Evaluation of Factors Contributing to Floods in the Outlet Part of the Kura River, Azerbaijan

Abstract

Flow regulation has long been thought as the most effective method for the flood prevention. However, this experience has shown its limitations over the last few decades when the strong floods have been observed in regulated rivers. Since most of rivers have been highly affected by human activities, there are obvious changes in the genesis and nature of floods. Floods at the mouth part of the Kura River are observed as a combined result of climatic and non-climatic factors. Climatic factors directly impact flood characteristics-peak, duration and volume. Main climatic factors of floods in the Kura River include intense snowmelt episodes and intense rain as well as Caspian Sea level changes. Non-climatic factors include changes in land use, deforestation, erosion, flow regulation, water withdrawals and channel siltation. Over the past century, there is an increased contribution of non climatic factors to the flood formation processes in the Kura River. At the same time channel siltation has increased the role of non-climatic factors. In addition, the Caspian Sea level rise became additional contribution to the level rise in the mouth area that causes backwater propagation on the free surface. Due to the channel siltation and the backwater propagation at the mouth reach, floods may occur even during lower discharges characterized with longer durations.