Making Levees Smart

A smart levee supplies information about the past, present and possible future status of the levee, for example in extreme conditions, allowing end-users to make sound decisions with the aim of delivering the required flood protection. In this approach, a smart levee is not the same thing as a levee fitted out with instruments: the intelligent element is not confined to the selective and thoughtful application of sensor technologies, it also implies understanding potential failure mechanisms, taking field conditions into account, and linking these factors to one another.

Monitoring supplies information about how a structure behaves. Relevance is not confined solely to the factor being monitored. For example, measuring water pressures in the subsurface below a dike for a number of weeks may result in the dike failing the statutory assessment. This has implications not only for the assessment itself, but also for levee management in general: inspections will be required sooner and more often when water levels are high.

The information obtained is also important for the design of any future upgrades. A pro-active approach will involve more and longer monitoring in order to establish a clear picture of how the levee responds. Conversely, if monitoring shows that this structure can withstand extreme loads without difficulty (such as extreme rainfall after a wet period), there can be a positive effect on management and assessment (with a possible reduction in inspection frequency).

Flood defences must be monitored on the basis of the specific information requirements of the relevant authority, management agency or expert, and on the basis of specific questions about how the defences behave. It is important to avoid monitoring for monitoring's sake.