Wednesday will mark the beginning of a construction project that will snarl traffic on a major thoroughfare in Maine’s largest city throughout the summer.

A contractor hired by the city of Portland will begin separating sewer and stormwater systems from Back Cove and up along State Street. The work will also include upgrades to pedestrian crossings on State Street from Park Avenue to Cumberland Avenue.

For two months, beginning in August, State Street will be closed off, with only local residents being able to use it. On-street parking in the construction areas will also be affected. But trash and recycling collection will proceed as normal.

The project will have a significant impact on the average of more than 12,500 vehicles daily that use State Street, which funnels drivers getting off Interstate 295 to South Portland and Cape Elizabeth.

“It will be a nightmare to travel through there, so I apologize in advance,” City Manager Jon Jennings said in March, when the City Council approved the project.

City Councilor Spencer Thibodeau, who represents the Parkside neighborhood and leads the council’s transportation committee, said he will be working with the city manager on sign placements to help people navigate the construction zone without adversely affecting the neighborhood. He hopes that can be accomplished by directing traffic to the Fore River Parkway or Franklin Street.

“I’ve told each neighborhood association that would be impacted the most that this is … going to be a really disruptive process,” Thibodeau said.

Sargent Corp. will begin by installing a new stormwater outfall into Back Cove, according to the city. That work, which will affect the park area near the Back Cove parking lot, will last for about three weeks, before work begins on the Preble Street Extension. The extension will be closed nightly, from 7 p.m. to 7 a.m., for about three weeks, beginning around July 24, to allow crews to install a new drain.

Crews will begin digging up State Street on July 17, beginning at State Street Extension, which runs through Deering Oaks.

The extension will be closed nightly, from 7 p.m. to 7 a.m. for about two months, so new sewer and storm drains can be installed. Also, a new sidewalk and pedestrian improvements are scheduled from the athletic fields to the pond.

Work on State Street, from Park Avenue to Cumberland Avenue, is scheduled to begin Aug. 10, the city said.

In addition to sewer and stormwater drains, the project will also include new water and gas mains, as well as new pavement and new sidewalk ramps that comply with the Americans With Disabilities Act.

“Local residents on State Street will be able to access their driveways during this time,” the city said.

Trash and recycling pickup will continue, though pickup times may vary. The city encourages residents to place their items on the curb by 6 a.m.

The City Council reallocated nearly $410,000 in federal money in March to help fund the pedestrian safety portions of the project. Those Community Development Block Grants originally had been earmarked for improvements along Marginal Way being coordinated with the so-called “midtown” development.

But the midtown development, approved more than two years ago for 445 apartments in three six-story buildings with first-floor retail, along with an 800-vehicle parking garage, has shown no signs of moving forward anytime soon and the city could lose the federal funding if it is not spent by the end of the year.

“If the Marginal Way project … is not reallocated to the State Street project, Portland may be in jeopardy of not meeting its timeliness deadline,” city planners said in a March 6 memo to the council.

It was not clear what the entire State Street project will cost, as City Hall was closed Monday.

Randy Billings can be contacted at 791-6346 or at:

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