Residents in Ho Chi Minh City who continue to consume groundwater face severe health problems, a new study has found.
The study by the city’s Preventive Health Department, based on surveys conducted last July, found that 62 percent of groundwater samples in the city were contaminated.
Levels of ammonium, iron and manganese exceeded safety standards in samples taken across the city. Some contained more than six times the safe amount of ammonium, it said, as cited by Tuoi Tre (Youth) newspaper.
Many samples also contained the E. coli bacteria, which can cause serious food poisoning.
Every day, people in the southern metropolis use more than 716,000 cubic meters of groundwater, enough to fill 280 Olympic swimming pools.
The city’s environment department plans to reduce that amount to 100,000 cubic meters by 2025, but there’s no legal way of stopping people from tapping the free resource. Current regulations allow people to use groundwater without having to ask for permission if they use less than 10 cubic meters a day.
The Saigon Water Corporation, the city’s main water supplier, said more than 109,000 families in the city still use groundwater despite having access to tap water.
Some people said they have had trouble installing pipes, so they still rely on groundwater.
Doctors from the preventive health center said most people who consume groundwater in the city are unable to effectively purify the supply.
They said that ammonium can transform into nitrate or nitrite compounds that can trigger cancer.
Health risks aside, the use of groundwater has been blamed for making the city more vulnerable to flooding.
Water and climate change researchers at the Vietnam National University-HCMC said surveillance images show that the city is sinking on a large scale.
Dr. Pham Van Long from the Vietnam Society for Soil Mechanics and Geotechnical Engineering said that with the current rate of groundwater depletion, some areas of the city will sink by one meter (3.3 feet) by 2050.