Why is salting roads bad for the environment

Have we got enough of the stuff to see us through winter? When are the emergency orders placed abroad due to arrive? Why hasn't my road been salted yet? But when the big thaw comes, expect this new-found interest to melt faster than the snow itself. One important question does remain, though: where do the thousands of tonnes of rock salt dumped on our roads during every cold snap actually go once they are washed away?

Sodium chloride sand and anti-caking agents are often added to the grit, too can have a deleterious impact when it comes into contact with plants and animals in high concentration — just ask any slug. An increase in water hardness has shown evidence of decreasing the toxicity of heavy metals Lewis, In order to reduce the corrosive effects of some of the chloride-based deicers, corrosion inhibitors can be added.

Corrosion inhibitors can include heavy metals, inorganic ions, and organic substances Levelton Consultants Ltd. The toxicity and environmental effects of corrosion inhibitors vary greatly and are dependent on the composition Pilgrim, In general, the inhibitors that contain organic components consume oxygen during decay. The oxygen consumption can lead to anoxic conditions in the soil, groundwater, or surface water Fischel, At colder temperatures, the rate of decomposition will decrease and there will be an increased potential for the inhibitors to reach the groundwater Cheng and Guthrie, Much of the information on the environmental impacts of acetate-based deicers is based on studies regarding calcium-magnesium acetate CMA Therefore, much of the information presented in this section is related specifically to CMA.

Despite high mass loading, runoff and receiving water are predicted to dilute the concentration. The characteristics of acetate suggest it would be absorbed to the soil surface and not carried away with the runoff. Once in infiltrating water, acetate can be mobile, however Horner found that less than 10 percent of the acetate applied to test plots were found in the underlying soil and groundwater.

The sodium and potassium contained in other types of acetates are less likely to adsorb to the soils and therefore have a greater potential to leach into groundwater Cheng and Guthrie, Horner did not note any effects of acetate on soil plasticity, moisture-density characteristics, unconfined compression strength, or shear strengths in medium texture soils.

An increase in permeability was noted. In the Horner study, the test sites that received an addition of CMA were found to have an increase in permeability up to 20 times more than that of the control plots. There is uncertainty about CMA causing the release of metals from soil Amrhein et al. Another concern is that acetate-based deicers consume oxygen when degrading.

Acetate-based deicers dissociate when in water. The metal ion persists, but the acetate ion will degrade Fortin et al, Degradation of the acetate ion consumes oxygen, which is one of the biggest environmental concerns associated with the use of acetate-based deicers. Modeling studies have predicted CMA concentrations in the highway runoff range from 10 to ppm, with a maximum concentration of 5, ppm. Dispersion and dilution are likely to mitigate the negative effects of CMA, and the environments most likely to be severely affected are slow moving streams and small ponds Fischel, Carbohydrate-based deicers are often made from the fermentation of grains or the processing of sugars such as cane or beet sugar Rubin et al.

Small quantities of carbohydrates are sometimes used with other deicers. Alone carbohydrates do not aid in melting ice or snow; however, their use can help reduce the freezing point of ice further than salt and can help salt stick better to the road surface Fortin et al, ; Rhodan and Sanburn, Carbohydrates are not corrosive to steel, and at high concentrations, carbohydrates can act as a corrosion inhibitor for salt brines. There is evidence that the use of carbohydrates in the United States is increasing.

For example, sales of a beet based product called Beet Heet were around , gallons at the end of the winter season in By February of , 1. The Morton Arboretum in Lisle, Il uses beet juice in their deicers. The beet juice additive has minimal environmental affects, and helps the salt stick where applied. Another unconventional additive that has been used is cheese brine. Wisconsin has used a cheese brine in at least six counties in the state Rhodan and Sanburn, Fu et al. When used as a prewetting material, there was no statistically significant difference between any of the chemicals.

The decay of the alternative additives in the environment will contribute to BOD most specifically for the organic additives. It is more accurate to state: It is believed that deposits were formed after prehistoric oceans evaporated.

So what your telling me is. That something as simple as salt on roads is hurting the environment. So salt is hurting the environment? Ecology , Sustainability , Water. An underground salt mine. Photo: Cargill. Tags: ecology Environment freshwater Groundwater health New York New York City new york watershed roads salt Sustainability water conservation water matters water pollution.

Notify of. I agree to help cultivate an open and respectful discussion. Oldest Newest Most Voted. Inline Feedbacks. Mindy Kost. So due to the salt runoff into my front yard, no plants will grow there?

Jeremy Hinsdale. Reply to Mindy Kost 2 years ago. Rick Merrill. How are private wells affected by brine and salt in Massachusetts? Reply to Rick Merrill 1 year ago. Reply to JoJo 1 year ago. Reply to Melissa 1 year ago. Reply to Ben 21 days ago. Reply to Ben 1 year ago. Robert Kosin. Reply to Aneesa 9 months ago. Jo Ann Sorensen. I am trying to get a better understanding of these events and how they can be mitigated.

Can you direct me to additional sources of information? Nick Gurr. Last edited 2 months ago by Nick Gurr. Would love your thoughts, please comment. This website uses cookies as well as similar tools and technologies to understand visitors' experiences.

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