Residents dig their cars out of the snow in Annandale, VA, on December 19, 2009. The runoff from deicers used to clear ice and snow from roadways and sidewalks can damage water supplies and ecosystems. This excerpted CAP guest post was first published here.
The winter season means holidays, vacations, and family time, but it also means the arrival of something else: snow. It may be beautiful as it’s falling, but dealing with the aftermath of a large snowstorm can be hard work. Ice and melting snow on sidewalks and streets creates hazardous conditions, but that doesn’t mean clearing it has to be harmful to the environment.
Chemical deicers such as sodium chloride, calcium chloride, and magnesium chloride are often applied to frozen roadways and sidewalks in rock salt form to make shoveling and clearing them easier after a big snow. The compounds form a brine solution that works by breaking down the molecular bonds that hold ice to cold surfaces, melting the snow as the reaction occurs. But as the brine continues to seep downward into the ground, the runoff is introduced into the ecosystem, which can damage surrounding grass, trees, and other plants before making its way back into the water supply, where it can cause further harm to plants, animals, and people who drink or use the water.
Studies on the effects of road-salt runoff in fresh water streams in Minnesota found that prolonged, high-dose exposure to the runoff was lethal for certain species of fish and insects. The studies also found that salts could damage or kill roadside grass, plants, and shrubs, all of which provide valuable ecosystems and erosion control. Excessive sodium levels in soil can change the soil’s chemical makeup and render it unable to retain water and therefore grow much of anything.
What’s more, these chemicals don’t just harm living organisms; the corrosive agents in road salts can damage and shorten the lifespan of roads, sidewalks, and other structures, creating the need for costly and nongreen-friendly replacement. One estimate places the costs of damage between $40 and $90 per ton of applied salt.
To minimize the damage done by chemical deicers, only use them in conjunction with snow removal. Shovel and sweep away as much snow as possible before applying deicer to your sidewalk or driveway, using the deicer only to break up the last layer of packed snow or ice. Mixing a half sand-half deicer recipe will minimize the amount of product needed as well as reduce the harm to the environment while providing traction and safety. Follow the instructions on the packaging to be sure you are not overapplying deicer and increasing the risk of harm to the environment.
Opt for a calcium magnesium acetate-based product since those formulas are salt free and have a lower likelihood of damaging plants and soil, as well as concrete surfaces. Other volcanic-based products are reusable and offer the same ice melting and traction properties without the harmful side effects, ensuring your grass and plants are around for holidays in the years to come.
Read more articles from the “It’s Easy Being Green” series
Previous in TP Climate Progress
Language Intelligence: Lessons on persuasion from Jesus, Shakespeare, Lincoln, and Lady Gaga
“I think that people are justified in being disappointed about the outcome in Copenhagen,” the president said today during an interview with PBS’s Jim Lehrer, “What I said was essentially that rather than see a complete collapse in Copenhagen in which nothing at all got done and would have been a huge backward step, at least we kind of held ground and there wasn’t too much backsliding from where we were. It didn’t move us the way we need to.”
Thanks Obama.
Now for the blizzard we face. Salt sand blemds seem to help traction. I am watching a blizzard and suspect visibilities will keep driving speeds very low. I have a very close friend that was a VP at a salt company. It appears they can’t find any weed kill in ditches where roads had heavy salt. If they did, it would save money on mowing the next summer. I advocate salting roads and helping protect driver safety..
good info – the sidewalks around where I live get covered in salt and blue with de icer if there’s even a chance of snow. I see the blue stuff seems to be the better choice.
Salt and blue stuff and everything else gets washed into the water column come melt time and can effect the wildlife, fish, frogs, etc with a spike in salinity, anti-freeze etc. that may or may not be survivable by said critters.
Seems like we need to toughen up a bit. How did every previous generation survive while using a tiny fraction of this stuff?
When walking, shorten your stride. There are goulashes and strap-on spikes or cables to help with walking. The right boot or shoe tread for the right snow or ice conditions is also helpful.
The same with biking on snow and ice – you want experience and in icy conditions there are studded mountain bike tires.
I’ve been a ski race coach on weekends for ten years and writing about World Cup ski racing for three times that long, and my favorite tires for not doing damage are studless snow tires. I put all-season radials on from my last expected snow drive to my first the following fall. I’ve used tires for over half a dozen years as a result.
