Hydrometeorological aspects of floods in India

The Indian sub-continent being located in the heart of the summer monsoon belt, receives in most parts more than 75% of its annual rainfall during the four monsoon months of June to September. As the bulk of summer monsoon rainfall occurs within a period of four months, naturally majority of floods occur in Indian rivers during this season only. The ground conditions also help in generating high percentage of run-off because of the antecedent wet conditions caused by rainy spells occurring within the monsoon period itself. Besides mentioning different weather systems, which cause heavy rainfall and consequent floods, a detailed discussion of 15 years' floods in different river systems has also been given in the article. This study has shown that the flood problem in India is mostly confined to the states located in the Indo-Gangetic plains, northeast India and occasionally in the rivers of Central India.