Long-term planning is needed to cope with worsening pollution in the Sai Gon and Dong Nai rivers, experts have warned.
The Sai Gon and Dong Nai rivers in HCM City have become more and more polluted due to increasing levels of household and industrial waste water.
Hundreds of tonnes of household waste and industrial waste from factories and industrial parks in HCM City and Binh Duong Province are discharged into the rivers every day, according to the Institute of Natural Resources and Environment.
In the 2011-12 period, the dissolved oxygen (DO) content in the Sai Gon River was extremely low while the content of ammonia, manganese, micro-organisms and suspended solids was higher, indicating a high level of pollution, said the institute.
Only 20 per cent of household wastewater had been treated before being discharged into the rivers, it added.
In 2010, in HCM City alone, the volume of household waste water reached nearly 1.20 million cubic metres per day.
In addition, around 50 industrial parks in the city discharge about 104,129 cubic metres of industrial waste water every day.
Wastewater from hospitals reaches 10,142 cubic metres per day, and waste water from the breeding sector, 950,059 cubic metres per day.
The pollution of these rivers has posed a threat to millions of residents in HCM City as this is a source of tap water for the residents.
The HCM City-based Tan Hiep water supply company has a capacity of 300,000 cubic metres per day, and the Binh Duong-based Thu Dau Mot water company supplies 30,000 cubic metres per day, both of which process water from the river.
However, tests from the Institute of Natural Resources and Environment have shown that the quality of water of areas near these two water-supply companies does not meet the national standards.
Wastewater from hospitals is discharged directly into the river through city drains.
Solutions
Nguyen Van Phuoc, chief of the Institute of Natural Resources and Environment, said drastic measures should be carried out at once to protect the water quality of the Sai Gon and Dong Nai rivers.
To reduce the pollution of the rivers, experts have recommended that affected provinces divide the river into zones to receive waste water.
Any companies or sectors that have a high risk of causing river pollution should not be granted operation licenses in areas that supply tap water for residents.
Experts have also recommended that the city build a new urban sewage system and an underground-water observation system.
City authorities must ensure that all wastewater from companies at industrial parks as well as from hospitals must be treated before being discharged into the rivers, they said.
Nguyen Ngoc Anh of the HCM City Irrigation Association said that protecting the Sai Gon River was not enough, and that the city should also protect the entire system of the Dong Nai River basin.
Anh suggested that priority be given to areas that supply tap water for residents in HCM City and Binh Duong Province.
The city also needs to protect land along rivers where residents build makeshift homes and other structures. The riverbanks are often packed with rubbish, according to Anh.
