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Great Man-Made River

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Re: Great Man-Made River

#31

Post by azernik »

einpoklum wrote: post #29
adolph wrote: post #27

Earlier quoted context omitted.

For question one, Wikipedia refers to the source as a “fossil” aquifer, meaning the water has been in place for many thousands of years. It also claims the source is rainwater and doesn’t make an estimate about balance of inputs to pumping effort outputs. https://en.wikipedia.org/wiki/Nubian_Sandstone_Aquifer_Syste...

If that's really the case, pumping it out sounds like a fool's errand, because it'll just run out. Either that or it's so vast that consumption by millions of people doesn't make a dent in the overall water level.

Even with zero influx, at current estimated usage it should last about 100K years

Re: Great Man-Made River

#32

Post by [deleted] »

azernik wrote: post #31
einpoklum wrote: post #29

Earlier quoted context omitted.

If that's really the case, pumping it out sounds like a fool's errand, because it'll just run out. Either that or it's so vast that consumption by millions of people doesn't make a dent in the overall water level.

Even with zero influx, at current estimated usage it should last about 100K years

[deleted]

Re: Great Man-Made River

#33

Post by thendrill »

einpoklum wrote: post #29
adolph wrote: post #27

Earlier quoted context omitted.

For question one, Wikipedia refers to the source as a “fossil” aquifer, meaning the water has been in place for many thousands of years. It also claims the source is rainwater and doesn’t make an estimate about balance of inputs to pumping effort outputs. https://en.wikipedia.org/wiki/Nubian_Sandstone_Aquifer_Syste...

If that's really the case, pumping it out sounds like a fool's errand, because it'll just run out. Either that or it's so vast that consumption by millions of people doesn't make a dent in the overall water level.

Yeh but you have to remember that Libya was and is still floating on oil.

Also this was the 70s ... Good time for oil. So basically Libya has this free black money comming from the desert. Yet people struggle with basic infrastructure. Also keep in mind that Libya was around 6 mill people. Not a lot for such a vast desert.

So basically two birds with one stone... You build up your infrastructure connecting the coast and the desert and in the process you get much needed water delivered to the coast.

Yes the water might not be there. But you still have a super highway build in the desert.

If you look at UAE and KSA that is exactly what they did too. Invest as much as possible in infrastructure, NOW... roads, pipes, cables etc.

"Long term" does not play well in Arabic culture....

Re: Great Man-Made River

#34

Post by octocop »

Viker wrote: post #6

I grew up in Libya during the building of the GMMR. I still remember the size of the pipes and the amount of trucks hauling them. One truck one pipe. https://en.m.wikipedia.org/wiki/Nubian_Sandstone_Aquifer_Sys... The Korean companies (Daewoo mainly I think) building the project were massive. They would build a double lane road. One side would be used exclusively for one direction pipe supplies and machines. Eventual…

What do you think of Gaddafi? I read on wiki he said that GMMR was the eighth wonder of the world.

Re: Great Man-Made River

#35

Post by scythe »

f6v wrote: post #19
cheph wrote: post #14

Earlier quoted context omitted.

Remind me again why the fuck Obama rallied NATO to fuck that country up again and how Obama is still seen as the messiah to socialist and progressives after doing that?

It wasn’t just Obama. France, Italy, and Turkey perpetuate the conflict.

Obama didn't even "rally NATO" at all. France was the first mover.

https://en.wikipedia.org/wiki/2011_military_intervention_in_...

>23 February 2011: French President Nicolas Sarkozy pushed for the European Union (EU) to pass sanctions against Gaddafi (freezing Gaddafi family funds abroad) and demand he stop attacks against civilians.

>26 February 2011: United Nations Security Council Resolution 1970 was passed unanimously, referring the Libyan government to the International Criminal Court for gross human rights violations.

>28 February 2011: British Prime Minister David Cameron proposed the idea of a no-fly zone

>1 March 2011: The US Senate unanimously passed non-binding Senate resolution S.RES.85 urging the United Nations Security Council to impose a Libyan no-fly zone

>2 March 2011: The Governor General of Canada-in-Council authorised, on the advice of Prime Minister of Canada Stephen Harper

>7 March 2011: US Ambassador to NATO Ivo Daalder announced that NATO decided to step up surveillance missions of E-3 AWACS aircraft to twenty-four hours a day.

France, the UK, the UNSC, the US Senate, and Canada all made moves before Obama's executive branch took any major actions. (Notably, all except the UNSC were controlled by right-wing political parties at the time.) But Obama is the most popular political figure in the country and has been for a decade, and it's lonely at the top...

https://today.yougov.com/ratings/politics/popularity/politic...

Re: Great Man-Made River

#36

Post by mlillie »

carschno wrote: post #28
cheph wrote: post #14

Earlier quoted context omitted.

Remind me again why the fuck Obama rallied NATO to fuck that country up again and how Obama is still seen as the messiah to socialist and progressives after doing that?

Would you have one example of "how Obama is still seen as the messiah to socialist[s]"?

Yeah, socialist here, and I am absolutely no fan of Obama's...

Re: Great Man-Made River

#37

Post by Tuna-Fish »

Viker wrote: post #25
lsmurray wrote: post #11

Earlier quoted context omitted.

