Stoplogs are frequently used to temporarily block flow through a spillway or canal to enable dewatering of the area for routine inspection and maintenance of the main equipment. Operation is usually by mobile/gantry crane using fixed slings or an automatic lifting beam. Stoplogs can be single or multiple units dependant upon the size of channel being isolated.


  • Eliminates building and removal of 'coffer dams'.
  • Can be removed from underwater using an automatic lifting beam.
  • Allows maintenance of other gates.
  • Economical, may not be painted.


  • Operation has to be performed in balanced conditions.
  • Requires storage area when not in use.
  • Need to lift plumb.