Section 232A(3) in The Mumbai Municipal Corporation Act, 1888
(3)The owners for the time being of the several premises constituting a group or block drained under sub-section (1) shall be the joint owners of every drain, constructed, erected or fixed, or continued, for the special use and benefit only of such premises, and shall, in the proportions in which it is determined that the owners of such premises, are to contribute to the expenses incurred by the Commissioner under sub-section (1), be responsible for the expense of maintaining every such drain in good repair and efficient condition, but every such drain shall from time to time be flushed, cleansed and emptied by the Commissioner at the charge of the municipal fund.]