As any doctor will tell you, too much salt in your diet is bad for your health. The same goes for salt on your local roads.
Why? Because most road salt is sodium chloride, the same stuff that fills your kitchen salt shakers. Excess road salt washes into storm sewers, streams, rivers, lakes, reservoirs, and wells. From there it can easily find its way into drinking water.
“Road salt on the road keeps the roads safe in bad weather. Road salt off the road is toxic,” said Bill Kibler, director of science and policy at the Raritan Headwaters Association, a watchdog group serving the Raritan River watershed.
Not only can road salt contaminate drinking water, but it kills plants, ruins soil, and harms the microscopic creatures living in streams and rivers. “It can stress out aquatic life, or it can be fatal to them,” said Laura Kelm, director of water quality for the Great Swamp Watershed Association.
Watershed organizations across New Jersey have advocated for smarter use of road salt in winter. In many places, the message is getting through. One solution is brine, the same type of salty liquid that turns cucumbers into pickles. An increasing number of public works departments are spraying brine on their roadways instead of rock salt. You may have noticed the white lines of dried residue on the pavement before snowstorms.
Brine contains sodium chloride, but diluting it in liquid significantly reduces the amount needed to keep roads ice-free.
According to Kelm, a Michigan study showed that 30 percent of rock salt spread on roads immediately bounces off or is blown away by wind and vehicles. In other words, tons of salt end up in waterways without improving public safety.
The equipment used to mix and spray brine is expensive, said Kelm, but some New Jersey towns are pooling their resources and sharing equipment. Because less salt is used when roads are brined, towns can use the savings to recoup their investment.
Public works departments that can’t afford new equipment for brining can still reduce their use of rock salt through simple actions like turning off salt spreaders when vehicles stop at intersections, and avoiding leaving piles of excess salt along roadsides at the end of a route.
Another alternative is using more environmentally friendly — but more expensive — ice melting chemicals like calcium chloride.
While most salt pollution in waterways is caused by large-scale salt spreading, home use of rock salt can be equally damaging. “For homeowners, I would absolutely recommend avoiding the use of rock salt,” said Kibler. Salt also hurts pet paws, damages leather shoes and boots, causes concrete to crumble, damages floors in houses, and corrodes the metal in cars.
Kibler recommends using calcium chloride or, even better, calcium magnesium acetate. But the best choice of all for driveways and sidewalks may be a sturdy snow shovel and a bucket of sand.
Kudos to the road departments — and homeowners — that have committed to a “low-salt diet” and are keeping pollution out of our waterways.
To learn more about water quality in your town, contact your local watershed organization.
For a directory of watershed groups in New Jersey, go to http://njwrri.rutgers.edu/watershed_orgs.htm.
Byers is executive director of the New Jersey Conservation Foundation (www.njconservation.org).