C A L I F O R N I A D E P A R T M E N T O F W A T E R R E S O U R C E S

California Aqueduct Subsidence

February 10, 2020

• Supplies water to 27 million people and 750,000 acres of farmland

• Up to 3 feet of subsidence during recent drought

• Subsidence projected to continue if no action is taken

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California Aqueduct

Extent of Subsidence

Recent DWR Studies

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•Subsidence due to deep groundwater pumping

•Over 2 feet of subsidence from recent drought can not be recovered

•Transition from annual to perennial crops

•Aqueduct capacity reduced by 20% in some locations

•Reduced Aqueduct operational flexibility

Impacts on the Aqueduct

• Decreased delivery capacity

• Increased cost to deliver water

• Decreased system reliability

• Increased operations and maintenance

Impacts – Damaged Liner

Impacts – Subsided Gate

• Restore delivery capacity for reliable water delivery

• Restore operational flexibility

• Long-term infrastructure resiliency

• Affordability

• Pursue supplemental funding

Key Considerations

Sustainable Groundwater Management Act

• Engage with sustainable groundwater agencies and others

• Protect the Aqueduct from further damage

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What’s Next?Near-term Efforts

• Raise portions of the Aqueduct

• Repair siphons and gate structures

• Raise bridges over Aqueduct

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Long-term Efforts

• Conduct feasibility study

• Plan, design, and implement enduring repairs to the Aqueduct

Questions?