The River Parrett is a major river in Somerset and Dorset, England. It starts in the County of Dorset near Chedington. From here it flows in a northwesterly direction through the Somerset Levels to Bridgewater. It flows into the Bristol Channel close to Burnham-on-Sea. At the mouth of the river is Bridgewater Bay National Nature Reserve. The river is tidal for up to the hamlet of Oath, some south east of Bridgewater. The river has a very slight fall between Langport and Bridgwater, only 1 foot per mile, or 20 cm per km, and is prone to frequent flooding, in winter and high tides.