Difference between Dam and Reservoir

Dams and reservoir both are created to control the flow of a river and to store water for irrigation and other purposes. People often confuse a dam with a reservoir as they share some features. Although both are closely related to each other, they are different from each other. Let us see how a dam differs from a reservoir!

Dam:

A Dam is a barrier that is built across a river, stream or estuary to hold back or retain the water. It is made from a variety of materials like steel, rock, and wood. It is primarily used to manage, save and use the water for specific purposes like electricity generation.

Advantages of Dam:

It controls the flow of a river.
It helps build a reservoir.
It stores water for irrigation.
It helps generate electricity from water.
It protects the surrounding areas from flooding.
It creates artificial lakes for swimming, water sports, boating, etc.

Types of Dam:

By structure, a dam can be of four types:

Gravity Dam
Arch Dam
Buttress Dam
Embankment Dam

Famous Dams in the World:

Some of the dams in the world that serve as giant barriers to many rivers are as follows:

Daniel Johnson Dam in Canada
Robert-Bourassa Dam in Canada
Tehri Dam in India
Guri Dam in Venezuela
Kariba Dam in Zimbabwe
Bratsk Dam in Russia

Reservoir:

It is an open-air large water body that looks like an artificial lake or a water reservoir. It is generally formed by building a dam or wall across a river or a broad valley. However, it can also be created by surrounding a piece of land with dikes and then diverting a part of the river flow into that land.

The water stored in a reservoir can be used for multiple purposes like irrigation, hydropower, consumption and domestic use. It is fed by precipitation, rainwater runoff and from the flow of a river.

Types of Reservoirs:

Reservoirs can be of three types:

Valley-dammed reservoir: It is created in valleys where mountainsides are used as the walls of the reservoir, and a dam or artificial wall is built to hold the water.
Bank-side reservoirs: They are formed by diverting water from rivers or streams to an existing reservoir.
Service reservoir: It is a large container that holds clean water. The polluted or contaminated water, which has been treated in a water plant, is stored in a service reservoir before it is supplied to end users.

Based on the above information some of the key differences between dam and reservoir are as follows:

Dam	Reservoir
It is a concrete wall constructed across a river or a valley to control the flow of a river.	It is a human-made large water body that is formed to store the water. It is a part of a dam.
It is made of concrete, steel, etc.	It is made of water that accumulates behind the dam.
It helps create sites for hydroelectric generation.	It is used to provide water for consumption and irrigation.
It is a tourist attraction site. People from different parts of the world travel to different places to see the massive dams.	It is a large water body with huge depth and thus can hold cruise ships and cargo ships. So, it can be used for water transportation by the people of that region.
Types by the structure include gravity dam, arch dam, buttress dam and embankment dam.	Its types include the valley-dammed reservoir, bank-side reservoir and service reservoir.