The Civil Engineering Contractor November 2018 | Page 19

Construction of the US government-owned Hoover Dam
commenced in 1931 at a cost in today’s exchange rate
of USD650-million. It was built at the height of the Great
Depression. The concrete gravity-arch dam impounds
the Black Canyon of the Colorado River and turned the
American Southwest (along with its scores of smaller
cousin dams) from an arid desert to what it is today:
an urban jungle typified by Las Vegas. The wall is 374m
at its crest, 14m wide at the crest, and 200m wide at
the base. This holds back 2.5m 3 (surface area: 640km 2 )
of the mighty Colorado River’s volume, with a spillway
capacity of 11 000m 3 through two controlled drum-
gates. The dammed water is named Lake Meade with a
catchment area of 435 000m 2 — the largest reservoir in
the US when full.
The power station component generates an installed
capacity of 2 080MW. Its construction was the result of a
massive effort involving thousands of workers, and cost
over one hundred lives. Originally known as Boulder Dam
from 1933, it was officially renamed Hoover Dam for the
nn
then-President Herbert Hoover in 1947.
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