The Gulf Intracoastal Waterway (GIWW) West Closure Complex is designed to reduce risk for residences and businesses in Jefferson and Plaquemines Parishes.
From a storm surge resulting from a tropical event with an intensity that has a one percent chance of occurring annually.Located on the Westbank of the Mississippi River, the complex will consist of a navigable floodgate, a pumping station, floodwalls, sluice gates, foreshore protection, and an earthen levee. The closure structure is located approximately 4,200 feet south of the confluence of the Algiers and Harvey Canals, North of the Hero Canal. Access to the site is from Walker Road via Highway 23 on land and the GIWW on water.The team achieved major accomplishments on this project, the most significant of which was the speed of construction. Award of this contract occurred in April of 2009, with notice to proceed in August of the same year. Twenty-two months later, interim protection was met in time for the beginning of hurricane season which started on June 1, 2011. Construction occurred at an unprecedented rate of approximately $44 million per month, putting into place approximately 90 percent of the $937 million of construction.
Other accomplishments included successful execution of the Early Contractor Involvement (ECI) design assist process and an outstanding safety record, all while maintaining the highest standards of quality.The closure complex consists of the construction of a new 225-foot sector gate, a closure wall, and a 20,000-cubic-feet-per-second pumping station. In addition, this alignment involves construction of a floodwall along the Section 404(c) wetlands area and a flow control structure across the Estelle discharge canal to tie into the Westwego to Harvey levee system.
The alignment also involves construction of levees to tie into the existing hurricane protection system on the East side of the GIWW.Finally, dredging will be required of the Algiers Canal from Highway 23 to the Hero Cutoff to channel flow of the pump station, and will also be required in and along the GIWW to provide safe and continuous navigation of the approach channels to the sector gates.