There are
819 mi
from Waterloo, IA to Duncanville, TX
That's the driving distance. It would take 15 hours 32 mins to go from Waterloo, Iowa to Duncanville, Texas.
The flight distance (direct flight from Waterloo, IA to Duncanville, TX) is 724.15 mi.
819 mi = 1,317.37 kms