effluent vs landflood

effluent

noun
  • A stream that flows out, such as from a lake or reservoir; an outflow; effluence. 

  • Sewage water that has been (partially) treated, and is released into a natural body of water; a flow of any liquid waste. 

adj
  • Flowing out; outflowing. 

landflood

noun
  • An overflowing of land by river; an inundation or freshet. 

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