Over the last few decades, the California climate has warmed, with the effects felt strongly in water resources. The state has already experienced a marked increase in the variability of precipitation, with wild swings from drought to flood. 

Without action, the ability of the State Water Project to reliably deliver water to homes, farms and businesses will decline.  The report published today, the first-ever State Water Project Adaptation Strategy assesses and details over a dozen different state actions to protect the state’s water supply through the State Water Project. 

The report focuses on five actions to help the state successfully climate-proof California’s water supply through the State Water Project.  California is expected to lose 10% of its water supply due to hotter and drier conditions by 2040, threatening the water supply for millions of Californians — and the reliability of the State Water Project could be reduced by as much as 23%.  

The Delta Conveyance Project will help offset and recover these future climate-driven water losses, and yet, it has been plagued by delays and red tape. 

The Delta Conveyance Project would expand the state’s ability to improve water supply reliability, while also maintaining fishery and water quality protections. During atmospheric rivers last year, the Delta Conveyance Project could have captured enough water for 9.8 million people’s yearly usage.

 The most promising action to improve water supply reliability is the construction of the Delta Conveyance Project for the following reasons:

• The project is the single most effective strategy on its own, but it also amplifies the impact of other strategies.
• The project would safeguard water deliveries from disruption in the event of levee collapse in the Delta and would enable the SWP to capture more storm runoff.
• Additionally, the project would help prevent water delivery disruptions by providing protection against earthquakes and other climate-related disasters.

“Anything that compromises the State Water Project poses a threat to public health and economic success,” said DWR Director Karla Nemeth. “This analysis helps us understand the best science-based strategies to ensure continued State Water Project deliveries in the face of both greater aridity and more powerful storms. We need that not just for the public water agencies that pay for the State Water Project, but to continue the role the State Water Project plays in protecting Delta water quality during drought and upstream communities during floods.”