Work began Thursday morning in Farmingdale to repair an underground drainage structure that washed out a section of road at Northern Avenue and U.S. Route 201 north of the Gardiner town line, according to the Maine Department of Transportation.

Two lanes of traffic will be maintained throughout the day. Starting at 8 p.m., there will be a single lane of alternating one-way traffic controlled by temporary traffic signals, the department said.

Traffic is expected to be back open to two lanes by 7 a.m. Friday, with work continuing through Saturday, the department said.