(1)Other things, being equal, but subject to the provisions of the Punjab Water Supply and Sewerage Board Act, 1976 (Punjab Act 28 of 1976), the Municipality shall construct and maintain drains and sewers and provide a safe and sufficient out-fall, in or outside the municipal area of the Municipality, for effectual drainage and proper discharge of storm-water and sewerage of the municipal area in such manner, as not to cause any nuisance whether by flooding any part of the municipal area of the country surrounding the out-fall or in any other way :Provided that no place which has not before the commencement of this Act been used for any of the purposes, specified in this section, shall be used except in conformity with the provisions of the Punjab Water Supply and Sewerage Board Act, 1976 (Punjab Act 28 of 1976) :Provided further that on and after such date, as may be appointed by the Government in this behalf, no sewage shall be discharged into any water- course, until it has been so treated as not to affect prejudicially the purity and quality of the water into which it is discharged.