They diverted the river around them.

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The diverted water then joins the river again through a channel known as a tailrace.

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The flow of the mighty river has been diverted, billions of dollars have already been spent, and the work of moving more than 1m residents from the area is well advanced.

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When Belo gets built, around 20, 000 will have to relocate, hundreds of acres of virgin forest will be flooded, and the Amazon tributary, the Xingu River, will be diverted to feed the turbines that will potentially generate 11, 200 megawatts of electricity if all goes swimmingly well.

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Last month, Highland Council published details on how traffic will be diverted during the first stage of constructing the River Ness Flood Alleviation Scheme.

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Levees along the length of the river appeared to be holding, and water diverted through spillways seemed to be rising more slowly than expected, but Louisiana Gov. Bobby Jindal warned residents that plenty could go wrong.

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