Flush with water, flush with international demand for their products, rice growers should be enjoying their salad days. And they are. Since the early part of the last decade, the total value of California's rice harvest has nearly quadrupled, to $789 million in 2010. The rice boom has helped farmers pay off debt, buy new harvesters and send their kids and grandkids to college.

Yet there's a deep sense of unease in rice country these days, even as farmers start their annual regimen of using crop dusters to drop seed onto fields.

California is at war over water, and rice farmers – because they plant and flood more than a half million acres of fields each year – are the state's most conspicuous users of this finite resource. That means they have a big fat target on their backs for anyone who wants to get their hands on more water.

I spent most of a day Tuesday rambling through rice country, visiting farmers and water district leaders across Sutter and Colusa counties. Nearly all stated they felt squeezed by the forces debating the future of the Sacramento-San Joaquin Delta.

"There's an interesting convergence," says David Guy, president of the Northern California Water Association. "There's this zeal for increased exports from the Delta, and this zeal for more outflow. We are being brought into that debate in a variety of ways."

At play is the Bay Delta Conservation Plan, an effort by water exporters in Southern California and the San Joaquin Valley to get a 50-year permit to continue diverting water from the Delta. Part of their plan is to build a 45-mile tunnel or canal to divert water from the Sacramento River, reducing the need to directly pump water from the southern part of the estuary.

By restoring wetlands and building the canal or tunnel, the exporters hope they will obtain federal and state permission to increase overall water diversions. Yet as they make this push, wildlife agencies and environmental groups are pressing for increased flows through the Delta to help smelt, salmon and other fish.

If both the exporters and supporters of increased flows prevail, that "extra water" will have to come from somewhere. Rice farmers – and other big water users in Northern California – fear it will come out of their hides.

Write this off as a case of aqua paranoia, but the north state has some reason for concern. The exporters from the Delta – particularly the Westlands Water District and Metropolitan Water District of Southern California – have enormous political clout, and seem unwilling to pare back their water demands. The environmental lobby, on the other hand, is backed by the power of the Endangered Species Act, along with some research suggesting that increased flows, at certain times of the year, could improve populations of salmon and smelt.

Both the exporters and the environmental lobby dispute they are making a play for Northern California water. Both say the BDCP will respect the senior water rights held by rice farmers and other users. Yet actions and words by both groups have left Northern California on edge.

Last year, Westlands and other water exporters pushed federal legislation, HR 1837, to get more water from the Delta. Northern California interests attacked the bill as a threat to their senior water rights, forcing Republican Reps. Devin Nunes and Tom McClintock to amend the bill.

In a recent blog post, a policy analyst with the Natural Resources Defense Council celebrated a 2009 state law that, for the first time, requires large agricultural water suppliers to measure how much water they deliver to individual farmers. The writer, Ed Osann of Santa Monica, suggested the law could go far in reducing water usage in Northern California.

"By applying about 5 feet of water to rice fields each year in California's semi-arid climate, rice production draws nearly 3 million acre-feet of water per year, a staggering amount of water roughly equal to the customer demand of five cities the size of Los Angeles," Osann wrote. "So a requirement for water measurement and volumetric billing in rice country could bring new attention to rice production and management practices that might eventually save a significant amount of water."

Rice farmers grimace when they hear or read such comments. Yes, rice requires a sizeable amount of water. Flooded fields demand about about 5.2 acre-feet of water per acre of land farmed. Yet farmers note that more than 30 percent of that water returns to the system after the fields are drained. That leaves only about 3.3 acre-feet of water being used by the rice plants per acre, which is similar to other crops.

Don Bransford, a rice farmer in Colusa County, says he regularly hears complaints that rice growers are using too much water for "low-value crops." Such comments, he says, reveal an ignorance on why rice production started in Northern California.

Early settlers, he notes, quickly learned it was difficult to farm on vast expanses of the Sacramento Valley because of a clay layer under the soil. Irrigation water ended up ponding on the surface, making it impossible to grow orchards or row crops. But it was perfect for rice.

"If I could grow almonds and walnuts, I would have them on every acre," said Bransford. "People don't seem to understand that."

Not all environmental groups are at odds with rice farmers. Bird groups, particularly Audubon, have embraced the huge flocks of waterfowl and shorebirds that flooded rice fields attract. Audubon is now working with rice farmers on new ways to flatten out the berms between rice fields to make them more attractive to nesting shorebirds.

"There is some impact on production," said Al Montna, a rice farmer in Sutter County. "But the enhancements for habitat will more than make up for it."

And that's the thing about rice farmers – they have shown themselves to be adaptable. When air quality districts cracked down on their practice of burning rice straw, farmers phased out the practice. When they had trouble finding markets for rice straw, they started plowing it into their fields and flooding them in winter. The practice allows the rice straw to naturally decompose, and creates habitat for birds.

My guess is rice growers will be willing to change some of their water practices, but they'll want some level of confidence that any sacrifice on their part will really help the Delta's environment and not hurt Northern California's. If the goal is simply to free up supplies for other regions to use, the Delta deal will be dead in the water.

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