Section 82(3) in Assam Notified Urban Areas (Other than Guwahati) Building Rules, 2014
(3)In addition, every Group Housing Scheme, Apartment or commercial complexes and Institutional buildings etc. shall be provided with required facilities and infrastructure for conservation and harvesting of rain water, namely:-(a)Percolation Pits:- The paved surface around the building shall have percolation pits of 1.2m x 1.2m x 1.2m covering at least 30% of such area. Such pits shall be filled with small pebbles or brick jelly or river sand and covered with perforated concrete slabs;(b)Terrace water collection:- The terrace shall be connected to a sump or the well through a filtering tank by PVC pipe. A valve system shall be incorporated to enable the first part of the rain water collected to be discharged out to the soil if it is dirty;The filtering tank measuring 0.6 m to 1.2 m square can be constructed near the sump. A tank can be divided by a perforated slab and one part shall be filled by small pebbles and other by brick jelly. The bottom portion of the tank shall have slope to avoid stagnation of water;(c)Open Ground:- Whenever there is open ground a portion of top soil shall be removed and replaced with river sand to allow slow percolation of rain water.(d)Piped recharged
