Or take the Aswan High Dam in Egypt, an unmitigated disaster, according to ecologists.

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Jelal is a Nubian, one of the people who lived in southernmost Egypt and northern Sudan until the 1960s, when the Aswan High Dam flooded their land.

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The historical Nubian Temples campaign, for the protection of the Egyptian monuments in Nubia from the rising waters of the Aswan High Dam, mobilized the international community for the protection of the World Heritage.

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They added that since the completion of the Aswan High Dam, Egypt's population had doubled, calorie intake and meat consumption had risen by more than a third, and the use of fertilisers had increased four-fold.

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The Aswan high dam, for example, is often cited as a cautionary example, a quixotic construction that now reduces the mighty Nile to a dribble before it trickles to the sea, leaving behind an explosion of water hyacinth, outbreaks of bilharzia, polluted irrigation channels and a build-up of sediment inland that would otherwise compensate for coastal erosion from Egypt to Lebanon.

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