Mechanical Options

Mechanical options refer to methods used to mechanically open the Kaitorete Barrier to allow the Lake to drain to the sea.  These opening options are linked to a specific opening trigger Lake level.  Mechanical opening have been the prefered option of opening the lake.

  • prior to 1868: local Maori were know to have let the lake out to protect the Pa at Taumutu by using various escavation methods
  • 1868 to 1904, 1925-1931:  use of horse drawn scoops 
  • 1931: Ellesmere Drainage Board purchased power scoops
  • 1947: North Canterbury Catchment Board took responsibility using bulldozers and draglines.
  • Currently: Environment Canterbury is responsible for the opening using hydraulic excavators