... and improvement of the living standards for people of the Vietnam Government. The aims of these water works are: • to extend existing irrigation systems, mainly in the in the middle and upper ... hectares): mainly in the Long Xuyen - Ha Tien quadrangle, the Plain of Reeds, the West Hau river Fig.1: The Mekong River Basin and Land forms of the MD in Vietnam WATER QUALITY MANAGEMENT FOR ... complicated. The main factors are river discharge, local rainfall and runoff, the amplitude of tides in the East Sea and the Gulf of Thailand, the slope of the river bed, the wind velocity...