"All we can do is hold our hearts."
March 3, 2016 8:27 AM   Subscribe

Building a hydro-electric dam on a bed of water-soluble gypsum was never the best idea, but engineers kept it under control for thirty years by filling any holes that appeared in the bedrock with cement (a process known as grouting). Now the repair workforce has fallen by 90%, the bedrock is getting weaker, the sluice gates are jammed, and spring meltwater threatens to burst the dam and send a wall of water twenty metres high flooding towards the cities downstream.

The nearest city? Mosul, in Iraq, occupied by ISIS since June 2014. Downstream lie Tikrit, Samarra and Baghdad. The US Embassy in Baghdad issued a warning on Sunday that the dam could fail at any time, recommending that residents of Mosul, Tikrit and Samarra move 5 to 16.5km away from the banks of the Tigris. Parts of Baghdad would also be flooded if the dam bursts. In the absence of sufficient warning, a million people could die.

Iraq's minister of water resources said last month that there was only a "one in a thousand" chance the dam would collapse, and the government has reached a tentative agreement with an Italian firm to repair it. But the dam's former chief engineer says that the situation is urgent, and that "all we can do is hold our hearts".

Previously.
posted by rory (34 comments total) 16 users marked this as a favorite
 
If the bedrock underneath the dam is shot, then can there even be a long term solution, short of "build a bigger dam right beside this one"?
posted by wenestvedt at 8:40 AM on March 3, 2016 [2 favorites]


They did start on a second dam as a safety feature. From the Guardian article:

A second structure, the Badush dam, was started 20km downstream, to prevent a catastrophe in the event of the Mosul dam’s failure. But work on Badush halted in the 1990s because of the pressure of sanctions, leaving it only 40% complete.
posted by dowcrag at 8:51 AM on March 3, 2016 [4 favorites]


Allah [continue to] be merciful.
posted by RolandOfEld at 8:52 AM on March 3, 2016 [4 favorites]


Is there any way to slowly let water out of the reservoir until the damn can be taken down? I realize that there are going to be issues with whatever power/water it supplies, but that can't be worse than killing at least half a million people.
posted by Hactar at 8:52 AM on March 3, 2016 [4 favorites]


Holy cow. This looks to be very similar to the Teton Dam collapse, except in that case the downstream population was something like 95% livestock and so the loss of life was minimal compared to how catastrophic the failure was. (You can see that failure at about the 1:45 mark here.) I had no idea we were still building dams on top of such porous material -- in theory, at least, one of the takeaways from the Teton Dam was "don't do that." (It looks like the Mosul dam is concrete instead of the piled dirt/scree/etc used in the Teton Dam, but either way, unexpected flow = erosion = eventual collapse.)
posted by range at 8:53 AM on March 3, 2016 [5 favorites]


During a season of excessive rain here in New England some years ago, it was sheepishly revealed that there were many privately-owned and very poorly maintained earthen dams, right by residential areas. The predicted effects of a failure were awful -- and immediate, which made the threat scarier.

Naturally, when the rains dried up, nothing was done AFAIK.
posted by wenestvedt at 9:05 AM on March 3, 2016 [3 favorites]


If the bedrock underneath the dam is shot, then can there even be a long term solution, short of "build a bigger dam right beside this one"?

Wolf Creek Dam in Kentucky was built on similar water soluble limestone, resulting in similar problems with seepage under the bedrock undermining the dam. It could have failed in the same manner, swamping Nashville and Clarksville TN. The solution was to dramatically lower the level of Lake Cumberland behind the dam for 3 years, to relieve the stress while a new concrete retaining dam was built under and extending the existing dam. Basically they rebuilt it deeper and longer, with more water resistant modern concrete. Supposedly that should be a permanent fix.

I imagine the plan for the Mosul dam would be very similar.
posted by T.D. Strange at 9:05 AM on March 3, 2016 [10 favorites]


Dam.
posted by ElDiabloConQueso at 9:07 AM on March 3, 2016


I didn't want the initial post to get too long, but as you'll see from the links, one of the ironies here is that the brief two-week takeover by ISIS forces of the Mosul dam in 2014 is what disrupted the maintenance regime; many of the workers fled and didn't return, and ISIS destroyed a lot of the grouting equipment.

The Italian firm bidding to repair the dam is factoring in 450 security staff. Hope it's enough.
posted by rory at 9:08 AM on March 3, 2016 [4 favorites]


During a season of excessive rain here in New England some years ago, it was sheepishly revealed that there were many privately-owned and very poorly maintained earthen dams, right by residential areas.

A privately-owned, poorly maintained earthen dam was the cause of the Johnstown Flood.
posted by Chrysostom at 9:09 AM on March 3, 2016 [5 favorites]


I forgot to mention, the Wolf Creek rehab project was completed by the same Italian firm.
posted by T.D. Strange at 9:10 AM on March 3, 2016


The solution was to dramatically lower the level of Lake Cumberland behind the dam for 3 years

Unfortunately, the sluice gates at Mosul dam have been jammed since 2013.
posted by rory at 9:14 AM on March 3, 2016 [2 favorites]


Is there any way to slowly let water out of the reservoir

Yes, but the gate is broken. Expensive repair in the middle of a war zone, with no funds and fewer engineers.
posted by sammyo at 9:14 AM on March 3, 2016 [5 favorites]


What rory said.
posted by sammyo at 9:15 AM on March 3, 2016


Evil black cynic sez: push ISIS into Mosul for a last stand, then wait.
posted by sammyo at 9:17 AM on March 3, 2016 [6 favorites]


Unfortunately, the sluice gates at Mosul dam have been jammed since 2013.

