Nfa 1179 (sa 1408) over Knob Creek
Clay County, Tennessee · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Nfa 1179 (sa 1408) over Knob Creek in Clay County, Tennessee, 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 1976, making it 49 years old at the 2025 inventory.
- It carries about 461 vehicles a day (traffic count year 2021).
- Its listed owner is the county highway agency.
- It is one of 51 of the 64 inventoried bridges in Clay County rated fair (79.7%); 3 (4.7%) 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: substructure 6 to 5.
- Its most recent inspection on record is dated April 2024, on a 24-month routine inspection cycle.
- 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 → (36.52405, -85.54137)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 7 | 7 | Good condition |
| Superstructure | 7 | 7 | Good condition |
| Substructure | 6 | 5 | Fair condition |
Bridge details
| Structure | Continuous prestressed concrete stringer or multi-beam girder |
| Length | about 185 ft |
| Location | 3 Mi S of SR-52 |
| NBI structure number | 14S42320001 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | April 2024 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 8: foundations stable, scour above the top of the footing |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Tennessee department of transportation.
Busiest bridges in Clay County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Fap 52 over Cumberland River | 1988 | 6,000 | Fair |
| Fap 52 over Overflow & Kyle St (A290 | 1987 | 6,000 | Fair |
| Fap 52 over Wet Weather Branch | 2013 | 3,949 | Good |
| Fap 52 over Wet Weather Branch | 2013 | 3,949 | Good |
| Fap 52 over SR-52 / Wet Mill CR. Rd. | 2013 | 3,949 | Fair |
| Fap 52 over SR-52 / Wet Mill CR. Rd. | 2013 | 3,949 | Fair |
All bridges nearby: Clay County, TN bridge conditions · every bridge in Clay County · Tennessee bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.