#watercourse.conduit__waterway  a conduit through which water flows
  supertype:  conduit__channel  a passage for water (or other fluids)
  subtype:  flume  watercourse that consists of an open artificial chute filled with water for power or for carrying logs
  subtype:  headrace  a waterway that feeds water to a mill or water wheel or turbine
  subtype:  tailrace  a watercourse that carries water away from a mill or water wheel or turbine

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