With miles of Interstate 84 between Nampa and Caldwell and a stretch of Meridian Road in Meridian both closed so crews can do emergency road work due to potholes, transportation experts are warning Idaho drivers to be watchful for potholes, especially along older sections of roadways.
During times of high moisture and multiple freeze-thaw cycles -- much like has been experienced throughout many parts of Idaho in recent weeks -- older sections of roadway often show sign of stress with potholes and broken pavement, according to the Idaho Transportation Department.
Potholes and areas of major breakup develop as water seeps into cracks and saturates the base material below the roadway surface. Ice expands in the cracks and base material, loosens the road surface, and it collapses as it melts and traffic drives over the top.
“There is usually enough time during most winter storms for our road maintenance crews to complete repairs,” ITD Chief Highway Engineer Kimbol Allen said. “So far this winter season, however, crews have had little time between storms to do much more than prepare for the next storm to hit.”
Potholes are a common problem in older or stressed roadways, generally seen during late winter as temperatures begin to rise above freezing. However, the abundant moisture coupled with a wide range of temperatures has created similar conditions and widespread roadway breakup, ITD said.
During winter storms, the first priority of ITD crews will be to clear snow and ice from the roadways.
Attention to potholes is a secondary duty for crews to fill them with temporary patching material -- but continued moisture quickly loosens and breaks up the patches. Only after the potholes are able to dry completely can a more durable patching material be used and be expected to last. Other secondary duties include guardrail repair, sign repairs or replacement, and equipment repair, ITD officials said.
Drivers are reminded that potholes and other broken pavement sections are considered roadway hazards, so drivers need to take extra precautions to avoid hitting these spots.
Potholes and roadway hazards are often marked with roadway breakup signs or hazard markers. Drivers should watch for roadway breakup signs in areas of major break up or smaller, diamond-shaped signs to signify areas of breakup, eroded shoulders or other hazards.