Lake (g)razed to ground

Lake (g)razed to ground
DEEPTHI M R


Bangalore’s growth can be summed up in two ways. One, a super-fast growth and two (a dubious one, though), its vanishing water bodies. Take, for instance, the Nagarbhavi lake, which prided itself for its aquatic life and rare avian population. Now, it is almost invisible.
A vast stretch of water weeds has converted the lake bed into a grazing land. Located on a four-acre area, it was once home to several species of birds, but has now turned into a marsh filled with hyacinth and weeds.
Till recently, people used to flock to the lake to recharge their lungs with fresh air or for religious rituals.
SEWAGE THE CULPRIT
“The disappearing lakes has got to do with sewage water getting mixed with lake water. With excess amount of nitrates and phosphates, sewage water is nothing but a fertile feed for the growth of aquatic weeds. When this is let into the lake either due to the encroachment of sewage canals or illegally, it will foster the growth of weeds and shrink the water-holding capacity of the tank,” said Dr Ramachandra Mohan, professor, zoology department, Bangalore University.
Experts have said the increased growth of water hyacinth and grass will drive lakes towards the path of extinction. “When water plants grow in the lake, water gets more oxygen. But an excess amount of these weeds destroy the lake. Further, weeds consume all the oxygen available in the water and restrict sunlight from entering the lake. This spurs the growth of bacteria,” Dr Mohan said.
FOUL SMELL
Sampath Kumar, a resident of the area, said the accumulated silt and decaying weeds besides the sewage water emit foul smell.
A portion of the lake was given to Ambedkar Polytechnic College located right behind the lake. A dhobi ghat is situated behind the lake and washermen use this water for washing clothes. “The water is contaminated as the sewage water from the college hostel is let into the lake and the same water is used by washermen at the dhobi ghat. The lake has shrunk in size in the past 12 years,” said Hemavathi, another resident.
The Karnataka State Pollution Control Board (KSPCB) officials had visited the spot in 2006 and asked the people in the locality not to come up with new buildings close to the tank bed. Since then, nothing has been done to preserve this precious water body.