Since studded snowtires damage roads I’ve never used them and rarely use chains – only once in 20 years of Colorado mountain driving. And I’ve used mostly front-wheel drive cars, all economical like a 1989 Honda CRX with no problems.
I don’t expect any sidewalk or road to be ice-free, but adapt and have never had problems in thousands of miles of mountain walking, biking and driving on snow and ice.
So I think we can all slow down, choose our trips and equipment carefully, and toughen up a little.
funny, how does CAP write a report like that and NOT mention the biggest danger to salt on the roads is to your car. Give it a week folks, and it will melt. No need to rust up the car.
Yikes – this is scary.
Those who believe that CMA blends do not contain salt, will also likely believe that they can put a thimble of gasoline in a gallon of water and drive any car. That’s the chemical equivalent analogy and the “green sheeple” are believing this stuff without any facts to back it up.
CMA is a very expensive material to manufacture and costs about $2/lb, or roughly $100/bag for the deicer. The minimum amount of CMA needed to simply inhibit the chloride attack of salt is 400,000 parts per million. 99% of all deicers claiming to be “CMA Based” contain 500 ppm or less, which is a fraction of a percent (0.00125) of the minimum that is required to be effective; substantially less than a thimble of gasoline in a gallon of water. Want to know what the other 99.98% of that CMA based deicer is? Yup, you got it – it’s SALT. This all about money and deception at the expense of those of you who are so wanting to do the right thing environmentally, that you blindly accept statements without examining facts.
Think about it in this context: If I drove up with a 6,000 lb. SUV and said it is a hybrid, and you drove up an electric car, does that make them both equal? Of course not. These 6,000 lb. hybrid behemoths are getting 15 mpg instead of the regular 13.5 mpg so that makes them environmentally green and friendly? Same thing is happening on this whole CMA blend thing and people are just buying right in.
As Jeff Foxworthy would ask: “Are you smarter than a 5th grader?” This is really nothing more than 5th grade science; we are lowering the freeze point of water – we are not shooting rockets to Jupiter so the concept that an ice melter formula is “secret” is ludicrous. The only secret is that you are paying $10 for a $2 bag of salt dyed green with nice earth pictures on the bag. No wonder they want to keep that a secret!
The great CMA sham in packaged deicers is shameful and the green public is being victimized by it. The public needs to demand full disclosure and truth in labeling on packaged deicers in order to know that the “green” product you are buying is more than money in the pocket of the seller. If you can’t find a full list of ingredients showing the actual percentages of each about any deicer you should be very suspicious.
Because someone says something is green does not make it environmentally better. Examine the chemistry, do your homework, and, demand full disclosure and quickly those who buying products they think are better for the environment will find that they are simply lining the pockets of deceptive marketers with green – not improving their environment much at all.
While we’re on the subject, the claims of certain “magical” salt products being completely biodegradable are also poppycock. If you can make the inorganic compound sodium chloride biodegrade, you are a walk-in for the Nobel Prize in Chemistry. If you can put something down on the ground that “melts the first 2-3″ of snow”, you can get a two-fer with the Nobel Prize in physics too for defying gravity. What material melts up?
P T Barnum was not wrong.
Do your homework and use your noggin. Do not accept claims if they are not backed up by facts, figures, and clear definitions.
Now, who wants to play three card Monty for $50?
Salty: Good call on deicers. Also powerful testimony to the power of advertising. The same people that convinced a large portion of the American population that the best approach to moving of a few hundred pounds of carbon based life forms from place to place is 6,000 pounds of steel in the form of a 40 to 100K+ dollar SUV. A bicycle will do that for a few hundred dollars and save you a stroke in the bargain.
Salty and Leif (and I guess salty leaves are another byproduct of de-icers) have hit the nail on the head. The environmental damage listed above is a byproduct of nearly a billion internal combustion engine vehicles averaging at least a couple of tons each, often carrying one person and little else.
The arguments about whether we should have a billion electric vehicles or a billion hydrogen vehicles seem to miss the point. Are a billion vehicles of any kind remotely sustainable? Is there enough lithium or substitutes to power a billion electric vehicles needing battery replacements every so often?
It seems the best we can aim and hope for is the European/Japanese model of greater density with far superior rail traffic.