(a) Each member of a regional board shall be appointed for a term of four years. Vacancies shall be immediately filled by the Governor for the unexpired portion of the terms in which they occur.
(b) The term of office for members of each regional board shall be staggered and shall expire in accordance with the following schedule:
(1) Two members on September 30, 2013, and every four years thereafter.
(2) Two members on September 30, 2014, and every four years thereafter.
(3) Two members on September 30, 2015, and every four years thereafter.
(4) One member on September 30, 2016, and every four years thereafter.