ThatCarHitMe.com
An Injuria.ai Company
YEAR-OVER-YEAR CRASH REPORT · IOWA, IA · SEPTEMBER 2017
Purpose: Machine-readable JSON endpoint for AI agents, LLMs, researchers, and programmatic consumers. Returns all underlying crash data and AI-generated commentary without HTML.
Authentication: None required. Public endpoint.
GET: https://thatcarhitme.com/api/crash-data/reports/data/iowa/statewide/september-2017-report
Monthly Traffic Safety Analysis
4,630 CRASHES IN
IOWA, IA
SEPTEMBER 2017
In September 2017, there were 4,630 traffic crashes statewide, a 0.9% increase from the 4,589 crashes recorded in September 2016. While the total number of collisions remained relatively stable, the number of fatalities increased significantly. Year-over-year, total fatalities rose 45.2%, from 31 in September 2016 to 45 in September 2017.
4,630
▲ 0.9%was 4,589
Total Crash Events
45
▲ 45.2%was 31
Persons Killed
1,770
▲ 2.8%was 1,721
Persons Injured
40
▲ 33.3%was 30
Fatal Crash Events
Note: "Persons Killed" (45) counts individual fatalities across all crash events. "Fatal" in the severity table below (40) counts crash events where at least one fatality occurred. A single crash can result in multiple fatalities.
Source: Iowa Crash Data · ArcGIS Open Data · 2017-09-01 to 2017-09-30 · Aggregate counts from crash, person, and vehicle records
Trend Summary
Overall crash totals saw a slight increase of 0.9% from September 2016 to September 2017, rising from 4,589 to 4,630. However, the severity of these crashes worsened, with total injuries increasing by 2.8% from 1,721 to 1,770 and total fatalities climbing 45.2% from 31 to 45.
Vulnerable Road User Casualties
5
Pedestrians Killed
0
Cyclists Killed
40
Motorists Killed
0
Other Killed
32
Pedestrians Injured
63
Cyclists Injured
1,670
Motorists Injured
5
Other Injured
Source: Iowa Crash Data · ArcGIS Open Data · 2017-09-01 to 2017-09-30 · Mode classified from person records (driver/passenger → motorist; pedestrian; bicyclist → cyclist; in-line skater / unspecified → other)
When Crashes Happen
The temporal patterns of crashes remained largely consistent year-over-year. Friday was the day with the most crashes in both September 2016 (906 crashes) and September 2017 (960 crashes). The peak hour for collisions shifted slightly from 4 p.m. in the prior period (398 crashes) to 3 p.m. in the current period (396 crashes), with the afternoon commute hours consistently being the time of highest crash frequency.
Source: Iowa Crash Data · ArcGIS Open Data · 2017-09-01 to 2017-09-30 · Crash date field aggregated by weekday
Source: Iowa Crash Data · ArcGIS Open Data · 2017-09-01 to 2017-09-30 · Crash time field aggregated by hour (0-23)
Crash Severity Breakdown
The severity of crashes increased from the prior year. The fatal crash rate rose from 0.65% of all crashes in September 2016 to 0.86% in September 2017. The proportion of crashes resulting in serious injuries also grew, from 2.7% to 3.2% of all incidents. Consequently, the share of crashes with no reported injuries decreased from 69.1% to 67.5% year-over-year.
Severity is per crash event (most severe injury). 40 fatal crash events resulted in 45 persons killed.
Outcome by Severity (Crash Events)
Source: Iowa Crash Data · ArcGIS Open Data · 2017-09-01 to 2017-09-30 · KABCO injury classification scale
Severity Distribution (Crash Events)
Source: Iowa Crash Data · ArcGIS Open Data · 2017-09-01 to 2017-09-30 · Most severe injury per crash record
Top Contributing Factors
The leading contributing factors remained consistent, with "Followed too close" and "Animal" being the top two in both periods. The count of crashes attributed to following too closely decreased by 2.7% from 619 to 602, and animal-related crashes fell by 5.8% from 448 to 422. Notably, crashes involving "Improper or erratic lane changing" saw a 44.2% increase in count, from 77 to 111 incidents. Conversely, the count for crashes where a driver failed to yield from a stop sign decreased by 8.0%, from 275 to 253.
Officer-Reported Primary Contributing Cause
Source: Iowa Crash Data · ArcGIS Open Data · 2017-09-01 to 2017-09-30 · Officer-reported primary contributory cause per crash
Road & Environmental Conditions
In both periods, the vast majority of crashes occurred during daylight hours in clear weather on dry roads. The proportion of crashes under these ideal conditions increased in September 2017 compared to the prior year. Crashes on dry roads accounted for 84.9% of the total, up from 80.1%, while crashes in clear weather rose from 65.3% to 75.7% of the total. Conversely, the share of crashes in the rain decreased from 6.4% to 3.3%.
Weather
Source: Iowa Crash Data · ArcGIS Open Data · 2017-09-01 to 2017-09-30 · Weather condition at time of crash
Lighting
Source: Iowa Crash Data · ArcGIS Open Data · 2017-09-01 to 2017-09-30 · Lighting condition field
Road Surface
Source: Iowa Crash Data · ArcGIS Open Data · 2017-09-01 to 2017-09-30 · Road surface condition field
Vehicles & Demographics
The distribution of vehicle makes involved in crashes showed minimal change year-over-year. After combining abbreviated and full names, Chevrolet and Ford remained the top two makes in both periods, with nearly identical counts. The age demographics of individuals involved in collisions were also stable, with the 26-34 age group being the largest cohort in both September 2016 (1,368 persons) and September 2017 (1,326 persons).
Top Vehicle Makes (8,211 vehicles)
Source: Iowa Crash Data · ArcGIS Open Data · 2017-09-01 to 2017-09-30 · Vehicle unit records
1,047 persons with unknown or unrecorded age excluded from age chart.
Sex Distribution (5,409 persons with recorded sex)
Source: Iowa Crash Data · ArcGIS Open Data · 2017-09-01 to 2017-09-30 · Person-level records linked to crash events
Data Sources & Methodology
Primary Data Source
All crash data in this report is sourced from Iowa Crash Data, accessed programmatically via the ArcGIS 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 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: 2017-09-01 through 2017-09-30
- Report generated: September 9, 2026
Data Coverage
- Reporting period: 2017-09-01 through 2017-09-30 (30 days)
- Geographic scope: iowa, IA
- Total crash records analyzed: 4,630
- Total persons involved: 8,667
- Total vehicles involved: 8,211
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). "iowa, IA Crash Intelligence Report: September 2017." Published September 9, 2026. Reporting period: 2017-09-01 to 2017-09-30. Data source: Iowa Crash Data, ArcGIS Open Data. Available at: https://thatcarhitme.com/crash-data/iowa/statewide/september-2017-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
ThatCarHitMe.com · An Injuria.ai Company
ThatCarHitMe.com
An Injuria.ai Company
Crash Data Intelligence
Data: Iowa Crash Data · ArcGIS
Period: 2017-09-01 – 2017-09-30
Generated: September 9, 2026 · All rights reserved