Last month the Clinton Administration sent a high level delegation to Mexico City to identify hot spots that could flare up during the presidential elections. But far more than another economic meltdown or ongoing political violence it is environmental decay -- exacerbated by a five-year drought -- that threatens Mexico's long-term stability. As much of northern Mexico turns into a dust bowl, corn farmers are abandoning their farms, sacking government-owned warehouses, crossing the border. An old-fashioned water war looms with the U.S., and maquiladoras are threatened with water rationing. PNS contributing editor Joel Simon's book on the Mexican environmental crisis will be published by Sierra Club Books next year.

MEXICO CITY -- With no rain for five years, hunger and desperation are growing throughout Mexico's arid north. Reservoirs have shrunk to dangerously low levels, the country's best farmland has turned into a dust bowl, and thousands are crossing the border into the U.S.

"The countryside is being abandoned," says Martin Solis, coordinator of the Democratic Peasant Front, a coalition of small farmers in Chihuahua. "The soil is so hard that a plow can't break it."

The drought -- the worst in a quarter century -- is a reminder that the greatest threat to Mexico's long-term stability may not be drug-related corruption or political anarchy but rather environmental decay. While a natural phenomenon, the drought has been exacerbated by limited funds for emergency aid. The social cost, meanwhile, is being paid on both sides of the border.

This year's corn crop has already been lost in much of Mexico's north. Only 12,000 hectares have been planted in Chihuahua instead of the 400,000 in normal years, according to the Democratic Peasant Front, where an estimated 100,000 farmers are out of work. Many have migrated to cities like Chihuahua and Ciudad Juarez or across the border to Texas, Florida, Colorado, Illinois and California.

For those who have stayed behind, the situation is now so dire that hungry peasants have sacked government-owned grain warehouses. Last week a freight train carrying corn was ransacked by 300 people, many of them women and children, who placed cement columns across the tracks to stop the train.

Unable to sustain their herds, ranchers in Mexico have sold millions of cattle, driving down the price of beef in the U.S. Millions of rotting carcasses litter the dusty ranch land throughout northern Mexico. Overall, the loss in agricultural production tops $1 billion, according to the Mexican Secretary of Agriculture.

With water scarce on both sides of the Rio Grande, an old-fashioned water war may be on the horizon. Last October the U.S. government agreed to loan Mexico water if reserves fell below the minimum needed for municipal use. So far Mexico has not asked for the loan, but last month Texas Secretary of State Tony Garza protested that Mexican farmers were siphoning off water from the lower Rio Grande. Mexico promised to curtail the practice.

But Glenn Jarvis, the coordinator of the Water Policy Management Council, an association of water rights holders in the lower Rio Grande Valley, is not satisfied with Mexico's effort. He argues that Mexico has forfeited its rights to the water loan by using part of its allotment for irrigation. "I don't know the basis for that decision, but the loan is no longer in effect."

While municipal water supplies are not in jeopardy at the moment, according to Mexican officials, residents in cities like Chihuahua, Torreon, and Ciudad Juarez report intermittent water outages. Some 2,000 maquiladoras -- assembly plants -- stretching along the border may soon face water rationing. A partial shutdown in the factories could send tens of thousands of new migrants across the border.

Water is a problem not only in the arid north, but also in Mexico City where the rapid depletion of the underground aquifer is causing the city to sink by several inches a year. Erosion, salinization, and over-use of agricultural chemicals destroy millions of hectares of farmland each year. Last year Mexico had the highest rate of deforestation in the world. Battles over degraded farmland are fueling peasant mobilizations from Chiapas in the south to Chihuahua in the north.

While the drought has affected Texas, Oklahoma, and New Mexico as well as the Mexican states of Chihuahua, Sonora, Coahuila, Sinaloa, Tamaulipas and Nuevo Leon, the human impact has been far higher in Mexico where hundreds of thousands of families grow only enough corn to feed themselves even in good years. Farm credit has dried up along with the skies and thousands of indebted farmers are at risk of losing their land to the banks.

"If you travel through the countryside in Chihuahua you'll see sad towns full of old people and skinny animals," says Solis of the Democratic Front. "The grass is yellow, the oaks and pines are dying, and the beautiful landscape of Chihuahua looks like it was burned in a fire."