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A bigger problem than ISIS: The Mosul Dam is failing

newyorker.com

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Re: A bigger problem than ISIS: The Mosul Dam is failing

#61

Post by mynameisvlad »

snowwindwaves wrote: post #50

The Masonry dam in Washington state near Seattle also has/had this problem. The geotechnical reports and conditions were ignored and the water flowed under and around the dam, popping up in all kinds of places. The dam was never able to be filled and is just called the masonry dam since nobody wanted it named after them. https://en.m.wikipedia.org/wiki/Cedar_River_(Washington)

Masonry dam had quite a different problem which is just that there was too much water and it couldn't keep up, so water spilled over the side about 6000ft away from the dam. The problem with the Mosul dam is that it's built on soluble rock that could be swept away with enough pressure. Yes, too much water is the cause of both failures, but they're quite different.

Re: A bigger problem than ISIS: The Mosul Dam is failing

#62

Post by snowwindwaves »

viraptor wrote: post #54
Tuna-Fish wrote: post #11

Earlier quoted context omitted.

> Not that destroying infrastructure and killing the power to a city of civilians, despite ISIS control, is necessarily a good idea, but could they not just cut the lines? Do you know what happens when you run a turbine with nowhere to put the load? 750MW is enough to boil something like a kiloton of water every hour, that energy needs to go somewhere .

Honestly - no, I don't know what happens. Can you tell me? I mean without any modifications that would specifically covert that power into heat, what would happen with the lines cut? Something like the turbines melting, or welding themselves to the structure?

The turbines are Francis type which means they keep spinning until the water flow is stopped.

When a generator is disconnected from the power system without first removing the power from the shaft then power in is greater than power out and the result is an acceleration of the generator. Generators are built to be able to withstand a certain maximum rotational speed without flying apart for a certain duration of time before the bearings get too hot. Of course it can operate at the normal speed forever, but the rated over speed might be twice as fast for 10 minutes.

So when the power lines are cut the turbines and generators speed up until the flow of water is stopped. Pictures of the Mosul dam show four surge tanks, one for each turbine, so they can probably turn off the water in 5-10s.

Pelton turbines are used for higher head and the flow can be maintained without turning the turbine by deflecting the water away from the runner.

I've commissioned about a dozen hydro electric power plants and opening the breaker to simulate cutting the transmission line while making 10, 25, 50,75,100% of the power is standard procedure.

Re: A bigger problem than ISIS: The Mosul Dam is failing

#63

Post by thatguy0900 »

dajohnson89 wrote: post #56
ckarmann wrote: post #51

Earlier quoted context omitted.

You would have to evacuate Mosul (1.7 million people) and probably also Baghdad (7 millions), all in a country thorn by war where refugee camps are already bursting with people. Plus of course the entity that control Mosul (ISIS) is not keen on letting civilians go given their value as human shields.

But this issue with the dam was apparent before ISIS, no?

The article makes it seem like everyone knew it was a bad idea to build it, but Saddam wanted it built and everyone was too afraid/being payed to not say no.

Re: A bigger problem than ISIS: The Mosul Dam is failing

#64

Post by PhasmaFelis »

dajohnson89 wrote: post #56
ckarmann wrote: post #51

Earlier quoted context omitted.

You would have to evacuate Mosul (1.7 million people) and probably also Baghdad (7 millions), all in a country thorn by war where refugee camps are already bursting with people. Plus of course the entity that control Mosul (ISIS) is not keen on letting civilians go given their value as human shields.

But this issue with the dam was apparent before ISIS, no?

The constant infusion of concrete isn't an emergency measure. It's how the dam was intended to operate. The problem (from the planners' point of view, anyway) isn't that it requires constant grouting, it's that it stopped getting constant grouting.

Re: A bigger problem than ISIS: The Mosul Dam is failing

#65

Post by techsupporter »

pasta wrote: post #58
rsync wrote: post #26

Earlier quoted context omitted.

"Amazing read, much longer than I generally get hooked into." Please, please subscribe to the New Yorker in some fashion ... I personally subscribe to the kindle version which is a very useful and workable format. The New Yorker[1] regularly has very, very good long form articles that have deepened my understanding of what I consider to be very important issues. Off the top of my head, I can think of three such artic…

Agreed. If you believe that you should not read main stream news (like I do) this is one of the sources to get 'good' news from.

I don't mean to knock on The New Yorker or cast aspersions on your choices, but I have two rebuttals:

First, longform articles such as this one usually come months or years after the fact and don't help with the primary mission of journalism, which is to keep you abreast of the goings on around you. (Of everything from "what your local government is doing and how that affects you" to "what the financial markets in another continent are up to and how that affects you.") This is my opinion, but I think that the pejorative "mainstream media" is often used as a substitute for "media that doesn't write a story how I want it written."

