How resilient are Natural Flood Management systems?

We are supporting research at Leeds University by Zora van Leeuwen, who presented her poster A Method for Assessing the Resilience of Leaky Dam Networks at the 21st River Restoration Centre conference.

Zora took a novel approach to estimate the probability that leaky in-stream barriers, installed within Natural Flood Management (NFM) projects, might fail during high flow events. Reasons for failures can include hydraulic forces and erosion. The analysis is based on observations from Zora’s own field experiments, combined with data from leaky dams at 15 other sites.

A relatively small number of leaky barriers have failed in several of the NFM projects Zora looked at. The results of the analysis show that the probability of failure can be estimated from these observations as a function of the relative extremeness of high flow events. The failure of an individual leaky barrier may be quite an unusual and unpredictable event, so this probabilistic approach will help in quantifying the resilience of whole systems of NFM assets. This is something we have also been working on, with the aim of understanding NFM systems in a risk-based framework to assess their resilience and flood risk reduction benefits as they increase in scale.

Click the image below to see the poster.

Zora van Leeuwen's poster on leaky dam resilience