A ‘tree catcher’ made up of seven poles staggered across a river is helping protect nearly 500 properties from flooding.

Natural Resources Wales (NRW) has completed a project to reduce the risk of flooding to properties in Cardiff, Wales. The scheme involved constructing the tree catcher upstream of where the River Ely passes under a bridge to reduce the chance of trees and other large objects getting trapped underneath.

At its peak in 2008, river flows would fill an Olympic swimming pool every 20 seconds. The bridge, on Cowbridge Road West, is a known pinch point and partial blockage of the structure could lead to flood water backing up and overtopping the riverbanks, which has previously contributed to the flooding of homes.

In September 2008, some 27 properties were inundated. More recently properties flooded in 2011, 2012 and 2020.

The tree catcher solution consists of seven poles staggered across the river, spaced widely to target large debris that would otherwise be trapped at the bridge. As water levels rise during heavy rain, debris trapped by the poles will float on the surface, allowing water to pass beneath and continue downstream.

By trapping debris at a safe location upstream of the bridge, the risk of flooding is reduced.

Michael Evans, NRW’s head of operations, said: “The tree catcher is an innovative way to reduce the risk of flooding to the residents of Cardiff.

“We’ve all seen the recent devastation that flooding has caused to people’s lives across Wales. Two years on from the devastating February 2020 storms, the impacts of the floods were felt right across Wales and are still etched in our minds.

“Climate change will bring more frequent extreme weather and flood events. While we can never prevent all flooding, we will continue to invest the funding we receive from Welsh Government to manage Wales’ flood risk in the best possible way, working closely with local communities to identify the best combination of measures that tackle the specific threats.”