Sediment Load Linkage between Tonle Sap Lake and Mekong River and Towards the Mekong Delta
The overall balance of flow and sediment load between Tonle Sap Lake and Mekong River over the observation hydrological year 1995-2017 shows a net contribution of water from Tonle Sap Basin, as would be expected from such a large drainage area (Figure 10.a). 2004 was an exception, when the Mekong River at Chroy Chnagvar reached its maximum discharge 60,000 Mm3. The annual water balance indicates that Tonle Sap Lake contributes an average of 33,000 Mm3 during the low flow season to the Mekong Delta. However, the pattern of net sediment transfers changed over the observation period. From hydrological year 1995 to 2000, Tonle Sap River contributed more sediment load to Mekong River than it received via reverse flows, but from hydrological year 2001-2017 the Lake received more sediment from the Mekong River than it contributed (Figure 10.b), averaging 1.35±0.7 Mt per year.