Blackish water has appeared over the past few days on a five-kilometer stretch of a beach in Da Nang, raising pollution concerns.
Thick yellow foam and a foul smell were also reported by locals, who have been afraid to go into the water for fear of catching diseases.
The affected body of water is located along Nguyen Tat Thanh Street, spanning Da Nang’s Thanh Khe and Lien Chieu Districts.
There are 28 sewer openings located along this stretch of beach, which receives the largest daily volume of treated wastewater in Vietnam, according to Mai Ma, director of a local sewage treatment company.
Ma’s company runs a sewage treatment plant that collects both rainwater and household wastewater from local rivers for treatment before discharging treated water into the ocean.
At times, heavy rains can cause the plant’s systems to become overloaded, leading to untreated sewage leaking into the ocean, the director explained.
However, as it has not rained in Da Nang in the past few days, this has been ruled out as a possible cause for the recently spotted blackish sea water.
A spokesperson from the environment watchdog of Da Nang told Tuoi Tre (Youth) newspaper on Sunday evening that officials had collected water samples from the affected area for lab tests to determine what had caused the water to turn blackish.
The administration of Da Nang has earmarked multiple investments for upgrading the capacity of local sewage treatment plants, as well as asking upstream factories to treat their own wastewater before discharging it into rivers.