Q 01/05

Which type of dam relies on its own sheer weight to hold back the water?

A) Gravity dam

B) Buttress dam

C) Cofferdam

D) Arch dam

Answer · why

A) Gravity dam

The other main types are embankment dams built of earth and rock, buttress dams propped from behind, and arch dams that push the load into the valley ...

Q 02/05

An arch dam is curved in which direction?

A) Downstream, away from the water

B) Sideways along the valley

C) Upstream, into the reservoir

D) It is straight in plan but curved in cross-section

Answer · why

C) Upstream, into the reservoir

The water pressure pushes on the convex face and squeezes the arch into its abutments, which is why the type suits narrow rock gorges and needs far le...

Q 03/05

The Jawa Dam, one of the earliest dams known, was built around 3000 BCE in which modern country?

A) Egypt

B) Iran

C) Jordan

D) Iraq

Answer · why

C) Jordan

The Hittites followed with dams in Anatolia between the 17th and 13th centuries BCE, and the Romans began masonry gravity dams in the 1st century CE.

Q 04/05

The Sadd el-Kafara, the oldest major dam in the world, was built near Cairo by which civilisation?

A) The Roman engineers

B) The Persian kings

C) The ancient Egyptians

D) The Nabataeans

Answer · why

C) The ancient Egyptians

Its name means 'Dam of the Infidels'; it was never finished and was destroyed by a flood because it had no spillway.

Q 05/05

Roughly what share of the world's arable land is irrigated with water from reservoirs behind dams?

A) About 5%

B) About 20%

C) About 40%

D) About 60%

Answer · why

B) About 20%

Irrigation, hydropower, water supply, flood control, navigation and fish farming are the main jobs dams do.