Water under the bridge describes a past experience, quarrel or mistake that has already happened and cannot be changed, so there is no point letting it continue to affect the present. It is most often used to draw a line under an old disagreement, as a way of saying that whatever went wrong before is now finished and best left alone.
What’s the origin of the phrase ‘water under the bridge’?
The image is straightforward: water that has flowed under a bridge is gone and cannot flow back, so it stands for anything finished and irreversible. This way of putting it is echoed across reference works as a plain metaphor rather than something coined by a particular writer, and no single author is credited with inventing it.
The related expression water over the dam is the older of the two, first recorded in 1797, according to the American Heritage Dictionary of Idioms, which notes that the under the bridge version came later, dating from the late 1800s. An early documented instance of the bridge form appears in the Irish novelist Julia Kavanagh’s 1858 novel Adèle, and the way it is used there suggests the phrase was already established in speech before that date rather than being newly minted for the book.
The same idea turns up in French from around the same period. A proverb dated to the 1840s, il passera bien de l’eau sous le pont, meaning much water will pass under the bridge, uses the identical picture of flowing water marking the passage of time and events. Whether the English and French versions influenced each other or developed independently from the same obvious image is not clear, but their closeness in both wording and timing suggests the metaphor was simply an easy one for people to reach for once bridges over running water were a familiar part of everyday life.
Today the phrase is used almost entirely to describe a past experience someone prefers not to let affect their current life. It is heard constantly in reconciliations and apologies, usually as a signal that someone is choosing to move on rather than keep raking over old grievances.