A geo-environmental assessment of flood dynamics in lower ajoy river inducing sand splay problem in eastern India

Abstract

Flood as a widespread destructive natural disaster is recurring in the river basins of Eastern India. Though large number of flood controlling measures have been taken in the river valleys from the early ages but it is to be noted that spatial dimension of the flood affected area and the magnitude of flood are being increased significantly year by year. The present alleviation measures are seemed to give false security to the bank dwellers. Once to protect the agricultural fields and the settlements embankments were constructed along both sides of the rivers but now the hydrologists feel that those human interventions have changed the character of the river regime. Consequent effect of it is the breaching of the embankments and the occurrences of sand splay over a massive area. Studies have made here in one of the important flood prone river basins of Eastern India, i.e. Ajoy, where the rate of sand splay formation has significantly hastened many times and it has a negative effect on the fertility of the agricultural fields. Some structural and non-structural measures have been suggested on the basis of the field observation.