GRAND JUNCTION, Colo. (KREX) — A bridge over Blue Mesa Reservoir 18 miles west of Gunnison was closed indefinitely on Thursday due to cracking. The closure will delay travelers from other towns in western Colorado hoping to reach Gunnison and surrounding areas.

State inspectors “identified anomalies in the bridge,” according to the Colorado Department of Transportation. In a release, CDOT said, “This inspection was required because of known issues with similarly constructed bridges elsewhere in the country.” This requirement was created by the Federal Highway Administration.

UPDATE: A routine inspection late last week revealed a tiny crack only about four inches long in the steel of the bridge. CDOT crews took a closer look and studied the bridge with a sonar device revealing a much bigger crack inside the steel.

Officials don’t know when the bridge will reopen. CDOT says more testing needs to be done to find out the true extent of the damage.

Locals will be allowed over the bridge to reach their homes on the other side, but other drivers will need to plan an alternate route. The recommended alternate routes are I-70 through Vail to the north adding six hours of travel time or U.S. 160 through Pagosa Springs to the south adding seven hours of travel time.