cofferdam

1 9.9

A strong wall that keeps water out so workers can build below the water level

noun
/ˈkɔfərˌdæm/

Specialized

: taponera

build a cofferdam

Examples

With my heart racing and under a light rain, I climb up the Pimental cofferdam, together with the indigenous warriors who are writing their own history here.

Blog text (17)
The construction crew set up a cofferdam to keep the water out while they repaired the bridge's foundation.
As they prepared to work below the waterline, the engineers realized that a cofferdam would be necessary for the project.
The workers drained the water from inside the cofferdam before starting the underwater construction tasks.

Synonyms

caisson

vscofferdam

Specialized

1 9.6

A large watertight chamber that lets workers build under water

is a more general watertight enclosure used to allow below waterline work

pneumatic caisson

vscofferdam

Specialized

9.8

A large watertight chamber filled with compressed air to keep water out while people work underwater

is not pressurized and instead encloses the work area without compressed air

How Effective

cofferdam

Specialized

1 9.9

retaining wall

Specialized

5 4.4

sheet pile

Specialized

7.4

sheath pile

Specialized

9.9

sandbag

33 2.9

Surface Forms

cofferdam singular

cofferdams plural

Morphology

cofferdam = coffer + dam (semi-transparent) = coffer + dam

Formed as a compound of 'coffer' and 'dam' whose literal meanings suggest an enclosure, but the specialised engineering sense is not immediately predictable for an average learner.

Etymology

Cofferdam comes from two parts: coffer meaning 'box' and dam meaning 'barrier' or 'to hold back water'. So a cofferdam is like a strong box or barrier put in water to keep a work area dry while builders pump out the water and work on foundations.