About 4,900 vehicles travel through Greensburg on an average day, including 1,700 commercial vehicles.
But as hundreds of emergency workers and residents sift through their flattened city, traffic on U.S. 54 is being rerouted around on both sides, a Kansas Department of Transportation official said.
Westbound traffic is being stopped in Pratt, which is 30 miles east of Greensburg.
State transportation workers are directing people headed toward Dodge City or beyond north to Highway 281 and then on to U.S. 50, which leads to Dodge City.
Traffic headed toward Liberal is being rerouted south on highway 281 and Highway 160, a detour that makes the trip between Pratt and Liberal about 40 miles longer.
Eastbound traffic is being stopped at U.S. 183, about a mile west of Greensburg. From there, people can connect with U.S. 160 or U.S. 50.
It's unclear when normal traffic will resume. All the detour roads can handle the same types of traffic and vehicles that U.S. 54 can.