Q: Why doesn’t the city of Madison use alternatives to salt to melt icy roads?
A: There are ways other than salt to melt snow and ice on pavement, but Madison Streets Division spokesman Bryan Johnson said those alternatives aren’t viable.
“We have tried beet juice in the past to further limit our salt use, but we do not use it currently,” Johnson said. “We were directed by the Public Health Department to stop using it because beet juice has what’s called a high oxygenation rate, so when it decomposes in the water, it sucks the oxygen out and could result in fish kills in the lakes.”
The Streets Division does look for other options for snow and ice control, Johnson said, but other chemicals like magnesium chloride and calcium chloride are more damaging and more expensive than salt.
Airports have their own winter-weather treatments that are chloride-free per Federal Aviation Administration regulations, but Johnson said those options were out of the question as well.
“(Those treatments are) so very, very expensive. A municipality could never possibly consider using them,” Johnson said. “There just really isn’t a consequence-free material or substance we could put down on the roads to keep them open and safe for travel.”
The Streets Division currently uses salt and salt brine to ease the effects of winter weather on Madison streets.
The salt brine — which is a saltwater solution of 23.3 percent salt — is applied to major streets before a snowstorm if temperatures are high enough to make it effective. When it is applied before the snow hits, Johnson said it keeps the snow from bonding with the pavement, making it easier to scrape off when the plows come through.
The salt brine is also used in conjunction with regular salt. The brine is sprayed on the roads to keep the salt on the driving lanes instead of blowing onto the shoulder or ground.
Johnson said Madison’s use of salt on roads doesn’t mean the Street Division isn’t taking the environment into account.
“We feel that (by) pre-treating the roads when we can, and just generally being very cautious about our salt application, we are minimizing the impact of salt on the environment,” Johnson said.
When salt is used during winter weather, Johnson said it is spread at a rate of 300 pounds per mile for two lanes and only on main thoroughfares, major connector streets and around schools and hospitals along with major hills and curves.
All other streets are sanded to provide more traction for vehicles.