Wildfire Evacuation Research Articles

A household-level approach to staging wildfire evacuation warnings using trigger modeling

Wildfire evacuation trigger points are prominent geographic features (e.g., ridges, roads, and rivers) utilized in wildfire evacuation and suppression practices, such that when a fire crosses a feature, an evacuation is recommended for the communities or firefighters in the path of the fire. Recent studies of wildfire evacuation triggers have used Geographic Information Systems (GIS) and fire-spread modeling to calculate evacuation trigger buffers around a location or community that provide a specified amount of warning time. Wildfire evacuation trigger modeling has been applied in many scenarios including dynamic forecast weather conditions, community-level evacuation planning, pedestrian evacuation, and protecting firefighters. However, little research has been conducted on household-level trigger modeling. This work explores the potential uses of wildfire evacuation trigger modeling in issuing household-level staged evacuation warnings. The method consists of three steps: 1) calculating trigger buffers for each household; 2) modeling fire-spread to trigger the evacuation of all households; and 3) ranking households by their available (or lead) time, which enables emergency managers to develop a staged evacuation warning plan for these homes. A case study of Julian, California is used to test the method's potential and assess its advantages and disadvantages.

An exploration of residents’ intended wildfire evacuation responses in Mt. Lorne, Yukon, Canada

Wildfire evacuations disrupt people’s lives, create an additional hazard for emergency responders and residents, and are expensive to execute. Alternatives to evacuation are used in Australia and a few jurisdictions in the United States. Numerous studies have examined the “stay and defend” option during a wildfire in Australia, and evacuation alternatives have also been examined in the US. However, evacuation alternatives have not yet received scholarly attention in Canada. This study focused on the community of Mt. Lorne, Yukon, and explored residents’ perceptions of alternatives to evacuation due to wildfires, their evacuation intentions, and factors that influenced their intentions. Focus group participants planned to stay on their property despite a wildfire evacuation order because of the perceived safety of their property, and concerns about evacuating including leaving their property unprotected, losing harvested meat or other food stocks due to spoiling, and not knowing what to do with sled dog teams or livestock. However, some of these residents lacked the knowledge about how to stay on their property safely.

Wildfire evacuation and its alternatives: perspectives from four United States’ communities

Recent years have seen growing interest within the United States fire management community in exploring alternatives to the standard approach of evacuating entire populations that are threatened by a wildfire. There has been particular interest in what can be learned from the Australian approach, whereby residents choose whether or not to evacuate under the ‘prepare, stay and defend or leave early’ approach, also called Stay or Go. Given these developments, it is useful to understand what elements are taken into consideration by those who would be most affected by a new approach when they think through the pros and cons of mass evacuation v. an alternative strategy should a wildfire occur. This paper reports on findings from interviews in four communities in the United States where some alternative to mass evacuation during a wildfire was being considered. In each community, emergency responders and community members were asked for their perspective on the pros and cons of evacuation and the alternative being considered. The results show that opinions were mixed on whether evacuation or an alternative approach was more appropriate. Individuals who were primarily thinking of improving safety and reducing uncertainty for emergency responders tended to think mass evacuation was the best approach, whereas those who were primarily thinking of increasing safety and reducing uncertainty for homeowners were more likely to think that alternative responses were a valid option. These findings demonstrate the complicated nature of developing evacuation strategies that are beneficial to all parties involved.

Wildfire Evacuation Scenario in Colorado

In late 2010, the City of Colorado Springs and the Pikes Peak Area Council of Governments in Colorado completed a cooperative wildfire evacuation planning process. The process was supported by the simulation of wildfire evacuation scenarios with an adaptation of the Council of Governments’ four-step travel model. The adapted model was used to assess times to evacuate, identify choke points, and develop traffic control plans for identified at-risk neighborhoods. Evacuation simulations used a worst-case scenario in which the wildfire event took place during the p.m. peak traffic hour, and affected households were included in both background commuter traffic and neighborhood evacuation traffic. Link-based hourly volume-to-capacity ratios were used as a metric to estimate times to evacuate and to identify egress bottlenecks. Route closures, route restrictions, no-entry restrictions, and contraflow operations were evaluated as measures for inclusion in neighborhood-level traffic control plans. On Tuesday, June 26, 2012, the simulated worst case became reality. More than 34,000 persons were evacuated during the event, including 26,000 during the 6-h period between 15:30 and 21:30. Before the wildfire was fully contained, 18,247 acres had burned, 347 homes and other structures had been destroyed, and two people had died. That the no-notice, mandatory evacuation was as successful as it was can be attributed to extensive advance planning, the accuracy of modeled evacuation simulations, and the effectiveness of the final traffic control plans. This study examined how the model results were borne out by actual experience. Recommendations to improve no-notice evacuation planning from the perspective of lessons learned are presented.

