Olivia Rowland and Peter: There is a river beach by the bridge over the Thames in Wallingford. The water is shallow and easily accessible (although the current is strong, particularly near the bridge) and there is a lovely view of Wallingford from the water and a nice field for a picnic after your swim. Access via the field from the road or the steps from the bridge.
Peter Stack: Lovely spot for swim,small beach for easy access ,nice steady current under bridge,
Just the obvious boats