US Bridges

I 495 NB over HWY W Main ST

Poor

Middlesex County, Massachusetts · 1.1 MI S of ST-135 · Structure no. H230111UQDOTNBI

Built
1966
59 years old
Condition
Poor
inspected July 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
140 ft
2 main spans
Daily traffic
48,152
2022 count
Owner
State
State Highway Agency

About this bridge

I 495 NB over HWY W Main ST is a steel stringer/multi-beam or girder carrying I 495 NB over HWY W Main ST in Middlesex County, Massachusetts. It was built in 1966, so it is 59 years old, younger 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 48,152 vehicles a day, roughly 6% of them trucks, projected to reach 156,207 by 2031. The structure is 140 ft (42.7 m) long and 59 ft wide. If it were closed, the detour would be 0.6 mi (1 km).

Location

Open in Google Maps
CarriesI 495 NB
CrossesHWY W Main ST
Location1.1 MI S of ST-135
RouteInterstate 495
CountyMiddlesex County
StateMassachusetts
Coordinates42.21443, -71.54577
Functional classUrban Principal Arterial - Interstate

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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJuly 2024
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 rating62.4 US tons
Inventory rating37.4 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans2
Design loadHS 20
Structure length140 ft (42.7 m)
Longest span66 ft (20.1 m)
Deck width59 ft (18.1 m)
Roadway width52 ft (16 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic48,152 (2022)
Projected traffic156,207 by 2031
Trucks6%
Lanes on structure4
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed0.6 mi (1 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$7.6 million (2025 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was I 495 NB over HWY W Main ST built?

It was built in 1966, making it 59 years old in 2025.

What condition is I 495 NB over HWY W Main ST 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 July 2024.

How much traffic does I 495 NB over HWY W Main ST carry?

About 48,152 vehicles per day (2022 count), of which roughly 6% are trucks.

How long is I 495 NB over HWY W Main ST?

The structure is 140 ft (42.7 m) long with a longest span of 66 ft (20.1 m) and a deck 59 ft wide.

Who owns I 495 NB over HWY W Main ST?

It is owned by the State Highway Agency.