Preparing for floods: adapting the Netherlands for climate resilience

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During the night of 31st of January 1953, a sea storm surge broke through the Netherlands’ protective barriers and flooded roughly 10% of the country; the UK and Belgium were also impacted. In the Netherlands, 1836 people died, and the total cost of damage was equivalent to around €5.4 billion today. Much more recently, in summer 2021, floods caused by heavy rains in the province of Limburg led to hundreds fleeing their homes. With climate change expected to trigger more extreme weather events and raise sea levels by 15-40 cm by 2050, there is a growing need for this low-lying land to plan ahead. Dutch partners in the EU-funded IMPETUS project are developing digital decision-support tools for municipal spatial planners, so they can create more sustainable cities and communities, with a focus on the southern city of Rotterdam and surrounding areas in Rijnmond and the province of Zeeland. Their flooding decision support system will help the region adapt to increasing flooding risks in the face of climate change.

Risks and responses

There are a number of ways in which flood risk is increased due to the climate crisis. Alongside rising sea levels due to melting ice caps, a warmer atmosphere can hold more water which leads to more intense periods of rainfall. Already this decade, one third of Pakistan was submerged during a monsoon season, and German river banks burst killing 220 people in the same incident that caused flooding in Limburg.

“People didn’t know where to go – they didn’t know where to flee, and which areas were safe,” says Fons Nelen, referring to the Limburg floods. He’s the director of Nelen & Schuurmans, a water management consultancy company based in Utrecht. “You can save a lot of lives, and you can prevent a lot of damage, if you have the right information at the right time.”

“Flood risk is always happening very fast,” says Nelen. “So you see a storm coming and you have to know what to do – it’s always a matter of hours.”

Photo of sitting woman and standing man looking at a computer screen
Martine Rottink and Fons Nelen of N&S (© ESCI)
Flood risk map of Rotterdam and environs(© N&S)
Graphic representation of a multi-purpose water plaza in Rotterdam city, NL.
Computer model of a multi-purpose water plaza in Rotterdam (© Rotterdam Climate Initiative RCI)

Developing solutions

As the threat of another countrywide flood rises alongside global temperatures, Dutch engineers like Nelen are working hard to come up with solutions. Within Nelen & Schuurmans, they’re building models that incorporate information about all the ways water moves within the country, from the sea, rivers and sewers, to real-time meteorological information.

Such technology has already been deployed in a warning system in the Parramatta river in Sydney, Australia. “There is a warning level… if it starts raining, people get information when a certain threshold is reached,” he says. “We think that, where every end user nowadays is used to getting weather information, the next step will be that everybody gets information on flood risks.” The World Meteorological Organization agrees, as they advocate for flood risk information for everyone by 2030.

Martine Rottink, a consultant at Nelen & Schuurmans, says that the tool they’re developing –software that will host the models they’re creating – will be used by municipalities, rather than the general public. After developing a demonstration, they recently showed the tool to potential users and are currently implementing the feedback before finalising development. One piece of feedback was that it was nice to have data about flooding, but users need more guidance on practical steps they could take – according to Rottink.

This work is part of the EU-funded IMPETUS research project, which is finding ways to turn climate commitments into tangible actions to protect communities. “We began with the project in 2021, and we are planning to finish in 2025,” she says. In the project, the team is focusing on how to make the city of Rotterdam, its port and surrounding area more resilient to sea level rise.

Practically, Rottink says that the tool can be used to plan ahead when it comes to flood risk. “In the Netherlands, we have put our faith in dikes and barriers to protect us against sea and river flooding and have focused almost solely on flooding prevention,” she says. “But pressure on our system will increase with climate change: to adapt and maintain a safe living environment, we need other safety measures, like robust contingency and spatial planning.”

Planning to prevent problems

Another factor Rotterdam will need to deal with is more intense rainfall. “Because of climate change, we see problems with rainwater in our city,” says Johan Verlinde, Program Director for climate adaptation with the municipality of Rotterdam. “We see that the average annual rainfall is about the same, but it falls in a shorter amount of time, especially in summertime.”

Intense rainfall can overwhelm the city’s sewer system. To stop this leading to flooding, the municipality of Rotterdam has built a number of small reservoirs within the city. These hold water for around 24 hours before releasing it into a chamber where it can soak into the ground and become groundwater, without entering the sewer system.

Such city infrastructure has to be multifunctional. Each reservoir’s design is unique, as the planners take local citizens’ preferences into account. For example, one reservoir can be used for skating and has a space to host performances. “We want to make the city climate proof in a way that’s also more attractive to our citizens,” Verlinde says. “It’s not only about technical solutions below the surface, it’s also about adding small parks or making the buildings more green.”

