Bridge conditions in Loudoun County, Virginia
442 inventoried bridges · 3 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
The federal inventory lists 442 bridges in Loudoun County: 232 rated good, 207 fair, and 3 poor.
- 3 of the 442 bridges in Loudoun County, Virginia, are rated in poor condition (0.7%) in the 2025 National Bridge Inventory, as of .
- 232 bridges (52.5%) are rated good and 207 (46.8%) fair.
- The median Loudoun County bridge was built in 1995.
- The busiest poor-rated bridge is Thomas Avenue over Sugarland Run (built 1970), carrying about 1,687 vehicles a day.
Good 52.5% · Fair 46.8% · Poor 0.7% of 442 bridges
Bridges rated poor
Every bridge in the county with a poor rating, busiest first. Poor means a major component is rated 4 or lower on FHWA's 0-9 scale; it is a repair flag, not a closure notice.
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Thomas Avenue over Sugarland Run | 1970 | 1,687 | Poor |
| New Road over Bull Run | 1993 | 621 | Poor |
| Davis Court over Tuscarora Creek | 1971 | 195 | Poor |
Busiest bridges in the 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 |
| Harry Byrd Highway over Broad Run | 1969 | 71,111 | Fair |
| Dulles Greenway over Trib. Horsepen Run | 1994 | 70,185 | Fair |
| Waxpool Road over Trib. of Broad Run | 1987 | 61,481 | Good |
| Waxpool Road over Rte. 28 - Sully Road | 2004 | 61,481 | Good |
Source: FHWA National Bridge Inventory, 2025. Counts cover inventoried highway bridges over 20 feet; ratings are reported by the state DOT.
All of Virginia: Virginia bridge conditions by county · every download on the data page.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.