But for the Tehri dam, more areas in Hardwar would have been inundated. large dams help regulate flood flows and mitigate devastation

The unprecedented floods in Uttarakhand that wreaked havoc and left death and destruction in their wake, has brought to the fore the issue of vulnerability of the system and a lack of preparedness to face the situation in the face of natural disasters. The situation was compounded by the large influx of devotees and tourists to the area during the pilgrim season.

Questions are being raised on whether the tragedy was the outcome of unavoidable natural causes or man-made, which could have been prevented by taking timely measures. According to climatology experts, increasing global warming and extreme weather conditions resulted in intense rainfall and flash floods in the region. It’s a phenomenon that is likely to become more frequent in view of the fragile environment conditions. Scientists at the National Institute of Oceanography opine that due to a dearth of low pressure systems in the western Pacific Ocean, convective activity in Bay of Bengal and Indian Ocean brought rain-bearing winds towards the subcontinent, thereby, advancing the monsoon a month ahead of the usual, resulting in copious rainfall. The fast-melting snow in the Himalayan terrain simply added to the deluge.

Most environmental experts see the Uttarakhand tragedy as a man-made disaster, given that a natural disaster is one triggered by an earthquake or a cyclone. They cite unplanned development, rampant construction in the hills and illegal encroachments along the rivers as a reason for the catastrophe. Himalayan hills being ecologically fragile, the wanton destruction of the hills by blasting and tunnelling activities was a calamity waiting to happen.

Meanwhile, self-appointed anti-dam activists have also jumped into the fray to flaunt their favourite, unproved theories that the hydroprojects, constructed and under construction, on the rivers triggered the floods and devastation.

Hydro-experts point out that landslides and floods wiping out settlements were there even two centuries back when construction activities were negligible. Encroachments and haphazard dumping of debris is what has contributed to the huge damage now. As to the failure of dams in minimising the flood damages, they stress that these projects are not designed to regulate large floods which only major dams would be able to do.

It has been claimed that the much-criticised Tehri dam has the capacity to absorb and regulate the unprecedented flow of flood waters, touching 2.5 lakh cubic feet per second in the Bhagirathi and its tributaries. Only less than seven per cent of the flow was released downstream, thereby, minimising the damages. But for this dam, more areas in Hardwar and Rishikesh would have been inundated. It is clear then that both natural and man-made factors were responsible for this worst-ever disaster.

There are lessons to be learnt from the calamity and remedial actions taken expeditiously to reconstruct and repair the damage. These include strict implementation of flood plain zoning rules, zero-tolerance for encroachments in the hills and flood plains and an end to illegal construction and mining activities. Rising flood levels and swollen rivers are causing immense damage in other parts of the country too, as there are no major dams to regulate their flows. To cite a few: The flooded Brahmaputra in the North-East, the Ganges in the eastern parts and the Godavari down south are inundating many villages and rendering thousands homeless.

As demonstrated by the Tehri dam, large dams are not just a bulwark against the angry floodwaters, they help regulate the flood flows and mitigate the sufferings of the affected people. Similarly, projects like inter-linking the rivers to divert flood flows to water deficit areas would also be a step in the right direction. 

Hopefully, the Uttarakhand disaster will push the authorities to strictly implement flood plain regulations and actuate major projects in public interest, and ignore voices against big-dam projects. There is an urgent need to help the country to get rid of the ‘flood-drought syndrome', instead of relying on short-term measures that only cater to the vested interests of a few.

(The writer is a former Member Secretary of Indian National Committee on Irrigation & Drainage, Ministry of Water Resources)