Old Valdez Trail over Twenty-three Mile Slough
Fairbanks North Star Borough, Alaska · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Old Valdez Trail over Twenty-three Mile Slough in Fairbanks North Star Borough, Alaska, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the superstructure, rated 5 (fair condition) on the 0-9 scale.
- It was built in 2004, making it 21 years old at the 2025 inventory.
- It carries about 10 vehicles a day (traffic count year 2018).
- Its listed owner is the county highway agency.
- It is one of 51 of the 112 inventoried bridges in Fairbanks North Star Borough rated fair (45.5%); 6 (5.4%) 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 6 to 7.
- Its most recent inspection on record is dated August 2024, on a 24-month routine inspection cycle.
- It has fracture-critical members (NBI item 92A): steel tension members without a redundant load path, which get their own scheduled inspections.
- 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 → (64.65618, -147.17145)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 7 | Good condition |
| Superstructure | 5 | 5 | Fair condition |
| Substructure | 6 | 6 | Satisfactory condition |
Bridge details
| Structure | Steel multiple box beam |
| Length | about 44 ft |
| Location | Mile Point 0.9 |
| NBI structure number | 2294 |
| 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) | 8: foundations stable, scour above the top of the footing |
| Fracture critical (item 92A) | Yes |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Alaska department of transportation.
Busiest bridges in Fairbanks North Star Borough
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Steese Highway over Chena River (steese Hwy) | 1977 | 23,300 | Fair |
| Johansen Expresswy over Geist Road Overhead | 1989 | 18,300 | Fair |
| Johansen Expresswy over Noyes Slough (geist Rd) | 1993 | 18,000 | Fair |
| Johansen Expresswy over Peger/geist Overcrossing | 1993 | 18,000 | Fair |
| Richardson Highway over Badger Loop U.c. | 2002 | 16,900 | Good |
| Richardson Highway over Rich Hwy Oh Mp 359 SB | 2024 | 16,900 | Good |
All bridges nearby: Fairbanks North Star Borough, AK bridge conditions · every bridge in Fairbanks North Star Borough · Alaska bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.