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

The area behind the cofferdam swarmed with men and machines, all raising individual clouds of dust.

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