River Wye. The River Wye is the fifth-longest river in the UK, stretching some 215 kilometres from its source on Plynlimon in mid Wales to the Severn estuary. For much of its length the river forms part of the border between England and Wales. The Wye Valley is an Area of Outstanding Natural Beauty. The Wye is important for nature conservation and recreation. The meaning of the name is not clear. Possibly the earliest reference to the name is Guoy in Nennius' early 9th Century Historia Brittonum and the modern Welsh name is Gwy. The Wye was much later given a Latin name Vaga, an adjective meaning 'wandering'. The Tithe map references a Vagas Field in both Whitchurch and Chepstow. Philologists such as Edward Lye and Joseph Bosworth in the 18th and early 19th centuries suggested an Old English derivation from wæg, wave. The source of the Wye is in the Welsh mountains at Plynlimon. It flows through or past several towns and villages including Rhayader, Builth Wells, Hay-on-Wye, Hereford, Ross-on-Wye, Symonds Yat, Monmouth and Tintern, meeting the Severn estuary just below Chepstow. Its total length is 134 miles. The lower 16 miles of the river from Redbrook to Chepstow forms the border between England and Wales. The River Wye is protected by two Sites of Special Scientific Interest, one covering the Upper Wye above Hay-on-Wye, and one covering the Lower Wye downstream to Chepstow. The criteria for inclusion of the river as an SSSI include geology, topography, flora, mammals, invertebrates, fish and birdlife, as the river and its tributaries constitute a large linear ecosystem. The Lower Wye SSSI is itself divided into seven units of assessment set by Natural England, and administrative responsibilities are shared between the councils of Powys, Herefordshire, Gloucestershire, and Monmouthshire. The Wye abuts a range of other SSSIs in England and Wales, including the Upper Wye Gorge and Lower Wye Gorge. It is also a Special Area of Conservation and one of the most important rivers in the UK for nature conservation. It is an important migration route and wildlife corridor, as well as a key breeding area for many nationally and internationally important species. The river supports a range of species and habitats covered by European Directives and those listed under Schedule 5 of the Wildlife and Countryside Act 1981. In Powys the river lies within the Radnorshire Environmentally Sensitive Area. Much of the lower valley is an Area of Outstanding Natural Beauty. The Lower Wye has been designated as a salmonid fishery under the EC Freshwater Fish Directive. The Wye is largely unpolluted and used to be considered one of the best rivers for salmon fishing in the United Kingdom, outside Scotland. In the 1980s and 1990s salmon in the Wye declined dramatically. In 1967 the Wye rod catch was 7,864, and as recently as 1988 it was 6,401; but by 2002 it was only 357. It is now recovering from this low in response to the extensive habitat improvement work carried out by the Wye and Usk Foundation, set up to restore the spring salmon runs. In 2015 the five-year average once again climbed above 1,000 and it is now the third best salmon river in England and Wales, surpassed only by the Tyne and Wear. The Wye was particularly famous for its large spring salmon that had spent three or more years at sea before returning to spawn. They used to enter the river between January and June and sometimes reached weights of over 50 pounds, the largest recorded being 59 lb 8 oz landed after a long fight by Miss Doreen Davey from the Cowpond Pool at Winforton on 13 March 1923. The last recorded 50 lb rod-caught salmon from the Wye was taken in 1963 by Donald Parrish and weighed 51 lb 8 oz. Since the early 2000s the spring catch has been steadily recovering and salmon of over 35 lb have been reported every year since 2011. The Romans constructed a bridge of wood and stone just upstream of present-day Chepstow. The River Wye has been navigable up to Monmouth since at least the early 14th century. It was improved from there to a short distance below Hereford by William Sandys in the early 1660s with locks to enable vessels to pass weirs. According to Herefordshire Council Archaeology, these were flash locks. The work proved to be insufficiently substantial and in 1696 a further Act of Parliament authorised the County of Hereford to buy up and demolish the mills on the Wye and Lugg. All locks and weirs were removed, except that at New Weir forge below Goodrich, which survived until about 1815. This was paid for by a tax on the county.