John F. Menvielle has lived all his 95 years in California's Imperial Valley, a desert where few wanted to live, much less farm. But he sweated it out, relying on hard work and plentiful Colorado River water to get him through droughts, floods and pests.

But the future of the $1 billion farm economy in California's poorest county has never been more uncertain. The valley farmers' biggest fear was realized when the Interior Department cut the amount of Colorado water available for Imperial farms and shipped much of it to the coast.

"This is the biggest threat I've seen so far," Menvielle said. "I'll tell you: I'll never give up water to San Diego."

Imperial Valley is fighting back. The water board sued Interior Secretary Gale A. Norton to block her from cutting the valley's water, asserting that its rights are guaranteed under contracts dating back to the 19th century.

A federal judge in San Diego scheduled a hearing on Imperial's request for a preliminary injunction. If the judge doesn't restore the valley's water, farmers' water deliveries will be cut by 15 percent, board members say.

Outside the valley, Imperial is widely viewed as wasteful. About a trillion gallons pour through the valley each year, making it the nation's largest irrigation project. A third is farm runoff that flows into the Salton Sea, California's biggest lake. In 1988, the state found Imperial was wasting water because of excessive runoff.

There's more, critics say. Imperial farms use gravity to water crops, the most inefficient irrigation method. The valley produces mostly hay, a thirsty yet low-value crop. Menvielle's son, John-Pierre, 58, who runs the family enterprise, farms 850 acres of mostly grass, wheat and alfalfa. He uses enough water to supply about 10,000 homes for a year.

Valley farmers say this is the way it has always been, and it is a way of life for which they have worked hard.

John F. Menvielle was 3 months old when his parents, French immigrants, brought him to the valley and raised him in an adobe ranch. Chinese immigrants, who came to build the railroads, worked in the fields. Railroad conglomerates and land speculators ran the valley. San Diego, about 100 miles west, was home to fewer than 20,000.

"San Diego, in the early days, they didn't want the water," Menvielle said. "They had nothing to do with the Colorado River."

In the Imperial Valley, the river meant everything. It flowed through Mexico via earthen canals dug by mule trains. Farmers rode out to the zanjeros, or ditch riders, who lived by the canals, to ask them to open the gate that let water flow onto farms.

Crops could be ruined by floods or drought. Mexican farmers often tapped the Colorado, leaving canals dry. Earthquakes would break up ditches, preventing water from reaching crops.

A short man hobbled by a 1928 high school football knee injury, Menvielle had a knack for farming. He met his wife when he chased down a boy stealing her watermelons. They married 65 years ago and had four sons.

Over time, life got easier. The Hoover Dam and later the All-American Canal ensured a stable water supply. Menvielle acquired land until he had 1,500 acres at one time.

But times have changed. Today, the sprawling coastal cities are demanding Imperial's water.

"Nobody wanted to take our water before, until they started building all those homes in San Diego and Los Angeles," Menvielle said. "Those people don't know nothing about water. They just think you open up the faucet, and that's it."

The Interior Department demanded California sign a deal by Dec. 31 to reduce its overreliance on the Colorado. The linchpin was the sale of as much as 200,000 acre-feet of water a year from Imperial to San Diego. On Dec. 9, the region's water board, under pressure to protect the farm-based economy, rejected the deal.

Shortly after that, the Interior Department cut Imperial's water supply by 11 percent and shipped much of it to Los Angeles and San Diego counties. Farmers pressed the board to fight back, and it did, filing suit in January. But John-Pierre Menvielle wonders whether they can win.

"I don't think the farmers realize the value of this water," he said. "The threat is we are only 140,000 people and there's 17 million on the coast, and they want our water."

Imperial Valley farmer John Menvielle, 95, walks with his son, John-Pierre, right, beside a turnip field on their farm near Calexico, Calif. The family's farming operations began in 1918, and it now owns 1,500 acres of farmland.