Monthly Traffic Safety Analysis

91 CRASHES IN
WALTHAM, MA
MAY 2025

All metrics benchmarked againstMay 2024

In May 2025, Waltham experienced a decrease in total crashes compared to May 2024, with 91 crashes reported this year versus 115 last year. This represents a 20.9% reduction in total crashes year-over-year. The most notable shift was the overall decline in crash incidents and associated injuries.

91

▼ -20.9%was 115

Total Crash Events

0

Persons Killed

23

▼ -17.9%was 28

Persons Injured

7

▼ -36.4%was 11

Hit-and-Run Crashes

Note: "Persons Killed" (0) counts individual fatalities across all crash events. "Fatal" in the severity table below (0) counts crash events where at least one fatality occurred. A single crash can result in multiple fatalities. 2 crashes with unreported severity are not shown in the severity breakdown.

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Aggregate counts from crash, person, and vehicle records

Trend Summary

The overall trend indicates a decrease in crash incidents year-over-year. Total crashes fell from 115 in May 2024 to 91 in May 2025, a reduction of 24 crashes. Similarly, total injuries decreased by 5, from 28 to 23.

7

Hit-and-Run Crashes — May 2025

▼ -36.4% vs prior (11)

Hit-and-run crashes decreased from 11 in May 2024 to 7 in May 2025, a reduction of 4 incidents. The hit-and-run rate also saw a decline, decreasing from 9.6% of total crashes to 7.7% year-over-year.

Vulnerable Road User Casualties

0

Pedestrians Killed

Prior: 0→0.0%

0

Cyclists Killed

Prior: 0→0.0%

0

Motorists Killed

Prior: 0→0.0%

3

Pedestrians Injured

Prior: 2↑50.0%

2

Cyclists Injured

Prior: 2→0.0%

18

Motorists Injured

Prior: 23↓-21.7%

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Mode classified from person records (driver/passenger → motorist; pedestrian; bicyclist → cyclist; in-line skater / unspecified → other)

When Crashes Happen

The temporal patterns of crashes shifted year-over-year. The peak day for crashes moved from Friday, with 26 incidents in May 2024, to Saturday, with 19 incidents in May 2025. The peak hour also changed, with 4 PM recording 13 crashes in May 2024, while 10 AM recorded 10 crashes in May 2025.

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Crash date field aggregated by weekday

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Crash time field aggregated by hour (0-23)

Crash Severity Breakdown

There were no fatal crashes in either May 2024 or May 2025. Total injuries decreased from 28 in May 2024 to 23 in May 2025. The number of possible injuries (C) decreased from 10 to 7, while minor injuries (B) remained constant at 13, increasing their share of total crashes from 11.3% to 14.3%.

Outcome by Severity (Crash Events)

Minor Injury13minor injury crashes14.3%
→0.0%prior 13
Possible Injury7possible injury crashes7.7%
↓-30.0%prior 10
No Injury69no injury crashes75.8%
↓-19.8%prior 86

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · KABCO injury classification scale

Severity Distribution (Crash Events)

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Most severe injury per crash record

Top Contributing Factors

Several contributing factors saw notable changes in crash counts. 'No improper driving' decreased by 10 crashes, from 22 in May 2024 to 12 in May 2025. 'Failed to yield right of way' also saw a reduction of 7 crashes, falling from 24 to 17. Conversely, 'Driving too fast for conditions' increased by 4 crashes, from 1 to 5, and 'Failure to keep in proper lane or running off road' increased by 3 crashes, from 2 to 5.

