Work on new sidewalks and traffic lights at routes 1 and 27 in Wiscasset is going well overall, but a delay in one key piece means the lights won’t go on until the latter part of July, project manager Aurele Gorneau of the Maine Department of Transportation said.

“It’s a little bit later than we were hoping for,” he said.

The poles the lights will go on are on order, but a little later than expected, pushing off their arrival, Gorneau said in a phone interview Friday. The delay in the poles’ order was due to a design change, he said.

The whole project was supposed to be done June 23 or else the contractor, DDI Earthworks of Gorham, would be penalized. But the firm is getting added time, at no pay cut, due to the pole issue, Gorneau said.

The lights will be full traffic lights with amber, green and red, MDOT staff said. But it’s likely that, given the new time frame for the installation, they’ll first be programmed as flashing lights, MDOT regional planner Gerry Audibert said.

That will give motorists a chance to get used to the lights being there, and will avoid introducing the lights’ other settings during the peak traffic months of July and August, Audibert said in a phone interview Monday.

The setup through the end of August will likely be yellow flashing lights for both northbound and southbound Route 1, and a red flashing light for those entering Route 1 from Route 27, Audibert said.

Work is under way Monday through Friday, Gorneau said. The weather has cooperated, he said.

The sidewalk part of the project has been progressing well; however, the gravel failed an MDOT check, Gorneau said. MDOT found too high a percentage of the fines, or smallest pieces, so the contractor will need to replace it, he said.

The sidewalks should still be done well ahead of the project’s due date, Gorneau added.

Together, the sidewalks, crosswalks and traffic lights are a $389,000 project, Gorneau said. He expects it to improve safety, most notably for Route 1 traffic turning left onto Route 27, Route 27 traffic turning left onto Route 1, and for pedestrians. “I think it’ll make a big difference,” he said.