Guide for Supra-regional Stress Tests for Pluvial Flooding

In 2021, extreme rainfall in Limburg led to pluvial flooding and even river flooding. This made clear that we also need to tackle climate adaptation at the supra-regional level. Only then can we prevent flooding in places where cascade effects or cross-border impacts can occur. This guide sets out the main principles for this. In doing so, it lowers the threshold to get started and brings parties together.

For whom?

The guide is intended for provinces, district water boards, Rijkswaterstaat, municipalities, central government, safety regions and managers of critical infrastructure.

How can the guide be used?

This guide helps you to conduct stress tests for a supra-regional event. A supra-regional event means extreme rainfall and pluvial flooding across a very large area, such as in July 2021 in Limburg and parts of Belgium and Germany. A ‘supra-regional stress test’ takes you through a number of steps to identify where vulnerabilities and bottlenecks may arise during extreme rainfall in a large area. The supra-regional stress test forms the basis for a risk dialogue. Together with the dialogues at the local and regional levels, this risk dialogue should lead to coherent implementation agendas. The supra-regional stress tests should be conducted about a year before the local and regional stress tests. That way, they can add depth to the local and regional stress tests.

Who has developed the guide?

HKV and ORG-ID drew up this guide on behalf of a consortium that also includes Tauw and APPM. A steering committee supervised their work. This committee included representatives of the Directorate-General for Water and Soil (DGWB), Rijkswaterstaat Water, Traffic and Environment (RWS-WVL), the Dutch Water Authorities (UvW), the Association of Provinces of the Netherlands (IPO), the Foundation for Applied Water Research (STOWA), the Delta Programme Commissioner’s staff, Deltares, Climate Adaptation Services (CAS), Waternet, and the provinces of Limburg, Noord-Holland and Zuid-Holland. They also used input from the Community of Practice ‘Supra-regional analyses of pluvial flooding’. This is a user group of more than 75 organisations that contributed ideas for the guide.

Date of publication

January 19, 2024