Barrier removal project at Co Wicklow’s Ballinglen River completed

Since 2020, the East Wicklow Rivers Trust (EWRT), Wicklow County Council (WCC), Inland Fisheries Ireland (IFI), and Local Authority Waters Programme (LAWPRO) have been working together in partnership to improve habitat and biodiversity for migratory fish in rivers and streams in Co. Wicklow – 'Wicklow Fish Barrier Mitigation Programme'. The project has also been supported by local riparian landowners and National Parks and Wildlife Service.

In 2012 Inland Fisheries Ireland completed a survey of barriers to fish migration on rivers in County Wicklow. The scale of the problem was highlighted in the Avoca Catchment which showed that approximately 50pc of the entire catchment is potentially impaired by man-made structures, with fish migration either partially or fully blocked. One of these is at Ballinglen Bridge on the Ballinglen River, which is located between Aughrim and Tinahely villages. The Ballinglen River is a tributary of the Derry Water River, which joins the Ow River to become the Aughrim River and the barrier at Ballinglen Bridge was identified as a priority for action.

The Ballinglen Bridge is a beautiful three-arched stone bridge built circa 1790. It is constructed of local shale with lime mortar and cut stone granite voussoirs. The floor bed underneath each archway of the bridge is laid with cut granite stones which are perfectly laid and grouted.

Unfortunately however this man made structure creates a barrier to fish migration for fish species such as the Atlantic Salmon, Sea lamprey, River Lamprey and the Brook Lamprey, which is also a species in trouble. All of these species, with the exception of Brook lamprey, are diadromous, in that they travel between the sea and freshwater habitats where they spawn and a new generation begins life all over again. When migrating over large distances in rivers they inevitably encounter barriers to free movement which, as in the case of the Ballinglen Bridge prevents them from reaching their spawning grounds in the pristine habitat upstream.

Recognising the built heritage of the bridge, WCC carried out all necessary heritage and archaeology studies and reports and the East Wicklow Rivers Trust received funding from the IFI Salmon and Sea Trout Rehabilitation, Conservation and Protection Fund 2021 for the project and engaged RIVUS Ecological Engineering to complete an Ecological Impact Assessment Report, an Appropriate Assessment Screening Report and to design the fish pass and lamprey and eel pass.

In 2024 the project was given the green light to proceed. IFI staff completed a pre-construction fish survey and water quality monitoring has been ongoing by WCC staff. Following a competitive tender process RIVUS Ecological Engineering were appointed to construct the rock ramp and these works are now substantially complete.

Deputy Jennifer Whitmore, who is the Social Democrats spokesperson on biodiversity, has commended all the participants in the project and has hailed Wicklow as a leader in improving fish migration in Ireland's rivers.

She said: "The work done by East Wicklow River's Trusts on this project has been immense. It is wonderful to say that Wicklow is leading the charge to improve the quality of fish migration patterns in Irish rivers.

"What is happening across Ireland's network of rivers and streams is very worrying, but the work done in Tinahely is an example of us getting it right. The initiative has seen the completion of a barrier modification programme for the Derry Water River at Ballingen Bridge near Tinahely. Using local stones to create a rock ramp under the bridge will open breeding grounds for upstream migratory fish.

She added: "I have been involved in a groundbreaking project in Wicklow, led by the East Wicklow Rivers Trust, in partnership to set this right in Wicklow. Also, the tremendous work of Alan Sullivan, from Rivus Ecology, who the East Wicklow Rivers Trust hired, must be acknowledged.

"This is just one local example of what needs to be done nationally. I hope that as other counties move to improve the migration of fish species in rivers around the country, they will use the approach adopted here in Wicklow as a template, as it has been a wonderful success."