Tuesday, February 18, 2014

A Low Salt Diet for the Bay?

Crews have been treating roads with more than the usual amount of salt during this extra snowy winter. Many people are concerned over the effect it is having on their cars but researchers are more concerned by the impact of it in our water.

The salt that is used to treat snowy roads remain on the surface so when it rains or when the snow melts, it runs into storm drains and ultimately into Maryland waterways. Environmentalists are always measuring contaminants in the Chesapeake Bay. A couple of years ago, researchers with the University of Maryland found elevated levels of chloride after a particularly rough winter, which is the main ingredient of road salt.

Dr. Beth McGee notes, "Chloride is toxic to aquatic organisms and so they're worried that the levels they're seeing could impact local streams."

So far this season, the State Highway Administration (SHA) has dumped about 400-thousand tons of salt on Maryland roads. They only use what is necessary but this unusually icy winter has required much more.
400,000 tons! Wow, sounds like a lot, right?  Well it is when you buy it by the ton.  But let's put that into some perspective.

The volume of Chesapeake Bay is some 18,000,000,000,000 gallons, or more than 64 trillion liters. and the Bay is approximately half ocean water, which contains 35 grams of salt per liter.  Thus the Bay usually contains a little less than 2 trillion grams, 2 billion kilograms, or 2 million metric tonnes of salt (a metric tonne is about 2,200 lbs).  So, in a worst case scenario, where all the road salt runs into the bay at once,  road salting has contributed about 20% of the Bay's salt, at a time of year when the salt content of the Bay is at it's lowest.
"We value the Chesapeake Bay. We want to reduce as much salt as we can, but the reality is we need to keep the roads from icing up," said Valerie Burnette Edgar of the SHA. Scientists agree that public safety is important but also hope to find more ways to reduce runoff. They are even researching alternative ingredients but they can be as much as ten-times more expensive.

The SHA "has experimented throughout the years and piloted use of different products and we're always open to trying different products. The reality is the tried and true salt is the best way to keep the roads safe," said Edgar. Salt water sea life such as crabs in the Bay can generally adjust to chloride but the freshwater streams are most endangered by it.
Not only do most of the Bay's organisms "adjust to chloride," all of them require it (it is an essential mineral).  And many of the the Bay's creatures are limited by low salt conditions.  Low salt concentration limit the range of oysters clams, and many marine and estuarine fish in the Bay.  

Road salt is somewhat more of a threat to freshwater streams; freshwater organisms, while requiring salt, usually have some upper limit of toleration that road salt may approach, but I have yet to see any data showing such an occurrence has happened, let alone is a wide spread problem

It pisses me off when the professional grievance mongers invoke the sacred status of Chesapeake Bay in such a misleading way to attempt to block something which is so important for the public interest.  If you don't think so, try driving on some of our roads after a snow, and before the salt trucks come.

Remember, it's not so much that they love the Bay, it's that they hate people.

1 comment:

  1. They can always go back to the old fashioned way of dealing with snow ... in New England the roads were "rolled". In other words, the snow wasn't removed, it was packed down into a hard surface, that became icy, and the sleighs and horses were able to move on that.

    Something tells me that modern society isn't that willing to go back in time - they like their automobiles and modern truck delivery commerce system too much.

    Or where I grew up, they "cindered" the roads, with the clinkers from coke ovens ... the stuff was called "red dog". They abandoned that once they found out it had high benzene concentrations in it. ANd everyone used tire chains, as well. The hills were steep.

    The choice is apparently between salting roads, or increased traffic deaths.