A sprinkle on your steps and a dash on the sidewalk may not seem like much. But some environmental researchers say the use of rock salt by consumers to melt ice and snow has as much of an effect on water supplies as municipal use.
Salt, made of sodium chloride, dissolves into the snow and washes down drains — eventually making its way into fresh water, including the Delaware River.
Chris Crockett, director of planning and research at the Philadelphia Water Department, said rock salt only works when applied correctly — and most individuals don’t know how to do so.
“Most highway organizations actually have a certain application rate of what they put down on the streets or roads depending on temperature and situation,” he said. “The average homeowner doesn’t have a standard method of doing that and sometimes they can over-applicate, they can put a little too much down or put the wrong material down.”
To put the salt’s impact in perspective, Crockett suggests multiplying the Water Department’s 450,000 residential customers by one 50-pound bag of rock salt each.
Tracy Carluccio is with the Delaware Riverkeeper Network, a nonprofit advocacy group that protects the rivers protects water quality and habitat. She strongly encourages people to spend a few extra dollars on safe alternatives that can be found at any hardware store. While kitty litter or sand won’t melt the ice, they greatly improve traction.
“When the snow melts and the runoff from your steps or your sidewalk goes into the storm drain, the storm drain carries that runoff,” she said. “Which includes the salt and anything else on the roadway to the nearest waterway, which is either a creek or, in the case of Philadelphia, most likely the Delaware River.”
Carluccio said salt doesn’t just harm water. The excess sodium chloride disrupts plant growth and may damage sidewalks.