Mumbai flood map template to tackle urban deluge

Shiv Kumar

Tribune News Service

Mumbai, December 13

The devastating flood that inundated Chennai may have been prevented had the authorities heeded warnings issued 10 years ago to map flood-prone areas in the country.

The demand for flood mapping was first made after record rainfall flooded Mumbai on July 26, 2005. Recommendations made by the Madhav Chitale committee to map flood-prone areas in Mumbai and other cities were lost in bureaucratic red-tape.

“At the moment, there is no hazard mapping in the country. Cities are not consciously generating data on flooding,” says Anumita Roychowdhury, Executive Director-Research and Advocacy, Centre for Research and Environment, New Delhi.

However, a handful of private initiatives provide a ray of hope to residents of cities who fear the wrath of water suddenly unleashed on them. The insurance industry has emerged as one of the biggest supporters of hazard mapping in the country after the spate of floods cost insurers tens of thousands of rupees in losses.

According to insurance industry sources, losses from the recent floods in Chennai alone would come to Rs 2,000 crore. “The losses suffered by the insurance industry alone would come to Rs 1,500-Rs 2,000 crore since most of the private homes and small businesses are not insured or are under-insured,” an official of the New India Assurance Company said. The auto industry is expected to make major claims for disruption of business, officials said.

The National Insurance Academy (NIA), Pune, has now undertaken a pilot project to start the process of preparing flood hazard mapping across the country. The first step will see the mapping of the Damanganga river flowing through Maharashtra and Gujarat. The river’s basin is 131 km long and the hazard map will span both sides of the river covering both urban and rural areas.

NIA officials say the map would be based on Geographical Information System and would attempt to identify locations vulnerable to various hazards.

A computer-aided scenario would attempt to estimate damages likely to be caused by floods and other hazards that need to be covered by insurance. “Depending on the study, insurance companies will attempt to value risks posed to buildings and infrastructure from floods and other hazards and accordingly charge premia on insurance policies,” says Abhishek Sanghvi, an analyst with a Mumbai brokerage.

The Indian Institute of Technology, Powai, is also working on a project to map the flood risk posed to Mumbai. It has tied up with Monash Research Academy to “assess and map the spatial-temporal pattern of hydrologic, hydraulic, socio-economic and infrastructural elements that contribute to flood risk and vulnerability for Mumbai”.

According to the project proposal put out by IIT, a colour-coded map of Mumbai will show the flood risk across the city under the categories: very low, low, medium, high and very high.

Meanwhile, the Union Ministry of Environment and Forests has slowly begun to move towards assessing flood peril for the entire country. Under a proposal by the Ministry of Environment and Forests (MoEF), state governments will be required to create hazard maps of cities as part of efforts to generate data on flood risks.