Salt Seen as Building Threat

As conservationists and the public became more aware over the past decades of the dangers that nutrients and sediment posed to lakes and bays, another common element was silently polluting Adirondack waters with scarcely any notice: 


Subsequent research has largely quantified the extent of this pollution, and the potential it has to do serious damage if something isn’t done. 

It has also identified the source of the problem, that being the road salt spread over state roads to combat ice and snow.

The situation suggests an obvious conflict, between people who insist that state waters be uncontaminated, and drivers who insist roads be safe to travel in winter.

At the Fourth Annual Salt Summit in Lake George last week, keynote speaker Laura Fey of Montana State University said that community understanding and cultural change is key to resolving this conflict.

Do you need to go out on a snow day? Do you need to run to the store for butter and milk when it’s storming out? Do we need go 65 miles an hour in a snowstorm?” she said. If educated, the public is capable of understanding and accepting two cleared “wheel paths” on a snowy road, instead of expecting the entire road surface to be cleared — which take significantly more salt.

Salt can also be wetted prior to spreading, which helps it stay on the road. 

And where 95 percent of the salt spread by a plow traveling 25 miles an hour stays on the road, trucks traveling 45 miles an hour scatter salt that bounces off the highway entirely. 

You’re throwing away 25 percent of your salt budget,” Fey said.

Properly calibrating salt trucks can play large dividends, both the lake health and to taxpayers. Drivers in improperly calibrated trucks might be spreading several times more salt than they need to.

Other speakers detailed the considerable footprint that salt has already left in the park. 

Dan Kelting, of the Adirondack Watershed Institute, said studies have shown elevated levels of sodium and chloride in streams, lakes and wells that are downhill of state roads (state roads are more heavily salted than local roads, which more often use sand as an abrasive). 

In real terms, this translates to 52 percent of Adirondack streams and 77 percent of lakes that show concerning levels of salt. 

Private wells are suffering too.

Of 114 private wells studied downhill of state roads, sodium levels were nine times higher than in 132 wells that were not near a state road.

Kelting said salt in the water can cause problems for people with hypertension, and also is bad for appliances such as water heaters, washing machines and dishwashers. 

This all goes back to how the roads are treated,” he said.

On the environmental front, Rick Relyea, a member of the scientific coalition known as the Jefferson Project at Lake George, said salt can kill zooplankton that are one of the foundations of the aquatic food chain, ultimately affecting the fish population. And without these creatures to feed on microscopic plants, water can turn an unappealing green.

There are also bizarre twists in the story. 

Saltier waters seem to cause a sex change in wood-frog tadpoles, skewing the population toward the male of the species. Salt also interferes with the inner clock of zooplankton that tells them to rise to the surface and feed at night and then descend to the bottom during the day for protection. 

The molecular clock in their brain is flatlined,” Relyea said. 

Nor are salt substitutes necessarily the answer for winter highway treatment. 

Magnesium and calcium chlorides in some instances do as much damage as traditional road salt, and even organic additives such as beet juice “compost” when they run off into the water, causing the same problems as other nutrients that feed algae blooms.

Relyea warned that there will come a point in lake ecology where the effects of salt are irreversible. 

The good news is that this point of no return is still some way off, giving conservationists and highway departments time to plot alternative courses. He also praised The FUND for Lake George, the sponsors of the annual summit, for the progress it has already made and the attention it has brought to the issue. 

You’re really going to be the example for lake communities around the world,” he said.

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