Project Details

The offshore end of the existing outfall was exposed.  It was discovered that the previous contractor had sealed the outfall by filling their excavated trench with concrete, which was not shown on their as-builts.  The existing outfall was cut and chipped using cable saws and divers to permit the installation of the extension. 

The extension consisted of 96m of 710mm HDPE with 15 risers/diffusers and 3 diver-access ports installed inside a steel pipe liner.  Trench excavation and outfall installation was performed from spud barges. The extension was sealed, floated and towed into position, where it was sunk.  Once in place and attached to the existing outfall the entire extension was filled with grout.