Rijkswaterstaat (RWS, an operational department of the Netherlands Ministry of Infrastructure and Water Management) is responsible for the kribben (groynes) along the major rivers in the Netherlands. These are a type of groyne for erosion control. RWS has started a pilot project on the river IJssel with an innovative type of flexible and semipermeable kribbe which promises to reduce costs, bring environmental benefits and be more resistant to impact by ships. The works will be carried out by international construction company BAM and dredging company Van den Herik and the project will be monitored by research institute Deltares.
We will use our recently completed the Phoenix preproduction version to survey this challenging river at regular intervals and monitor the riverbed morphology for 18 months. This will be an excellent opportunity to test it in a range of weather conditions, in strong currents and in the presence of other shipping.
Update: February 2021
We have now completed over fifteen surveys of two stretches of the IJssel for this project. The Phoenix did a great job, despite the sometimes challenging environment. In addition to surveying the riverbed morphology we also surveyed the kribben and erosion control screens, using sonar below water and video and Lidar above water. Because of the stability of our vessel the data was of a high quality and needed very little postprocessing before we handed it over to research institute Deltares for analysis.
During some of the surveys the Phoenix navigated autonomously using radar and AIS, anticipating the movements of other ships. Of course, we were standing by to intervene manually, but this was never required. The whole project was an excellent demonstration of the versatility and reliability of our product. It also provided input for the regulations the Dutch authorities are developing for autonomous vessels.