Road salt: How much is too much? | News, Sports, Jobs
A Marquette County salt truck salts US 41 in Skandia Township during a recent winter season. (diary photo)
LANSING — Volunteers in Gaithersburg, Maryland, are fighting road salt pollution with memorable slogans painted on snowplow blades.
The group is based in the hometown of the Izaak Walton League, a national environmental organization that has established a nationwide program to monitor chloride levels and encourage reduced use of road salt. The group has recorded high levels of chloride in cities in the Midwest and Northeast, with the highest concentrations in Michigan.
Road salt contains chloride, a toxic compound that dissolves in water. If applied to icy surfaces in winter, it can run off into streams and lakes.
Upon receiving test kit results from Salt Watch, the Izaak Walton League compiles the data into an interactive map showing chloride levels at test sites.
Michigan’s high scores are due to a combination of factors, said Samantha Briggs, the program’s director.
Greater Detroit has many paved surfaces that increase water runoff, Briggs said. “The salt has nowhere else to go.”
Michigan’s streams also have alarming levels of chloride due to the winter climate. “The constant cycle of freezing and thawing leads to a high consumption of road salt”, said Briggs.
Salt Watch’s dataset is limited, and many volunteers have submitted readings from Michigan.
According to Briggs, it just seems like the state has the worst chloride problem. “We have a lot of information from Michigan in particular. We are always looking for expansion.”
Salt Watch has a number of partner organizations across the state, including the Outdoor Discovery Center. The Holland Conservancy Group is prioritizing the problem along the Lake Michigan shoreline.
The center’s watershed manager, Kelly Goward, has monitored salinity in lakes and streams near Holland for the past few years. The level in a local stream was 290 parts per million in November, which is considered toxic.
Measurements from a 2021 study show that Lake Michigan’s salinity has risen to 15 times its natural level since the 18th century, but the impact of these high levels is only now being understood.
“It’s one of those things that people have been focusing on lately,” said Goward.
Salt Watch was formed due to growing concern about the adverse effects of salt on ecosystems across the country. “Salt can desecrate the environment” said Abby Hileman, the program coordinator.
Chloride can kill macroinvertebrates and affect natural processes such as seasonal lake turnover. It’s also difficult to filter out of drinking water, and it corrodes metal pipes, potentially exposing people to heavy metals like lead.
“Once salt is in the environment, it never leaves” said Hileman. “It could cause something like the Flint water crisis.”
The Outdoor Discovery Center is looking for solutions, but recognizes that there must be a balance between keeping waterways clean and roads safe in winter.
“We have to ask ourselves which scales are suitable for melting ice”, said Goward.
The group encourages municipalities to reduce road salt and only give it where it is necessary.
Alternatives were also being considered throughout the Great Lakes region, Goward said. A popular alternative is brine, a liquefied form of road salt with less chloride that works faster.
“Most alternatives are not really realistic” said Goward. Brine, calcium chloride, and even beet juice are suggested for road de-icing, but they cost more to store and buy compared to road salt.
Many of Salt Watch’s partners focus on public education and best practices for handling road salt.
“We want people to take responsibility for their ecosystem, we want them to say, ‘This is my stream’.” said Hileman.
Salt Watch has encouraged its volunteers to call for a reduction in road salt use and some have helped bring about changes at the legislative level.
“To see people standing up for themselves is amazing, it’s really empowering.” said Briggs.
The Salt Watch program offers environmental organizations free water sampling kits and provides funds and road salt awareness for awareness programs.
“I want my job to become obsolete” said Briggs.
Daniel Schönherr reports for Great Lakes Echo.
