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Project aims to add Central Valley water

Issue Date: June 21, 2017
By Christine Souza
In a boat on Millerton Lake, Mario Santoyo, executive director of the San Joaquin Valley Water Infrastructure Authority, identifies the site of the proposed Temperance Flat Dam and Reservoir, which would be built on the San Joaquin River within Millerton Lake. Proponents say the project would provide a number of benefits to the region, including ecosystem improvements and carryover water that could be stored for future use.
Photo/Christine Souza
Fresno County farmer Shawn Stevenson, stands in what was formerly a productive citrus orchard. Following consecutive years without water during the drought, he was forced to remove 500 acres of trees. Stevenson says additional water from the proposed Temperance Flat project would help him and other area farmers.
Photo/Christine Souza

Editor's note: This is the second installment of a three-part Ag Alert® series about large-scale water storage projects applying to the California Water Commission for funding from the Proposition 1 water bond.

Hit hard by chronic water shortages that deepened during the drought, agencies in the San Joaquin Valley have banded together, seeking to build a more sustainable water future.

Backers of the proposed Temperance Flat Dam and Reservoir say the $2.8 billion project would capture and store additional water in the San Joaquin River watershed, creating greater flexibility, relaxing pressure on groundwater and providing other benefits to the region.

"For us, the reality is when dry years hit, they hit hard," said Mario Santoyo, executive director of the San Joaquin Valley Water Infrastructure Authority, a joint-powers authority that would help construct the project. "This is a project that, if operated correctly, can help a larger region—east and west. That is what is drawing the collective together; they see the possibilities."

Long studied by the U.S. Bureau of Reclamation, the project, which could take a decade to complete, is among those competing for a portion of $2.7 billion in storage funding available through the voter-approved Proposition 1 water bond.

To be built within the existing Millerton Lake, which is part of the federal Central Valley Project, the proposed Temperance Flat Dam and Reservoir would be upstream from Friant Dam on the San Joaquin River in Fresno and Madera counties.

"Temperance Flat would add 1.26 million acre-feet of storage to Millerton and, when added to existing storage of 520,000 acre-feet, you have a total of 1.78 million acre-feet, or triple the existing capacity," Santoyo said.

The increased supply of water at Temperance Flat—between 100,000 and 200,000 acre-feet of average yield, depending on the final operations plan—would help the state achieve greater sustainability for a growing population and also function to negotiate water exchanges, Santoyo said.

Sharon McHale, a branch chief for the Bureau of Reclamation Mid-Pacific Region, which operates the CVP, said the project needs more storage to meet current and future needs.

"We have a lot of years where we're short, where we can't provide our full contract amount to contractors in the Friant Division," McHale said.

"We are not providing any water to Westside contractors at this point from the existing (Friant) dam, so it (Temperance Flat) would provide water to two groups of contractors that do agricultural irrigation and are in need of additional supplies and water supply reliability," she said.

The Temperance Flat project's current operations plan, Santoyo said, would assure deliveries are first met for Friant Division contractors and for obligations for downstream deliveries and river restoration before additional water could be stored. Water in Temperance Flat would be divided into storage accounts that would be purchased and managed by project investors. The operations plan also allows for water diversions at the Mendota Pool for Westside water users, he said.

In March, San Joaquin Valley water users signed a joint letter pledging cooperation to develop the Temperance Flat project, including the San Joaquin Valley Water Infrastructure Authority, Friant Water Authority, San Joaquin River Exchange Contractors Water Authority and the San Luis & Delta-Mendota Water Authority. The SJVWIA has a governing board of 10, representing counties, cities, a local Indian tribe and the San Joaquin River Exchange Contractors Water Authority.

Proponents of Temperance Flat and other water projects have less than two months to finalize applications for bond funds. If awarded, bond money would be used toward public benefits of the projects, such as ecosystem, fishery and water quality improvements; flood control; emergency response; and recreation.

The project brings hope to Fresno County farmer Shawn Stevenson, who removed 500 acres of citrus trees after suffering through two consecutive years without water during the drought.

"It cost us a huge investment, it cost us employees. I didn't have water at the houses, we didn't have stock water … it was an agonizing time," Stevenson said. "If we had Temperance Flat, we could potentially have extra storage for those dry years."

Grower-packer-shipper Pat Ricchiuti of P-R Farms in Clovis said he was very much affected by two years without water, noting, "I paid $1,600 an acre-foot to keep a vineyard alive, and I didn't get enough from that 3 tons in what the winery paid me to pay for all of the water, let alone all of the farming."

SJVWIA President Steve Worthley, a Tulare County supervisor, said Temperance Flat would be the only project of its magnitude south of the delta.

If Temperance Flat had been in place this year, proponents said, it would have captured the maximum amount of floodwater to be stored in the system for future use.

"We could have captured a lot of that water this year, and in following years you would be able to carry over some of this Class 1, Class 2 water," Worthley said, referring to the Friant Division water contracting system.

Drinking water supplies would also benefit from Temperance Flat, he said.

"We have communities that rely upon this water, and many of them are disadvantaged communities," Worthley said. "This project is very important to their well-being; it is not just agriculture."

Project proponents said Temperance Flat would also provide surface supplies to allow for groundwater recharge, which would help the region comply with the Sustainable Groundwater Management Act.

"SGMA mandates we put in plans for the overdrafted groundwater basins, so places like Raisin City (that rely only on groundwater), if they don't get some type of surface water and recharge opportunities, they are going to have to start fallowing," Worthley said. "Without this project, especially with (SGMA), we are going to lose a very significant portion of this region's ability to feed this country."

(Christine Souza is an assistant editor of Ag Alert. She may be contacted at

Online extra: Questions and answers about Temperance Flat

Permission for use is granted, however, credit must be made to the California Farm Bureau Federation when reprinting this item.

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