David and Sharon Wakefield show the damage a lack of water has caused their farm
In California, irrigation helped turn the state into an agricultural superpower. But as Rajesh Mirchandani reports, lack of water is now turning parts of the state into a poverty-stricken dust bowl.
In California, crops - and dreams - are withering.
Todd Allen has farmed in the Central Valley for 12 years, but this may be his last.
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"Basically what you see here is wheat that died," he says as our feet crunch through a field of wheat, stunted and brittle.
Lack of water has ruined his crop and Mr Allen will harvest just 40 acres (16 hectares) out of 600.
"All I want to do is come out here and raise enough crops to feed my family. Luckily this year I've been able to get through it but if it happens next year it's over," he says.
The 1930s saw economic and environmental problems blight lives
Once a quarter of the US's fruit and vegetables came from this region, a desert landscape made fertile through irrigation. Now vast tracts lie parched, reluctantly abandoned.
Farmers like Mr Allen have been restricted to just 10% of the water they had last year, a restriction that can mean tough choices.
Nearby, David and Sharon Wakefield sacrificed a third of their farm so they could continue to water their valuable almond trees. But the fruit crop isn't enough and they may go bankrupt within months.
Fifty miles (80km) north, the San Luis reservoir that provides Central Valley farms with water is less than 20% full.
It's not just drought. The reservoir is fed from the the Sacramento-San Joaquin Delta, a threatened estuary that is home to a tiny fish called the delta smelt.
Environmentalists say the smelt is essential to the food chain, and that a decline in smelt populations has led to falling numbers of bigger predator fish like salmon and bass.
Late last year, the US government's Fish and Wildlife Service argued that pumping water out of the delta harmed the smelt.
A federal judge ruled water supplies to Central Valley farms should be reduced, in order to protect the fish.
Farmers are challenging the water restrictions in court. They are a well-organised lobby with powerful support.
Governor Arnold Schwarzenegger wants to build more dams to guarantee farm supplies, but that requires money the state does not have and will take time.
Meanwhile farmers believe they are being sacrificed for the sake of the smelt.
Land of promise
In the Central Valley town of Mendota - the self-styled "Canteloupe capital of the world" - many of those that grew crops are now queueing up for handouts.
Pressure on resources is affecting California's agriculture
A community food bank is distributing tinned vegetables and boxes of cereal, a month's supply per family.
Unemployment recently hit 40%. The construction industry in this area collapsed and now thousands of farm workers have joined the recession's tally.
"(There's') no work, no water for jobs," says Alfonso Castro. "I mean people gotta get some kind of food, you know. Cos they can't buy it - they got no money."
"You know, it takes a toll on your pride," says Migdalia Jimenez, "but you've got to feed your kids... you don't want them to starve."
Most of the jobless are native Spanish-speakers, economic migrants who came to California hoping for a better life.
It is an echo of the 1930s, when hundreds of thousands left homes from Texas to Colorado and made the long journey west to pick fruit. Their lands were destroyed by drought and soil erosion. It was called the Dust Bowl.
They saw California as a land of promise.
Now many farmers here blame the government for creating a new dust bowl.
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