Scheme to aid natural fish passage at weir

A weir on the River Loughor which was restricting fish from reaching breeding grounds has been specially adapted as part of a river restoration programme across Wales.

For many years, fish travelling upstream from the sea found it very difficult to pass over the concrete weir at Ammanford, which sat approximately a metre above the river level.

Now, a series of smaller, manageable steps have been installed leading into the weir to allow safe passage for migratory fish species such as salmon, sea trout eels and lamprey. This has reduced the head difference to less than 30 cm.

Legacy

The weir itself was not suitable for removal, as it supports a river gauging station, and a sewer pipe running underneath.

Dave Charlesworth, Lead Specialist Advisor, Freshwater Fisheries from NRW said: “Many years ago, weirs were commonly installed into rivers for a variety of reasons, but they leave behind a legacy of fragmented rivers and lost valuable habitat for fish.

“Our work to adapt the Ammanford weir has improved fish access to around 20km of new habitat in a prime location for spawning grounds which will benefit salmon and other species.

“The project is part of our wider river restoration programme in Wales, which aims to restore natural river processes and reintroduce habitat which has been lost due to historic human activity.”

Salmon “at risk”

Salmon populations in Wales and across the UK are under increasing pressure due to a number of factors including climate change, water and habitat quality.

On most rivers in Wales, populations of Salmon are now formally classified as ‘At Risk.’

Physical modifications to rivers, such as weirs, remain the number one reason why many rivers are failing to meet good ecological status, due to the impact they have on habitat and species.

The project at Ammanford has been funded by the Welsh Government’s Water Capital Programme and cost approximately £350,000.

This financial year NRW has committed to spend £15m through the Water Capital Programme, which supports a number of environmental priorities including river restoration, metal mine remediation, fisheries and water quality.