Iraq's 'most dangerous dam' at 'higher risk' of failure

"Signs of distress" have been identified at Iraq's Mosul Dam, indicating that it is at "significantly higher risk of failure" than previously understood.

The internal assessment by the US Army Corps of Engineers was made public by the Iraqi parliament on Monday and concludes that the risk of the dam failing has increased over the past year.

Previous studies have warned that more than half a million people downstream in the Tigris valley could die if Mosul Dam were to collapse, or be destroyed.

The assessment is dated January 30, just days before Iraq's prime minister awarded an Italian firm a contract to overhaul and maintain the dam.

However, there seems to be conflicting reports surrounding any risks of collapse.

Only days ago, Iraq's minister of water resources said there was a "one in a thousand" chance of failure.

"The looming danger to Mosul Dam is one in a thousand. This risk level is present in all the world's dams," Mohsen al-Shammari told a local TV station.

"The talk about a large wave that a collapse could create is unlikely, because the dam would have to be at full capacity, when it is currently operating at a fourth of that - and that is in the extremely unlikely event of a collapse," Shammari added.

The most dangerous dam in the world?

Built in the early 1980s, the Mosul Dam is the largest in Iraq and the fourth-largest in the Middle East.

It is made largely of earth and situated on soft mineral foundations, which are easily dissolved by water.

Following the 2003 US invasion of Iraq, American military officials repeatedly sounded warnings about the dangers the dam posed.

A report by the US Army Corps of Engineers in 2006 called it "the most dangerous dam in the world" because of its propensity to erode.

In 2007, the US ambassador to Iraq and the top American military commander in the country wrote a letter warning that the dam could fail - with devastating results.

"A catastrophic failure of the Mosul Dam would result in flooding along the Tigris River all the way to Baghdad," the letter said.

A catastrophic failure of the Mosul Dam would result in flooding along the Tigris River all the way to Baghdad

Concerns increased sharply after the Islamic State group briefly took control of the dam in July 2014.

Although Iraqi forces and Kurdish fighters, with air support from the coalition, took the area back from IS control within weeks, some experts believe that the group's temporary takeover interrupted protective work on the dam.

As maintenance teams struggled to gain access to the site, this increased the risks of its collapse.

Last week, Iraqi Prime Minister Haider al-Abadi formed an emergency committee to investigate reports that new cracks had developed in the dam.

The 2006 report by the corps said the dam's collapse would put Mosul - Iraq's second-largest city - under 20 metres of water.

An Iraqi official said the dam's collapse would "swallow up" entire cities, putting the lives of millions of Iraqis in danger.

"Iraq is on the brink of a massive humanitarian and environmental disaster because of the dam. It could collapse as soon as April because at that time of year it will be under pressure from rain and thawing snow," an Iraqi official told The New Arab.

According to a Foreign Policy report, a team of researchers at a university in Sweden compiled many of the simulations done for a dam breach, as part of a wider study.

The researchers found that within about four hours, Mosul would be facing a wave of water almost 80 feet high; flooding would cover about 28 square miles.

Within 22 hours, Saddam Hussein’s hometown of Tikrit would be hit with a 50-foot wall of water.

And within two days of a dam breach, Baghdad itself - 400 miles downriver - would have 13 or so feet of water all over the centre of the city, and flooding would cover more than 80 square miles around the capital.

Within two days of a dam breach, Baghdad itself - 400 miles downriver - would have 13 or so feet of water all over the centre of the city, and flooding would cover more than 80 square miles around the capital

Rehabilitation and maintenance

Earlier this month, Iraq announced it had awarded an Italian firm, Trevi, a contract to repair and maintain the dam.

The Iraqi cabinet, with the agreement of the Ministry of Water Resources, awarded Trevi the contract "to carry out the project of rehabilitating and maintaining the Mosul Dam", a government statement said.

The Trevi Group has carried out similar work at more than 150 other troubled dams, including in the United States.

The deal has reportedly yet to be signed, according to the statement, which did not specify how much Trevi would be paid for the work.

Nadhir al-Ansari, a civil engineering professor at Sweden's Lulea University of Technology, who has spent years studying the dam, specifically recommended that the Iraqi government forget the idea of building a cut-off wall, warning that it "could endanger the integrity of the dam itself".

"I don't think it is a good solution," Ansari told Foreign Policy, stating that a better way to prevent flooding was to build a retaining dam further downstream on the Tigris River.