Officer-Reported Primary Contributing Cause

Failed to yield right of way17 (18.7%)↓-29.2%prior 24
Inattention15 (16.5%)↑7.1%prior 14
No improper driving12 (13.2%)↓-45.5%prior 22
Followed too closely10 (11%)↑25.0%prior 8
Other improper action6 (6.6%)
Driving too fast for conditions5 (5.5%)
Failure to keep in proper lane or running off road5 (5.5%)
Disregarded traffic signs, signals, road markings3 (3.3%)↓-57.1%prior 7
Made an improper turn3 (3.3%)↓-40.0%prior 5
Fatigued/asleep2 (2.2%)

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Officer-reported primary contributory cause per crash

Road & Environmental Conditions

Crashes occurring in 'Clear' weather conditions decreased significantly by 37, from 74 in May 2024 to 37 in May 2025. Similarly, crashes on 'Dry' road surfaces decreased by 28, from 94 to 66. In contrast, crashes on 'Wet' road surfaces increased by 4, from 20 to 24.

Weather

Clear37 (41.1%)
↓-50.0%prior 74
Cloudy22 (24.4%)
→0.0%prior 22
Rain9 (10.0%)
↓-10.0%prior 10
Clear/Clear8 (8.9%)
Rain/Cloudy7 (7.8%)
Cloudy/Rain3 (3.3%)
Cloudy/Sleet, hail (freezing rain or drizzle)2 (2.2%)
Cloudy/Cloudy1 (1.1%)
Rain/Severe crosswinds1 (1.1%)

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Weather condition at time of crash

Lighting

Daylight73 (80.2%)
↓-25.5%prior 98
Dark - lighted roadway9 (9.9%)
↓-10.0%prior 10
Dark - roadway not lighted4 (4.4%)
Dawn2 (2.2%)
Dusk2 (2.2%)
Other1 (1.1%)

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Lighting condition field

Road Surface

Dry66 (72.5%)
↓-29.8%prior 94
Wet24 (26.4%)
↑20.0%prior 20
Water (standing, moving)1 (1.1%)

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Road surface condition field

Vehicles & Demographics

The total number of vehicles involved in crashes decreased from 222 in May 2024 to 172 in May 2025. The involvement of FORD vehicles decreased by 17, from 32 to 15, and HONDA vehicles decreased by 7, from 42 to 35. Conversely, CHEVROLET vehicles involved increased by 8, from 7 to 15.

Top Vehicle Makes (172 vehicles)

1
HONDA35 (20.3%)
↓-16.7%prior 42
2
TOYOTA27 (15.7%)
↓-18.2%prior 33
3
CHEVROLET15 (8.7%)
↑114.3%prior 7
4
FORD15 (8.7%)
↓-53.1%prior 32
5
JEEP10 (5.8%)
↑25.0%prior 8
6
NISSAN10 (5.8%)
↓-16.7%prior 12
7
MAZDA6 (3.5%)
→0.0%prior 6
8
MERCEDES-BENZ5 (2.9%)
↓-37.5%prior 8
9
GMC5 (2.9%)
10
BMW4 (2.3%)

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Vehicle unit records

15 persons with unknown or unrecorded age excluded from age chart.

Sex Distribution (202 persons with recorded sex)

Male127 (62.9%)
↓-12.4%prior 145
Female75 (37.1%)
↓-12.8%prior 86

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Person-level records linked to crash events

Speed Limit Zones

Crashes in 25 mph zones remained relatively stable, decreasing slightly from 48 in May 2024 to 47 in May 2025. Crashes in 30 mph zones saw a notable decrease, falling from 29 to 15. Conversely, crashes in 65 mph zones increased from 2 to 5.

Source: Massachusetts Crash Data (MassDOT CDV) · Arcgis_yearly Open Data · 2025-05-01 to 2025-05-31 · Posted speed limit at crash location

Data Sources & Methodology

Primary Data Source

All crash data in this report is sourced from Massachusetts Crash Data (MassDOT CDV), accessed programmatically via the Arcgis_yearly Open Data API (SODA). This dataset contains official police-reported motor vehicle traffic crash records maintained by the reporting jurisdiction's law enforcement agency. Records are published to the open data portal by the municipality and are subject to the portal's terms of use.

