|- right||Ratua Khola|
|- location||near Dalkhola, Kishanganj district, Bihar, India|
The Kankai is a rainfed perennial river of eastern Nepal. The area has warm temperate rainy climates with mild winters. Upper part of the basin basically consists of granitic gneiss of Cambro-Ordovician age and the lower part consists of Quaternary rocks. The Kankai is gravelly river with more than 60% gravel of gneiss and remaining other are of different metamorphic and sedimentary rocks. The sediment yield of the river is estimated to be 0.148 million ton/year.
The Kankai has a drainage area of 1,148 square kilometres (443 sq mi).
The Kankai irrigation system was developed for the purpose of irrigating 8,000 hectares (20,000 acres) of agricultural land in Jhapa, a Terai district located at the south-eastern corner of Nepal. Its command area is flanked by the Kankai in the east, the Khrisna River in the west, the Mahendra Highway in the north and the Indian border in the south. A detailed feasibility study of the project was completed in 1970 with the technical assistance of ADB. The construction was carried out in two phases. The first phase was initiated in 1973 and completed in 1981 with substantial delays and cost overruns. The second phase, to irrigate an additional 3 000 ha, started in 1980 and was completed in 1991, bringing only 2,000 hectares (4,900 acres) of land under irrigation. Thus irrigation infrastructure has been developed for a total of 7,000 hectares (17,000 acres) of land. The total cost of the project was NRs 310 million, 63 percent of which came from an Asia Development Bank loan.
The canal system consists of a three-tier network of canals. The main canal length is 34 kilometres (21 mi) with 74 kilometres (46 mi) of secondary canals and 110 kilometres (68 mi) of tertiary canals. The first 11.5 kilometres (7.1 mi) reach of the main canal is lined with a design capacity of 10.15 m3/s; the other reaches are unlined and their capacity decreases from 7.25 to 1.75 m3/s.
The density of structures in the system is quite high. The canal network crosses many flashy rivers, hence many cross drain structures (siphons) have been built in the system. Steel gates have been built at all off-take points from the main canal and at all tertiary off-takes from secondary canals. The total number of such regulating structures is 322. Including all other subsidiary hydraulic structures, the structural density is as high as 0.2 per ha.
The command area consists of flat land (average slope of 1/800) with fertile soil. The soil texture varies from loamy to sandy loam. Alluvial soils exist in most parts of the command area. Brown forest soil is found in the northern part of the command while paddy soil exists in the southern parts.
After the completion of the second phase of the project, financial assistance from ADB ceased and in 1993 the Kankai Development Board, formed in 1973 for the implementation of the construction works, was dissolved. Since then, the Kankai irrigation office, under the Department of Irrigation, is responsible for the operation and maintenance of the system.
The Kankai, flowing through the central part of the Jhapa District, is one of the perennial rivers. Erosion of banks and inundation during rains cause problems for the residents of its catchment area near Satasidham and Panchganchi village development committees. The protection works being carried out with Government of India assistance of NRs.2.67 crores will help to control floods and save habitation and valuable agricultural land of over 31,000 people along its banks of the catchment area. The project is being implemented by Department of Water Induced Disaster Prevention, Ministry of Water Resources, Government of Nepal with the participation of local users.
Kankai Multipurpose Project
The Kankai Multipurpose Project is proposed to be located in Jhapa and Ilam districts of Nepal. While the reservoir and its catchment lies in Ilam district, the irrigation command area is in Jhapa district. A net area of 67,450 hectares (166,700 acres) will be irrigated. The projet includes a 38 MW power plant. The project is part of the Kosi-Mechi link. The project has been stalled because of objections from India.
The Kankai River in Jhapa is a famous pilgrimage site. Devotees from various parts of the country and even from India throng the Kankai. People worship this river as Kankai Mai, the goddess Kankai. The western bank of this river is known as Maidhar and the eastern one is known as Kotihom. Kankai Mela, probably the biggest mela of eastern region, is held here every Maghe Sankranti, the first day of the tenth month Magh of the Nepali calendar.
- "Five Themes of Geography". Rivers. Retrieved 2010-05-22.
- "Gurkha War". New World Encyclopaedia. Retrieved 2010-05-22.
- "Kishanganj district". Kishanganj district administration. Retrieved 2010-05-22.
- "Kankai River". india9. Retrieved 2010-05-23.
- UK Raghubanshi. "Font Size: Engineering, hydrological, and sedimentation studies of the Kankai River, eastern Nepal". Journal of Nepal Geological Society, Vol 36 (2007). Retrieved 2010-05-23.
- "An overview of glaciers, glacier retreat and subsequent impacts in Nepal, India and China". WWF. Retrieved 2010-05-23.
- "The modernization efforts of the Kankai irrigation system". FAO Corporate Document Repository. Retrieved 2010-05-23.
- "Indian assistance of Rs. 15.66 crore in Jhapa and Ilam districts". Press Release. Indian Embassy. Retrieved 2010-05-23.
- Dwarika N. Dhungel, Santa B. Pun. The Nepal-India Water Relationship. Google books. Retrieved 2010-05-23.
- "Maghe Sankranti - festivals - Nepal". Retrieved 2010-05-23.
- "Mechi Zone". Retrieved 2010-05-23.