Why Road Salt

04 Aug Why Road Salt

Every winter, 22 million tons of road salt, approximately 137 pounds per person, are used by U.S. officials to melt the ice on the roads during cold weather.  By depressing the freezing point of the water, salt melts the ice left on roads during snowstorms, making roads safer to drive.  Applying salt to the roads has now become a standard for fighting snow due to its low-cost and effectiveness.

What is Road Salt?

Road salt, or rock salt as it’s sometimes referred to, has the same molecular make-up as the salt used in food: sodium chloride.  While table salt is purified, ground and combined with additives to prevent it from clumping, road salt is coarser in texture and larger in size.  It is primarily made from mining it underground, where it formed due to evaporation from ancient seawater years ago.  Underground shafts are followed by miners, who break out large slabs with specialized machinery and dynamite.  It is then crushed by hauling the slabs in trucks to crushing machines.

Salt mines exist all over the world; however, in the United States salt is primarily mined from under Detroit, New York, Cleveland, Kansas and Louisiana.  It was discovered in Detroit in 1895, where donkeys were used to haul the slabs out of the mines.  It was in the same city in the 1940s that salt was first applied to roads to melt the ice. Pure water has a higher freezing temperature than water that is salted.  When salt is applied, the freezing temperature is lowered as much as 25 percent, and the ice on the roads melts.

How is Road Salt Applied?

Road salt was first applied to roads by the shovelful from the backs of trucks. The 1950s brought rollers, which extended the entire width of the truck, spreading the salt in a wide path.  It was later applied in more narrow lines that produced a concentrated brine, which easily flowed down the pavement to break the bond between the ice and the road. It can also be applied as a salt water solution from hoses.  Salt that is pre-wetted with water, which adheres well to the road, cuts down on melting time.

Today most salt is applied to roads with a truck applied with a chute, which the salt runs down, or a spreader that uses a spinning disk to spread the salt in a semi-circle.  Road salt is most often used in correlation with snow plows that push the ice and snow away after the salt breaks the bond with the asphalt.

Is Road Salt Effective?

A 1976 study found that using ice on roads reduced wages lost due to lateness from snow on roads by $7.6 billion.  The same study found that it saved $3 billion due to absenteeism from poor road conditions and saved 1.4 to 1.5 billion liters of fuel. The trend continues today.  A study done by Marquette University in Wisconsin discovered that the use of road salt reduced automobile accidents by 88 percent, injuries by 85 percent and the cost of accidents by 85 percent.

Many cite concerns over the use of road salt because salt can corrode roads and structures, and it has an impact on the environment of the area.  Recent changes to road salt application, including pre-salting roads before the snow begins to fall, have been able to reduce the amount of salt used and its impact on the environment.  Most experts also say that using road salt is much safer for the environment and humans than the use of chemical de-icing alternatives.

Why Road Salt?

Road salt is low-cost transportation safety solution.  It has been long proven as a successful de-icer that saves money to businesses, gas money to consumers, prevents accidents and saves an untold number of lives each winter.

Same Day Aggregates has delivered thousand of tons of road salt to regional users.  We can help meet your road salt demand as well.  Contact SDA today for fast quotes and delivery options.