Drought | California-Great Basin, Region 10

October

The water year begins October 1 each year and ends September 30.
After a third straight year of severe drought, the Bureau of Reclamation’s Central Valley Project begins the 2023 water year with 3.6 million acre-feet of water in storage — one of the lowest starting points in recent years.

November 28 – Reclamation asks its contractors receiving Central Valley Project water for municipal and industrial use to begin planning for potentially extremely limited water supply conditions in 2023.

December 1 – The Department of Water Resources announces an initial State Water Project allocation of 5 percent of requested supplies for 2023.
December 29 – A series of atmospheric rivers require temporary flood operations to begin at Folsom Dam. Releases are steadily increased to make room for incoming flows.

January 1 – Based on recent storm events, Reclamation increases the water allocation for Friant Division Class 1 contractors from 30% to 35% under their 2022 contract year for use through March 1
January 3 – A late December storm event triggers a first flush event, restricting exports to limit Old and Middle River flows to be no more negative than -2,000 cubic feet per second (cfs) for 14 days, which ended on January 16. On January 17, the Turbidity Bridge Avoidance restriction continued this -2,000 cfs flow through January 21st.
January 5 – Reclamation increases releases from Friant Dam into the San Joaquin River and announces the availability of non-storable (Section 215) water available on the American River.
January 26 – The Department of Water Resources increases State Water Project contract deliveries to 30 percent of requested water supplies – or 1.27 million acre-feet.

February 10 – The water supply allocation for Class I Friant Division contractors increases from 35% to 50% for the 2022 contract year.

February 13 – Gov. Gavin Newsom signs an executive order that allows the State Water Resources Control Board to reevaluate requirements for reservoir releases and diversion limitations to maximize water supplies north and south of the Delta.
February 22 – Reclamation announces initial 2023 water supply allocations for Central Valley Project water users.
- Agricultural water service contractors – 35%
- Municipal & Industrial (M&I) water service contractors – 75%
- Sacramento River Settlement Contractors and San Joaquin River Exchange Contractors – 100%, based on the 2023 water year’s determination as non-critical, as defined in their settlement contracts.
- Friant Division – 100% of Class 1 and 20% of Class 2.
- Wildlife Refuges – 100% of contract supply for refuges (Level 2), both north- and south-of-Delta.
The Department of Water Resources increases its forecasted State Water Project deliveries to 35%.

March 7 – With snow levels in the Upper San Joaquin River Watershed outpacing the largest year on record (1983), Reclamation updates the Friant allocation announced on February 22nd by increasing the Class 2 allocation from 20% to 70%.
March 28 – Reclamation increases Central Valley Project 2023 water supply allocations. Irrigation water service and repayment contractors north-of-Delta are increased to 80% from 35% of their contract total. Irrigation water service and repayment contractors south-of-Delta are increased to 80% from 35% of their contract total.

April 20 – Reclamation increases Central Valley Project 2023 water supply allocations to 100% for irrigation water service and repayment contractors north- and south-of--Delta.

June 22 – Reclamation opens Delta Cross Channel gates for duration of summer.