Many years back I was on a trip to New England and came across a road which seemed to be covered with gunk and grit. “They’re oiling the roads,” somebody said, and for some reason I didn’t ask what that meant, at the time.
But what did that mean? Do they still do that? Is it really OIL?
They still do it here in Colorado, on unpaved roads. It keeps the dust down.
Dirt roads are often oiled to keep dust down but I haven’t seen that in Arizona in several years. Yes, oil. It works better than cottage cheese.
FWIW some so called pavement, chip seal, is just gravel spread and coated with heated heavy oil that soaks in and hardens. Not the same as true asphalt paving. Might be more likely that is what you saw.
Gravel or blacktop?
They did, indeed, formerly use oil as a dust suppressant on gravel roads. (If you’ve ever lived on a gravel road where traffic tends to go over 25 mph you’ll understand why. Try living through a hot summer (pre-air-conditioning) with the windows closed to prevent every speck of food or newly washed clothing from being covered in grit.)
With the environmental wake-up calls of the late 1960s, oil has generally been discontinued and a calcium chloride/water solution has been substituted. I suspect that oiling gravel roads is now illegal at the Federal level, akthough there may be some places that continue to do it.
On blacktop roads, a common routine maintenance procedure is called (at least in Ohio and Michigan) chip and seal. The road is sprayed with oil and a thin layer of crushed (chipped) stone is spread across it. The traffic then rubs the stone into the oild, creating an additional layer over the original asphalt that (theoretically) add a few years to the life of the road surface.
It is possible (though I do not know how often it occurs) to create a chipand seal road without an asphalt bed. In that case, stone is laid on the gravel and oil-sprayed and an additional layer of stone is put down.
Depending on the perverse humor of the local road crew, it is also possible to simply lay down a sheet of oil on asphalt in the manner of a homeowner applying sealant to an asphalt driveway. That is the worst to drive over because most of it simply becomes the undercoating of any car that travels the road before the oil hardens.
Oh, you’re probably right about the change in what they put on the roads here, come to think of it. I haven’t lived out in the boonies for awhile, and while I’ve seen some roads being treated recently, I wasn’t close enough to smell it.
I don’t know if any counties would have actually put oil down for dust control,it’s possible I guess.I know here in Oilberta lots of farmers used to put used oil on their driveways and roads near their acreages,as did many contractors in their yards.Very hefty fines for that these days.
Calcium is used for this purpose now and I have also seen tree sap being used as well.
Anything you see being used in a construction zone is asphalt oil,which is very different from ordinary oil.It’s very heavy and thick and is handled at fairly high temperatures.
Tom,most likely the oil you saw wasn’t the final step.When re-surfacing asphalt they spray the old stuff,then pave over it,which makes the two bond together.You will see crews putting just oil on cracks in old asphalt at times.
Of course,what I know was learned in Alberta and may be different elsewhere.
The local horse racing club once used oil to keep down dust on the vehicle track used by ambulances to chase each race.
The dust is controlled effectively, but the oil/sand mix sticks to the underside of the truck like shit to a blanket. Despite the passing of several years since the oil was laid, evena high pressure cleaner is not totally effective to get this stuff off.
You guys who posted above must curse those roads every time you drive on them.