A man died after falling into an open sewer in Ho Chi Minmh's Binh Tan District on Friday.
The water around the sewer was about 2m deep following flooding, and it was not protected by a grate when the accident happened.
Workers had opened the sewer as part of ongoing upgrade work, but did not replace the grate, said Nguyen Ngoc Cong, director of the Ho Chi Minh City Anti-Flooding Center, the project's investor.
The center will punish those responsible for the accident, Cong said.
Last weekend, an eight-year-old boy was washed down a sewer in a street in the southern province of Binh Duong after heavy rains combined with high tides to cause flash floods in the area.
A similar incident occurred in Binh Duong in September 2014 when a nine-year-old boy was pulled into a manhole on the sidewalk after the cover was washed away by heavy rain. The body of the boy was found two days later, around 700 meters away.
In October 2014, a five-year-old boy who fell into a flooded underground sewer in Quang Ngai Province in central Vietnam was luckier after locals acted quickly to open a manhole 40 meters away and pull him out. The boy was already unconscious and only coughed up water after five minutes of CPR.