Massachusetts General Laws Part III. Courts, Judicial Officers and Proceedings in Civil Cases (Ch. 211-262) Ch. 253, § 50A

The department of environmental management shall, subject to the appropriation of funds for such purpose, erect signs in the vicinity of all roll dams owned or under the control of the commonwealth or any of its political subdivisions to warn boaters of the location of said dams. For the purposes of this section a roll dam shall mean any broad crested weir, sharp crested weir or design head weir, the purpose of which is to change the flow of rivers from a critical to a noncritical flow.

Failure to comply with the provisions of this section shall not be used as evidence in any action commenced under the provisions of chapter two hundred and fifty-eight.