The viability of the massive Mosul Dam is in growing doubt. After US warnings were dismissed by current Iraqi officials as overblown, the engineers responsible for building the dam say that the situation is even worse than the US was saying.

ISIS briefly captured the dam over a year ago, and while it was recovered almost immediately, that engineers warn that the Iraqi government has not replaced any machinery since, and has operated on a skeleton crew, meaning the dam has been getting more damaged and more dangerous by the day.

Previous reports suggested that if the dam broke, several hundred thousand people could be killed in Mosul. The engineers are now saying that if it goes, a 20 meter-high flood of water could roll through Mosul and down the Tigris valley, killing upward of a million people.