Attitudes on wildfire evacuation: Exploring the intended evacuation behavior of residents living in two Southern California communities

Residents living within the Wildland-Urban Interface who fail to immediately evacuate during wildfire emergencies may not only increase the risk of injury or death to themselves but also to firefighters and rescuers tasked to protect them. In the coastal mountains of Santa Barbara County, CA, data on intended resident wildfire evacuation behavior does not exist. This research study used self-administered mail surveys to collect data on attitudes toward wildfire evacuation from more than 200 residents living within the High Fire Hazard Area of the Carpinteria Summerland Fire District (CA). Data derived from completed surveys indicate that although most residents intend to evacuate when given either voluntary or mandatory orders, 10 percent do not. A multivariate analysis performed on these residents indicates that men are less likely to evacuate than women, and long-term residents are less likely to evacuate than short-term residents. Further analysis of these residents indicates a wide variety of reasons for evacuation noncompliance, which are discussed in this study. Based on the results of these analyses, this research study provides recommendations to local public safety officials so they may better prepare for future wildfire evacuation events.

Wildfire evacuation and its alternatives in a post-Black Saturday landscape: Catchy slogans and cautionary tales

Prior to 2009 the United States and Australia were seeing increased interest, implementation and research support for alternatives to evacuation during wildfire – a broad class of strategies that would enable residents to remain in their homes or other designated safe areas during the pass of a flame front. Yet policy discussion of alternatives to evacuation in both countries shifted in the wake of Australia's 2009 Black Saturday Fires, which resulted in 173 deaths and burned approximately 430,000 ha. Soon after, the United States and Australia began implementing new approaches to public and property safety during wildfire events. The goal of this manuscript is to discuss key provisions of these emerging approaches to public safety during wildfire and evaluate their possible legacies. We do so by contrasting approaches in both countries with research insights on alternatives to evacuation during wildfire events. Insights are also paired with broader lessons from research on hazard, risk communication and wildfire. Our analysis provides insight on how emerging approaches could impact broader policy objectives for ‘creating fire-adapted communities’ and/or affect resident responsibility for personal wildfire protection. We suggest ways to influence these possible legacies through careful implementation and possible revision of emerging approaches to public safety during wildfire.

Mapping wildfire evacuation vulnerability in the western US: the limits of infrastructure

Residential development in fire-prone areas of the western United States is a growing concern. The steady addition of homes to this region places more people and property at risk each year. In many areas housing is increasing without commensurate improvements in the road network, particularly in regards to the number, capacity and arrangement of community exit roads. This results in steadily increasing minimum evacuation times, as each additional household contributes to potential evacuation travel-demand in a wildfire. The goal of this research is to perform a comprehensive geographic search of the western U.S. for communities in wildfire-prone areas that may represent difficult evacuations due to constrained egress. The problem is formulated as a spatial search for fire-prone communities with a high ratio of households-to-exits and solved using methods in spatial optimization and geographic information systems (GIS). The results reveal an initial inventory and ranking of the most difficult wildfire evacuations in the West. These communities share a unique vulnerability in that all residents may not be able to evacuate in scenarios with short warning time. For this reason they represent prime candidates for emergency planning, and monitoring their development is a growing need.

(A255) Medication Preparedness during Wildfire Evacuations

IntroductionDuring wildfires, many are evacuated with little time to collect personal items. Evacuees who depend on daily medication for ongoing medical conditions often arrive to evacuation shelters without medication and with little knowledge of what they require. This problem is reported for evacuees in the 2008 Orange County California (USA) Freeway Triangle Wildfires.MethodsData was obtained retrospectively from Orange County Health Care Agency records regarding people who required medication while housed in evacuation shelters. Descriptive data was analysed using SPSS 17 and STATA 11.01.Results40,000 persons were evacuated during the wildfires. Sixty of the evacuees aged from 6 to 82 years were without necessary medications. Of the sixty, there were 26 females and 34 males. People requiring medication would present to a public health nurse in the shelter whom would contact the Disaster Health Officer to arrange scripts for medication. Of the 60 people, 67% were unable to contact a primary physician and 75% were able to be issued a script for needed medication. The most common prescribed medication was albuterol for asthma and lung disease, then narcotic pain relief medication and next medication for cardiovascular / hypertension conditions.ConclusionsResults show that life sustaining medication was required by people housed in an evacuation shelter. These people may not have had time to retrieve necessary medication if they had to evacuate quickly or may not have had an adequate supply of medication at the time of evacuation. Thus far there has been very little published on this issue however, our results show there is a need for pre-planning on behalf of people living in wildfire prone areas who require daily medication and are at risk for sudden evacuation. Our findings also highlight the important role provided by health workers in evacuation shelters in providing assistance for medication purposes.

