Use Less Salt: City, County Seek To Find Safer, Cheaper Solutions For Icy Roads
By Craig Manning | May 10, 2021
Despite lingering cold temperatures, winter 2020-21 was warmer and less snowy than a standard northern Michigan winter. That milder weather helped the City of Traverse City and Grand Traverse County reduce road salt usage significantly – good news for everything from municipal budgets to the environment. But while both the city and county are working to minimize road salt usage more permanently, critics suggest that salting roads in northern Michigan has already had dire consequences for local bridges, roads, and watersheds – and that finding a way to eliminate salt usage entirely might be necessary to preserve infrastructure and protect environmental health.
Salt is used on roadways in the winter because it lowers the freezing point of water, thus preventing ice from forming as temperatures dip below 32 degrees. It’s highly effective at keeping roads safer for drivers -- but it’s also highly corrosive and can cause spalling and scaling to concrete and other surfaces.
Over the past several years, local photographer John Robert Williams has used a photo series to document the destructive effects of salt, particularly to Traverse City bridges. Williams tells The Ticker he was inspired to track the issue in part because of his father, who worked at Dow Chemical.
“His job was to sell Dow deicers to the road commissions in the State of Michigan,” Williams recalls. “And the whole reason that Dow Chemical got its start was, before refrigeration, people used salt to cure and preserve their meats. But as scientists do, they find different applications for things. And so they perfected this whole business about making salt for reducing the ice on roads. But as the engineers and the scientists and the chemical engineers told my dad – and he repeated this to me when I was a little kid: ‘When they find out what this stuff does, there'll be hell to pay.’”
Williams says it’s easy to observe “the ravages of salt” in Traverse City, from corroded metal bridge railings to pothole-ridden streets to browned and dead pine trees along local roads. He points to the West Front Street Bridge (pictured) as a good snapshot of what salt can do to infrastructure over time.
“And when you get underneath the bridge, you can see the concrete spalling underneath that arch,” he says. “It’s just amazing how much of that bridge is gone, just from salt being poured on it.”
Salt spalling occurs when dissolved salt flows into porous building materials (such as concrete) or into existing crevices in surfaces and then crystallizes as the surface dries and the water evaporates. As the salt expands, it puts stress on the material, causing flakes (or “spall”) to break away from the surface.
Salt can also pose a risk to local rivers and lakes – something the Watershed Center Grand Traverse Bay monitors actively. According to Heather Smith, Grand Traverse Baykeeper for the Watershed Center, road salts that make their way into local waters “can cause reproduction and growth issues in aquatic life, or even fatality.” She says water quality monitoring programs throughout the midwestern and northeastern United States have been studying the impact of road salt on freshwater systems, with findings indicating elevated chloride levels in waters near urban areas.
The good news, Smith tells The Ticker, is that chloride levels in Grand Traverse Bay are generally low. The bad news is that the area also has several “urban streams” that may be spiking in terms of chloride. The Watershed Center is working with the Grand Traverse Freshwater Society and Trout Unlimited to monitor Kids Creek “for specific conductance,” which Smith describes as “a rather good surrogate for total chloride in freshwater systems.” Preliminary data from those studies wasn’t severe enough to “raise any red flags, but it certainly showed that there were spikes in specific conductance over the winter months.”
“While we need more data to confirm if [elevated conductance] is a problem affecting aquatic life in our streams, we are certainly watching this issue,” Smith says.
Both the city and the county are taking steps to cut back on how much salt they use. According to Grand Traverse County Road Commission (GTCRC) Manager Brad Kluczynski, GTCRC has been tinkering with its road salt mixtures to maximize effectiveness, keep the salt where it’s meant to be, and cut down on total salt use. These days, what GTCRC trucks drop on snowy or icy roads includes more sand and more brine (a mixture of salt and water that helps salt stick to the road) than it did 5-10 years ago. During winter 2020-21, GTCRC dumped 7,392 tons of salt on the 1,200-plus miles of road it maintains, down from 12,229 tons in 2019-20 – and on the tails of five straight winters where the county’s salt usage exceeded 10,000 tons.
The City of Traverse City, meanwhile, started a new chapter this past winter by adding Beet Heet to its road management arsenal. Beet Heet is a liquid solution made up of chlorides and sugars – including sugar beet molasses – which municipalities can use to pre-wet road salt before laying it down on icy roads. According to Frank Dituri, director of the city’s Department of Public Services, the product is less corrosive and more biodegradable than salt, works at lower temperatures, sticks to the road better, and achieves the same safety effects at lower quantities.
Dituri says Beet Heet allowed the city to drop its salt application rate from more than 350 pounds per lane mile in winter 2019-20 to approximately 200 pounds per lane mile during winter 2020-21 – a 42 percent reduction. It also allowed for a 35 percent reduction in cost: The city spent an average of $14.92 per lane mile for salt application in 2019-20, compared to $9.69 per lane mile this past winter.
Dituri’s goal is to stop using salt altogether. “The industry isn’t there yet,” he says, but he’ll be keeping an eye out for new products and future innovations. In the meantime, he confirms the city will continue using Beet Heet next winter.
Still, Williams thinks it’s time for more drastic changes – especially as the city invests in replacing several bridges, and as other infrastructure projects – from sidewalks to roundabouts – take root in the area.
“The whole province of Québec , they have a rule where, starting December 1, everyone has to have snow tires on their cars or the car is impounded,” he says. “Other places around this world get along just fine with snow on the roads. If you live in Traverse City in the wintertime, you go buy a hat, you go buy gloves, you go buy boots, and you buy a shovel. Well, if you're going to drive your car, you better put snow tires on it. And if you don't know how to drive on snow, then you shouldn't be driving. It's that simple.”
PHOTO CREDIT: John Robert WilliamsComment