Slick roads, mounding piles, slushy sidewalks, black ice. With the steady coatings of snow and ice New Englanders have been dealing with all winter, it’s easy to get frustrated with local DPW and their methods of snow removal and road safety. They might plow, spray, salt, sand and in any combination. But what is the best approach?
Rock salt is the most common way to de-ice roads in the winter. While rock salt does in fact lower the freezing point of water, making roads less likely to freeze in normal temperatures, rock salt is not the most effective. Rock salt is unlikely to stay where placed. I’m sure we’ve all been behind a rock salt truck one time or another, with hard chunks of salt bouncing off the road, hitting and potentially cracking your windshield and pelting off your hood. The solid rock can also be run off the road, accumulating in areas. The larger chunks are only effective where they are meaning the entire area is not thoroughly treated. Once the salt dissolves in to enough water to coat the roadway, it can get washed away easily. The solid rock salt can also accumulate either in road runoff or in large solid pieces, and when that happens, the local environment changes. The excess salt can take away precious water of an ecosystem and alter the growing conditions for local organisms. Animals can also eat larger pieces of the salt and become ill. And lets not forget it can corrode your sweet ride too!
Sanding offers traction, but like rock salt, it too has some negatives. Not only do we get piles and piles of sand on our streets once the snow melts, it can clog up sewers and the accumulation can kill off vegetation.
So what’s a town to do? Some towns like Scituate and even the city of Boston are turning to brine, a mixture of salt and water, to spray on the streets. The solution is effective at lowering freezing temperature of the roadway like rock salt but by spraying a thin layer over the road helps keep it in place and be more effective. By mixing the salt in the solution also decreases amount of salt needed to keep the roads safe, making brine cost effective as well. The two main issues with brine are correct concentrations of brine and when to spray it. If the concentration mixed has too much water, it can actually cause the roads to be slicker due to freezing. The timing has to be just right because sprayed too far in advance, cars and general road usage will wear off the layer before the storm hits. If sprayed too close to snowfall, it could also make the roads a bit slippery. These seem like pretty minor points when one realizes by switching over to brine and using it correctly, most towns can increase road safety while minimizing damage on the environment.
UMass’s public works uses a spray to keep campus safe from slicks too. It’s the foul smelling, sticky, brown, gooey substance sprayed on every walkway, road and parking lot on campus right before a storm is about to hit the valley. Over the years many rumors have developed about the substance. Some call it soy sauce, and claim UMass buys it in bulk to be used in the dining commons as well. Others think UMass coats their roads in beer, speculating it’s a by-product of the brewing process: a spray made of left over yeast, hops and barley. As weird as that may sound (a college campus spraying beer everywhere), it isn’t entirely wrong. UMass uses a substance called Magic Salt. Magic Salt is rock salt treated with by-product of the distilling process and liquid magnesium chloride. The solution is biodegradable and non-toxic, resulting in a healthier ecosystem.
Written by: Jessica Murphy