The South Cobb Tunnel, part of the Cobb County Water System (CCWS), collects and treats wastewater for most of the northwest Atlanta, Georgia region. At 8.9km (5.5 mile) in length and 8.2m (27 ft) in diameter, the South Cobb Tunnel is the largest capital improvement project in CCWS history. It is also the deepest tunnel in the Atlanta area, with a maximum depth of 122 m (400 ft). Designed to be partially lined with cast-in-place concrete needed for structural support and/or groundwater control, the tunnel features a 130 million gallons/day lift station to convey wastewater flows from the tunnel to the treatment plant.
PENETRON ADMIX was used to treat over 20,000 cubic yards of concrete.