System robustness analysis for flood and drought risk management

PhD research Marjolein Mens

Persons involved:

Marjolein Mens (candidate)
Eelco van Beek (promotor)
Frans Klijn (co-promotor)
Jeroen van der Sluijs (co-promotor)



In current risk-based decision making on floods and droughts, little attention is paid to low-probability/high-consequence risks. However, events with a low probability may cause such high consequences for society that they may be considered unacceptable. Instead of only trying to avoid extreme events from happening, by building high dikes or large reservoirs, we propose to also discuss whether consequences exceed an unacceptable level.

This research aims to enhance the applicability of the concept of system robustness, which is defined as the ability of a system to remain functioning under a range of disturbances. To that end, a framework is developed and tested to quantify ‘system robustness’. The proposed system robustness criteria should aid in choosing measures that reduce the risk in such a way that unacceptable consequences are avoided.

The main research question is: how to make the concept of robustness operational for flood and drought risk management?

The following subquestions are addressed:

1.Which definition of robustness is suitable for flood and drought risk systems?

2.Which criteria and indicators can be used to quantify robustness of flood and drought risk systems?

3.How can the robustness of flood and drought risk systems be increased?

4.What is the added value of robustness as guiding principle in flood and drought risk management?

The research is organised around 5 papers:

1.Conceptual framework for robustness analysis (published)

2.Application on a flood risk system (proof of concept) (under review)

3.Application on two flood risk systems to show added value in practice (under review)

4.Application on drought risk system in the US (under review)

5.Application on drought risk system in NL (draft)

List of publications related to this research


Mens, M. J. P., K. Gilroy, and D. Williams (under review), System robustness analysis applied to a water supply reservoir in the United States, Journal of Water Resources Planning and Management.


Mens, M. J. P., Klijn, F., Schielen, R. (under review) Enhancing flood risk system robustness in practice: insights from two river valleys. Journal of River Basin Management

Mens, M.J.P. and Klijn, F. (under review) The added value of system robustness analysis for flood risk management. Nat. Hazards Earth Syst. Sci.,


Klijn, F., Knoop, J. M., Ligtvoet, W., & Mens, M. J. P. (2012). In search of robust flood risk management alternatives for the Netherlands. Nat. Hazards Earth Syst. Sci., 12(5), 1469-1479.


Mens, M. J. P., Klijn, F., de Bruijn, K. M., & van Beek, E. (2011). The meaning of system robustness for flood risk management. Environmental Science & Policy, 14(8), 1121-1131.