EvacuAid: A Probabilistic Model to Determine the Expected Loss of Life for Different Mass Evacuation Strategies During Flood Threats

TLDR

Evacuation is a risk‑management strategy that can save lives but incurs time, money, and credibility costs, and its effectiveness depends on available time, citizen and authority response, and infrastructure capacity, yet existing flood‑risk literature largely focuses only on best‑case preventive evacuation. This study introduces EvacuAid, a probabilistic model that quantifies the expected loss of life for various evacuation strategies. EvacuAid is applied to a Dutch case study evaluating preventive and vertical evacuation under flood risk. The analysis shows that uncertainties in timing, citizen and authority responses, and infrastructure use significantly affect outcomes, underscoring the need for adaptive planning that incorporates both preventive and vertical evacuation within a risk‑management framework.

Abstract

Evacuation of people in case of a threat is a possible risk management strategy. Evacuation has the potential to save lives, but it can be costly with respect to time, money, and credibility. The consequences of an evacuation strategy depend on a combination of the time available, citizen response, authority response, and capacity of the infrastructure. The literature that discusses evacuations in case of flood risk management focuses, in most cases, only on a best‐case strategy as a preventive evacuation and excludes other possible strategies. This article introduces a probabilistic method, EvacuAid, to determine the benefits of different types of evacuation with regards to loss of life. The method is applied for a case study in the Netherlands for preventive and vertical evacuation due to flood risk. The results illustrate the impact of uncertainties in available time and actual conditions (e.g., the responses of citizens and authorities and the use of infrastructure). It is concluded that preparation for evacuation requires adaptive planning that takes preventive and vertical evacuation into account, based on a risk management approach.