ASME-Landmark:A.B. Wood Screw Pump


In the early 20th century, New Orleans, with its water table several feet below ground level, faced a crisis after every heavy rainfall—not just through the flooding that continues to imperil the city today, but also through yellow fever, malaria, and other disease caused by impure water. Drainage in New Orleans meant lifting every inch of rainfall out of the city mechanically and lifting it over protective levees—a process that was never successful until the screw pump was developed by A. Baldwin Wood (1879-1956) in 1912.

Wood, a young assistant city engineer, designed and installed a system of large screw pumps (axial flow machines) to syphon water and accelerate drainage. The Wood Screw Pump, which is still used in the city, consists of a syphon in the summit. Inside the syphon is a steel bladed rotating impeller. The casing is split horizontally to facilitate access to the interior of the pump, and the pumps were placed at the top of a pipe syphon that had pipe connections to the suction and discharge canals without the intervention of valves or gates. Priming was accomplished by means of rotary vacuum pumps. By admitting air to the casing before stopping the pump, the vacuum was broken and the water was prevented from syphoning back into the suction basin.

By 1915 the Wood screw pump became the most advanced drainage pump in use. After their successful operation in New Orleans, Wood's pumps were built in the Netherlands, Egypt, China, and India. Wood also redesigned Chicago's drainage system. See ASME website for more information