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.