Mississippi River & Tributaries, Old River Low Sill Structure (ORLLS) - Dewatering, Concordia Parish, Louisiana

The work consists of fabricating steel cofferdams, delivering to the site and installing cofferdams, unwatering, cleaning concrete surfaces; performing engineering inspection of the gate bays including inspecting and repairing damaged gate rails; lowering Government provided boring rig and ancillary items including leveling platforms into unwatered gate bay monoliths; maintaining the area of each gate bay in a dry condition throughout the unwatered period; fabricate the steel components including arms, struts, anchorages; install anchorages into existing concrete slabs and piers; install monitoring equipment and monitor the structure during the entire unwatering operation; removal of the fabricated cofferdam and anchorages, including transport to the storage location, and unloaded for permanent storage; constructing roadway access from the highway to water’s edge; seeding; placing geotextile, clearing and grubbing, traffic control and coordination, and painting. NAICS code: 237990.