The City Council may at any time after the adoption of this Charter establish and maintain a City Planning Board, or act as the planning board, and have such powers and duties as the Council may prescribe relative to city planning and accordance with state law. The Council by duly enacted ordinance may determine the number of board members. If a board is appointed, one of the planning board members shall be the Mayor and another member shall be a member of the council designated by the Council upon recommendation by the Mayor. Each member appointed shall be appointed for a four year term. Any vacancy in and during the unexpired term of an appointed member shall be filled by the council upon recommendation by the mayor. The City Administrator shall provide the Planning Board with the necessary clerical help, office equipment, and supplies.