US Bridges

Is 495X over Cabin John Creek

Fair

Montgomery County, Maryland · 0.22 Mile North of Gv 6 · Structure no. 100000150085010

Built
1964
61 years old, rebuilt 1970
Condition
Fair
inspected April 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
289 ft
5 main spans
Daily traffic
19,820
2009 count
Owner
State
State Highway Agency

About this bridge

Is 495X over Cabin John Creek is a steel stringer/multi-beam or girder carrying Is 495X 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 19,820 vehicles a day, roughly 8% of them trucks, projected to reach 22,162 by 2026. The structure is 289 ft (88.1 m) long and 75 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

CarriesIs 495X
CrossesCabin John Creek
Location0.22 Mile North of Gv 6
RouteInterstate 495X
Coordinates38.97304, -77.14862
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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating61 US tons
Inventory rating36.5 US tons

Structure

MaterialSteel
DeckConcrete, cast-in-place
Main spans5
Design loadH 20
Structure length289 ft (88.1 m)
Longest span62 ft (18.9 m)
Deck width75 ft (22.9 m)
Roadway width70 ft (21.3 m)
Vertical clearance over deck40 ft (12.2 m)

Traffic and service

Average daily traffic19,820 (2009)
Projected traffic22,162 by 2026
Trucks8%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway
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 proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$1.4 million
NavigationNo navigation control on waterway

Frequently asked questions

When was Is 495X 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 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 April 2023.

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

About 19,820 vehicles per day (2009 count), of which roughly 8% are trucks.

How long is Is 495X over Cabin John Creek?

The structure is 289 ft (88.1 m) long with a longest span of 62 ft (18.9 m) and a deck 75 ft wide.

Who owns Is 495X over Cabin John Creek?

It is owned by the State Highway Agency.