California weather is becoming characterized by more extreme variability with climate change. The state’s water security is at risk. In the last ten years, the state has experienced two droughts followed by near-record rainfall. Water managers are struggling to fix dams to handle floods and prepare irrigation systems for the next drought.

A new report by Pacific Forest Trust looks further upstream to find a long-term and highly cost-effective water security solution: repairing and maintaining California’s watersheds.

A Risk Assessment of California’s Key Source Watershed Infrastructure is the first comprehensive assessment of the seven million acres across five watersheds that feed the Shasta and Oroville reservoirs, the core of the state’s utilized water supply—and it outlines a framework to restore and maintain resilient watersheds.

Read the report below or download the report as a PDF here.

A Risk Assessment of California’s Key Source Watershed Infrastructure shows that half of the source watersheds that supply northern California’s primary reservoirs are at risk due to impacts from climate change, management patterns and development. Findings indicate watershed function, already severely degraded, cannot be relied upon to sustain California’s water security needs without significant repair and maintenance.

This report evaluates conditions, repair, and maintenance needs for the Feather, Pit, McCloud, Upper Sacramento, and Upper Trinity River watersheds. These five sources feed the Oroville and Shasta reservoirs, which provide drinking water for over 28 million Californians and supply the large majority of the water for the State Water Project.

Last year, Governor Jerry Brown signed legislation recognizing watersheds as a critical component of California’s water infrastructure, just like the state’s dams, canals and levees. AB 2480 established that the maintenance and repair of source watersheds is eligible for the same forms of financing as other water collection and treatment infrastructure, calling out these source watersheds for their specific importance.