Kosi River

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The Koshi River or Kośi River, is a transboundary river between Nepal and India and is one of the largest tributaries of the Ganga. The river along with its tributaries, drains a total area of 69,300 sqkm up to its confluence with the Ganga in India (29,400sqkm in Tibet, 30,700 km² in Nepal and 9,200 sqkm in India), a part of Tibet (China) including the Mount Everest region as well as the eastern one third of Nepal.The river basin is surrounded by the ridges separating it from the Brahmaputrain the north, the Gandaki in the west, Mahananda in the east and by the Ganga in the south. The river is joined by major tributaries, approximately 48 km north of the Indo-Nepal border, breaking into more than twelve distinct channels with shifting courses due to flooding.[1][2]Kamlā, Bāghmati (Kareh) and Budhi Gandak are major tributaries of Koshi in India, besides minor tributaries like Bhutahi Balān.^[1][2] Over the last 250 years, the Koshi River has shifted over 120 km from east to west.^[3] and the unstable nature of the river is attributed to the heavy silt which it carries during the monsoon season. Flooding in India has extreme effects. India is second in the world after Bangladesh in deaths due to flooding, accounting for one fifth of global flooding deaths. The Koshi River (The Sorrow of Bihar) is one of two major tributaries, the other river being Gandak, draining the plains of north Bihar, the most flood-prone area of India^[4] Formerly Kauśiki (named after sage Viśvāmitra because Viśvāmitra is said to have attained the status of Vedic ṛṣi or Rishi on its banks; Viśvāmitra was descendant of sage Kuśika and was called Kauśika in Rgveda), in Nepal and Bihar in northern India is a major tributary of the Ganges River (one major tributary of Koshi is Arun which has major part of its journey in Tibet ). This river is mentioned in the epic Mahabharata as Kauśiki. Seven Koshis join together to form the Saptakoshi River which is popularly known as the Koshi.

It is also the life line of the Mithila region, today spread over more than half of Bihar state of India, and parts of adjoining Nepal and forms the basis of legend and folklore of the region; legend of Mithila extends over many centuries. Mithila is also the name of a style of Hindu art created in the Mithila area.

Contents 1 Access to the Basin 2 Geography 3 National parks and fauna 4 Floods of Kosi River - The Sorrow of Bihar 5 Glaciers, Glacier lakes and GLOF 6 Development scenario 7 Adventure Sports 8 Books with Koshi as Folklore 9 Notes 10 External links 11 Reference books

[edit] Access to the Basin

From Katmandu, there is a road for some distance followed by trekking paths to Mt Everest, which crosses four major tributaries of Koshi. Nāmche Bāzār near Tibet border in Nepal (near southern base camp of Mt Everest) is the major tourist centre in the mountaineous part of Koshi belt. Birātnagar in Nepal, and Purnia and Katihār in India are major cities in Koshi Plains. Kamlā, Bāghmati (Kareh) and Budhi Gandak are major tributaries of Koshi in India, besides minor tributaries like Bhutahi Balān.

[edit] Geography

In Nepal the Koshi lies to the west of Kanchenjunga. It has seven major tributaries: Sun Koshi, Tama Koshi or Tamba Koshi, Dudh Koshi, Indravati, Likhu, Arun and Tamore or Tamar. Dudh Koshi joins the Sun Koshi at the Nepalese village of Harkapur. At Triveni Sun Koshi is joined by Arun and Tamar, after which the river is called Sapta Koshi. At Barāhkṣetra in Nepal, it descends from the mountains and it is then called simply Koshi. These tributaries encircle Mt Everest from all sides and are fed by world's highest glaciers. Further down the Triveni, the river cuts a deep gorge across the lesser Himalayan range of Mahabharat Lekh in a length of 10 km and debouches into the plains near Chatra. After flowing for another 58 km, it enters the north Bihar plains near Bhimnagar and after another 260 km, flows into the Ganga near Kursela.(1). The river travels a distance of 729 km from its source to the confluence with the Ganga.

The Koshi river fan located in the northern part of India (in north east Bihar or eastern Mithila) is one of the largest alluvial cones built by any river in the world. This 180 km long and 150 km wide alluvial cone shows evidence of lateral shift exceeding 120 km during the past 250 years through more than 12 distinct channels.The river which used to flow near Purnea in the 18th century now flows west of Saharsa (1). The Koshi alluvial cone and its adjoining area has been studied in detail by remote sensing techniques. The data have been integrated with the available geological and geophysical information to decipher the causes responsible for the lateral shift of such a high magnitude fan. A satellite image shows the old palaeo-channels of the Koshi river with its former (prior to 1731) confluence with the Mahananda River north of Lava.^[5]

[edit] National parks and fauna

There are two famous national parks in the Kosi river basin; the Sagarmatha National Park, located in eastern Nepal, containing parts of the Himalayas and the southern half of Mount Everest and the Koshi Tappu Wildlife Reserve situated on the flood plains of the Sapta-Koshi River in Eastern Nepal.

