The biggest dams in India

Hailed as the "Temples of Resurgent India" by Pandit Jawaharlal Nehru, the country's dams help provide water and electricity to millions citizens. We look at some of the biggest ones.

The Tehri Dam is a multi-purpose rock and earth-fill embankment dam on the Bhagirathi River near Tehri in Uttarakhand, India. It is the primary dam of the Tehri Hydro Development Corporation Ltd. and the Tehri hydroelectric complex. The dam is a 260 metres (850 ft) high rock and earth-fill embankment dam. Its length is 575 metres (1,886 ft), crest width 20 metres (66 ft), and base width 1,128 metres (3,701 ft). [Photo: By Arvind Iyer from Mumbai [CC-BY-SA-2.0 (http://creativecommons.org/licenses/by-sa/2.0)], via Wikimedia Commons}

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Bhakra Dam is a concrete gravity dam across the Sutlej River, and is near the border between Punjab and Himachal Pradesh in northern India. The dam, located at a gorge near the (now submerged) upstream Bhakra village in Bilaspur district of Himachal Pradesh, is Asia's second highest at 225.55 m (740 ft) high next to the 261m Tehri Dam. The length of the dam (measured from the road above it) is 518.25 m; it is 9.1 m broad. Its reservoir, known as the "Gobind Sagar", stores up to 9.34 billion cubic meters of water, enough to drain the whole of Chandigarh, parts of Haryana, Punjab and Delhi.The 90 km long reservoir created by the Bhakra Dam is spread over an area of 168.35 km2. In terms of storage of water, it withholds the second largest reservoir in India, the first being Indira Sagar dam in Madhya Pradesh with capacity of 12.22 billion cu m.Nangal dam is another dam downstream of Bhakra dam. [Photo by KawalSingh at en.wikipedia (Transferred from en.wikipedia - Public domain from Wikimedia Commons]

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Hirakud Dam is built across the Mahanadi River, about 15 km from Sambalpur in the state of Orissa in India. Built in 1957, the dam is one of the world's longest earthen dam. Hirakud Dam is the longest man-made dam in the world, about 16 mi (26 km) in length. It is one of the first major multipurpose river valley project started after India's independence. [Photo by Quarterbacker (Own work) [CC-BY-3.0 (http://creativecommons.org/licenses/by/3.0)], via Wikimedia Commons]

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Nagarjuna Sagar Dam is the world's largest masonry dam built across Krishna River in Nagarjuna Sagar, Nalgonda District of Andhra Pradesh, India, between 1955 and 1967. The dam contains the Nagarjuna Sagar reservoir with a capacity of up to 11,472 million cubic metres. The dam is 490 ft (150 m). tall and 1.6 km long with 26 gates which are 42 ft (13 m). wide and 45 ft (14 m). tall. Nagarjuna Sagar was the earliest in the series of large infrastructure projects initiated for the Green Revolution in India; it also is one of the earliest multi-purpose irrigation and hydro-electric projects in India.

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The Sardar Sarovar Dam is a gravity dam on the Narmada River near Navagam, Gujarat, India. It is the largest dam and part of the Narmada Valley Project, a large hydraulic engineering project involving the construction of a series of large irrigation and hydroelectric multi-purpose dams on the Narmada River. The project took form in 1979 as part of a development scheme to increase irrigation and produce hydroelectricity. It is the 30th largest dams planned on river Narmada, Sardar Sarovar Dam (SSD) is the largest structure to be built. It has a proposed final height of 163 m (535 ft) from foundation. The dam is one of India's most controversial dam projects and its environmental impact and net costs and benefits are widely debated. The World Bank was initially a funder of the SSD, but withdrew in 1994. The Narmada Dam has been the centre of controversy and protest since the late 1980s. [Photo by AceFighter19 (Own work) [Public domain], via Wikimedia Commons]

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The Indirasagar Dam is a multipurpose key project of Madhya Pradesh on the Narmada River at Narmadanagar in the Khandwa district of Madhya Pradesh in India. The Project envisages construction of a 92 m high and 653 m long concrete gravity dam. It provides Irrigation in 1,230 square kilometres of land with annual production of 2700 million units in the districts of Khandwa and Khargone in Madhya Pradesh and power generation of 1000 MW installed capacity (8x125). The reservoir of 12,200,000,000 m3 (9,890,701 acre•ft) was created.

