Repairs will address the sliding base of US-95 at milepost 518 near Rock Creek. They will go to bid in late summer with the goal of construction in fall 2019.
To fix the road, the failed material will be removed, and rock will be placed to improve drainage. Drains and a reinforcing grid will also be installed.
Following the April 2017 slide, barrier was placed near the edge, and the highway was widened to maintain two lanes. Barrels separated the lanes, and an advisory speed limit of 35 mph was put in place. A geotechnical investigation helped ITD develop the plans and understand why the hillside was moving and to what extent.
In spring 2019, delineators were added to make the concrete barrier more visible, and a regulatory speed limit of 45 mph replaced the advisory limit.
Although the department typically sets design and construction schedules for projects, emergency repairs set their own.
After a slide, state forces are immediately activated to open as many lanes as safely possible. The initial response is the quickest part of the process, as extra steps must be taken in order to successfully obtain federal aid for permanent repairs. They include installing devices to monitor conditions, securing design approval, acquiring any land needed, etc.
In general, repairs to slides that are still slowly moving, to areas still expected to receive significant moisture or to sites with a high water table are not likely to last.
These factors can significantly affect drivers and the schedule of repairs, whether they are big or small. In order to maximize external and internal resources, ITD must wait until conditions are right.