Right, they'd probably have to restart the emergency grouting while the dam itself was repaired, then get to lowering the water level to start the permanent fix. It's bad. It'd be a years long repair even without the security concerns, which could goto hell in a matter of days or hours.
posted by T.D. Strange at 9:29 AM on March 3, 2016 [1 favorite]


Oddly relieved that this was built under Saddam's regime and not by the American occupation. At least one tragedy in the region that can't be blamed on us!

Oh, wait, it's ISIS' fault that the dam can't be repaired? Guess we're culpable anyway. Oops.
posted by tobascodagama at 9:29 AM on March 3, 2016 [3 favorites]


Thanks, Osama!

Oh, wait...
posted by wenestvedt at 9:36 AM on March 3, 2016 [1 favorite]


An international conference has been announced in Rome in April to discuss ways of preventing a disaster, but by then it could already be too late.

Ah an international conference where discussions will be had. This surely will solve the problem in a timely manner!
posted by bitteroldman at 10:01 AM on March 3, 2016 [3 favorites]


Ah an international conference where discussions will be had. This surely will solve the problem in a timely manner!

"First on the agenda, gentlemen... this room is now being loaded into the hold of a C-5 Galaxy strategic airlifter. We arrive in Mosul in five hours. Each of you has a notebook and a pen, and these three whiteboards. Get to work."
posted by Etrigan at 10:19 AM on March 3, 2016 [13 favorites]


Each of you has a notebook and a pen, and these three whiteboards. Shovels will be provided upon arrival. Get to work.
posted by j_curiouser at 11:23 AM on March 3, 2016 [1 favorite]


Yes, but the gate is broken. Expensive repair in the middle of a war zone, with no funds and fewer engineers.


Install a siphon over the dam, prime it and let it run? That's good for a few meters at least.
posted by ocschwar at 11:58 AM on March 3, 2016 [1 favorite]


Im not sure where the international debate thing came up, all the recent articles say the contract with the Italian firm IS signed, and Italy IS sending 450 troops to safe guard the project. But it could take 2-3 months to even get started. I guess it's just cross your fingers it doesn't let go before then.
posted by T.D. Strange at 12:32 PM on March 3, 2016 [1 favorite]


I forgot to mention, the Wolf Creek rehab project was completed by the same Italian firm.

They sound like the right people for the job, but this job has been neglected for so long it might be impossibly dangerous. Imagine trying to build a mega-project next door to ISIS, with the threat of catastrophic structural failure hanging over your head the entire time. If they succeed it'll be one heck of a story.
posted by Kevin Street at 2:11 PM on March 3, 2016 [3 favorites]


I want to watch that movie.
posted by tobascodagama at 2:46 PM on March 3, 2016 [1 favorite]


At least one tragedy in the region that can't be blamed on us!

The article blames the failure to complete the second dam (which would have been a long-term solution) on the international sanctions of the 90s, so...
posted by BungaDunga at 3:31 PM on March 3, 2016


Couldn't they use some C-4 to cut a hole in the stuck sluice gate, and its mate?... they can weld a patch over it when they get done with the grouting.
posted by MikeWarot at 4:26 PM on March 3, 2016


High explosives would seem to mix poorly with unstable foundations.
posted by tobascodagama at 4:35 PM on March 3, 2016 [3 favorites]


People tend to wildly underestimate the force of even small amounts of water (which is why Youtube is full of videos of people getting swept downstream in their cars), and the impact of a dam breach is catastrophic. I hope they can get this fixed, though obviously the only long term solution will be to bring peace to the region.
posted by Dip Flash at 5:38 PM on March 3, 2016 [1 favorite]


This disaster is about 1000x more likely in the near future as a Cascadia Subduction fault earthquake and Tsunami off the Oregon coast. A million or more people will probabaly be killed. That is 10x the death toll from the Indian Ocean Christmas Tsunami. The number of displaced people will double the number displaced by Syria.

Tldr the short sighted MBA trained management class once again sacrificed millions for ther promotions and bonuses.
(Details follow)
The US Army Corps studied the dam during the Iraqi occupation. They wanted to drain the lake immediately. However the suits in charge had key performance indicators and target metrics that drove promotions and bonuses. Two big ones were water supplies and electricity. The theory being the more the lights are on and the water is flowing from the tap and into the fields; the better things are going. So the recommendation of the US Army Corps of Engineers was rejected because you drains the lake, the Iraqi power grid takes a huge hit as do the water supplies. Since these suits are only there for 18months to 2years they just gamble that it won't collapse on their watch.
posted by humanfont at 6:48 AM on March 4, 2016 [2 favorites]


While the potential for a massive humanitarian disaster is abundantly clear, the scenario described will also wipe out thousands of archaeological and cultural sites along the Tigris River, including many that have already been damaged or destroyed by the Islamic State (commonly known as ISIS).

The Assyrian sites of Nimrud, Nineveh and Khorsabad, once capitals of one of the world's first true empires in the first millennium B.C., are in [the] projected path of a deluge resulting from a dam failure.
posted by rory at 8:48 AM on March 4, 2016 [1 favorite]


Before I came in here, I assumed the dam in question was the one in Africa I just read about in the New Yorker.
posted by Rash at 7:46 AM on March 5, 2016 [1 favorite]


Evil black cynic sez: push ISIS into Mosul for a last stand, then wait.

That makes me wonder how vulnerable to sabotage the dam is as it stands and whether that's too far or too inappropriate a casualty set for ISIS.
posted by phearlez at 1:10 PM on March 5, 2016


The article blames the failure to complete the second dam (which would have been a long-term solution) on the international sanctions of the 90s, so...

Someone should ask Madeleine Albright if she still thinks the price of sanctions was worth it.
posted by homunculus at 10:14 PM on March 6, 2016 [1 favorite]


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