“….in terms of internal erosion potential of the foundation, Mosul Dam is the most dangerous dam in the world… If a small problem [at] Mosul Dam occurs, failure is likely.”

 U.S. Army Corps of Engineers, September 2006



Key Facts

  • The Mosul Dam provides critical irrigation, flood control, and hydropower to NW Iraq
  • Leaks were discovered within months of operation
  • U.S. Army study concludes that the dam is at a “high risk” of failure 
  • Projected loss of life from dam failure 500,000 (U.S. Embassy est. 1.47 million)
  • Only permanent solution is to construct a second dam at estimated cost of $2 billion


Mosuldam (1)

Mosul Dam

  • Located on Tigris River in Northwest Iraq 60 km (37 miles) north of Mosul
  • Fourth largest dam in the Middle East with over 11.11 billion cubic meters of storage; equivalent to twice the size of Lake Pontchartrain – the lake that broke the levies in New Orleans
  • Operated by Iraqi Ministry of Water Resources

Structural problems

  • Built on soft, dissoluble Gypsum, Anhydrite and karstified limestone bedrock
  • Foundation has been severely eroded by water (karstified)
  • Short-term solution has been constant mass-scale grouting (cement filling)


Mosuldam2Safety concerns

  • Dam’s safety problems concealed by Ministry until a post-2003 US Army Corps of Engineers investigation
  • The study reports that grouting is not a viable long-term solution
  • Study reports that the soft Gypsum and Anhydrite foundation will collapse from dam weight and water erosion
  • Only permanent solution is to build a second dam at cost of $2 billion





 Consequences of the Dam failure

  • Projected loss of life from total dam failure is 500,000 (the U.S. Embassy in Baghdad have even estimated that this could grow to 1.47 million without adequate evacuation)
  • The initial wave will peak at 55m (180 ft) and reach Mosul city within 4 hours of dam failure
  • Floodwater will reach the capital city within 38 hours and will inundate a 261km (138 miles) area of Baghdad 10 hours after that
  • Flooding will eventually stop 700km South of dam (15 miles south of Baghdad) after 48 hours, having caused an “enormous” loss of life and property
  • PM Al-Abadi’s government has downplayed safety risk and rejected new dam construction



  • Originally called Saddam Dam, construction began in 1981 and made operation by 1986
  • A Ba’athist Party deputy under Saddam chose the site to bring jobs to Mosul
  • Daesh (IS) captured the dam for several weeks in July 2014, generating concerns of a planned demolition
  • Currently, Daesh is in control of Mosul city 50km (30 miles) SE of the Dam

Taken From a Report on “Geological and Engineering Investigations of the World’s Most Dangerous Dam” Report by Dr. Al-Ansari


Media References:

Fearing a Flood

-Patrick Martin, Globe and Mail (11 Apr 2016)

-“Iraq is facing an unprecedented threat from the giant Mosul Dam, upstream from its biggest cities, which U.S experts warn is in danger of bursting and unleashing a catastrophic tsunami-like wave.”



Inside the World’s Most Dangerous Dam

-Arwa Damon, CNN (8 Apr 2016)

– In a recent security message, the U.S government said if the dam collapses, “Some models estimate Mosul could be inundated by as much as 70 feet (21 meters) of water within hours of the breach…the lives of at least 1.5 million people could be at risk, according to U.S estimates.”


Time to Prevent a Flood in Iraq 

– Florian Neuhof, National Editorial (27 Mar 2016)

– “For several months, the strength of the Mosul dam in northern Iraq has been in question. The dam secures more than 11 billion cubic metres of water. If it were to burst, the city of Mosul would be submerged within four hours. In a matter of days, the water would reach Baghdad and up to one million people could be dead.”


 Iraq’s Mosul Dam At Risk of Bursting as Erosion Takes Its Toll

– Ahmed Maher, BBC (22 Jan 2016)

– “Budget shortfalls due to the slump in oil prices and political rivalry between the central government in Baghdad and the regional government of the semi-autonomous Iraq Kurdistan have hampered urgently needed repairs.”


Iraq’s Mosul Dam in Critical Need of Repair

– Nadhir Al-Ansari, NPR (05 Mar 2016)

– “Really, I am very frightened. They don’t have that much material and the machinery are not enough to do the required quantities of grouting. So we are very worried that if a flood comes next month, that might destroy the dam.”


US Army: Iraq’s Mosul Dam at Higher Risk of Failure

– Fox News (09 Feb 2016)

– “Iraq’s Mosul Dam has long been branded the world’s most dangerous dam, at risk of collapsing and sending water crashing over millions of people. That prospect is even greater than was previously believed after the Islamic State group captured the dam briefly in 2014, according to a new report by U.S. Army engineers.”


Italy’s Trevi Sign Deal to Repair Mosul Dam After U.S Warning

– Chiara Albanese et al., Bloomberg (02 Mar 2016)

– “An Italian engineering company will oversee repairs to Iraq’s largest dam, which the U.S. embassy in Baghdad said this week could fail catastrophically with little warning.”


