Section 6(2)(vii) in The Chennai Metropolitan Water Supply and Sewerage Act, 1978
(vii)to prescribe the manner of treatment of trade effluents before discharge thereof and to regulate the discharge thereof into any sewer canal, river or other water channel utilised for the purpose of 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;