Data Retrieval

  • Access method: Arcgis_yearly Open Data API (SoQL queries)
  • Data format: Structured JSON via REST API
  • Record types queried: Crash events, person records, and vehicle unit records
  • Date filter applied: 2025-05-01 through 2025-05-31
  • Report generated: June 21, 2026

Data Coverage

  • Reporting period: 2025-05-01 through 2025-05-31 (31 days)
  • Geographic scope: WALTHAM, MA
  • Total crash records analyzed: 91
  • Total persons involved: 216
  • Total vehicles involved: 172

Analytical Methodology

  • Severity classification: Uses the KABCO injury scale (K=Fatal, A=Incapacitating injury, B=Non-incapacitating injury, C=Possible injury, O=No injury/property damage only), the standard classification in U.S. Model Minimum Uniform Crash Criteria (MMUCC). Severity is assigned per crash event based on the most severe injury in that crash. A single fatal crash (K) may involve multiple fatalities; therefore the "Persons Killed" count in the headline KPIs may differ from the "Fatal" crash count in the severity breakdown.
  • Contributing factors: Reflect the officer-determined primary contributory cause recorded at the time of the crash report. These are preliminary determinations and may not reflect final investigation findings.
  • Hit-and-run classification: Based on the hit-and-run indicator field in the official crash report, as determined by the responding officer at the scene.
  • Temporal analysis: Day-of-week and hour-of-day distributions are computed from the crash date/time timestamp in each record.
  • Demographics: Age and sex distributions are drawn from person-level records linked to each crash event. A single crash may involve multiple persons.
  • Vehicle data: Make information is drawn from vehicle unit records linked to each crash event.
  • AI commentary: Narrative sections are generated by Google Gemini (large language model) based on the structured data. Commentary is descriptive, not predictive, and should not be interpreted as expert opinion.

Limitations & Disclaimers

  • Only crashes reported to and documented by law enforcement are included. Minor incidents, unreported crashes, and near-misses are not captured in this dataset.
  • Data reflects conditions at the time of the initial police report and may be subject to subsequent corrections, reclassifications, or supplements by the reporting agency.
  • Open data portal records may experience a publication lag - recently occurring crashes may not yet appear in the dataset at the time of report generation.
  • AI-generated commentary is produced by a large language model and is intended to highlight patterns in the data. It does not constitute legal, medical, or professional analysis.
  • Percentages are calculated from reported data and are subject to rounding.

Non-Affiliation Disclosure

This report is produced independently by ThatCarHitMe.com (Injuria.ai). It is not affiliated with, endorsed by, or produced in partnership with any law enforcement agency, municipal government, state department of transportation, or the National Highway Traffic Safety Administration (NHTSA). Data is sourced from publicly available government open data portals.

Data License

The underlying crash data is provided under the municipality's Open Data Terms of Use and is made available to the public for unrestricted use. This analysis and report is © 2026 Injuria.ai and may be cited with attribution using the suggested citation below.

Corrections & Feedback

If you believe any data in this report is inaccurate or have questions about our methodology, please contact: data@injuria.ai. We are committed to accuracy and will issue corrections promptly.

Suggested Citation

ThatCarHitMe.com (Injuria.ai). "WALTHAM, MA Crash Intelligence Report: May 2025." Published June 21, 2026. Reporting period: 2025-05-01 to 2025-05-31. Data source: Massachusetts Crash Data (MassDOT CDV), Arcgis_yearly Open Data. Available at: https://thatcarhitme.com/crash-data/massachusetts/waltham/may-2025-report

About the Publisher

ThatCarHitMe.com is a crash data intelligence platform developed by Injuria.ai, a legal technology company specializing in traffic safety analytics. We aggregate and analyze publicly available government crash data to produce structured intelligence reports for communities, researchers, journalists, and legal professionals. Our reports combine programmatic data retrieval from official open data portals with AI-assisted narrative analysis.

Questions about this report's data or methodology: data@injuria.ai

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Waltham, MA Crash Report — May 2025 | ThatCarHitMe.com