During December's interesting weather, I noticed the gravel that was spread on my rural county road looked suspiciously like red cinder rock from somewhere east of the Cascades. Maybe you guys can find out where that rock really comes from? Is there something about it that makes it the perfect material for icy roads? I hope we're not hauling rock all the way from Eastern Oregon.
— RRBill, Rogue River
We've wondered the same, RRBill, so were happy to check it out for you.
For your question, we turned to John Vial, Jackson County Roads and Parks Department director, and he came up with even more details than we could have imagined.
First of all, he assured us, the material is not from some distant spot in Eastern Oregon. The cinders that Jackson County purchases, he wrote in an email, as well as that applied by local state crews, come from a few different quarries between Medford and Klamath Falls.
Vial also noted that while many people refer to roads being "sanded" when it's icy, there's actually little sand. He said while local crews also use a mix of sand and gravel at times, the cinders have several advantages.
First, he said, the size of cinders are typically larger than the sand and gravel and have lots of "edges." When applied to a snow-packed road, they provide superior traction. Cinders are also lighter and softer than gravels. As a result, they tend to cause much less damage to vehicles.
Also, because of their lighter weight and porous nature, the cinders do not tend to pack and freeze inside the truck beds.
Vial said in the aftermath of the Dec. 5-6 storm and through the extended cold period that followed, Jackson County applied more than 3,300 cubic yards of cinders, sand and gravel to county roads, with a total cost of $60,000 for the material alone.
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