Pakistan-Why is the Indus so flood prone?

Peter Bosshard

The recent flood disaster may occur again

As we write this, Pakistan is still under water, and millions are coping with the aftermath of the hugely destructive floods. But once the water has subsided and the victims have received support, Pakistan and the international community will need to learn the lessons of the current disaster. Are the floods a natural or a human-made disaster? What kind of flood management will help to prevent or mitigate future catastrophic floods in a time of climate change?

Daanish Mustafa, a water expert from Pakistan who teaches at King’s College in London, shed light on the current Pakistan flood disaster in a recent interview with the BBC. Mustafa explains that by walling in the Indus and destroying natural floodplains, Pakistan has substituted high frequency, low-intensity floods for low-frequency, high-intensity events.

“Unfortunately, the river managers in Pakistan ... do not recognize the importance of wetlands to modulating the flow,” said Mustafa. “Instead, The focus has been on dams, which have their usefulness, but wetlands unfortunately have been drained and settled and removed. As a result, the river’s excess water has nowhere to go.”

The Indus has one of the highest silt loads in the world. Due to dam building, the silt now gets deposited in the riverbed and reservoirs. As a consequence, the riverbed is elevated, its capacity to drain floodwater dwindles, and the pressure on the levees increases. Dam builders have often failed to take such changes into account.In October 2004, the World Bank rehabilitated the Taunsa Barrage on the Indus at a cost of $144 million.

Mushtaq Gaadi, who teaches at Quaid-i-Azam University in Islamabad, notes that local NGOs objected to the rivers engineering perspective and urged the World Bank to pay more attention to the sediment deposition. The Bank refused. Now the embankments near the barrage have breached, and caused huge devastation in areas that are not normally flooded. “The very structures meant to control flooding have partially caused and definitely exacerbated the flood problem itself,” Gaadi concludes.

Due to climate change, extreme weather patterns such as the current floods are becoming more and more frequent. Managing floods is a more appropriate response to such a scenario than trying to control them. According to Mustafa, “The kind of monsoon patterns you are seeing this year is very unusual.

The scary part is we have seen this sort of unusual monsoon pattern about four or five times this past decade... The fundamental message is that the past averages are not going to hold. There is going to be greater uncertainty in the future. That being the case, then we have to be a lot more proactive and have to think about, well, if this becomes the pattern, then what?” – Third World Network Features. Peter Bosshard is Policy Director of International Rivers.