MENDOTA, Calif.—When the rain finally came, it stayed three days, turning the rutted roads in this old farm town into a mess of pools and puddles. But calamity is still on its way.

The farms in and around Mendota are dying of thirst. The signs are everywhere. Orchards with trees lying on their sides, as if shot. Former farm fields given over to tumbleweeds. Land and cattle for sale, cheap.

One long weekend of showers amounts to a drop in the proverbial bucket. Everyone here knows that after the driest year on record in California, the Central Valley, one of the richest food-producing regions on earth, is up against what geologists are calling the 500-year drought. Fresno County, the heart of the Central Valley’s San Joaquin Valley farm belt—and the number one farming county in the nation—may lose up to a quarter of its orchards and fields this year for lack of water. President Obama is scheduled to visit Fresno County on Friday to “discuss” the drought.

No doubt everyone in California, and the other West Coast states suffering this drought, will feel the lack of water sooner rather than later. But towns like Mendota (pop.: approx. 10,000), will bear the brunt of it. One of the poorest towns in the poorest region in California, Mendota, Cantaloupe Center of the World, has a poverty rate of over 40 percent. It is also one of a handful of towns in Fresno County almost completely dependent on farming for its lifeblood.

Off-season, by mid-February, idled workers are clearly anxious. Farmworkers and everyone else who waits out the winter for work (truckers, diesel providers, packing suppliers and the like) are nearing the end of the savings they squirrel away during the season. The season starts again in March, April at the latest, but no one knows who will get work when the season begins, or how much.

People are scared, panicked even.

“We hear farmers are not going to plant,” said Segundo Sandoval, who has worked the fields of Mendota for 40 of his 53 years. Staring at a fallow field overlooking the main drag, he recalls when every patch of dirt was planted. Growers began slashing their crops when the recession hit Mendota full blast, in 2009, and a drought choked off water supplies. But if times were bad then, they could be much worse this year.

Mendota already has the worst unemployment rate in California, somewhere between 35 and 41 percent. That doesn’t include the undocumented workers, whose numbers are significant. Chris Schneider, executive director of the Fresno-based Central California Legal Services, Inc., with many farmworker clients, estimates their numbers at anywhere from 30 to 60 percent of the workforce.

On Mendota’s main drag, a sleepy cluster of mom-and-pop shops and dollar stores, men in cowboy hats and boots gather on benches, whiling away the day smoking and talking. Outside the liquor store, more men, holding bottles in paper bags, stand against the wall or loiter in an alley.

Off-season has always brought the idle to drink. But city officials fear that with the drought, half the town’s workers will be out of work even during the high season. Again, that number does not include the undocumented.

The desperation is palpable. With the snowpack in the Sierras, where California gets much of its water, at historic lows, farmers are pumping groundwater to irrigate crops. But that is creating other major issues. The water is salty, for one. Worse yet, all the pumping is sinking the land in the Central Valley, with Mendota at the heart of it.

“Now,” Sandoval said, “some farmers are talking about not planting nothing.” Sandoval said he knows people so worried about their livelihoods they are planning to leave Mendota. He’s worried too, but he’s stuck. “I don’t plan on leaving because I’m already over the hill,” he said. He is also supporting two children at Fresno State University, where tuition is $7,000 a year.

“If it wasn’t for government housing,” he said, “we wouldn’t have enough money to send the kids to college.”

As if life in Mendota wasn’t hard enough, when fields aren’t planted and workers don’t work, crime spikes. Rodrigo Morales, a 30-year-old lifelong Mendota, remembers when the town didn’t need a police force. It formed one after the 2009 drought and recession.

“People were depressed and desperate because of the lack of work,” said Morales, who helps run his family’s Mexican restaurant, Cecilia’s, in the heart of town. “There were DUIs, break-ins, robberies.”

When Morales was growing up, there was so much work, people had no time for trouble. Farm managers would go door-to-door, asking residents if they wanted work. Morales lists a plethora of crops his relatives farmed. “Almonds, broccoli, asparagus, tomatoes, grapes, cotton, sugar beets, bell pepper, corn. I had relatives in Mexico who came up only during the summer,” he said. “When they were ready to go back, there would be more crops, more work.”

Cecilia’s, which has been in business for 25 years, is an unofficial town center, one of the few places where farm owners and farm workers might rub elbows.

It is also the center of local gossip. These days, water—and its politics—is the only topic. Farmers, bolstered by Republican lawmakers and conservative talk-show hosts, blame the Obama administration, Democrats in Congress, environmentalists or all three for the water shortage. Bumper stickers bear “Obama” with a diagonal cross through his name. Road signs shout: “Stop Congress’ Created Dust Bowl.”

The sentiment intensified after a 2009 ruling by a federal judge ordering water authorities to curtail the water being pumped to the Central Valley to help preserve the endangered Delta smelt, a tiny fish that has been disappearing from rivers whose flows have dropped precipitously because of drought.

Obama announced his visit to Fresno a week after the Republican-controlled House of Representatives approved a water bill that would increase the water supply to Central Valley farmers at the expense of the smelt and other fish threatened by the decreased flows to the rivers. The bill was strongly rebuked by California’ two Democratic senators, Barbara Boxer and Dianne Feinstein, who on Tuesday introduced their own drought bill.

Meanwhile, in Mendota, where residents don’t expect the president will stop by, lines form early in the morning twice a week for food handed out at the Pentecostal Church and the town’s youth center.

This is not new. Mendota, even in the bumper crop years, has never been wealthy or middle class or close to it. Until recently, it has always been ignored. Recent press attention is all negative. Lately, some have started calling it the Detroit of California.

This is a sleepy town, with a Latino population of between 95 and 98 percent, with most residents of Mexican origin or ancestry or from Central America. The town was a railroad stop once. But for decades, it has existed much like a border town. It looks like one, with migrant workers who come and go with the seasons, as well as those who plant roots and raise children. Little Monopoly-game-like houses are stuffed with two or more families. Many garages have been converted into rooms, apartments and dormitories for workers.

Mendota is more reminiscent of a Plains Indian reservation than an emptied-out urban center like Detroit. It has the startling poverty and unemployment of the poorest reservations, but it also has the rich cultural traditions and family-centered community. Families go to church together, eat out together, take in relatives who need help.

Some here hope the drought will convince county and state leaders to invest in Mendota in new ways. In recent years, the town has tried to expand its economy with a solar panel factory and a federal prison. So far, neither have made much of a dent.

Sandoval, the longtime farmworker, wonders why all manner of manufacturers, not so dependent upon water, have never given Mendota a shot. “We buy so many products from China or Japan,” he said. “Why can’t companies make an investment here? What’s wrong with Mendota?”