Within the frame work of the realisation of the 'Actualised Sigmaplan', the opportunity to execute in situ breach tests following overflow is offered in the following years. Outcomes will serve to better understand the complex physical processes of embankment breaching for detailed model development and validation as well as for optimised dike design and maintenance strategies. In order to maximise outcomes of the full-scale field experiments international expertise is invited to join forces in the preparation of the testing program as well as to participate during the in situ breach test.