ZIP 51535 (Griswold, IA) truck route planning & crash data
Plan safer truck routes around ZIP 51535: commercial truck and garbage truck crashes here and in Cass County, dangerous roads, seasonality and route safety data for fleets.
Where fatal truck crashes happened
Risk scorecard
Key findings
Snapshot
Crashes by month
Garbage trucks vs all trucks
0 of 388 truck crashes since 2015.
Deadliest roads
How Cass County compares with Iowa
Cass County against Iowa and the US, 2015–2025 (years with complete crash reporting). Per-resident rates make big and small places comparable.
Where Cass County stands out
Full comparison
| Measure (2015–2025) | Cass County | Iowa | United States | vs state |
|---|---|---|---|---|
| Crashes per 100k residents / yr | 245.0 | 68.1 | 49.7 | 3.6× the state |
| Deaths per 100 crashes | 6.0 | 3.5 | 3.4 | 1.7× the state |
| Injuries per crash | 0.39 | 0.41 | 0.49 | same |
| Garbage-truck share | 0.0% | 2.2% | 2.3% | 100% below the state |
| On snow, slush or ice | 25.4% | 18.7% | 6.2% | 1.4× the state |
| Morning rush (6–10 am) | 23.1% | 24.0% | 23.7% | same |
| In rain, sleet or snow | 21.1% | 15.1% | 13.8% | 1.4× the state |
| Winter months (Nov–Mar) | 49.3% | 45.4% | 41.9% | 1.1× the state |
| After dark | 41.0% | 23.1% | 24.8% | 1.8× the state |
Compared with Iowa, Cass County is lower on garbage-truck share. It runs above Iowa on crashes per 100k residents / yr, deaths per 100 crashes and on snow, slush or ice.
Cass County at a glance: 0 of truck crashes here involve garbage trucks: 0.0%, vs 2.2% in Iowa.
Overview
Cass County has recorded 388 truck crashes since 2015, with 178 people injured and 24 killed.
Across the years with complete reporting, that is roughly one truck crash every 11 days.
When crashes happen
Truck crashes peak in January (14.7% of the year) and are lowest in December (5.2%).
November through March accounts for 49.3% of truck crashes here, compared with 45.4% in Iowa.
By time of day, 9–10 am stands out with 6.4% of truck crashes.
25.4% of truck crashes here happened on snow, slush or ice, against 18.7% across Iowa.
Where crashes happen
Since 2015, fatal crashes with a large truck within 10 miles of ZIP 51535 happened on SR-92 (1) and US-6 (1); no road leads clearly.
Garbage & waste trucks
Since 2015, no garbage-truck crashes were reported for Cass County.
Route planning tips for ZIP 51535 fleets
- Review driver schedules for January, the month with the most truck crashes.
- Icy and snowy roads show up in 25.4% of truck crashes here, more than Iowa; schedule winter checks early.
- Use the free Route Planner to score your route and spot low bridges before drivers head out.
About the data
Crash counts come from the FMCSA crash file (police-reported crashes involving trucks over 10,000 lb); fatal-crash locations come from NHTSA FARS. Text on this page states only what these numbers show.
Truck crashes by year: all trucks vs garbage trucks
Seasonality: when trucks crash in Cass County
By hour of day
Most dangerous roads for trucks
| Road | Fatal truck crashes since 2015 (within 10 miles) |
|---|---|
| SR-92 | 1 |
| US-6 | 1 |
Roads named most in all truck crash reports
| Road | Truck crashes since 2015 (Cass County) |
|---|---|
| I-80 | 37 |
| Interstate 80/I 80 | 10 |
| I 80 Wb Mm59 | 5 |
| Olive St | 4 |
| I 80 W 59Mm | 4 |
| I 80 E 60Mm | 3 |
| Us 6/White Pole Rd | 3 |
| US-71 | 3 |
ZIP 51535 at a glance
| Population | 1,697 |
| Density | 5 per sq mi |
| Median household income | $76,371 |
| Median home value | $151,573 |
| Home ownership | 79% |
Waste facilities and haulers nearby
Historical data: truck crashes in Cass County since the 1990s
Combines the FMCSA crash file (all reported truck crashes, real coverage from about 1990) with NHTSA FARS (fatal crashes involving a large truck, 1982–2024).
| Decade | Truck crashes / yr | Change | Fatal crashes / yr (FARS) |
|---|---|---|---|
| 1990s | 16 | — | 0.5 |
| 2000s | 15 | -2% | 0.5 |
| 2010s | 26 | +69% | 1.0 |
| 2020s | 36 | +36% | 0.8 |
In the 1990s about 16 truck crashes a year were reported; in the 2020s, about 36. Reporting coverage also changed between these periods. NHTSA counts 1.2 fatal large-truck crashes a year in 2016–19 and 0.8 a year in 2020–24.
Nearby ZIP codes
Questions fleets ask about ZIP 51535
How many truck accidents are there in ZIP 51535?
Since 2015, 388 crashes involving commercial trucks were reported in Cass County (178 injured, 24 killed).
Which month has the most truck crashes in ZIP 51535?
January has the most truck crashes in Cass County, 14.7% of the yearly total.
How many garbage truck crashes are there in ZIP 51535?
Since 2015, Cass County has reported 0 garbage-truck crashes, or 0.0% of its truck crashes.
How does ZIP 51535 compare with Iowa for truck crashes?
Cass County records 245.0 truck crashes per 100,000 residents a year, against 68.1 across Iowa.
How can I plan a safer truck route in ZIP 51535?
Use the free Route Planner: enter your stops to get a risk score, safer alternatives and the low bridges on your route.
2026 is a partial year. Updated October 2026.