Iraqi staff at the ‘world’s most dangerous dam’ dismiss collapse fears

The Mosul dam in northern Iraq has been structurally flawed since it was built. But after it was briefly seized by ISIL, concerns have increased that it may collapse and flood cities downstream. Florian Neuhof visited the dam for The National to speak with those working to keep it standing.

Mosul Dam, Iraq // A few kilometres behind the front lines against ISIL, warm sunshine bathes a giant structure spanning the valley of the river Tigris.

The grey wall of concrete holds back hundreds of millions of cubic metres of water, creating a vast lake behind the dam.

But the integrity of the structure, branded by the US army in 2006 “the most dangerous dam in the world”, is fundamentally flawed by what lies beneath its foundations.

Warnings that Mosul Dam could collapse, sparking a vast human tragedy, have becoming increasingly urgent with the Americans sounding the alarm once again.

In a report published last week, the US Army Corps of Engineers said the structure “is at a significantly higher risk of failure than originally understood” after a recent assessment discovered “an unprecedented level of untreated voids” in its foundations.

Should the dam collapse, a wave up to 20 metres high would hit Mosul within hours, wreaking havoc in the ISIL-held city and beating a path of destruction all the way to the capital Baghdad. Up to 500,000 Iraqis could lose their lives in the catastrophe, according to US officials.

The dam’s vulnerability goes back to its inception. Completed in 1984, it was built on layers of clay and gypsum, which dissolves upon contact with water.

As soon as the dam became operational a year later, creating a 50 kilometre-long lake from the river Tigris, the gypsum began to erode and cavities started to weaken the foundation. To stabilise the structure, the cavities are filled with a cement mix that is injected into the foundation, a practice called “grouting”.

After ISIL seized Mosul in June 2014, its militants surged up the Tigris to seize the dam on August 7. They were pushed back after only 10 days by Kurdish Peshmerga forces, and the Kurds continue to control the dam and its surroundings. But the grouting stopped when ISIL came, and experts fear that the cement mix has since not been injected in sufficient quantities.

“I spoke to one of the engineers at the dam on the phone, they said the grouting has not been the same since ISIL had taken the dam,” says Nadhir Al Ansari, a former adviser to the Iraqi government who now teaches engineering at Sweden’s Lulea University.

“The situation is very dangerous,” he added.

It is not the first time Iraq’s chaotic political situation has undermined efforts to mitigate the dam’s flaws. In 2013, a hinge on one of the two outlets broke, halving the ability to relieve pressure from the gates. Nothing has been done to repair it.

Plans to resume the construction of a secondary dam farther downstream were shelved in 2006.

The US army continues to monitor Mosul Dam closely. When The National visited the site, eight military helicopters were parked close by, and the dam’s management said that the Americans had been coming almost daily since the beginning of February for further inspection.

Sitting in his office overlooking the mighty structure, the dam’s deputy director Mohsin Hassan dismisses concerns about a possible collapse.

“They say that but what evidence is there for this? Our monitoring devices indicate that there is no problem,” said Mr Hassan.

He said a total of 1,250 devices have been installed to check on the state of the dam, that three exploration holes were drilled into the foundation recently and that all findings indicate the dam remains structurally sound.

In spite of admitting that grouting is necessary “24 hours a day”, Mr Hassan denied that the enforced break during ISIL’s time in control of the dam has made the foundation more porous. The cement mix, which was previously produced at a nearby factory, is now imported in sufficient quantities from Turkey, he said, contradicting reports that there is a shortage of material.

At present, 312 full-time employees work to maintain the dam, down from about 400 prior to ISIL, said Mr Hassan, who claims the shortfall in personnel was because some staff are trapped in Mosul, and has been made up for with temporary workers. He insisted that the manpower shortage was not down to unpaid salaries, which a BBC report said had kept half the workforce away. “We are probably only the department that receives its salaries on time,” the deputy director said.

Mr Hassan’s optimism echoes the statements by various government officials, including water resources minister Mohsen Al Shimari, who said in a recent TV interview that grouting would keep the structure stable.

But there are indications the management is worried about the dam. Last month, water was again directed to the hydroelectric power station at the site, which had been shut down to cut off the electricity supply to Mosul. The measure alleviates the pressure on the structure, but contradicts the government’s strategy to deprive ISIL-held territory of basic services by once again supplying electricity to the city.

It remains to be seen how the dam copes with the snowmelt from the mountains in Turkey that swells the Tigris in spring, and whether the damaged water outlets can prevent excessive pressure from building up.

Critics say officials in Baghdad have deliberately been downplaying the dangers.

“The government is trying to calm people down, but they tell a lot of lies,” said Mr Al Ansari, who witnessed the early stages of construction in the 80s and was shocked by the decision to build the dam on such unstable ground. “These officials are really corrupt people. Sometimes they go to the dam and say it is safe because there are no cracks in the structure. For me, that is so stupid. If the dam collapses, it will be within a few minutes, because of the cavities underneath.”

The speed of a collapse would leave little time for those living downstream to get out of the way of the water surging towards them. Mr Hassan says the government has developed an evacuation plan, but admits that “the people might not know about it”.

This information deficit compares unfavourably with contingency planning in other countries, where inhabitants of potentially dangerous areas are well drilled in avoiding disaster, Mr Al Ansari said. “If the people don’t know what to do in case of an emergency, what’s the use of a plan,” he asked.

To make things worse, any crisis management by the government would exclude ISIL-held Mosul, the second-largest city in Iraq and the first to be hit.

In a tacit acknowledgement that something needs to be done to avoid a collapse of the dam, the government has picked Italian company Trevi to undertake essential repairs of the structure. A contract thought to be worth US$300 million (Dh1.1 billion) is expected to be signed soon.

To the Kurdish forces defending the dam against a possible ISIL attack, talk of disaster is overblown. Their focus is on the front lines to the south, where they have been fending off the extremists for more than a year. The road to the dam from nearby Dohuk straddles the front line, and the Kurdish fighters manning the checkpoints say they come under daily mortar fire.

In comparison, the dam is a picture of serenity. Underneath the structure, the Tigris flows quietly. On its shores and the hillsides next to the river, worker accommodation and disused holiday homes sit among fir trees. Behind the dam, the great lake stretches out majestically.

In this peaceful setting, catastrophe seems a remote prospect, and American concern is viewed with suspicion.

“I don’t think that anything will happen to the dam. The US has an interest in saying that because they want their companies to make money,” said an officer with the Asayish, the Kurdish internal security force that controls the dam.