Second, The New Yorker is owned by Advance Publications, which is about as "mainstream" of media as you're going to find. One of their larger publishing subsidiaries is Conde Nast, which publishes The New Yorker alongside Architectural Digest, Vogue, Golf World, GQ, and several other publications. You may also know them as the publisher of ArsTechnica. They also own more than 40 newspapers.

Just my two cents, for what that's worth these days.

Re: A bigger problem than ISIS: The Mosul Dam is failing

#66

Post by Angostura »

nyolfen wrote: post #41
verelo wrote: post #32

Earlier quoted context omitted.

I often find when I do get lost in an article, it's common to be something from the New Yorker. The articles are very well written and often explore the story in a way that is factual and creative that I really enjoy. Reading "Precedent and Prologue" (Gore V's bush supreme court article) I got so interested in the judicial activism concept and ended up lost on Wikipedia for a few hours bouncing around related article…

it's gotten a lot of buzz lately, including on HN, but if you're interested in going down the gaddafi hole a bit further i'd recommend the recent adam curtis film, hypernormalisation. his films tend to be a bit like getting lost in a wikipedia hole in their own right, though.

You have to be a little careful though - https://youtu.be/x1bX3F7uTrg

Re: A bigger problem than ISIS: The Mosul Dam is failing

#67

Post by SonOfLilit »

dajohnson89 wrote: post #56
ckarmann wrote: post #51

Earlier quoted context omitted.

You would have to evacuate Mosul (1.7 million people) and probably also Baghdad (7 millions), all in a country thorn by war where refugee camps are already bursting with people. Plus of course the entity that control Mosul (ISIS) is not keen on letting civilians go given their value as human shields.

But this issue with the dam was apparent before ISIS, no?

Didn't read the article, but from comments here I understand ISIS is the reason maintenance work halted.

Re: A bigger problem than ISIS: The Mosul Dam is failing

#68

Post by Someone »

abduhl wrote: post #40
lobster_johnson wrote: post #37

Earlier quoted context omitted.

I've seen those, but always assumed they were driving steel beams into the earth. I'm surprised that concrete can be manhandled that way without being smashed into pieces.

Driving concrete piling has generally been abandoned in USA/Canada/Western Europe due to the propensity of concrete to crack in tension during pile driving operations. Driven pile is typically steel now in most construction you will see unless you live in a place where concrete is extremely cheap compared to steel.

Wouldn't that be to crack in compression?

Also, I don't see concrete piles being abandoned at all. Part of the reason may be that, where I live, many poles now are drilled, pressed or vibrated into the ground to decrease noise and potential impact on surrounding buildings.

Thats is possible because there is no bedrock to build on where I live, so poles often go down easily for the first meters; I have seen wooden poles sink in five meters or so under their own weight.

Traditional piling into the ground still is used, too. If necessary, a protective head cover on the pole (made from wood or, nowadays, plastic) softens the blows a bit, protecting the concrete from damage.

Re: A bigger problem than ISIS: The Mosul Dam is failing

#69

Post by grzm »

techsupporter wrote: post #65
pasta wrote: post #58

Earlier quoted context omitted.

Agreed. If you believe that you should not read main stream news (like I do) this is one of the sources to get 'good' news from.

I don't mean to knock on The New Yorker or cast aspersions on your choices, but I have two rebuttals: First, longform articles such as this one usually come months or years after the fact and don't help with the primary mission of journalism, which is to keep you abreast of the goings on around you. (Of everything from "what your local government is doing and how that affects you" to "what the financial markets in an…

longform articles such as this one usually come months or years after the fact and don't help with the primary mission of journalism, which is to keep you abreast of the goings on around you

I think there are many facets to the mission of journalism. In-depth and investigative journalism are very important as well as being kept up-to-date on what's happening in the day-to-day. In some cases I prefer these more in-depth pieces as they have some perspective on how the events they're describing are affected by historical context and how they are affecting what's going on in current events. Consider the Woodward and Bernstein's Watergate coverage or the Boston Globe's coverage of the child sex abuse by Catholic priests in Boston.

Different events and issues can be served by different forms. For a piece like this, I have a hard time imagining it being served better as a short piece of a couple column inches in a paper or a 90 second segment on the evening news. Not all events need coverage like this, of course, but it doesn't make the long-form pieces any less an important and vital aspect of journalism.

Re: A bigger problem than ISIS: The Mosul Dam is failing

#70

Post by grzm »

pasta wrote: post #58
rsync wrote: post #26

Earlier quoted context omitted.

"Amazing read, much longer than I generally get hooked into." Please, please subscribe to the New Yorker in some fashion ... I personally subscribe to the kindle version which is a very useful and workable format. The New Yorker[1] regularly has very, very good long form articles that have deepened my understanding of what I consider to be very important issues. Off the top of my head, I can think of three such artic…

Agreed. If you believe that you should not read main stream news (like I do) this is one of the sources to get 'good' news from.

The Atlantic has good long-form pieces as well: https://www.theatlantic.com
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