Siphons
Many older dams were not constructed with a means of draining the reservoir. Lowering the reservoir may be needed for temporary construction, for emergency response, or when regular releases aren't needed. Siphons can be a low-cost means of providing a reservoir outlet if one does not exist. The key operational parameters are: (1) the required hydraulic lift cannot exceed the effective local atmospheric pressure adjusted for vapor pressure and frictional losses; (2) the discharge point of the siphon must be lower in elevation than the body of water to be siphoned; and (3) the pipe or hose used for the siphon must be designed to operate at less than atmospheric pressures. Note that siphon outlets can be difficult to prime.
Examples
Get answers to some of the common questions about siphons
Trainings
On-Demand Webinar: Design of Siphon Systems
Citations:
Revision ID: 4813
Revision Date: 12/02/2022