Latest wave of storms underscores the need for Sites Reservoir

By Sarah March 17, 2023

What a water year it has been. I was driving across the Yolo Bypass on Highway 5 north of Sacramento in November and thought to myself how long it had been since I’d seen it full of water. I missed the beautiful view of what, to me, seemed like a sea of water and birds as I made my way north. At that time, I was a bit pessimistic and thought that it would be a while before we would see that again. Little did I know that we’d all see it a few months later in January and now again in March. The return of flooded fields and full rivers and streams in the Sacramento Valley is a wonderful sight – recognizing that this is also a challenge for communities affected by floods.

After this latest round of storms, we re-ran our analysis of possible diversions into Sites this water year. Based on actual flows in the Sacramento River, we would have been able to divert and store 250,000 acre-feet of water from January 3 to March 13. Most of these diversions would have occurred from January 3 to January 31. No water would have been diverted in February as we got a bit of reprieve from the onslaught of atmospheric rivers and we all dried out a little. Diversions into Sites would have begun again on March 7, after Sites would have implemented another fish pulse protection, in late February/early March to protect out migrating juvenile salmonids.

Based on the California-Nevada River Forecast Center’s updated forecasts, if Sites were operational this year, we would have the potential to divert another 244,000 acre-feet of water over the following 30 days, from March 14 to April 13. This may be a little generous given higher releases out of Black Butte Reservoir for flood control purposes that will likely drop down once this series of storms have passed. There are also forecasts that go past April 13, but we recognize the uncertainties in longer-range forecasts and therefore haven’t forecasted diversions past April 13.

We will continue to update our analysis throughout the spring as more storms come in and as our weather continues to be so dynamic this year. With all of these diversions by Sites, there would be plenty of water in the Sacramento River and Delta for important ecosystem functions. The water would only be diverted under Sites’ highly protective operating and permit conditions and after all other water rights and regulatory requirements are met.

Before the latest storms, all of California was experiencing drought. Now, large parts of the state are no longer in a drought or have conditions that are improving, according to the U.S. Drought Monitor. We have the chance to shape our future and save some of these high flows for dry times, for the benefit of our environment, people and farms. Let’s continue to invest in 21st century solutions, like Sites Reservoir, that can help us adapt to future climate conditions from flooding to drought.