It is 10 years now since a citizens’ initiative to
rejuvenate water bodies began in the city. Eight tanks in the city and
another in the periphery were desilted. So were the canals that brought
water to these tanks. The efforts proved to be good in 2004 when a good
monsoon filled up the tanks.

But, 10 years down the
line – after Siruthuli’s launch in 2003 – the tanks and canals present a
sordid sight: some are bone dry while the others hold more of sewage.

All
along, the desilting and removal of hyacinth has gone on without being
complemented by the necessary infrastructure for sewage treatment. In
fact, the tanks that hold water now pose greater threat than those that
are dry, because the sewage only contaminates groundwater. Two major
canals – Sanganur Canal and the Karuparayan Canal (near Vadavalli) – are
filled with sewage. Heavy rain will flush the sewage into a couple of
tanks. But, throughout the year small rivulets of sewage empty into
Valankulam, Big Tank, Muthanankulam, Kurichi Tank, Krishnampathy Tank,
Selvachinthamani Tank and Selvampathy Tank.

Unauthorised
tenements with poor sanitation have come up around the tanks and the
sewage from these areas finds its way into the water bodies.

Siruthuli’s
Managing Trustee Vanita Mohan says the organisation has done a study of
the ground water quality in all the 100 wards of the city and has come
up with results that reveal heavy groundwater pollution. If this
situation were to continue for long, the city’s groundwater will be
rendered totally unusable. The study findings will be released on Friday
as part of the World Water Day observance.

The
present situation points out that unless the city has a comprehensive
underground drainage system and sewage treatment facility, the purpose
of rejuvenating tanks will be defeated by discharge of untreated sewage.

The
Coimbatore Corporation has drawn up a Rs. 130 crore rejuvenation
programme under the Jawaharlal Nehru National Urban Renewal Mission.
But, its drainage and sewage treatment projects under the same mission
will have to be in place first.

At present, the tanks that do have water are covered with hyacinth. And, the hyacinth feeds only on sewage.

Over
the last 10 years, rainwater harvesting structures across the city too
have helped in recharging the aquifers. At many places, the static level
of groundwater has risen from 200 ft to 60 ft. But, the sewage in the
tanks percolates and contaminates groundwater, defeating the very
purpose of recharging the aquifers, Ms. Mohan points out.

Siruthuli’s
progress seems to have been hampered by lack of sustainability. “We
have the plan and expertise, but there is no go ahead from the
Government department concerned. The Kurichi Tank is dry and this is the
right time to desilt the tank and prepare it to hold more water during
monsoon. Besides, the discharge of untreated sewage must also be
prevented,” says Ms. Mohan.

Details of study of the
tanks show that their water-holding capacity has shrunk because of
silting and encroachments. Adding further agony is the sewage.