The Thorn – Wessem project will be definitively prepared and executed by contractor combination MaasZicht. In this combination, Van den Herik – Sliedrecht will work together with fellow contractor Heijmans to realize the project. We are doing this on behalf of the Limburg Water Board. Before the actual implementation of the dike reinforcement and stream restoration can begin, we will first complete the design in collaboration with Waterschap Limburg. This is done with input from the environment.

Early market approach
The Thorn – Wessem project consists of a dyke reinforcement and stream restoration and is still in the planning phase. The Limburg Water Board has produced a design for the project that we are working out for them in the MaasZicht contractor consortium. A few choices remain to be made before everyone has a chance to respond to the Draft Project Decision. For example, at Wessem the outlet of the Thornerbeek into the Maas will be further designed. Other examples are a closed soil balance with the excavation of a new route for the Thornerbeek and the incorporation of the raising of the quay wall at the Maasboulevard in Wessem. The Limburg Water Board chose an early market approach in order to involve our implementation knowledge and expertise as early as possible in the design.

Jeroen Achten, portfolio holder for flood protection and flood defenses at the Limburg Water Board: “We have a big task in Limburg. It is good that now Thorn – Wessem is one step further. With the contractor’s expertise, we expect to be able to submit the Draft Project Decision for inspection this year.”

Bart Müller, director of projects at Heijmans, on behalf of MaasZicht: “Water safety requires robust and future-proof solutions. With this dyke reinforcement, we are combining safety with nature restoration and quality of life. Together with our partners, we are ensuring that Thorn and Wessem are not only protected against high water, but that the area also remains sustainable and attractive for the future.”

The task in Thorn – Wessem
The dike section Thorn – Wessem consists mainly of a green dike except at the Maasboulevard in Wessem where it is a hard barrier. Behind a large part of the dike section is the Thornerbeek. The dike Thorn – Wessem is not strong and not high enough to protect Thorn and Wessem from high water in the future. Because the dike will be reinforced, there is insufficient room for the current narrow Thornerbeek. We are therefore going to divert the stream. In doing so, we have the task of designing it as a nature brook to meet the requirements of the European Water Framework Directive. We will restore lost habitats for aquatic plants and animals in and along the Meuse as much as possible by rearranging banks and stream mouths.

Follow-up
The draft is expected to be finalized and developed into a Draft Project Decision Omgevingswet in the fall of 2025. People can react to this with an opinion and later on with an appeal at the Final Project Decision. Implementation of the dike reinforcement is expected to start in 2027. The plan is for Thorn and Wessem to be flood-proof by 2029!

High Water Protection Program
Dike reinforcement Thorn – Wessem is part of the national High Water Protection Program (HWBP). The largest dike reinforcement operation since the Delta Works. In this program, water boards and Rijkswaterstaat will improve more than 1,400 kilometers of dikes and 400 locks and pumping stations throughout the Netherlands over the next 30 years.