Is there any worry about what would happen if the water supply runs out? The article noted that the GMMR might run out in 60-100 years and supplies millions of people with water.

I think the water supply ran out..

There is still plenty of water there. What they failed at was that they greatly overestimated how permeable the sandstone that holds the water is. That is, the flow of water sideways in the aquifer is much slower than expected. They pumped the area directly under the pumps almost dry and then were surprised about how slowly it refilled.

It would still be possible to fix this and reach the original targets by building more pumping stations, further away from each other than the existing ones. That or frack the rock formation...

Re: Great Man-Made River

#38

Post by cmpb »

cookiengineer wrote: post #7

I am always amazed by human engineering. I grew up near the Rhine in Germany, and literally they changed the position of the whole river into a different shape, depth, and form so that ships can flow on it. The planning of the event was called "Rheinbegradigung" [1] and they made the river straight, with lots and lots of watergates in between from the Ocean right up to Basel in Switzerland. Eversince I grew up, hundr…

I don't mean to be a wet-blanket with my comment, just to point out the potential negative impacts of human engineering, when such engineering is not well-thought-out.

We (in gulf south US) have had similar engineering projects with the Mississippi River (et al) over the course of the last couple of centuries. Largely the goal has been to keep the rivers from flooding their banks, which they are keen to do in various places, mostly yearly. The impetus for this is of course to aid in the development of major cities and keep farmlands productive.

What is happening as a result, however, is now known to be truly disastrous for my home state of Louisiana, where the adage is "Louisiana is losing a football field an hour"[0] due (in large part) to the levees preventing the sediment from the rivers from depositing along the coast and helping to keep the coastal marshes in place. There are other (secondary) ill effects as well, that are perhaps more subtle. I was on a native plant society field trip last week to study one of our more southerly "bottomlands" (mixed swamp/marsh/upland habitat). What we found is that many of the freshwater-wetland-specific trees are becoming severely unhealthy and/or dying due to the influx of brackish water (mixed salt/fresh) from the gulf/lakes in the area. This is largely due to the loss of sediment that normally would be deposited from the Mississippi river - that sediment helps to reform the uplands surrounding the bottomlands, and without it, other water sources are able to carve a path in. Some of this, of course, is natural, and part of how Louisiana's wetlands normally change over time, but they do seem to be changing more rapidly.

Fortunately, there is a large amount of interest among Louisianians to fix these problems. There are some more large engineering projects designed to undo some of this damage, specifically with projects to reroute the sediment to where its needed (aka diversions)[1]. So I'm hopeful we'll be able to stop and maybe reverse the damage being done

[0] https://www.nola.com/news/environment/article_3128024a-cc03-... [1] https://coastal.la.gov/midbarataria/

Re: Great Man-Made River

#39

Post by Tuna-Fish »

einpoklum wrote: post #29
adolph wrote: post #27

Earlier quoted context omitted.

For question one, Wikipedia refers to the source as a “fossil” aquifer, meaning the water has been in place for many thousands of years. It also claims the source is rainwater and doesn’t make an estimate about balance of inputs to pumping effort outputs. https://en.wikipedia.org/wiki/Nubian_Sandstone_Aquifer_Syste...

If that's really the case, pumping it out sounds like a fool's errand, because it'll just run out. Either that or it's so vast that consumption by millions of people doesn't make a dent in the overall water level.

Cyclical changes in Earth's rotation pushes the North African Monsoon up to the Sahara for a few thousand years every 20k years or so. During this period, the area is much wetter, and over millions of years, very large amounts of water have been deposited in all the areas from where groundwater doesn't drain away.

The source of water for the GMMR is the Nubian Sandstone Aquifer System, which has an estimated 150,000 km³ of water in it, of which 2.4 km³ is pumped out every year.

Re: Great Man-Made River

#40

Post by Naga »

cookiengineer wrote: post #7

I am always amazed by human engineering. I grew up near the Rhine in Germany, and literally they changed the position of the whole river into a different shape, depth, and form so that ships can flow on it. The planning of the event was called "Rheinbegradigung" [1] and they made the river straight, with lots and lots of watergates in between from the Ocean right up to Basel in Switzerland. Eversince I grew up, hundr…

An older, maybe more impressive example (just because of the age of it, or maybe because of my interest in it) is the hydrological systems built in Rome itself. I'll have to dig out the book I read this out of, but there is some evidence that a large part of what was the Forum was man made and made of infill, with the Cloaca Maxima [1] (which is still around and working) built to attempt to manage flooding from the Tiber. The Tiber is a silt heavy river, and the sewers requried pretty constant maintenance.

When the Cloaca Maxima was blocked with silt sometime int he early Middle Ages, the Forum began flooding again and ended up buried by modern times under a significant amount of soil. See pictures [2] and [3] of the same structure from (a painting) in the 1800s and modern day after the excavation. It really shows the power of nature and the success of engineering.

[1] https://en.wikipedia.org/wiki/Cloaca_Maxima [2] Before: https://upload.wikimedia.org/wikipedia/commons/a/a0/Canalett... [3] https://upload.wikimedia.org/wikipedia/commons/thumb/3/38/Ro...

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