Bad News: CVP and SWP Plan to Drain CA’s Largest Reservoirs

The Bureau of Reclamation and Department of Water Resources plan to allocate approximately 5 million acre feet of water this year—as long as California allows them to effectively drain the two largest reservoirs in the state, potentially killing most or nearly all the endangered winter-run Chinook salmon this year, threatening the state’s resilience to continued dry conditions, and maybe even violating water quality standards in the Delta.

The Bureau of Reclamation recently announced initial water supply allocations for Central Valley Project contractors that would deliver nearly four million acre feet of water this year (primarily for large agribusiness in the Central Valley), and the California Department of Water Resources has previously announced that it would deliver close to another million acre feet of water this year (about half of which would primarily go to irrigate rice along the Feather River). Five million acre feet is a lot of water, especially in a very dry year—roughly enough to supply the City of Los Angeles for 10 years.

But these water allocations would come at a steep cost, because they depend on draining California’s two largest reservoirs (Shasta and Oroville Reservoirs) to levels on par with—or even below—the devastating drought years of 2014 and 2015. This poses an unacceptably high risk of killing the vast majority of endangered salmon below Shasta Dam this year, like in 2014 and 2015 when endangered salmon runs on the Sacramento River downstream of Shasta Dam were decimated by lethal water temperatures, as the tables below show:

Shasta Reservoir (Bureau of Reclamation):

Year     End of April Storage End of September Storage Estimated Temperature Dependent Mortality of Endangered Winter-Run Chinook Salmon
2014 2.41 million acre feet (“MAF”)  1.17 MAF 77%
2015 2.66 MAF  1.60 MAF 85%
2021 (Est) 2.481 MAF  1.407 MAF ??

Oroville Reservoir (Department of Water Resources):

Year End of September Storage
2014 1076 Thousand acre feet ("TAF")
2015 1057 TAF
2021 (est) 794 TAF

Draining California’s major reservoirs won’t just kill off the salmon that spawn below these dams and threaten thousands of fishing jobs that depend on healthy salmon run; it also means that California will be very badly unprepared if 2022 is also dry.

And to make matters worse, there are widespread rumors that DWR and Reclamation are considering petitioning the State Water Resources Control Board to waive water quality standards in the Delta, because these agencies refuse to plan for the inevitable drought years in California. Instead, they appear to simply expect to be allowed to break the rules during droughts, as they did in 2014 and 2015, which caused devastating impacts to our native fish and wildlife. In 2016, the State Water Board concluded that,

However, the State Water Board also determines that the status quo of the past two years is not sustainable for fish and wildlife and that changes to the drought planning and response process are needed to ensure that fish and wildlife are not unreasonably impacted in the future and to ensure that various species do not go extinct.

—SWRCB, Water Rights Order 2015-0043

In the past few years, NRDC and our partners have written letters to state and federal agencies urging them to analyze the effects of waiving water quality standards in future droughts like they did in 2014 and 2015 as they adopted new permits, but DWR and Reclamation refuse to do so.

Even worse, unlike in the prior drought, DWR and Reclamation are proposing these disastrous operations after a single dry year in 2020 and only two years after these reservoirs were filled in the wet year of 2019. While DWR requires urban water providers to plan and prepare for 5 years of drought (Water Code § 10635(b)), DWR and Reclamation are wholly unprepared for even 2 consecutive drier years, and they are planning to drain these reservoirs after a single critically dry year.

            Last Drought                 Present  
Year      

Water Year Type (Sacramento Valley Index)

Shasta Reservoir End of September Storage

Year    

Water Year Type (Sacramento Valley Index)

Shasta Reservoir End of September Storage

2011  Wet 3.34 MAF 2019  Wet 3.42 MAF
2012  Below Normal 2.59 MAF 2020  Dry 2.19 MAF
2013 Dry 1.91 MAF 2021

Critically Dry (Est)

1.407 MAF (Est)
2014 Critically Dry 1.17 MAF 2022 ?? ??
2015 Critically Dry 1.60 MAF 2023 ??

??

If there’s any good news to share, it’s that the Metropolitan Water District of Southern California has record levels of water in storage this year, thanks in part to a diverse portfolio of water supply sources and improving water use efficiency that allowed them to store water since the last drought ended. And going forward, MWD and other water agencies have huge opportunities to further reduce reliance on the Bay-Delta through investments in sustainable water supply projects like the water recycling, and continued improvements in water use efficiency that reduce demand for water.

But fish and wildlife won’t have the luxury if these allocations proceed. The announced water supply allocations—based on water project operations that would almost certainly devastate our native fish and wildlife and leave California poorly prepared if 2022 remains dry—are outrageous and unacceptable. They can only be met by relying on the Trump Administration’s blatantly unlawful biological opinions, which were the product of scientific misconduct, political interference, and bias (as discussed in this recent news story written by reporters with the Guardian and Sacramento Bee). These biological opinions allow Reclamation to drain upstream reservoirs and kill 100% of the endangered salmon this year, which is why we’ve called these biological opinions a plan for extinction and have, along with the State of California, challenged these biological opinions in court.

There’s always a chance that we get bailed out with a Miracle March, but there aren’t a lot of storms in the forecast at this point. We can all hope for rain even as we plan for dry conditions.

While the proposed operations of the state and federal water projects look like a repeat of 2014 and 2015, that will only be the case if these agencies get away with it. We believe most of California learned its lessons from the disastrous water operations of 2014 and 2015, even if DWR and Reclamation steadfastly refuse to. We hope the State of California will prevent a repeat of that disaster this year. 

About the Authors

Doug Obegi

Director, California River Restoration, Water Division, Nature Program

Join Us

When you sign up you'll become a member of NRDC's Activist Network. We will keep you informed with the latest alerts and progress reports.