The project provided surge protection as secondary containment to minimize potential levee failures and lowered risk for failure of the Belle Chasse Tunnel. The tunnel is part of the Highway 23 heavy traffic corridor as well as a critical emergency evacuation route. This, along with other USACE projects, combined to replace, raise and/or enhance existing flood protection structures. It also served to complete needed maintenance and repair to the aged 1956 tunnel damaged by previous flooding.

Conti Federal tackled extremely complex project site logistics, including flood walls installed through a railroad crossing, below an active bridge, under high voltage power lines and around a structurally-sensitive tunnel, as well as strict regulations for work on these very active transportation channels. The team constructed three swing and two roller flood gates over the highway, two railroad swing flood gates, reinforced concrete T-walls, concrete I-walls, groundwater relief well systems and road and highway construction. Conti Federal was also responsible for demolition and construction of tunnel approach walls for tie-in to the gate monoliths, railroad track work, installation of 59,000 square feet of steel sheet pile and 37,000 linear feet of H-pile, embankment construction and installation of six temporary retaining structures (TRS) on a design-build basis.

Critical items were long lead relocation of utilities with local entities to ensure project schedule integrity.

Key features of the project included:

  • Worked with active railroad lines
  • Installed 37,000 linear feet of H-piles and 59,000 square feet of steel sheet piles
  • Fabricated and installed of tunnel overhead roller gates, highway and railroad swing gates
  • Maintained traffic control on major transportation artery
  • Performed vertical and road slab wire saw cuts
  • Demolished and constructed a tunnel

The Highlights

37K

Linear Feet

Conti Federal installed 37,000 linear feet of H-pile.

59K

Linear Feet

The team installed 59,000 linear feet of steel sheet pile.

6

TRS

Conti Federal installed six temporary retaining structures (TRS) on a design-build basis.

“Conti’s prep-phase planning meetings are the best seen run by any contractor in New Orleans.”

– USACE Quality Assurance Officer