Ideal for river control in 

narrow channels; 

seen here at Flatford in Suffolk, England.

Bottom hinge flap or torque gates

These gates are used to control the flow of water in a river. The gate structure incorporates a torque tube along the bottom edge which transfers the water load through to the actuator, this is normally a hydraulic cylinder.

  • Advantages
    • The gate installation is unobtrusive.
    • Torsion tube allows operation from one side.
    • Good overflow discharge characteristics.
  • Disadvantages
    • Limited to short spans due to gate deflection.
    • The actuator is located in a pit alongside the water channel and passes through a seal in the side wall giving additional civil costs.