he authorities not taking pre-emptive steps against water stagnation in Bangalore?

he authorities not taking pre-emptive steps against water stagnation in Bangalore?
— Photo: K. Murali Kumar

Water woes: With most of the lake beds in the city being encroached upon flooding of roads is a common sight. A scene at Hosur Road during the recent rain.
BANGALORE: At Puttenahalli, a man accompanies his brother, wading through stagnant water of three days with a bucket of fresh water so that his sibling can wash his feet at a dry place and go to work without smelling.

Areas are flooded in J.P. Nagar and the instant solution is to dig up a road to convert it to a drain, and never mind that the residents have to go without power for three whole days.

An important link road at Bhadrappa Layout is closed and pedestrians are forced to negotiate over the treacherous parapet of a bridge, where one wrong step could land them right into the drain.

After the deluge in 2005, it probably would not have been too much to expect that flooding such as last weekend’s do not recur, at least as often.

So why does Bangalore take a beating every time it pours? Have the administrators started to look at long-term solutions or are they merely adapting? Public Eye explores possible solutions to mitigate rain misery.

Pretty pavements
With an increase in impervious surfaces such as roads and pavements, rain water finds no way to seep into the ground. “A gradual fall in vegetation and natural surfaces has meant there are no sinks to absorb the rain. Chances of flash floods increase,” says T.V. Ramachandra from Centre for Ecological Sciences at the Indian Institute of Science.

Granite slabs on pavements are being replaced with interlocking tiles, as part of beautifying the city. “These surfaces are feasible in countries abroad because they do not receive as much rain as we do. We need pavements that allow for water to seep in and not interlocking tiles that rainwater merely runs over,” says Meera Baindur, an environment researcher.

Drains
Overflowing drains have always been held up as the main culprit for flooding in the city. Tertiary drains carry runoff water from residential areas to secondary ones. These are then linked to primary storm water drains that carry the runoff to lakes.

“In many areas, we found that the tertiary drainage system was completely absent,” says Raja Rao, who led the expert committee constituted by the Karnataka High Court to look into the state of roads in Bangalore. Only if we evolve an effective system to carry run off water from localities can we control flooding to a large extent, he says.

Critical about the way drains are laid, Capt. Rao said the current method is to lay a uniform-sized drain along the road. “But the drain size must be augmented as it goes along because the amount of water that flows into it increases.” For clogged drains, the committee had recommended that mechanical screens be installed to permit free flow of water.

Preserving lake ecology
With lakes being the final destination for storm water drains, preserving water bodies assumes more significance. Even so, there continue to be more instances of lake beds being encroached than of restoration of lakes. There are even fewer attempts to restore the now degraded links between the lakes.

“We simply must link our lakes again. Otherwise, the ones remaining will turn into water bowls that dry up when there is no rainfall. Eventually they will lose their water-holding capacity completely and rain water will have to find its way to low-lying areas,” says Prof. Ramachandra.

Consider this: J.P. Nagar and areas around are flooded constantly because the large amount of weeds covering Puttenahalli Lake has diminished its water-holding capacity. Majestic and surrounding areas are under water because the Kempegowda bus stand has been built on Dharmanbudhi Tank. Madivala, Arakere, Hulimavu, Begur, Puttenahalli, Sarakki and Lalbagh lakes overflow into surrounding residential layouts because the links between them have been broken.

With the city at a crucial juncture of its development, the huge investments in its infrastructure could come to naught if severe action is not taken against authorities who have been blatantly allowing encroachments and ecological parameters are ignored while chalking out long-term solutions.