Despite taking the initiative to propagate rainwater harvesting (rwh) as a household concept, Chennai has surprisingly been losing its capacity to hold water over the years. This incongruity could be attributed to the message not percolating down convincingly enough to the city's domestic consumers (a survey suggests that though 48 per cent have evinced interest, only two per cent have actually taken to it). The state assembly recently decided to amend the Chennai Groundwater Act of 1987 in the wake of this abysmally low implementation rate. The law will, among other changes, make it mandatory for all new as well as existing buildings of the metropolis to install rwh structures.

The authorities have taken recourse to such stringent measures to overcome a peculiarity that Chennai faces