Approach to pluvial flooding in the municipality of Enschede
In 2015, the municipality of Enschede began drafting a new basic plan for its sewer system in order to prevent pluvial flooding in the future.
In the recent past, the city of Enschede has been confronted with local pluvial flooding. The photographs below show several examples of flooding in the city.
The new sewer plan takes a risk-based approach to pluvial flooding. A risk analysis of pluvial flooding was drafted for this purpose. The aim of this risk analysis is to enable officials to take effective, specific policy decisions.
In the risk analysis, the level of risk attached to a location is established by analysing the types of effects and the frequency of flooding. Subsequently, the most effective measures are identified and the risk remaining after the implementation of measures is assessed. This method is based on a method developed by Stowa and Stichting RIONED (see download).
Results
The risk analysis has identified various bottlenecks. The city has drafted different measures to combat pluvial flooding at these locations. The aim of these measures is to decrease the risk of pluvial flooding sufficiently and at the lowest possible cost, even in the situation as it will stand in 2050 as a result of climate change.
Several measures that have been drafted are listed below:
- building a drainage-transport system for the city districts of Pathmos and Stadsveld, and disconnecting more than 50 hectares of paved surface in public areas. Speed bumps will be adapted so that they do not form an obstacle to the flow of surface water and above-ground water storage will be built;
- for a number of pluvial flooding locations, the ground level has been/will be lowered and surface drainage routes will be built to transport rainwater to retention areas;
- building two urban channels to drain groundwater and to drain some rainwater during extremely heavy downpours;
- building a bypass next to a rainwater storage and settlement basin;
- building an underground storage facility in combination with adapting the slope of the ground surface in public areas;
- traffic facilities and closing the tunnel when it floods.
Contact person
Erik Dekker
Witteveen+Bos
+31(0)6 - 86 81 07 71
erik.dekker@witteveenbos.com