What does the word sewer mean?

Usage examples for sewer

  1. No, sir, the old Mississippi ain't much better than a sewer now. – Bolanyo by Opie Percival Read
  2. It is the terminal sewer. – The Glow-Worm and Other Beetles by Jean Henri Fabre
  3. He had reached the mouth of the sewer and was in the river. – The Mad King by Edgar Rice Burroughs