It doesn’t matter whether California is mired in historic drought or soaked from record-setting storms.
The same dinosaur mentality about how the state should capture, store and allocate water never fails to resurface.
In Fresno and the central San Joaquin Valley, where irrigated farming is the primary economic driver, a certain regional hive mind has long prevailed:
● Any water that flows through the Delta and into San Francisco Bay — as opposed to some orchard or planted field — is said to be “flushed to the ocean” and considered “wasted.”
● Therefore, more “surface water storage” (i.e. reservoirs) must be constructed. Including the mothballed Temperance Flat proposal.
Valley residents read variations of this theme on freeway signs and hear it from the mouths of local politicians and farm leaders. Typically with zero pushback and little context from local media.
Writing about these issues from a different perspective, one that doesn’t view “the environment” as a pejorative, often makes me feel like a salmon fighting against the current.
So this time around I enlisted the help of a much bigger fish: Dr. Peter Gleick, a world-renowned expert on water and climate issues and co-founder of the Pacific Institute, a nonpartisan global water think tank.
“Probably the most important thing to understand is not all water that gets flushed to the ocean is wasted,” Gleick said. “It serves a critical environmental and ecological purpose.”
I asked the Bay Area-based scientist what would happen if California’s rivers were prevented from reaching the Pacific, as our local portrayal suggests.
“If we did, the ecosystems would die,” Gleick replied. “All the salmon would die. All the native fish would go extinct. Salt water would flow upstream into the Delta, contaminating the water supplies for much of the state. There are very good reasons why we have to maintain enough river flows. The economic and ecological consequences would be devastating.”
Let’s reinforce that point: Valley farmers depend on fresh water funneled through the Delta for their irrigation. If the Delta gets polluted by salty ocean water, the impact on agriculture would be immense. Letting the rivers flow, to keep the Delta fresh, benefits growers as well.
California must capture more water
Environmental scientists such as Gleick and Valley agriculture interests are in agreement on one key point: California needs the ability to capture more runoff in wet years when it’s available.
But their ideas of where that water should be stored is vastly different.
“We need to store it as groundwater — not in a few more surface storage reservoirs that frankly are too expensive and too ecologically damaging to build,” Gleick said. “We’ve built on all the good dam sites in California, and some not-so-good ones. So what’s left?”
What’s left are marginal locations like Temperance Flat, squeezed between other reservoirs in the over-plumbed San Joaquin River drainage that already contains seven dams upstream of Millerton Lake.
In 2020, proponents of the estimated $3 billion project declined $171 million from the California Water Commission and withdrew its application for additional funding. Meaning Temperance Flat is either dead or “in a holding pattern,” depending on which side you believe.
“Only in wet years would we capture a little more (water) at Temperance Flat, but the cost of that is just too extreme,” Gleick said. “That’s why nobody is willing to pay for it. Farmers aren’t willing to pay for Temperance Flat. The economic cost of building new reservoirs is too high.”
Rather than storing water above ground, researchers are calling for additional groundwater recharge to help replenish underground aquifers depleted from overpumping.
California’s aquifers have the capacity to hold significantly more water (between 850 million and 1.3 billion acre-feet) than can be stored in surface reservoirs (38.1 million acre-feet) where it is also subject to evaporation, according to the Department of Water Resources.
“We could do a much better job at restoring groundwater,” Gleick said. “Even in a wet year, we overdraft groundwater. It’s unsustainable. We can’t keep doing that.”
Underground storage a nebulous concept
It should be pointed out this isn’t a new idea. Agencies such as the Fresno Metropolitan Flood Control District and local water districts have been replenishing groundwater with storm runoff for decades.
But in order to meet the demand for additional storage, according to a Public Policy Institute of California study, the state must expand conveyance systems to transport flood waters into the right basins during rainy years.
Underground water storage can be a nebulous concept, for two primary reasons: First, we can’t actually see the water with our own eyes. Second, at least until the Sustainable Groundwater Management Act came along, pumping was a virtual free-for-all.
Both lead to suspicion and mistrust.
“Groundwater is probably California’s most important water resource,” Gleick said. “The fact that we can’t see it makes it a difficult thing for some people to understand. But we can measure groundwater levels, we understand the geology and we can enhance groundwater storage. There are a lot of field projects trying to do that and we’re learning how.
“But you’re absolutely right. Groundwater storage has to be combined with monitoring. We have to understand who’s using it, and we have to know what they’re using it for. It has to be regulated, and it has to be managed. Like any water resource.”
Gleick believes “small improvements” can be made to enhance California’s surface water storage capacity in rainy years. Those include the controversial Sites Reservoir in Colusa County and expanding Los Vaqueros Reservoir in Contra Costa County.
However, more dams are not the answer. It’s a 20th-century mindset has little acceptance elsewhere in California, outside our own regional fish bowl.
Local politicians and ag leaders know this as well as anyone but are loath to admit it. Instead, they continue to kid themselves — and us — with a false narrative.
“We can’t just say, ‘Build more surface storage’ and not do anything else. That’s just old thinking,” Gleick said. “It’s time to accept reality and do the things that really work and are going to benefit both people and the environment.”