US Bridges

US 1 Ramp S-Tb over Comb Rmp NS Ct Tl&mbta

Fair

Suffolk County, Massachusetts · I93/US1 Interchange · Structure no. B166118Y3DOTNBI

Built
2001
24 years old
Condition
Fair
inspected September 2022
Type
Segmental Box Girder
Prestressed Concrete Continuous
Length
697 ft
5 main spans
Daily traffic
15,137
2021 count
Owner
State
State Highway Agency

About this bridge

US 1 Ramp S-Tb over Comb Rmp NS Ct Tl&mbta is a prestressed concrete continuous segmental box girder carrying US 1 Ramp S-Tb over Comb Rmp NS Ct Tl&mbta in Suffolk County, Massachusetts. It was built in 2001, so it is 24 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 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 15,137 vehicles a day, roughly 2% of them trucks, projected to reach 18,162 by 2031. The structure is 697 ft (212.4 m) long and 29 ft wide. If it were closed, the detour would be 2.5 mi (4 km).

Location

Open in Google Maps
CarriesUS 1 Ramp S-Tb
CrossesComb Rmp NS Ct Tl&mbta
LocationI93/US1 Interchange
RouteInterstate 93
CountySuffolk County
StateMassachusetts
Coordinates42.37228, -71.06866
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Last inspectionSeptember 2022
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating110.1 US tons
Inventory rating63.1 US tons

Structure

Structure typeSegmental Box Girder
MaterialPrestressed Concrete Continuous
DeckOther
Main spans5
Design loadHS 20
Structure length697 ft (212.4 m)
Longest span163 ft (49.7 m)
Deck width29 ft (8.8 m)
Roadway width25 ft (7.6 m)
Vertical clearance over deck16 ft (4.9 m)

Traffic and service

Average daily traffic15,137 (2021)
Projected traffic18,162 by 2031
Trucks2%
Lanes on structure1
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway and railroad
Detour if closed2.5 mi (4 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 of existing bridge without deck rehabilitation
Estimated improvement cost$1.5 million (2025 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was US 1 Ramp S-Tb over Comb Rmp NS Ct Tl&mbta built?

It was built in 2001, making it 24 years old in 2025.

What condition is US 1 Ramp S-Tb over Comb Rmp NS Ct Tl&mbta 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 September 2022.

How much traffic does US 1 Ramp S-Tb over Comb Rmp NS Ct Tl&mbta carry?

About 15,137 vehicles per day (2021 count), of which roughly 2% are trucks.

How long is US 1 Ramp S-Tb over Comb Rmp NS Ct Tl&mbta?

The structure is 697 ft (212.4 m) long with a longest span of 163 ft (49.7 m) and a deck 29 ft wide.

Who owns US 1 Ramp S-Tb over Comb Rmp NS Ct Tl&mbta?

It is owned by the State Highway Agency.