If the board of aldermen or the selectmen deem public convenience and necessity require the railroad to be constructed in part longitudinally upon a public way or place, they may, in granting or agreeing to a location thereon, prescribe how the tracks shall be laid, the kind of wires, poles, rails and other appliances which shall be used, and may impose such terms, conditions and obligations incidental to and not inconsistent with the objects of a street railway company as the public interests may require, and the department approves.
Massachusetts Legal Code