SR 4 over Tide Gate Culvert
Wahkiakum County, Washington · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- SR 4 over Tide Gate Culvert in Wahkiakum County, Washington, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the culvert, rated 8 (very good condition) on the 0-9 scale.
- It was built in 2015, making it 10 years old at the 2025 inventory.
- It carries about 2,084 vehicles a day (traffic count year 2023).
- Its listed owner is the state highway agency.
- It is one of 20 of the 37 inventoried bridges in Wahkiakum County rated good (54.1%); 1 (2.7%) 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 August 2023, on a 24-month routine inspection cycle.
- A good rating means every major component - deck, superstructure, substructure, or culvert - is rated 7 or higher on FHWA's 0-9 scale: no more than minor problems.
View this bridge on a map → (46.2236, -123.39267)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Culvert | 8 | 8 | Very good condition |
Bridge details
| Structure | Concrete culvert |
| Length | about 20 ft |
| Location | 29.4 E Jct SR 401 |
| NBI structure number | 0018610B0000000 |
| Condition class | Good |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | August 2023 |
| 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 Washington department of transportation.
Busiest bridges in Wahkiakum County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| SR 4 over Elochoman River | 1955 | 2,084 | Fair |
| SR 409 over Columbia R Puget Island | 1938 | 1,973 | Fair |
| SR 4 over Skamokawa Creek | 1939 | 1,573 | Fair |
| SR 4 over Deep River | 1990 | 1,509 | Good |
| SR 4 over Rangila Slough | 1990 | 1,509 | Good |
| SR 4 over W Fk Skamokawa CR | 1938 | 1,255 | Fair |
All bridges nearby: Wahkiakum County, WA bridge conditions · every bridge in Wahkiakum County · Washington bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.