Poorly constructed Saddam dam could cause flood of biblical proportions

Independent:

As world attention focuses on the daily slaughter in Iraq, a devastating disaster is impending in the north of the country, where the wall of a dam holding back the Tigris river north of Mosul city is in danger of imminent collapse.

"It could go at any minute," says a senior aid worker who has knowledge of the struggle by US and Iraqi engineers to save the dam. "The potential for disaster is very great."

If the dam does fail, a wall of water will sweep into Mosul, Iraq's third largest city with a population of 1.7 million, 20 miles to the south. Experts say the flood waters could destroy 70 per cent of Mosul and inflict heavy damage 190 miles downstream along the Tigris.

The dam was built between 1980 and 1984 and has long been known to be in a dangerous condition because of unstable bedrock. "The dam was constructed on a foundation of marls, soluble gypsum, anhydrite, and karstic limestone that are continuously dissolving," said specialists at the US embassy in a statement. "The dissolution creates an increased risk for dam failure."

In fact the state of the two-mile long earthfill dam, which holds back some eight billion cubic metres of water in Iraq's largest reservoir, has recently been deteriorating at ever-increasing speed. According to one source, the chance of a total and immediate failure of the dam is now believed to be "reasonably high" at current water levels and "most certain" within the next few years.

The effort to prevent the collapse of the dam is overseen by the Iraqi Ministry of Water Resources. The US Army Corps of Engineers has made continual efforts to monitor the deterioration and undertake remedial action. But a US report, obtained separately from the embassy statement, says that "due to fundamental and irreversible flaws existing in the dam's foundation, the US Army Corps of Engineers believes that the safety of the Mosul Dam against a potential catastrophic failure cannot be guaranteed".

Iraq, the site of the biblical flood, is very vulnerable to inundation because it is very flat south of the Kurdish mountains. Prior to the building of dykes and other control measures in the early 20th century, there were frequent disastrous floods when snow melted in the mountains of Turkey.

The great majority of Iraqis live along the Tigris and Euphrates. If the dam does break, specialist sources say that the impact of the flood would be felt all along the Tigris river valley. This would mean heavy damage to cities such as Tikrit and Samarra and the floods could reach as far as Baghdad, home to six million people, though by then the force of the floodwaters should have dissipated.

...

The main method used to strengthen the foundations of the Mosul dam is pumping liquid cement into it or grouting. But a US-funded study concluded that grouting would not save the dam although it did need to be continued and enhanced "to reduce the probability of failure". An international panel of experts called in by the Ministry of Water Resources in Baghdad concluded that a limit should also be placed on the level of the water in the reservoir - that was done in April last year.

...

Here is what they need to do. Gradually reduce the level of the reservoir to a point that does not threaten the dam and then build a new dam in a better location. The electricity generated by the dam is not worth the devastation that would be caused by its eventual failure. The dam was built in the first year of the Iran-Iraq war and typically for Saddam he had no patients for proper engineering and design work.