The River Parrett has its source in the springs in the hills around Chedington in Dorset in England and flows west through the Somerset Levels to its mouth in the Bristol Channel at Burnham on Sea a town on the edge of Bridgwater Bay, an important Nature Reserve. The Parrett is tidal up to Oath Lock. During winter, the Parrett is prone to frequent flooding.In common with the lower reaches of the River Severn, the Parrett exhibits a tidal phenomenon known as the bore. At certain combinations of the tides, the rising water is funnelled up the river into a wave that travels rapidly upstream against the river current. The bore is a natural example of a self-reinforcing solitary wave or soliton.
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