The average groundwater level in the city has gone up by 0.2 metre since July. The level was 3.5 metre in June, senior officials of Chennai Metrowater said here recently and attributed the increase to the southwest monsoon.

They were speaking at the launch of a series of awareness meetings on rainwater harvesting structures and their maintenance, at the Metrowater area offices till September 17.

The launch function was held at the Area office II in Washermenpet. Each area office would hold meeting on an allocated day as part of the rainwater harnessing campaign.

Inaugurating the programme, Metrowater's Managing Director Shiv Das Meena said that earlier the city received major share of annual rainfall between October and December. This year, there seems to be a change in the pattern and southwest monsoon has been vigorous.

Besides reducing evaporation loss in the reservoirs, the rainfall has also helped in relatively less drawal from the waterbodies for the city supply. People must maintain their RWH structures round the year to reap benefits of the showers, he said.

M. Soundararajan, Metrowater's gydrogeologist, spoke on the importance of harnessing rainwater. Pointing out that nearly 60 per cent of the rainwater could be saved with proper RWH structures, he said their maintenance was a simple process and required only an hour. It involves cleaning of the terrace, drain pipe and filter materials.

Metrowater officials would provide free guidance over phone (28454080) or visit the locality in person.

Rain Centre's director Sekhar Raghavan said residents must check the soil profile to determine the depth of the RWH structure. Instead of recharge pit that is similar to a borewell, people must install recharge well, which is easy for maintenance.

He said it is sufficient to fill one-third of the filter chamber with materials. Several people opt to close the unused shallow wells. But, it can be converted into recharge wells.

Observing that most open spaces particularly in apartment complexes have been paved, Mr.Raghavan said besides rooftop water, the runoff water around the house could also be harnessed by putting a gutter near the entrance.

Pamphlets about rainwater harvesting and water conservation were distributed to the participants. Apart from clarifying their doubts, participants suggested various measures by which Metrowater could create awareness.