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1 March 2014 Last updated at 17:16 GMT
Both the old bridge and the Second Severn Crossing will become publicly owned in 2018 once their original construction costs have been covered.
Campaigners are calling for the tolls to be lowered in the future.
The Department for Transport said no decision had been taken on the future management or tolling costs of the crossings after the end of the current concession.
A musical protest has taken place over the cost of crossing the River Severn.