Completed works sees Llanfair Talhaiarn flood defences strengthened

A North Wales community’s resilience to flood risks has been strengthened following recently completed work to improve local flood management assets, Natural Resources Wales (NRW) can confirm.

Work on the Nant Barrog flood risk management assets at Llanfair Talhaiarn included strengthening the riverside walls and channel structure and installing a screen at the culvert inlet, a more efficient coarse (tree catcher) screen upstream as well as newly refurbished monitoring equipment.

These works now ensure that the Nant Barrog culvert system is now working as efficiently as it possibly can, maximising the volume of water and river flows that can be accommodated and increasing the standard of protection to residents.

Sara Pearson, NRW Operations Manager (Flood & Water Management), said:

“We are glad to have completed the latest round of works at Llanfair Talhaiarn. This will improve the community’s resilience to flooding as it becomes an ever-increasing challenge.
“The new screen at the culvert inlet will improve efficiency and be easier to maintain. It will also better allow material deemed not to be a blockage risk to pass through the culvert.
“The recently strengthened riverside walls will help keep more water in the channel and make full use of the culvert’s capacity. The channel structure has been strengthened and made more resilient to erosion to help reduce the risk of collapse in the future.
“Thanks to the new coarse screen, larger material will now be held back to reduce the risk of blockage. This will also help to better control the flow of the river during flood events.”

The completed works delivery phase included a six-week delay in May 2022 due to a nesting pair of grey wagtails. The pair was spotted entering the Water Street culvert and an ecologist later confirmed they were nesting. This saw an exclusion zone put in place for the required duration.

The work was completed by a project team consisting of William Hughes Civil Engineering Ltd, AECOM Design consultants and NRW officers. 

Sara Pearson added:

“We must remember that as climate change intensifies, we will experience more extreme weather events, including intense wet periods. This makes flood risk management an increasing challenge for the years ahead.
“Impact of the storms in 2020 and 2021 demonstrates the challenges of a changing climate and the ongoing risk to the Llanfair Talhaiarn community.
“We wish to thank the local community for their patience during the recent works and continue to encourage residents to sign-up for The Early Warning Service (Nant Barrog Alarm 1 and 2) to help with flooding preparation in the future.”

To register for the Early Warning Service or for further information about our work at Llanfair Talhaiarn, please email