Oxfordshire County Council inspected Playhatch Road, which has been closed for two weeks due to flooding, this morning and opened the road to through traffic on one side.
Temporary traffic lights are in place while officials assess the condition of the road, which has subsided in parts.
Spring Lane, which connects the road with Henley Road by the Flowing Spring pub, remains under water and is closed.
Before the bridge re-opened rush-hour drivers were again faced with long queues in Wargrave Road, Remenham Hill and Reading Road in Henley as well as in Caversham and on the A4 near Charvil.
David Nimmo Smith, the cabinet member for the environment on the county council, said he visited the site on Sunday evening and there was still water on the road.
He said: We wanted to wait for the river level to drop a little bit further before we re-opened it.
There were people driving round the Road closed signs. We cant condone that because it was closed for health and safety reasons.
Theres a 300m stretch of the road that is partly coned off where the temproary traffic lights are. The officers are going to do a proper assessment today because we think theres a bit of subsidence.
Flood warnings remain in place in communities along the River Thames between Henley and Medmenham and in Shiplake and Wargrave.
The Environment Agency says river levels have stabilised a but still remain very high. It said further property flooding was unlikely.
The Met Office issued yellow warnings of fog this morning as temperatures plummed to -1C but it forecasts mainly dry weather today and tomorrow.