Iraqi engineers involved in building Mosul dam 30 years ago have painted a catastrophic picture of its imminent collapse, saying the death toll from a 20-m-high flood wave could reach one million.
The Iraqi government has urged people to move 3.5 miles away from the river Tigris as fears of collapse grow.
It is going from bad to worse, and it is urgent. All we can do is hold our hearts– Nasrat Adamo, former chief engineer
Engineers say pressure on the dam’s compromised structure is increasing rapidly as winter snows melt and flow into the reservoir, while sluice gates that can relieve the pressure are jammed shut.
Failure to replace machinery or assemble a full maintenance team more than a year after Islamic State temporarily held the dam means that openings in the porous rock under the dam were getting bigger every day, they told The Guardian newspaper.
"We used to have 300 people working 24 hours in three shifts but very few of these workers have come back. There are perhaps 30 people there now," said Nasrat Adamo, the dam’s former chief engineer, who spent much of his career shoring the dam up against construction flaws. The dam, formerly known as ‘Saddam Dam’, was finished in 1986.
"The machines for grouting have been looted. There is no cement supply. They can do nothing. It is going from bad to worse, and it is urgent. All we can do is hold our hearts," Adamo told The Guardian in a telephone interview from Sweden, where he now works as a consultant.
He said the structure would only survive with teams working round-the-clock filling holes in the bedrock.
The Iraqi government on 28 February urged residents of Mosul, Iraq’s second biggest city, to move at least 3.5 miles away from the river.
Some people say there could be half a million people killed, some say a million. I imagine it will be more in the absence of a good evacuation plan– Nadhir al-Ansari, Iraqi engineer
The Iraqi prime minister and the US Embassy in Baghdad both issued urgent warnings about the possibility of the dam collapsing and sending a 20-metre-high flash flood, putting more than a million people at risk.
Speaking to The Guardian, Nasrat Adamo and other engineers warned that the loss of life from a collapse could be even greater than the government’s estimate of 500,000 because many people would die in the resulting mass panic.
Nadhir al-Ansari, another Iraqi engineer who worked on the dam, said the water levels in the reservoir are reaching critical levels, while the dam’s structure is weaker than ever.
"If the dam fails, the water will arrive in Mosul in four hours," he said. "It will arrive in Baghdad in 45 hours. Some people say there could be half a million people killed, some say a million. I imagine it will be more in the absence of a good evacuation plan."
Last month Italian ground engineer and dam specialist Trevi announced that it had been chosen by Iraq’s Council of Ministers on an emergency basis to undertake maintenance on the dam.
Photograph: Aerial view of the Mosul dam and reservoir in 2014. Engineers say the structure’s integrity is fatally compromised while water levels are reaching critical levels (Ali Haidar Khan/Wikimedia Commons)