Burst pipe

Causes[edit]

Freezing is the classic cause. Water expands as it freezes, and a plug of ice in a pipe raises pressure in the trapped water beyond it; the pipe or a fitting fails, and the escape usually becomes apparent on thawing rather than while frozen. Pipes in lofts, unheated outbuildings, external walls and underfloor voids are the usual sites, which is why insulation and routing are treated as regulatory matters.^[1]

Other causes are mechanical damage from excavation or fixings driven into a wall or floor, corrosion that has thinned a pipe to the point of failure, ground movement imposing load on a buried pipe, and pressure surge.

Immediate response and detection[edit]

The first action is isolation at the internal stopcock, and at the external stopcock if the failure is on the buried supply pipe. Detection is rarely the difficulty on an internal burst; on a buried supply pipe it can be, because a large escape may surface some distance from the failure or not surface at all, following the pipe trench or a service duct instead.

Where a burst on a buried pipe does not show at the surface, the same methods used for smaller leaks apply, and a large escape is generally easier to hear than a pinhole.

Responsibility[edit]

As with any leak on a service pipe, responsibility follows the vesting boundary: the supply pipe is the part of the service pipe not vested in the water undertaker,^[2] and a burst on that length is the property owner's. Continuing loss can also engage section 75 of the Water Industry Act 1991, which deals with waste, misuse and contamination of water.^[3] ADI Leak Detection states that it repairs water mains and plumbing leaks as well as locating them.^[4]