Risk-based maintenance and inspection of riverine flood defence systems

The condition of flood defence revetments is influenced by many different degradation processes such as animal burrowing, rutting and growth of weeds. Many of these processes are shock-based rather than progressive continuous. As shocks can cause a drop in performance, this means that the condition of a revetment can suddenly decrease,...

Temporal evolution of backward erosion piping in small-scale experiments

Backward erosion piping (BEP) is a form of internal erosion which can lead to failure of levees and dams. Most research focused on the critical head difference at which piping failure occurs. Two aspects have received less attention, namely (1) the temporal evolution of piping and (2) the local hydraulic conditions in the pipe and at the pipe...

Optimal planning of flood defence system reinforcements using a greedy search algorithm

Climate change and deterioration require a continuous effort to reinforce flood defences and meet reliability requirements. To efficiently upgrade flood defence systems, insight in costs and benefits of measures at a system level is required throughout the process of planning and design. Due to the size of flood defence systems the number of...

A Bayesian hindcasting method of levee failures applied to the Breitenhagen slope failure

Hindcasting of past levee failures enhances insights in the performance and vulnerability of levees. The scarcity of field evidence makes identifying the cause(s) of failure difficult. Under these circumstances, multiple scenarios and model choices are possible to characterise and to model the failure. This paper shows how probabilistic...

Forensic Analysis of Levee Failures: The Breitenhagen Case

Forensic analysis of past failures is valuable to improve our understanding of levee behavior. In this article a new systematic approach of forensic analysis for levee failures is proposed and applied to the Breitenhagen levee breach that occurred along the river Saale in Germany in 2013. The purpose of this study is to identify the cause of the...

Incorporating Observations to Update the Piping Reliability Estimate of the Francis Levee

Piping failure of levees is one of the main contributors to flood risk. Piping occurs when the head difference over a levee results in uplift of the inland blanket, followed by backward erosion in the aquifer due to high local flow velocities. Whether piping occurs, highly depends on local geo-hydrological circumstances which are uncertain due...

Determination of Spatial Variability in d70 Grain Size Values Using High Density Site Measurements

Research to the failure mechanism piping (internal, backward erosion) in the Netherlands shows that the dikes require costly berms to meet the required safety standards. According to the Sellmeijer piping-formula, the d70 (70%-quantile of the grain size distribution by weight) is an important parameter in the resistance against piping. Therefore...