The Town of Cary said a 12-inch sinkhole occurred after 1 p.m.
The road gave way shortly after and a dump truck belonging to the town fell in.
A part of Brookgreen Drive is closed between Larkhall Court and Gatehouse Drive.
Crews are still on scene repairing the water main break and the hole.
The road closure will not affect residents - only through traffic.
No injuries were reported.