Section 261(a) in The Mumbai Municipal Corporation Act, 1888
(a)construct and maintain water works, either within or without [Brihan Mumbai] [These words were substituted for the words 'Greater Bombay' by Maharashtra 25 of 1996, (w.e.f. 4.9.1996).] and do any other necessary acts;(aa)"construct and maintain tunnels and undertake other related works, as part of the municipal water works, below any land, in whomsoever such land may vest for carrying water;] [Clause (aa) was inserted by Maharashtra 37 of 1981, Section 8.]