What is water Channelization?
“Channelization is the practice of dredging and straightening stream channels to increase flow rates and carrying capacities. Channelization acts to force as much water as possible away from an area in a short period of time.”- Metropolitan Sewer Division of Louisville
Water channelization is largely done for human convenience rather than as a way of helping the environment. While the idea of channelization is positive, its real-world outcomes say otherwise.
The Negatives of Channelization
“As channelization increases streambank erosion, more sediment enters and clogs the stream, while the accelerated velocity of water increases flooding downstream. In addition, channelization reduces the amount of vegetation along the streambank, which means less food and cover for wildlife.
… The best course of action is to let the stream follow its normal path. Streambank erosion is an inevitable process, but by letting the stream meander naturally, at least the process will be a slow one. With channelization, it can take only 10 years for streambank erosion to do the amount of damage it might have taken 100 years to do naturally.” 1
-University of Illinois College of Agriculture, Consumer, and Environmental Sciences
River: Clear Creek, Iowa, USA
This river was channelized in the 1930′s, and the video shows the effects that the channelization had on the environment.
There were plans to restore a section of clear creek [that had been channelized] and the project would have restored the native infiltration that was originally naturally found in the creek and aided in water flow, and aided in the natural hydrology of the area. The project was terminated in 2015.
http://www2.mvr.usace.army.mil/projects/pubFactsheet/ClearCreekandIowaRiverSection206ProjectJohnsonCountyIowa.pdf
Metropolitan Sewer District of Louisville
http://www.msdlouky.org/index.html
University of Illinois College of Agriculture, Consumer, and Environmental Sciences
http://www.thisland.illinois.edu/60ways/60ways_25.html
