effluent vs flowage

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. 

flowage

noun
  • A flowing or overflowing of liquid. 

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