US Bridges

ST 24 NB over I 495

Fair

Plymouth County, Massachusetts · ST 24 at I 495 · Structure no. B230203MVDOTNBI

Built
1979
46 years old
Condition
Fair
inspected July 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
417 ft
2 main spans
Daily traffic
80,302
2023 count
Owner
State
State Highway Agency

About this bridge

ST 24 NB over I 495 is a steel continuous stringer/multi-beam or girder carrying ST 24 NB over I 495 in Plymouth County, Massachusetts. It was built in 1979, so it is 46 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 80,302 vehicles a day, roughly 10% of them trucks, projected to reach 60,013 by 2032. The structure is 417 ft (127.1 m) long and 59 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesST 24 NB
CrossesI 495
LocationST 24 at I 495
RouteState Highway 24
CountyPlymouth County
StateMassachusetts
Coordinates41.94683, -71.02112
Functional classUrban Principal Arterial - Other Freeway or Expressway

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.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment9: Superior to present desirable criteria
Operating rating81.4 US tons
Inventory rating48.7 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans2
Design loadHS 20 + Mod
Structure length417 ft (127.1 m)
Longest span205 ft (62.5 m)
Deck width59 ft (18 m)
Roadway width56 ft (17.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic80,302 (2023)
Projected traffic60,013 by 2032
Trucks10%
Lanes on structure4
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed3.1 mi (5 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 proposedWidening of existing bridge without deck rehabilitation
Estimated improvement cost$15 million (2025 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was ST 24 NB over I 495 built?

It was built in 1979, making it 46 years old in 2025.

What condition is ST 24 NB over I 495 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 July 2023.

How much traffic does ST 24 NB over I 495 carry?

About 80,302 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is ST 24 NB over I 495?

The structure is 417 ft (127.1 m) long with a longest span of 205 ft (62.5 m) and a deck 59 ft wide.

Who owns ST 24 NB over I 495?

It is owned by the State Highway Agency.