Editor’s Note: This article was updated on February 24, 2023, to reflect approval of the petition and additional information regarding state actions associated with the petition.
Following the driest three-year period on record, California experienced one of the wettest three weeks in January. But now those extreme wet conditions have activated a water quality standard in the Delta that, coupled with the extended dry period since then, could result in a sharp reduction in the amount of water that can be retained or moved into storage for both the State Water Project (SWP) and federal Central Valley Project (CVP).
The Department of Water Resources (DWR) and the U.S. Bureau of Reclamation (Reclamation) are working in real time to operate the state’s water system to maximize water supply while protecting species and the environment. However, California continues to experience unprecedented swings in weather impacting water management operations.
Because of these extreme weather swings, DWR and Reclamation are taking proactive measures to manage the state’s water supply to store and capture more water in preparation for a return to hot, dry weather in the next two months.
Both agencies submitted a Temporary Urgency Change Petition (TUCP) to the State Water Resources Control Board requesting approval to modify a single compliance point for compliance with Delta water quality conditions specified in their water right permits, while proposing measures to avoid impacts on Delta smelt along with other State Water Project actions to protect listed species. The petition covers operations from February 1 to March 31. DWR and Reclamation will continue to implement all other state and federal endangered species permit protections during the duration of the order. That petition was approved by the Water Board on February 21.
DWR and Reclamation typically would seek this kind of change during extremely dry conditions. But the swing to extremely wet conditions after extremely dry conditions has created challenges, and the projects are acting to enable additional opportunities for water storage north and south of the Delta while maintaining protections for species.
The request for the TUCP follows protective actions taken by DWR and Reclamation under state and federal endangered species permits in late December and early January, including the “first flush” action to reduce pumping and allow storm runoff to flow through the system for the benefit of native fish species. Recent monitoring information shows the actions worked as intended, with key fish species moving downstream of the Delta and away from the direct influence of the SWP and CVP pumps. In fact, as of February 23, DWR has zero confirmed incidents of winter-run Chinook salmon being recovered in the Delta pumps.
The water quality and water right permits that dictate SWP and CVP operations require certain water quality conditions to be met at specific compliance points in the Delta to provide for favorable conditions for endangered fish species. In consultation with the Department of Fish and Wildlife, DWR and Reclamation are requesting that the State Water Resources Control Board temporarily move the compliance point in the projects’ water rights permits from Port Chicago six miles east to Chipps Island. The new compliance point remains within the Suisun Bay, a valuable rearing habitat for listed species, and is anticipated to ensure water quality sufficient to protect beneficial uses.
These actions will allow DWR and Reclamation to move and retain more stormwater and runoff in the state’s reservoirs in preparation for continued dry periods. A total of approximately 300,000 acre-feet would be saved for later use by the State Water Project alone. Storage gained under the order provides additional flexibility for further fish protection actions in spring. For example, Feather River pulse flows may be considered to enhance spring-run juvenile salmon survival during March and April.
While the January storms provided much-needed rain and snowfall, they did not end drought conditions for much of the state and California remains in a drought emergency. Regions that rely on the Colorado River system face increasingly severe water shortage conditions, and groundwater basins that serve communities in the Central Valley will not recover quickly from back-to-back years of drought and chronic overdraft.
DWR will continue to work with federal and state partners to be proactive and respond in real time to balance multiple water supply needs.