New research, led by scientists from Cardiff University and the University of Worcester, has unveiled a promising flood management strategy: natural river barriers made from organic materials like trees, logs, and leaves. These ingenious “leaky barriers,” designed to mimic beaver dams, have demonstrated their ability to mitigate flooding in high-risk areas. Unlike previous studies that relied on assumptions, this research collected real data from 105 leaky barriers spanning a Shropshire river over a two-year period.
The impact of these barriers was substantial. They stored enough water during intense weather events, such as Storm Dennis, to fill four Olympic-sized swimming pools. These barriers effectively raised water levels by up to 0.8 meters, significantly slowing down river flow for approximately seven to nine days. This gradual release of water proved crucial in protecting downstream communities from flooding.
Dr. Catherine Wilson from Cardiff University emphasized the urgent need to combat escalating flood risks, driven by climate change. The study's innovative approach utilized monitoring equipment on three leaky barriers to measure their effects on water levels both upstream and downstream. Additionally, drone images provided accurate measurements of land elevation covered by trees and flora.
This research marks a significant step forward, providing quantifiable evidence of nature-based solutions to address flood events. Leaky barriers prove most effective in narrow channels with steep banks, particularly during smaller storm events. They serve as a cost-effective flood defense strategy, with prices ranging from £50 to £500 per barrier, while also promoting biodiversity in rivers and nearby lands.
The study's impact goes beyond academia. It informs ongoing collaborations with local authorities to identify optimal sites for implementing leaky barriers. By targeting these locations, flood risk to downstream communities and landowners can be substantially reduced.
The findings are poised to influence governmental and industrial efforts in crafting flood defense strategies. They offer insights into safeguarding against both frequent, smaller storms and larger, more devastating ones. Ultimately, this research not only safeguards communities but also underscores the potential of eco-friendly solutions to mitigate the growing threats of flooding.
Source: Cardiff University