water over the dam

Idioms and Phrases

Also, water under the bridge . Something that is over and done with, especially an unfortunate occurrence. For example, Last year's problems with delivery are water over the dam , or Never mind that old quarrel; that's water under the bridge . These metaphoric phrases allude to water that has flowed over a spillway or under a bridge and thus is gone forever. The first term was first recorded in 1797; the variant dates from the late 1800s.