Rijkswaterstaat has initiated a tender procedure for inspecting approximately 270 culverts with a diameter up to 1.5 meters that lie beneath the main road network.
To keep the main road network free from water, connect watercourses, or allow flora and fauna to cross safely, culverts (connections) are located under the road. It is estimated that there are 6,000 such objects under the main road network, many of which were constructed in the mid-20th century.
Currently, there is insufficient information available regarding the status and technical lifespan of the small culverts under the pavement. Over time, these culverts can become damaged, leading to potential collapse or blockages. Such damage can result in waterlogging, subsidence, or even cavities under the pavement.
Development of Methodology by Renewal Program Research
The Renewal Program Research is developing a methodology to determine the remaining lifespan, allowing timely measures to be taken to ensure safe operation. This method is being developed in collaboration with TNO, the regions of Northern Netherlands, Western Netherlands-South, and Southern Netherlands, and the future market party post-tender award.
Data Collection Through Inspection
Approximately 270 culverts will be inspected. The data collected from these 270 inspections will be used by the research program to develop a method for determining the remaining lifespan of small culverts, which is essential for maintaining road safety.
Preparations are currently underway to conduct inspections, and the tender process has begun. Rijkswaterstaat is seeking a party experienced in cleaning, dewatering, and investigating culverts/sewers and familiar with the Soil Quality Decree.
To ensure safe execution, it is expected that this party has experience working on the main road network and in applying for and implementing traffic measures.
Tender
The Small Culvert Inspections project involves cleaning, dewatering, and inspecting about 270 small culverts with a diameter less than 1.50 meters under the main road network. Both conditioning, preparatory, and execution tasks are required. Rijkswaterstaat expects to award the two-year contract in July 2025. Interested market parties can participate in the tender procedure via TenderNed.
Renewal Program Research
In the coming decades, Rijkswaterstaat faces a significant renewal challenge. Due to aging and increased usage, the design lifespan of many bridges, tunnels, viaducts, and locks is nearing its end. The Renewal Program Research is conducting research to better determine the remaining lifespan. The Small Culvert Inspections project is part of this research program.