2021 Marshall Fire

The purpose of this project is to collect and compile perishable data to support disaster recovery and mitigation from the December 2021 Boulder wildfire disaster. Additionally, this project demonstrates new technologies for rapid, field-based damage assessment, and will support development of decision support and planning tools for recovery. 

The main research questions that the project addresses are:

1. How do patterns of fire damage correlate with socio-economic indicators (i.e., housing type, tenure, affordability, insured/uninsured) and other factors associated with vulnerability?
2. What opportunities exist for wildfire risk mitigation through land use planning, site control, and design which can be documented and monitored through mapping, data visualization and spatial analytics? 
3. To what extent can longer term recovery planning and climate adaptation strategies emerge from the analysis of damage locations and clusters with opportunities for collective actions to reduce risk?

Site Tour 360 is an immersive media company specializing in virtual tours and 360 photography. Mike Vorce, president of Site Tour 360, collaborated with the NDPTC team to gather before and after imagery of the Marshall Fire.

How do patterns of fire damage correlate with socio-economic indicators and other factors associated with vulnerability?

Every community should prepare for and be ready to respond to hazardous events, including both natural and human caused disasters. The vulnerability of each community may be increased by the challenges it faces, including high rates of poverty, lack of access to a vehicle, and high density housing. These challenges may negatively impact that community’s ability to prepare for and respond to disasters.

The Social Vulnerability Index provides specific socially and spatially relevant information to help public health officials and local planners better prepare communities to respond to emergency events such as severe weather, wildfire, floods, disease outbreaks, or chemical exposure.

“It’s gonna be ten years before this town is back to normal again… And when you have 100 homes, or 2,300 homes or whatever, that all have to go through the permitting processes… And the permitting process was already nine months behind, or eight months behind, or whatever it was.” - resident affected by Marshall Fire

What opportunities exist for wildfire risk mitigation through land use planning, site control, and design which can be documented and monitored through mapping, data visualization and spatial analytics?

One way to assess fire risk is to look at the likelihood a building will be damaged if a fire breaks out nearby.

The map below shows contours of approximate conditional damage risk to buildings in and around the Marshall fire path. Many of the buildings that were affected by the fire had risk levels between 40 and 60 (on a scale of 1 to 100; Scott et al., 2020); few if any of the buildings had extremely low conditional risk levels.

“I realized that grass fires are as dangerous as forest fires...so that's a wake-up call.” - resident affected by Marshall Fire

Exposure levels also factor into fire risk evaluations. Exposure refers to a building's proximity to flammable vegetation and other buildings (Scott et al., 2020). According to the map below, the area in which the Marshall fire originated has a very high exposure score (0.9+ on a scale of 0 to 1), as does most of the fire's subsequent path. The fire eventually burned down entire neighborhoods after marching across a landscape that apparently had an abundance of fire fuel.

To what extent can longer term recovery planning and climate adaptation strategies emerge from the analysis of damage locations and clusters with opportunities for collective actions to reduce risk?

Many homes with low to moderate exposure levels burned to the ground. This might be attributable to the fact that they were in neighborhoods with high-exposure zones that directly abutted the path of the Marshall fire.

"One of my customers had two houses up across from the Costco, and they lost them both in 20 minutes. That’s how long it took to burn all the way down. You can’t stop that.” - resident affected by Marshall Fire

The heat map below shows how many of the homes that were damaged or destroyed on the eastern side of the fire were located in high-density housing unit areas (Scott et al., 2020). This suggests that after one or more high-exposure homes in dense neighborhoods caught on fire, the flames rapidly spread to other nearby units. This possibility means that the role of building density in determining exposure levels might need to be revisited.

Unfortunately, wildfires such as the Marshall Fire are likely to occur again. There is a need to improve capabilities and to use data to support recovery operations and longer term planning and community engagement. The following takeaways are meant to connect our team's research to actionable steps toward reducing wildfire risk for communities at risk.

Investing in safe, non-invasive damage assessment procedures can be beneficial during disaster recovery and within the context of COVID-19 exposure. The use of satellite and 360-degree Google Street View imagery, along with platforms like Zoom, allowed for our team to gather perishable damage assessment data with limited travel and exposure. Conducting interviews remotely with select individuals affected by the Marshall Fire, as well as working through community gatekeepers, allowed our research team to respectfully avoid overburdening emergency managers and community leaders actively engaged in disaster response and recovery. These methods might be employed by other damage assessment teams when risk of exposure for those conducting the assessment is high. There is a need to support and engage vulnerable, at-risk populations in the recovery process and address persistent equity concerns. Social vulnerability is defined in many different ways based on factors such as income, poverty, age, and neighborhood characteristics such as density, housing type and land cover to be integrated with the damage assessment which typically focuses on structural factors rather than social characteristics of neighborhoods. We need better plans for wildfire recovery and hazard mitigation. Building density and land use patterns play significant roles in shaping a community's risk. Local plannig efforts can focus on educating community members about their risk and exposure levels to help individuals and households take protective action.

Scott, J. H., Brough, A. M., Gilbertson-Day, J. W., Dillon, G. K., & Moran, C. (2020a). Wildfire Risk to Communities: Spatial datasets of landscape-wide wildfire risk components for the United States. Forest Service Research Data Archive. https://doi.org/10.2737/RDS-2020-001

Scott, J. H., Gilbertson-Day, J. W., Moran, C., Dillon, G. K., Short, K. C., & Volger, K. C. (2020b). Wildfire Risk to Communities: Methods for geospatial datasets for populated areas in the United States. Forest Service Research Data Archive. https://doi.org/10.2737/RDS-2020-0016

Anonymous Resident A. (2022). Marshall Fire Area Resident A Interview [In person].

Anonymous Resident B. (2022). Marshall Fire Area Resident B Interview [In person].

Anonymous Resident C. (2022). Marshall Fire Area Resident C Interview [In person].

Anonymous Resident D. (2022). Marshall Fire Area Resident D Interview [In person].

Anonymous Resident E. (2022). Marshall Fire Area Resident E Interview [In person].

Anonymous Resident F. (2022). Marshall Fire Area Resident F Interview [Audio recording].