COLUMBIA - The Missouri Department of Conservation is warning mid-Missourians about the dangers to plant life when using salt and salt compounds to de-ice roads.
Angela Belden, resource forester for the department, said even though this winter has been mild and not much salt has been placed on roadways, salt buildup over the years can still cause issues.
"It affects the soil in that it kind of clogs those empty spaces between the soil particles so that water can't infiltrate, and it just kind of makes sort of a crust so water can't get down into the roots," Belden said.
However, there are alternatives to salt and other salt compounds, and though they may be more expensive, Belden said many areas still use them.
"I think it is an environmental issue," said Belden. "A lot of places use sand, also, or they'll use a combination of something with grit and the salt, so they're not throwing out as much salt."
Steve Sapp of Columbia Public Works said in the past few years, Columbia has switched from using fly ash and salt to salt compounds, brine, gravel, and even beet juice as more environmentally-friendly alternatives.
At the city's Walter Leroy Anderson Salt Facility, a storage area two stories tall is full of ash to use in special circumstances. Sapp said the ash is still used for when traction is needed on an icy road--not to actually get rid of the ice. He said the city eliminated ash as a mainstream option for both cleanliness and environmental reasons, since the ash runoff into streams can cause issues for water and wildlife.
In addition, a dome-like structure houses salt, and other machines dispense brine and calcium chloride, other compounds used to treat icy roads.
Sapp said that the city monitors conditions closely in order to determine which method to use.
"We subscribe to a private weather forecaster that really watches just the Columbia, Boone County area really closely for us and talks to us about precipitation. We monitor road temperatures...and then we look at what kind of precipitation precedes the frozen precipitation," Sapp said. "We've had a lot of rain over the past couple days, so pre-treating with the calcium chloride or with a salt brine solution, or with the beet juice would've simply washed away, so it wouldn't have done any good."
Sapp said the ice doesn't just affect roads and highways--it can affect runways, too. The Columbia Regional Airport may have had to shut down a couple times this year had it not been for some salt alternatives used to clear the runway.
"We're using a new chemical on the runways now for de-icing and pre-treatment agent that will take the melting temperature down to about five degrees above zero," Sapp said. "We're using a very stiff broom that brooms the snow and ice off the runway. It doesn't compact it and make it slick," said Sapp.
All in all, Sapp said there is no perfect fix to de-icing roads.
"There's no real magic solution to all this. It's just how do we treat our roads to make sure that they're safe and passable," said Sapp.