Brief summary of research

In 2002, I became head of the group Water Engineering & Management, University of Twente. I hold the chair Marine and Fluvial Systems (MFS). Originally I was trained as a theoretical physicist (Utrecht University). During the PhD (partly at Physical Oceanography Utrecht University, partly Deltares) my focus was on physics of coastal seas. Nowadays, the research group I lead applies analytical and simulation techniques often supported by field or laboratory data to study the dynamics of rivers, coastal areas and offshore, from a civil engineering point of view. My research group gains knowledge of these water systems in order to predict the consequences of human interferences, including building with nature solutions as the sand engine and room for the river measures (flooding, sediment transport, etc.). This is done by analysis of field measurements, laboratory experiments, idealised modelling and complex modelling.

MFS devised a method for modelling human interferences in a morphodynamic setting. This opened perspectives for a new approach towards modelling large-scale sand mining in shallow seas. We have been studying the use of morphodynamical models in a societal context. This resulted in cooperations with social scientists, e.g on safety of coastal dunes, from physical as well as economical perspective.

I first tested earlier theoretical results against real-life observations and showed that bed patterns in the North Sea can be explained as free instabilities. Next, I initiated extended modelling of sandwave dynamics, so that we were the first in developing a fully nonlinear model of finite-amplitude sandwaves, taking a process-based simulation approach as well as a complex modelling approach.

In rivers we made idealized models for river dunes, as well as modelling the transition from dunes to upper stage plane bed, in which river dunes are washed out, which increasingly might occur in rivers due to climate change. I initiated working on modelling biogeomorphology in seas, estuaries, and rivers. We pioneered in modelling the effects of benthos in the marine sea bed and MFS is the first with a fully coupled biogeomorphological model for offshore sand waves and benthos.

Based on laboratory experiments we derived sediment transport formulations for rivers and coastal areas which are used all over the world.

I initiated writing (inter)national research proposals resulting in strong involvement of, and collaboration with, coastal and river managers, engineers and scientists from various disciplines, e.g. biologists, social scientists, mathematicians. I largely invested in creating a good research atmosphere in my group, stimulating internal cooperation, international research exchange, initiating several series of research talks, organising (inter)national conferences and involving MSc-students in our research. We have a highly diverse team (gender, continent, scientific specialisation).