ABSTRACT
Many UK regions are flood-prone, with thousands of kilometres of flood defences having been installed to protect communities and infrastructure. Failure of flood defences usually results in huge socio-economic costs and occasionally human life. Since asset owners have limited resources to maintain infrastructure health, they often prioritise renewal and maintenance to assets that are nearing their ‘end of life’ based on risk analysis. This paper presents a methodology that was used to holistically evaluate the residual life of an existing 400m anchored sheet pile flood defence wall along a major river in UK. The approach included sensitivity analyses to understand risks more broadly and enabled further investigations or planned works to be informed, with awareness of how activities would impact on budget and programme constraints. Studies by previous consultants had concluded that the wall no longer had residual life. Sensitive factors which affect the anchor and sheet pile stability were identified, with the most sensitive factors being combined into models which represent the current and potential future conditions of the wall. A decision tree was then created, combining the critical sensitivity scenarios with the decision options which led to proportionate responses. The resultant benefits enabled the client to optimise resource deployment across their flood defence portfolio.
