California is on track to lose between 12–25% of its total water supply by 2050

by AGC News
Jun 5
2 min read

A new statewide economic analysis is shedding light on what could be the most costly agricultural challenge facing California in the coming decades: inaction on long-term water supply.

The study, Inaction’s Economic Cost for California’s Water Supply Challenges, conducted by Dr. Jay Lund (UC Davis), Dr. Josué Medellín-Azuara (UC Merced), and Dr. Alvar Escriva-Bou (UC Davis), warns that without coordinated efforts, California is on track to lose between 12–25% of its total water supply by 2050. That equates to up to 9 million acre-feet per year—roughly one or two Lake Shasta's worth of water—and enough to serve 9 million households annually.

The report outlines a grim future if state leadership fails to act: up to 3 million acres of farmland fallowed, 67,000 jobs lost, and between $3.4 and $14.5 billion in annual economic losses across the state.

“We’ve done the math—and the costs of inaction are high economically and environmentally,” said Dr. Jay Lund, Professor of Civil and Environmental Engineering at UC Davis. “California urgently needs a long-term, statewide strategy to prepare for growing water challenges ahead.”

SB 72: California’s Roadmap to a More Reliable Water Future

In response to these alarming projections, Senator Anna Caballero has introduced Senate Bill 72, which would create the first-ever statewide water supply target and direct California to develop 9 million acre-feet of new water supply by 2040. The bill calls for a unified, coordinated investment in tools like stormwater capture, water recycling, desalination, and upgraded infrastructure.

“California’s water system was designed for a climate that no longer exists,” said Senator Caballero. “SB 72 provides a roadmap to adapt our water strategies and tactics to meet the demands of our changing environment, expanding economy, and growing population.”

“From the local perspective, a statewide strategy to improve California’s water resilience that includes long-term planning and investment will not succeed without measurable outcomes and timelines,” added Paul Cook, General Manager of Irvine Ranch Water District. “SB 72 represents a critical step toward aligning regional efforts with a broader, coordinated vision—ensuring that communities across California are better equipped to address ongoing and future water supply challenges.”

The study identifies four key drivers behind California’s projected water losses:

Implementation of SGMA and limits on groundwater extraction
Reduced snowpack due to climate change
Greater environmental water needs, including ecosystem protections and sea-level rise
Declining Colorado River allocations, particularly affecting Southern California

What It Means for Agriculture

The agricultural industry stands to lose the most from prolonged inaction. Water scarcity, subsidence, regulatory burdens, and shifting climate conditions already challenge growers across the Central Valley and beyond.

SB 72 offers a strategic path forward—one that could protect farmland, bolster food production, and help safeguard rural jobs.

“SB 72 provides a roadmap to adapt our water strategies,” said Senator Caballero. “We need to plan and build toward a more secure, reliable, and sustainable water future.”