170 Street over Willow Ck
Codington County, South Dakota · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- 170 Street over Willow Ck in Codington County, South Dakota, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 7 (good condition) on the 0-9 scale.
- It was built in 1995, making it 30 years old at the 2025 inventory.
- It carries about 49 vehicles a day (traffic count year 2022).
- Its listed owner is the county highway agency.
- It is one of 15 of the 75 inventoried bridges in Codington County rated good (20.0%); 14 (18.7%) 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 → (44.91882, -97.00487)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 7 | Good condition |
| Superstructure | 7 | Good condition |
| Substructure | 7 | Good condition |
Bridge details
| Structure | Continuous concrete slab |
| Length | about 80 ft |
| Location | 4.9E 2N Watertown |
| NBI structure number | 000000015239160 |
| Condition class | Good |
Source: FHWA National Bridge Inventory, 2025 data as reported by the South Dakota department of transportation.
Busiest bridges in Codington County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US212 over Big Sioux Rv | 2019 | 14,592 | Good |
| US212 Ser Rd over Ck | 1970 | 12,968 | Fair |
| US212 over Willow Ck | 1970 | 10,862 | Fair |
| US081 over Big Sioux Rv | 1966 | 7,665 | Fair |
| W Kemp Avenue over Big Sioux River | 1935 | 5,053 | Fair |
| 14TH Ave. N Wtn. over Big Sioux Rv | 1974 | 4,970 | Poor |
All bridges nearby: Codington County, SD bridge conditions · every bridge in Codington County · South Dakota bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.