California’s water system must be prepared for climate change | Opinion

California’s water system, constructed in partnership with the federal government, was built on a predictable weather cycle every calendar year. Throughout the winter, snow piles in the Sierra before it melts in late spring and flows throughout the state just when farms need it most. For decades, this cycle, paired with our world-class water infrastructure, allowed for reliable water deliveries, captured excess flows in reservoirs and efficiently moved supply to refill our groundwater tables. But that rhythm is slowly changing. State climate indicators show the Sacramento River’s peak runoff now arrives nearly a month earlier — in March instead of April — compared with the mid-20th-century record. Looking ahead, the Department of Water Resources projects the Sierra’s April 1st snowpack will shrink by roughly half to two-thirds before the end of the century.

In short, the water is coming sooner, in bigger bursts and disappearing before summer demand even begins, while we fail to store more. At the same time, increased regulations have compounded the state’s water shortages and decreased the reliability of water allocations that can be expected year to year. This year, for example, inflows in Northern California were above average, but some south-of-the-Delta users received just 55% of their standard allocation. These intensifying issues will increase in severity in the coming years if not addressed, but the effects are already seen today. When early runoff flows before it can be used, without sufficient infrastructure to store it, millions of acre-feet simply spill through the Delta and out to sea. The Sites Reservoir Authority calculated that, had the proposed off-stream Sites facility been operating these last two wet years, it would already hold its entire 1.5-million-acre-foot capacity. This water could have been captured and stored between early 2023 and April 2024, while still meeting every environmental flow requirement.

Updated modeling this spring found that Sites could have stored more than 550,000 acre-feet in just five months of the current water year — enough to supply water to millions of Californians each year or to keep tens of thousands of acres of prime farmland in production during the next drought. South of the Delta, the proposed Del Puerto Canyon Reservoir — an off-stream project tied to the Delta-Mendota Canal — could store up to an additional 82,000 acre-feet of new storage every year. Together, these projects would give the state a place to bank the desperately needed resource. This issue should be apolitical, but when the House debated an energy and natural resources package earlier this year that included $2 billion dollars for Central Valley water storage, I was the lone Democrat to vote yes because reliable water is critical to my district and the state. Most of the $1 billion that ended up in the final bill is expected to support the enlargement of existing facilities, such as Shasta Dam and San Luis Reservoir. This is a good start, but many more projects are needed. State leaders on both sides of the aisle must work together to address our current water shortages and prepare California’s water system not only for today’s needs, but for generations to come.

Climate change is not going to wait for us to get our act together, and infrastructure projects cannot be built overnight. Without action today, our farms, wildlife refuges and communities throughout California will be insufficiently prepared to meet our water needs. With additional and strengthened infrastructure, we can capture those earlier flows, convey water where it is needed throughout the state and adapt to the future we know is fast approaching. 

Rep. Adam Gray represents California’s 13th Congressional District and serves on the House Natural Resources Subcommittee on Water, Wildlife and Fisheries.