WINDHAM - A 4.1-mile stretch of an old railroad bed soon could become a trail for bicyclists, walkers, runners and even parents with baby strollers.

The state Department of Transportation and the Department of Recreation and Economic Development have agreed to let the town improve the old railroad bed, known as the Rockingham Recreational Trail, as part of a proposed Salem-to-Concord bicycle and pedestrian trail.

Plans to upgrade the local trail will require the approval of the selectmen, who are scheduled to discuss the proposal May 9.

The trail still is used by snowmobiles in the winter.

If the Windham board approves the project, a group of local residents, called the Windham Rail Trail Alliance, will raise the money to cover the cost of the improvements and will oversee the work to upgrade the trail, Selectwoman Margaret Crisler said. No taxpayer money will go toward the work, she said.

The section of the trail in line for the improvements is between the area of Routes 111 and 28 in Salem and North Lowell Road in Windham. The proposal involves improving this section of the trail for bicycles, pedestrians and horseback riders as well as for snowmobilers and cross-country skiers in the winter. The options under consideration include paving the trail with stone dust shoulders or using an unpaved hard pack with the same type of shoulders.

Two years ago, the state formed an advisory committee to study options for developing a path along the Interstate 93 corridor. The panel recommended using abandoned railroad beds, and part of a state heritage trail, to serve as the path's foundation.