ECN site code: R05
ECN monitoring by: Cyfoeth Naturiol Cymru - Natural Resources Wales

The River Wye is one of the largest rivers in Britain. It rises on the Plynlimon mountains at 741m AOD and flows through several towns including Rhayader, Builth Wells, Hay-on-Wye and Hereford before meeting the Severn Estuary at Chepstow. The total catchment area is 4136 km2 and the population size of 226,000 is centred on the main towns. The River Wye catchment is one of idyllic beauty and unspoilt scenery. The River Wye itself is a Site of Special Scientific Interest and one of the most important rivers in Britain in nature conservation terms. Much of the lower valley is an Area of Outstanding Natural Beauty.

The surface water in the Wye and its tributaries is mostly unpolluted, so much of it is suitable as a source of drinking water and for supporting a salmon and trout fishery. Nevertheless, certain rivers and streams in the upper catchment suffer from acidification and localised pollution problems from inadequate sewerage and agricultural sources also exist. The Wye is one of the best known salmon rivers in England and Wales. Shad and Sea Lamprey also migrate into the Wye. The river corridor supports a variety of plant communities, otters, water voles, several bat species, dippers, sandmartins, kingfishers and little ringed plovers. The biological quality of the river is generally good and supports several rare or scarce species including the mayfly Potamanthus luteus , the freshwater pearl mussel Margaritifera margaritifera and the native crayfish. The river also supports several rare species of non-aquatic invertebrates associated with gravel shoals.

River levels on the Wye (Multiple gauging stations; Natural Resources Wales)