#waterway  a navigable body of water
  supertype:  body_of_water__water  the part of the earth's surface covered with water (such as a river or lake or ocean); "they invaded our territorial waters"; "they were sitting by the water's edge"
  subtype:  ditch.waterway  any small natural waterway
  subtype:  mare_clausum  (closed sea) a navigable body of water under the jurisdiction of a single nation
  subtype:  mare_liberum  (free sea) a navigable body of water to which all nations have equal access
  subtype:  rapid  a part of a river where the current is very fast

No statement uses or specializes waterway; click here to add one.