The Madison Street overpass shut down at 4 p.m. Thursday. City engineers say the overpass is more than 30 years old.
The city says the state DOT is footing the bill for the project that will replace the existing bridge with a larger and safer structure.
Local resident Phillip Pettis says, "I think it's ok. It's making the whole neighborhood look much nicer and everything. It's been a long time, and it's a big change, and that's good for the city."
Thomasville police are asking drivers to drive slowly, obey new traffic signs and be extra cautious as they make their way through detours around the bridge.
Police say westbound drivers should take Jerger Street to Broad Street, and eastbound drivers should take North Street to Broad Street.