News

Evacuation plans needed for flood risk area of Pakistan, expert says

(26 March 2010)

Warning systems and evacuation plans are needed to protect people from the potential risk of severe flooding in Northern Pakistan, a Durham University expert says.

Professor Dave Petley, Director of the International Landslide Centre, Durham University, UK, said there was a "substantive risk of an outburst event" this summer caused by a landslide dam in the Hunza area of Pakistan.

The landslide has created a lake that could burst its banks as water levels rise creating a wave up to 20 metres high that could travel hundreds of miles, endangering the local population and damaging infrastructure.

Professor Petley, who has visited Hunza and compiled a report on the landslide dam, said an outburst event was most likely during the period when water was flowing across the spillway*, but could also be triggered by an earthquake or another landslide.

He said it was very difficult to estimate the likelihood of such an event, but based upon experience from other landslide dams "a breach must be considered a real possibility".

Professor Petley added: "It would be sensible to evacuate the vulnerable population from close to the river in the stretches between Attabad and Gilgit, as the water level approaches the spillway.

"Measures should be in place to evacuate the vulnerable population on the remaining stretches of the river at short notice.

"Intense monitoring of the landslide dam is needed, and a warning and communication system should be put in place."

If the dam survives the initial overtopping, monitoring and evacuation plans will be needed through the summer and beyond to provide a warning should a sudden breach occur, Professor Petley said.

People upstream of the dam are currently isolated and a large-scale effort is needed to ensure they have access to the required resources to sustain them, he added.

Professor Petley's visit to Hunza was courtesy of Focus Humanitarian Action.

*The spillway is a channel being dug across the top of the landslide to try to reduce the total volume of water that will be behind the dam when it is overtopped. The aim is to build a channel that allows the flood to be controlled.