N-n Ramp over SR 515
King County, Washington · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- N-n Ramp over SR 515 in King County, Washington, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 8 (very good condition) on the 0-9 scale.
- It was built in 2017, making it 8 years old at the 2025 inventory.
- It carries about 27,969 vehicles a day (traffic count year 2019).
- Its listed owner is the state highway agency.
- It is one of 595 of the 1,252 inventoried bridges in King County rated good (47.5%); 50 (4.0%) 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 May 2024, 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 → (47.46873, -122.20829)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 8 | 8 | Very good condition |
| Superstructure | 8 | 8 | Very good condition |
| Substructure | 8 | 8 | Very good condition |
Bridge details
| Structure | Prestressed concrete stringer or multi-beam girder |
| Length | about 175 ft |
| Location | Jct SR 515 |
| NBI structure number | 0018811A0000000 |
| Condition class | Good |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | May 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 Washington department of transportation.
Busiest bridges in King County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I-90 EB over Sunset Creek | 2024 | 139,482 | Good |
| I-90 WB over Sunset Creek | 2024 | 139,482 | Good |
| N Queen Anne Dr over Ravine | 1935 | 125,000 | Fair |
| I-5 over Terrain | 1966 | 122,487 | Fair |
| SW Spokane St over Duwamish River W Waterwy | 1983 | 108,179 | Fair |
| I-5 over Terrain | 1966 | 106,282 | Fair |
All bridges nearby: King County, WA bridge conditions · every bridge in King County · Washington bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.