What is the straight dope on this? Was it a failure? Should it have been built? I always read things about how it ruined the river economy up north, but didn’t it help more than it hurt?
In this thread I linked to several useful sites, discussing the pros and cons of the Aswan dam. Maybe they will help you.
What are the (dis)advantages of the Aswan Dam?
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For another hot issue covering much the same grounds, check out the proposed “Three Gorges Dam” on the Yangtze River, China.
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The Three Gorges Dam isn’t just proposed, it’s built. They closed the gates and started filling the reservoir behind it a month ago.
But the complete project is not due (fully) for completion until 2007 (or 2009 at current estimates).
The site provided by Aro gives a fair overview of the actual issues, but no basis upon which to judge their weight.
A few years ago, in looking at potential markets for genetically engineered products with salt resistance my former team took a look at Egypt.
The electrification provided by the dam was an immediate boost, the Egyptian government did not use it terribly effectively to jump start an economy – recall that Egypt still suffers from an only partially dismanted quasi-socialist partly state run economy.
Smoothing of water flows and elimination of serious drought threats are positives, but do not necessarily require the single mega dam that is the Aswan High Dam (although it is not as impressive as one might think, visually speaking). A series of dams with lower surface area might have been a better solution, including ones with some provision to preserve some aspects of the floods.
Current problems arising from the Aswan scheme include:
(a) Salting of the soil. Around 40 meters (if I recall correctly the number) down lies massive salt pans from extintc seas. Under the current water regime, which tends to over water due to poor irrigation infrastructure that looses up to 60 percent of transited water through leakage. Rising water tables based on this are causing salt infiltration into the soil, which is not flushed away by the floods, and as noted on the page, not renewed by new silt laydown.
(b) Subsidence of the highly productive Delta, due to lack of renewal and to reduced fresh water flows. Significant losses are occuring along the Med-Basin border.
© Decreased soil productivity tied to (i) salt infiltration (ii) soil exhaustion (iii) inefficient irrigation regimes require ever increasing fertilizer inputs, which is increasing costs overall.
(d) As noted, rising water tables and presence of standing water, tied in part to inefficient water usage, have led to explosions in water borne diseases tied to slow or still waters. Nsty stuff, expensive to fight. Bilharzia e.g. is one nasty disease.
(e) Aswan has locked in a water surplus mentality, however in actual fact current usage rates on a cm/an basis are well above Egypt’s treaty obligations to Sudan, and dangerously dependent on Ethiopian inputs into the hydrolic system.
Aswan, in short, was a prestige project that did not look to the long term. The long term results have been uneven (partly due to governmental corruption and inefficiency that I can report are staggering in Egypt) and the long term effects are probably net negative.