Natural

Natural river corridors manage floods, slow surface water movement and promote groundwater recharge in a multitude of ways. Many of these strategies have been adapted by engineers when attempting to mitigate flood waters in urban areas. Imagine canyon walls serving as armored channels or a rocky river bottom acting much like riffles and checks in an engineered river channel. Below, there are a number of nondesigned precedents, which help illustrate the ways in which natural rivers function when left to their own devices.

(Left) By Yinan Chen (www.goodfreephotos.com (gallery, image)) [Public Domain], via Wikimedia Commons
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(Bottom Right) By Yinan Chen (www.goodfreephotos.com (gallery, image)) [Public Domain], via Wikimedia Commons

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