Transplanting seas to inland ocean lakes? A good idea for the Middle East?
The two century-old and highly respected Japanese engineering giant Shimizu has hatched a wild and crazy proposal to rehabilitate the desert for human use.
Their idea is to move vast amounts of seawater along canals that would track deep into desert landmasses to create a series of connected huge inland seas measuring 30 km (18 miles) across. Small cities could then be created within the gigantic seawater “lakes,” on artificial islands.
Each seawater lake with its city would spaced apart along connecting canals measuring 150 km (93 miles) between each seawater lake city. Compared with most desert cities, in these lake cities, climate would be moderated by the body of water. The differences in thermal mass between sand and sea foster wind and even clouds due to evaporation.
A similarly massive water project initiated by Libya transfers fresh water from a distant underground aquifer. There are real sustainability issues with their plan though, because it is essentially just moving the fresh water storage from its current protected, cool, shaded, underground aquifer outside to swelter in the hot desert sun, where it won’t last as well.
By contrast, this project uses seawater, already on the surface. This is a sustainable supply of water (once developed) since it taps a replenish-able source, the ocean.
To prevent it from soaking down into the sand the water in the lakes would be retained by a continuous, two-meter-thick underground wall that reaches down to the impermeable layer, (presumably protected with rebar against earthquake).
The seawater itself in the lakes could support fish farming, which would bring a source of protein into arid deserts.
Because it is salt water, agricultural applications could use the technology pioneered by the Seawater Greenhouse which utilizes evaporation on the inside of greenhouse roofs to distill freshwater from seawater spray for use in irrigation.
Bio-energy crops could also be grown in the seawater, utilizing new and promising research involving plants that can be grown in salt water.
In exciting new work underwritten by the Masdar Institute with a desert succulent that grows in seawater, an innovative start up, Global Seawater Inc has pioneered raising a hitherto never farmed potential new bio-energy crop: Salicornia.
If cultivated in the permaculture of an interdependent mini ecosystem, Salicornia can make both bio energy and shrimp farms, while also increasing beneficial Mangrove forests, that thrive in seawater.
So, the seawater could support both Seawater Greenhouse agriculture, and energy production, fish farming, and Mangrove reforestation. Not bad! But wait, there’s more:
Between the lake cities would be 10 meter (33 feet) deep canals. At 50 meters across – 150 feet wide – barge traffic would be able to ship goods between cities at a very low carbon cost. Positively utopian!
Image:Shimizu Corporation
Related water stories:
Libya Touts Man-made River as 8th Wonder of the World
Qatar Considering Using Seawater Greenhouses
Yemen Funnels Sea-water to Drinking Water With the Low Tech Watercone
how about the salinity which would constantly increase due to evaporation ? I don’t believe in this. Not realistic
There are also numeous natural depressions in Algeria, Tunesia, Lybia and Egypt under sea level, totalling 10’s of thousands of square miles, you’d need no pump to flood them. There’s a giant valley in Mauritania, surrounded by sahara sand dunes. The Okavango desert, Etosha and Lake Turkana are salt water lakes, we’d boost their size. Also Lake Tsjaad can be filled with fresh water from one of the affluents of the Congo river. We’re talking billions of dollars, but we can use old combat equipment engines as pumps, the Africans are very good at maintaining old engines without access to spare parts.
There’s not much time left, let’s do it.
Permaculture sounds like a much better solution. There are some examples of people who have been recuperating deserts just by builing swales. The scale of ecological manipulation that is demonstrated in this article is nowhere near necessary.
Here is one example of a site that rebuilt a part of Jordan using swales: http://www.blog.thesietch.org/wp-content/permaculture.swf
Don’t think its a good idea. I heard that the islands Dubai made in the ocean cost the earth to keep up (literally) and have also affected the currents. We’re messing with a system that would work perfectly if only we could allow it to do its job.
I hear you. But at least it serves some purpose! (Unlike the artificial islands, which are not needed)
Surely the biggest problem is acumulated sand silting up the canals and ‘lakes’. Solve that problem in a cost efficient manner and you’ll have cracked it.
Hey Susan,
Sewage treatment plants do produce clean water from sewage. They occasionally fail, of course. It may also become possible to capture the nutrients in wastewater for a wastewater to biofuels scheme. There are numerous devils in the details. Those details are painstakingly discussed in:
“http://www.energybiosciencesinstitute.org/media/AlgaeReportFINAL.pdf”
The scale of the petroleum industry is genuinely mind boggling. Even if we operated these sewage to biofuel facilities at their maximum output, globally there would not be enough sewage to replace the petroleum we currently use. This assumes wastes from 6.8 billion people (no animal waste), a replacement target of 74 million barrels of oil per day, algae that produces 30% recoverable oil by dry weight and CO2 supplies that are abundant and free. (I told you that there were numerous devils in the details). Other essential nutrients like phosphate and potassium would quickly turn into environmental restraints. Figuring out how to recycle these is a key problem.
best,
George
Thanks George, yes, I am learning a lot about the waste water innovations in this region since starting to write (and research!) about it. Lot’s of vhttp://www.greenprophet.com/wp-admin/edit-comments.php#comments-formery exciting developments, indeed.
Very interesting article. The last paragraph however contains a minor mistake – 50 meters does not equal “nearly half a mile across”. 50 meters would more likely equal a little more than 50 yards.
In my opinion, what’s needed out in the Sahara and other desert locations are lakes of FRESH WATER and not sea water. The fresh water reservoirs can be created either from desalinated or recycled sewage water. Can you imagine someone who’s lost in the desert approaching one of these salt lakes, thinking the water can be drunk? What a
“basa”!
Maurice, heh: horrible thought! Could that much water be created from recycled sewage water though? This would be on such a gigantic scale.
Thanks Susan for this interesting post.
What if these saltwater towns have terrible wastewater treatment systems, as most Middle Eastern countries do? Won’t that that increase the rate at which the seas/oceans are polluted? Also, if we divert these waters, what are the potential consequences for marine ecosystems and the climate?
That’s your followup story! 🙂