Carries Minor road (B478) Material Concrete Cross River Thames | Crosses River Thames Opened 1986 Locale Sonning Eye | |
 | ||
Sonning Backwater Bridges are two road bridges across two branches of the River Thames at Sonning Eye, Oxfordshire, England. Built in 1986 to replace an older wooden structure, the bridges span Sonning Backwater and the millrace to link historic brick arch Sonning Bridge of 1775, which spans the boundary with Berkshire to connect the village of Sonning, with the smaller hamlet of Sonning Eye. Just upstream along the backwater is a weir next to Sonning Lock on the main navigable branch of the river.
Close to the bridge are the Mill at Sonning, now a theatre, on an island between two branches of the river, and the French Horn, a hotel and restaurant on the northern Oxfordshire bank.
The modern backwater bridges replaced a wooden and somewhat rickety structure. At the beginning of the 20th century, there were complaints about the traction engines causing structural problems with the old wooden bridge and disturbing the peace, much as there is with traffic today. The road (the B478) is the busiest B road in Oxfordshire, being the only way for road vehicles to cross the Thames between Henley-on-Thames and Reading.
The bridges are occasionally inundated or closed to traffic when the Thames is in extreme flood; the waters regularly rise to the steps of the famous French Horn restaurant and submerge the car park of the nearby Flowing Spring pub.