Underwater Tunnel Rehabilitation with Patented Diver Operated Vehicle

Safety, quality, and value were key drivers for the solutions-oriented project team when evaluating the rehabilitation of two 70–90-year-old concrete lined raw water tunnels experiencing distress and cracking. An “in-the-wet repair” solution, without interruption to the water supply, was developed to re-line the tunnels with custom stainless-steel inserts to extend the service life of the facility. Assembled by divers at the invert of the tunnel, the liner inserts would be transported over 700 ft down the tunnel for installation by a diver-operated transporter vehicle, integrating an electric over hydraulic power system. The transporter has two onboard underwater monitors and eight LED lights allowing divers to navigate the 25-ft-long transporter down the tunnel with a load capacity of just over 9,000 pounds.