Tag: road salt

Road Salt Damage (2008)

Each year about 118,000 people are hurt and 1,300 people are killed on the roads during snowy and icy conditions. So, snowplows hit the roads, scraping snow and ice off the surface… and spreading incredible amounts of salt on highways, streets and roads to help keep them clear. Lester Graham reports there’s some concern about the long- term effects of all that salt:

Transcript

Each year about 118,000 people are hurt and 1,300 people are killed on the roads during snowy and icy conditions. So, snowplows hit the roads, scraping snow and ice off the surface… and spreading incredible amounts of salt on highways, streets and roads to help keep them clear. Lester Graham reports there’s some concern about the long- term effects of all that salt:


This dump truck is getting ready for a load of salt for a coming winter storm. Salt helps make icy roads safer. It helps prevent people from slipping and falling on sidewalks. And… it’s pretty cheap. But there are problems with salt. Salt pollutes and salt corrodes.


Mark Cornwell has spent a good deal of his career trying to convince highway crews that there are better ways to keep things safe and reduce how much salt is dumped on roads and sidewalks:


“Salt basically damages just about everything it comes in contact with. Salt moves through concrete and attacks structural steel, bridges, roads, parking structures; it eats the mortar out of bricks and foundations. It damages limestone, you know, just on and on and on.”


So, even though salt is cheap, the damage it does costs a lot. It’s a hidden cost that’s seldom calculated. Imagine the cost of having to replace a bridge five years early because the structure is weakened by salt. And then there are your direct costs: trying to keep salt washed off your vehicle, and still seeing rust attack your car.


Cornwell says there are some cities and road commissioners working to reduce the amount of salt spread on the roads. But in most places, the political pressure to get the salt trucks out early, and laying it on thick to keep drivers happy, outweighs any concerns about trying to reduce the salt:


“I’m sure the public expects full attention to snow and ice. And they have absolutely no understanding, however, of what it costs to provide that.”


Nobody thought a lot about the damage salt was causing until the last couple of decades. In a few places, the people responsible for keeping the roads and walkways safe have been trying to reduce the amount of salt they use and still keep public safety tops on the list of concerns:


“So, this is our shops. The brine-maker is right here.”


Marvin Petway is showing me some of the tools in his arsenal to reduce how much salt is used and still keep things safe. He works at the University of Michigan, where there’s a goal to cut the amount of salt used in winter in half. What they’ve learned is using innovative ways of putting down salt can actually help melt snow and ice faster. One way is to mix it with water to get the chemicals in salt working a little more quickly:


“Why use 5 pounds of rock salt when you can use 2 gallons of liquid salt? We’re able to get better coverage, quicker, better cost, and we’re putting the material that is effective in reducing ice build-up directly to the area where we don’t want ice located.”


The crews trying to reduce salt use computer assisted spreaders to measure out only the salt needed, they mix in less corrosive chemicals that make salt brine more effective, and even just wetting the salt in dump trucks with chemicals all help to melt snow and ice faster and in the end use a lot less salt.


Nothing is going to replace salt altogether, but those efforts can add up to a lot less salt. That means less destruction of infrastructure.


But there are more reasons for reducing salt than the damage to roadways and parking decks. Salt also damages the environment.


Mark Cornwell first noticed the effects of salt because he was a horticulturalist. He’d work all spring, summer and fall planting shrubs, make the grass green, tending beds of flowers. Then the winter would come:


“Unfortunately what we were doing in six months of winter was undoing everything we did in the other six months of the year. If you’re going to get ahead, you’ve got to solve the problem and in my mind, that was misuse of salt.”


Use too much salt and it kills plants. And it turns out the cost of using all that cheap salt could be even greater than anyone guessed. For decades, it’s been assumed that rain washed away most of the salt, but studies in Ontario find that a lot of the salt doesn’t get washed away.


Instead, a good deal of it is percolating down into shallow aquifers. Researchers predict that in the future we’ll start find salt is getting into the groundwater that supplies many of the wells where we get our drinking water.


For the Environment Report, this is Lester Graham.

New Road Surface Could Mean Fewer Salt Trucks

  • A new coating on a road surfaces could lower its freezing point, preventing ice formation. (Photo by Cristian Pricop)

Drivers are testing out a new road coating that could reduce accidents in the winter. And as the Great Lakes Radio Consortium’s Stephanie Hemphill reports, it might also mean fewer trips for highway salt trucks:

Transcript

Drivers are testing out a new road coating that could reduce accidents in the winter. And as the Great Lakes Radio Consortium’s Stephanie Hemphill reports it might also mean fewer trips for highway salt trucks:


Russ Alger directs the Institute of Snow Research at Michigan Technological University. He’s come up with an aggregate that can absorb road salt. The aggregate is glued to the road surface with a tough epoxy. Alger says the aggregate can hold onto road salt for an entire season. That means when it gets cold, the salt will prevent ice from forming.


“And so in essence what we’ve done is we’ve lowered the freezing point of the pavement itself, and what that means is, twenty degrees pavement temperature now, ice won’t form at the surface of it.”


It also means road crews can use less salt, and make fewer trips to trouble spots. The new coating was installed on a bridge in Northern Wisconsin. Alger says accidents there have been reduced dramatically. It’s also being tried out on some runways at Chicago’s O’Hare airport.


