Crawford sinkhole, Russell County

The Crawford sinkhole, which causes Interstate 70 to sag west of Russell, has been linked to an improperly plugged and abandoned oil well. Because the well was not adequately sealed, groundwater leaked along the well casing into the Hutchinson Salt Member about 1,300 feet below the surface. An underground void was created where the salt dissolved, the surface slumped into the void, and groundwater pooled in the resulting dip.

Not until after I-70 was completed in the area in the 1960s did the state suspect that the pond was a sinkhole. Since then, the Kansas Department of Transportation has repaved the road on occasion to eliminate the dip but was unable to rescue a nearby overpass. Over 40 years, one corner of the bridge had dropped more than six feet, limiting tractor-trailer truck clearance whenever the road was resurfaced and raised. For safety reasons, the bridge was blown up and removed in 2004.