US Bridges

Is 270 over Is 370 and Ramp B

Fair

Montgomery County, Maryland · 1.53 Mile South of Md 117 · Structure no. 100000150157010

Built
1989
36 years old
Condition
Fair
inspected October 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
311 ft
2 main spans
Daily traffic
216,270
2009 count
Owner
State
State Highway Agency

About this bridge

Is 270 over Is 370 and Ramp B is a steel continuous stringer/multi-beam or girder carrying Is 270 over Is 370 and Ramp B in Montgomery County, Maryland. It was built in 1989, so it is 36 years old, younger 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 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 216,270 vehicles a day, roughly 8% of them trucks, projected to reach 224,187 by 2026. The structure is 311 ft (94.8 m) long and 213 ft wide.

Location

Open in Google Maps
CarriesIs 270
CrossesIs 370 and Ramp B
Location1.53 Mile South of Md 117
RouteInterstate 270
CountyMontgomery County
StateMaryland
Coordinates39.1212, -77.19782
Functional classUrban Principal Arterial - Interstate

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.
Substructure7 GoodSome minor problems.
Last inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating88 US tons
Inventory rating52.5 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans2
Design loadHS 20 + Mod
Structure length311 ft (94.8 m)
Longest span154 ft (46.9 m)
Deck width213 ft (64.8 m)
Roadway width209 ft (63.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic216,270 (2009)
Projected traffic224,187 by 2026
Trucks8%
Lanes on structure12
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed—
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 proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was Is 270 over Is 370 and Ramp B built?

It was built in 1989, making it 36 years old in 2025.

What condition is Is 270 over Is 370 and Ramp B 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 2024.

How much traffic does Is 270 over Is 370 and Ramp B carry?

About 216,270 vehicles per day (2009 count), of which roughly 8% are trucks.

How long is Is 270 over Is 370 and Ramp B?

The structure is 311 ft (94.8 m) long with a longest span of 154 ft (46.9 m) and a deck 213 ft wide.

Who owns Is 270 over Is 370 and Ramp B?

It is owned by the State Highway Agency.