Mag vs. sand: What’s better?
Aspen Times Staff Writer
Basalt isn’t buying the Colorado Department of Transportation’s slick new campaign touting the use of magnesium chloride.
In its first winter as owner of Two Rivers Road, the town of Basalt has expanded its ban of mag chloride to the sensitive roadway. The council ruled in the late 1990s to stop using the liquid de-icer on its streets.
The debate of mag chloride versus sand and gravel was never so relevant as with Two Rivers Road. It is perched over the Roaring Fork River for most of its three-mile distance. Any substance used to treat ice is certain to make its way down an embankment and into the crystal-clear waters of the river. Sand and gravel will get kicked off the shoulder just as easily as mag chloride will slop over the edge.
Critics assail mag chloride for causing vehicles to rust quicker. There is also a huge but unresolved debate over its health and environmental effects.
Sand and gravel bring different problems. Heavy use on places like Vail Pass on Interstate 70 has clogged streams and threatened aquatic life.
CDOT has embarked on a campaign this winter to try to win more widespread support for continued and increased use of mag chloride.
While the Basalt government has taken a stand against use of mag chloride and other chemicals like herbicides, it hasn’t debated what effects gravel has on air and water quality, acknowledged Councilwoman Jacque Whitsitt, an outspoken foe of mag chloride.
That’s a topic that should be considered, said Lee Cassin, environmental health director for the city of Aspen. She believes governments are asking the wrong question when they try to decide whether they should use mag chloride or sand. They should be asking what alternatives are available, she said.
Cassin is a proponent of acetate de-icers. They can be used at colder temperatures than mag chloride, and research shows they don’t have as great of environmental consequences, she said. Acetate de-icers are used at the Pitkin County Airport.
Their drawback is their price. They are significantly more expensive than mag chloride, Cassin said. But when corrosion and environmental impacts are factored in, she believes the price of acetate de-icers can be justified.
“I think the key is spending the money to do it right the first time,” she said.
Despite her best efforts, she wasn’t able to convince Aspen to go that route. Aspen, like Basalt, prohibits use of mag chloride and uses sand and gravel. The city of Aspen constantly sweeps its streets to avoid adding to its air quality problems.
Basalt assistant manager Betsy Suerth said the town purchases three-eighths-inch rock that has been washed free of contaminants to try to minimize environmental effects. The town public works department also uses the gravel sparingly on Two Rivers Road as a way to protect the river.
As drivers can attest, the public works crew has dialed in its approach to Two Rivers Road this winter. Use of gravel was heavy during the first few storms. Gravel has been used more sparingly since.
Kristine Crandall of the Basalt-based Roaring Fork Conservancy agreed with Cassin that both mag chloride and sand have their drawbacks. Their impacts on the river and environment really can’t be judged without studying application rates and amounts, she said.
“From the Conservancy’s perspective, all deicers have the potential to enter waterways, raising concerns about pollution impacts,” Crandall said. “This is a type of storm water runoff, an issue that we have been trying to heighten awareness about in communities throughout the valley, encouraging proactive best management practices.”
Overall, she said, the best practice would be using de-icers sparingly and in minimum concentrations.
Whitsitt said she could support limiting sand and gravel to key places and asking drivers to slow down and take proper winter precautions. “I have no problem dumping a few grains at stop signs and stop lights,” she said.
[Scott Condon’s e-mail address is firstname.lastname@example.org]
Yet another incident involving a semi-tractor trailer losing it on the snow-slick roads in Glenwood Canyon has both the westbound and eastbound lanes of Interstate 70 closed east of Glenwood Springs as of 11:15 a.m. Monday.