This pant is operated by the U.S. Army Corp of Engineers. The rows seen are stackes of articulated mattressing. This is used for erosion control along the banks of the river and is installed like a giant carpet from barges. The concrete sections are connected with stainless steel cables making the sections somewhat flexible. This allows the sections to conform to the bank and river bottom shape. The usually extend from the high water mark on the riverbank to the center of the the river channel and are usually found on outside bends where bank erosion is more likely to occur
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