The report by the Ministry of Natural Resources and Environment said that on average, during more than 70 days of the year dust concentrations of PM10 and PM2.5 are much higher than the permitted concentration.
In the northern region, winter days between November and March often record higher dust concentrations than other days.
Only 42 of about 790 urban areas across the country have wastewater treatment systems meeting standards, the report said. In Hanoi, only 20.6% of household wastewater is treated before being discharged into the environment.
Rivers, lakes and canals in Hanoi and Ho Chi Minh City are the most polluted, among To Lich, Lu and Set rivers in Hanoi, and Tan Hoa–Lo Gom, Ba Bo, Tham Luong canals in HCM City.
The report also pointed out that 46% of underground water in Hanoi was found to contain higher than permitted arsenic concentrations, especially in the two districts of Hoang Mai and Long Bien.
Although 85% of solid waste was collected in urban areas of the country, the percentage of solid waste treated according to standards was very small.
The report said solid waste was mainly treated by burying and burning, but most dumping sites and incinerators failed to meet standards.
Urban areas have suffered from flooding during torrential rains in recent years, especially in Hanoi and HCM City.
Hoang Duong Tung, deputy director of the ministry’s Vietnam Environment Administration, said vehicle fumes and construction sites are mainly to blame for air pollution in urban areas.
Coaches and trucks were found to mainly discharge nitrogen dioxide (NO2) and sulfur dioxide (SO2), while motorbikes mainly emit carbon monoxide (CO) and volatile organic compounds (VOC), he said.
Vietnam now has about 47 million motorbikes and about three million cars, he said.
Increasing population in urban areas and inadequate infrastructure were responsible for the virtually total absence of wastewater treatment systems meeting standards, he said.
The small rate of solid waste treated in urban areas is attributed to lack of investment and backward technologies for collecting and treating waste, he said.
Poor drainage systems due to poor planning in urban areas was the main cause of flooding, he said, adding that high tides triggered by climate change also resulted in the inundations in big cities, such as HCM City.
The report also provided recommendations to remedy the problems. Authorised agencies were advised to tighten control to minimise emission sources, including conducting more checks on vehicle emissions as well as ensuring sanitation at construction sites.
Additional wastewater treatment systems need to be built in urban areas and drainage systems upgraded to prevent flooding during torrential rains and high tides.
The administration of urban areas was asked to invest more in new technologies to improve their capacity to treat waste.
The national environmental report included a section on major environmental incidents in 2016.
The first was the massive fish deaths in four coastal provinces caused by the Taiwanese Hung Nghiep Formosa Ha Tinh Steel Corporation in April 2016 by releasing toxic wastewater into the sea. The company has compensated the people affected.
The report also mentioned the water pollution in Buoi river in the northern province of Hoa Binh between March and April 2016, after a factory discharged untreated wastewater into the river.
Also listed was the case of 190 tonnes of fish killed by water pollution in Hanoi’s West Lake in September.
The next incident was the collapse of the reservoir of the titanium exploitation project implemented by Tan Quang Cuong Company in Binh Thuan province, leaving thousands of cubic metres of red mud overflowing into Nam Thuan Quy tourism site and flooding the roads.
The ministry said poor management by the local administration and poor implementation of environmental protection by the mine’s owners were to blame.
Agencies must draw lessons from these painful incidents to ensure such disasters do not recur, the ministry said.