SH 46 over Knowlton Creek
Camas County, Idaho · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- SH 46 over Knowlton Creek in Camas County, Idaho, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 5 (fair condition) on the 0-9 scale.
- It was built in 1955, making it 70 years old at the 2025 inventory.
- It carries about 630 vehicles a day (traffic count year 2023).
- Its listed owner is the state highway agency.
- It is one of 38 of the 62 inventoried bridges in Camas County rated fair (61.3%); 7 (11.3%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- Its class is unchanged from 2024 (fair), but component ratings moved: deck 5 to 7, superstructure 5 to 6.
- Its most recent inspection on record is dated August 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 fair rating means the lowest-rated major component scores 5 or 6 on FHWA's 0-9 scale: some deterioration or minor section loss, but the structure is sound. It is the middle class, not a warning.
View this bridge on a map → (43.33211, -114.71264)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 5 | 7 | Good condition |
| Superstructure | 5 | 6 | Satisfactory condition |
| Substructure | 5 | 5 | Fair condition |
Bridge details
| Structure | Concrete stringer or multi-beam girder |
| Length | about 40 ft |
| Location | 29.9 N. Gooding |
| NBI structure number | 000000000014405 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | August 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 Idaho department of transportation.
Busiest bridges in Camas County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 20 over Willow Creek | 2019 | 2,200 | Good |
| US 20 over No Name Creek | 1961 | 1,900 | Fair |
| US 20 over Hot Creek | 1961 | 1,900 | Fair |
| US 20 over Arnold Creek | 1961 | 1,900 | Fair |
| US 20 over Chimney Cr.;sheep CR. | 1961 | 1,900 | Fair |
| US 20 over Corral Creek | 1969 | 1,900 | Fair |
All bridges nearby: Camas County, ID bridge conditions · every bridge in Camas County · Idaho bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.