance of water management system evaluated using four key metrics Urban reliability Agricultural reliability Groundwater levels Environmental flows

19. Slide 19 Which management strategies can reduce these vulnerabilities? Urban water use efficiency Agricultural water use efficiency Recycled municipal water Conjunctive management New environmental flow targets Groundwater recovery targets New surface storage Sediment removal

20. Slide 20 How would sediment removal stack up? Sierra-wide assessment – How much sediment would need to be removed to affect state-wide water objectives under climate change? – What costs would be acceptable? Watershed assessment – Develop refined WEAP model of specific watershed and operations – Evaluate broader range of uncertainties and objectives 20

21. Slide 21 SWWG Project - Overview Based on SWWG structure – IRWM- focus IRWM-based outreach – Regional groups (SNA, SNC, SBA, MCWRA, etc.) – RWMGs – Interest-groups – Individuals

22. Slide 22 SWWG Project – Phased Approach Phase I – Outreach – Data gathering with dam owners/managers – Screening-level analysis – Assessment of impact on regional and statewide water resources management – Identification of target detail area, based on: Interest of stakeholders Results of assessment

23. Slide 23 SWWG Project – Phased Approach Phase II – Focus on specific watershed/storage system Based on stakeholder interest and outcome of assessment – Discuss and assess specific benefits: On a regional and statewide basis Response to climate change and other future uncertainty General feasibility assessment: cost/benefit

24. Slide 24 Discussion Questions 1.What critical uncertainties would affect sediment removal as a strategy? 2.What metrics should be used to evaluate sediment removal? 3.What more do we need to know?