This project featured a 60-foot-diameter sunken caisson pump station, a concrete spillway and an intake structure. The work included rock grouting, rock anchors, pipe jacking, support of excavation pilings, excavation, reinforced concrete, erosion control, storm sewer installation, service roadway construction and landscaping. The finished pump station includes three 4000-GPM high-flow pumps and two 1100-GPM low-flow pumps. The pumps move detention basin water through 24-inch and 20-inch ductile iron process piping. All pumps and valves are managed by a programmable logic controller and variable frequency drives in the structure’s electrical room.