The river becomes tidal at Maisemore, on the West Channel just north of Gloucester, and at Llanthony Weir on the East Channel. The tidal river downstream from Gloucester is sometimes referred to as the Severn Estuary, but the river is usually considered to become the Severn Estuary after the Second Severn Crossing near Severn Beach, South Gloucestershire (the point to which the jurisdiction of the Gloucester Harbour Trustees extends), or at Aust, the site of the Severn Bridge.
where does the river severn stop being tidal
at Maisemore, on the West Channel just north of Gloucester, and at Llanthony Weir on the East Channel