Flood hazard mitigation in Barpeta district, Assam, north-east India

Abstract

Flood is almost an annual feature in the district of Barpeta, Assam. The geographical area of the district is that it comprises 4.2 percent of the total area of the state. The district is prone to severe flood hazard mainly by the rivers Manas, Beki, Pahumara, Kaldia and their tributaries. The average annual peak discharge four rivers Manas, Beki, Pahumara and Kaldia are found to be 275.04, 3219.85, 139.48 and 163 m³/sec, respectively. The recurring floods of characteristically high magnitude have assumed devastating heavily affecting the agricultural lands, crops cattle and people of the district. The structural and non-structural mitigation measures taken by the state government to provide reasonable flood protection have been studied carefully. Embankment is the main structural feature used to mitigate floods in the district. It has been observed that percentage of total affected area is increasing with subsequent increase in length of the embankments. In recent years, breaches in embankment have shown an increasing trend. Other temporary and light protection measures are boulder bars, spurs and boulder filled dams. These measures are now insufficient to mitigate severe flood. The strategies for flood management in Barpeta district have taken for discussion in the light of recent thrust on flood management. Non-structural measures including watershed management and flood plain also studied in this context. Journal of Nepal Geological Society, 2007, Vol. 36 (Sp. Issue) p.26