US Bridges

I 93 SB over Comb I90 & AMTRAK

Fair

Suffolk County, Massachusetts · Unit 4 · Structure no. B166569Q6DOTNBI

Built
2000
25 years old
Condition
Fair
inspected August 2023
Type
Segmental Box Girder
Prestressed Concrete Continuous
Length
634 ft
4 main spans
Daily traffic
116,881
2018 count
Owner
State
State Highway Agency

About this bridge

I 93 SB over Comb I90 & AMTRAK is a prestressed concrete continuous segmental box girder carrying I 93 SB over Comb I90 & AMTRAK in Suffolk County, Massachusetts. It was built in 2000, so it is 25 years old, younger than the Massachusetts average of 63.8 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 116,881 vehicles a day, roughly 9% of them trucks, projected to reach 144,980 by 2032. The structure is 634 ft (193.2 m) long and 57 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesI 93 SB
CrossesComb I90 & AMTRAK
LocationUnit 4
RouteInterstate 93
CountySuffolk County
StateMassachusetts
Coordinates42.34624, -71.06091
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
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.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry2: Basically intolerable, requiring high priority of replacement
Approach roadway alignment8: Equal to present desirable criteria
Operating rating91.5 US tons
Inventory rating54.8 US tons

Structure

Structure typeSegmental Box Girder
MaterialPrestressed Concrete Continuous
DeckOther
Main spans4
Design loadHS 20
Structure length634 ft (193.2 m)
Longest span205 ft (62.6 m)
Deck width57 ft (17.5 m)
Roadway width55 ft (16.8 m)
Vertical clearance over deck17 ft (5.2 m)

Traffic and service

Average daily traffic116,881 (2018)
Projected traffic144,980 by 2032
Trucks9%
Lanes on structure5
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway and railroad
Detour if closed1.2 mi (2 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 statusHistorical significance not determinable at this time
Work proposedWidening with deck rehabilitation or replacement
Estimated improvement cost$67.3 million (2025 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was I 93 SB over Comb I90 & AMTRAK built?

It was built in 2000, making it 25 years old in 2025.

What condition is I 93 SB over Comb I90 & AMTRAK 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 August 2023.

How much traffic does I 93 SB over Comb I90 & AMTRAK carry?

About 116,881 vehicles per day (2018 count), of which roughly 9% are trucks.

How long is I 93 SB over Comb I90 & AMTRAK?

The structure is 634 ft (193.2 m) long with a longest span of 205 ft (62.6 m) and a deck 57 ft wide.

Who owns I 93 SB over Comb I90 & AMTRAK?

It is owned by the State Highway Agency.