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The Bhavanisagar Dam and Reservoir, also called Lower Bhavani Dam, is located on the Bhavani River between Mettupalayam and Sathyamangalam in Erode District, Tamil Nadu, South India. The dam is situated around 16 km (9.9 mi) west to Satyamangalam and 35 km (22 mi) from Gobichettipalayam, 36 km (22 mi) north-east to Mettuppalayam and 70 km (43 mi) from Erode and 75 km (47 mi) from Coimbatore.

The dam is considered to be among the biggest earthen dams in the country. Bhavani Sagar dam is constructed on Bhavani River, which is merely under the union of Moyar River. The dam is used to divert water to the Lower Bhavani Project Canal.

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The Koyna Hydroelectric Project is the largest completed hydroelectric power plant of India It is a complex project consisting of total four dams with the largest Dam built on Koyna River known as Koyna Dam hence the name Koyna Hydroelectric project. The total Installed capacity of the project is 1,920 MW. The project consists of 4 stages of power generation. Due to the project's electricity generating potential the Koyna River is considered as the life line of Maharashtra.

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The Idukki Dam, located in Kerala, India, is a 168.91 m (554 ft) tall arch dam. The dam stands between the two mountains - Kuravanmala (839) m and Kurathimala (925)m. It was constructed and is owned by the Kerala State Electricity Board. It supports a 780 MW hydroelectric power station.

It is built on the Periyar River, in the ravine between the Kuravan and Kurathi Hills in Kerala, India. At 167.68 metres, it is one of the highest arch dams in Asia and third tallest dam in India.

Photo by http://www.kseb.in/ [CC-BY-SA-2.5-in (http://creativecommons.org/licenses/by-sa/2.5/in/deed.en)], via Wikimedia Commons

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Krishna Raja Sagara, also popularly known as KRS, is the name of both a lake and the dam that causes it.Sir. Mokshagundam Visvesvarayya served as the chief engineer during the construction of this dam. The dam is named for the then ruler of the Mysore Kingdom, Krishnaraja Wodeyar IV [Photo by Amarrg at the English language Wikipedia [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0/)], from Wikimedia Commons] 

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The Mettur Dam is a large dam in India built in 1934.[1] It was constructed in a gorge, where the Kaveri River enters the plains. The dam is one of the oldest in India. The total length of the dam is 1,700 m (5,600 ft). [Photo by Praveen Kumar.R (Own work) [CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons]

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The Srisailam Dam is a dam constructed across the Krishna River at Srisailam in the Kurnool district in the state of Andhra Pradesh in India and is the second largest capacity hydroelectric project in the country. The dam was constructed in a deep gorge in the Nallamala Hills, 300 m (980 ft) above sea level. It is 512 m (1,680 ft) long, 145 m (476 ft) high and has 12 radial crest gates. It has a reservoir of 800 km2 (310 sq mi). [Photo by Chintohere (Own work) [Public domain], via Wikimedia Commons] 

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The Banasura Sagar Dam is located 21 km from Kalpetta, in Wayanad District of Kerala in the Western Ghats. It is the largest earthen dam in India and the second largest in Asia. [Photo by Challiyan (Own work) [CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons]

The Longest River in the World - Nile

The Nile is the longest river in the world, stretching north for approximately 4,000 miles from East Africa to the Mediterranean. Studies have shown that the River (Iteru, meaning, simply, River, as the Map of the Nile RiverEgyptians called it) gradually changed its location and size over millions of years. The Nile flows from the mountains in the south to the Mediterranean in the north. Egyptians traveling to other lands would comment on the "wrong" flow of other rivers. For example, a text of Tuthmosis I in Nubia describes the great Euphrates river as the "inverted water that goes downstream in going upstream."

Three rivers flowed into the Nile from the south and thus served as its sources: the Blue Nile, the White Nile and the Arbara. Within the southern section between Aswan and Khartoum, land which was called Nubia, the River passes through formations of hard igneous rock, resulting in a series of rapids, or cataracts, which form a natural boundary to the south. Between the first and second cataracts lay Lower Nubia, and between the second and sixth cataracts lay upper Nubia.

