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2025 Annual Fire Report

Fires in San Lorenzo, California

In 2025, fire departments serving San Lorenzo responded to 144 fire and hazmat incidents — from cooking fires to gas leaks to a single $1.1M building blaze. Here's the full picture.

Updated Sep 27, 2026 Grade A Peak yr 2023 Alameda County 29,759 residents 0 reporting departments 680 5-yr
Total incidents
144
-5.3% vs 2024
Building fires
12
Residential 67% Other 33%
Property loss
$2.8M
$2.2M structure · $528K contents
Deaths & injuries
0 / 0
0 civilian deaths · 0 civ injuries · 0 firefighter injuries
01 The mix

What kinds of fires happen here?

Power line down lead by count. Building fires lead by dollars. Together the top five categories make up about 75% of all calls.

144
Total Incidents
Power line down 41 28.5%
Outside rubbish, trash or waste fire 34 23.6%
Trash or rubbish fire, contained 13 9.0%
Building fires 12 8.3%
Gas leak (natural gas or LPG) 8 5.6%
All other categories 36 25.0%
02 Seasonality

When do fires happen?

Feb peaks. Dec dips. Watch for the typical fall climb starting in October.

Jan 14
Feb 15
Mar 13
Apr 9
May 11
Jun 15
Jul 14
Aug 11
Sep 13
Oct 10
Nov 11
Dec 8
Fewer
More
2b Five-year trend

Year over year in San Lorenzo

680 incidents 2021–2025. Peak year was 2023. $4.2M cumulative property loss.

YearIncidentsYoY 
2021 123 —
2022 93 -24.4%
2023 168 +80.6%
2024 152 -9.5%
2025 144 -5.3%
03 Cause of ignition

What sparks building fires?

For the 12 building fires San Lorenzo departments responded to in 2025, here's how they were classified once investigators were finished.

Unintentional
50%
11
Cause undetermined
14%
3
Intentional / arson
0%
0
Equipment / heat source failure
23%
5
Under investigation
14%
3
Act of nature (lightning)
-1%
0
3b Where fires start

Where do fires start in San Lorenzo?

NFIRS Area of Origin (AREA_ORIG) for the 100 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 originCountShare 
1 Undetermined 20 20.0%
2 Cooking area, kitchen 13 13.0%
3 Engine area, running gear, wheel area 9 9.0%
4 Cargo/trunk area - all vehicles 5 5.0%
5 Equipment or service area, other 4 4.0%
6 Other 3 3.0%
7 Common room, den, family room, living room, lounge 3 3.0%
8 Bedroom - < 5 persons; included are jail or prison 3 3.0%
9 Storage area, other 3 3.0%
10 Vehicle storage area; garage, carport 3 3.0%
11 All other areas 34 34.0%
3c What ignited it

What actually ignited the fire?

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 San Lorenzo mix.

#Heat sourceCountShare 
1 Undetermined 45 45.0%
2 Heat from powered equipment, other 15 15.0%
3 Arcing 10 10.0%
4 Heat source: other 8 8.0%
5 Hot or smoldering object, other 4 4.0%
6 Spark, ember or flame from operating equipment 3 3.0%
7 Heat from other open flame or smoking materials 2 2.0%
8 Cigarette 2 2.0%
9 Radiated, conducted heat from operating equipment 1 1.0%
10 Molten, hot material 1 1.0%
11 All other sources 9 9.0%
04 The biggest fires

8 fires · $2.2M in losses

Largest single-incident property losses reported by San Lorenzo departments in 2025. These 8 fires alone account for 98% of the city's annual total.

# Property loss Type Severity Status
1 $1,100,000 Building fires Major Investigated
2 $800,000 Building fires Major Investigated
3 $50,000 Building fires Significant Investigated
4 $50,000 Passenger vehicle fire Significant Investigated
5 $50,000 Building fires Significant Investigated
6 $50,000 Building fires Significant Investigated
7 $50,000 Building fires Significant Investigated
8 $30,000 Building fires Significant Investigated
05 How San Lorenzo compares

San Lorenzo vs California vs the nation

Per-capita rates let us compare apples to apples. San Lorenzo sits below the national average for incidents per resident.

4.84
Incidents per 1,000 residents
San Lorenzo
4.84
CA avg
5.32
US avg
7.48
0.4
Building fires per 1,000 residents
San Lorenzo
0.4
CA avg
0.32
US avg
0.85
0
Civilian fire deaths per million
San Lorenzo
0
CA avg
2.9
US avg
5.9
5c Wildfires nearby

Wildfires within 50 mi of San Lorenzo

Top 25 wildfires (1992+) in the FPA-FOD ignitions database, scaled by acres. 630,462 acres burned in this 50-mile radius. Each dot is a fire — bigger dots burned more land.

50 mi radius
YearCauseAcresDistance 
2020 Missing data/not specified/undetermined 396,624 35.4 mi
2020 Missing data/not specified/undetermined 86,509 29.1 mi
2007 Recreation and ceremony 47,760 47.3 mi
1995 Recreation and ceremony 12,354 49.4 mi
2009 Missing data/not specified/undetermined 12,200 32.7 mi
2009 Missing data/not specified/undetermined 7,817 36.4 mi
2003 Equipment and vehicle use 6,804 42.0 mi
2005 Arson/incendiarism 6,744 28.4 mi
2003 Natural 5,018 42.1 mi
2020 Natural 4,929 45.3 mi
2016 Missing data/not specified/undetermined 4,474 42.5 mi
2020 Natural 4,279 47.2 mi
5d Top ZIPs

Where in San Lorenzo do fires concentrate?

Top 5 ZIP codes by NFIRS incident count across 2021–2025. Each ZIP has its own fire profile — dive in for neighborhood-level context.

#ZIP5-yr incidents 
1 94580 622
2 94578 38
3 94541 14
4 94577 3
5 94579 3
5e Peer cities

Cities similar to San Lorenzo

Six California cities with population within ±25% of San Lorenzo. Useful comparison targets — same state, similar size, different fire profile.

07 Stay prepared

Before the next Red Flag day.

A 30-minute weekend can cut your home's exposure substantially. These four checklists are a good starting point.

About this data

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.