According to the Ministry of Construction, only six urban areas in Vietnam have centralised waste-water treatment systems and there are only 14 stations.

A Wastewater Treatment System at Nhon Trach II Industrial Zone in southern Dong Nai Province.

The areas comprise Hanoi, Ho Chi Minh City, Ha Long City, Danang City, Da Lat City and Buon Me Thuot City.

A Conference on Decentralised Wastewater Treatment and Management in Urban Areas held jointly by the Ministry of Construction and The German Organisation for Technical Cooperation (GTZ) was held in Hanoi on December 8 addressing the issues of waste-water treatment.

Speaking at the event, Nguyen Hong Tien, Head of the Technical Infrastructure Department under the Ministry of Construction, said many big cities such as Quy Nhon in Binh Dinh Province and Nha Trang in Khanh Hoa Province, do not have centralised waste-water treatment stations. Household waste-water is preliminarily processed through septic tanks, then directly discharged into the environment.

The rate of households connected to urban drainage systems remains low. Many drain systems are substandard and downgraded, while concrete also affects drainage.

By late 2009, just 74 out of 171 industrial parks in Vietnam had waste-water treatment facilities, 22 were building these facilities and 75 others did not have them.

The situation is attributed to the impact of the urbanisation process which has reduced areas of ponds and lakes while increasing developed land area. Degradation of drainage systems, lack of investment capital and limited awareness of the community also affect drainage in Vietnamese urban areas.

Total waste-water in Hanoi is estimated to be about around 670,000 m3/day, including 400,000 m3 of urban wastewater. However, only 47,000 m3, or 7%, of the total is processed per day.

At the conference, experts discussed the use of decentralised waste-water treatment method to provide environmental hygiene solutions to areas which are not connected to centralised waste-water treatment stations. Most of the decentralised waste-water treatment projects are small-scaled, often carried out within less than one year and have low costs. Therefore, they can be an effective measure to improve the drainage in Vietnam’s urban areas.

Despite being a new method in Vietnam, the decentralised wastewater treatment method is applied in a number of projects in Vietnam, including in Thanh Hoa Paediatrics Hospital and Cai Khe Market in Can Tho City.

Meanwhile, centralised wastewater treatment methods, which link all households’ drainage with one or many large-scaled treatment stations, require high technology and heavy investments. Particularly, implementation of these projects needs high accuracy which, nevertheless, is a difficulty for Vietnamese contractors.

At the conference, experts suggested Vietnam consider combining these two methods to optimise the efficiency of wastewater treatment projects.