Use of de-icer on roads defended
Thursday, December 15, 2011 | 4:11 pm
Paul Tounsend of Snohomish writes: The state Department of Transportation puts de-icer on the roads through the passes in the winter. This liquid is very corrosive, it will rust out a truck in two to three years - the brakes, exhaust system, drive lines, etc. It would be better to use sand.
Bronlea Mishler, spokeswoman for the state Department of Transportation, responds: When winter weather hits, state transportation maintenance workers have a variety of tools at their disposal to get the roads back to bare and wet as soon as possible.
During snow and ice, maintenance crews have to pick the best tool for the job. This includes anti-icers (liquid chlorides such as magnesium chloride, calcium chloride or sodium chloride) that are applied to the highway before snow hits. These chemicals lower the freezing point of water and prevent ice from forming on the roads. Crews can also use de-icers such as salt or a sand-salt mix.
All the liquid anti-icers we use are corrosion inhibited – which is a fancy way of saying they're treated with agricultural by-products (such as sugar or molasses) so they're 70 percent less corrosive than straight salt. We treat all of our salt and salt-sand applications with corrosion inhibiting liquids, too, just to make sure there's a level of corrosion prevention there.
Since our goal is to get the roads back to bare and wet as soon as possible, we need to use de-icer or salt to meet that goal. Sand has no ice melting properties and can only act as a traction aid as long as it stays on the road – which in most cases isn't that long.
With heavy traffic volumes, the sand often gets blown off the road quite quickly. Additionally, sand often winds up in salmon-bearing streams, which can bury habitat and can also create some serious air quality issues after we apply it multiple times.
On the other hand, anti-icers and salt are used in low enough concentrations to not affect water or air quality the way that prolonged and repeated use of sand does. The transportation department measures chloride levels in soil and water in many locations around the state every year, before and after winter. To date, we've noted no significant or reportable increases.
Howard Bird of Sultan writes: I read in The Herald that the county has received a federal grant to upgrade the striping on select county roads. This striping is raised and has the effect of a rumble strip. One of the roads they have selected is 311th Avenue SE north of Sultan. I just don't see that there is enough traffic on this road to warrant the upgrade. I don't recall any crossover accidents on this road.
Another of the roads selected was Ben Howard Road near Monroe. What criteria did the county use to make these selections? These two selections don't seem to make much sense from my point of view.
Owen Carter, Snohomish County engineer, responds: Ben Howard Road and 311th Avenue SE, south of Sultan, form a roadway network that connects U.S. 2 to Highway 203 near Monroe. Both of these roads are classified as major collector roads - the highest arterial designation in the unincorporated Snohomish County rural area.
Snohomish County was requested to submit a project where the improvements would reduce the number of single vehicle, run off the road collisions. Ben Howard Road was chosen because of the number of collisions, horizontal and vertical curve issues, and because it is heavily shaded and in places almost tunnel like.
Since 311th Ave SE connects to Ben Howard it made sense to submit both roads as a network for the grant and we were successful in receiving the funds.
E-mail us at stsmarts@heraldnet.com. Please include your city of residence.
Bronlea Mishler, spokeswoman for the state Department of Transportation, responds: When winter weather hits, state transportation maintenance workers have a variety of tools at their disposal to get the roads back to bare and wet as soon as possible.
During snow and ice, maintenance crews have to pick the best tool for the job. This includes anti-icers (liquid chlorides such as magnesium chloride, calcium chloride or sodium chloride) that are applied to the highway before snow hits. These chemicals lower the freezing point of water and prevent ice from forming on the roads. Crews can also use de-icers such as salt or a sand-salt mix.
All the liquid anti-icers we use are corrosion inhibited – which is a fancy way of saying they're treated with agricultural by-products (such as sugar or molasses) so they're 70 percent less corrosive than straight salt. We treat all of our salt and salt-sand applications with corrosion inhibiting liquids, too, just to make sure there's a level of corrosion prevention there.
Since our goal is to get the roads back to bare and wet as soon as possible, we need to use de-icer or salt to meet that goal. Sand has no ice melting properties and can only act as a traction aid as long as it stays on the road – which in most cases isn't that long.
With heavy traffic volumes, the sand often gets blown off the road quite quickly. Additionally, sand often winds up in salmon-bearing streams, which can bury habitat and can also create some serious air quality issues after we apply it multiple times.
On the other hand, anti-icers and salt are used in low enough concentrations to not affect water or air quality the way that prolonged and repeated use of sand does. The transportation department measures chloride levels in soil and water in many locations around the state every year, before and after winter. To date, we've noted no significant or reportable increases.
Howard Bird of Sultan writes: I read in The Herald that the county has received a federal grant to upgrade the striping on select county roads. This striping is raised and has the effect of a rumble strip. One of the roads they have selected is 311th Avenue SE north of Sultan. I just don't see that there is enough traffic on this road to warrant the upgrade. I don't recall any crossover accidents on this road.
Another of the roads selected was Ben Howard Road near Monroe. What criteria did the county use to make these selections? These two selections don't seem to make much sense from my point of view.
Owen Carter, Snohomish County engineer, responds: Ben Howard Road and 311th Avenue SE, south of Sultan, form a roadway network that connects U.S. 2 to Highway 203 near Monroe. Both of these roads are classified as major collector roads - the highest arterial designation in the unincorporated Snohomish County rural area.
Snohomish County was requested to submit a project where the improvements would reduce the number of single vehicle, run off the road collisions. Ben Howard Road was chosen because of the number of collisions, horizontal and vertical curve issues, and because it is heavily shaded and in places almost tunnel like.
Since 311th Ave SE connects to Ben Howard it made sense to submit both roads as a network for the grant and we were successful in receiving the funds.
E-mail us at stsmarts@heraldnet.com. Please include your city of residence.
Most recent Street Smarts posts
Comments
(