Along most of its length through Egypt, the Nile has scoured a deep, wide gorge in the desert plateau. At Aswan North of the first cataract the Nile is deeper and its surface smoother. Downstream from Aswan the Nile flows northerly to Armant before taking a sharp bend, called the Qena. From Armant to Hu, the River extends about 180 kilometers and divides the narrow southern valley from the wider northern valley.

Southern Egypt, thus being upstream, is called Upper Egypt, and northern Egypt, being downstream and the Delta, is called Lower Egypt. In addition to the Valley and the Delta, the Nile also divided Egypt into the Eastern and Western Deserts.

The Nile Just South of AswanThe Nile Valley is a canyon running 660 miles long with a floodplain occupying 4,250 square miles. The Delta spans some 8,500 square miles and is fringed in its coastal regions by lagoons, wetlands, lakes and sand dunes.

The Delta represented 63 percent of the inhabited area of Egypt, extending about 200 kilometers from south to north and roughly 400 kilometers from east to west. While today the Nile flows through the Delta in only two principal branches, the Damietta and the Rosetta, in ancient times there were three principal channels, known as the water of Pre, the water of Ptah and the water of Amun. In classical or Graeco-Roman times, these were called the Pelusiac, the Sebennytic, and the Canopic branches. There were additionally subsidiary branches or artificially cut channels.

The most dominant features of the Delta as the sandy mounds of clay and silt that appear as islands rising 1-12 meters above the surrounding area. Since these mounds would not be submerged by the inundation, they were ideal sites for Predynastic and Early Dynastic A modern sailboat on the Nile, with a not so unusual sail settlements, and indeed evidence of human habitation have been found. Perhaps these mounds rising above the water table inspired the ancient belief of creation as having begun on a mound of earth that emerged from the primordial waters of Nun (Pyramid Text 600).

There were several major oases of the Western desert, which comprised about 2/3 of Egypt: the Fayoum, where during the Middle Kingdom period the capital of all Egypt was situated, and which increasingly became one of the most densely populated and agriculturally productive area in Egypt, the Bahriya, where many sarcophagi of the Graeco-Roman period have been found, the so-called Golden Mummies, Kharga and Dakhla, which were known for their excellent wines, and Siwa, whose Oracle of Amun was consulted by Alexander the Great to demonstrate that he was the true successor to the kingship of Egypt.

The Eastern Desert was exploited in Pharaonic times for its rich minerals.

The mere mention of the name of the Nile evokes for modern man images of Pyramids, great temples, fantastic tales of mummies, and wondrous treasures. But the Nile represents life itself to the people of Egypt, ancient and modern. In fact, for thousands of years, the River has made life possible for hundreds of thousands of people and animals, and has shaped the culture we today are only beginning to truly understand.

The River filled all areas of life with symbolism. In religion, for example, the creator sun-god Ra (Re) was believed to be ferried across the sky daily in a boat (compare that to the Greeks and Romans whose non-creator The Nile River God, Hapy (Hapi)sun-god rode across the sky in a chariot driven by fiery horses, and Hymns to Hapy (Hapi), the deity personifying the Nile, praise his bounty and offerings were left to him, and the creation myths, as mentioned earlier, revolve around the primordial mound rising from the floodwaters surrounding it; in ritual where Nile creatures such as the hippopotamus, whose shape the goddess Tawaret took, or the crocodile, called Sobek, or Heket (Heqet), the frog, deities deemed powerful in the processes of childbirth and fertility, were revered, in writing, where floral signs such as the lotus and papyrus figured prominently, in architecture, where the very structure of temples emulated the mounds of the Nile and its waves, from the bottom to the top of capital columns and the trim on walls, and in travel, where models of boats have been found dating from the fifth millennium BCE. and

The god Hapy was earlier mentioned as being the personification of the floods and ensuing fertility. Two Hymns to the Nile, one probably composed in the Middle Kingdom, the second written later in the Ramesside period, praise Hapy and the river for its renewed life for Egypt.

