BWSSB requirements
(RCC precast ring well) of minimum 20 liters per square meter of roof area and a minimum of 10 liters per square meter of paved open space provision shell be made. The open well / recharge well of depth of 3 meter (minimum) and diameter of .9 meter (minimum) with out filling in the well (like aggregates, jelly, sand etc.) provision shell be made. You may store rainwater in a tank / sump or recharge rainwater in to the ground through a well or you can use a combination of these two to achieve the stipulated capacity of ‘X’ liter. Where X = roof area in sqm x 20 + paved open area in sqm x10. The open well should be of minimum 3 ft diameter and 10 feet deep. Source: pdf
- In the worst case, where they say “you’ve used sump for kAverI water, can’t use it for rainwater storage” and say terrace covers enter entire 1200sqft, we would need to show 2229.67 liters capacity in well, which requires
Implementations
- Water harvesting in Vijayanagara- shivakumar of IISc does not use BBMP water connection (check YouTube) - says 2 good rains suffice.
- 2013 saurabha slides.
Calculations
- From http://rwh-advisor.info/
- Inputs: Roof area 820 sqft, daily consumption 135 liters per person day. For Bengaluru_North the annual rainfall is 833 mm / 33 inches
- Suggested Tank Capacity - 3,000 ltrs.