Complex simulations explore inland navigation on the Gelderse IJssel

AuthorsSpronsen, N. van, Doorn, F.

Conference/JournalMARIN Report 144

Date30 Jun 2025

Climate change is causing more frequent periods of drought, leading to low water levels in this river system. This makes it challenging to guaranteeing cargo transport via inland waterways.

The situation of the Gelderse IJssel in the Netherlands is even more complicated due to soil erosion, changing morphological conditions of the bottom, and the shift in discharge distribution (feed of water) between the Waal, Rhine/Lek, and the IJssel. These factors have worsened over the years.

Contact

Nicole van Spronsen

senior project manager

During low river discharges, the available width of the navigation channel of the upstream part of the river between Westervoort and Deventer is locally reduced from 40 m to 25, or even 20 m at some spots. Additionally, the strong meandering character with deep water outer bends and shallow water inner bends make the IJssel even more challenging to navigate under low discharge conditions.

important knowledge for a navigable future

The Gelderse IJssel is a difficult river to model for real-time simulations, given its complex underlying physical phenomena. It is not a canal with a square cross-section. It has a lot of bends, groynes and a sloping bank. This study was conducted on the edge of what is currently possible in real time simulation, and we are proud of the result.MARIN is enhancing its understanding of sailing behaviour on restricted inland waterways to obtain validated results and to ensure our rivers remain navigable in the future.

The skipper's perspective during the simulation

Encountering ships in the Upper IJssel. Created from AIS data from RWS using the temporal controller in QGIS and ffmpeg. Purple ships are sailing with a drift angle, yellow ships are missing the heading and are drawn with the course over ground.