Section 121(2) in West Bengal Municipal (Building) Rules, 2007
(2)The tank of high level for distribution of water in the premises shall be constructed of metal reinforced cement concrete or lined with metal or metal sheets and be of such a design, weight and quality as has been approved by the Authority. The tank or cisten at ground level or below ground level for receiving supply from the water mains is to be constructed in the wider side and/or the back space (leaving) 1.52 m for the back boundary line or within the built up area or partly between the side space, back space and the built up area. The depth of foundation of the tank shall not exceed 0.75 m (2'-6") from the ground level, the ground level being taken as 8 cm (0'-3") above the abutting footpath. This tank shall be water tight, properly covered over and shall be constructed of reinforced concrete or brick work in cement mortar or designed according to a manner approved by the Authority and shall be rendered inside with cement mortar.
