Self-cleaning Wet Wells for Constant-speed Pumps

A proposed alternative design for self-cleaning wet wells for constant-speed pumps is described. By using the approach sewer for the part of the station's storage requirement, the wet well can be small. The wet well floor can be configured so that the pumps are used for cleaning without the need for deeper excavation. The alternative design appeared to pose some risks, such as the entrapment and unstable conditions, so the Environmental Protection Agency and several pump manufacturers funded a model study to provide more definitive guidance to design engineers. Laboratory studies and field experience have demonstrated the viability and value of the self-cleaning wet well design in more than 50 pumping stations.