WLC Engineering and Surveying was hired by Carbon County Road and Bridge to perform an evaluation and design road repair for Carbon County Road 401 (Sage Creek Road), located south of Rawlins, Wyoming, and stretching approximately 50 miles. The paved road had received a chip seal in 2024. The heavy truck traffic from the chip seal, combined with a soft subgrade, resulted in several areas along the road developing severe rutting and pavement lift delamination.
WLC investigated the failures, identified a soft subgrade and a thin pavement section as contributing factors, and prepared repair recommendations. As a result, WLC partnered with JB Engineers to drill to a depth of up to 15 feet at the failure sites. The original design accounted for only 3–4 heavy trucks per day and included 6 inches of base course and 3.5 inches of asphalt. However, the failures were ultimately caused by a combination of a weak subgrade, heavier-than-anticipated truck traffic, and separation between pavement layers.
To fix the problem, WLC’s recommendation included removing 2 feet of material, adding geogrid for stability, installing a 2-foot base course, and finishing with 4 inches of asphalt pavement.
Additional services provided by WLC included support throughout the bidding process and administration of the construction contract. WLC’s team worked with the contractor during construction to evaluate each failure area to determine if efficiencies could be realized once the areas were excavated. The scope of the road repair was reduced in several areas, thereby reducing the cost to the County.
