Three mega-nourishments along the Holland dune coast: a first comparison and appraisal

Theme days
Friday, 17 November
Zuid Hollandplein 1
2596 AW Den Haag, Netherlands

NCK theme day on Friday 17 November 2017: Three mega-nourishments along the Holland dune coast: a first comparison and appraisal

Summary of the day
For the first time, the effects on dunes at the locations of three “mega” nourishments were compared and appraised.  The three nourishments-cum-coastal extensions are, from south to north: Spanjaards Duin (6,6 Mm3 since 2009), the Sand Motor (21,5 Mm3 since 2011) and the Hondsbossche Dunes (40 Mm3 since 2014). Some 12 presenters at the NCK theme day brought their experiences in the political context, morphology and ecology of these projects to the attention of the > 50 heads of public (see link to the presentations in the programme below). Discussions were held to compare the monitoring outcomes of the different sites. Comments were made by the public also in the relation to the effects and to the design of the different nourishments as reasons for the observed differences. In the afternoon we made an excursion to Spanjaards Duin and the Sand Motor in close vicinity of The Hague for hands-on experience. We were very lucky with the weather, and enjoyed the sight of dune development taking place. The common feeling was that in future more meetings will be needed to handle the subject of sediment dispersal into the dunes.  Many thanks are due to the Province of South-Holland (Ben Girwar) for providing the venue for the morning session, the catering and the bus transport.

Groepsfoto Mennobart small


Orginal announcement below

The first evaluation of the Spanjaards Duin nature compensation project is approaching in 2020, the Sand Motor has had its first five-year evaluation in 2016, and the Hondsbossche Duinen project is now in place for almost three years. So far, however, sharing of experiences and insights between these three dune development projects has been limited.

This is a good opportunity to organize an NCK theme day on dune development. During this event, we aim to bring together the NCK and the dune community to compare insights of the three projects described above. Also, the event will facilitate exchange of knowledge between coastal researchers, dune management, industry and stakeholders on geomorphological and ecological processes in Dutch dune systems and the influence of sand nourishment thereon.


09:30 – 10:00 Registration with tea and coffee  
10:00 – 10:05 Welcome Ben Girwar (Provincie Zuid-Holland) and Bert van der Valk (Deltares)
10:05 – 10:50 Spanjaards Duin  
  Introduction (10 min)
pdfAll clear (if time allows): Nature compensation Spanjaards Duin 2009-2033
Mennobart van Eerden (Rijkswaterstaat WVL)
  Morphology (10 min)
pdfMorphological processes in Spanjaards Duin 2009-2017: Building with Nature, but how to continue?
Bert van der Valk (Deltares)
  Ecology (10 min)
pdfTo intervene or not to intervene: Dilemma’s in the management of a dune slack
Stéphanie IJff (Deltares)
  Discussion and conclusions (15 min) Kees Borst (Rijkswaterstaat WVL)
10:50 – 11:35 Sand Motor  
  Introduction (10 min)
pdfIntroduction to the Sand Motor
Sierd de Vries (TU Delft)
  Morphology (10 min)
pdfDune formation at the Sandmotor: expectation vs. reality
Bas Hoonhout (Deltares)
  Ecology (10 min)
pdfEmbryo dune development on the Sandmotor: Implications of mega-nourishment design
Marinka van Puijenbroek (Wageningen University)
  pdfDiscussion and conclusions (15 min) Kathelijne Wijnberg (University of Twente)
11:35 – 11:50 Tea and coffee  
11:50 – 13:00 Hondsbossche Dunes  
  Introduction (10 min)
pdfIntroduction to innovation project HPZ
Sonja Ouwerkerk (HKV Lijn in water)
  Morphology (10 min)
pdfDune development and influences of artificial relief features
Maarten Jansen (Witteveen en Bos)
  Ecology (10 min)
pdfEcology under development at the HPZ
Bert van der Valk (Deltares)
  Discussion and conclusions (15 min)
pdfZwakke schakels
Peter Brandenburg (Van Oord)
13:00 – 16:00 Excursion  
  Bus ride with lunch (30 min)  
                                               Excursion Spanjaards Duin (60 min) Mennobart van Eerden (Rijkswaterstaat WVL) and Stéphanie IJff (Deltares)
  Bus ride (30 min)  
  Excursion Sand Motor (60 min) Kathelijne Wijnberg (University of Twente) and Sierd de Vries (TU Delft)
16:00 – 16:45 Drinks at Haagse Beek
Address: Machiel Vrijenhoeklaan 175
16:45 – 17:00 Bus ride to Den Haag Central Station  


Location: Provinciehuis Zuid Holland, Zuid Hollandplein 1, 2596 AW Den Haag

Registration: There are still some seats available during the morning program. The bus to the excusion is full, but if you have your own transport (or arrange to carpool with other participants), you can also attend the excursion. If you didn't register yet and would like to attend the theme day, please contact This email address is being protected from spambots. You need JavaScript enabled to view it. before Wednesday 15th of November.

Organization and contact: Organizing Committee: Bert van der Valk (chair, Deltares), Kathelijne Wijnberg (Universiteit Twente) and Sierd de Vries (TU Delft); Stéphanie IJff (Deltares)

The event is sponsored by the province of South-Holland and the Netherlands Centre for Coastal Research.


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