catchment area vs coulee

catchment area

noun
  • An area from which water drains into a particular lake, river, etc.; the catchment area of a large river includes its tributaries. 

  • The area served by a local institution, such as a hospital or school, or by extension, a railway station. 

coulee

noun
  • A stream. 

  • A lava flow. 

  • A deep gulch or ravine, frequently dry in summer. 

  • A reach of water in a bayou that is like a slough but deeper. 

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