Hydromorphology of the Kargalinsky channel – the main distributary system of the Terek river delta

The main natural factors determining the specifics of the Terek delta channel regime are related to increased sediment runoff and low channel stability. Sediment yield of the Terek is comparable to the largest rivers of Russia – the Ob, Yenisei, Lena, despite the fact that the water runoff is ten times smaller. For many centuries, people were adapting to the unpredictable nature of the riverbed and water regime of the Terek, which repeatedly changed the direction of its main flow after reaching the Caspian lowland. The present study presents the results of recent studies of the hydromorphology of the Kargalinsky channel, which is former avulsion channel and today is the main distributary of the Terek River delta, where more than 90 % of the total water and sediment runoff is discharged. An assessment is given of the variability of the rate and direction of channel changes along its length, the nature of the influence of fluctuations in the level of the Caspian Sea on the dynamics of the channel. The purposes of channel management are also discussed.