A portion of sidewalk on Gekeler Lane between 18th and 20th streets recently buckled. (Dick Mason/The Observer)
Island City is not alone on the buckling sidewalk front in Union County.
Buckling sidewalks have been spotted in Island City but they also can be found in La Grande.
A number of sidewalks have buckled in south La Grande in recent weeks, all but one in minor fashion, according to City of La Grande Public Works Director Norm Paullus.
“Sidewalks in the south side of town are more prone to this because of expansive soils,” Paullus said.
“Expansion of the soil when it gets wet can cause sidewalks above it to rise,” Paullus said. Some soil under sidewalks may be expanding now because of people watering their lawns and gardens.
The expansion of this water-saturated soil is greater the hotter the weather, meaning portions of some sidewalks are elevated a half inch during the day and then come down when temperatures cool at night.
The sidewalk buckling problem in La Grande is a minor one except at one site on the north side of Gekeler Lane between 18th and 20th streets. A sidewalk panel there has popped up about four inches and cracked as a result.
“We are watching it closely,” Paullus said.
If the panel does not come down later this summer after the weather cools it may be removed and replaced.
Paullus said this would be the best option because if the sidewalk does not come down, then the soil under it is expanding because of water the soil is continuing to absorb. If this is the case, a public works crew will remove the sidewalk panel replace the soil underneath with crushed gravel. A new sidewalk panel would then be installed.
Paullus said some portions of sidewalks may be buckling because heat is causing their concrete to expand. This causes panels to push against one another, the force of which results in them popping up.