15 Mile Sink Hole
15 Mile Sewer Repair
3 Access Shafts
10 ft. Diameter X 70' Deep
Cored through existing 11ft. diameter tunnel.
This allowed for temporary pumping of sewage to ground level around the collapsed portion of tunnel.
Used to construct a semi-tangent wall.
This included placing an I-beam in the center for rigidity and allowing the internal bracing support.
Once the necessary bracings were installed, the tunneling contractor open cut down to the tunnel for repair.