WB Diaah Entrance over Horsepen Run
Loudoun County, Virginia · rated Fair in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- WB Diaah Entrance over Horsepen Run in Loudoun County, Virginia, is rated in fair condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the superstructure, rated 6 (satisfactory condition) on the 0-9 scale.
- It was built in 1997, making it 28 years old at the 2025 inventory.
- It carries about 13,000 vehicles a day (traffic count year 2024).
- It is one of 207 of the 442 inventoried bridges in Loudoun County rated fair (46.8%); 3 (0.7%) 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 February 2024, on a 24-month routine inspection cycle.
- 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 → (38.9635, -77.43092)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 7 | 7 | Good condition |
| Superstructure | 6 | 6 | Satisfactory condition |
| Substructure | 7 | 7 | Good condition |
Bridge details
| Structure | Continuous steel stringer or multi-beam girder |
| Length | about 162 ft |
| Location | 1.3 Miles From Dulles Air |
| NBI structure number | 2100030P0000000 |
| Condition class | Fair |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | February 2024 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 5: foundations stable, scour within the limits of the footing or piles |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Virginia department of transportation.
Busiest bridges in Loudoun County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Sully Road over Tributary Horsepen Run | 1963 | 184,788 | Fair |
| Sully Rd. over Cabin Branch | 1963 | 127,227 | Fair |
| Rte. 28 NB over Dulles Access Rd | 1963 | 93,735 | Fair |
| Rte. 28 SB over Dulles Access Road | 1988 | 93,735 | Good |
| Sully Road RTE.28 over Merrybrook Run | 1961 | 84,996 | Fair |
| Harry Byrd Highway over Broad Run | 1949 | 71,111 | Fair |
All bridges nearby: Loudoun County, VA bridge conditions · every bridge in Loudoun County · Virginia bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.