Irr SD034 over Cheyenne Rv
Haakon County, South Dakota · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Irr SD034 over Cheyenne Rv in Haakon County, South Dakota, is rated in poor condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 4 (poor condition) on the 0-9 scale.
- It was built in 1962, making it 63 years old at the 2025 inventory.
- It carries about 567 vehicles a day (traffic count year 2024).
- Its listed owner is the state highway agency.
- It is one of 8 of the 69 inventoried bridges in Haakon County rated poor (11.6%); 8 (11.6%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- Its class is unchanged from 2024 (poor), but component ratings moved: superstructure 7 to 6.
- Its most recent inspection on record is dated February 2024, on a 24-month routine inspection cycle.
- It is coded scour critical (NBI item 113 = 3): scour critical: foundations unstable for the assessed or calculated scour.
- A poor rating means at least one major component - deck, superstructure, or substructure - is rated 4 or lower on FHWA's 0-9 scale. It does not by itself mean the bridge is unsafe; bridges judged unsafe are closed or load-restricted by their owners.
View this bridge on a map → (44.52891, -101.93007)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 5 | 5 | Fair condition |
| Superstructure | 7 | 6 | Satisfactory condition |
| Substructure | 4 | 4 | Poor condition |
Bridge details
| Structure | Continuous steel stringer or multi-beam girder |
| Length | about 1,204 ft |
| Location | Ziebach Co Line |
| NBI structure number | 000000028035151 |
| Condition class | Poor |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | February 2024 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 3: scour critical: foundations unstable for the assessed or calculated scour |
Source: FHWA National Bridge Inventory, 2025 data as reported by the South Dakota department of transportation.
Busiest bridges in Haakon County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US014 over Ck | 1955 | 978 | Fair |
| US014 over Ck | 1955 | 978 | Fair |
| US014 over North Fork Bad Rv | 1995 | 978 | Fair |
| SD073 over West Plum Ck | 1990 | 700 | Fair |
| SD073 over Grindstone Ck | 1954 | 700 | Fair |
| US014 over Ck | 1954 | 660 | Fair |
All bridges nearby: Haakon County, SD bridge conditions · every bridge in Haakon County · South Dakota bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.