Digues résistantes à la surverse dans les zones d'inondation contrôlées dans le bassin versant de l'Escaut maritime en Flandre (Belgique), et perspectives pour la France
Van Bockstal, P.; de Beukelaer-Dossche, M.; Nollet, S.; Peeters, P.; Vercruysse, J.B.; Nerincx, N. (2024).Digues résistantes à la surverse dans les zones d'inondation contrôlées dans le bassin versant de l'Escaut maritime en Flandre (Belgique), et perspectives pour la France, in: Colloque Digues 2024 - Systèmes et ouvrages de protection contre les inondations d'origines maritimes et fluviales. État des lieux, avancées, innovations et perspectives, Aix-en-Provence. pp. [1-10]. https://dx.doi.org/10.5281/zenodo.10600300 In: (2024). Colloque Digues 2024 - Systèmes et ouvrages de protection contre les inondations d'origines maritimes et fluviales. État des lieux, avancées, innovations et perspectives, Aix-en-Provence. [S.n.]: [s.l.]. , more |
| Available in | Authors | | Document type: Conference paper
|
| Keywords | Hydraulic structures > Dikes, shores and other flood defenses > Erosion protection
Belgium, Zeeschelde [Marine Regions]
| | Author keywords | dikes resisting to overflow, controlled flood areas, Scheldt, open stone asphalt, Sigma plan |
| Authors | | Top | - Van Bockstal, P., more
- de Beukelaer-Dossche, M., more
- Nollet, S.
| - Peeters, P., more
- Vercruysse, J.B., more
- Nerincx, N.
| |
| Abstract | The Sea Scheldt and its tributaries in Flanders are characterised by tides with amplitudes from 5 to 6 metres during calm weather, and up to 7,5 meters during storm tides. Due to floods in 1953 and 1976 the Sigma plan, approved in 1977, envisaged the elevation of the dikes and the creation of controlled flood areas to protect the endangered zones. Each controlled flood area contains 4 essential elements: 1) a new circular dike which confines the floodable area, 2) the flood area itself, 3) the original river dike, lowered and transformed into a dike that is resistant to overflow and 4) an engineering structure to empty the flood area.
In 2005, the Sigma plan was brought up to date and improved, adding as an additional goal to create tidal marshes in new flood areas, since these habitats had become rare in the Scheldt basin. The zone called “Polders of Kruibeke” is the largest flood area, having a surface of 692 ha and an overflow dike that is 6.6 km in length. Thanks to an inlet structure and the partial filling of the flood area twice a day on the rhythm of the tides, these polders create a huge environmental added value to the ecosystem of the Scheldt.
The overflow dikes that have been realised within the scope of the Sigma plan these last decades, all have a weak slope on the land side that is covered with open stone asphalt and a layer of loamy sand permitting to develop a herbal vegetation that resists to overflow rather well.
The overflow dikes of the Polders of Kruibeke and of other controlled flood areas have together endured hundreds of overflows, permitting to report on the functioning of those engineering structures in terms of hydraulic load and on the behaviour of the dikes and their facilities protecting against erosion. This article presents the concept and the construction of the resistant overflow dikes that have been constructed in the scope of the Sigma plan, and the experiences on the behaviour of these dikes during storm tides. It also proposes some application opportunities in
France. In particular the way how the resistance to overflow can contribute to conceiving flood protection systems from the socio-economical and technical point of view will be discussed. |
|
