US Bridges

I 495 over Comb Merrimac ST & MBTA

Fair

Essex County, Massachusetts · .32 KM S Merrimac River · Structure no. L040372XBDOTNBI

Built
1962
63 years old
Condition
Fair
inspected January 2025
Type
Stringer/Multi-beam or Girder
Steel
Length
391 ft
6 main spans
Daily traffic
96,595
2019 count
Owner
State
State Highway Agency

About this bridge

I 495 over Comb Merrimac ST & MBTA is a steel stringer/multi-beam or girder carrying I 495 over Comb Merrimac ST & MBTA in Essex County, Massachusetts. It was built in 1962, so it is 63 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 96,595 vehicles a day, roughly 12% of them trucks, projected to reach 149,718 by 2032. The structure is 391 ft (119.2 m) long and 95 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesI 495
CrossesComb Merrimac ST & MBTA
Location.32 KM S Merrimac River
RouteInterstate 495
CountyEssex County
StateMassachusetts
Coordinates42.70365, -71.13989
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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionJanuary 2025
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 geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating68.8 US tons
Inventory rating41.2 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans6
Design loadHS 20
Structure length391 ft (119.2 m)
Longest span103 ft (31.3 m)
Deck width95 ft (29 m)
Roadway width89 ft (27 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic96,595 (2019)
Projected traffic149,718 by 2032
Trucks12%
Lanes on structure6
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway and railroad
Detour if closed1.9 mi (3 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 statusPossibly eligible for the National Register; requires further investigation
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$33.9 million (2025 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was I 495 over Comb Merrimac ST & MBTA built?

It was built in 1962, making it 63 years old in 2025.

What condition is I 495 over Comb Merrimac ST & 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 January 2025.

How much traffic does I 495 over Comb Merrimac ST & MBTA carry?

About 96,595 vehicles per day (2019 count), of which roughly 12% are trucks.

How long is I 495 over Comb Merrimac ST & MBTA?

The structure is 391 ft (119.2 m) long with a longest span of 103 ft (31.3 m) and a deck 95 ft wide.

Who owns I 495 over Comb Merrimac ST & MBTA?

It is owned by the State Highway Agency.