Hwy 603 over Chehalis River
Lewis County, Washington · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Hwy 603 over Chehalis River in Lewis County, Washington, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 1991, making it 34 years old at the 2025 inventory.
- It carries about 1,697 vehicles a day (traffic count year 2022).
- Its listed owner is the county highway agency.
- It is one of 194 of the 420 inventoried bridges in Lewis County rated fair (46.2%); 17 (4.0%) are rated poor.
- 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 → (46.64167, -123.01333)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Deck | 6 | Satisfactory condition |
| Superstructure | 8 | Very good condition |
| Substructure | 8 | Very good condition |
Bridge details
| Structure | Continuous prestressed concrete stringer or multi-beam girder |
| Length | about 376 ft |
| Location | 0.15 S.E. SR 6 |
| NBI structure number | 085987000000000 |
| Condition class | Fair |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Washington department of transportation.
Busiest bridges in Lewis County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I-5 over Salzer Creek | 1951 | 38,131 | Fair |
| I-5 over Cw Ry | 1953 | 36,296 | Fair |
| I-5 over Np Ry & Dillenbaugh CR | 1954 | 36,296 | Fair |
| I-5 over RR & Reynolds Rd. | 2013 | 34,754 | Good |
| I-5 over Blakeslee Jct RR | 2015 | 34,754 | Good |
| I-5 over Dillenbaugh Creek | 1952 | 32,739 | Good |
All bridges nearby: Lewis County, WA bridge conditions · every bridge in Lewis County · Washington bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.