Vietnam's tallest building Landmark 81 is covered in haze in HCMC, August 2019. Photo by VnExpress/Thanh Nguyen.

To cost VND495 billion ($21.3 million), it would monitor every component of the environment, said Cao Tung Son, director of the city Department of Natural Resources and Environment's (DNRE) Center for Environmental Monitoring.

The automatic system will monitor the quality of the air, surface water and groundwater and land subsidence. The data collected will be sent to the central system for analysis by the DNRE and issuance of public warnings.

For monitoring the air, the department is setting up two stations at the Saigon Hi-tech Park in District 9 and Binh Tan District Education Office to collect data every five minutes.

This will help calculate the air quality index (AQI), something the manual monitoring methods in the city cannot do.

The stations are being evaluated and having their equipment tested now, and will soon begin operation.

HCMC, Vietnam's largest, has been choked by haze regularly this year. The air quality index in the city reached unhealthy levels on many days since September. The authorities said exhaust from around 10 million vehicles is one of the three major causes of air pollution in the city, besides smoke from 1,000 large factories and dust from numerous construction sites.

By 2030 the city plans to install 16 more air monitoring stations at major intersections, residential areas and industrial parks.

"By then HCMC’s monitoring frequency will be five times the rate required under regulations set by the Ministry of Natural Resources and Environment," Son said.

The frequency will also depend on each individual locality's needs and financial capacity.

To monitor the water quality, the project will install stations at different points in the rivers and five canals in the inner city. There will also be two stations to monitor wastewater quality along the Saigon River.

This will enable a thorough evaluation of the impacts of residential wastewater and industrial effluents on HCMC's water bodies.

The city currently only treats a fifth of its total daily wastewater discharge, or 370,624 cubic meters.

Under the new environment monitoring project, the city will also use high-tech tools to dig deep into the ground to determine subsidence levels and what causes them.

Parts of Saigon have sunk by up to 81.4 cm over the past decade, according to a survey by the Ministry of Natural Resources and Environment. The subsidence was caused by a combination of both natural and human activities, including excessive groundwater extraction and impacts of urban construction, infrastructure and traffic.

Since the city also suffers from fault-induced subsidence, the phenomenon has to be monitored over the long term.

Son said environmental quality trends have to be quantified, and investment in modern technology would help generate faster and more accurate results.

"This will enable the public to get regular information about the environment and predictions through apps akin to AirVisual and PamAir."

The project is in the feasibility study phase and will be submitted to an evaluation council and then to people’s council for approval.

HCMC has been monitoring its environmental quality since 1993 when the Law on Environmental Protection came into effect.

It has 30 manual air monitoring stations.