From the State Water Resources Control Board:
This email contains important information about the curtailment status of water rights and claims of right within the Sacramento-San Joaquin Delta (Delta) watershed pursuant to Initial Orders Imposing Water Right Curtailment and Reporting Requirements in the Delta Watershed (Order for water rights/claims under 5,000 acre-feet and Order for water rights/claims over 5,000 acre-feet).
Current weather forecasts call for additional precipitation and runoff in the Delta watershed in the near future. Today’s curtailment status update suspends some existing curtailments based on the updated output of the Water Unavailability Methodology for the calendar month of December. The following water rights are curtailed, effective December 2, 2022, unless and until the State Water Board advises that this determination has been updated:
1. Water rights and claims on the following Sacramento River tributaries:
- Post-1914 appropriative water rights and pre-1914 appropriative water right claims in the Cache Creek subwatershed with a priority date of 1856 or later;
- Post-1914 appropriative water rights in the Stony Creek subwatershed with a priority date of 1930 or later;
- Post-1914 appropriative water rights in the Bear River subwatershed with a priority date of 1942 or later; and
- Post-1914 appropriative water rights in the Putah Creek subwatershed outside of the Legal Delta with a priority date of 1945 or later.
2. Water rights and claims on the following San Joaquin River tributary:
- Post-1914 appropriative water rights in the Stanislaus River subwatershed outside of the Legal Delta with a priority date of 1952 or later.
The State Water Board will continue to closely monitor forecasted precipitation and hydrologic conditions in order to issue updates to the curtailment status of water rights and claims in the Delta watershed. The next curtailment status update will be provided by email and web posting no later than December 6, 2022. Please check the Delta Watershed Curtailment Status List for the current curtailment status of each water right and claim in the Delta watershed.
Current analyses do not support curtailments in the Legal Delta for non-Project right holders. Analyses do indicate some unavailability for Project rights in the Legal Delta and the Stanislaus River subwatershed. However, based on the Coordinated Operations Agreement (COA) for the Projects, curtailments will not be implemented for Project rights in the Legal Delta if unavailability at the watershed scale is only indicated for some project rights in recognition of the COA’s provisions for sharing limited Project supplies. Term 91 curtailments will continue to apply, to the extent those curtailments are still in effect, to rights within and outside the Legal Delta containing Term 91.
Today’s update considers observed water supply data and forecasts from the California Nevada River Forecast Center (CNRFC) that were updated on December 2, 2022. The 50 percent exceedance water supply forecast was selected to determine curtailments at this time. Demand data informing today’s curtailment status update are based on reported diversions from 2018 as updated through an ongoing QA/QC process. Demand data informing today’s update do not include reported projections of demand submitted under the enhanced reporting provisions of the emergency curtailment and reporting regulation for the Delta watershed because those data are still under review.
The determination of water unavailability used to inform curtailments is based on the Water Unavailability Methodology for the Delta Watershed. The data used to support curtailments and other relevant information are available on the State Water Board’s FTP site. To access the documents posted on the FTP site, please email Bay-Delta@waterboards.ca.gov to obtain login credentials.
Water right holders and claimants are responsible for monitoring their curtailment status online on the Delta Watershed Curtailment Status List. Notice of changes to curtailment status will not be mailed. For those with limited internet access, a pre-recorded curtailment summary can be heard on the Delta Curtailment Status phone line at (916) 323-4643.
For more information about drought in the Delta watershed, please visit the Delta Drought webpage. For more information about curtailment compliance and responses to the Initial Orders Imposing Water Right Curtailment and Reporting Requirements in the Sacramento-San Joaquin Delta Watershed, please visit the Curtailment Compliance and Responses webpage. The Curtailment Compliance and Responses tracker is updated regularly and can be filtered to see the latest changes. If you have any questions, you may send an email to Bay-Delta@waterboards.ca.