BANGALORE: The Bruhat Bangalore Mahanagara Palike (BBMP) is contemplating parks and playgrounds in low-lying areas to avert rain-induced calamities.
"No construction will be allowed in such places. Even if water gushes, there will be no calamities. Further, we will get more lung-space and greenery," said Chowdegowda, Additional Director (Town Planning), BBMP.
Unauthorised buildings that come up on stormwater drains add to the problem, said BBMP officials. "Black soil near the drains is very soft and not suitable for construction. These buildings look fine from outside, but the foundation is weak. Such buildings might collapse during heavy rains. We have been telling people not to construct buildings in these areas but they don't heed our words," Chowdegowda said.
He added the City Development Plan (CDP) 2015 would be revised keeping in mind 2031.
A N Yellappa Reddy, well-known environmentalist, believes the proposal is flawed. "If low-lying areas are converted into wetlands with aqua plants on either side, rain water can be naturally treated. The aquatic plants are capable of purifying water and recharging ground water," he said.
Reddy described the process as an "internationally proven mechanism". Even the Supreme Court has insisted on protection of wetlands. Once Bangalore had 3,000 lakes and 5,000 percolation tanks, and cultivation was common, providing wetlands. "These wetlands are capable of storing 100 times more water than rain water harvesting mechanisms," he explained.
"Low-lying areas should not be made into parks as water will flood them. But if wetlands are made, ground water levels will also increase," he said.
'Increase Building Height'
B R Niranjan, professor in the civil engineering department, University Visvesvaraya College of Engineering, and an expert in structural engineering, said, "When it rains, water levels rise up to four feet in low-lying areas. Water does not enter buildings if they are constructed five feet higher." "The width of the roads also needs to be increased to 30 feet. The low-lying areas in the city span just a few kilometres. Many buildings constructed there are unauthorised. If there is political will, they can be demolished in a phased manner and new buildings can be constructed by elevating the structure," he said.