pour down on vs swamp

pour down on

swamp

verb
  • To overwhelm; to make too busy, or overrun the capacity of. 

  • To plunge into difficulties and perils; to overwhelm; to ruin; to wreck. 

  • To drench or fill with water. 

noun
  • A piece of wet, spongy land; low ground saturated with water; soft, wet ground which may have a growth of certain kinds of trees, but is unfit for agricultural or pastoral purposes. 

  • A place or situation that is foul or where progress is difficult. 

  • A type of wetland that stretches for vast distances, and is home to many creatures which have adapted specifically to that environment. 

How often have the words pour down on and swamp occurred in a corpus of books? (source: Google Ngram Viewer )