Sagarmatha National park

Sagarmatha National park is located in eastern Nepal, including parts of the Himalayas and the southern half of Mount Everest. The park was created in July 19, 1976. Sagarmatha in Sanskrit means "mother of the universe" and is the modern Nepali name for Mount Everest. The park covers an area of 1,148 km² and ranges in elevation from its lowest point of 2,845 m at Jorsalle to 8,848 m at the summit of Mount Everest (highest peak in the world).^[6] Other peaks above 6,000m are Lhotse, Cho-Oyu, Thamserku, Nuptse, Amadablam, and Pumori. The upper watershed of the Dudh Kosi river basin system lies in the park. The types of plants and animals that are found in the park depend on the altitude.

The forests provide habitat to at least 118 species of birds, including Danphe, Blood pheasant, Red-billed chough, and yellow-billed chough. Sagarmatha National Park is also home to a number of rare species, including musk deer, wild yak, snow leopard, Himalayan black bear and red panda. Besides, many other animals such as Himalayan thars, deer, langur monkeys, hares, mountain foxes, martens, and Himalayan wolves are found in the park.

In the lower forested zone, birch, juniper, blue pines, firs, bamboo and rhododendron grow. Above this zone, all vegetation are found to be dwarf or shrubs. As the altitude increases, plant life is restricted to lichens and mosses. Plants cease to grow at about 5,750 m, in the permanent snow line in the Himalayas.

The park's visitor centre is located at the top of a hill in Namche Bazaar, also where a company of the Nepal Royal Army is stationed for protecting the park. The park's southern entrance is a few hundred metres north of Mondzo at 2,835 m (9,300 ft), a one day hike from Lukla.

The presence of the Sherpas, with their unique culture, adds further interest to this park.^[7] UNESCO listed the park as a World Heritage Site in 1979 for its unique natural, cultural and landscape characteristics.^[8]

Koshi Tappu Wildlife reserve

Koshi Tappu Wildlife reserve is a wetland situated in the flood plains of the Sapta-Koshi River in Eastern Terai of Nepal. Gazette notified as a wild life reserve in 1976, it covers a reserve area 175 km² and is one of the Outstanding Important Bird Areas in the Indo-Gangetic grasslands. The park has large population of Swamp Francolin, breeding Bristled Grass-warbler, records of White-throated Bushchat and Finn’s Weaver.^[9] The Koshi river forms the major landmark of the reserve and is home to 80 fish species, around 441 species of birds, 30 shore birds, 114 water birds, 20 ducks and 2 ibises. The endangered swamp partridge and Bengal florican are also found here. The Koshi Barrage is an extremely important resting-place for migratory birds (87 nos winter visitors). In view of its rich biodiversity it has been declared a Ramsar site of international significance in 1987.^[10] The endangered Gharial crocodile and Gangetic dolphin locally known as sons in Bihar, endangered specie (fresh water dolphin) have been recorded in the river.

The last surviving population of wild buffalo or arna in Nepal is found in the reserve (number at present is estimated to be 150. The reserve is a habitat of 20 other animal species such as hog deer, spotted deer, wild boar, blue bull and rock python.

The vegetation mainly includes tall khar-pater grasslands with a few patches of khair-sissoo scrub forest and deciduous mixed riverine forest.

During the monsoon, the reserve is flooded with depths ranging from 10 to 300 cm. Bird watching along the eastern embankment at dusk and dawn is one of the most exciting tourist attractions in the reserve.^[11] Gangetic River Dolphin, locally known as sons in Bihar, is an endangered specie (fresh water dolphin).^[12]

[edit] Floods of Kosi River - The Sorrow of Bihar

Koshi or Milk River is known as the “Sorrow of Bihar” when it flows from Nepal to India, as it has caused widespread human suffering in the past due to flooding and very frequent change in course [2] [3] [4].

Koshi has an average water flow (discharge) of 1564 cumecs (cubic metres per second) or 55,000 cubic feet per second (cusecs). During peak floods, it increases to about 18 times over. The highest flood recorded in living memory in the river is reported to be 24,200 cumecs (8,50,000 cusecs) on August 24, 1954 and the Kosi Barrage has been designed for a peak flood of 27,014 cumecs (950,000 cusecs)(2).

