Revetment operations are primarily the preparation for, and placement of articulated concrete mattress (ACM) from the water's edge, out to design limits in conjunction with stone paving, from water's edge to top bank; which stabilizes the river bank and maintains the proper navigation channel alignment. This operation is normally done from mid-July through mid-November (during low water) and involves men and equipment from Cairo, IL to below New Orleans, Louisiana, on the Mississippi River and along the Atchafalaya River. The Memphis District provides for clearing of the banks, grading of the banks, ACM loading from the mat casting fields, and a portion of motor vessel towing of the barges is ACM. Vicksburg District places the ACM and private contractors provide the stone placement which is called "upper bank paving."
The Memphis District's inner unit of the Bank Grading Unit, clearing and snagging, is the first field activity of Revetment Operations. It begins work on or about July 1st, clearing the riverbanks of trees and debris to make way for the Bank Graders and ACM Sinking unit (of Vicksburg District). The work is accomplished with the use of a barge mounted dragline and bulldozers. Where grading is required, the bank grading party moves in next (about two weeks later) to prepare the riverbank to the design grade and elevation to accommodate the ACM and upper bank paving. the equipment used is a vintage 1949 barge mounted Bucyrus-Erie dragline with a 183 ft. boom and a 15 cubic yard bucket. Additional earthmoving capacity is provided by a compliment of bulldozers. Bedding material (crushed stone) is also placed by this party using a barge mounted dragline with a 100 foot boom with a clamshell bucket. All equipment is moved by towboats up and down the river to the appropriate locations for work.
The Memphis District ACM Loading Unit goes into action about two weeks prior to Vicksburg District's ACM Sinking Plant, which begins work on about August 1st (the low water season). The Memphis District equipment is moved by water to one of the ACM casting fields located adjacent to the Mississippi River in Tennessee, Arkansas, Mississippi or Louisiana. The ACM is loaded onto trucks and hauled to the river bank. There the ACM is loaded onto barges and then placed in tow to the sinking plant.