The purpose of this project was to enlarge and concrete-line the section of Suburban Canal crossing under I-10 in Metairie. The length of the section to be improved was approximately 450 ft.

Traditionally, this type of project would be accomplished by bypassing or rerouting traffic lanes, allowing for the installation of a sheeted cofferdam. The canal could then be de-watered and all work completed in the dry. This method was not available for this project, with the requirement that traffic not be impacted on I-10 at any time.

The result was a design that required us to excavate the project in the wet and install 1,280 helical anchors capped with a concrete panel to stabilize the canal bottom prior to dewatering. Once all the anchor panels were in place and load tested, the canal could be drained and a concrete channel lining placed. All of this had to be accomplished while working under four low bridges for the most part from water.

The project called for exacting tolerances. It was imperative that the canal be excavated to the proper grade and panels placed as specified in order to assure the stability of the canal slopes and bottom when de-watered. A testing program for the anchors was implemented to ensure that each anchor rod was in fact functioning as designed.

Several factors had to be overcome in order to progress in a successful manner. First, Shavers-Whittle had to resolve how to remove more than 4,000 cu. yds. of excavated material from under and between the bridges. They solved this by using sectional barges with a platform built to support an excavator placed between two barges.

The second challenge was to install anchors within inches of a prescribed location in several feet of water from a barge. This was performed the old fashioned way by placing points on the canal banks and using a tape measure. Placing of the concrete panels followed closely behind with the assistance of divers, who guided the panels over the anchors, aligned them with adjacent panels and secured the panels with plate washers and nuts.