Risky arsenic levels hit dwindling water supply in Colorado’s San Luis Valley
When John Mestas’ ancestors moved to Colorado over 100 years ago to raise sheep in the San Luis Valley, they “hit paradise,” he says. “There was so much water, they thought it would never end,” Mestas says of the agricultural region at the headwaters of the Rio Grande. Now decades of climate change-driven drought, combined with the overpumping of aquifers, is making the valley desperately dry — and appears to be intensifying the levels of heavy metals in drinking water. … During drought, the number of people in the contiguous U.S. exposed to elevated arsenic from domestic wells may rise from about 2.7 million to 4.1 million, Lombard estimates, using statistical models. Arsenic has been shown to affect health across the human life span, beginning with sperm and eggs, James says.