Sacramento-San Joaquin Delta Watershed Drought Information
The Sacramento-San Joaquin Delta (Delta) watershed is a crucial source of water for much of California and has immense ecological and cultural importance. The Delta watershed comprises approximately 40 percent of California’s land mass and constitutes the state’s largest source of surface water. The Delta is home to numerous fish, wildlife, and plant species listed as threatened, endangered, or special status under the state and federal Endangered Species Acts. The Delta watershed also supports a number of fish species, such as salmon and steelhead, that hold economic and cultural significance to California tribes, local communities, and fishing industries.
Unusually warm temperatures and dry soils have resulted in unprecedented reductions in runoff from the Sierra-Cascade snowpack, resulting in significantly less inflow to the state’s major reservoirs. Reduced runoff has caused an unexpected loss of nearly 800,000 acre-feet of water, enough to supply more than 1 million households for a year and nearly the entire capacity of Folsom Reservoir.
California is experiencing a second consecutive year of dry conditions, which has resulted in drought or near-drought conditions throughout the state. On May 10, 2021, Governor Newsom declared a drought emergency for 41 counties, including those within the Delta watershed, where accelerated action is needed to protect public health, safety, as well as the environment.
How to Conserve
Delta watershed residents can help! Surface and groundwater users can help lessen drought impacts, and even small efforts can result in huge benefits for flows and fish.
Here are just a few ways to help:
- Reduce diversions from surface and groundwater sources
- Conserve water, limit non-food irrigation, and reuse graywater (i.e., water from sinks, showers, baths, washing machines, or dishwashers)
- Coordinate diversion timing with neighbors to reduce cumulative effects
- Prepare for ongoing drought by exploring water storage options (e.g., rain collection, roofwater harvesting, or tank storage)
Photo credit: CA Dept of Water Resources.
How to Report an Unauthorized Diversion or Water Waste
Delta Watershed Water Unavailability
- Press Release: Drought conditions prompt restrictions for some Delta water right holders (June 15, 2021)
- Board Meeting Informational Item: Update on Water Unavailability Methodology for the Delta Watershed (June 1, 2021)
- Workshop on Water Unavailability Methodology for the Delta Watershed (May 21, 2021)
- Governor Newsom’s Emergency Drought Proclamation (May 10, 2021)
A notice of water unavailability is used to inform diverters that, based on the best available information, there is insufficient water available to divert under their priority of right. The State Water Board uses its Water Unavailability Methodology for the Delta Watershed to identify which water rights in the Delta watershed face insufficient supplies for diversion.
If you received a notice of water unavailability for your post-1914 appropriative water right, please use the online Water Unavailability Certification Form (form) to respond to the State Water Board. If you have a pre-1914 appropriative or riparian claim, you do not need to complete the form right now, but you may be asked to do so soon. The login information you need to access the online form is provided on the upper-right of your notice of water unavailability.
If your water right application is pending and you do not have login information to access the online form, please download a copy of the form here. Information on where to submit the downloaded form is provided at the top of the form. You should only use the downloadable form if you do not have the login information needed to access the online form.
The State Water Board may consider adopting emergency curtailment regulations pursuant to the directives in the Governor’s emergency drought proclamation. Emergency regulations may allow for curtailment orders that direct water right holders to stop diverting, including under pre-1914 appropriative or riparian claims.
Check back here for future updates on the development of possible emergency regulations for the Delta watershed.
Photo credit: CA Dept of Water Resources.