Reducing risks caused by extreme weather with nature-based solutions

8 min readJan 10, 2023

Nature often suffers damage caused by extreme weather such as storms, heavy rainfall, floods and droughts. But nature itself can also be part of the solution by reducing the impact of extreme weather and climate change. A large EU-funded project aims to increase knowledge about, and the use of, nature-based solutions to reduce hydrometeorological risks.

Large-scale nature-based solutions (NBS) include measures such as detention and retention basins, wetlands and floodplains, restored or new forests, terraces and retaining walls, mangroves, mudflats and dunes and are used in many places, including urban, rural, mountainous and coastal areas. Compared with pipelines, reservoirs, brick walls and dikes — known as grey infrastructure — NBS offer more environmentally sound, socially acceptable and economically viable results. However, applying such solutions on a large scale can be challenging as governments, residents, businesses, activist groups and non-governmental organizations have different, and sometimes even conflicting, interests. The RECONECT project, now in its fifth year, aims to implement and upscale the use of NBS.

Map of RECONECT NBS sites around the world. The project brings partners with experience of successful NBS implementation together (demonstrators) with partners who aim to introduce NBS, but lack the needed resources and methodologies (collaborators). — Copyright: IHE Delft

Co Verdaas, chairman of the Rivierenland waterboard in the Netherlands, stressed how complex reaching public acceptance can be as he opened the project’s 8th General Assembly, attended by 60 representatives from 34 partner organizations across Europe and beyond. Verdaas was in charge of dike maintenance in the Netherlands’ biggest NBS project to date, Room for the River , which concluded in 2016.

“In the Netherlands, I face the fact that people and businesses do not blindly accept anymore what the water authority advises,” he said, adding that authorities in the past simply issued instructions, without consulting and engaging those affected by the actions. “We learned that we need to engage people — but it is complex to really include them in our processes.”

Twinning: learning and reflecting together

RECONECT brings partners with experience of successful NBS implementation together with partners who aim to introduce NBS, but lack the needed resources and methodologies. Together, the two groups co-create knowledge by means of twinning. The experienced partners assist with planning, selection, design, construction and maintenance of NBS. During the three-day General Assembly in November 2022, twinning partners presented progress, lessons learned and needs to successfully implement NBS sites.

Jasna Plavsic, Associate Professor at the University of Belgrade, shared insights from the perspective of partners seeking to develop NBS.

“Most of us experience floods as the main risk. Others have landslides due to floods, or droughts. One of the main RECONECT project goals was to build a worldwide network of these kinds of cases. After that we assessed what their needs where and what kind of measures are in place already,” she said.

“Local authorities for example, are not going to remove dikes to start a NBS site there. Assessing existing knowledge means that we don’t have to start from scratch.”

Man-made terraces maintenance and recovery allow reducing erosion along steep slopes, mitigating the hazard induced by shallow landslides triggering. Terraces recovery is a soil and conservation NBS measure (Portofino Park, Italy) — Copyright: Guido Paliaga, researcher and consultant for RECONECT

Because RECONECT is a large project, it partners very different phases of the NBS implementation process, which can be a challenge, Plavsic said.

“It would be useful if the more experienced partners can share with us how they began, as they’re often already at the end of the implementation phase, and we are just starting,” she said.

Protecting the salt marshes of Europe

Denmark’s coastline accounts for almost 80% of the salt marshes of Europe, and the country is determined to protect these important areas, which are threatened by climate change. Unless space is reserved to allow the salt marshes to adapt to rising sea levels, the marshes could disappear completely.

Lars Kildahl Sønderby, project manager for the Odense municipality in Denmark and a RECONECT participant, shared lessons-learned:

“People living in areas prone to flood risks have to deal with this, but flooding is also a risk for nature. To be called a nature-based solution, there has to be a significant benefit for nature in it,” he said. “We therefore moved some of the dikes away from the coast, which reduces the risk of flooding. From a landscape perspective, we try to keep our coastline as undisturbed as possible.”

Engaging local communities to change to nature-based solutions is a question of land-use privileges: how are residents using the land? Have several generations been farming in a specific area? Changing land use can lead to resistance from land owners and residents in the area.

“In our NBS project in Odense, land owners refused to participate in discussions, as they did not want to give up their way of using the land. But it is also a political discussion: how do we prioritize the land we have?

It will become harder to produce food in these areas where we are not only facing sea level rise, but also a rising groundwater level. From a societal point of view, it would make more sense to change how land is used,” Kildahl Sønderby said, adding that in his view, the land no longer is suitable for intensive agriculture .

