US Bridges

Browns Mill Road over Difficult Run

Fair

Fairfax County, Virginia · 01.30FR674/00.40TO702 · Structure no. 000000000006831

Built
1969
56 years old, rebuilt 1997
Condition
Fair
inspected May 2023
Type
Slab
Prestressed Concrete
Length
55 ft
2 main spans
Daily traffic
7,632
2022 count
Owner
State
State Highway Agency

About this bridge

Browns Mill Road over Difficult Run is a prestressed concrete slab carrying Browns Mill Road over Difficult Run in Fairfax County, Virginia. It was built in 1969 and reconstructed in 1997, so it is 56 years old, older than the Virginia average of 50.7 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 7,632 vehicles a day, projected to reach 8,066 by 2045. The structure is 55 ft (16.8 m) long and 30 ft wide. If it were closed, the detour would be 11.2 mi (18 km).

Location

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CarriesBrowns Mill Road
CrossesDifficult Run
Location01.30FR674/00.40TO702
RouteCounty Highway 675
CountyFairfax County
StateVirginia
Coordinates38.95331, -77.29136
Functional classUrban Collector

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment7: Better than present minimum criteria
Operating rating84.2 US tons
Inventory rating65 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans2
Design loadHS 20
Structure length55 ft (16.8 m)
Longest span28 ft (8.5 m)
Deck width30 ft (9.1 m)
Roadway width27 ft (8.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic7,632 (2022)
Projected traffic8,066 by 2045
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed11.2 mi (18 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedWidening of existing bridge without deck rehabilitation
Estimated improvement cost$115 million
NavigationNo navigation control on waterway

Frequently asked questions

When was Browns Mill Road over Difficult Run built?

It was built in 1969, making it 56 years old in 2025. It was reconstructed in 1997.

What condition is Browns Mill Road over Difficult Run in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in May 2023.

How much traffic does Browns Mill Road over Difficult Run carry?

About 7,632 vehicles per day (2022 count).

How long is Browns Mill Road over Difficult Run?

The structure is 55 ft (16.8 m) long with a longest span of 28 ft (8.5 m) and a deck 30 ft wide.

Who owns Browns Mill Road over Difficult Run?

It is owned by the State Highway Agency.