"The biggest source of salty freshwater in D.C. and other major northern inland cities is an overapplication of road salt to thaw winter ice, which runs off into rivers or the ground."
"BLADENSBURG, Maryland — Perhaps on another day, the calm waters and green trees on the Anacostia River here would have been an escape from downtown D.C. about seven miles away. But recent heavy rains had pushed discarded bottles and wrappers to the shores. And on this unusually warm May afternoon, hydrologist Sujay Kaushal kayaked through brownish-green waters to investigate if the water quality showed signs of urban life, too.
Performing a routine checkup on its salt content, he dropped a black probe into the water, and watched as his handheld monitor showed a troubling result — the reading showed salt levels were above the federal recommendations for this region.
“Even after a rain, it doesn’t wash away all the salt,” said Kaushal, a researcher at the University of Maryland.
It’s a pattern Kaushal has found again and again: Freshwater ecosystems, like the Anacostia, are growing saltier year-round. That increasing salinity has not only been linked to mass deaths of aquatic life and damaged infrastructure, but some people can even taste it in drinking water. And removing it is no small task — leaving salt to add up in waterways."
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