On 18 March 2020 at 13:09:31 UT, an earthquake damaged Salt Lake City International Airport, and threw air traffic in the Mountain States into further disarray. The 5.7 magnitude wobbler and its aftershocks made the Delta Airlines hub temporarily unusable, though the airport resumed limited operations after several hours.
Most airports in South Dakota, Montana, and Wyoming that rely on the Salt Lake City hub still have a flight to another Delta hub. Casper and Cody don’t, but are also served by United out of Denver. Butte’s only scheduled passenger flights are to Salt Lake City.