The state’s Transportation Agency currently sprays roads with a salt solution that melts snow, but critics say the brine has particularly corrosive effects on vehicles.
“My understanding, from talking to some mechanics … is that (salt brine) adheres to, and sticks, to vehicles more than just what actual salt does that’s applied,” said one of the bill’s co-sponsors, Rep. Mark Higley, R-Lowell.
He said he has heard from mechanics that salt brine is especially bad for mufflers and brake lines.
But officials at the Vermont Department of Transportation say the brine is simply salt and water.
Workers generally make salt brine by combining water with the same salt that is applied to roads dry at other times, said Erik Filkorn, a public outreach administrator at the agency.
Under extreme cold, they sometimes add a substance that makes the solution melt snow and ice at temperatures below where sodium chloride is effective, said the agency’s head of operations, Scott Rogers.
This additive is not corrosive and in fact contains corrosion inhibitors, Rogers said.
Higley and three other lawmakers joined the lead sponsor, Rep. Clement Bissonnette, D-Winooski, in proposing the ban.
H.82 takes up only five sentences. One specifies that the bill pertains only to liquid salt solutions. The salt is most often sodium chloride, it says, but can be calcium chloride or magnesium chloride.
“The (Vermont Agency of Transportation), municipalities, and all other persons shall not use salt brine on any highway, or on any private or public road used by motor vehicles, in Vermont,” reads the third sentence.
Violations of the ban would be enforced as unpermitted water pollution. The ban would take effect at the beginning of July.
The bill would prohibit one of the Transportation Agency’s most-used methods of clearing roads in winter, said Filkorn.
“Salt and brine are an essential part of what we do to fight snow and ice,” he said. Officials say brine allows workers to use less sand and salt while making roads safe.
Filkorn said he couldn’t immediately predict what the AOT might do if the bill were to pass.
According to the agency’s snow and ice control plan, the salt brine it uses consists of a 23 percent solution of salt in water. It is used primarily when road surface temperatures are above 15 degrees Fahrenheit.
The plan stipulates that the agency must add a 3 percent solution of corrosion inhibitors to salt brine.
The agency applied more than 2.27 million gallons of salt brine on Vermont roads during the winter of 2014-2015, according to the AOT’s 2016 fact book and annual report. The agency spread 132,271 tons of salt during the same period and more than 9,600 tons of sand. These treatments were spread over 6,522 lane-miles of road surface.
Salt brine is widely suspected of worsening corrosion of vehicles, although the state says that has not been shown.
An accident in Barre in 2014 illustrated the risks that rusted auto components can pose if not repaired. Investigators said unrepaired corrosion on a car built in the early 1990s contributed to the death of a woman in a crash on a steep hill. The car’s brake lines burst just before or during the accident, investigators said.
The humid climate of Northeast states seems to be hard on automobiles, even without the salt, said Mason Kuhn, head technician at Montpelier’s State Street Gulf.
“Any cars from the Northeast — New York, Maine, New Hampshire — are terrible to work on” because the region’s humidity corrodes their parts, Kuhn said.
The salt only exacerbates this effect, he said.
“Cars are affected by the salt here, in particular, far more than other places,” Kuhn said. “We live in a state that’s really moist, and we use a lot of salt.”
But he wasn’t sure a salt brine ban would make a difference. If the state has to substitute dry salt, that will convert to salt brine when it melts the frozen water and dissolves into it, he said. In the winter, Kuhn said, meltwater that remains on roads is nothing other than salt brine.
Auto owners can combat the effects of road salt by simply washing their vehicles, particularly the undercarriage, Kuhn said.
A more permanent solution is undercoating, he said. That is a protective film sprayed onto the bottom of an automobile that shields the chassis and components from corrosion.
“Regardless of where you get it done, if someone does a half-decent job (of undercoating) it’ll definitely extend the life of your car,” Kuhn said.