A section of County Road 21 located north of Kathryn, North Dakota, experienced pavement distress triggered by heavy rain events. Barnes County applied to Emergency Relief Program through the North Dakota Department of Transportation. The repair was funded through the program as project CER-0221(080). 

The advancing hillside distress lead to closure of the northbound lane in an area with a history of slope instability. Previously, several small unsuccessful attempts to address the ongoing stability concerns were made. Braun Intertec was retained by Barnes County to perform a comprehensive study of the area, evaluate the hillside and recommend a permanent solution. The geotechnical evaluation included soil borings, installation and monitoring of inclinometers and piezometers, laboratory testing, and geotechnical modeling to evaluate several options for repair. 

Based upon the progressive historical failures and existing repair attempts, the County decided to over-excavate the affected area and install subsurface drainage, backfill the roadway and construct a toe berm near the primary area of instability. Braun Intertec also supported the project throughout construction. Work included excavation oversight, compaction testing, laboratory testing of construction materials, and asphalt pavement testing.