Burntfields® solutions: wildfire evacuation as a complex system - how to build resilient communities 

The word “evacuation” can provide a false sense of security as the impact of a wildfire is much more than vacating an area or one’s home. It is not a simple or singular event. Evacuations consist of multiple, interrelated factors and actors, making them complex in nature. Natural disasters are not linear. They change and evolve based on interactions of various moving parts. Viewing wildfires as linear oversimplifies them and can result in misleading conclusions.

Community and response management greatly impact evacuation timing during wildfires. Preparing communities for possibilities can minimize negative evacuation results. Small changes in advance of a wildfire event can have significant outcomes during and post-event. Emergency preparation can exploit the non-linear nature of wildfire evacuation, thus small preparations can have a much bigger impact.

Through understanding the complexities and a knowledge of potential risks, it is imperative to support and build resilience within these vulnerable communities in the face of wildfires.

Addressing an education gap on these complex systems, GHD’s subject matter expert Steve Gwynne alongside other international scholars collaborated to research and develop case studies. The case studies identify examples and insights into how system elements from design to governance interact to produce safe or unsafe outcomes. Now known as The Safer Complex Systems Case Study Collection with the Royal Academy of Engineering (UK), the team worked with other subject matter experts to examine the complexity of wildfire evacuations. They learned simulating real-life incidents can be beneficial to the safety and education of communities at risk of wildfire evacuations by exploring complexity and demonstrating consequences of different decisions on the outcomes produced.

Given the scale of such incidents, it is difficult to directly derive possible outcomes. Some numerical analysis is required to come up with evidence of performance. Evacuation plans prepare communities on how to safely exit the community in the event of a fire and when to do so. However, the dynamics of an event can slow or halt evacuation efforts. Conducting simulations provides understanding to how these dynamics unfold and put a number to the outcome, such as the time it takes for a population to evacuate an area. This allows comparison and assessment of options.

A wildfire evacuation has various factors that might influence the outcome. While a plan may be established, human response, weather conditions, land topography, infrastructure and the fire are highly coupled and directly impact one another affecting the complexity of the outcome – and the effectiveness of the plan in place. The combination of factors is unique to each wildfire event. To build a resilient community, the following factors need to be accounted for in the design and assessment of an evacuation plan:

• Road conditions. Road conditions affect the evacuating community reaching safety and the first responders from reaching the wildfire. Fallen forestry and infrastructure, car traffic and fire on the roads all impact response and evacuation time.
• Wildfires can expand and affect neighboring communities. This ultimately impacts all factors, including increasing the community demand of the road network, the need for emergency responders addressing the incident.
• Accounting for the organizations, individuals, businesses, communities and government agencies involved. Such large-scale events involve many affected parties. The coordination requires upfront planning and organization.
• Information sharing and gathering. Information may arrive from multiple sources, both informal (e.g. social media) and formal (e.g. emergency communication from emergency services). Multiple communication channels exist during wildfires, but they can overlap and confuse the community's understanding of the situation.
• Secondary fire incidents. Wildfire embers can catch onto surrounding areas, launching remote spot fires, making the evacuation process more challenging and susceptible to error.

With growing concern centering on the increase of wildfires it is imperative that we think toward real-life applications in community defense against wildfires. Creating a model example of real-life incidents that simulates conditions may uncover potentially vulnerable areas that were not thought of before. Models are simplifications of realistic wildfire events; therefore, it is important for planning and response agencies to identify and address potential evacuation approaches with the best outcome.

Understanding that wildfire evacuation is a complex system increases your communities’ ability to create safer conditions in the event of a disaster. In our Burntfields® Wildfire Risk Management Solution, preparedness includes research-based precautionary measures and actions to avoid and mitigate potential wildfire. Community hazard awareness and response training educate communities on wildfire safety and its complex systems.

Wildfire is not a linear event, which results in a complex reaction with various moving factors. Using experts who understand this complexity can ensure the proper application of evacuation models and integration with emergency response plans to greatly increase the ability to save lives and property during a wildfire.