US Bridges

HWY Southmptn ST over I 93 /US1/ST3

Fair

Suffolk County, Massachusetts · 1.1 KM S of JCT I90&93 · Structure no. B162723F6DOTNBI

Built
1958
67 years old, rebuilt 1983
Condition
Fair
inspected March 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
278 ft
4 main spans
Daily traffic
32,327
2024 count
Owner
State
State Highway Agency

About this bridge

HWY Southmptn ST over I 93 /US1/ST3 is a steel stringer/multi-beam or girder carrying HWY Southmptn ST over I 93 /US1/ST3 in Suffolk County, Massachusetts. It was built in 1958 and reconstructed in 1983, so it is 67 years old, older 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 32,327 vehicles a day, roughly 10% of them trucks, projected to reach 61,909 by 2031. The structure is 278 ft (84.7 m) long and 70 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesHWY Southmptn ST
CrossesI 93 /US1/ST3
Location1.1 KM S of JCT I90&93
RouteCity Street 0
CountySuffolk County
StateMassachusetts
Coordinates42.33034, -71.06127
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMarch 2024
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 geometry9: Superior to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating47.3 US tons
Inventory rating41.6 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length278 ft (84.7 m)
Longest span91 ft (27.7 m)
Deck width70 ft (21.3 m)
Roadway width54 ft (16.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic32,327 (2024)
Projected traffic61,909 by 2031
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesHighway
Detour if closed1.2 mi (2 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$17.6 million (2025 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was HWY Southmptn ST over I 93 /US1/ST3 built?

It was built in 1958, making it 67 years old in 2025. It was reconstructed in 1983.

What condition is HWY Southmptn ST over I 93 /US1/ST3 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 March 2024.

How much traffic does HWY Southmptn ST over I 93 /US1/ST3 carry?

About 32,327 vehicles per day (2024 count), of which roughly 10% are trucks.

How long is HWY Southmptn ST over I 93 /US1/ST3?

The structure is 278 ft (84.7 m) long with a longest span of 91 ft (27.7 m) and a deck 70 ft wide.

Who owns HWY Southmptn ST over I 93 /US1/ST3?

It is owned by the State Highway Agency.