ZIP 91789 recorded 54 fire and hazmat incidents in 2025, 249 across 2021–2025. Primary county: Los Angeles County, CA. FEMA NRI rates wildfire risk here as Very High.
249 incidents from 2021 through 2025 inside this ZIP.
| Year | Incidents | |
|---|---|---|
| 2021 | 46 | |
| 2022 | 41 | |
| 2023 | 50 | |
| 2024 | 58 | |
| 2025 | 54 |
Nov peaks. Feb dips. Aggregated across all 5 years inside this ZIP.
Top 5 NFIRS incident types for ZIP 91789 across 2021–2025.
| # | Incident type | Count | Share | |
|---|---|---|---|---|
| 1 | Outside rubbish fire, other | 30 | 12.0% | |
| 2 | Building fires | 20 | 8.0% | |
| 3 | Passenger vehicle fire | 18 | 7.2% | |
| 4 | Mobile property (vehicle) fire, other | 16 | 6.4% | |
| 5 | Outside rubbish, trash or waste fire | 15 | 6.0% |
For the 2 building fires reported here in 2025, here's how investigators classified ignition cause.
NFIRS Area of Origin for ZIP 91789 fires across 2021–2025.
| # | Area of origin | Count | Share | |
|---|---|---|---|---|
| 1 | Engine area, running gear, wheel area | 19 | 22.1% | |
| 2 | Vehicle area, other | 13 | 15.1% | |
| 3 | Undetermined | 9 | 10.5% | |
| 4 | Other | 8 | 9.3% | |
| 5 | Vehicle storage area; garage, carport | 7 | 8.1% | |
| 6 | Bedroom - < 5 persons; included are jail or prison | 3 | 3.5% | |
| 7 | Cooking area, kitchen | 3 | 3.5% | |
| 8 | Outside area, other | 3 | 3.5% | |
| 9 | All other areas | 21 | 24.4% |
NFIRS HEAT_SOURC code — the physical thing that started the fire.
| # | Heat source | Count | Share | |
|---|---|---|---|---|
| 1 | Heat source: other | 17 | 19.8% | |
| 2 | Heat from powered equipment, other | 17 | 19.8% | |
| 3 | Undetermined | 17 | 19.8% | |
| 4 | Arcing | 12 | 14.0% | |
| 5 | Hot or smoldering object, other | 5 | 5.8% | |
| 6 | Spark, ember or flame from operating equipment | 4 | 4.7% | |
| 7 | Heat from other open flame or smoking materials | 3 | 3.5% | |
| 8 | Radiated, conducted heat from operating equipment | 2 | 2.3% | |
| 9 | All other sources | 9 | 10.5% |
Largest single-incident losses in ZIP 91789 across 2021–2025. These 8 fires alone account for 343% of the ZIP's 2025 reported total.
| # | Property loss | Type | Year | Severity |
|---|---|---|---|---|
| 1 | $700,000 | Building fires | 2025 | Major |
| 2 | $500,000 | Building fires | 2023 | Major |
| 3 | $400,000 | Building fires | 2024 | Major |
| 4 | $400,000 | Building fires | 2024 | Major |
| 5 | $300,000 | Building fires | 2021 | Major |
| 6 | $250,000 | Building fires | 2022 | Major |
| 7 | $250,000 | Building fires | 2023 | Major |
| 8 | $250,000 | Fire in mobile home used as fixed residence | 2024 | Major |
Some ZIPs span multiple cities. Ranked by 5-yr NFIRS incidents inside ZIP 91789.
| # | City | 5-yr incidents | |
|---|---|---|---|
| 1 | Walnut | 130 | |
| 2 | Diamond Bar | 55 | |
| 3 | Pomona | 12 | |
| 4 | Rowland Heights | 10 | |
| 5 | West Covina | 1 |
The figures above are historical. For today's air quality, fire-weather warnings, and active fires, go to the official sources.
NFIRS reports each fire incident with a 5-digit address ZIP. We aggregate those rows directly to produce ZIP-level totals — 249 incidents in this ZIP across 2021–2025. Building-fire breakdowns (Area of Origin, Heat Source, ignition cause) only count fires investigators classified beyond the basic incident report. Because NFIRS reporting is voluntary, totals are a strong indicator rather than a complete census.