Italian Firm Trevi to Fix Iraq’s Imperilled Mosul Dam

– ABC Australia (02 Feb 2016)

– “The Mosul Dam was built on an unstable foundation that continuously erodes, and a lapse in maintenance after the Islamic State jihadist group seized it in 2014 weakened its already-flawed structure.”


Iraq Government Plays Down Mosul Dam Collapse Threat Report

–  Agenzia Ansa (11 Mar 2016)

– “The Iraqi government on Friday played down reports from the United States and the United Nations that the key Mosul Dam is in danger of imminent collapse. The alerts are “not correct” and “unrealistic,” said an aide to the Iraqi water resources ministry.


A Watery Time-Bomb: the Most Dangerous Dam in the World

– The Economist (13 Feb 2016)

– “One study says that if the dam collapses, Mosul would be submerged within hours. Another warns that half a million Iraqis could be killed by floodwaters, and more than a million forced from their homes. Disease and looting as the floodwaters raced through Baiji, Tikrit, Samarra and even parts of Baghdad would complete that dreadful scenario.”


US Plays Up Growing Risks at Mosul Dam

– Nour Malas, Wall Street Journal (29 Feb 2016)

– “The U.S. government on Sunday warned of an unprecedented risk of catastrophic failure with little warning at Iraq’s largest dam, while Baghdad played down the potential dangers.”


Obama Intervened Over Crumbling Iraqi Dam as U.S Concern Grew

– Warren Strobel et al., Reuters (22 Mar 2016)

– “Obama’s confidential message to Haider al-Abadi…was not about Islamic State or Iraq’s sectarian divide. It was about a potential catastrophe posed by the dire state of the country’s largest dam, whose collapse could unleash a flood killing tens of thousands of people and trigger an environmental disaster.”


Mosul Dam at Risk of “Catastrophic Failure”

– Lorenzo Ferringo, CNN (10 Mar 2016)

– “The largest dam in Iraq is facing an “unprecedented risk of catastrophic failure with little warning,” prompting a “chilling” meeting at the United Nations Wednesday morning.”


A Catastrophe of Epic Proportions

– Nial Ferguson, Boston Globe (14 Mar 2016)

– “There is a powerful symbolism in the impending collapse of Iraq’s Mosul dam. Built on the cheap by Saddam Hussein in the early 1980s, it holds back up to 2.9 trillion gallons, roughly twice as much as Lake Pontchartrain in New Orleans. We all know what happened when Hurricane Katrina breached the levees around Pontchartrain’s south shore in 2005.”


Doomsday Dam Could Bring Iraqi’s Together

Wilson Dizzard, Al Jazeera (20 Aug 2014)

– “Fearing such an epic disaster, two of Iraq’s three main powers, the Shia Arab-led government in Baghdad and ethnic Kurds, who are Sunnis, have already started to work together, an Iraqi diplomat said, speaking on condition of anonymity because he was not authorized to speak to the press.”


Iraq Assualt to Retake Mosul From ISIL Months Away

–  Al Jazeera (06 Mar 2016)

– “The military operation to retake Iraq’s second-largest city from ISIL is months away, or longer, military officials say, despite repeated claims by its prime minister that the armed group will be ousted from Mosul by year’s end.”


Real Or Imaginary Threat?

– Jordan Times (26 Mar 2016)

-“Iraq could be facing a human and environmental disaster of great proportions if the Mosul Dam, on the Tigris River, is not attended to, and fast, US experts say.”


This Fragile Iraqi Dam Could Pose A Bigger Threat Than ISIS

– Rebbeca Collard, Time (26 Mar 2016)

-“an even greater threat than ISIS: the deteriorating Mosul Dam, whose collapse would send a wall of 11 billion cubic meters of water crashing toward Iraq’s second biggest city, killing more Iraqis in minutes than the total dead since the U.S. invasion of 2003.”



Hydro-politics of the Tigris and Euphrates River Basin

-Dr. Nadhir Al-Ansari (14 Mar 2016)

-” The Middle East is characterized by its water shortage problem where at least 12 countries have acute water scarcity problems with less than 500 cubic meters of renewable water resources per capita available.The supply of fresh water is essential to life, socioeconomic development, and political stability in this region.”


Geological and Engeneering Investigations of the Most Dangerous Dam in the World

– Dr. Nadhir Al-Ansari (29 Nov 2016)

-“Extraordinary engineering measures” to fill soil gaps and “maintain structural integrity and operating capability of the  dam” are a must, according to the US Army Corps of Engineers.”


Senate Armed Services Committee Hearing on Combating Terrorism

– CENTCOM Commander Gen. Lloyd Austin, C-SPAN (08 Mar 2016)

– “If the damn fails, it will be catastrophic. There will be thousands of people downstream that will be injured or killed, and certainly displaced.”


Relief and Reconstruction Funded Work at Mosul Dam

– Office of the Inspector General for Iraq Reconstruction

-“…in terms of internal erosion potential of the foundation, Mosul  Dam is the most dangerous dam in the world… If a small problem [at] Mosul Dam occurs, failure is likely.”