#sluice__sluiceway__penstock  conduit that carries a rapid flow of water controlled by a sluicegate
  supertype:  #conduit__channel  a passage for water (or other fluids)
  part:  #sluicegate__sluice_valve__floodgate__penstock__head_gate__water_gate__watergate  regulator consisting of a valve or gate that controls the rate of water flow through a sluice

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