With over one-third of the country lying below sea level and as the delta of major rivers such as the Rhine and Meuse, the Netherlands has had a long relationship with flood risk.
The Dutch water boards are the institutions responsible for keeping the country dry and safe, ever since the foundation of the first water board in 1248, over 750 years ago. An elaborate network of over 13,000 km of dikes and levees protect the country.Our services consist of dike safety studies, conducted from a hydrological and geophysical perspective. In addition, we provide institutional and management consultancy. Well placed in the middle of the Dutch water sector, through partnerships NECTÆRRA can bring to bear extensive experience in other fields of expertise, such as geotechnics and scientific R&D.
Read about several projects below:
dike failure pilotA unique study to collapse a dike and evaluate failure behaviour, soil strength and modelling predictions
A study started in 2014 to collapse a dike/levee along a waterway in the Netherlands allowing evaluation of failure behaviour, soil strength and the dike stability and failure modelling predictions. The Leendert de Boerspolder was a small island near Leiden City, which allowed to be inundated to compensate surface water losses, improve general water quantity and add ecological and recreational value. This was done by artificially stressing the dike over a short length until its failure. This occured at the end of 2015. NECTÆRRA acted as technical manager of the project for the water board. The field data is currently being used for extensive additional research by the Technical Universty Delft and several PhD. students. Goals are to test the quality of failure prediction models and the dike strength and behaviour as it collapses. Also, the study has provided new insights into monitoring techniques and the process of inundation. Data was fed real-time into the Dike Data Service Center (DDSC). The pilot was conducted in a broad collaboration between water boards, knowledge centres and private companies.
Dike and levee assessmentsTechnical assessments of dikes and levees for water defense
Broad technical and management services for the water board of Rijnland in the field of water protection, which includes assessing vulnerable areas, dike/levee composition and necessary measures to improve and maintain dike integrity and water protection functions. Activities include broader technical managment and oversight of specialized engineering firms for strength assessments and the design and implementation of dike improvement works. This water boards covers the populous area between Amsterdam and The Hague, and has over 1200 km of dikes and levees offering protection from the North Sea and an array of interconnected lakes and waterways.
Satellite information and hydrogeology in dike inspectionSatellite RS and hydrogeology in dike drought inspections
In the west and north of the Netherlands many dikes and levees are especially susceptible to drought as many dikes consist partly of peat. In practice, during periods of drought extensive field inspections are undertaken to assess possible damage caused by this drying. This process is laborious and expensive, with often uncertain effects while assessing only visual signs of dryness at the dikes surface. As satellite information has become more available and with higher temporal and spatial resolution, a study is underway to assess the use of satellite remote sensing for inspection and monitoring of dikes. This study is being supported by a scientific grant of the Dutch government. In addition to the assessment of satellite potential – which is conducted with various specialized remote sensing organisations – it involves the evaluation and where required reformulation of the inspection process in a broad sense. This also involves more detailed geological and hydrological evaluations, classifications and modelling. Feasibility and subsequent implementation results are expected early 2017.