Due to extensive soil erosion and land slides in its upper catchment by factors both natural and human, the silt yield of Kosi is about 19 cum/ha/year, one of the highest in the world. (2). The Arun, with its origins in Tibet, brings the greatest amount of coarse silt in proportion to its total sediment load. On account of the steep slopes and narrow gorges in the upper reaches of the river in Nepal, sediment/silt in the river is carried to the plains where the slopes are flatter beyond Chatra resulting in deposition of sediment bed load and high aggradation of the river bed causing a number of interlacing channels, which shift their channels laterally from time to time. The excessive rains, large flood discharge during the monsoon and erosion prone low banks in the plains compound the problem of floods in the highly braided river in the plains of Nepal and north Bihar, inducing pendulum action starting at the bends and triggering extensive damages to life and property in the thickly populated lower plains of the river basin in Nepal and Bihar (more so in Bihar), which has resulted in the river getting the epithet of “River of Sorrow”.{3)

[edit] Glaciers, Glacier lakes and GLOF

^[13].^[14]

At present, in the Himalayan region, glaciers are retreating resulting in formation of glaciers lakes. When such ephemeral lakes burst causing Glacier lake outburst floods (GLOF) in the river, communication systems and various infrastructures like bridges roads, hydropower projects (directly or indirectly), etc are disrupted or damaged or destroyed. Such floods also transport huge amount of sediment.

In the past two decades, Glacial Lake Outburst Flood (GLOF) has become an topic of intense discussion within the development community in Nepal view of the recorded GLOF events which have created havoc in the river system endangering life of thousands of people, hundreds of villages, and basic infrastructure such as trails and bridges and also posing impediments to hydroelectric development in several river basins.

Considering the seriousness of GLOF events, studies of the glaciers and glacier lakes were carried out in 1988 by a joint Sino-Nepalese team. In Arun Kosi river basin, there are 737 glaciers in Tibet and 229 glacier lakes, out of which glacier lakes 24 are potentially dangerous. Similarly, there are 45 glacier lakes in the Sun-Kosi basin out of which 10 are potentially dangerous.

The Dig Tsho glacier lake outburst flood (GLOF) on August 4, 1985, completely destroyed the nearly completed Namche hydropower plant and also all the bridges, trails, cultivation fields, houses, livestock along its path to the confluence of the Dudh-Kosi and the Sun-Kosi rivers at a distance of 90 km from the Dig Tsho glacier. The Dig Tsho glacier is on the terminus of the Langmoche Glacier. This event brought into limelight the seriousness of such events and the studies to assess the glaciers, glacier lakes and GLOF followed.

According to Sino-Nepal study, since the nineteen forties, there have been at least 10 cases of glacier lake outbursts within the basins investigated. Among them there have been five bursts in three glacier lakes of the Arun River Basin, and four in three glacier lakes of the Sun Kosi River Basin.

As a result of above reported catstrophic GLOF, Nepal has instituted studies of snow and ice primarily concerned with the glaciological problems arising in the Himalayas to promote sustainable economic and social development of our country.

[edit] Development scenario

Multipurpose projects

After India attained independence in August, 1947 development scenario in India has been resolute on technological development. In keeping with this approach, the National Flood Control Policy in 1954 (following the disastrous floods of 1954 in large part of the Koshi river basin) stated that floods could be controlled through a series of flood protection works like dams, embankments and river training works. One such work which drew the immediate attention of the policy planners after independence was a solution to the recurring flood menace faced by people of North Bihar due to the Koshi and other rivers, flowing from Nepal to India. The Koshi project was thus conceptualized (based on investigations between 1946 to 1955), in three continuous inter-linked stages – the first was a barrage to anchor this wayward river that had migrated about 120 km westward in the last 250 years laying waste to a huge tract in north Bihar and to provide irrigation and power benefits to Nepal and India. The second part was to build embankments both below and above the barrage so as to jacket the river within the defined channel. The third part envisaged a high multipurpose dam within Nepal at Barakshetra to provide substantial flood cushion along with large irrigation and power benefits to both countries. This was followed up by signing of the Kosi Agreement between Nepal and India on 25 April 1954 and which was revised on 19 December 1966 to address the concerns of Nepal. Further letters of Exchange to the Agreement between the two countries provided for additional schemes for providing benefits of irrigation. While the first two parts of the concept plan have been implemented at the cost of the Government of India, the third part, viz., the Koshi High dam, the kingpin of the whole concept, for various political reasons precluded any action for several years but has since been revived under a fresh agreement, in a modified form for further investigations and studies. (1,2,3,4 & 5)

Details of the above projects are elaborated below.

