As the roads expanded, more vehicles started to travel on them, worsening the situation.
Nguyen Cong Tuyen from Dong Da district said he thought traveling along Phap Van-Cau Gie highway would become more convenient after the upgrade.
However, it made traveling harder due to the significant increase in vehicles using the highway, particularly over the weekend and during the Tet (Lunar New Year) festival, he said.
"Shockingly, it took our family over an hour to queue up and pay the toll at the highway station during the Tet festival earlier this month," he said.
Tran Van Son, Head of the Directorate for Roads of Vietnam's Road Management Department 1, said during peak seasons like Tet, many measures were introduced to help reduce traffic congestion at toll stations, particularly on routes that are heavily used, such as the Phap Van-Cau Gie, which is considered the main thoroughfare to reach the southern localities.
More gates were opened at toll stations to collect the fees and more workers were assigned at these stations but congestion still occurred, he said.
It still took people hours to get past the toll stations, he added.
He suggested it was necessary to install a non-stop toll system or electronic toll collection system (ETC) to help end delays and cut costs.
The system would also help drivers reduce their traveling time and fuel usage as they would no longer have to stop their vehicles to manually pay fees, he said.
Experts estimate that the system could help save VND233 billion (US$10.4 million) worth of fuel each year.
It utilises radio frequency identification (RFID) technology in the form of a wireless system with two components: e-tags and readers.
To pay tolls through ETCs, vehicle owners will be issued an e-tag that is attached to the inside of the vehicle's front windscreen. This e-tag is in turn linked to an account for fee collection. Drivers can transfer money into the account via Internet banking or at transaction points.
When the vehicle passes a toll collection point, the RFID system installed at the toll station will activate a camera that will photograph the vehicle's number plate while reading the RFID tags.
The transport ministry plans to install ETCs at all toll booths nationwide from 2020.
The system has became operational at three toll stations, in Quang Binh, Nghe An and Dak Lak, on a trial basis.