Photo courtesy of Traylor-Massman-Weeks

Completed in October 2010, the approximately 7,500-ft-long floodwall closes off the Mississippi River Gulf outlet and connects into the Gulf Intracoastal Waterway bypass structure.

The largest design-build civil works construction project in U.S. Army Corps of Engineers history, the Inner Harbor Navigation Canal Surge Barrier in New Orleans is designed to provide a robust and sustainable post-Katrina flood-protection system for the city and surrounding area.

Baton Rouge, La.-based Shaw Environmental & Infrastructure Group coordinated design and construction, awarding the largest portion, the $330-million Inner Harbor Navigation Canal Floodwall, to Evansville, Ind.-based Traylor-Massman-Weeks LLC in May 2009. Ben C. Gerwick Inc., Oakland, Calif. was the structural engineer.

Completed in October 2010, the approximately 7,500-ft-long floodwall closes off the Mississippi River Gulf outlet and connects into the Gulf Intracoastal Waterway bypass structure. The surge barrier forms a dam preventing inland flood progression. When storm waves reach design elevation, they overtop the floodwall, filling the storage basin. Following the storm, floodgates are opened for drainage.

"The floodwall required a design which would be light in construction due to deep deposits of soft and muddy clay along with the incorporation of deep foundation techniques and ease of construction to facilitate aggressive schedule requirements," says Eric D. Effinger, engineer for TMW Inc.

Meeting these challenges, TMW proceeded at 36 ft to 48 ft of wall per day. Moving quickly, the team moved safely as well; for the project's total of 1.05 million man-hours—peaking at 350 workers—no lost days were recorded.

Extensive use of floating equipment was required as well as a custom-engineered, 2,000-ft-long trestle system. Equipment included 16 barge-mounted cranes; five land-based yard cranes; 10 trestle-mounted platforms supporting such equipment as customized pile-driving templates; and more than 40 material barges.

In all, 4,454 piles were used, 26,000 cu yd of pile spoil material removed, 68,000 cu yd of concrete placed, 530,000 cu yd of soil stabilizer injected and 300 cap sections weighing 90 tons each installed.

Key Players

Owner: U.S. Army Corps of Engineers, New Orleans

GC: Traylor-Massman-Weeks, Evansville, Ind.

Construction Manager: Shaw Environmental and Infrastructure, Baton Rouge, La.

Lead Design: Ben C. Gerwick, New Orleans

Submitted by:

Traylor-Massman-Weeks