CLEARFIELD — The Pennsylvania Department of Transportation announced that Route 155 will not be completely closed while the bridge over Birch Run is replaced.

The bridge is approximately two miles southeast of Turtlepoint in Liberty Township. Replacing the bridge will allow PennDOT to remove it from McKean County’s list of bridges in poor condition.

Temporary signals have been installed and are currently operating in flash mode. They will be fully operational Monday, at which time they will enforce an alternating traffic pattern as the bridge is replaced in a half-width configuration. Under the alternating pattern, the northbound lane will be closed, and drivers will take turns crossing the bridge in the open southbound lane. There is a 12-foot lane restriction in place for the open lane. PennDOT will issue an update as work progresses and the traffic pattern changes.

The existing 17-foot bridge was built in 1924 and carries an average of nearly 3,000 vehicles per day. The overall project will replace the existing structure with a precast box culvert, widen the roadway, improve drainage, replace guiderail and install new signage.

Francis J. Palo Inc. of Clarion is the contractor on this $796,000 job. PennDOT expects to complete the project by late August. All work is weather and schedule dependent.