US 20 over C and NW Railroad
Natrona County, Wyoming · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- US 20 over C and NW Railroad in Natrona County, Wyoming, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 1977, making it 48 years old at the 2025 inventory.
- It carries about 11,584 vehicles a day (traffic count year 2024).
- Its listed owner is the state highway agency.
- It is one of 85 of the 135 inventoried bridges in Natrona County rated fair (63.0%); 5 (3.7%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- Its condition class and component ratings are unchanged from the 2024 inventory.
- 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 → (42.84669, -106.36721)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 7 | 7 | Good condition |
| Superstructure | 7 | 7 | Good condition |
| Substructure | 6 | 6 | Satisfactory condition |
Bridge details
| Structure | Continuous steel stringer or multi-beam girder |
| Length | about 270 ft |
| Location | Casper |
| NBI structure number | DDG |
| 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) | N: not over a waterway |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Wyoming department of transportation.
Busiest bridges in Natrona County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Wyo 220 over Garden Creek | 2001 | 26,351 | Fair |
| Wyo 220 over North Platte River | 1969 | 14,749 | Fair |
| Wyo 220 over BNSF Railway | 1969 | 14,641 | Fair |
| I-25 Sbl over North McKinley Street | 1958 | 12,618 | Fair |
| I-25 Nbl over North McKinley Street | 1958 | 12,577 | Fair |
| I-25 NBL and SBL over Walsh Drive | 2022 | 12,577 | Good |
All bridges nearby: Natrona County, WY bridge conditions · every bridge in Natrona County · Wyoming bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.