(a) Any municipality may, by ordinance, designate its legislative body, except where the legislative body is the town meeting, or any existing board or commission, or create a new board or commission to be designated, as the water pollution control authority for such municipality. Any municipality located within the district of a regional water authority or regional sewer district established under an act of the General Assembly may designate such water authority or sewer district as the water pollution control authority for such municipality, with all of the powers set forth in this chapter for water pollution control authorities, provided such water authority or sewer district agrees to such designation. If a new board or commission is created, the municipality shall, by ordinance, determine the number of members thereof, their compensation, if any, whether such members shall be elected or appointed, the method of their appointment, if appointed, and removal and their terms of office, which shall be so arranged that not more than one-half of such terms shall expire within any one year. The water pollution control authority of the town within which there is a city or borough shall not exercise any power within such city or borough without the express consent of such city or borough, except that such consent shall not be required for any action taken to comply with a pollution abatement order issued by the Commissioner of Energy and Environmental Protection.

(b) Each municipal water pollution control authority designated in accordance with this section may prepare and periodically update a water pollution control plan for the municipality. Such plan shall designate and delineate the boundary of: (1) Areas served by any municipal sewerage system; (2) areas where municipal sewerage facilities are planned and the schedule of design and construction anticipated or proposed; (3) areas where sewers are to be avoided; (4) areas served by any community sewerage system not owned by a municipality; (5) areas to be served by any proposed community sewerage system not owned by a municipality; and (6) areas to be designated as decentralized wastewater management districts. Such plan may designate and delineate specific allocations of capacity to serve areas that are able to be developed for residential or mixed-use buildings containing four or more dwelling units. Such plan shall also describe the means by which municipal programs are being carried out to avoid community pollution problems and describe any programs wherein the local director of health manages subsurface sewage disposal systems. The authority shall file a copy of the plan and any periodic updates of such plan with the Commissioner of Energy and Environmental Protection and shall manage or ensure the effective supervision, management, control, operation and maintenance of any community sewerage system or decentralized wastewater management district not owned by a municipality.

(c) Any municipal sewer authority in existence prior to October 1, 1978, shall be deemed to be the water pollution control authority of such municipality unless the legislative body of the municipality, by ordinance, determines otherwise, and such water pollution control authority shall be deemed the successor to such sewer authority for all of the purposes of this chapter. All acts of any such sewer authorities from October 1, 1978, to June 1, 1979, are validated. The provisions of this subsection shall not apply to any action pending in any court or any right of appeal under this chapter existing on June 1, 1979.