US Bridges

Mason Hill Rd. over North Branch

Fair

Fairfax County, Virginia · 0.04FR629 0.04TO805 · Structure no. 000000000006993

Built
1969
56 years old
Condition
Fair
inspected February 2023
Type
Culvert
Concrete
Length
29 ft
3 main spans
Daily traffic
614
2009 count
Owner
State
State Highway Agency

About this bridge

Mason Hill Rd. over North Branch is a concrete culvert carrying Mason Hill Rd. over North Branch in Fairfax County, Virginia. It was built in 1969, 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 614 vehicles a day, projected to reach 725 by 2045. The structure is 29 ft (8.8 m) long. If it were closed, the detour would be 1.2 mi (2 km).

Location

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CarriesMason Hill Rd.
CrossesNorth Branch
Location0.04FR629 0.04TO805
RouteCounty Highway 4220
CountyFairfax County
StateVirginia
Coordinates38.75528, -77.05808
Functional classUrban Local

Condition and inspection

Fair

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

ComponentRatingMeaning
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionFebruary 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating71 US tons
Inventory rating43 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans3
Design loadHS 20
Structure length29 ft (8.8 m)
Longest span10 ft (3 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic614 (2009)
Projected traffic725 by 2045
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 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 proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$110 million
NavigationNo navigation control on waterway

Frequently asked questions

When was Mason Hill Rd. over North Branch built?

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

What condition is Mason Hill Rd. over North Branch 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 February 2023.

How much traffic does Mason Hill Rd. over North Branch carry?

About 614 vehicles per day (2009 count).

How long is Mason Hill Rd. over North Branch?

The structure is 29 ft (8.8 m) long with a longest span of 10 ft (3 m).

Who owns Mason Hill Rd. over North Branch?

It is owned by the State Highway Agency.