The man's wife told police that her husband, Athiwat Saithirachote, 62, who had construction and steel trading business, quarreled with her while they were driving. She said he parked the car on the bridge and came out to continue the quarrel before suddenly jumping off the bridge at 1pm.
Police said the wife initially tried to jump into the canal but she was restrained by passers-by.
Scuba divers searched the canal until dusk but they failed to locate the man and the search was suspended.