Portishead marina in Somerset, England; all M & E and hydraulic engineering
by KGAL.

Sector Gates

These gates are widely used for sea locks at the entrance to marinas where passage through the lock is required under the widest possible tidal range.


  • Can open or close with a full differential head.
  • Operates with water loads from either side.
  • Quick operating, typically 60 secs as the gates move through an arc.
  • Cuts easily through any silting.
  • Curved skin means water loads are transfered directly to the pivot which reduces friction.


  • More complex design of gate structure and sealing.
  • Larger civil works due to side recesses.
  • Curved skin needs an assembly jig.
  • Pivot alignment is critical.