by Jasper Kallsen
Starting in 1938, the discovery that using salt was a cheap and effective solution for removing snow and ice from U.S. roads caused its use to spread nationwide. After just five years, around 5 million tons of salt were used on roads across the United States. Currently, it is estimated that 20 million tons of salt are used for U.S. roads every year. While this may not seem to matter here in perpetually sunny San Diego, the extensive use of salt can cause significant issues.
The salt used for roadways is rock salt, also commonly known as road salt, and is very similar to the common table salt. Some key differences include rock salt typically having larger granules, the substance that makes salt coarse, and that rock salt is mined from vast underground deposits which were formed in the aftermath of prehistoric ocean evaporation. Using the road (rock) salt is an effective way to remove snow and ice from roads, but its use negatively influences not only the environment, but also human health. The salt has been proven to cause contamination of drinking water, the endangerment of wildlife, an increase in soil erosion, the damage to property, as well as countless other harmful consequences.
In the past 50 years alone, 37% of drainage areas have increased in their salinity. Underground water has been affected, particularly water stored in wells. Well water in close proximity to roads and other pavement that use road salt is more likely to exceed EPA health standards. Furthermore, road salt modifies not only well water, but in addition can consequently contaminate nearby drinking water reservoirs, which can be seen best through the Flint Water crisis, which severely affected the drinking water of Flint, Michigan for five years. Scientists believe that the high levels of road salt that promoted extreme amounts of chloride was not unique to just the Flint water supply, but also to that of others around the nation.
High sodium levels resulting from road salt creates toxicity for fish, bugs, roadside plants, and wildlife. Salty roads commonly attract animals such as deer and moose as they enjoy licking the minerals found in salt. and as a result the roads increase the probability of roadkill and accidents. In addition to wildlife, the road salt affects runoff water by causing oxygen depletion in bodies of water by the salt naturally sinking to the bottom of the water floor, which creates a dense layer of salt. As previously noted, road salt not only alters the environment, but humans as well. This can be seen by the high levels of salt being highly corrosive to roads, bridges, cars, and other forms of infrastructure. An estimated $5 billion alone is spent yearly in the U.S. to combat salt corrosion. The expensive costs and the massive impact of environmental and human consequence proves that road salt stands to be quite a desecrating force.
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