Dams: A General Overview
Since time immemorial man has been working his brains out to find means of maintaining a healthy system of water management. As is known to the world, water is an important natural resource we cannot live without. In fact, it’s even impossible to imagine a time of severe water shortage. We very well know of the havoc wrecked during conditions of drought. Keeping all this in mind, an effective system to maintain the usage and sustenance of water became a necessity that in turn led to the discovery of huge barrier walls that controlled the flow of water, dams.
Thus, dams are massive barriers built across streams and rivers to confine and utilize the flow of water for human purposes. They help in providing a permanent supply of water for various uses. In ancient times, dams were built for the sole purpose of helping in the effective water supply for irrigation. But today situation has undergone a massive change that dams aid not only in irrigation but also a multitude of purposes, the primary use being the generation of hydroelectricity.
Impact on the surrounding environment:
However advantageous maybe the construction of dams, necessary precautions ought to be taken to prevent dams from posing a threat to live in the nearby environment. Shifts in the levels of water can result in massive floods leading to death and irreparable damages to surroundings. An irregular flow is very dangerous to fish, and even the wildlife in the area can be threatened. All this calls for taking strict and appropriate measures in dam construction in a way that the surroundings remain unaffected by sudden shifts and changes in water levels.
Given below is a list of some of the major dams in India that have played and is still helping in a productive use of water resources:
1. TEHRI DAM: Situated on the Bhagirathi River in Uttaranchal, the Tehri Dam is the highest dam in India. The dam walls are at a height of 261 meters from sea level. It is also the eighth tallest dam in the world. The high rock and earth-fill embankment were a measure adopted in the construction of the Tehri Dam, the first phase of which was completed in 2006. The water generated from the dam is used mainly irrigation purposes, municipal water supply and for the production of 1000 MW of hydroelectricity.
2. TUNGABHADRA DAM: Located near Hospet in Karnataka, the Tungabhadra dam built across the Tungabhadra River has attracted tourist attention since its completion in 1953. It was constructed as a multipurpose dam serving the needs of irrigation, electricity generation, flood control, and many other environment-friendly projects. When its construction began, it was a project joint venture of the erstwhile Hyderabad state and Madras Presidency. Today the dam has risen to the heights of fame with the innumerable power projects it is supporting and also because Hampi, the city f ancient temple ruins lies in its vicinity.
3. BHAKRA NANGAL DAM: Built across the Sutlej River in Himachal Pradesh, Bhakra Nangal is the largest dam in India. With a height of 225 meters, it is also the second largest dam in Asia. The dam stands testimony to the progress in India’s growth. It was only more than right for Pundit Jawaharlal Nehru to call Bhakra Nangal “The Temple of Resurgent India.” Though the dam is popular as Bhakra-Nangal, it should, however, be noted that both Bhakra and Nangal are two separate dams. The place is worth visiting as you also get to catch a glimpse of the beautiful Aravalli and Shivalik hills surrounding the dam.
4. NAGARJUNA SAGAR DAM: Nagarjuna Sagar is certainly the pride of India and is renowned all over the world as the world’s largest and tallest masonry dam. The dam is built across the Krishna River in Andhra Pradesh. We, as Indians should be filled with pride for being citizens of a country that is host to the world’s largest man-made lake in the world. This colossal dam supplies water necessary for irrigation purposes to the nearby district of Nalgonda and Guntur. The construction of the dam was completed in 1960 and has a height of 124 meters. Also popular as the dam with 26 crest gates, Nagarjuna Sagar is a symbol of modern India’s giant architectural and technological leap.
5. HIRAKUD DAM: Known as the longest dam in India, the Hirakud dam is built across the Mahanadi River located in the tribal state of Odisha. Covering about 26 km in length the dam was the first post-independence multipurpose river valley project in India. The Hirakud Dam is a composite structure of the earth, concrete, and masonry. Gandhi Minar and Nehru Minar are two observation towers on the dam from where you can check the changes in the flow of running water. The dam was built for keeping a check on floods, promoting irrigation and for generating hydroelectricity.
6. SARDAR SAROVAR DAM: Also known as the Narmada Dam, Sardar Sarovar is the largest dam to be built in India. The dam stands tall at a height of 163 meters above sea level. Built over the Sacred Narmada River in Gujarat, water from the dam is used for irrigation purposes in drought prone areas of Kutch and Saurashtra. The gravity dam is also a part of a large hydraulic engineering project that falls under the Narmada Valley project. Sardar Sarovar was constructed for the main purpose of benefitting four states of India namely Gujarat, Maharashtra, Rajasthan and Madhya Pradesh. Repeated pleadings to the Central Government has finally nodded to the proposal of raising the dam’s height from 121.9 meters to 138.7 meters making it the second highest dam in the world at Grand Coulee, U.S.
7. METTUR DAM: Mettur Dam was constructed in 1934 and is located in Tamil Nadu. It was constructed in a gorge where the River Kaveri enters the plains. The dam is popular all over India as it is one of largest as well as the oldest dam to be built in India. It had an installed capacity of 32 MW and had recently hit the news with its opening in August that benefited almost 12 districts of Tamil Nadu. The dam is also credited with the biggest and the most power generating in Tamil Nadu.