Work starts Wednesday to repair a stretch of Kennewick’s Ridgeline Drive damaged by heavy rains last week.
The city closed Ridgeline between Clodfelter and Clearwater at Badger Canyon in far western Kennewick late last week after it discovered that saturated soil had settled in trenches carrying water and sewer lines serving the area. The settling threatened pavement and created dangerous road conditions.
The stretch, which is not the stretch near Southridge High School, remains open to a local church and neighborhood. However, the 3,100 daily drivers who use it are asked to use other routes.
The city began moving repair equipment, including excavators, to the site on Monday.
Bruce Mills, Kennewick’s deputy public works director, said city crews will excavate the trenches, remove water and rebuild the roadbed with fresh rock. A contractor will repave it since the city doesn’t perform actual paving work.
The water and sewer lines were not threatened by the failing trenches, he said.
The stretch of road is relatively new, but Mills said it isn’t a case of a bad design. Water infiltration is a challenge in western Kennewick, where shallow soil overlays basalt rock below.
Water doesn’t percolate well, Mills said. The city is trying to figure out longer-term drainage solutions as the western end grows.
“As that area develops, we don’t want to continue to put in the wrong treatment,” he said.