Challenge 1: Scientific Evidence Estuaries, Rivers and Lakes

There is a frequent lack of knowledge on system performance (especially in extreme conditions), and how best to select Key Performance Indicators for monitoring after implementation. We have managed and investigated this challenge through several methods, which you will read more about here.

The effectiveness of Building with Nature – Evidence from catchment projects

Building with Nature (BwN) measures are defined as measures inspired by nature, which are resource-efficient, resilient to change and able to address societal challenges while providing several environmental and societal benefits (co-benefits). They are applied in catchments of different scales, varying from small ones, such as the Råån in Sweden or the Kleine Nete in Belgium, to middle ones, such as the Eddleston in Scotland, to large ones like the Rhine in The Netherlands. The challenge is to provide the empirical basis for assessing the cost, effectiveness and impact of flood risk on restoring the river through BwN at the different catchment scales. The projects in the different countries contribute to scientific evidence that in many cases BwN is more resilient and leads to a more sustainable catchment than using grey or green-grey solutions.

More information on Building with Nature at catchment sites read the factsheet Demonstrating Building with Nature at catchment sites (pdf, 266 kB)

Lack of scientific evidence

The aim is to assess the effectiveness of BwN measures (sometimes also called Natural Flow Management, NFM), to reduce flood risk and improve river habitats, whilst at the same time working with communities and local stakeholders to maintain a sustainable environment as scientific evidence for effectiveness of BwN techniques is currently lacking. Adding evidence will stimulate local to national authorities to take BwN measures along in their assessment of flood risk reduction measures.


The method used in this project was a combination of very different approaches. In Scotland, the approach was an empirical one, with the focus firmly on collecting quality-assured data derived from a detailed network of hydrological and ecological monitoring stations and surveys across the whole catchment. Monitoring and hydraulic and morphological modelling also was an important aspect of the Dutch approach. In Sweden, the focus was on ecological monitoring and modelling, while in Belgium stakeholder involvement turned out to be an important instrument to get sufficient support.

Still in progress

At this moment, the research is still in progress and therefore it is not possible to draw conclusions yet. More information will be published as soon as the research is finished. We expect this to be around July 2020.