US Bridges

US 20 Wb/Bstn Pst over I 495

Fair

Middlesex County, Massachusetts · 1.8 Mi. E. of Nthboro Tl. · Structure no. M060091L5DOTNBI

Built
1962
63 years old
Condition
Fair
inspected May 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
285 ft
5 main spans
Daily traffic
10,227
2023 count
Owner
State
State Highway Agency

About this bridge

US 20 Wb/Bstn Pst over I 495 is a steel stringer/multi-beam or girder carrying US 20 Wb/Bstn Pst over I 495 in Middlesex 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 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 10,227 vehicles a day, roughly 2% of them trucks, projected to reach 53,696 by 2031. The structure is 285 ft (86.9 m) long and 49 ft wide. If it were closed, the detour would be 0.6 mi (1 km).

Location

Open in Google Maps
CarriesUS 20 Wb/Bstn Pst
CrossesI 495
Location1.8 Mi. E. of Nthboro Tl.
RouteState Highway 20
CountyMiddlesex County
StateMassachusetts
Coordinates42.34123, -71.57527
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Last inspectionMay 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating59.7 US tons
Inventory rating35.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans5
Design loadH 20
Structure length285 ft (86.9 m)
Longest span76 ft (23.2 m)
Deck width49 ft (15 m)
Roadway width36 ft (11 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic10,227 (2023)
Projected traffic53,696 by 2031
Trucks2%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway and pedestrian
CrossesHighway
Detour if closed0.6 mi (1 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$3.7 million (2025 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was US 20 Wb/Bstn Pst over I 495 built?

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

What condition is US 20 Wb/Bstn Pst 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 May 2024.

How much traffic does US 20 Wb/Bstn Pst over I 495 carry?

About 10,227 vehicles per day (2023 count), of which roughly 2% are trucks.

How long is US 20 Wb/Bstn Pst over I 495?

The structure is 285 ft (86.9 m) long with a longest span of 76 ft (23.2 m) and a deck 49 ft wide.

Who owns US 20 Wb/Bstn Pst over I 495?

It is owned by the State Highway Agency.