According to Fons Nelen, urban planners and landscape engineers have been taking climate risks into account only for around the past ten years. Although the chance of flooding is still low – even in the low-lying Netherlands – if it does happen, the impact can be very high, as the floods of 70 years ago and more recently showed. “If we are able, within the IMPETUS collaboration, to demonstrate the use and capabilities of digital decision-support technology, our ambition is to apply it worldwide


High temperatures

Record-breaking summertime temperatures have been recorded in the Netherlands in recent years. With global temperatures rising, such extreme weather events will occur more often, and for longer periods. Prolonged high temperatures, with warm nights as well as hot days, can cause heat stress* and related health issues, particularly among city populations.

*Heat stress occurs when the human body cannot get rid of excess heat and can impact wellbeing through conditions such as heat stroke, exhaustion, cramps and rashes.

"We want to enable municipality decision makers who are working on spatial developments to identify heat stress 'hot spots' and cool areas, analyse the future effects of climate change, and model the effect of different heat stress-reducing measures. The tool must provide them with an easy starting point to integrate heat stress risks in their projects."


Despite the cooling effect of the sea in the region of Zeeland, the growing risk of heat stress has become a concern.

Elderly and other vulnerable people are more impacted by the effects of prolonged heat, which can cause headaches, dizziness, insomnia and other health issues – even death. Excess temperatures also affect general comfort and liveability of cities. Water quality can be reduced, both for drinking and swimming, and infrastructure can be affected. Buildings and concrete surfaces trap heat, potentially leading to damage, and release it during the night, keeping temperatures warm.

During heat waves, it is important that everyone has access to a cool and comfortable place. Appropriate spatial planning can help to decrease and deal with heat stress. Environmental factors like water bodies, trees, and shade have a major impact on stress caused by high temperatures. Therefore, planting trees, removing concrete surfaces, creating green roofs and cool spaces can improve our comfort and health. The IMPETUS Atlantic team is developing a digital tool to support regional decision making for city planning to address these needs.


Flood risk

By 2050, sea-level within this region is predicted to rise by 15-40 cm, with more frequent extreme weather and more (severe) storms triggered by climate change. These changes will exacerbate the natural risk of flooding in the IMPETUS ‘Atlantic’ region, because it is surrounded by rivers and the sea, and is below sea level.

*Risk takes into account two aspects; the chance that an event will occur and the negative impact of such an event once it occurs. When there is a low chance that an event will occur, but its impacts are huge, the risk is still significant.

“In the Netherlands, an extensive system of dikes protects us against sea and river flooding. We have always put our faith in this defence and focused almost solely on flood prevention. However, pressure on our system will increase with climate change and rising sea levels. To adapt and maintain a safe living environment, we should develop other safety measures, like more robust spatial planning and contingency plans."


Rotterdam city, is located in Rijnmond – ‘mouth of the Rhine’. The Rhine river flows through this densely populated area and characterises the region. Protections such as sea dikes and storm surge barriers have been constructed to protect the region, but flooding still occurs.

People living in the city are accustomed to seeing smaller floods. The changing climate affects the interplay between rainfall, river levels and sea storms, increasing the flooding risk. Water levels could rise by a few metres, even in populated areas, with potentially massive impacts. 

Mitigation measures such as storm surge barriers reduce the chance that high water reaches the city, but to minimise the impact of floods when they do occur, adaptation strategies are also needed. A city that can adapt to be safe from floods must be carefully designed. How best to design such an adaptive city?

Critical infrastructure, such as hospitals and evacuation routes, must be accessible at all times. Planning how to best protect them, homes and lives is complex. Flood water behaves in a complex way and flood risks show strong spatial variations. The IMPETUS Atlantic team is developing a digital tool to support regional decision making for adaptive city planning. 


Energy and waste water

To become climate-neutral by 2050, climate mitigation* efforts are crucial in our strategy for how to deal with climate change. Reducing our energy consumption is a significant mitigation step. In the Netherlands, 15% of energy is consumed in the Rijnmond area around the port of Rotterdam, in large part by a major petrochemical industry cluster.

*Climate mitigation encompasses measures such as technologies, processes, or practices that reduce carbon emissions or enhance the sinks of greenhouse gases.


The Rotterdam port petrochemical industry cluster is Europe’s largest. It consumes 70% of the Rijnmond region’s energy. A large part of this energy is wasted (64%, 203 petajoules). More than half of that energy is lost with wastewater. In addition, most energy processes within these industries rely on fossil fuels, which has a significant impact on the climate.

Energy use must be minimised and fossil fuels should be replaced by renewable sources if climate change is to be mitigated. Electrification of processes opens up the possibility to use more renewable energy and can greatly impact decarbonisation. Recovering wasted heat would significantly reduce energy consumption and is a first step towards a more circular industry. 

Supporting industries in a transition towards climate-neutrality depends on identifying how best to reduce their carbon footprint without sacrificing production or performance. The IMPETUS Atlantic team is creating a digital tool that supports decision making about pathways towards an effective energy transition for EU industry.