Wildfire evacuations in Canada 1980–2007

Evacuations represent an integral aspect of protecting public safety in locations where intense, fast-spreading forest fires co-occur with human populations. Most Canadian fire management agencies have as their primary objective the protection of people and property, and all fire management agencies in Canada recommend evacuations when public safety is in question. This study provides the first national assessment of wildfire-related evacuations in Canada and documents the loss of homes that coincided with evacuation events. The most striking finding is that despite the intensity and abundance of wildfire in Canada, wildfires have displaced a relatively small number of people. Between 1980 and 2007, the median number of evacuees and home losses per year in Canada were 3,590 and 2, respectively. Evacuees’ homes survived in 99.3% of cases. Patterns of evacuations and home losses reflected the distributions of forests, wildfire, and people across the Canadian landscape. Most evacuations occurred in boreal areas, which have relatively low population densities but among the highest percent annual area burned in Canada. Evacuations were less common in southern parts of the country, where most Canadians reside, but individual wildfires in these areas had significant impacts. Interactions between wildfire and people in Canada exhibited a unique regional pattern, and within the most densely populated regions of the country they can be considered ‘low-probability, high-consequence’ events. This Canadian context is fundamentally different from places such as California, where concentrations of fires and people overlap across large areas and therefore calls for a fundamentally different fire management response.

Wildfire Evacuation: Outrunning the Witch's Curse--One Animal Center's Experience

When the Witch Creek Fire began ravaging San Diego County, California, in October 2007 there was no way of knowing how far it would spread, how many homes it would destroy, how many families would be evacuated, or how many lives would be lost. There wasn't going to be any trail of bread crumbs to lead us out of the burning forest and safely back home. We weren't going to wake up and realize that it was a bad dream. This Witch was real and was devouring everything in her path. There might not be a home for us to return to.

Dynamic GIS Case Studies: Wildfire Evacuation and Volunteered Geographic Information

AbstractIncorporating the temporal element into traditional GIS is a challenge that has been researched for many years and has many proposed solutions. The implemented system “Extended Dynamic GIS” or EDGIS is based on the “geo‐atom” and Space Time Point (STP). EDGIS provides a platform for spatiotemporal data representation, storage, and query in order to address the need for a dynamic GIS to manage complex geographic data types. The system has the capability of executing spatiotemporal object interaction queries (OIQs) such as crossing and coincidence of field‐objects and object‐fields. In this article existing dynamic GIS analysis techniques are further improved and enhanced through exploration of more in‐depth case studies. Further examined here are applications to wildfire evacuation modeling and travel scenarios of urban environments with individuals providing volunteered geographic information (VGI). The EDGIS platform provides a means for interacting with a range of dynamic geographic phenomena. The areas of transportation, location based services (LBS), hazards, and geo‐sensor networks provide challenges intertwined with the above applications as well as additional challenges pertinent to the ongoing GIScience research topic of spatiotemporal GIS. Using EDGIS to explore the described case studies of wildfire evacuation as well as VGI provides the advancements described above and demonstrates implemented uses for dynamic GIS.

Emergency Planning in the Urban-Wildland Interface: Subdivision-Level Analysis of Wildfire Evacuations

This project was motivated by recent research that has advocated the need for a better understanding of and planning for evacuations of residential subdivisions under threat from wildfires. Prior work has suggested that the density of housing units and ineffective evacuation routing and egress may have contributed to fatalities in subdivisions in which residents were unable to evacuate when the need arose. To evaluate the effects of development density and street network layout, this study utilized simulation to represent and evaluate various evacuation scenarios at the neighborhood level under ranges of housing density and threat urgency. The results of this study illustrate the relationships between the traffic that can be accommodated by a roadway network; the location and number of egress points; and the time during which vehicles enter and exit the network. Most significantly, it showed how changes in traffic volume need to be accompanied by corresponding increases or decreases in time and/or egress capacity to move evacuees out of the threat zone. Similarly, changes in the network (i.e., adding and/or modifying the location of exits) were also shown to significantly decrease evacuation clearance times and increase the total exiting traffic.

Evacuation Behavior during Wildfires: Results of Three Case Studies

Abstract Evacuation of rural communities threatened by wildfires is occurring more often, particularly in the western United States. Residents, public safety officials, community leaders, and public land managers are facing the issues and problems of this new experience. We used semi-structured interviews to elicit the evacuation experience from the viewpoint of evacuees and public safety officials in three case studies of wildfire evacuations in the western United States during 2000 and 2002. (Our interviews were conducted only with Teller County residents and officials.) We identify and describe the stages of the evacuation process as experienced by evacuees, and the dynamics and dilemmas associated with each stage. We analyze these perceptions and dynamics using the sociological lenses of social construction of meaning and structuration. The results indicate that evacuees and public safety officials have different perceptions and concerns about the evacuation process. We derive lessons learned from these three cases for use in planning future wildfire evacuations.

Setting Wildfire Evacuation Trigger Points Using Fire Spread Modeling and GIS

Warning communities in the path of an advancing wildfire is a challenging problem. Decision makers need the most current information available to determine who should evacuate, when they should leave and what type of order to issue (e.g. mandatory, recommended, voluntary). This paper presents a new method for delimiting wildfire evacuation trigger points using fire spread modeling and GIS. Using data on wind, topography, and fuel in conjunction with estimated evacuation time, a trigger buffer can be computed for a community whereby an evacuation is recommended if a fire crosses the edge of the buffer. A case study is presented for the Corral Canyon section of the 1996 Calabasas Fire near Malibu, California, USA. The paper concludes with a discussion of the strengths and weaknesses of this approach.