Kosi barrage and irrigation(4&5)

Kosi Barrage, also called Bhimnagar Barrage after the name of the place where it was built between the years 1959 and 1963 straddles the Indo-Nepal border, in Nepal. It is Irrigation, Flood control and Hydropower generation project on the Kosi river built under a bilateral agreement between Nepal and India: the entire cost of the project was borne by India The catchment area of the river is 61,788 km² in Nepal at the Barrage site. The highest peaks – the Mount Everest and the Mount Kanchenjunga - lie in its catchment. About 10% of this catchment is snow fed. The Eastern Canal and the Western Canal taking off from the barrage have been designed for a discharge capacity of 455 cumecs to irrigate 612,500 ha and 210 cumecs to irrigate 356,610 ha respectively. A Hydropower plant has been built on the Eastern Canal, at a canal drop (3.6 km from the Kosi Barrage), to generate 20 MW. The Western Kosi Canal provides irrigation to 25,000 ha in Nepal. A valuable bridge over the barrage opened up the East-West highway in the eastern sector of Nepal

An Inundation Canal taking off at Chatra, where the Kosi debauches into the plains, has been built to irrigate a gross area of 86,000 ha in Nepal. The project has been renovated with IDA assistance after Nepal took over the project in 1976.

Kosi embankment system (4&5)

The Kosi barrage with earth dams across river, afflux bunds and embankments above and below the river confines the river to flow within embankments.Embankments on both sides downstream of the Barrage with a length of 246 km has been constructed to check the westward movement of the river.The embankments have been kept wide apart, about 12 to 16 km, to serve as a silt trap

Sapta Kosi High Multipurpose Project (Indo-Nepal)

Government of India (GOI) and His Majesty's Government of Nepal (HMGN), have agreed to conduct joint investigations and other studies for the preparation of Detailed Project Report (DPR) of Sapta Kosi High Dam Multipurpose Project and Sun Kosi Storage-cum-Diversion Scheme to meet the objectives of both the countries for Development of a) Hydro Power Generation, b) Irrigation, c) Flood Control/ management and d) Navigation.

A 269 meter high concrete/Rock fill dam on the Sapta Kosi River with a dam toe underground power house with an installed capacity of 3000 MW at 50% load factor, a barrage on river Sapta Kosi about 8 km downstream of Sapta Kosi High Dam to re-regulate the water being released from the Sapta Kosi dam with two canals, Eastern Chhatra Canal and Western Chhatra Canal, off-taking from the either bank from barrage site to provide water for irrigation both in Nepal and India and Navigation through Kosi up to Kursela and also in the reservoir of Sapta Kosi dam are envisaged.

A Power Canal off-taking from the Eastern Chatra Canal is proposed for conveying the water required for irrigation at existing Kosi barrage at Hanuman Nagar and also the water which may be required downstream of Hanuman Nagar Barrage for the purpose of navigation. To utilize the head available between Chatra and Hanuman Nagar barrages for power generation, three canal Power Houses, each of 100 MW installed capacity are also proposed on power canal.

Necessary cushion in storage capacity of Sapta Kosi High Dam would be provided to moderate the flood downstream of dam.

Chatra Canal System would provide irrigation to large areas in Nepal and India (particularly in Bihar).

A Joint Project Office (JPO) has been set up in Nepal for investigation of the project.^[15]

Hydropower

Nepal has a total estimated potential of 83,290 MW out of which economically exploitable potential is 42,140 MW. The Kosi river basin contibutes 22,350 MW of this potential.(360 MW from small chames and 1875 MW from major schemes) and the economically exploitable potential is assessd as 10,860 MW (includes the Sapta Kosi Multipurpose Project [3300MW] mentioned above). The other major projects listed are 1)ArunHEP.^[16]

[edit] Adventure Sports

River rafting

River rafting, also known as White Water Rafting, is a sport that challenges one’s ability to stir against the current of rivers. This is usually done on whitewater or different degrees of rough water, in order to thrill and excite the raft passengers. The development of this activity as a leisure sport has become popular since the mid 1970s. Rafting is the third most popular adventure sport in Nepal; the first is mountaineering, and second is trekking. All these forms of sports exist in the Kosi basin with Mount Everest, the highest peak in the world, offering the best of mountaineering anywhere in the world and the Sun Kosi river (also called river of gold) presenting the longest river trip in Nepal traversing 270 km in length meandering its way through the lovely and picturesque Mahabharata range of mountains. The river rafting trip in the Sun Kosi is listed as one of the world’s top ten classic river journeys. Other rivers where this adventure sport is a popular tourist attraction in Nepal are the Kali Gandaki, the Trisuli, the Bhote Kosi, the Marsyangdi and the Karnali.^[17] and ^[18]