For the GLRC, I’m Stephanie Hemphill.

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A Road Salt Substitute?

  • Road salt spread on the streets of Ann Arbor, MI has a corrosive effect on this sewer grate. Many cities and states are looking for a less damaging, and more environmentally sensitive alternative to road salt.

With winter officially arriving, many towns and cities in the Midwest are preparing to fight the snow and ice that can make roads slippery and dangerous. That traditionally means spreading salt, but salt is damaging to the environment, so there is a growing movement toward using less corrosive and polluting means to make streets safe. The Great Lakes Radio Consortium’s Jonathan Ahl reports:

Transcript

With winter officially arriving, many towns and cities in the Great Lakes Region are preparing to fight the snow and ice that can make roads slippery and dangerous. That traditionally means spreading salt. But salt is damaging to the environment. So there is a growing movement toward using less corrosive and polluting means to make streets safe. The Great Lakes Radio Consortium’s Jonathan Ahl reports:


Rock salt and calcium chloride have been the workhorses of snow removal for many years. Together, they help lower the freezing temperature of snow and slush, making it easier for the snow to be plowed away or worn down by cars before it turns into ice. But along with the good has come a great deal of bad. Besides keeping our streets clear, both chemicals can also pollute nearby waterways. They release chlorides and heavy metals into the environment and their corrosiveness can damage roadways, causing cracking and even potholes. So governments have been trying to find alternatives that can help remove the snow, and do less damage. Among those alternatives are snow and ice melters made of corn by-products. Ari Adler is a spokesperson for the Michigan Department of Transportation. He says the department is in the second year of testing those alternatives:


“In Michigan, what we’re doing is we’re actually applying this material by itself, preferably before a snowstorm hits. So it sort of puts like a Teflon coating on and what it does is not allow the snow and ice to bond with the pavement. So its certainly easier to clear away just from people driving over it or if we send a plow, it’s going to clear up quicker than if we had to send a team of plows out after we get snow pack out there.”


Adler says the tests so far have been very encouraging, and his agency plans to increase the use of such products in the future. Manufacturers of corn and soybean based de-icers say there is a growing trend to look to these more natural products. Craig Phelps is with Natural Solutions, a company that makes a product called Ice Ban. It’s made from parts of a cornstalk that are not used for food. The result is a liquid that melts ice and snow even at very low temperatures. Phelps says the product can be used alone, or in combination with salt. He says when used in combination, the product reduces the amount of salt required to keep roads clear:


“The way to decrease the effective use of chlorides is to somehow increase their performance or increase their range of activity. Using a liquid in combination with a granular, dry salt can help. Most highway departments have found they use less salt, so that does decrease the amount of accumulated chlorides in the environment.”


Phelps says the biggest obstacle in getting cities and states to use corn based de icers is the added cost. But he says in addition to the environmental benefits, corn based de-icers will reduce wear and tear on streets, bridges, and cars because it does not have the corrosive effect of salt. Phelps says if those costs are taken into consideration, the corn based products are actually cheaper than salt. But not everyone believes that is true. Dave McKinney is the Operations Director for the City of Peoria, Illinois’ Public Works Department. He says using salt is not a major cause for street repairs in midwestern cities:


“The problem we are having with streets isn’t so much the salt as it is the wear and tear of the freeze-thaw. So yes, there are these benefits, but I don’t think it can offset the cost. Certainly not in my budget.”


McKinney says he has tested the corn-based products, and is satisfied that they work well. But he says Peoria will only use them if the price comes down. And there may be evidence that will happen. The market for corn and soybean based de-icing products has increased by a thousand percent over the past seven years, largely because producers are finding cheaper ways to make the products. And as demand continues to increase, manufacturers say the price will keep dropping. For the Great Lakes Radio Consortium, I’m Jonathan Ahl.

Canada to Declare Road Salt Toxic?

Canada’s environment minister is recommending that road salt be classified as a toxic substance. The Great Lakes Radio Consortium’s Karen Kelly has details:

Transcript

Canada’s environment minister is recommending that road salt be classified as a toxic substance. The Great Lakes Radio Consortium’s Karen Kelly reports.


Approximately 5 million tons of road salt are used in Canada each winter.
And much of those salts eventually find their way into bodies of water.
The Canadian government recently completed a 5-year study of the environmental effects of road salts.


The scientists found water near some major highways contained as much salt as ocean water. And they concluded freshwater plants; fish and other organisms are being harmed. Canadian environment minister David Anderson has recommended road salt be added to Canada’s list of toxic substances.


But the government is not proposing a ban on salt. Officials are studying ways to reduce its use and improve snow removal techniques to minimize the amount of salt escaping into waterways. The public has 60 days to comment on the plan. For the Great Lakes Radio Consortium, I’m Karen Kelly.

New Alternative to Road Salt

Snowy, icy roads are a fact of life around the Great Lakes. For years,
de-icing salt has been the weapon of choice to keep roads passable
during the winter months. But the runoff from road salt can pollute
surface and ground water, contaminating wells and causing problems for
fish populations. So researchers have been looking for alternatives.
And now, there’s a new one that looks promising. The Great Lakes Radio
Consortium’s Wendy Nelson reports: