Anyone who has been on campus this past week has likely experienced the result of the varying temperatures — ice. Many students have fallen victim to the slick sidewalks and lost their footing more times than they can count.
While University Health Services advised “walking like a penguin” to avoid falling in an Instagram post Feb. 7, the tip seems to have evaded students as complaints about slippery sidewalks continue to escalate on social media. Students believe the solution is simple: UW needs to apply more salt on campus walkways.
There is a lot more at stake than poor footing or university penny-pinching, however. Assistant professor Hilary Dugan from the UW Center for Limnology said road salt usage has immense impacts on freshwater environments.
“Chloride pollution is another example of human’s impact on the environment,” Dugan said. “High salt loading into lakes affects aquatic species and drinking water.”
UW faces backlash after holding classes despite citywide snow emergency
Dugan said when salt is spread onto roadways and walkways, it does not stay in one place. Water runoff carries it to water sources like Lake Mendota.
Chloride levels in Lake Mendota have increased 48 mg/L in the last 78 years. Dugan stressed that if more changes are not made to salt usage in the Madison area, the chloride concentration will reach toxic levels. Dugan also noted that while the chloride levels in Lake Mendota have increased significantly, Lake Monona and Lake Wingra have experienced even greater increases.
Emeritus professor of integrated biology and former director of the Center for Limnology John Magnuson said that while chloride is not thought of as toxic, the Environmental Protection Agency has standards in place to describe which chloride concentration levels become toxic to organisms. Essentially, if fish and other wildlife are exposed to chloride concentration above these levels for too long, they will die, Magnuson said.
While the lakes in Madison are on track to be in serious trouble in the following decades, there are other areas that are experiencing these dangers now. Magnuson said shallower water habitats, such as marshes or wetlands, experience higher levels of chloride concentration than larger bodies of waters do.
“There’s a little bit of runoff and a big volume of water so that the salt concentration is very diluted, and even that, eventually, will be a problem,” Magnuson said. “But if you have really shallow water, where storm sewers are running into it, like the 1918 Marsh, or the salt pile is stored next to it, they’re shallow enough that the concentrations are much higher in the water than they are in Lake Mendota.”
While the environmental impact of salt is alarming enough, there are more effects even closer to home — the faucet. Both Dugan and Magnuson said that road salt usage is also playing a huge role in the quality of Madison’s drinking water. Poor water quality resulting from road salt usage has already caused at least one well in the Madison area to exceed the sodium limit in place by EPA guidelines. According to a water quality report put out by MWU, Well Unit #6 of Dane County had a sodium level of 26 mg/L, six mg/L over the EPA limit for drinking water.
All of the previous negative effects of road salt leaves the UW campus in a tough spot, one that they put a great deal of effort into mediating. Building and Grounds Superintendent Ellen Agnew relayed several initiatives taken by campus, one of which was the broom tractors being used on campus.
“We are able to broom off the snow and not have to put material down. That’s what we try to do and we try to minimize the amount of material we have to use by getting as close to the pavement ahead of time,” Agnew said.
Other measures UW takes that Agnew mentioned are using sand when the temperature is too low to use salt, as well as using salt brine before a storm hits. Salt brine is a salt and water mixture sprayed on to roads and sidewalks before a winter storm. When salt is put down with water, it sticks to the road and is not washed away as easily by water runoff. This makes it more effective and environmentally friendly.
Director of residence hall facilities Mike Kinderman stressed that housing is working 24/7 to ensure housing facility areas are clear for residents. Not only do they have full-time staff on the clock constantly, but student employees are often called in at 6 a.m. to assist during big snowfalls. Kinderman hoped that students understand campus is always trying to maintain safety — but welcomes feedback.
“When you have a campus this size, I do think there’s always going to be some situations that are not great because you just can’t get to everything right away,” Kinderman said. “I just appreciate everyone’s patience. Like I said, I do think it’s always okay to provide feedback.”
Amidst the environmental cost of salt is also the very real monetary cost. Agnew estimated that campus has used over 800 tons so far this year, and even with the contract that UW has with a company, salt costs approximately $70 per ton. This means that UW has spent about $56,000 on salt alone, not to mention man hours. Winter is not over yet, and the numbers will continue to climb.
Kinderman, however, reinforced a key focus of campus and Housing. The mantra of housing is “Badgers Live Sustainably.” UW campus prides itself on its efforts to minimize its effects on the environment. While the monetary cost is large, campus is more concentrated on the environmental costs of salt.
“There is a tradeoff and I do think salt is costly,” Kinderman said. “I think the bigger piece that we consider is really the environmental impact and you always want to think about that when you’re trying to weigh out what should actually be used to make it safe to walk through.”
For more information on how road salt impacts the environment and how to salt responsibly, visit SaltWise.
