Interstate 81 Nbl over Rte 686/MULBERRY Ln
Smyth County, Virginia · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Interstate 81 Nbl over Rte 686/MULBERRY Ln in Smyth County, Virginia, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 7 (good condition) on the 0-9 scale.
- It was built in 2020, making it 5 years old at the 2025 inventory.
- It carries about 15,800 vehicles a day (traffic count year 2022).
- Its listed owner is the state highway agency.
- It is one of 31 of the 189 inventoried bridges in Smyth County rated good (16.4%); 7 (3.7%) 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 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 → (36.86452, -81.42299)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 7 | 7 | Good condition |
| Superstructure | 7 | 7 | Good condition |
| Substructure | 7 | 7 | Good condition |
Bridge details
| Structure | Steel stringer or multi-beam girder |
| Length | about 163 ft |
| Location | 3.68 to R11 & 3.37 to 683 |
| NBI structure number | 000000000030971 |
| Condition class | Good |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | August 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 Virginia department of transportation.
Busiest bridges in Smyth County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| N&sbl Route 0081 over Laurel Spring Branch | 1963 | 33,381 | Fair |
| Interstate 81 over Nbl&sbl over Stream | 1963 | 31,442 | Fair |
| I-81 Nbl & Sbl over Rte 11 Nsrr Mfh River | 2021 | 31,084 | Good |
| Interstate 81 over Staley Creek | 1962 | 30,390 | Fair |
| Interstate 81 over N&sbl O Hutton Branch | 1963 | 29,356 | Fair |
| Route 81 over Nbl&sbl over Stream | 1964 | 27,803 | Fair |
All bridges nearby: Smyth County, VA bridge conditions · every bridge in Smyth County · Virginia bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.