I-70 and the Sinkhole in Russell County

Geological Marvel Threatened Pavement

Two active sinkholes in Russell County forced engineers to alter their plan for reconstructing a short stretch of I-70. Because of unsuccessfully plugged oil well shafts that were abandoned in the 1940s and 1950s, water moves between underground layers and has found a layer of salt 1,300 feet below the surface. As the salt dissolves away, the ground above it sinks and takes with it the asphalt surface of I-70.

The problem was first discovered in 1966 when I-70 was being built. Engineers had graded the dirt to what they thought was the final grade before beginning the paving process but the grade was lower a few months later. As a result, the roadway has been raised and resurfaced a number of times as the ground beneath it sinks. A county road bridge over the highway was also sinking and prevented raising and resurfacing I-70 in 2004 because the clearance under the bridge was not sufficient. In 2004, the bridge was removed, new surface drainage was constructed, and the highway was again raised to the proper level.

The area is dubbed the most surveyed piece of ground in Kansas as geologists and engineers document elevations in the area every six months. The gradual sinking occurs at a rate of 4-5 inches per year.