This Head Race has a website.
There is a Google map for this event.
There is no room for cars in the trailer park. Spectators need to park south of the river and upstream of Caversham Bridge.
There is a good tow path.
The easiest way for spectators to reach the trailer park is to walk north over Caversham Bridge and turn right immediately after the bridge into Promenade Road.
Results are normally available quite soon after the race.