cable tray vs waterway

cable tray

noun
  • A rigid structure to support electric cables; a type of raceway, normally having the appearance of a ladder and open at the top to facilitate changes. 

waterway

noun
  • A conduit or watercourse, such as on the deck of a ship, to drain water. 

  • A body of water, such as a river, channel or canal, that is navigable. 

How often have the words cable tray and waterway occurred in a corpus of books? (source: Google Ngram Viewer )