2 nd International Conference on Emerging Trends in Engineering & Technology, April 12-13, 2013 College of Engineering, Teerthanker Mahaveer University. River Kosi, Sorrow of India: An overview Mohd Danish 1 , Priyank Gupta 1 , Dr. Javed Alam 2 , Prof. Mohd. Muzammil 3 The Kosi River which is one of the largest tributaries of the river Ganges is infamous for floods, thus causes huge losses in terms of both life and property. India, after Bangladesh, is the second in the world in loss due to floods, thus accounting for one-fifth of the deaths due to floods, globally. The Kosi River is considered as the sorrow of Bihar. It is one of the two major tributaries of the river Ganges(the other river being Gandak) draining the plains of north Bihar. Despite a long history of flood control management in the basin for more than 5 decades, this River continues to bring a lot of misery through extensive flooding. Meandering is another bizarre behaviour of this river which have shifted laterally about 112 km westward in the last 250 years. Due to this, the river which previously flowed near Purnea in the 18th century is now flowing to the west of Saharsa. The meandering behaviour of the Kosi River has wasted an area of about 1,295 Sq. Km of land in Nepal and about 7,770 Sq. Km of land in Bihar, resulting in sand deposition. This wasted land was considered as the garden of Bihar and it was renowned for its rice-field and orchards. In the course of shifting it has wiped out many towns and villages inflicting heavy losses of human, cattle life and property. The present paper presents an overview of the behaviour of River Kosi and its shifting pattern in its total reach with a focus on the structural and non-structural works carried out in this connection so far. Keywords: Kosi River, The Ganges, Watershed, Meandering 1. Introduction India is seventh largest country with geographical area 32,87,263 km 2 (2.45% of the World’s land resources) and the second most populous country with over 1.2 billion people (17.5 % of the World’s population) and it holds 4% of the world’s fresh water resources [1]. Rivers in India are not only considered as a source of water but also it has been worshipped from centuries. The major river systems in India are Indus, Brahmaputra, Ganga, Yamuna, Narmada, Tapti, Godavari, Krishna, Cauvery and Mahanadi. The Ganges is the second largest river in the world in terms of water discharge and the Ganga-Brahmaputra river system forms the largest delta in the world, known as Sunderban. These are two of the various reasons for which Indian rivers are famous in the World. The Ganges has many tributaries and Kosi River is one of them. Kosi river has been the centre of attraction for India for several years due to various reasons, primarily, due to floods. Several researches have been done to control this river and several techniques have also been proposed and implemented but the Kosi has continued to haunt common people every year. 1. M. Tech. Student, Department of Civil Engineering, Aligarh Muslim University, Aligarh, India. Email: erdanish.amu@gmail.com , Email: priyank9092@gmail.com 2. Associate Professor, Department of Civil Engineering, Aligarh Muslim University, Aligarh, India. Email: javed_alig2000@yahoo.co.in , mob: +91-9837169427 3. Professor, Department of Civil Engineering, Aligarh Muslim University, Aligarh, India. Nayak [2] has studied the sediment management in Kosi to control the river. Sinha et. al. [3] studied the flooding problem in the Kosi river basin and presents an in-depth analysis of flood hydrology. They also integrated the hydrological analysis with a GIS-based flood risk mapping in parts of the basin. 2. Origin of Kosi River The Kosi River flows between the boundary of Nepal and India and it is one of the largest tributaries of the Ganges. The river along with its tributaries drains a total area of 69,300 km 2 up to its confluence with the Ganges in India. This also includes parts of Tibet, Mount Everest region and the eastern third of Nepal. The river basin is surrounded by the ridges separating it from the Brahmaputra in the north, the Gandak in the west, the Mahanadi in the east and the Ganges in the south. Fig. 1 shows the satellite view of the Kosi River showing its origin from Nepal flowing into India along its path. 3. Problems caused by the Kosi River Kosi River has caused many problems to the common people and to the country morale. These are discussed in the following sections. 3.1. Meandering of River A river that winds a course not in a straight line but in a sinusoidal pattern is called a meandering river. Its continued action of secondary flow developed on the river bends that cause further erosion on the outer bank and deposition on the inner bank. The meandering action increases the length of the river and tends to