Project Scope
The Detroit Water and Sewerage Department constructed a new treatment facility at the head end of Conner Creek in Detroit, to capture, treat and disinfect Combined Sewage Overflows that are discharged into the Detroit River. The facility encompasses approximately 175,000 square feet above ground and 40,000 square feet below ground.

Project Problem
The staff of the Nautilus Marine Group International was retained to perform all underwater work for the construction of this new facility. The tasks and problems encountered on this facility were vast and varied. From concrete placement to placement of cofferdams and installation of new bulk heads. All work was completed in zero visibility.

Scope of Services
The staff of the Nautilus Marine Group International dive team was comprised of a five-man dive team utilizing two divers, a dive supervisor and two dive technicians as the tender/standby diver. The divers employed surface supplied air diving techniques to support the underwater engineering services. The divers used a helmet mounted underwater video camera to document the current conditions of their work. All diving operations were performed from the ground at the new facility. Several different tasks were completed at the Conner Creek facility. This included placement of stop logs and plugs in the old and new sewer system allowing work to be done in the dry in other sewer tunnels. Several cofferdams were constructed on site and used for sealing off selected sewer tunnel areas for construction work to be completed in the dry. The staff also used their skills in underwater welding and cutting to remove obstruction from the sewer tunnels and placement of new bulk heads. We also completed several concrete placement tasks in sealing the existing sewer tunnel for breaks and cracks.