Inside Science News Service reports that two factors are encouraging state transportation departments to find more efficient ways to de-ice roads. The first is cost. While salt doesn’t cost much, having to re-apply it frequently does cost a lot. The second factor is salt seeping into groundwater and streams. Tests in 2010 showed an increased level of chloride in 13 streams near cities in northern states (regular salt is composed of sodium and chloride).
Adding a carbohydrate to the salt, such as leftover whey from making cheese, or beet juice from farms – can make salt stick to the road longer. The beefed-up salt lasts between five to 10 days instead of just one day for plain salt.
