Great Man-Made River

Re:Great Man-Made River by Viker on Wednesday March 10, 2021 @04:48AM (#26409569)

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. Eventually when the section completed they would just open the road as a public highway. This really helped Libya build up reach and infrastructure. The truck lines were endless... We are talking km long here...

Eventually when the water reached the coast, I remember I was in Benghazi then. It was good and drinkable from the spring ( this is usually not possible since the water is still salty from the sea) after about a week the sweet water stopped because they started mixing it with the old supply to conserve the desert supplies, the water amount in the desert was over estimated...

All in all Libya was a great country. My family moved to Europe and I remember how much miss information there was about Libya. Then 2012 happened...

Ama about the GMMR. I ll try to answer as best as I can and remember.

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Re:Great Man-Made River by lsmurray on Wednesday March 10, 2021 @05:46AM (#26409929)

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.

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Re:Great Man-Made River by Viker on Wednesday March 10, 2021 @07:54AM (#26410723)

I think the water supply ran out..

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Re:Great Man-Made River by Tuna-Fish on Wednesday March 10, 2021 @11:08AM (#26412698)

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...

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Re:Great Man-Made River by lqet on Wednesday March 10, 2021 @05:46AM (#26409923)

> this is usually not possible since the water is still salty from the sea

Excuse my naive question, but where did the population get drinking water from prior to the GMMR?

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Re:Great Man-Made River by Viker on Wednesday March 10, 2021 @07:52AM (#26410712)

Depends where in the country you are.. Parts of the coast in Libya is really harsh and desert. Mountain parts from Benghazi and eastward and Tripoli and westward. There are some small springs around also, water wells can be dug in various places.

But when the urbanization really started I think most water for the big cities came from salt water processing plants.

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Re:Great Man-Made River by einpoklum on Wednesday March 10, 2021 @05:46AM (#26409925)

1. How come so much water collects in the desert, rather than closer to the coastline?

2. Is there some decent English text, in a book or online, which describes how Libyan society worked up until 2012? With focus on social and political structures and their interaction?

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Re:Great Man-Made River by adolph on Wednesday March 10, 2021 @08:09AM (#26410824)

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...

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Re:Great Man-Made River by einpoklum on Wednesday March 10, 2021 @09:09AM (#26411351)

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.

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Re:Great Man-Made River by Tuna-Fish on Wednesday March 10, 2021 @11:22AM (#26412874)

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.

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Re:Great Man-Made River by azernik on Wednesday March 10, 2021 @09:21AM (#26411483)

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

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Re:Great Man-Made River by weeblewobble on Wednesday March 10, 2021 @12:01PM (#26413415)

I find it very cool that you were there for something like this.

How was it funded? Seems very expensive.

Were regular people excited about it? Was there a meaningful change in day to day life after it was completed?

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Re:Great Man-Made River by hutzlibu on Wednesday March 10, 2021 @09:17PM (#26419389)

"How was it funded? Seems very expensive."

Oil money.

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Re:Great Man-Made River by octocop on Wednesday March 10, 2021 @10:17AM (#26412083)

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

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