Environment and Ecology
The salmon's leap up the water...
The River Tyne at Hexham, Northumberland is now the most important river in England for Salmon, and its weir the most significant obstacle for migrating fish upstream and down. Salmon, sea trout, trout ells, lamprey and coarse fish are all obstructed, despite the picturesque sight of salmon leaping every season.
In 2010 we won the competitive tender for a major Feasibility Study on behalf of Tyne Rivers Trust for improved river passage at Hexham, engaging Prof. Malcolm Newson, BT Bell Civil Engineers, AMR Geomatics, and Stirling University Centre for River Ecosystem Science (CRESS) for specialist riverbed hydro-morphological, engineering, flow hydrology, topographical surveying, and fish passage expertise. As well as project managing the 9 month study we provided the principal environmental consultancy inputs, stakeholder and community engagement, constraints mapping, and options appraisal and presentation of solutions at this most challenging of sites.
The Study confirmed that many years of river dredging for gravel upstream and downstream of Hexham Bridge had caused severe scour at the weir, increasing the height of the drop, to the point where fish passage was significantly impeded under low and medium flows. The constraints of the site included the Grade 2* listed bridge and its 1771 timber foundations, an enormous range of river flows - from 40 cumecs up to an estimated 1700 cumecs in the great flood of late 2015-, a weir 100m wide with complex flow patterns, a potential hydro interest, as well as a number of local users including anglers, rowing and canoe clubs and public access at Tyne Green. Fisheries and fish pass specialists from the EA were involvd throughout.
The preferred option - the construction of a supplementary fish pass in a carefully selected location- was approved by the Trust. Elliotts then prepared further environmental assessment, EIA screening and scoping and pre-application consultations, (with engineering design provided by BT Bell), followed by a first-time successful planning application to Northumberland County Council and fish pass consent from the Environment Agency Fish Pass Panel.
And the benefits
Our pragmatic and expert team has produced an elegant solution, and the fish pass was constructed by the County Council direct labour force in Autumn 2015, used by migrating salmon almost immediately, and was offficially opened by celebrity Robson Green in March 2016.
Tim Elliott is currently chair of a Tyne Rivers Trust initiative to improve interpretation at the site, which is attracting locals and visitors to view the annual fish migration and the new fish pass.