US Bridges

I-89 SB over Stoney Brook Road

Fair

Sullivan County, New Hampshire · 1.0 MI from Sunapee T.L. · Structure no. 023900520005000

Built
1967
58 years old
Condition
Fair
inspected April 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
69 ft
1 main span
Daily traffic
9,692
2023 count
Owner
State
State Highway Agency

About this bridge

I-89 SB over Stoney Brook Road is a prestressed concrete stringer/multi-beam or girder carrying I-89 SB over Stoney Brook Road in Sullivan County, New Hampshire. It was built in 1967, so it is 58 years old, older than the New Hampshire average of 56.9 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 9,692 vehicles a day, roughly 9% of them trucks, projected to reach 14,344 by 2043. The structure is 69 ft (21 m) long and 44 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesI-89 SB
CrossesStoney Brook Road
Location1.0 MI from Sunapee T.L.
RouteInterstate 89
Coordinates43.45119, -72.08869
Functional classRural 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
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating55 US tons
Inventory rating33 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20 + Mod
Structure length69 ft (21 m)
Longest span63 ft (19.2 m)
Deck width44 ft (13.4 m)
Roadway width39 ft (11.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic9,692 (2023)
Projected traffic14,344 by 2043
Trucks9%
Lanes on structure2
Traffic directionOne-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 statusNot eligible for the National Register of Historic Places
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$314,000 (2025 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was I-89 SB over Stoney Brook Road built?

It was built in 1967, making it 58 years old in 2025.

What condition is I-89 SB over Stoney Brook Road 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 April 2023.

How much traffic does I-89 SB over Stoney Brook Road carry?

About 9,692 vehicles per day (2023 count), of which roughly 9% are trucks.

How long is I-89 SB over Stoney Brook Road?

The structure is 69 ft (21 m) long with a longest span of 63 ft (19.2 m) and a deck 44 ft wide.

Who owns I-89 SB over Stoney Brook Road?

It is owned by the State Highway Agency.