water, water everywhere, but not a drop to drink

Water, water everywhere, but not a drop to drink is an old phrase which comes from an old rhyming song spoken about a mariner who was stuck in the middle of the sea and even though he was surrounded by water, he could not drink it because people cannot drink sea water without becoming sick and dehydrated. The entire rhyme goes water, water, everywhere, nor any drop to drink which was written by Samuel Taylor Coleridge.