Road crews prepared for pavement bleeding

Road sanding, though most often associated with winter driving conditions, is something Washington County Land Use & Transportation Operations and Maintenance crews are preparing for, should pavement bleeding result from prolonged high temperatures.

"Bleeding" is the term used for the shiny, oily-looking film of asphalt binder that appears on a road during prolonged periods of high temperatures. Bleeding can cause roads to become somewhat slippery, which road crews control by applying sand.

"Pavement bleeding can occur on chip seal road surfaces, and it starts to be a concern when we have a number of days with temperatures of 95 degrees and above," said Keith Lewis, Operations Superintendent. "If we have three to four days of 95-degree heat we start to watch for it."

The likelihood of bleeding depends on several factors including how much exposure a road has to direct sunlight, how much radiant heat the asphalt holds after the sun goes down and the percentage of oil in the road surface. Heavy truck traffic, which draws more oil to the surface, can also be a factor.

"Some summers, we have none," Lewis said. "Temperatures have been moderate so far, but July and August are often pretty hot. We always prepare for the worst."

When temperatures are high and roads appear oily or sound "tacky" when tires travel over the surface, travelers should use caution. To report hazardous road conditions during normal business hours (8 a.m.-5 p.m. Monday-Friday) call 503-846-ROAD (846-7623), e-mail or submit an online service request. Outside of normal business hours, call Washington County non-emergency at 503-629-0111.