For his water plan to work, Newsom must marshal all key forces

At first glance, Gov. Gavin Newsom’s new water supply strategy might suggest the projects he is proposing will create about 7 million acre-feet of new water, but a closer reading shows that’s not quite true. If every proposed storage facility is built, and the proposed water recycling and desalination projects are also eventually completed, Newsom’s water supply strategy will add about half that much. Even so, his plan is timely and much needed, but making it happen will require unprecedented compromises from California’s powerful environmentalist lobby.

Over the past decade, total water diversions for cities, farms and to maintain ecosystems totaled 75 million acre-feet per year, according to the California Department of Water Resources. Such diversions cannot continue at this volume without new water, because the worsening droughts have imperiled every major source — groundwater, water imported from the Colorado River, and water stored in reservoirs.

“So much of the water conversation in this state has been about conservation, a scarcity mindset,” Newsom said as he introduced the plan on Aug. 11. “That’s a relatively small component of the overall strategy we are introducing here today. Now, we are focusing on creating more water.”

The biggest part of Newsom’s strategy is capture. He has proposed to “expand storage above and below ground.” This accounts for 4 million of the 7 million acre-foot target, but that figure is misleading because it refers to storage capacity rather than annual yield. The “yield” of reservoirs and aquifers is, at best, only about one-third of capacity. 

Reservoirs are never completely emptied, and — especially in the case of in-stream reservoirs — they are rarely filled to capacity. As for below-ground storage, aquifers can only fill slowly, through large, spreading basins that capture floodwater in rural areas or via percolation ponds in urban areas. This means water can only be withdrawn at the rate at which water can be injected into them. 

These storage projects, therefore, are more likely to add around 1.5 million acre-feet of new water a year – not 4 million acre-feet.

Newsom’s plan commits to finally building the storage projects approved by voters in 2014. The biggest part of that plan — the proposed Sites Reservoir in Colusa County — has endured relentless attacks by environmentalists. In an attempt to compromise with them, the design has already been downsized from 2 million acre-feet of capacity to 1.5 million acre-feet.

Opposition to Sites is typical. Environmentalists have consistently opposed new reservoirs in California, even off-stream reservoirs that don’t block the natural flow of a river, as well as expansions of existing reservoirs. They have litigated most proposals to a standstill. Earlier this year, they also prevented construction of a large-scale desalination plant in Southern California. 

Newsom, to his credit, made mention of this, expressing exasperation that environmental regulations have prevented as many good projects from getting built as bad ones. “The time to get these dam projects completed is ridiculous. Permits take years. One of the principles of this plan is to change our permitting, address the regulatory thickets to fast-track these projects, and move things forward.”

But can he get it done?

The other major elements of Newsom’s plan are to:

• Increase reuse of urban wastewater, a relatively uncontroversial idea that could add a substantial 1.8 million acre-feet to California’s annual water supply;

• Conserve another 500,000 acre-feet by persuading city dwellers to rip out lawns, fix leaks and take shorter showers;

• Double the supply of desalinated ocean water and salty groundwater by adding capacity for another 84,000 acre-feet a year. But despite examples of large-scale desalination working all over the world, environmentalist opposition guarantees that desalination will never add more than a small fraction of the water California needs.

Newsom’s call for Californians to move away from a scarcity mindset is a welcome new message. If he can move all these projects forward, it will be a major accomplishment.

______

Edward Ring previously has written about water infrastructure and creating more water for California.