The impacts of upstream dams on the evolution of salinity intrusion at Mekong rivermouths

Abstract

   The changing of salinity intrusion at Mekong rivermouths has been occurring more complicated and significantly affecting the livelihood and sustainable development in Mekong River Delta (MRD). Located at the end of downstream of Mekong River, MRD is strongly affected by the development of reservoirs and hydropower dams in the main stream as well as tributaries. The flows at Kratie, Tan Chau - Chau Doc and measured salinity at rivermouths corresponding with stages of dam construction along the main stream of Upper Mekong in China are analyzed.It is elucidated the change of total discharge in flood and dry seasons affecting salinity intrusion evolution. The correlation between the discharge to MRD during dry season and salinity concentration measured at 4 stations in 4 rivermouths, respectively, thereafter was established in order to better understand the trend of salinity intrusion at Mekong rivermouths.