The “before” photos of this project are not a pretty sight. A river running below this Washington road had undermined the base of the slope, while runoff had heavily eroded an extremely steep hillside above the road.
“Between the hydraulics created by the hill on the back side and the river underneath it, half of Cline Road just washed out,” explained a local manufacturer.
Cline Road was partially closed for nearly two years before the county secured funding to repair the failed roadway in 2011.
Searching for a retaining walls system that could build a 13.5-ft-tall wall without requiring extensive excavation, the county turned to Redi-Rock.
County engineers designed the retaining wall using 3,420-lb 60-in. base blocks for the bottom two courses of the wall. The middle portion of the wall was designed with 41-in. middle blocks (weighing as much as a Budweiser Clydesdale), and the very top course was designed using 28-in. top blocks.
The blocks were available in three natural stone textures—including Limestone, Cobblestone and Ledgestone. For this project, a two-tone gray Cobblestone block blended nicely with the rip-rap.
After two years of waiting for Cline Road to completely re-open, the 1,185-sq-ft wall was installed in just five days in July 2011—and the roadway opened shortly thereafter. The gravity walls are very efficient to install. Each massive block is set in place using an excavator and 1-2 person crew. Since excavation is minimized, valuable time and money is saved on the installation phase of projects.
