rill vs waterway

rill

noun
  • A very small brook; a streamlet; a creek, rivulet. 

verb
  • To trickle, pour, or run like a small stream. 

waterway

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

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

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