139TH Street over Pero Creek
Walworth County, South Dakota · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- 139TH Street over Pero Creek in Walworth County, South Dakota, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the culvert, rated 7 (good condition) on the 0-9 scale.
- It was built in 1956, making it 69 years old at the 2025 inventory.
- It carries about 166 vehicles a day (traffic count year 2022).
- Its listed owner is the county highway agency.
- It is one of 11 of the 33 inventoried bridges in Walworth County rated good (33.3%); 1 (3.0%) are rated poor.
- A good rating means every major component - deck, superstructure, substructure, or culvert - is rated 7 or higher on FHWA's 0-9 scale: no more than minor problems.
View this bridge on a map → (45.37705, -100.17266)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Culvert | 7 | Good condition |
Bridge details
| Structure | Continuous concrete culvert |
| Length | about 20 ft |
| Location | 3N & 2.5W of Akaska |
| NBI structure number | 000000065145150 |
| Condition class | Good |
Source: FHWA National Bridge Inventory, 2025 data as reported by the South Dakota department of transportation.
Busiest bridges in Walworth County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US012 over Burlington Northern RR | 1969 | 2,111 | Good |
| US012 over Ck | 1969 | 2,111 | Good |
| Irr US012 over Missouri Rv (oahe Lk) | 1959 | 2,071 | Fair |
| Irr Ar US012 over Burlington Northern RR | 1957 | 2,071 | Fair |
| US012 over Blue Blanket Ck | 1964 | 1,963 | Fair |
| US012 over Ck | 1965 | 1,544 | Fair |
All bridges nearby: Walworth County, SD bridge conditions · every bridge in Walworth County · South Dakota bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.