SR 109 over Unt to Boone Creek
Grays Harbor County, Washington · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- SR 109 over Unt to Boone Creek in Grays Harbor 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 2024, making it 1 years old at the 2025 inventory.
- It carries about 1,372 vehicles a day (traffic count year 2021).
- Its listed owner is the state highway agency.
- It is one of 188 of the 371 inventoried bridges in Grays Harbor County rated good (50.7%); 31 (8.4%) are rated poor.
- 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 → (47.15744, -124.18806)
Component ratings
| Component | Rating (2025) | FHWA scale meaning |
|---|---|---|
| Culvert | 8 | Very good condition |
Bridge details
| Structure | Concrete culvert |
| Length | about 27 ft |
| Location | 8.4 N Jct SR 15 |
| NBI structure number | 019567AB0000000 |
| Condition class | Good |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Washington department of transportation.
Busiest bridges in Grays Harbor County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 101 over Chehalis River | 1955 | 26,216 | Poor |
| US 12 over Camp Creek | 2024 | 23,177 | Good |
| US 12 over Wynoochee River | 1935 | 21,466 | Poor |
| US 12 over Unnamed Tributary | 2018 | 21,466 | Good |
| US 12 over Wishkah River | 1925 | 16,009 | Poor |
| US 12 / Heron St over Wishkah River | 1949 | 14,965 | Poor |
All bridges nearby: Grays Harbor County, WA bridge conditions · every bridge in Grays Harbor County · Washington bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.