US Bridges

ST 3 SB over I 93

Poor

Norfolk County, Massachusetts · ST 3 at I 93 · Structure no. B2102934ADOTNBI

Built
1957
68 years old, rebuilt 1978
Condition
Poor
inspected October 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
190 ft
3 main spans
Daily traffic
41,600
2023 count
Owner
State
State Highway Agency

About this bridge

ST 3 SB over I 93 is a steel stringer/multi-beam or girder carrying ST 3 SB over I 93 in Norfolk County, Massachusetts. It was built in 1957 and reconstructed in 1978, so it is 68 years old, older than the Massachusetts average of 63.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 41,600 vehicles a day, roughly 4% of them trucks, projected to reach 216,364 by 2032. The structure is 190 ft (57.9 m) long and 47 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesST 3 SB
CrossesI 93
LocationST 3 at I 93
RouteState Highway 3
CountyNorfolk County
StateMassachusetts
Coordinates42.22696, -71.02042
Functional classUrban Principal Arterial - Other Freeway or Expressway

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Last inspectionOctober 2023
Inspection intervalevery 12 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry2: Basically intolerable, requiring high priority of replacement
Approach roadway alignment8: Equal to present desirable criteria
Operating rating72 US tons
Inventory rating43.1 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans3
Design loadH 20
Structure length190 ft (57.9 m)
Longest span93 ft (28.3 m)
Deck width47 ft (14.4 m)
Roadway width42 ft (12.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic41,600 (2023)
Projected traffic216,364 by 2032
Trucks4%
Lanes on structure3
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed1.9 mi (3 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$8.1 million (2025 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was ST 3 SB over I 93 built?

It was built in 1957, making it 68 years old in 2025. It was reconstructed in 1978.

What condition is ST 3 SB over I 93 in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in October 2023.

How much traffic does ST 3 SB over I 93 carry?

About 41,600 vehicles per day (2023 count), of which roughly 4% are trucks.

How long is ST 3 SB over I 93?

The structure is 190 ft (57.9 m) long with a longest span of 93 ft (28.3 m) and a deck 47 ft wide.

Who owns ST 3 SB over I 93?

It is owned by the State Highway Agency.