Section 5(1)(d) in The Chennai Metropolitan Water Supply and Sewerage Act, 1978
(d)operating and maintaining the water supply and sewerage services in the [Chennai] [Substituted for the word 'Madras' by the City of Madras (Alteration of Name) Act, 1996 (Tamil Nadu Act 28 of 1996).] Metropolitan Area to the best advantage of the inhabitants of that area;