Lake Flat, SD truck route planning & crash data
Plan safer truck routes in Lake Flat: commercial truck and garbage truck crashes in Lake Flat and Pennington County, dangerous roads, seasonality and route safety data for fleets. Patterns use Pennington County numbers.
Where fatal truck crashes happened
Risk scorecard
Key findings
Snapshot
Crashes by month
Garbage trucks vs all trucks
10 of 399 truck crashes since 2015.
Deadliest roads
No fatal large-truck crashes with a road name recorded here since 2015.
How Pennington County compares with South Dakota
Pennington County against South Dakota and the US, 2015–2025 (years with complete crash reporting). Per-resident rates make big and small places comparable.
Where Pennington County stands out
Full comparison
| Measure (2015–2025) | Pennington County | South Dakota | United States | vs state |
|---|---|---|---|---|
| Crashes per 100k residents / yr | 29.1 | 42.0 | 49.7 | 31% below the state |
| Deaths per 100 crashes | 3.0 | 5.2 | 3.4 | 42% below the state |
| Injuries per crash | 0.10 | 0.13 | 0.49 | 23% below the state |
| Garbage-truck share | 2.4% | 1.6% | 2.3% | 1.5× the state |
| On snow, slush or ice | 28.8% | 28.6% | 6.2% | same |
| Morning rush (6–10 am) | 21.0% | 22.2% | 23.7% | same |
| In rain, sleet or snow | 20.0% | 17.5% | 13.8% | 1.1× the state |
| Winter months (Nov–Mar) | 48.2% | 48.8% | 41.9% | same |
| After dark | 27.2% | 22.8% | 24.8% | 1.2× the state |
Pennington County has lower values than South Dakota for crashes per 100k residents / yr, deaths per 100 crashes and injuries per crash. It stands out for higher garbage-truck share, in rain, sleet or snow and after dark.
Pennington County at a glance: 1 in 41 garbage-truck share of crashes is 2.4%, against 1.6% for South Dakota.
Overview
Pennington County has recorded 399 truck crashes since 2015, with 38 people injured and 11 killed.
Across the years with complete reporting, that is roughly one truck crash every 11 days.
With 0 truck crashes reported in Lake Flat since 2015, this page uses Pennington County numbers for its patterns and comparisons.
When crashes happen
Truck crashes peak in January (11.8% of the year) and are lowest in February (5.3%).
Winter months (Nov–Mar) carry 48.2% of truck crashes, vs 48.8% for South Dakota.
The busiest hour is 2–3 pm, with 8.8% of truck crashes.
28.8% of truck crashes here happened on snow, slush or ice, against 28.6% across South Dakota.
Where crashes happen
No fatal crash involving a large truck has a recorded location within 10 miles of Lake Flat since 2015.
Garbage & waste trucks
10 crashes involved a garbage or refuse truck, a 2.5% share (South Dakota: 1.6%).
Route planning tips for Lake Flat fleets
- Plan January schedules with more margin; it is the worst month for truck crashes in Pennington County.
- Check your own stops for crash hotspots and low bridges with the free Route Planner.
About the data
This report uses the FMCSA crash file (reported crashes of trucks over 10,000 lb) and NHTSA FARS (fatal crashes). It reports the numbers without guessing at reasons.
Truck crashes by year: all trucks vs garbage trucks
Seasonality: when trucks crash in Pennington County
By hour of day
Most dangerous roads for trucks
No fatal crashes involving a large truck with a road name were recorded within 10 miles since 2015.
Roads named most in all truck crash reports
| Road | Truck crashes since 2015 (Pennington County) |
|---|---|
| I-90 | 194 |
| US-16 | 39 |
| Sd Hwy 44 | 26 |
| Sd Hwy 79 | 16 |
| Ave | 7 |
| Sd Hwy 445 | 7 |
| Us Hwy 16 B | 5 |
| Cambell St | 4 |
Lake Flat at a glance
| Population | 32 |
| Land area | 34.4 sq mi |
| Density | 1 per sq mi |
| Median household income (ZIP 57790) | $75,096 |
| Median home value (ZIP 57790) | $209,725 |
Waste facilities and haulers nearby
Historical data: truck crashes in Pennington 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 | 23 | — | 0.7 |
| 2000s | 24 | +2% | 1.0 |
| 2010s | 25 | +5% | 0.5 |
| 2020s | 42 | +67% | 1.0 |
Reported truck crashes averaged 23 a year in the 1990s and 42 a year in the 2020s. Reporting practices changed over time, so part of any change can come from reporting. NHTSA counts 1.0 fatal large-truck crashes a year in 2016–19 and 1.0 a year in 2020–24.
Nearby places
Questions fleets ask about Lake Flat
How many truck crashes happen in Lake Flat?
Pennington County has had 399 reported truck crashes since 2015, injuring 38 people and killing 11.
When do most truck crashes happen in Lake Flat?
The worst month is January: 11.8% of truck crashes in Pennington County happen then.
How many garbage truck accidents happen in Lake Flat?
Garbage trucks were involved in 10 reported crashes in Pennington County since 2015 (2.5% of truck crashes).
What is the truck crash rate in Lake Flat compared with South Dakota?
The yearly rate is 29.1 truck crashes per 100,000 residents in Pennington County, vs 42.0 for South Dakota.
How can I plan a safer truck route in Lake Flat?
The free Route Planner takes your stops and returns a route risk score, safer alternatives and low-bridge warnings.
2026 is a partial year. Updated October 2026.