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Floods of the Past, Design for the Future

Combining historical and geological insights with hydraulic numerical modelling to improve estimates of past Rhine river flood magnitudes


The goal of the project is to combine historical and geological insights with hydraulic numerical modelling to improve estimates of past Rhine river flood magnitudes. This leads to improved constraints on design discharges and validation of GRADE.


Design standards for flood protection in deltas require magnitude estimates of extreme (millennial) floods. The Dutch Delta Programme considers a design discharge of 18,000 m3/s an appropriate upper value the Rhine River at the German-Dutch border. Absence of a sufficiently long observational record of river discharge introduces considerable uncertainty in estimates of magnitude-frequency relations, which can only partly be solved by using statistical methods. Numerous historic flood marks along the German Rhine and sedimentary data of the youngest 2000 years contain valuable information on past extreme floods. In this interdisciplinary project we combine sedimentary and written archives from the delta with state-of-the-art reconstructions and numerical modelling approaches of past events to quantify magnitudes of large historic floods of the lower Rhine. The resulting method and computations allow evaluating the potential limits to design flood magnitudes and inundation cascades in the current situation in the Netherlands and adjacent Germany.


Anouk Bomers – Hydraulic modelling approaches to decrease uncertainty in flood frequency relations

Published papers

Van der Meulen, B., Bomers, A., Cohen, K.M., Middelkoop, H. (2021). Late Holocene flood magnitudes in the Lower Rhine river valley and upper delta resolved by a two-dimensional hydraulic modelling approach. Earth Surface Processes and Landforms. DOI: 10.1002/esp.5071.

Van der Meulen, B., Cohen, K.M., Pierik, H.J., Zinsmeister, J.J., Middelkoop, H. (2020). LiDAR-derived high-resolution palaeo-DEM construction workflow and application to the early medieval Lower Rhine valley and upper delta. Geomorphology. DOI: 10.1016/j.geomorph.2020.107370

Bomers, A., Van der Meulen. B., Schielen, R.M.J., Hulscher, S.J.M.H. (2019). Historic flood reconstruction with the use of an artificial neural network. Water Resources Research. 55(11), 9673-9688. DOI: 10.1029/2019WR025656

Bomers, A., Schielen, R.M.J., Hulscher, S.J.M.H. (2019). Decreasing uncertainty in flood frequency analyses by including historic flood events in an efficient bootstrap approach. Natural Hazards and Earth System Sciences. 19, 1895-1908. DOI: 10.5194/nhess-19-1895-2019

Bomers, A., Schielen, R.M.J., Hulscher, S.J.M.H. (2019). Consequences of dike breaches and overflow in a bifurcating river system. Natural Hazards. 97, 309-334. DOI: 10.1016/j.envsoft.2019.03.019

Bomers, A., Schielen, R.M.J., Hulscher, S.J.M.H. (2019). Application of a lower-fidelity surrogate hydraulic model for historic flood reconstruction. Environmental Modelling and Software. 117, 223-236. DOI: 10.1007/s11069-019-03643-y

Bomers, A., Schielen, R.M.J., Hulscher, S.J.M.H. (2019). The influence of grid shape and grid size on hydraulic river modelling performance. Environmental Fluid Mechanics. 19, 1273-1294. DOI: 10.1007/s10652-019-09670-4


View publications

Contact details

For information contact:
dr. Ralph Schielen (University of Twente)
dr. Kim Cohen (Utrecht University)

General info

Duration: 01/2015 - 12/2021

Research Positions: 2