US Bridges

Gunston Road over Unknown Creek

Good

Fairfax County, Virginia · 173.5 NE of Wills RD · Structure no. DAPMDWBEL0000C1

Built
1935
90 years old
Condition
Good
inspected August 2024
Type
Culvert
Concrete
Length
29 ft
3 main spans
Daily traffic
1,000
2020 count
Owner
Federal
Army

About this bridge

Gunston Road over Unknown Creek is a concrete culvert carrying Gunston Road over Unknown Creek in Fairfax County, Virginia. It was built in 1935, so it is 90 years old, older than the Virginia average of 50.7 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 1,000 vehicles a day, roughly 10% of them trucks, projected to reach 2,000 by 2046. The structure is 29 ft (8.9 m) long. If it were closed, the detour would be 14.3 mi (23 km).

CarriesGunston Road
CrossesUnknown Creek
Location173.5 NE of Wills RD
Coordinates38.71755, -77.15301
Functional classUrban Local

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Culvert7 GoodSome minor problems.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating36 US tons
Inventory rating21.6 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans3
Design loadUnknown
Structure length29 ft (8.9 m)
Longest span9 ft (2.8 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,000 (2020)
Projected traffic2,000 by 2046
Trucks10%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed14.3 mi (23 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerArmy
Maintained byArmy
Historic statusNot eligible for the National Register of Historic Places
Work proposedOther structural work, including hydraulic replacements
Estimated improvement cost$2,000 (2024 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was Gunston Road over Unknown Creek built?

It was built in 1935, making it 90 years old in 2025.

What condition is Gunston Road over Unknown Creek in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in August 2024.

How much traffic does Gunston Road over Unknown Creek carry?

About 1,000 vehicles per day (2020 count), of which roughly 10% are trucks.

How long is Gunston Road over Unknown Creek?

The structure is 29 ft (8.9 m) long with a longest span of 9 ft (2.8 m).

Who owns Gunston Road over Unknown Creek?

It is owned by the Army.