A Plan for the Enhancement of Backwater for Irrigation for Sustainable Livelihood of Rural Communities at Magrahat Basin, South 24 Parganas, West Bengal

Management measure for Irrigation water by tidal back-water influx is an important issue for the sustainable living of rural communities in the areas where the rainfall is insufficient for rabi crop cultivation. Tidal back-water influx is one of the sources of irrigation water in the lower gangetic planes of West Bengal, India. Based on that concept, a plan is provided for the Magrahat basin of South 24 Parganas district in West Bengal for the augmentation of irrigation facilities through excess amount of tidal back-water entry during the post-monsoon period when the salinity of water is considerably low. In the present study, twenty major canals or khals of Magarahat basin are considered. Volume of available tidal water for irrigation of rabi crops was determined from the gauge data of tidal rivers. Here an attempt has been made to delineate not only the enhancement of the economic return of the people of the Magrahat basin but also to create provision for multi-cropping (rabi crops) pattern of agriculture/horticulture facilities during the dry season for sustaining of their livelihood. Also the tidal backwater surface profiles have been suggested for all the major canals of Magrahat basin using standard step method of gradually varied flow.