Experts weigh in on making city flood proof

NT Correspondent

Bengaluru: To answer questions such as – How do we fix rain - relate d problems and prevent further issues in our homes, apartment complexes and layouts? Is your neighbourhood at risk? Do you suspect some of the properties have encroached buffer zones? Are there poorly designed drains that overflow easily? Citizen Matters, a civic media platform recently held a ‘Bengaluru Citizen Clinic’ to address the issue of flood-proofing homes and neighbourhoods.

Basement flooding

To the question of basement flooding, Vishwanath Srikantiah, a water expert, said the phenomenon responsible for this is called groundwater flooding. “The ground water table has risen in many areas leading to flooding. At an individual scale one can try digging a well and use the water. They must also prevent surface water from entering their premises while pumping the rest out.”

White topping to blame?

On how road designs affect flooding in neighbourhoods, Dr Anjali Karol Mohan, an urbanist explained how she has noticed issues of flooding especially in areas that have white topped roads. “The level of the road has gone above the level of the houses, especially in the older parts of the city which would never be flooded,” she said.

Ideally, the contractors responsible must strip the roads of the material laid out previously and then go ahead with their asphalting work. However, this does not happen, altering the levels of the road, pavements and houses. “Earlier, we could notice this only in marginalised settlements, but now they can be rampantly found across the city,” she elaborated.

As a temporary solution, she suggested residents put up a four inch barrier outside their house to curb the flood water from entering. Talking about longterm solutions she said, “It is a dialogue that must be had with the government and mobilisation needs to be done to make sure contractors follow their clauses strictly.”

Concrete spread

To a citizen’s question on whether there exists a rule on concretisation of large plots such as schools, spaces of religious significance and government institutions, Dr Anjali said, “These large campuses have massive amounts of pervious surface. A solution we are putting forward to the government is to map these spaces in neighbourhoods.

While there is a rule that only a certain percentage of the area can be concretised, it is a matter of enforcement by them.” The campuses have large plots of un-concertised land, which will facilitate in allowing the excess rain water to seep through the ground and in turn recharge the groundwater table.

Sewage in lakes

Talking about entry of sewage into lakes, Captain Santhosh Kumar, a lake activist said, “It is a common problem across Bengaluru. It is due to irresponsible urban development.” He added that the rajakaluves (storm water drains) and sewage drains have now become synonymous and are not being treated as different entities.

“The rajakaluves are responsible for taking the rain water into lakes while the sewage drains divert the sewage to treatment plants. Segregation is the key and needs to be addressed before our lakes turn into poison ponds,” he urged for action.