Duluth may look to wean itself off road salt

Mar 08, 2023

DULUTH — It may come as no small surprise that given the city's hills and often-formidable winter weather, Duluth goes through a lot of road salt each year, with a five-year average annual consumption of nearly 15,600 tons. But some local officials are suggesting the city had best consider switching to a lower-sodium diet.

"We have the ability to change our current state that we are in for the better for the environment and for the people in our community," said Geoff Vukelich, operations coordinator for Duluth's street maintenance department.

Ryan Granlund, Duluth's stormwater coordinator, noted that road salt is far and away the biggest contributor to three local designated trout streams being designated as "impaired" waterways. Those streams include Miller, Kingsbury and Keene creeks.

And additional local trout streams also are on the cusp of impairment, according to Granlund, who said Duluth's Coffee, Merritt, Chester and Tischer creeks stand "at high risk of impairment," unless the city changes its ways.

"We need to understand that we’re having a big environmental impact, and we’re getting to the point where we’re going to be putting the next red marks on the map," Vukelich said.

ADVERTISEMENT

It doesn't need to be that way, however, according to Vukelich.

"We have the ability to change this. I personally believe we could easily cut our use of road salt by 20 to 30%. But we need help. We need funding, and we need support from you folks," he told the Duluth City Council at a May 18 presentation.

Vukelich suggested Duluth should be a regional leader, but is instead being "left behind in the dust" by St. Louis County, following its $11.5 million investment in new equipment. He explained that the updated snow plow fleet has enabled the county to branch out into applying different types of sodium solutions that reduce salt consumption and runoff, compared with the granular salt and sand mixture that Duluth primarily uses.

While Duluth, as a port, benefits from some of the lowest-cost salt prices to be found, Vukelich said the city still spends about $1 million on salt and sand each winter.

With its current fleet of plows, Vukelich said Duluth remains unable to effectively change course.

"Currently, we have almost 50% of our units that are over their life cycle. We averaged five units out of service every day all winter long, and we still did a great job," he said.

Granlund said it takes just one teaspoon of salt to permanently pollute five gallons of freshwater, noting that the mineral can't be removed effectively and does not naturally degrade. He said salt-laden water molecules are heavier and often sink to the bottom of a water body, impairing water quality, damaging vegetation and even disrupting natural cycles. He pointed to studies of some particularly salt-laden lakes in the Twin Cities metro area that have been found to no longer turn over with the seasons, as would be the norm in unimpaired waters.

Vukelich suggested the city of Duluth could be more strategic in its use of salt, applying it when conditions make such treatment most effective. He said the city also could consider a chloride-management ordinance that would regulate the use of salt by others, including big-box retailers intent on clearing massive parking lots of snow and ice.

ADVERTISEMENT

He advised that the city likely will need to make some significant investments to up its own game, however.

"Our equipment is old and outdated, and we’re doing the best we can with it. But if we can get new equipment, then we can start branching out to hose additives which would overall lower our sodium chloride use. So, that's where we need to concentrate," Vukelich said.

Vukelich and Granlund's May 18 presentation was meant to bring their concerns to the City Council's attention and to educate the public about the issue. They intend to revisit the council at a later date to discuss possible next steps, the likely costs involved and the benefits, including cost savings, that could arise from investing in new equipment.

"I think it was really important to have this educational piece preceding any policy discussion," said 2nd District City Councilor Mike Mayou, of the presentation. "We’re still trying to figure out how we can do a better job of keeping our streets safe while taking care of the environment."

ADVERTISEMENT