102. Rainwater storage Arrangements

(1) Unless otherwise stipulated specifically in a Town Planning Scheme, workable rainwater storage arrangements shall be provided as an integral part of all new building constructions through the collection of rooftop rainwater for the following occupancies, namely:-

1. Group A1---- Residential (In the case of single family residential buildings , if the total floor area of the building is upto 150 sq.metres and if the plot area is upto 320 sq.metres, the rainwater storage arrangements are not mandatory.)
2. Group A2---  Lodging Houses
3. Group B---  Educational
4. Group C---  Medical/Hospital
5. Group D --- Assembly
6. Group E----  Office/Business
7. Group F----  Mercantile/Commercial (If the total floor area of the building is upto 100 sq.metres and if the plot area is upto 200 sq.metres, the rainwater storage arrangements are not mandatory.)
8. Group G1 and Group G2 ---- Industrial (only for workshops, assembly plants, laboratories, dry cleaning plants, power plants, Gas plants, refineries, diaries, food processing units and any other occupancies notified by the Government from time to time).
9. Group I (1)----  Hazardous (Automobile wash stall, Automobile Service Stations, Service Garages with repairing facilities and any other occupancies notified by the Government from time to time):

 Provided also that, the rainwater storage arrangements are not mandatory for thatched building.
(2) The components of a workable rainwater storage arrangement as stipulated in sub rule (1) above, shall include:

1. Roof gutters;
2. Down pipe and first flush pipe arrangement;
3. Filter unit; and
4. Storage tank with provisions for drawing water and spill-over.

(3) The minimum capacity of the storage tank as stipulated in sub rule (2) (iv)of the rainwater storage arrangement shall be at the rate give below:

• Group A1 --25 litres/sq.m.of floor area
• Group A2 --25 litres/sq.m.of floor area
• Group B --50 litres/sq.m.of floor area
• Group C --50 litres/sq.m.of floor area
• Group D --50 litres/sq.m.of floor area
• Group E --50 litres/sq.m of floor area
• Group F --25 litres/sq.m of floor area
• Group G1and Group G2 --50 litres/sq.m.of floor area
• Group I(1) --25 litres/sq.m.of floor area

Provided that, the floor area to be considered shall be the total floor area in all floors.
(4) The owner(s) / occupier(s) shall maintain the rooftops and the rainwater storage arrangements in healthy working condition.
(5) Additional arrangements for carrying the spillover water from storage tank to recharge well or recharge pond or percolation pit need be provided only if both groundwater recharging arrangements and rain water storage arrangements are provided as laid out in this chapter.