Seden Strand, Odense, Denmark, a large-scale NBS in the RECONECT project. The existing dikes were relocated to the higher grounds and meanders were re-created to enhance the natural hydrology and achieve higher standards of flood protection. In addition, the area serves as a habitat for toads and migrating birds and features a bird observation tower and trails, thereby increasing the recreational value of the area. — Copyright: RECONECT

Interactive sessions with citizens help to create ownership

Christian Ebel, representative from the Hamburg project team shared a recent experience of successful stakeholder engagement. At an event with Hamburg residents, he explained what NBS are and where they already exist in the city. He then asked the participants to write down their thoughts and opinions based on a set of guiding questions, which were then grouped in four areas: policy, nature, urban and economy.

“They told me this was the first-time that public administration asked them to participate in an event where their voices could be heard. They realized our project contributed to something positive regarding safety against floods. Creating ownership with people actually living in the area is very important. This can only be achieved if you create an opportunity for opinions to be heard and acknowledged,” he said.

Room for the River: the creation of a pride-evoking solution

The largest NBS project in the Netherlands aimed to achieve flood safety for 4 million people living along the river banks. Eight provinces, 12 water boards and many local communities successfully lowered flood plain levels, created water buffers, increased the depth of side channels and constructed flood bypasses as part of the project, which concluded in 2016. In Nijmegen, a city in the east of the Netherlands where the RECONECT General Assembly was held, was particularly vulnerable to flooding as the Waal river makes a strong curve right behind the city centre .

The river Waal with on the left the extra space for the river with high water, on the right the city of Nijmegen, the Netherlands — Copyright: IHE Delft

Carsten Schipper Hein, stakeholder manager during the project highlighted how he engaged with affected communities in all phases of the project.

“My biggest challenge was that we had to move 200 households and 50 companies from the area where we wanted to create more space for the river. We talked to every single one of them, offering a good price. This is a time-intensive process with a huge impact for the people living there, but very necessary for the project’s success,” he said.

“What I learned is that however big a project is, it’s still a human project, built by real people. We put the construction workers and others involved in the spotlight to create understanding about the people behind this. We also taught residents how to read maps, so that they could help us solve problems. We connected them with the bridge designers at an early stage, so that they could bring in their ideas. When working with residents and businesses in such a large project, I learned to take a step back and ask myself: am I right or am I wrong?”

The mirror bridge, co-designed by the citizens of Nijmegen — Copyright: IHE Delft

NBS site visits

Some General Assembly participants visited Dutch NBS sites, including the Sand Motor , a large man-made sand peninsula that will protect the nearby coast from the sea for the next 20 years. Currents, wind and waves gradually spread the sand along the coast and into the dunes. This cost-effective solution means dredging new sand every year is not needed, giving the bottom of the sea time to restore itself from the sand collection.

The Sand Motor behind the dunes of The Hague, The Netherlands — Copyright: Adam Mubeen, PhD Candidate at IHE Delft

Zoran Vojinovic, Associate Professor of Urban Water Systems at IHE Delft and RECONECT project leader finds the variety of Nature-Based Solutions demonstrated within the RECONECT project a great example of how to design such solutions in a multifunctional way. In particular, stimulating the co-creation of land use planning by linking the reduction of hydro-meteorological risk with local and regional development objectives in a sustainable and financially viable way, is an added value.

“What is crucial for our team is to gather detailed information, qualitative and quantitative data from all demonstration sites in a way that can serve researchers, practitioners and policy makers in advancing their understanding of NBS. We are carefully addressing strengths and weaknesses of all our NBS sites for the purpose of developing design standards and guidelines. We are also facilitating exchange of knowledge, capacity building and dialogue between different stakeholders. This process aims to capture the current knowledge of NBS, and facilitate upscaling of NBS globally,” he said.

More about RECONECT

The European Union-funded RECONECT project (Regenerating ECOsystems with Nature-based solutions for hydro-meteorological risk rEduCTion), coordinated by IHE Delft, is an interdisciplinary international project that aims to contribute to the EU reference framework on NBS by demonstrating, referencing, upscaling and applying large-scale NBS in rural and natural areas. RECONECT stimulates a new culture of co-creation of land-use planning that links the reduction of hydro-meteorological risk with local and regional development objectives in a sustainable and financially viable way. RECONECT carries out the co-creation process in a manner that deliberately addresses water, nature and people in NBS implementation.

The next General Assembly is set to take place in May 2023 in Hamburg, Germany.

Group photo of RECONECT partners at 8th General Assembly, November 2022. — Copyright: RECONECT




The RECONECT project demonstrates the effectiveness of Nature-Based Solutions for hydro-meteorological risk reduction in rural and natural areas