The floor of the Central Valley is slumping, and there is arsenic in the tap water. Now it seems the two problems are connected

Isabel Solorio can see the water treatment plant from her garden across the street. Built to filter out the arsenic in drinking water, it hasn’t been active since 2007 – it shut down six months after opening when the California town of Lanare went into debt trying to keep up with maintenance costs.



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“It’s cruel to be living in a state that’s so powerful, so rich, but we can’t count on clean water,” said Solorio, 51, sipping from a bottle amid her flowers and cactus collection.

Facebook Twitter Pinterest Isabel Solorio stands next to the defunct water treatment plant across from her home in Lanare. Photograph: Alissa Greenberg

Towns across the Central Valley region of California have had tap water arsenic levels above the federal limit for almost two decades, levels that research suggests can raise the risk of a variety of cancers and lower IQ in children. During the same period, locals and scientists have noticed another odd phenomenon: the valley is sinking, at rates as fast as 25cm a year. Now it seems that the two problems are connected.

It’s cruel to be living in a state that’s so powerful, so rich, but we can’t count on clean water

The 50,000 sq km of the Central Valley play an essential role in American life: some 250 crops grow here, about one-quarter of the nation’s food supply. Agriculture on this scale requires an enormous amount of water, especially as water-hungry crops like almonds have gained popularity. And since the area’s river and rainfall levels fluctuate widely even month to month, farmers say they have no choice but to drill wells and draw aggressively on aquifers.

A 1977 photo from the San Joaquin Valley shows subsidence over time as a result of groundwater pumping. Photograph: USGS

Over the past century, groundwater levels in some places have fallen as much as 200 meters during drought conditions, according to the United States Geological Survey. The subsequent changes in water pressure alter underground architectures, leading to a sometimes-surreal slumping of land by as much as 10 meters.

Around Lanare, telephone poles tilt precariously as the land under them shifts and once-sturdy agricultural wells stand on spindly legs that were buried before the ground receded. At the Delta-Mendota canal nearby, the land has dropped some 3.5 meters over 80 years. Boats once easily passed underneath the canal’s bridge; now the water laps at the bridge’s concrete sides, threatening to spill on to the road.

The same subsurface change in pressure can suck arsenic out of layers of clay and into groundwater, like a sponge being squeezed, said Dr Scott Fendorf, a professor of earth science at Stanford University and a co-author of a new study on the subject. “When we’re overdrafting the aquifer, the two things happen simultaneously.”

Living with arsenic-contaminated water today is easier than in the days when Maricela Mares-Alatorre and her family had to drive nearly 40 miles to the closest grocery store to buy water. Now, Mares-Alatorre and her family receive 30 gallons of water a month from the state, delivered to their home in Kettleman City, not far from Lanare.

For four people, that’s just barely enough, Mares-Alatorre said, but the situation requires an unusual calculus that people with a steady supply of clean water never need to consider. Is boiling pasta safe in tapwater, since the pasta will only briefly cook in the water? What about cooking beans that sit in water longer?

Once, Alatorre said, her daughter wanted to paint and unwittingly used some of their bottled water for her project. “No, that’s not for watercoloring, that’s for drinking!” she remembers shouting. She worries about her daughter’s other contact with arsenic-laden water, in the shower for instance.

Solorio added that bottled water has become a way of life for her and her community, but it complicates everything – figuring out how to transport it, how to make sure there is enough for emergencies, how to explain to her grandchildren why they can drink tap water when they travel outside town but not at home. “It’s uncomfortable,” she said. “It’s frustrating.”

Facebook Twitter Pinterest Boats were once able to pass under the bridge over the Delta-Mendota canal. Photograph: Alissa Greenberg/The Guardian

Several years ago she helped found a group organizing for clean water and other amenities, Community United in Lanare. The group has faced criticism for its activism from an agricultural industry fiercely protective of its water use. Solorio and her husband have both worked in agriculture, and they emphasize the need for cooperation and compromise in finding solutions to the subsidence and arsenic contamination.

A set of government regulations to guide water use would be a start, she said – such as new state rules limiting aquifer use that will be implemented between 2020 and 2042.

With help from Solorio and Community United in Lanare, two new wells are in process in town, and initial water tests show arsenic levels within acceptable range. Until then, she’ll continue to care for her flowers with the water that comes out of her tap. So far, they’re still growing.

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