In 2025, fire departments serving Walnut responded to 14 fire and hazmat incidents . Here's the full picture.
Grass fire lead by count. Building fires lead by dollars. Together the top five categories make up about 78% of all calls.
Mar peaks. May dips. Watch for the typical fall climb starting in October.
70 incidents 2021–2025. Peak year was 2023. $306K cumulative property loss.
| Year | Incidents | YoY | |
|---|---|---|---|
| 2021* | 3 | — | |
| 2022* | 7 | — | |
| 2023 | 29 | — | |
| 2024 | 17 | -41.4% | |
| 2025 | 14 | -17.6% |
* Well below Walnut's usual volume. That almost always means one or more departments didn't submit a full year to NFIRS, not that fires dropped, so no year-over-year change is shown for it.
For the 3 building fires Walnut departments responded to in 2025, here's how they were classified once investigators were finished.
NFIRS Area of Origin (AREA_ORIG) for the 27 building fires investigators classified across 2021–2025. The room or location where ignition occurred — kitchens, bedrooms, exterior, vehicle areas — tells you where to focus prevention.
| # | Area of origin | Count | Share | |
|---|---|---|---|---|
| 1 | Engine area, running gear, wheel area | 7 | 25.9% | |
| 2 | Cooking area, kitchen | 4 | 14.8% | |
| 3 | Wall surface: exterior | 4 | 14.8% | |
| 4 | Outside area, other | 4 | 14.8% | |
| 5 | Roof surface: exterior | 3 | 11.1% | |
| 6 | Undetermined | 2 | 7.4% | |
| 7 | Vehicle area, other | 1 | 3.7% | |
| 8 | Exterior, exposed surface | 1 | 3.7% | |
| 9 | Open area - outside; included are farmland, field | 1 | 3.7% |
NFIRS Heat Source (HEAT_SOURC) — the physical thing that started it. Spark or ember from operating equipment, an open flame, smoking materials, or hot embers from a fireplace are the leading culprits nationwide. Here's the Walnut mix.
| # | Heat source | Count | Share | |
|---|---|---|---|---|
| 1 | Arcing | 9 | 33.3% | |
| 2 | Radiated, conducted heat from operating equipment | 4 | 14.8% | |
| 3 | Undetermined | 4 | 14.8% | |
| 4 | Heat, spark from friction | 3 | 11.1% | |
| 5 | Heat source: other | 2 | 7.4% | |
| 6 | Heat from powered equipment, other | 1 | 3.7% | |
| 7 | Spark, ember or flame from operating equipment | 1 | 3.7% | |
| 8 | Hot or smoldering object, other | 1 | 3.7% | |
| 9 | Hot ember or ash | 1 | 3.7% | |
| 10 | Heat spread from another fire, other | 1 | 3.7% |
Per-capita rates let us compare apples to apples. Walnut sits above the national average for incidents per resident.
Top 25 wildfires (1992+) in the FPA-FOD ignitions database, scaled by acres. 9,640 acres burned in this 50-mile radius. Each dot is a fire — bigger dots burned more land.
| Year | Cause | Acres | Distance | |
|---|---|---|---|---|
| 2005 | Missing data/not specified/undetermined | 4,000 | 15.5 mi | |
| 2018 | Arson/incendiarism | 715 | 47.2 mi | |
| 2018 | Missing data/not specified/undetermined | 500 | 43.4 mi | |
| 2018 | Missing data/not specified/undetermined | 400 | 41.4 mi | |
| 2014 | Debris and open burning | 340 | 19.0 mi | |
| 2019 | Missing data/not specified/undetermined | 328 | 44.2 mi | |
| 2014 | Missing data/not specified/undetermined | 300 | 47.8 mi | |
| 2018 | Natural | 300 | 40.7 mi | |
| 2011 | Missing data/not specified/undetermined | 300 | 39.0 mi | |
| 2009 | Debris and open burning | 250 | 48.7 mi | |
| 2014 | Missing data/not specified/undetermined | 250 | 49.1 mi | |
| 2011 | Missing data/not specified/undetermined | 202 | 44.4 mi |
Top 1 ZIP codes by NFIRS incident count across 2021–2025. Each ZIP has its own fire profile — dive in for neighborhood-level context.
| # | ZIP | 5-yr incidents | |
|---|---|---|---|
| 1 | 51577 | 70 |
Six Iowa cities with population within ±25% of Walnut. Useful comparison targets — same state, similar size, different fire profile.
A 30-minute weekend can cut your home's exposure substantially. These four checklists are a good starting point.
Numbers reflect incidents reported by participating fire departments to the National Fire Incident Reporting System (NFIRS) Public Data Release for calendar year 2025. NFIRS is voluntary — about 23,000 of roughly 30,000 US fire departments report — so totals are a strong indicator, not a complete census. Per-capita comparisons use 2023 ACS population estimates. Wildland fire data complements NFIRS with NIFC and USFS perimeters. Active-fire counts come from a dated NIFC snapshot, not a live feed.