Federal leaders again are talking about enlarging the San Joaquin River's biggest reservoir, a conversation that has officially happened five times in the last 60 years.
Long stalled in political, technical and financial bogs, this is an idea most farmers still like and most environmentalists don't. So what's different now?
This time, an unprecedented drought crisis haunts California, and a multibillion-dollar water bond awaits on the November ballot.
It's time for Temperance Flat Dam and a reservoir twice the size of Millerton Reservoir, supporters say.
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The latest attempt became public in January when federal leaders released a positive feasibility report with a new emphasis on fish restoration and a lower price tag than a 2008 version.
"This process has taken an awful long time to get here," said Mario Santoyo of the California Latino Water Coalition and Friant Water Authority, which represents thousands of farmers. "This is a major relief at this point."
Environmentalists don't agree. They say the hangup is the proposal to tap public money for nearly half the $2.6 billion tab to build the project.
Without public money, this project doesn't work at all, they said.
Federal officials say they have worked hard on the money side of the equation. They trimmed more than $500 million from the 2008 proposal by eliminating a pricey tunnel for a new hydroelectric plant and changing the design of the dam to reduce concrete needed by 20%.
The deadline to comment on the feasibility report is April 18, according to the U.S. Bureau of Reclamation, which issued the document. The expansion would need to clear a thorough environmental review as well as congressional authorization. Construction would take eight years.
In the House of Representatives, Democrat Jim Costa of Fresno last month introduced the "Upper San Joaquin Storage Act of 2014," which would authorize the project.
Temperance Flat Dam would create a 1.33 million acre-foot reservoir to better capture and manage the San Joaquin's average 1.8 million acre-feet of runoff each year, federal leaders say. Each acre-foot is about 326,000 gallons or a 12- to-18-month supply for an average Valley family.
The 1.33 million acre-feet would be combined storage of the current Millerton and the new reservoir created by Temperance Flat.
Millerton Lake's capacity is about 520,000 acre-feet, not enough to store much San Joaquin water to withstand a drought like this one. On top of the irrigation demand for 1 million east Valley acres, lake water also has been used for an ambitious restoration program since 2009.
Even before Friant Dam was completed in 1942, engineers knew Millerton would be too small. In 1952, federal engineers took a serious look at increasing the size of Millerton Lake -- the first of five failed expansion attempts over the last 60 years.
The size was driven by money concerns as the Great Depression ended, federal leaders said. The federal government built Friant as part of the Central Valley Project because the state could not afford it.
Money concerns have not gone away, say environmentalists and one economist. They wonder about the estimate of 48.7% of the project value in ecosystem improvement for fish.
That's the precentage of the project that the public would pay, and it seems too high, said Ron Stork, senior policy staffer for the advocacy group Friends of the River, based in Sacramento.
"Lots of magical thinking," he said.
Economist Jeffrey Michael of the Stockton-based University of the Pacific said he is not a fisheries scientist, but the ecosystem benefit looks overstated to him, too. He reviewed the latest plan at the request of The Bee, and said he saw only small changes in salmon abundance as part of the benefits.
Michael, who is known for assessing water supply projects, added that the feasibility study exaggerates the supply value for farms and cities. In other words, the benefits might not justify the cost.
"My preliminary assessment is that the non-ecosystem benefits have been overstated by $30 million per year," he said.
Michelle Denning, chief of planning for the bureau in Sacramento, defended the the report's analysis, saying it is based on widely accepted factors.
The ecosystem analysis includes the flexibility of using a cold water flow for fisheries. The river restoration program is in the process of bringing back long-gone salmon runs that need cold water.
"The water can be released from selective levels in the reservoir to achieve the temperatures needed," she said.
She added that a larger reservoir has other uses. It could temporarily send emergency water to Southern Californians if a natural disaster cut off the water supply from Northern California. And a steady lake level would improve boating opportunities early and late in the recreation season.
Farmer Kole Upton, chairman of the Chowchilla Irrigation District, said the investment of public money is needed, especially for river restoration.
"Everybody needs this reservoir bigger on a year like this," said Upton. "There's nothing sinful about society investing in the future."