Bihar is India’s most flood-prone State, with 76% of the population in the north Bihar living under the recurring threat of flood devastation. According to some historical data, 16.5% of the total flood affected area in India is located in Bihar while 22.1% of the flood affected population in India lives in Bihar. About 68,800 square kilometres (26,600 sq mi) out of total geographical area of 94,160 square kilometres (36,360 sq mi) comprising 73.06% is flood affected. Floods in Bihar are a recurring disaster which on an annual basis destroys thousands of human lives apart from livestock and assets worth millions.
History of Flood in Bihar
The plains of Bihar, adjoining Nepal, are drained by a number of rivers that have their catchments in the steep and geologically nascent Himalayas. Kosi, Gandak,Burhi Gandak, Bagmati, Kamla Balan, Mahananda and Adhwara Group of rivers originates in Nepal, carry high discharge and very high sediment load and drops it down in the plains of Bihar. About 65% of catchments area of these rivers falls in Nepal/Tibet and only 35% of catchments area lies in Bihar. A review by Kale (1997) indicated that the plains of north Bihar have recorded the highest number of floods during the last 30years. In the years 1978, 1987, 1998, 2004 and 2007 Bihar witnessed high magnitudes of flood. The total area affected by floods has also increased during these years. Flood of 2004 demonstrates the severity of flood problem when a vast area of 23490 Sq Km was badly affected by the floods of Bagmati, Kamla & Adhwara groups of rivers causing loss of about 800 human lives, even when Ganga, the master drain was flowing low.
Flood highlights during (1998-2012)
In the year 1998 maximum discharge in the first week of July in most of the rivers in North Bihar caused excessive pressure on the embankment along the rivers resulting in damages at several places. Embankments of Burhi Gandak, Bagmati, Adhwara and Kosi were partially damaged. Three hundred and eighty one persons died and public property worth rupees 9,284 lacs was damaged. There was crop damage of about rupees 36,696.68 lacs.
In the year 1999 there was unexpected heavy rains in the month of October in the catchments in Nepal and flood level suddenly touched the 1987 HFL at JhanjharpurRailwayBridge in Kamla Balan river and the spurs in Kosi river experienced threat throughout the flood season. Crop of rupees 24,203.88 lacs, and public property of rupees 5409.99 lacs were damaged.
In the year 2000 Kamla Balan and Bhutahi Balan catchments received heavy rainfall during first and last week of July resulting in unexpected rise of water level. In first week of August 2000 Eastern Kosi Afflux Bund was punctured.Twelve thousands thr