US Bridges

Md 355 SB over Is 495 Il

Fair

Montgomery County, Maryland · 1.31 Miles S of Md 547 · Structure no. 100000150120010

Built
1959
66 years old, rebuilt 1997
Condition
Fair
inspected October 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
294 ft
3 main spans
Daily traffic
55,020
2009 count
Owner
State
State Highway Agency

About this bridge

Md 355 SB over Is 495 Il is a steel stringer/multi-beam or girder carrying Md 355 SB over Is 495 Il in Montgomery County, Maryland. It was built in 1959 and reconstructed in 1997, so it is 66 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 55,020 vehicles a day, roughly 8% of them trucks, projected to reach 39,969 by 2026. The structure is 294 ft (89.6 m) long and 54 ft wide. If it were closed, the detour would be 5 mi (8 km).

Location

Open in Google Maps
CarriesMd 355 SB
CrossesIs 495 Il
Location1.31 Miles S of Md 547
RouteState Highway 355
CountyMontgomery County
StateMaryland
Coordinates39.01739, -77.10206
Functional classUrban Other Principal Arterial

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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionOctober 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 geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating36.5 US tons
Inventory rating22 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length294 ft (89.6 m)
Longest span138 ft (42.1 m)
Deck width54 ft (16.4 m)
Roadway width48 ft (14.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic55,020 (2009)
Projected traffic39,969 by 2026
Trucks8%
Lanes on structure3
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed5 mi (8 km)
TollOn a free road
National Highway SystemYes

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 million
NavigationNot applicable (no waterway)

Frequently asked questions

When was Md 355 SB over Is 495 Il built?

It was built in 1959, making it 66 years old in 2025. It was reconstructed in 1997.

What condition is Md 355 SB over Is 495 Il 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 October 2023.

How much traffic does Md 355 SB over Is 495 Il carry?

About 55,020 vehicles per day (2009 count), of which roughly 8% are trucks.

How long is Md 355 SB over Is 495 Il?

The structure is 294 ft (89.6 m) long with a longest span of 138 ft (42.1 m) and a deck 54 ft wide.

Who owns Md 355 SB over Is 495 Il?

It is owned by the State Highway Agency.