Salmsteke Hekwerk Hydrologie

More sophisticated subsurface model for future Delta challenges

One of the biggest challenges facing the Netherlands in the coming years is protecting the country from flooding. This is a complex problem that calls for close cooperation and innovative solutions. On behalf of the Netherlands Ministry of the Interior and Kingdom Relations, Geodan presented a highly sophisticated subsurface model (developed by TNO, the Netherlands Organisation for Applied Scientific Research) during the 10th Delta Conference.

Access to subsurface data is vital when it comes to developing, managing and operating our national road system, waterways and water bodies. Data sourced from the Subsurface Key Register (Basisregistratie Ondergrond) helps you visualise a coherent image of this subsurfacein 3D. This ensures that the subsurface is transparent, clear and accessible for all users. The Netherlands is the only country in the world to use this type of detailed model.

Working on innovation together

However, the use of the subsurface model prompted new questions – questions which would have been even easier to answer with a more sophisticated subsurface model. This is why the Netherlands Ministry of the Interior and Kingdom Relations commissioned Geodan and its innovation partners (TNO, Utrecht University and the Stichtse Rijnlanden district water board) to improve the current subsurface model.

Faster and better

The new process allows for a far more efficient interpretation of the subsurface. How was this subsurface created? And which parts are located where? But it also actually contains significantly more data. Whereas collecting data on the local situation used to be very time-consuming, this data can now be sourced directly from the model in any location. These insights make it easier to tailor the design of dikes more accurately to the composition and properties of the subsurface.

Attendees at the Delta Conference got a chance to look at this sophisticated subsurface model: a journey through the subsurface, as it were. Is this good enough, and will this make us better equipped to solve the local security challenge?
This is certainly the case, as it marks a giant leap forwards!

Peter de Graaf

Want to know more?

Peter de Graaf.jpg

Please feel free to contact us. Peter de Graaf is our expert in this field.

Email me

Immense sophistication

The collection of an impressive amount of data has resulted in this highly sophisticated representation of the subsurface. By way of clarification: this representation normally consists of layers measuring 100 x 100 x 0.5 and containing soil types such as clay, peat and sand. The first step was to create a more refined model measuring 25 x 25 x 0.25 metres for a section of the Lekdijk dike (Salmsteke, approx. 3km in length). This is 32 times more refined than the previous model.

Salmsteke Xy Profiel

Salmsteke, a section of the Lekdijk dike, is represented in the refined subsurface model.


Geodan has two branches in the Netherlands

One location in Amsterdam and one in 's-Hertogenbosch. The general mailing and visiting address is President Kennedylaan 1, 1079 MB Amsterdam.


GPS Lat/Lon:Geodan ‘s-Hertogenbosch
51.69174 5.299683
GPS Lat/Lon:Geodan Amsterdam
52.342346 4.91305

Geodan ‘s-Hertogenbosch
Buitenhaven 27-A
5211 TP ‘s-Hertogenbosch
 +31 (0)73 – 6925 151


Geodan Amsterdam
President Kennedylaan 1
1079 MB Amsterdam
 +31 (0)20 – 5711 311