A new economic analysis by Jay Lund (UC Davis), Josué Medellín-Azuara (UC Merced), and Alvar Escriva-Bou (UC Davis) shows the high cost of inaction on California’s perpetual water supply challenges, estimating that the state could lose enough water annually to supply up to 9 million households—with economic losses totaling between $3.4 and $14.5 billion per year, depending on the severity of the scenario.

The study, Inaction’s Economic Cost for California’s Water Supply Challenges, builds on prior research showing that California’s total water supply is on track to shrink by 12–25% by 2050, a loss of up to 9 million acre-feet per year, equivalent to one or two Lake Shastas. The new report emphasizes that without coordinated state action, these reductions could result in the fallowing of up to 3 million acres of farmland, the loss of 67,000 jobs, and lasting damage to California’s agricultural and rural communities.

The research underscores the urgency of Senate Bill 72, authored by Senator Anna Caballero, 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 aims to bring federal, state, regional, and local partners together to better plan, invest, and build toward a more secure, reliable, and sustainable water future.

See the full press release linked here.