The Mississippi River ... Just as Christmas, Mardi Gras and Easter roll around annually, so does the mat sinking season with the U.S. Army Corps of Engineers, Vicksburg District.
Each August, an army of men and women, well over 300, begin four months on the Mississippi River in an annual struggle to maintain the riverbanks for levee protection and to provide a safe navigation channel.
Mat sinking is not an 8-to-5 job, but rather seasonal work conducted during the traditional low water months of August, September, October, and November. Low water on the river, primarily, determines when the mat season will begin.
When the workers leave Vicksburg on the quarter boats, compared by some to a large, floating hotel, a season of 10- hour shifts and 12-consecutive-day-work periods begin.
The four gantry cranes move the 16-block sections of mat from the supply barge across to the matboat where workers, using a pneumatic "mat-tying" tool, wire the sections together and to 3/8-inch launching cables running lengthwise between sections.
Normally, the 4- by-25-foot sections are tied together to make a square (1 00 square feet), and 35 squares go together to form a launch. Each supply barge holds 585 squares of mat, consisting of 950 tons of concrete.
The crew hooks the mat cables to dozers (tractors) waiting on shore and the work barge inches away from shore, along the mooring barge, which is 400 by 45 feet, or 100 feet longer than a football field, to launch the concrete "carpet," thus covering 300 to 600 feet of the long sloping river banks. The entire plant moves upstream 130 feet and begins the first launch of a new channel mat.
The crew and matboat are in place when the mooring barge is perpendicular to the shore and the matboat is parallel to the shore and secured to the mooring barge. The articulated concrete mattress (ACM) arrives on location by barge from one of the mat casting fields along the river in Tennessee, Mississippi, and Louisiana.
A fleet of 46 mat supply barges, part loaded and on location and part empty and waiting to be loaded by the mat loading crew at the casting field, is towed up and down the river by Corps or contract boats. On the location, a mat supply barge is moored to the matboat and the mat laying operation begins.
The mat sinking crew lives and dines on the quarter boats that tie off to the bank near the work area. In fact, many of the crew members love the river life so much they work season after season laying mat on the mighty Mississippi.
Although it's hard work, the galley cooks provide 3 exceptional meals a day to accommodate the hungry workers. The two large dining rooms are designed to feed a crew of over 200, who must eat and be back at work within an hour.
Some of the seasonal professions represented on the mat sinking crew include clerks, deck hands, drag line operators, electricians, gantry crane operators, mechanics, quarter boat utility operators, stewards, surveyors, tying tool operators and repairers, tractor drivers, truck drivers and winchmen.
These men and women, although seasonal, perform one of the most important jobs in the Corps of Engineers river stabilization program.
The mat forms a protective overcoat to shield the riverbank from erosion and sloughing caused by channel currents and turbulent water associated with river flood stages.