The stalemate over water reform in California these days swirls around a single word that for decades has ignited conflict among ideological opposites: dams.

Conservatives, including Gov. Arnold Schwarzenegger, insist on building new dams, believing that pooling water in a canyon will end California's thirst.

Liberals first want legal assurances that California will make better use of the water it has – a plea for more regulation that seems pointless to the thirsty.

The age-old conflict remains a key barrier to a water reform package now being tossed around the state Legislature.

Water experts believe there's a solution somewhere in the middle: more water storage and tighter control of that stored water.

There's one proposed dam that tries to fill that middle ground as something more than idle storage. This one is not your traditional dam.

The proposed Sites Reservoir would flood the remote Antelope Valley, which lies northwest of Sacramento near the Colusa County town of Maxwell.

To farmer Mary Wells, the project represents nothing less than the future of agriculture in California.

Wells manages both the Maxwell Irrigation District and Westside Water District, both of which stand to benefit from the project. It would also help her own rice and almond business.

On the other hand, the reservoir would flood the scenic cattle ranch that's been her home for 37 years.

"It's really tough to think about, at this point in my life, losing my ranch," said Wells, 64, who runs the business with her husband, Chuck. "But with most of the family still in agriculture, I want them to have the opportunity to continue. I cannot see how that can occur unless there is another reservoir."

Different kind of reservoir

Sites would be an "off-stream" reservoir. That means it would not block a river, which for environmentalists is the chief strike against most dams.

Instead, the V-shaped valley would be turned into a bowl by building two large earthen dams on its east side and nine smaller dams on its north end.

This bowl would be filled by pumping Sacramento River water from three different sources: the existing Tehama-Colusa and Glenn-Colusa canals, and a new pipeline running due west from the Sacramento River.

This new pipeline would also release water from the reservoir back into the river when it can best alleviate drought and help fisheries. As much as 90 megawatts of electricity could be generated at the same time, though Sites would be a net energy consumer because of the pumping power required to fill it.

Operated in concert with Shasta, Oroville and Folsom dams, Sites could help share Northern California's water delivery burden, allowing existing reservoirs to provide more water for fish habitat.

For instance, Sites could meet water demand normally provided by Folsom in summer, allowing Folsom to save its limited cold water supply for fall salmon and steelhead runs in the American River. This could have a side-effect of stretching summer recreation access on Folsom Lake.

"It's not a traditional reservoir, and it irks me when people think of it as a traditional dam," said Stephen Roberts, manager of surface storage investigations at the state Department of Water Resources, which is studying the project with the U.S. Bureau of Reclamation. "This is really an important tool to provide benefits across California."

Package of dams studied

Three other new dams are being studied in California: one to enlarge Shasta Lake on the Sacramento River; another to enlarge Los Vaqueros Reservoir in Contra Costa County; and a new dam on the San Joaquin River above Friant Dam.

Sites may be the most promising because of its relatively large size and potentially smaller environmental footprint. No major threats to wildlife or habitat have been identified in the reservoir footprint.

"I believe it provides the most diverse set of benefits between the four projects," Roberts said.

Some environmental groups acknowledge the project's potential.

"It could provide additional flexibility," said Laura Harnish, regional director of the Environmental Defense Fund. However, "the focus on it is unwarranted in terms of the range of solutions available. It's not going to fix California's water problems on its own."

Her group is among dozens on both sides of the issue closely following the legislative debate. But what's more important than new dams, Harnish said, is new rules to ensure best possible uses for water now stored behind dams.

That means new conservation mandates, water guaranteed to serve the environment and rules that prevent powerful water interests from controlling the flow.

So far, bills being debated in the Legislature don't include language about specific dams.

Senate leader Darrell Steinberg, D-Sacramento, said he supports funding for the project with the greatest public benefits, based on a competitive review, whether it's groundwater storage or a new dam.

"I know the issue of storage has been a major priority of the administration and the Republicans for many years," he said. "I don't want the debate to focus on just one particular issue."

Pioneer ranch would go

Mary Wells' property is part of the original ranch, settled in 1887 by John H. Sites, namesake for the crossroads hamlet that would be flooded by the reservoir.

There are just 15 families living in the reservoir's proposed footprint, and Wells said their opinions are probably evenly split on the project.

Her two grandchildren learned to ride horses on her 550-acre ranch, and they're now raising about two-dozen Angus heifers to breed next year's herd of beef cattle.

"I love my ranch very much. It's a beautiful place," she said.

The ranch seemed to define California's "Golden State" nickname: Shimmering yellow grasses cropped close by cattle, dotted by mature oak trees, carpet the valley rim on every side.

"I think I'm doing what a lot of Californians need to do, and that's to say, 'Do I want my daughter to continue in agriculture?' " she said. "If it means leaving this place that I've built for 30-plus years, I'll do it. I'm also a Californian, and it's time we started looking at the big picture."

Sites would store 1.8 million acre-feet of water in the Antelope Valley, becoming the state's seventh-biggest reservoir. It would be broad and relatively shallow, averaging about 300 feet deep across 14,000 acres.

Despite its size, the project would yield far less "new" stored water for potential buyers: 622,000 acre-feet on average and 523,000 in drought years, according to DWR estimates. One acre-foot is enough to meet the needs of an average family of five for a year.

The reason for Sites' limited storage prospects is that much of the water it would hold is already contractually held by someone else. The water would just be parked in a new place before delivery.

Groundwater unregulated

Because there is so little water left to capture, many water experts say new dams don't belong at the top of the state's wish list. For more storage, they favor novel ways to capture and manage groundwater, starting with simple monitoring and regulation.

California is the only state that does not regulate or even monitor groundwater use. Those with a well can pump all they they want, whenever they want, without regard for how it affects a neighbor – even if the neighbor happens to be an entire city that depends on groundwater.

"I would be happy to accept a bond measure that asks for money for surface storage if this legislative package included comprehensive groundwater monitoring and management," said Peter Gleick, president of the Pacific Institute, a nonpartisan water-policy think tank in Oakland.

As good as the Sites project might be, Gleick said, the state also needs new rules to ensure it delivers those public benefits, especially if the public is asked to share the estimated $3.8 billion cost.

For instance, DWR planners say Sites water deliveries could be timed to benefit fish. They also say water would be pumped into Sites when energy cost is cheap, then released to generate power when it's expensive – all to help the project pencil out.

But Gleick said these goals could spark new conflict. What if fish need water when energy is cheap? Who decides which is more important?

And if Sites lifts the burden from other reservoirs, what assurances do Californians have that those other reservoirs will operate differently?

In short, they argue, California's water problems can't be solved merely by pooling more water behind dams. New rules for the pool, however, could make dams a better solution.

"It's very unlikely that the way we operate our water systems in California today is going to be valid in the future," said DWR's Roberts. "There's going to be some major policy decisions. People need to start to think about that so they can be in place when we get to 2050."

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