Project set to re-wiggle city’s river

A project is currently underway which aims to ‘re-wiggle’ and reconnect a Cardiff stream to its historical channel and floodplain and encourage the reintroduction of salmon, eels and trout.

The Nant Dowlais – a tributary of the River Ely outside Cardiff – is currently failing to achieve ‘good’ status under the water framework because of phosphate and a lack of fish.

The main reason for this is the historical legacy of the natural river course being straightened in the late 19^th century.

This has resulted in natural gravel banks being eroded with a resultant increase in sediment in the water but now, a £583,500 project funded by Welsh Government and carried out by Natural Resources Wales, aims to turn things around.

Reconnection

It is the largest project of its kind in south Wales and aims to reconnect the river to its historical channel and floodplain, having been disconnected and straightened in the past.

The channel has been re-engineered to replicate its original route, a process known as re-wiggling, which sees more natural curvature reintroduced to better follow the contours of the land.

This process will add around 200 metres in length to the Nant Dowlais and the scheme itself will cover more than 750 metres of channel, restoring it to its natural condition.

New fencing will allow riparian vegetation to flourish and a new cattle drinking bay will prevent cattle from entering the stream directly and reduce the risk of erosion to the channel.

New bridge

A new, free-spanning bridge will replace a failing access culvert, improving connectivity upstream.

Speaking on a visit to the river, Deputy First Minister with responsibility for Climate Change, Huw Irranca-Davies said: “I am delighted when we can fund projects like this which make a real difference to our rivers and people’s lives.

“We are fully committed to improving water quality and restoring our rivers.  I’m hopeful that the lessons we learn from this work on the Nant Dowlais can help inform more projects like this right across Wales.”

McCarthy Contractors – a local company, employed twelve people to work on the project meaning the money was invested in Welsh jobs and skills.

David Letellier, Head of south Wales central operations for NRW added: “The scale and rate of biodiversity loss across the nation is accelerating, and we must take urgent action to secure the future of some of our most iconic and threatened species.

 “This ambitious project aims to bring life back into the Nant Dowlais, while also improving water quality and building resilience to the impacts of climate change in the future.  This is part of a wider Ely Catchment vision to restore ecological resilience throughout the landscape.

 “This is a great example of how we are working towards our corporate plan ambitions to become nature positive by 2030.”