The Sonora River stretches from Cananea, a mining town south of the border, to the desert lands west of Hermosillo, the Sonora state’s capital. It meanders for 250 miles and provides water for thousands in some of the most beautiful towns in northern Mexico.

Over the centuries local communities became the cultural core of the region that stretched from Southern Arizona to the middle of Sonora. They are a cluster of rural communities dedicated to small-scale agriculture and cattle.

On Aug. 7, a leaching pond in the Buenavista copper mine, owned by the Grupo Mexico, one of the world’s biggest mining enterprises, spilled 10 million gallons of water contaminated with chemicals, mainly sulfuric acid, iron, cadmium and copper into the Bacanuchi River. Mine officials did not disclose the accident.

Two days later the people in the towns noticed a reddish color in the water; In some places it was a brilliant orange, and it smelled foul. The poisonous sludge flowed into the Sonora River and then south, contaminating municipal and private wells used for drinking and irrigation. The toxic water also killed livestock and fish. Alarm spread in the communities.

The mining company acknowledged the spill, blaming β€œunusually heavy rains,” a tacit acceptance of the fragility, and lack of maintenance of its ponds, but not its liability. The mine offered, as a mere gesture of goodwill, to provide water to the public.

The water provided did not come close to meeting local demand, and in some places the price of a gallon of water went from $1.50 to more than $9. The water provided was barely sufficient for drinking, much less bathing and household necessities.

These towns have traditionally grown corn, wheat, beans, squash, peanuts, vegetables, sugar cane, chiles and pasture for cows. The townspeople sell milk and cheese to the neighboring cities, elotes (corn on the cob), green and red chiles, vegetables, wild oregano and chiltepin that they gather in the mountains. They also sell calves to cattle buyers who fatten them and sell across the border.

The feast of Saint John the Baptist, June 24, is the start of the rainy season, and the beginning of the agricultural cycle.

Since then, for the past two months, the people of the Rio Sonora Valley have been working their fields and growing their crops. Now they have no reliable water and they stand to lose their crops. Livestock are suffering from lack of water. The spill has the potential to be a major disruptor of their rural way of life.

Meanwhile, the Mexican authorities have started to respond in varying degrees. There has been limited assistance to the towns along the river. There is talk of suing the company.

In the meantime, those who live along the river are waiting, skeptically. Information about the condition of the wells that supply the towns and fields has been slow in coming. People want to know if they can drink from their wells, or water their fields; wanting to see if there will be buyers for their products.

And the question remains of remediation of the toxic side effects of heavy metals deposited along the course of the river.

In the towns, people have begun organizing to press the government and the Buenavista Mining Co., to get paid for their losses and to mitigate the damage to their river, to strengthen the dams and secure the leaching ponds to ensure this does not occur again.

That’s the big battle. If they win, we all do.


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Ernesto Camou Healy, a Mexican anthropologist living in Hermosillo, has done field work extensively all over Mexico and specializes in peasant economy and history, food and culture in northern Mexico. He is the author of several books on these subjects.