"Hail to you Hapy, Sprung from earth, Come to nourish Egypt Food provider, bounty maker, Who creates all that is good! Conqueror of the Two Lands, He fills the stores, Makes bulge the barns, Gives bounty to the poor." (from the Middle Kingdom hymn as translated by Lichtheim)

From the earliest times, the waters of the Nile, swollen by monsoon rains in Ethiopia, flooded over the surrounding valley every year between June and September of the modern calendar. A nilometer was used to measure the height of the Nile in ancient times. It usually consisted of a series of steps against which the increasing height of the Inundation, as well as the general level of the river, could be measured. Records of the maximum height were kept. Surviving nilometers exist connected with the temples at Philae, on the Nubian Egyptian border, Edfu, Esna, Kom Ombo, and Dendera, as well as the best-known nilometer on the island of Elephantine at Aswan.

The ancient Egyptian calendar, made up of twelve months of 30 days each, was divided into three seasons, based upon the cycles of the Nile. The three seasons were: akhet, Inundation, peret, the growing season, and shemu, the drought or harvest season. During the season of the A Nile Sunset (Photo by Bob Fallon) Inundation, layers of fertile soil were annually deposited on the flood-plain. Chemical analysis has shown how fertile the Nile mud is. It contains about 0.1 percent of combined nitrogen, 0.2 percent of phosphorus anhydrides and 0.6 percent of potassium.

Since most of the Egyptian people worked as farmers, when the Nile was at its highest and they could not plant, they were drafted by corvee into labor projects such as building Pyramids, repairing temples and other monuments and working on the king s tomb.

Herodotus, the great Greek philosopher, wrote of the Nile: "the river rises of itself, waters the fields, and then sinks back again; thereupon each man sows his field and waits for the harvest." The great historian also called Egypt the gift of the Nile. This description would lead the casual reader to imagine Egypt as being a great paradise where the people simply sat and waited for the sowing and harvesting to need be done. But the ancient Egyptians knew better. Too high a flood from their river, and villages would be destroyed; too low a flood, and the land would turn to dust and bring famine. Indeed, one flood in five was either too low or too high.

The rock inscription called the Famine Stela, dated in its present form from the Ptolemaic period, recounts an incident, (whether real or fictitious is not currently known for certain), from the period of King Djoser of the 3rd Dynasty. The King writes to a governor in the south, describing himself as disheartened over the country s seven-year famine. The King learns from a priest of Imhotep that if gifts are given to the temple of Khnum, the creator-god of the region, who it was believed had control over the Nile and its flooding, then the famine would be ended.

"I was in mourning on my throne, Those of the palace were in grief .because Hapy had failed to come in time. In a period of seven years, Grain was scant, Kernels were dried up Every man robbed his twin Children cried The hearts of the old were needy Temples were shut, Shrines covered with dust, Everyone was in distress .I consulted one of the staff of the Ibis, the Chief lector-priest of Imhotep, son of Ptah South-of-the-Wall .He departed, he returned to me quickly, He let me know the flow of Hapy Learn the names of the gods and goddesses of the temple of Khnum: Satis, Anukis, Hapy, Shu, Geb, Nut, Osiris, Horus, Isis, Nepththys As I slept in peace the god stood before me, I propitiated him by adoring him and praying to him. He revealed himself to me with kindly face and said: I am Khnum, your maker! My arms are around you For I am the maker who makes, I am he who made himself, Exalted Nun, who first came forth, Hapy who hurries at will I shall make Hapy gush for you, No year of lack or want anywhere, Plants will grow weighed by their fruit Gone will be the hunger years Egypt s people wil come striding Hearts will be happier than ever before .I made this decree on behalf of my father Khnum In return for what you had done for me all tenants who cultivate the fields their harvests shall be taken to your granary All fishermen, all hunters I extract from them one tenth of the take of all these One shall give the branded animals for all burnt offerings and daily sacrifices, and one shall give one-tenth of gold, ivory, ebony, ochre, carob wood, carnelian, all kinds of timber " (as translated by Lichtheim)

Many modern travelers to Egypt today take a Nile cruise as part of their package. And why not? For to see the land as its people do, one must journey on the river. A felucca is often the water vehicle of choice.