A classic multi-day River trip (9 days) with around 40 rapids of grade 2-5 (Rivers are graded on a scale from one to six based on rapids and difficulties in rafting through the river) is recommended for advance Rafters and Kayakers.^[19]

[edit] Books with Koshi as Folklore

• 
  Balanak Bonihar O Pallavi^[20] - Maithili Short Story collection on the village life of Mithila on the banks of the koshi and its tributaries.1994.Bhubaneswar. By Binod Bihari Verma.^[21]

[edit] Notes

1. ^ Koshi River. Encyclopedia. Retrieved on 2007-08-24.
2. ^ Koshi River, Bihar, India. The Geospacial Research Portal - Natural Hazard Management. Retrieved on 2007-08-24.
3. ^ The Sorrow Of Bihar: Koshi River. Nepalnews.com. Retrieved on 2007-08-24.
4. ^ GIS in Flood Hazard Mapping: a case study of Koshi River Basin, India. Retrieved on 2007-08-24.
5. ^ Abstract Agarwal, R. P. and Bhoj R. (1992) "Evolution of Koshi river fan, India: structural implications and geomorphic significance" International journal of remote sensing 13(10): pp. 1891-1901;
6. ^ Sagarmatha National park - Background
7. ^ Sagarmatha National Park - UNESCO World Heritage Centre
8. ^ Sagarmatha National park - Background
9. ^ http://www.birdlife.org/action/science/species/asia_strategy/pdf_downloads/grasslandsGO2.pdf.
10. ^ http://www.south-asia.com/dnpwc/other-national-parks/koshi-tappu.htm and Gangetic River Dolphin (Platanista gangetica)- Rapidly diminishing
11. ^ Koshi Tappu Wildlife Reserve
12. ^ Gangetic River Dolphin (Platanista gangetica)- Rapidly diminishing [1]
13. ^ South Asian Media Net > OPINION
14. ^ Media For Freedom - news, articles and views e-magazine
15. ^ C:\Documents and Settings\Owner\Desktop\Ministry of Water Resources.htm
16. ^ Nepalnews.com Mercantile Connumications Pvt. Ltd
17. ^ http://www.infohub.com/vacation_packages/11199.html.
18. ^ Rafting Activity in Nepal from nepalvista.com
19. ^ Sunkoshi River Rafting, Nepal Sunkoshi River, Sunkoshi River, Sunkoshi River Rafting in Nepal, Nepal Rafting Agents, Rafting Association in Nepal, Nepal Rafting Association, Rafting in Nepal, Nepal Raft, Nepal Raft Agents, Raft Agents in Nepal, Nepal Rafting Agencies,Nepal Rafting, Adventure Rafting Nepal, Nepal Adventure Rafting, Seti River Rafting, Trishuli River Rafting, Kali Gandaki Rafting, Sun Koshi Rafting, Karnali, Bheri, Tamur and Arun Rivers, White Water Rafting in Nepal, Marshangdi River Rafting
20. ^ Balanak Bonihar o Pallavi
21. ^ Varma, Vinoda Bihari (1994) Balanaka bonihara o Pallavi, tatha anya katha Maithili Pratibha, Bhuvanesvara

[edit] External links

• GIS in Flood Hazard Mapping: a case study of koshi River Basin, India

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[edit] Reference books

1. India's Water Wealth (1975, Dr. K.L.Rao, Orient Longman Ltd, Hyderabad, New Delhi.

2. "Waters of Hope" (1993), B.G.Vargehese, New Delhi 3. Floods, Flood plains and Environmental Myths – State of Art of India’s Environment – A Citizens’ Report, Centre for Science and Environment, 807, Vishal Bhavavn, 95, Nehru Place, New Delhi - 110019.

4. A Framework for Sustainable Development of the Ganges- Brahmaputra- Meghna (GBM Region), Proceedings of Conference held in Dhaka, 4-5 December 1999–Nepal Water Vision in the GBM Regional Framework, Institute for Integrated Studies, Kathmandu).

4. Water Conflicts in South Asia, Managing Water Resources Disputes Within and Between Countries of the Region (2004), Published by GEE-21Honolulu Hi 96825-0517,USA.

5. Barrages in India (1981), Publication number 148, Central Board of Irrigation and Power, Malcha Marg, Chanakyapuri, New Delhi.

6. Design and Construction of selected Barrages in India (1981), Publication number 149, Central Board of Irrigation and Power, Malcha Marg, Chanakyapuri, New Delhi.