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Freshwater is Getting Saltier, Threatening People and Wildlife (scientificamerican.com)
Salts that de-ice roads, parking lots and sidewalks keep people safe in winter. But new research shows they are contributing to a sharp and widely rising problem across the U.S. From a report: At least a third of the rivers and streams in the country have gotten saltier in the past 25 years. And by 2100, more than half of them may contain at least 50 percent more salt than they used to. Increasing salinity will not just affect freshwater plants and animals but human lives as well -- notably, by affecting drinking water. Sujay Kaushal, a biogeochemist at the University of Maryland, College Park, recounts an experience he had when visiting relatives in New Jersey. When getting a drink from the tap, "I saw a white film on the glass." After trying to scrub it off, he found, "it turned out to be a thin layer of salt crusting the glass."
When Kaushal, who studies how salt invades freshwater sources, sampled the local water supply he found not just an elevated level of the sodium chloride, widely used in winter to de-ice outdoor surfaces, but plenty of other salts such as sodium bicarbonate and magnesium chloride. He also found similar concentrations of these chemicals in most rivers along the east coast, including the Potomac, which provides drinking water for Washington, D.C. Where did all of it come from? De-icing salts, Kaushal determined, are part of the problem, slowly corroding our infrastructure.
When Kaushal, who studies how salt invades freshwater sources, sampled the local water supply he found not just an elevated level of the sodium chloride, widely used in winter to de-ice outdoor surfaces, but plenty of other salts such as sodium bicarbonate and magnesium chloride. He also found similar concentrations of these chemicals in most rivers along the east coast, including the Potomac, which provides drinking water for Washington, D.C. Where did all of it come from? De-icing salts, Kaushal determined, are part of the problem, slowly corroding our infrastructure.
People still use sodium chloride as a deicer? Around here, pretty much all municipalities have switched to calcium chloride, which deices better than sodium chloride, and tends to not kill everone's grass. They'll only use sodium chloride in dire emergencies - IE massive ice storm at the end of the season and there's no calcium chloride to be had, which is pretty rare.
My Other Computer Is A Data General Nova III.
"by 2100, more than half of them may contain at least 50 percent more salt than they used to" - a total meaningless statistic. Are are going from 1 ppb to 2 ppb, which is essentially a non-event, or from 1% to 2%, which would have serious implications? Doubling without giving a baseline and what that baseline represents is just scaremongering.