US Bridges

Carderock Access C over Clara Barton Parkway

Fair

Montgomery County, Maryland · 0.7 Miles West of Macarth · Structure no. 3300030P0000000

Built
1962
63 years old, rebuilt 1991
Condition
Fair
inspected April 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
118 ft
1 main span
Daily traffic
2,000
2013 count
Owner
Federal
National Park Service

About this bridge

Carderock Access C over Clara Barton Parkway is a prestressed concrete stringer/multi-beam or girder carrying Carderock Access C over Clara Barton Parkway in Montgomery County, Maryland. It was built in 1962 and reconstructed in 1991, so it is 63 years old, older than the Maryland average of 52.6 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 5 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 2,000 vehicles a day, roughly 20% of them trucks, projected to reach 2,200 by 2033. The structure is 118 ft (35.9 m) long and 47 ft wide.

Location

Open in Google Maps
CarriesCarderock Access C
CrossesClara Barton Parkway
Location0.7 Miles West of Macarth
RouteFederal Lands Road 6
CountyMontgomery County
StateMaryland
Coordinates38.97272, -77.19539
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating36 US tons
Inventory rating20.9 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadH 20
Structure length118 ft (35.9 m)
Longest span111 ft (33.8 m)
Deck width47 ft (14.2 m)
Roadway width36 ft (11 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,000 (2013)
Projected traffic2,200 by 2033
Trucks20%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesHighway
Detour if closed—
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerNational Park Service
Maintained byNational Park Service
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost$398,000 (2021 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was Carderock Access C over Clara Barton Parkway built?

It was built in 1962, making it 63 years old in 2025. It was reconstructed in 1991.

What condition is Carderock Access C over Clara Barton Parkway 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 April 2023.

How much traffic does Carderock Access C over Clara Barton Parkway carry?

About 2,000 vehicles per day (2013 count), of which roughly 20% are trucks.

How long is Carderock Access C over Clara Barton Parkway?

The structure is 118 ft (35.9 m) long with a longest span of 111 ft (33.8 m) and a deck 47 ft wide.

Who owns Carderock Access C over Clara Barton Parkway?

It is owned by the National Park Service.