Seasonal to semi-diurnal variability of water levels in the Vietnamese Mekong River was analyzed by using observational data sampled every 15 minutes from August 2010 to March 2012. The temporal pattern of the water level altered greatly among the upper, middle, and lower reaches of the Mekong River in the Mekong River Delta, which was due to differences in the relative contribution of river flows from upstream and tides from the sea. Results from a one-dimensional numerical experiment suggested that enhanced landward propagation of tides observed in the water level during dry seasons is caused mainly by the smaller amount of water discharge. The model result also indicated that the rise of coastal sea-level may increase the tidal range in the river.
[ FULL TEXT (pdf) ]