INNOVATION
Hold the Salt
Researcher Tracks Human Cost of Keeping Roads Ice-Free
universit y geologist sujay k aushal was waiting to testify in Annapolis several years ago about problems caused by the salt spread each winter on Maryland roads when laughter interrupted the hearing. It was directed at the state lawmaker who’d raised the seemingly outlandish topic. “People were like, ‘What is this guy talking about—salt?’” says Kaushal, an associate professor in umd’s Earth Systems Science Interdisciplinary Center and the Department of Geology. “But people wouldn’t be laughing today.” For more than a decade, Kaushal’s research has documented rising salinity in surface water in Maryland and elsewhere, primarily the result of road salt. One of the consequences he warns about—corrosion of water pipes caused
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by the chemical breakdown of sodium chloride ice melter—reared its head in 2015 in Flint, Mich. There, as many as 12,000 children ingested excess lead in drinking water, putting them at risk for damage to their developing brains and nervous systems. Although news coverage focused on testing cover-ups, political recriminations and the potential health effects, salt contamination in the Flint River that caused corroded pipes to leach lead into tap water was the source of the problem. Here’s what’s really scary: Countless miles of aging municipal and residential water pipes nationwide are at the same risk, Kaushal says. Even he and his neighbors in suburban D.C. experienced brown water flowing from their taps in 2015, the result of
salinity spiking in the Potomac River. “It hit me that I have a small child in the house, and there could be elevated levels of harmful metals in the water,” he says. In addition to danger from corroding pipes, saltier water carries other risks. It can compromise entire ecosystems by harming aquatic life in rivers and streams, and it can injure people with sodium-sensitive health conditions like kidney disease. “When I worked for Baltimore City, I received calls a couple times from local hospitals with concerns about the level of sodium in drinking water because of what it could do to patients on dialysis,” says Bill Stack, deputy director of the nonprofit Center for Watershed Protection and former manager of Baltimore’s
ILLUSTRATION BY GABRIELA HERNANDEZ