US Bridges

Is 495X SB over Cabin John Creek

Fair

Montgomery County, Maryland · 0.02 Mile South of Gv 6 · Structure no. 100000150086010

Built
1964
61 years old, rebuilt 1970
Condition
Fair
inspected May 2024
Type
Box Beam or Girders - Multiple
Concrete Continuous
Length
253 ft
3 main spans
Daily traffic
22,160
2012 count
Owner
State
State Highway Agency

About this bridge

Is 495X SB over Cabin John Creek is a concrete continuous box beam or girders - multiple carrying Is 495X SB over Cabin John Creek in Montgomery County, Maryland. It was built in 1964 and reconstructed in 1970, so it is 61 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 22,160 vehicles a day, roughly 8% of them trucks, projected to reach 27,700 by 2032. The structure is 253 ft (77.1 m) long and 36 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

CarriesIs 495X SB
CrossesCabin John Creek
Location0.02 Mile South of Gv 6
RouteInterstate 495X
Coordinates38.97049, -77.14689
Functional classUrban Principal Arterial - Other Freeway or Expressway

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMay 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
Deck geometry9: Superior to present desirable criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating97.4 US tons
Inventory rating58.5 US tons

Structure

MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 20
Structure length253 ft (77.1 m)
Longest span104 ft (31.7 m)
Deck width36 ft (11 m)
Roadway width27 ft (8.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic22,160 (2012)
Projected traffic27,700 by 2032
Trucks8%
Lanes on structure1
Traffic directionOne-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed3.1 mi (5 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

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$601,000
NavigationNo navigation control on waterway

Frequently asked questions

When was Is 495X SB over Cabin John Creek built?

It was built in 1964, making it 61 years old in 2025. It was reconstructed in 1970.

What condition is Is 495X SB over Cabin John Creek 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 2024.

How much traffic does Is 495X SB over Cabin John Creek carry?

About 22,160 vehicles per day (2012 count), of which roughly 8% are trucks.

How long is Is 495X SB over Cabin John Creek?

The structure is 253 ft (77.1 m) long with a longest span of 104 ft (31.7 m) and a deck 36 ft wide.

Who owns Is 495X SB over Cabin John Creek?

It is owned by the State Highway Agency.