Mass. Gen. Laws ch. 92 § 33
The division of state parks and recreation, hereinafter referred to as the division, may maintain and make available to the inhabitants of Arlington, Belmont, Boston, Braintree, Brookline, Cambridge, Canton, Chelsea, Dedham, Dover, Everett, Hingham, Hull, Lynn, Malden, Medford, Melrose, Milton, Nahant, Needham, Newton, Quincy, Revere, Saugus, Somerville, Stoneham, Swampscott, Wakefield, Waltham, Watertown, Wellesley, Weston, Westwood, Weymouth, Winchester and Winthrop, which shall constitute the urban parks district, open spaces for exercise and recreation, in this chapter called reservations and, for the purposes set forth in this section, the powers of the division shall extend to, and be exercised in, said district.
The division may preserve, beautify and care for such public reservations, and also, in its discretion and upon such terms as it may approve, such other open spaces within said districts as may be intrusted, given or devised to the commonwealth for the general purposes of this section or for any one or more of such purposes as the donor may designate.
The division may, for the purpose of making the rivers and ponds within said district more available as open spaces for recreation and exercise, regulate the use of certain spaces along or near said rivers and ponds, and care for and maintain spaces so regulated, and plant, care for, maintain or remove trees, shrubs and growth of any kind within said regulated spaces.
The commissioner of conservation and recreation, hereinafter referred to as the commissioner, may enter into and issue agreements, licenses and permits for recreational and other uses which he deems compatible and consistent with this section and Article XCVII of the amendments to the Constitution, provided, however, that such agreements, licenses and permits shall be for periods not exceeding 10 years, and shall be in writing.
This section shall not limit existing rights of any town in relation to water supply purposes or in any way obstruct its taking advantage of such rights.
Mass. Gen. Laws ch. 92, § 33