Monday, October 13, 2008

Weak flood defences in south Asia 'risking lives'

BBC: Recent flood events in Nepal, India and Bangladesh that displaced millions have stoked fears that defences along rivers in the region may not withstand climate change-induced floods, and could result in bigger catastrophes. Experts say many infrastructures are becoming weaker while the rivers' flows are getting stronger - a classic setting for projected climate change calamities.

Most floods this year were monsoon-related and many would argue they had nothing to do with changes in the climate. However, the Kosi disaster in eastern Nepal that left millions of Nepalese and Indians homeless was a different story altogether. The devastation was the result of human mistakes. The embankment along the Kosi was not properly maintained, resulting in it being overrun by the meandering river even when there was no flood.

The event has forced experts to imagine what could happen if rivers like the Kosi swell as the projected impacts of climate change take hold. "It is entirely possible that some of the existing structures could prove inadequate and possibly dangerous," said Rajendra Pachauri, head of the Intergovernmental Panel on Climate Change (IPCC). "They might not be able to withstand higher frequency and intensity of floods in the region," he told the BBC.

…The Kosi is one of the world's highest silt-yielding rivers. While the challenge silt-yielding rivers pose to dams and defences is yet to be properly dealt with, huge new river-taming infrastructures are in the pipeline….

Even though this shot is Walter Siegmund's dramatic image of the Stillaguamish River flood, thousands of miles from South Asia, please interpret it as a generic flood image. Wikimedia Commons, under the terms of the GNU Free Documentation License, Version 1.2

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