The road is riddled with potholes, ruts and faded markings, with damage worsening in the rainy season along the stretch from Vung Tau Junction in Dong Nai to Phu My Ward in HCM City.
In An Phuoc Commune, the road has degraded severely, with peeling asphalt leaving behind wide, water-filled pits.
The 30-km stretch from Long Hung Ward to Long Thanh Commune in Dong Nai is full of potholes and craters. Numerous low-chassis cars have suffered damaged tyres, undercarriage scrapes, or fallen into holes while travelling through the area.
Despite a 100-metre section in Long Hung Ward being repaired, hundreds of potholes and craters still scar National Highway 51 through Dong Nai Province.
The section opposite Son Tien Tourist Area is badly damaged, with the surface stripped of markings and asphalt, and many spots deeply sunken. The section is prone to repeated deterioration during the rainy season.
Several stretches reinforced with concrete and asphalt have also peeled away, exposing steel frames and creating hazardous bumps for drivers.
Many median strips along National Highway 51 through Long Thanh Commune are in the same situation.
Maintenance hole covers on National Highway 51 are missing, prompting residents to place branches as makeshift warning signs. In many other spots, the drainage system has shifted or broken, leaving the road uneven and hazardous.
National Highway 51, a 72-km route that traverses Dong Nai and HCM City, was expanded to eight lanes in 2013, with a daily capacity of 12,000 vehicles. Today, it carries about 32,000, rising to 48,000 at peak times, placing heavy pressure on the infrastructure.