Section 15. The commissioner shall establish a watershed system advisory committee to advise the division on its policies and regulations regarding fishing, boating, and recreational activities and other environmental and wildlife matters in all of the watershed system areas under the control of the division, exclusive of the Quabbin watershed and the Ware river watershed. The committee shall consist of 9 members, the qualifications of whom shall be determined by regulation by the commissioner. The committee shall elect a chairperson from among its members, shall meet at least twice each calendar year, and may provide for alternate members to participate fully in its meetings whenever a regular member is unable to do so.