3,701 Acres, Not 35,000: How Fire Pathways Turns Wildfire Risk Into Action

In Paradise, California, speed-based Fire Pathways™ modeling turned a 35,000-acre buffer concept that was too large to implement into a prioritized 3,701-acre treatment plan built around where mitigation can buy the most time.

Every fire-adapted community works within limits. Budget, staffing, and the acreage a crew can realistically treat in a season are all finite, and the town of Paradise, California, knows this better than most communities in the country.

The 2018 Camp Fire was the deadliest and most destructive wildfire in California's history. It killed 85 people and destroyed more than 18,800 structures across roughly 153,000 acres, most of it in a matter of hours. It showed what happens when a fast-moving, wind-driven fire reaches the built environment before residents and firefighting resources have time to respond. It is also the reason Paradise, Magalia, and Concow have spent the years since asking the question every fire-adapted community eventually has to answer: where should limited mitigation dollars actually go?

The First Answer Was Too Big to Build

The initial answer came from the Conservation Biology Institute, which identified Wildland Risk Reduction Buffers, wide bands of vegetation management placed between the urban edge and the surrounding wildlands. The buffers worked on paper. They also covered about 35,000 acres, a scope no community the size of Paradise has the crews, budget, or years required to treat.

That is the gap the Paradise Recreation and Park District asked XyloPlan to close. Not whether mitigation works, but where a constrained vegetation management program can do the most good. The result: a treatment footprint nearly 90% smaller than the original buffer concept, with the benefit measured not just in acres treated, but in hours gained. Here is how XyloPlan got there.

Modeling Where Fire Actually Moves, Not Where It Might Start

XyloPlan's Fire Pathways™ analysis starts from a different question than a static hazard map. Instead of scoring the probability that a fire starts in a given spot, it models where a fire will travel fastest once it does start, and where that speed collides with homes.

For Paradise, Magalia, and Concow, XyloPlan modeled two extreme fire weather scenarios from opposite directions: a dry, 24 mph northeast wind matching the actual Camp Fire conditions, and a dry, 18 mph southwest wind representing the other side of the study area. Fuel and terrain data came from the LANDFIRE dataset. Because LANDFIRE's fuel maps do not always capture golf courses, orchards, vineyards, and farmland as the non-burnable fuel breaks they actually are, XyloPlan corrected the dataset using a variety of open data sources, including OpenStreetMap.

Because the exact location of an ignition is unpredictable, and because probability tells a community very little when a single fire can be catastrophic regardless of the odds, the model does not try to guess where a fire starts. It draws an ignition line several kilometers upwind of the community and simulates fire spread along its entire length. The result is a map of Fire Pathways: the specific corridors where fuel, terrain, and wind align to carry fire toward homes fastest, and the entry points where those pathways first reach the built environment.

From 35,000 Acres to 3,701

Once the pathways were mapped, XyloPlan scored every potential treatment location on its ability to slow fire, not just its proximity to the wildland edge. The result is a set of Strategically Placed Local Area Treatments, or SPLATs, a method developed by Missoula Fire Sciences Laboratory researcher Mark Finney. Placed correctly, disconnected treatment patches interrupt a fire's forward spread even in the areas where fire is forced to flank around them.

The recommended plan for Paradise, Magalia, and Concow totals 3,701 acres: 2,190 on the northeast side and 1,511 on the southwest, a fraction of the original 35,000-acre buffer concept. Fully implemented, the northeast treatments are projected to add an average of 6.2 hours of fire arrival time for values at risk. The southwest treatments add an average of 2.3 hours, with the most effective locations delaying arrival by more than eight hours. Those additional hours can expand the window for resident egress and give firefighting resources more time to aggregate and respond before fire reaches values at risk.

Because no agency treats 3,701 acres in a single season, the plan divides the highest-priority pathways into three sequential tranches of roughly 730 acres each, ranked by treatment effectiveness. A district can fund and execute Tranche 1 first and still capture the largest share of the benefit, then build out from there as resources allow. (The plan also flags optional 200-meter grazing buffers around core treatment areas, which can boost effectiveness in open grass and brush and are not counted in the 3,701-acre total.)

Prioritized Beats Comprehensive

The lesson from Paradise is not that communities should do less. It is that limited mitigation resources should go first where they can change fire behavior the most.

That is the same question every fire agency, insurer, and community we work with is asking in some form: not "how much land is at risk," but "where would the next dollar of mitigation actually buy time." Paradise now has an answer measured in acres and hours, with a prioritized path from analysis to action.

To see the complete methodology, treatment maps, and tranche-by-tranche recommendations, read the full Fire Pathways™ Risk Assessment and Vegetation Treatment Plan for Paradise, Magalia, and Concow.

If your agency, district, or community is weighing a similar decision, reach out to XyloPlan today. We'll walk through what a Fire Pathways™ analysis could show for your area, and how a prioritized treatment plan, like the one built for Paradise Recreation and Park District, can make the most of the resources you already have.