Question

what r dams ? mention four advantages and disadvantafes of dams .

Answer 1

Dams refer to massive walls or barriers built specifically to regulate the flow of water or underground streams.
Advantages of Dams:

Helps in flood control.

Hydroelectricity generated by dams is a renewable energy source.

Lakes and reservoirs can help in irrigation.

Provides regular water supply for domestic as well as industrial consumption.

Major tourist draws.

Provides still water habitat for some species.
Disadvantages of Dams:

Highly cost-intensive.

High maintenance costs.

Affects the biodiversity of nearby regions.

Any damage or failure may lead to huge losses.

Leads to destruction of natural environment over a period of time.

Results in altercations between neighboring countries over the flow of water.

Answer 2

Dam is a structure that restricts , retards , conserve excessive amount of water

Its advantages :

It helps to prevent flood

Helps in generating hydro electricity

Industrial purposes

Domestic uses

Irrigation

Navigation

Its disadvantage:

Over sedimentation in bottom of dam

Disects rivers

Change natural flow of rivers

Making difficult for fishes to navigate especially during breeding time

As over sedimentation in dams in case of floods it fails to control flood and breaks due to pressure