This multiphase secondary treatment plant addition expanded the plant’s existing capacity by 40 million gallons per day (MGD) and extensively modified the existing facility. Successive phases of the project consisted of construction of a new sludge dewatering building; a filtrate pump station; a cast-in-place bridge; an 18,000 sq ft generator building; a 9,000 sq ft blower building; a 372- by 230-foot influent pump station located 105 feet deep in the ground; a 700- by 700-foot, 60-foot-deep peak flow handling facility; and an effluent pump station. The project also included installation of eight 160-foot-diameter primary clarifiers, sixteen 140-foot intermediate clarifiers, aeration basins, final clarifiers, and a gravity deep bed filter as well as modifications to the blower building. The total concrete volume for all phases of the project was nearly 300,000 cubic yards.