Cofferdam during construction using a floating crane system to lift the bags in place.
Dominion Divers has been involved in the design and installation of cofferdams of all shapes, sizes, and configurations over our nearly 60 years in the marine contracting business.
The temporary dewatering of a work area can come with many challenges, based on factors such as: area and water depth, geographic location and accessibility, availability of materials, and environmental concerns.
This project took place in a remote, environmentally sensitive location with winter road and fly-in access only. The irregular bedrock of the water passage precluded the use of sheet piling. Additionally, there was no place to stage a crane and no way to mobilize a heavy barge.
Dive inspection of the liner of the cofferdam.
No suitable native materials were available in the area, and there was a strict requirement to minimize turbidity in the fish habitat.
Clean sand, fabric bags, material for a membrane and a lightweight barge with a gantry system for placing the bags were all mobilized to site during the winter and stockpiled to await the open water construction season.
Work crews were flown into the site during the longest days of the summer to build the structure while living in a tent camp on a rocky beach. After work in the water passage was complete the cofferdam was removed with minimal cleanup and impact to the environment.