Lost River Rd over Lost River
Okanogan County, Washington · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Lost River Rd over Lost River in Okanogan County, Washington, is rated in poor condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 4 (poor condition) on the 0-9 scale.
- It was built in 1950, making it 75 years old at the 2025 inventory.
- It carries about 95 vehicles a day (traffic count year 2020).
- Its listed owner is the county highway agency.
- It is one of 12 of the 161 inventoried bridges in Okanogan County rated poor (7.5%); 12 (7.5%) are rated poor.
- A poor rating means at least one major component - deck, superstructure, or substructure - is rated 4 or lower on FHWA's 0-9 scale. It does not by itself mean the bridge is unsafe; bridges judged unsafe are closed or load-restricted by their owners.
View this bridge on a map → (48.6552, -120.50612)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 4 | Poor condition |
| Superstructure | 6 | Satisfactory condition |
| Substructure | 6 | Satisfactory condition |
Bridge details
| Structure | Continuous concrete stringer or multi-beam girder |
| Length | about 89 ft |
| Location | 6.3MI NW Mazama |
| NBI structure number | 080358000000000 |
| Condition class | Poor |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Washington department of transportation.
Busiest bridges in Okanogan County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 97 over Okanogan River | 1964 | 8,828 | Fair |
| US 97 over SR 155 | 1964 | 8,828 | Poor |
| US 97 over Gn Rr-county Road | 1964 | 7,453 | Good |
| SR 155 Spur over Okanogan River | 1923 | 5,987 | Fair |
| US 97 over Bonaparte CR | 1957 | 5,771 | Good |
| US 97 over Watson Draw | 1965 | 5,644 | Poor |
All bridges nearby: Okanogan County, WA bridge conditions · every bridge in Okanogan County · Washington bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.