When big snow and ice blow in, most people reach for salt. There are ways to reduce its harms

Winter has its fans, but even those who enjoy playing in the snow probably dislike the chore of clearing up after a big storm that dumps several inches or even feet of snow and ice.

It's easy to dash to the closest hardware store to grab a bag of salt, but experts say there are a lot of environmental and other factors to consider when tackling all that ice and snow.

Here's what to know.

What kinds of salt are out there?

Rock salt, also known as sodium chloride, is the cheapest and most commonly used product. But it's not great for the environment and it's not the most effective option out there.

"There's a chart we reference that’s chemical effectiveness at certain temperatures. And really, when you get to about 15 degrees or colder, you can keep applying more and more rock salt and it’s not going to do any more than it already does,” said Martin Tirado, CEO of the Snow and Ice Management Association, a trade group for industry professionals.

In those conditions, other products — calcium chloride, magnesium chloride — release heat that helps the salt work better, Tirado said.

The different formulations vary in other ways, too, including how quickly they work, their corrosiveness and how they interact with moisture. Calcium chloride and magnesium chloride can cost at least twice as much as rock salt.

But all contain chlorides that can pollute fresh water, damage shrubs, trees and grass and crumble concrete sidewalks, stoops and driveways.

Blends and coatings can reduce the corrosive nature and environmental hazards of these salts, experts say.

Calcium manganese acetate is one of the tamest de-icing products out there, developed specifically to replace rock salt and be more environmentally friendly. It is biodegradable, a corrosion inhibitor, and typically used as a liquid. But it is much more expensive and can still create issues with dissolved oxygen on bodies of water.

What about those environmental effects?

Pamela Bennett, a horticulture professor at Ohio State, said rock salt is the worst for plants. It gets them in two ways: through the roots and through the air.

Salt percolates through the soil. When plants start to draw in salty water in the spring, that dries roots, leading to dry leaves. Brown tips on leaves indicate the soil might have gotten too salty.

Salt can also reach plant foliage — in the winter, that's evergreens — directly when it's carried by mist and spray. That's an issue that's worse on major roads as a lot of traffic moves quickly.

“When you have a lot of road salt on the highways, cars are splashing and wind blows it. That salt turns into what looks like a burn,” Bennett says.

What about my pets?

Most people walking their dog in snowy places have seen what happens when they walk across a heavy salt treatment — stopping suddenly and lifting a paw as if in pain.

“Their paw pads get dry or they get little cuts because those crystals are sharp, and then they’re chewing them because that’s the only way they know to make it feel better,” said Alison Manchester, an assistant clinical sciences professor at Cornell University. If they swallow enough salt, it can lead to vomiting, too.

For some people, animal safety is a strong reason to look to a nonsalt option against ice and snow.

So what are my nonsalt alternatives?

Abrasives such as gravel and sand can help with grip, so pedestrians and tires are less likely to slip. But they also come with their own problems.

Sand that runs off into freshwater bodies — lakes, streams and rivers — can kill natural growth, Tirado said.

Sand can also accumulate in your soil, eventually becoming a problem for plant growth. It can even make a type of concrete when it mixes in clay-heavy soils, experts say.

Unconventional solutions are out there. You can buy a de-icer that wraps its chlorides in beet juice or beet extract that coats the granules for a variety of benefits, including melting ice faster, working in colder temperatures and staying where it's put. And a Korean company, Star's Tech, is working with material taken from invasive starfish to produce a de-icer that it says more slowly releases chloride material and thus avoids some of the corrosion and environmental problems of salt.

Be ready to shovel more than once — and don't over-apply

Experts say preparation and strategy can make clearing ice easier. That starts with watching forecasts to see how much snow is expected.

“People wait until after the storm to start shoveling," Tirado said. "That’s fine if you’re having 1 to 2 inches. If you start getting 3, 4 or more inches than that, you can’t wait ... you need to go out multiple times. That way it keeps the paved surface more clear in a productive and proactive manner.”

Ground temperature matters. If it’s warmer, you may be able to use less than you think you need. Colder ground temperatures might require more.

Proper application of whatever you put on your sidewalk or driveway is important, too.

“The key here is to not use too much and scatter it too much," said David Orr, director of the Local Roads Program at Cornell. “We also do probably need to get into the habit that it may not be perfectly bare and that can be OK."

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