Russian River delta
Russian River Delta leading to Pacific Ocean. Photo: Gerald Peplow /

By Scott Hamilton, President, Hamilton Resource Economics

The Public Policy Institute of California (PPIC) is a nonpartisan group that provides independent, objective analysis and perspectives on some of California’s toughest issues. In recent years, much of their water focus has been on the San Joaquin Valley. On February 15th of this year, two of their senior representatives testified before the California State Assembly Water, Parks, and Wildlife and Local Government committees regarding the Sustainable Groundwater Management Act (SGMA) and its implications for the Valley.

PPIC’s projections of economic impacts in the Valley with and without water trading, but questions surround the feasibility of water trading when SGMA forces water districts to keep supplies local. (Image: PPIC)

Their presentation was a summary of several earlier reports on the San Joaquin Valley. Their estimate of the historic (1988-2017) water shortage in the Valley was two million acre-feet. They indicated that the continuing overdraft has led wells to go dry, lands to subside thereby damaging infrastructure, and poses risks to water quality and ecosystems. Two million acre-feet is a very large number. The State Water Project, with its several major reservoirs and customers with deep pockets, only delivers slightly more than that, on average, each year. And as bad as that number sounds, it is too low for several reasons. Because it is based on historical conditions, it does not consider the need to meet new environmental demands such as flows for the San Joaquin River Restoration Program or in-stream flows to meet State Water Resource Control Board requirements. It does not consider the impacts of climate change on delta exports, estimated to be 350,000 acre-feet per year. And it does not include the increase in orchard acreage that the Valley has experienced in recent years. Adding those other considerations moves the shortage closer to three million acre-feet. 

PPIC felt that about a quarter of the deficit (500,000 acre-feet) could be met by expanding groundwater recharge programs. That number is considered high by many water managers in the Valley. For Kern County, it is misleading, but not intentionally so. In 2017, one of the wettest years on the Kern River, no Kern River water left the county. Rather, it was all diverted to groundwater recharge or surface uses, and the three water districts along Poso Creek, Cawelo, North Kern and Semitropic, have invested significant resources in expanding recharge facilities to capture its high flows. There is essentially no uncaptured local water in Kern County. The major area for capturing high flow water in the Valley is north of the Chowchilla River where uncaptured water is more abundant and recharge facilities are less developed. 

While the Groundwater Sustainability Agencies located in the Valley have plans to address the shortages, DWR has found that nearly all of those plans were “incomplete.” PPIC suggested recurring and troubling themes in the plans: a tendency to underestimate historical overdraft while overestimating the availability of new supplies, and a reluctance to take ag land out of production. PPIC projected that 500,000 acres of farmland would come out of production by 2040. That was half the number that Dr. David Sunding, a professor at UC Berkeley, had estimated. Sunding had also estimated the annual impact to the Valley was a loss of $7 billion and 65,000 jobs. PPIC’s estimate was less than half of that, primarily because their acreage retirement estimate was half that of Sunding’s, and PPIC’s estimated impacts were mitigated by water marketing to reallocate water to minimize adverse economic impacts. Within a water district, water markets may mitigate some of the water shortage impacts, but for the most part SGMA has shut down water markets. Water districts are reluctant to transfer water outside of their districts until they know they have a surplus, and with climate change, that determination involves much uncertainty. 

The PPIC report was an honest representation but requires some context. And whether they are correct, or whether the future might be worse than their projections, a future for the Valley where the only strategies are to increase recharging of local water and to take ag land out of production is an extremely bleak one. PPIC is in the process of updating an earlier study that showed that, on average, 10 million acre-feet of surplus water flows out of the Delta to the Pacific Ocean. By State Water Resource Control Board regulation, only 35% of that may be exported—meaning that outflow must still exceed 6.5 million acre-feet even if Delta export opportunities were to increase. The Water Blueprint for the San Joaquin Valley continues to advance the concept of Fish Friendly Diversions—a method for capturing a portion of the available 3.5 million acre-feet while not harming endangered fish, but, as any worthwhile endeavor, that solution is going to need significant financial and political support.

Previous articlePrecipitation Prediction with Miles Muzio
Next articleMinistry Spotlight: StoryRunners