Urban flood risks, water law and insurance: The intersection of emerging science, practice and authority

 By Professor Peter J Coombes

Published in Precedent issue 178 – September/October 2023, Journal of the Australian Lawyers Alliance

This article discusses the complex challenge of estimating flood risks in Australian urban areas and determining insurance contracts for recovery of storm and flood damages. Considerations include revised national guidelines for flood estimation (after 30 years); rapidly evolving science, methods and models; variable weather; a changing climate and a complex array of legislation and regulation. The application of emerging science is uncertain. Not even the definition of flood is settled in this context. We need to find a clear definition of flood risk that applies across multiple disciplines, and equitable processes for flood resilience.

We need a Pareto (balanced) analysis of costs and benefits to incorporate these trade-offs and achieve equity in finding the acceptable flood risk for particular locations. There is a need to prepare for rare flood events and to develop a reliable and defensible understanding of the potential impacts. However, there is also a requirement for normal activity between contested rare events that is more aligned with flood resilience approaches. We should not be sterilising high value land from human endeavour by an unduly conservative application of flood models, planning overlays and building assessments.

A copy of the journal paper is available here: Precedent 178 Peter J Coombes