Timeline modelling of flood evacuation operations

Abstract Analysing and modelling the time-dependent dynamics of complex flood evacuation operations by using a graphical timeline. The timeline is effective as a response planning tool and an effective means of communicating the complexity of the problem to others involved in planning, response or education. The modelling has guided the development of a strategic flood response plan for the Hawkesbury-Nepean valley west of Sydney, Australia. The modelling showed that flood evacuation capability as it stood in 1997, was seriously deficient in terms of road traffic carrying capacity. The flood evacuation timeline model was the central technical exhibit in the environmental assessment for a AUD$150 million to upgrade the regional road network. More recently, the methodology is being used to assess the flood evacuation capability for proposed large urban developments on floodplains. This paper explains the origins and development of the evacuation timeline concept and demonstrates its practical application to flood evacuation planning, flood risk assessment for urban development and in managing time critical flood response operations.