Mat Sinking Unit completes the 2020 season March 17, 2021, by Zlatan Hrvacevic The U.S. Army Corps of Engineers, Vicksburg District’s Mat Sinking Unit completed its 2020 revetment season March 4. The Mat Sinking Unit placed approximately 266,000 squares of articulated concrete squares, also known as revetment, along the Mississippi River before its return to the Vicksburg Harbor on March 6 after 230 days of deployment, the second longest deployment in 25 years. Combined, the mats would cover roughly 600 acres. In contrast, over 167,000 squares were placed during last year’s season before early termination due to high water conditions. Revetment prevents riverbank erosion, protects flood control structures and provides reliable waterways for commercial navigation.