cofferdam

American  

[kaw-fer-dam, kof-er-] / ˈkɔ fərˌdæm, ˈkɒf ər- /

noun

1. a watertight enclosure placed or constructed in waterlogged soil or under water and pumped dry so that construction or repairs can proceed under normal conditions.

2. Nautical. a sealed void between two bulkheads, as for insulation or as an extra barrier to the escape of liquids or vapors.

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cofferdam British  

/ ˈkɒfəˌdæm /

noun

1. a watertight structure, usually of sheet piling, that encloses an area under water, pumped dry to enable construction work to be carried out. Below a certain depth a caisson is required

2. (on a ship) a compartment separating two bulkheads or floors, as for insulation or to serve as a barrier against the escape of gas or oil

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Etymology

Origin of cofferdam

First recorded in 1730–40; coffer + dam ¹

Example Sentences

That included the construction of a huge temporary cofferdam to divert the thundering water from the building site.

From Washington Post • Oct. 6, 2022

Some 27,000 tons of rock and earth were dumped upstream to create a 600-foot long cofferdam from the mainland to Goat Island.

From Slate • May 20, 2019

The exercise began with its easiest assignment - mapping the underwater remains of the steel cofferdam where Broadwater and other archaeologists excavated the wreck of the British supply ship Betsy in the 1980s.

From Washington Times • Nov. 4, 2018

When the waters finally rose in February 1969, water seeping beneath the cofferdam overwhelmed pumps installed to drain it — exactly as predicted by geologist Fryxell.

From Seattle Times • Nov. 22, 2017

A large cofferdam, made of sheets of steel, was being built on the west side of the river to divert the water away from the base of the cliffs there.

From "The Boys in the Boat: Nine Americans and Their Epic Quest for Gold at the 1936 Berlin Olympics" by Daniel James Brown