US Bridges

I 91 NB over ST 9 Bridge ST

Fair

Hampshire County, Massachusetts · Mm 24.8 on I-91 NB · Structure no. N19062106DOTNBI

Built
1965
60 years old
Condition
Fair
inspected June 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
162 ft
4 main spans
Daily traffic
23,875
2017 count
Owner
State
State Highway Agency

About this bridge

I 91 NB over ST 9 Bridge ST is a steel stringer/multi-beam or girder carrying I 91 NB over ST 9 Bridge ST in Hampshire County, Massachusetts. It was built in 1965, so it is 60 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. Its operating status is: open, would be posted or closed except for temporary shoring.

It carries about 23,875 vehicles a day, roughly 12% of them trucks, projected to reach 19,031 by 2031. The structure is 162 ft (49.3 m) long and 44 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesI 91 NB
CrossesST 9 Bridge ST
LocationMm 24.8 on I-91 NB
RouteInterstate 91
CountyHampshire County
StateMassachusetts
Coordinates42.33319, -72.62119
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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusOpen, would be posted or closed except for temporary shoring
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating63.7 US tons
Inventory rating38.1 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20 + Mod
Structure length162 ft (49.3 m)
Longest span51 ft (15.5 m)
Deck width44 ft (13.5 m)
Roadway width38 ft (11.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic23,875 (2017)
Projected traffic19,031 by 2031
Trucks12%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed1.2 mi (2 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 proposedWidening of existing bridge without deck rehabilitation
Estimated improvement cost$2.1 million (2025 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was I 91 NB over ST 9 Bridge ST built?

It was built in 1965, making it 60 years old in 2025.

What condition is I 91 NB over ST 9 Bridge ST 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 June 2024.

How much traffic does I 91 NB over ST 9 Bridge ST carry?

About 23,875 vehicles per day (2017 count), of which roughly 12% are trucks.

How long is I 91 NB over ST 9 Bridge ST?

The structure is 162 ft (49.3 m) long with a longest span of 51 ft (15.5 m) and a deck 44 ft wide.

Who owns I 91 NB over ST 9 Bridge ST?

It is owned by the State Highway Agency.