(4)The owners for the time being of the several premises constituting a group of 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 proportions in which it is determined that the owners of such premises are to contribute to the expenses incurred under sub-section (1), be responsible for the expenses of maintaining every such drain in good repair and efficient condition:Provided that every such drain shall from time to time be flushed, cleansed and emptied by the Chief Officer and the cost of such work maybe recovered from the owners concerned.
