Anility intrustion in Sai Gon-Dong Nai river system under the effects of the tides and sea level rising in Vung Tau estuary – east sea, south of Vietnam

Abstract

A mathematical model was used by the authors (software developed by Dr. F28 Le Song Giang) to study the change of the salt boundary river systems Saigon - Dong Nai under the effect of sea level rise in the different cases for Ho Chi Minh City, taking into account the change of amplitude and phase shift of the South China Sea tide.

Results of the study indicated that:

1.      There is a pretty good resemblance between model running results and results of water levels measurement. Salinity, calculated results have a larger amplitude slightly from measured data but this difference and oscillation phase can be acceptable

2.      Salinity 1 g / l - 3 g / l is increasingly encroaching into the infield under the sea level rise scenarios. Salt accounts is greater than 5 g / l and the margin of 10-15 g / l is also approaching deeply, so the future of Ho Chi Minh City will face to some water supply problems.

3.      Saline in basin downstream Saigon - Dong Nai river is quite sensitive to the hydrological regime of the river, therefore, domestic regulation of irrigation reservoirs upstream can be used to push salt and improve salinity regime in the downstream part of the river.