State highway crews in the area now have a new way to make winter roads safer while also saving money and helping the environment. It’s called an ice-breaker.
After a heavy snowfall, snow that doesn’t get immediately removed tends to get packed down and turns into a thick layer of bumpy ice that is difficult to remove from roadways.
According to Scott Johnson, group leader and snowplow driver at the Minnesota Department of Transportation truck station in Alexandria, the old method of removing compacted ice involved repeated applications of salt or using a slow-moving road grader to try to break it loose.
The new way is to use the ice-breaker – a two-ton roller with spikes that is mounted to the front of a snow plow truck.
“It’s an invaluable tool when we need it,” Johnson said. “It takes the ice mat on the highway and breaks it up into little pieces.”
He explained that the ice-breaker is typically rolled over the ice on a road at about 15 to 20 mph, followed by an application of salt brine. The salt then gets to the road surface fairly quickly through the breaks in the ice. After a couple hours, the ice is generally loose enough to be scraped off with a snow plow, he said.
In contrast, the old method required repeated salt applications because the salt melted the ice slowly from the top down.
“I’d say we use a quarter of the salt,” Johnson said. This cuts down on labor and material costs as well as helping the environment.
However, he stressed that safety is the No. 1 concern when removing ice.
“By doing that quicker, we can make the roads safer, faster,” he said. “That’s the key.”
Originally developed for use at airports, the ice-breaker was added to the Alexandria truck station last year. It is part of MnDOT District 4, and there are now four of the ice-breakers spread throughout the district.
“We’re going to purchase one or two more, because they are a great tool,” Johnson added.
He also emphasized that because the roller is just heavy enough to break up the ice, it won’t damage road surfaces.
MnDOT is responsible for clearing state highways, such as Highways 27 and 29, as well as Interstate 94.
Ice and snow removal innovations
The Minnesota Department of Transportation also has a couple of other innovations that are in use in the Alexandria area.
The first is the tow plow, which is a snow plow on a trailer that is pulled behind a plow truck. With a 20-foot blade, the tow plow can be used in combination with a front-mounted plow to clean a wide path of road with one pass.
The second, and more significant, is the use of salt brine, which saves on salt usage and makes salt application effective to a lower temperature.
Johnson explained that where rock salt is not as effective as temperatures get colder, brine (salt mixed with water) works well down to 15 degrees. Typically, it is applied directly after rock salt, which helps to activate it and make it most effective, he said.
Although they Alexandria department has used brine for several years, it is using a lot more now and has a new brine-making system that can make several thousand gallons of brine each hour, he said. Salt brine is then stored in large tanks where it can be loaded into trucks as it is needed for application.
As with the ice-breaker, the use of brine results in savings of both material and time, as well as helping the environment by using less salt.
“The environmental benefit of salt brine is astronomical, especially in this area,” he added.