The Nile flowed from south to north at an average speed of about four knots during inundation season. The water level was on average about 25-33 feet deep and navigation was fast. That made a river voyage from Thebes (modern Luxor) north to Memphis (near modern Cairo) lasting approximately two weeks. During the dryer season when the water level was lower, and speed slower, the same trip would last about two months. At the great bend near Qena, the Nile would flow from west to east and then back from east to west, slowing down travel. No sailing was done at night because of the danger of running aground on one of the many sandbank and low islands.

When one cruises on the Nile, one might pass by the ancient and significant sites of Karnak itself, Luxor, on the other side of the river from Karnak, Dendera, with its grand temple to the goddess Hathor, Abydos, with its marvelous temple built by Seti I as well as being the site of Earlier Dynastic tombs, Esna, with its temple to the potter and creator-god Khnum, lord of the region who was credited as having the power over the river and its richness, Edfu, with its temple to Horus, Kom Ombo, with its double temple to Sobek and a form of Horus called Haroeris, and Aswan itself, with its mighty modern dam.

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World's Largest Gorge - The Grand Canyon of the Colorado River

World's Largest Gorge - The Grand Canyon of the Colorado River
The Grand Canyon (Spanish: Gran Cañón) is a steep-sided gorge carved by the Colorado River in the United States in the state of Arizona. It is largely contained within the Grand Canyon National Park, one of the first national parks in the United States. President Theodore Roosevelt was a major proponent of preservation of the Grand Canyon area, and visited it on numerous occasions to hunt and enjoy the scenery.

The Grand Canyon is 277 miles (446 km) long, ranges in width from 4 to 18 miles (6.4 to 29 km) and attains a depth of over a mile (1.83 km) (6000 feet). Nearly two billion years of the Earth's geological history have been exposed as the Colorado River and its tributaries cut their channels through layer after layer of rock while the Colorado Plateau was uplifted. While the specific geologic processes and timing that formed the Grand Canyon are the subject of debate by geologists, recent evidence suggests the Colorado River established its course through the canyon at least 17 million years ago. Since that time, the Colorado River continued to erode and form the canyon to the point we see it as today.

Before European immigration, the area was inhabited by Native Americans who built settlements within the canyon and its many caves. The Pueblo people considered the Grand Canyon ("Ongtupqa" in Hopi language) a holy site and made pilgrimages to it. The first European known to have viewed the Grand Canyon was García López de Cárdenas from Spain, who arrived in 1540.


The Grand Canyon is a massive rift in the Colorado Plateau that exposes uplifted Proterozoic and Paleozoic strata, and is also one of the six distinct physiographic sections of the Colorado Plateau province. It is not the deepest canyon in the world; Kali Gandaki Gorge in Nepal is far deeper, nor the widest (Capertee Valley in Australia is about 1 km wider and longer than Grand Canyon) — but the Grand Canyon is known for its visually overwhelming size and its intricate and colorful landscape. Geologically it is significant because of the thick sequence of ancient rocks that are beautifully preserved and exposed in the walls of the canyon. These rock layers record much of the early geologic history of the North American continent.

Uplift associated with mountain building events later moved these sediments thousands of feet upward and created the Colorado Plateau. The higher elevation has also resulted in greater precipitation in the Colorado River drainage area, but not enough to change the Grand Canyon area from being semi-arid. The uplift of the Colorado Plateau is uneven, and the north-south trending Kaibab Plateau that Grand Canyon bisects is over a thousand feet higher at the North Rim (about 1,000 ft/300 m) than at the South Rim. Almost all runoff from the North Rim (which also gets more rain and snow) flows toward the Grand Canyon, while much of the runoff on the plateau behind the South Rim flows away from the canyon (following the general tilt). The result is deeper and longer tributary washes and canyons on the north side and shorter and steeper side canyons on the south side.

Temperatures on the North Rim are generally lower than the South Rim because of the greater elevation (averaging 8,000 ft/2,438 m above sea level). Heavy rains are common on both rims during the summer months. Access to the North Rim via the primary route leading to the canyon (State Route 67) is limited during the winter season due to road closures. Views from the North Rim tend to give a better impression of the expanse of the canyon than those from the South Rim.

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