The Gloucester Harbour Trustees are the Competent Harbour Authority (CHA) for the tidal part of the River Severn from the Gloucester weirs (Llanthony & Maisemore) down to just below the Second Severn Crossing, on the Welsh side of the Severn Estuary (north of Denny Island) from the Second Severn Crossing as far as Goldcliff, and on the River Wye up to its tidal limit (Bigsweir).
It was built in 1876 during the construction of the line on the Monmouthshire side of the River Wye at Bigsweir, and was intended to serve the nearby villages of St Briavels across the river in the Forest of Dean and Llandogo which is further down the Wye Valley.