The Municipality shall, either on its own or through any other agency,

construct and maintain drains and sewers, and provide a safe and sufficient Municipality to outfall, in or outside the municipal area, for effectual drainage and proper provide drainage, discharge of storm- water and sewage of the municipal area in such manner as sewerage and may not cause any nuisance, whether by flooding any part of the municipal outfall. area, or of the areas surrounding the outfall, or in any other way: Provided that no place, which has not been used before the commencement of this Act for any of the purposes specified in this section, shall be so used except- i. in conformity with the provisions of any State law relating to land use planning or any other law relating thereto for the time being in force or ii. with the approval of the State government, in the absence of any such law: Provided further that with effect from such dare as may be appointed by the State Government in this behalf, no sewage shall be discharged into any watercourse until it has been so treated as not to affect prejudicially the purity and the quality of the water of such water course.