NARRAGANSETT — A long-awaited extension of the South County bike path from Wakefield into Narragansett is about to get back on track and could be finished within a year, state and local officials say.

Delayed by a land swap and questions about who owned a portion of the proposed route, the extension is tentatively scheduled for construction next spring, said Robert Smith, acting chief of design at the state Department of Transportation.

Expected to cost about $750,000, the project will extend the existing path by about eight-tenths of a mile, from Route 108 in Wakefield to Mumford Road in Narragansett. To get there, the path will pass under Route 1 through an old train tunnel.

Smith said the plans are nearly complete and will soon be taken up by the Coastal Resources Management Council.

“It’s been a long wait,” he said.

Laura Ricketson, a coastal council spokeswoman, said there is a question as to whether the council or the state Department of Environmental Management will have jurisdiction over the project. But she called the application “pretty standard,” based on information the DOT had filed with the council.

The questions about ownership involved a 1.46-acre parcel that the town obtained from the U.S. Fish & Wildlife Service in exchange for 15.43 acres, mostly wetlands, at the north end of the Canonchet Farm property. Some of the property lines on the acquired property were disputed, so the proposed route has been moved away from those areas, Smith said.

With the problem resolved, Smith and Town Manager Jeffry Ceasrine were hopeful that the project will get the needed approvals and be finished “sooner than” next fall, as Ceasrine put it at last week’s Town Council meeting.

The existing 5.6-mile path, formally known as the William C. O’Neill Bike Path, runs from Kingston Station, in South Kingstown, down through Peace Dale and into Wakefield. O’Neill pushed for bike paths around the state while serving as a state senator and representative. He died in 2003.

redgar@projo.com