The walls under Tham Luong Bridge in District 12 have been covered by soot as people have burned rubbish dumped at the foot of the bridge.
Cho Cau Bridge in District 12 has become a trading place, despite bans.
"More traders are gathering here, turning the area at the bridge's foot into a small market," a local man named Quoc Cuong said. "We're facing difficulties getting through this area due to frequent traffic jams and it's always dirty with lots of litter left by the traders."
Another street-side market has also been illegally formed by vendors at Long Van Tu Bridge in Binh Thanh District, blocking traffic and causing pollution.
Meanwhile, the area under Nguyen Thai Son Overpass has been illegally used by a nearby timber company to store materials.
Ong Lanh Bridge which connects District 1 and District 4 in the city centre has also become store places for local people.
To deal with the situation, the HCM City Transport Department has just asked authorities in local districts and Thu Duc City to intensify the management and protection of local infrastructure including bridges, flyovers and tunnels in the city.