New story map provides insight into cascading effects of extreme weather
What happens when major roads become flooded during prolonged periods of extreme rainfall? Can power installations, hospitals, and other critical facilities still be reached? A new story map in the Dutch Climate Impact Atlas (Klimaateffectatlas) shows how disruptions to the road network can affect other vital services. The story map was developed by Deltares in collaboration with the Dutch Ministry of Infrastructure and Water Management (IenW) and Climate Adaptation Services (CAS).
Go to the story map: “Accessibility of Critical Infrastructure”
From flooded roads to cascading impacts
Dutch society depends heavily on critical infrastructure such as energy, telecommunications, drinking water, and healthcare services. These systems are interconnected. When one part fails, the consequences can spread to other sectors. These knock-on impacts are known as cascading effects. Extreme weather increases the likelihood of such chain reactions.
For example, flooded roads may prevent access to critical facilities for inspections, maintenance, or emergency repairs. Emergency services, suppliers, and employees may also experience disruptions. The new story map in the Climate Impact Atlas makes these indirect impacts visible.
From surface flooding to societal consequences
The story map illustrates how accessibility changes during a large-scale extreme rainfall event. It uses maps from the Supra-Regional Stress Test (Bovenregionale Stresstest), based on a rainfall scenario comparable to the conditions experienced during the 2021 floods in Limburg.
The analysis was conducted using RA2CE (Resilience Assessment and Adaptation for Critical InfrastructurE), an open-source platform developed by Deltares to assess the vulnerability of infrastructure networks. This approach reveals how extreme rainfall affects accessibility and what consequences this may have for critical services that depend on the road network. The maps show where accessibility declines, which alternative routes remain available, and where areas may become isolated.
Supporting the CER resilience challenge
The story map was developed to support the implementation of the Critical Entities Resilience Act (CER) and its Dutch implementation through the Critical Entities Resilience Act (WWKE). The legislation requires providers of critical services to assess risks to their operations and take measures to strengthen resilience. This includes not only direct climate-related impacts, but also dependencies on other systems and infrastructure.
The story map provides a practical foundation for risk assessments, stress testing, emergency preparedness, and the further implementation of resilience requirements. Safety regions, infrastructure operators, and public authorities can also use the maps to identify vulnerabilities and support discussions on resilience.
Disruptions to the road network can reduce the accessibility of critical locations.
A practical tool for critical infrastructure operators
Because the locations of critical assets are often confidential, the story map is designed so that organisations can combine the accessibility information with their own data. This enables them to assess which facilities, substations, healthcare sites, or other critical assets may become less accessible during extreme weather events.
The information helps organisations identify vulnerabilities, develop contingency measures, and strengthen the resilience of their services.
“Cascading effects often arise through dependencies that are not immediately visible. Accessibility is a good example. By providing insight into the accessibility of locations, this method helps organisations prepare more effectively for disruptions caused by extreme weather,” says Margreet van Marle, climate resilience expert at Deltares.
This method helps organisations prepare more effectively for disruptions caused by extreme weather.
Margreet van Marle, Deltares expert
From research to application
The story map builds on earlier Deltares research into the cascading effects of extreme rainfall on critical services. The underlying methodology was developed to better understand how accessibility disruptions can affect other critical sectors and societal functions.
With this new story map, that knowledge is now made accessible to operators of critical infrastructure, safety regions, governments, and other organisations working on climate adaptation and resilience.
This methodology is of great value for the development and revision of crisis plans and for prioritization during such scenarios.
Jasper Luiten, Ministry of IenW
"The scalable methodology in this map story helps providers of vital infrastructure look beyond the immediate effects of large-scale extreme rainfall; it also enables them to assess the consequences regarding access to critical assets and dependencies on other vital functions. This can be of great value for, among other things, developing and revising crisis plans and establishing priorities during such scenarios," says Jasper Luiten, Ministry of Infrastructure and Water Management.
