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1 Envisioning Futures for the Sacramento-San Joaquin Delta Ellen Hanak Public Policy Institute of California Jay Lund University of California, Davis
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2 Economists: Ellen Hanak, PPIC Richard Howitt, UC Davis Engineers: Jay Lund, UC Davis William Fleenor, UC Davis Geologist: Jeffrey Mount, UC Davis Biologist: Peter Moyle, UC Davis Authored by Interdisciplinary Team
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3 Major Themes Current Delta is unsustainable for almost all stakeholders Improved understanding of the Delta provides opportunities for new solutions Promising alternatives exist Most Delta users have ability to adapt Promising solutions are unlikely to arise from a stakeholder-only process
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4Outline Why the Delta matters California’s Delta crisis New thinking about the ecosystem Some long-term alternatives Screening of alternatives Recommendations
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5 The Sacramento-San Joaquin Delta Above sea level Sea level to -10 feet -10 feet to -15 feet -15 feet and below Export pumps
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6 Why the Delta Matters to Californians Water Supply Recreation Ecosystem Housing Agriculture Infrastructure
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7Outline Why the Delta matters California’s Delta crisis New thinking about the ecosystem Some long-term alternatives Screening of alternatives Conclusions and recommendations
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8 A Three-pronged Crisis Levees at increasing risk –Sea level rise and sinking land –Floods and earthquakes Steep declines in many fish species –Many are “listed” –Culprits: invasive species, habitat loss, pumps Governing institutions lacking –Resurgence of legal actions
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9 Emerging Policy Responses New studies on fish declines and levee risks Emergency funds for levee repairs “Delta Vision” process Bay-Delta Conservation Plan Stakeholders promoting several approaches –Shoring up levees, peripheral canal, reduced water exports
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10Outline Why the Delta matters California’s Delta crisis New thinking about the ecosystem Some long-term alternatives Screening of alternatives Recommendations
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11 Since 1920s, California Policy Has Aimed to Keep the Delta Fresh 1945 USBR report Delta farmers and water exporters benefit from low salinity,,
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12 In 1940s, Central Valley Project Created “Hydraulic Barrier” for Water Exports Arrows show movement of fresh water from storage
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13 Hydraulic Barrier Prevents Seasonal and Dry-year Salinity Incursions 1870s drought Summers, 1908-1917 Hydraulic barrier (since 1940s) Dotted lines show extent of saltwater incursions
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14 But Static, Freshwater Delta Not Good for Native Species Native species evolved in a fluctuating Delta Alien species have taken hold and harm native species Alien species do best with constant salinity (fresh or saline) Restoring fluctuating conditions may be key to native species’ survival Overbite clam Brazilian waterweed Asiatic clam
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15Outline Why the Delta matters California’s Delta crisis New thinking about the ecosystem Some long-term alternatives Screening of alternatives Recommendations
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16 Nine Delta Alternatives Freshwater Delta –Two levee-based alternatives –Physical salinity barrier Fluctuating Delta –Two peripheral canal alternatives –Armored-island aqueduct Reduced-exports Delta (*also fluctuating) –Opportunistic Delta* –Eco-Delta* –Abandoned Delta
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17 5) South Delta Restoration Aqueduct: A New Peripheral Canal Idea Improves South Delta and lower San Joaquin River water quality Lower San Joaquin flood bypass for flood control and ecosystem benefits Main rivers Delta waterways Brackish tidal area Freshwater tidal area Canal Optional canal Release facility
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18 6) Armored-Island Aqueduct: A Through-Delta Solution Keeps eastern Delta fresh Allows western and central Delta to fluctuate Channel to river Dredged channel Fortified levee Potential flooded islands
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19 8) Eco-Delta: An Example of Local Specialization Allows opportunistic pumping, but at lower levels Main rivers Delta waterways Flooded islands/bypass Brackish tidal area Freshwater tidal area Upland game/waterfowl Experimental Wetlands Possible storage
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20Outline Why the Delta matters California’s Delta crisis New thinking about the ecosystem Some long-term alternatives Screening of alternatives Recommendations
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21 Screening Criteria Ecosystem performance Water exports Economic and financial costs –Focus: water supply and salinity –Tools: models and existing studies Other Delta services (qualitative)
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22 Fluctuating Delta Alternatives Are Most Promising AlternativesEnvironmental Performance Annual Water Exports Economic and Financial Costs 1. Levees as UsualPoor0 – 6+ maf~$2 Billion + failures 2. Fortress DeltaPoor 6+ maf > $4 Billion + lost islands 3. Saltwater BarrierPoor$2 – 3 Billion + lost islands 4. Peripheral Canal PlusPromising - allows Delta to fluctuate $2 – 3 Billion + < $70 M/year 5. South Delta Aqueduct$2 – 3 Billion + < $41 M/year 6. Armored-Island Aqueduct Mixed$1 – 2 Billion + < $30 M/year 7. Opportunistic DeltaPromising2 – 8 maf$0.7 – 2.2 Billion + < $170 M/year 8. Eco-DeltaBest?1 – 5 mafSeveral $ Billion + < $600 M/year 9. Abandoned DeltaPoor0$500 Million + ~$1.2 Billion/year
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23Outline Why the Delta matters California’s Delta crisis New thinking about the ecosystem Some long-term alternatives Screening of alternatives Recommendations
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24 Steps Needed for a Long-term Solution Focus on promising alternatives Create technical track to explore solutions with problem-solving R&D Enhance regional and statewide representation in Delta land use decisions (e.g. SF BCDC) Implement “beneficiaries pay” financing Establish mitigation mechanisms – everyone will not “get better together”
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25 “No Regrets” Short-term Actions Emergency preparedness “Do not resuscitate” list for some islands Delta land use –Flood control guidelines for urbanization –Habitat protection Restoration projects for pelagic fish habitat
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26Questions? For the full report, research brief, and other materials, go to: www.ppic.org www.ppic.org
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