Anti-Icing Guide: Salt Application vs. Brine Application
Snow and Ice bring joy to many during the winter months. There are many great activities that thrive when we are blessed with large amounts of snow. The one thing that nobody likes to do is commute to work in the snow. For this reason, our counties and states work very hard to quickly remove the snow and ice from our roads so that people can stay safe on our many miles of roads. Over the last decade, there have been many advances in technology that have helped our DOT’s battle these elements. This article will cover dive into salt and salt brine applications.
Traditionally, rock salt has been the chemical of choice for helping melt snow and ice off roadways. During winters with many snow events, this can be a pricey undertaking for our state governments. When salt is applied, we want to make sure it stays on the roads to help melt and not get pushed off into our ditches and waterways.
Environmental Impact of Road Salt
Road salt can damage vegetation near roadways. Trees growing close to roads will begin to turn brown and branch dieback will set in. Road salt can also impair roadside soils by displacing other minerals and absorbing excess water. This condition is called physiological drought. Physiological drought won’t allow plants to absorb the necessary water they need to live even though the water may be available to them.
Road salt is also damaging our waterways. The salt eventually makes its way into the ground water increasing the amount of salt present in fresh drinking water. The chloride part of salt is also toxic to aquatic life. High chloride levels inhibit aquatic species’ growth and reproduction, impacts food sources, and disrupts osmoregulation, the process of regulating water entering and leaving the skin, in amphibians. Road salt runoff can also deplete the amount of oxygen stored in a body of water.
How does salt work to melt snow and ice?
Salt melts ice through a process called freezing point depression. Instead of water freezing at 32⁰ F, the freezing point lowers to -5⁰ F depending on the salt concentration. Salt also needs moisture to begin the process of lowering the freezing point. Most highway plow trucks now use prewetting systems that spray water on the salt before it gets broadcast onto the roads. This allows for the salt to be preactivated and ready to begin the melting process when it hits the road. It also helps with the salt to stay on the roads and not get broadcast into the ditches and waterways as runoff. State DOT’s have found that they use about 30% less salt per lane mile with this method of application.
Transition to Salt Brine Technology
Over the last 5 years, many DOTs have started to use a more proactive approach to salt application. This approach uses a salt brine solution that gets applied before a snow event. The salt brine is made to a 23% solution that prevents ice from forming on roads during a snow event. Because the snow and ice don’t adhere to the roads, the plow can scrape them down to bare pavement. Government agencies can produce the Brine Solution quickly with systems like VariTech’s Brine Boss. The salt stays in solution for ever and can be stored in tanks waiting for the next snow event. Since this method has been so successful, government agencies have been able to drastically reduce the amount of salt that is applied per lane mile.
If you’d like to talk to someone about converting your equipment to be able to handle salt brine or pre-wetting your salt, contact the knowledgeable people at VariTech Industries at 1-888-208-0686.