Importance of Dam, Types and Most Important Dams of India

A dam is a barrier that is usually built across a river, a stream, or an estuary to retain water and the purpose to build a dam is to provide water for irrigating, Hydroelectric power plants, human daily uses, or for use in industrial processes. The dam is also used to reduce peak discharge of floodwater created by large storms or snowmelt, sometimes by operating the water level of dams, its helps to increase the water depth of a river in order to improve navigation by which ships can travel more easily. To generating hydroelectric power, dams are used to increase the amount of water available. The Ancient old dam in the world is located in the Black Desert, at Jawa of Jordan.

According to structure and intended purpose, some of the important types of dams are given below:

1. Buttress Dam: This type of dam was originally built to retain water for irrigation or mining. This type of structure is made of reinforced concrete and is supported on the downstream side by a series of buttresses or supports which are placed at certain intervals. The wall of this type of dam is straight or curved in shape. The pressure of the water pushes against the dam, but the buttresses are inflexible and in this way, it helps to prevent the dam from falling over. This type of concept introduces from the Roman period, they use this type of dam to increase the stability of a dam wall. In the early 20th Century, Buttress dams of slab concrete construction became popular in the United States.

2. Coffer Dam: To create a dry working environment within a water body (i.e. River, ocean, etc) so that the work can be carried out safely, this kind of dam is generally built within the body of water. For the repair or construction of dams, bridges, piers, etc., this type of dam is needed. Cofferdams are a welded steel structures, with components consisting of cross braces, sheet piles, and wales. Such structures are usually separated into pieces after the construction work is completed.

3. Diversion Dam: This type of dam diverts a certain part of the flowing watercourse or entire water flow to a different path so that the water can be diverted into an artificial watercourse or canal, which may be used for irrigation or return to the river after passing through hydroelectric generators, or form an artificial on-ground or groundwater reservoir. This type of concept was seen around 2600 BC, in the Egyptian Sadd el-Kafara Dam at Wadi Al-Garawi, which was located near Cairo.  

4. Overflow Dam: Usually to raising the water level of the river’s course, this type of dam is constructed, it also permits the overflow of water during the passage of excess (flash-flood) discharges over the entire length of the dam or through some drain openings.  

5. Regulating Dam: This type of dam constructed in a topographically low area on the perimeter of a reservoir, required to contain the reservoir from which water is released to regulate the flow downstream

6. Saddle Dam: This type of dam was constructed in a topographically low area on the perimeter of a reservoir, required to contain the reservoir at the highest water surface elevation.  

Some of the Major Dams of India

Dam Name	Location	River	Notes
Kallanai Dam	Thanjavur district of Tamil Nadu	Kaveri river	It is an example of Barrage Dam and this is the first and fourth oldest water regulator dam in the world.
Tehri Dam	Tehri district of Uttarakhand	Bhagirathi river	It is an example of an embankment dam, having a height of 855 ft and a length of 1,886 ft, it becomes the highest dam in India.
Hirakud dam	Sambalpur of Odisha	Mahanadi river	Having 200 ft tall and 55 km long, this is the longest Dam in India, which is fully maintained by the government of Odisha.
Bhakra Nangal Dam	Bilaspur district of Himachal Pradesh	Sutlej river	This is an example of a concrete gravity dam of Himachal Pradesh, besides this, it is the third-largest reservoir in India.
Nagarjuna Sagar Dam	Guntur district of Andhra Pradesh	Krishna river	It is an example of a masonry dam, having a height of 407 ft.
Sardar Sarovar Dam	Navagam district of Gujarat	Narmada River	This is a concrete gravity dam of Sardar Sarovar Narmada Nigam Limited.
Tungabhadra Dam	Bellary district of Karnataka	Tungabhadra River	This is an example of a Composite dam. It is also a famous dam of India, as it was built without concrete and cement.
Rihand Dam	Sonbhadra District of Uttar Pradesh	Rihand river	Having a huge capacity to holding water (10.6 billion cubic meters), it becomes the largest dam in India by volume.
Koyna Dam	Koynanagar of Maharashtra	Koyna river	This is a Rubble-concrete dam in Maharashtra and it is one of the largest dams in Maharashtra.
Ukai Dam	Tapi district of Gujarat	Tapi River	It is the second-largest reservoir in Gujarat and creates the Vallabhsagar reservoir.
Mettur Dam	Salem district of Tamil Nadu	Cauvery (Kaveri) River	This is a Gravity and Masonry dam of Tamil Nadu and it is 214 ft in high.
Indira Sagar Dam	Khandwa district of  Madhya Pradesh	Narmada River	This dam comes under the irrigation system of Madhya Pradesh state. It is the largest dam in India by water capacity.
Jayakwadi Dam	Jayakwadi district of Maharashtra	Godavari river	Having 27 water gates, this is one of the largest dams in India.
Somasila Dam	Nellore District of Andhra Pradesh	Penna River	This dam is an example of an earth-fill dam as well as a gravity dam, which covers an area of 212.28 km.
Ujani Dam	Solapur district of Maharashtra	Bhima river	This dam is an example of a gravity dam having a 185ft high.
Mukkombu Dam	Jeeyapuram village of Tamil Nadu	Kaveri river	Having a height of 685 meters, this is one of the smallest dams in India.
Cheruthoni Dam	Idukki District of Kerala	Periyar River	This is one of the examples of a gravity dam of India, having a height of 453 ft, this gravity dam is the largest in Kerala. It is a part of the Moolamattom Power Station.
Bhavani Sagar dam	Sathyamangalam district of Tamil Nadu	Bhavani River	This is an example of an earth-filled Embankment dam, and it is the largest embankment dam in India and South Asia.
Maithon dam	Maithon of Jharkhand	Barakar River	To control the flood situation, this dam was specially designed and it is a part of an underground power station, which can generate 60,000 kW of electric power. This kind of power station is created for the first time in Asia.
Tilaiya dam	Koderma district of Jharkhand	Barakar River	This dam was created in the first phase of the Damodar Valley Corporation under its multi-purpose dam.