Despite the publicity that it receives in the media and the growing number of people who have adopted it, rainwater harvesting remains out of the consciousness of most people in semi-arid Chennai.
RWH is a well-recognised acronym these days, and one of its many uses is to store enough water for gardening in a city with prolonged drought spells.
I installed rainwater harvesting structures in my apartment complex in Rangarajapuram, Kodambakkam much before the concept became a dire need and certainly long before the Government stepped in with its diktat that it should be in place in all buildings by a given date in 2003.
.One of the components of the system in my apartment building, is the tapping of rooftop run-off using a high density polyethylene tank.
The 150 litre tank harvests the water run-off from the roof of a motor room, and there is a provision for overflow into a percolation system from the tank.
A plastic tap fitted to the base of the tank helps draw the rainwater, which is useful for gardening for several days at a time. Due care has to be exercised in this operation, as the water could be contaminated by animal urine, faeces and other atmospheric impurities as it is directly harvested from the roof, in the open.
I will shortly feature a photo of the system here. The water is used to grow a variety of potted plants, including flowering species such as Hibiscus and Ixora. An operation to germinate seeds for propagation is also being pursued.
The best thing about rainwater is that it has very low total dissolved solids, and is ideally suited for gardening. I couple this with my intense dislike for chemical fertilisers and pesticides, all of which makes my operation a completely organic gardening venture.