The Insurance Institute for Business & Home Safety has released its report on the 2023 Lahaina Wildfire, which details the results of its post-disaster investigation into the deadliest U.S. wildfire in over a century. The report provides lessons learned and recommendations for protecting against future wildfires of that magnitude.

The document identified three main contributors to the rapid growth of the fire:

• Structure density: Flames from burning homes often extended over twenty feet, rapidly igniting homes at closer distances downwind. 
• Connective fuels: Connective fuels acted as pathways that brought fire to and enabled its spread through the built environment, including plants, secondary buildings and vehicles. 
• Building materials: Fire-resistant building materials offer higher resistance against thermal exposures compared to traditional materials, but their effectiveness was diminished in Lahaina due to intense heat from nearby burning buildings with limited structure separation.

On the community level, the report recommends taking the following actions in order to reduce the impact of these risks:

• Maintaining fuel breaks: Communities in wildfire-prone areas should develop and upkeep fuel breaks around developed areas to prevent grass fires from becoming conflagration events. 
• Expanding separation distances: Spacing buildings further apart can reduce the likelihood of building-to-building fire spread. Additionally, noncombustible privacy fencing materials can reduce the chances of wildfire spreading to other buildings.
• Promoting mitigation strategies: Communities should construct new buildings with wildfire resilience in mind.

Water and wastewater utilities should consider reading the executive summary of the report in order to better understand the environmental conditions that caused such an intense blaze and whether their organization’s facilities face a similar risk profile that needs to be mitigated. Read the executive summary here, or read a related news article at AP, or find out more about reducing natural hazard risk at the Insurance Institute for Business and Home Safety.

Amid increasing wildfire activity, water and wastewater utilities are encouraged to start preparing now for any potential impacts. Wildfires present a direct risk to property and water and wastewater infrastructure assets, in addition to potential degradation of the water supply, according to EPA. To help utilities enhance their resilience, EPA and CISA have created multiple free resources and online tools:

• EPA – Incident Action Checklist – Wildfire - Provides information on preparedness and response actions water utilities can take in a wildfire incident.
• EPA – Wildfire Conditions and Risk Map for Utilities - Provides information on current, past, and potential future wildfire conditions in the U.S. for utilities to assess the potential for wildfire near their facilities or within their watersheds.
• CISA – Wildfires - includes additional links to other fire preparedness resources.