 Where it passes through Bristol the river was prone to flooding , but the Northern Stormwater Interceptor , running from Eastville Sluices to the River Avon downstream of Clifton Suspension Bridge , has since been constructed to control this . At Wade Street , St Judes , the river enters an underground culvert , emerging at what Bristolians call The Centre ( formerly the ' Tramways Centre ' ) , but only when there is a risk of flooding . The river is otherwise channelled through Mylne 's Culvert into the River Avon at a point between Bathurst Basin and Gaol Ferry Bridge . Three further flood relief <unk> Castle Ditch , Fosseway and Castle Green Tunnel - run under Castle Park in central Bristol to carry excess flows into the Floating Harbour . 
