Bui Thanh Giang, Deputy Director of Saigon Water Corporation (Sawaco), said the salinity of Saigon and Dong Nai rivers had recently exceed permissible levels 250mg per litres at certain points of time. Meanwhile, the El Nino weather phenomenon, that brings higher temperatures and less rain, has caused serious drought in the south, including HCM City, affecting water level on the rivers. This has meant water supply plants in the city are facing bigger difficulties sourcing water.

The salinity of Saigon and Dong Nai rivers had recently exceed permissible levels 250mg per litres
 

Giang added that since early this year, Tan Hiep water supply plant had to halt pumping water from the Saigon River on many occasions, forcing Sawaco to regulate water from the city’s entire system to ensure supply.

The amount of water stored in Dau Tieng Reservoir on the upper Saigon River is now estimated at 928 million cubic metres, only 76% of the lake’s storage capacity. Meanwhile, the level at Tri An on the Dong Nai River is equal to 80% of that of previous years. This is a major problem and makes it more difficult to dilute salt water intruding upon the Saigon River.

“Saigon and Dong Nai rivers are forecast to face between 4 and 8 salt intrusions between now and the end of June this year, depending on tides and monsoon, Giang warned.

To improve the situation, Sawaco has proposed building reservoirs in Cu Chi District which would store water taken from Saigon River to at least ensure water for Tan Hiep water supply plant and their total capacity would be large enough to store water for three-months of use in the city, according to Giang.

“Sawaco will have to upgrade technology to deal with the increasing saltwater intrusion. The firm needs to also raise the storage capacity at its plants,” Giang said.