It is that time of the year where you never know what the weather will bring, e.g. snow, ice, or sleet. Maryland’s best response to this dangerous weather is the use of salt, but how is it affecting the Chesapeake Bay?
According to the Department of Natural Resources (DNR), about 10-20 million tons of salt is used each year in the U.S. in order to make our roads drivable during severe weather, with majority being applied to roads within the Mid-Atlantic region. During an average winter a four-lane highway, located within the Chesapeake Bay region, will receive about 20 tons of road salt per mile. DNR puts it in perspective saying that this “would be equivalent to over 15 billion gallons of seawater” if all the salts were dissolved in water.
Ocean water has high salinity; so, if this is a natural compound that is already found in water, how bad can it be? Well, the salt we use to treat our roads does not contain just sodium chloride; it contains impurities as well, such as phosphorus, nitrogen, copper, and cyanide. Cyanide can break down under certain conditions making it very harmful to humans and wildlife. Scientists have found a range of 3 to 270 parts per billion (ppb) of cyanide in urban streams for a short amount of time after salt has been applied. At 20 ppb cyanide begins to be toxic to aquatic life. Furthermore, Sodium chloride may not be toxic to humans and seems to have little effect on our drinking water; however, Canada has recently declared road salt as an environmental toxin, where about 1,000 ppm can be harmful to aquatic life. Streams and wetlands have been found to be well over this amount during the winter months and the species within these ecosystems are not adapted to live in saline waters.
A recent article published in the Baltimore Sun, “Road salt is killing Garrett County”, claims that Maryland State Highway Administration (SHA) is “destroying Mountain Maryland” because of the 48,352 tons (more than 80 tons per lane-mile) of salt that was applied during winter 2012. Although it is of priority to keep our roads safe it was found that the Upper Peninsula of Michigan receives 50 percent more snow than Garrett County, yet only “used 24 tons of salt per lane-mile”.
SHA officials were found to have no clue as to how much salt is being used in Maryland compared to other states and there is apparently no official method to salt usage.
During the winter months be conscious of the amount of salt you use around your home and where the storm drains run. Furthermore, look for products that are more environmentally safe and safe for your pets as well. Yes, we should do what we can to make traveling safe, but we must make sure it makes sense and we are not destroying an ecosystem in the process and spending tax money recklessly.