US Bridges

NH151 over I-95

Fair

Rockingham County, New Hampshire · 1.1 MI JCT 101D · Structure no. 019700990014400

Built
1975
50 years old
Condition
Fair
inspected July 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
351 ft
2 main spans
Daily traffic
3,412
2023 count
Owner
Toll Authority
State Toll Authority

About this bridge

NH151 over I-95 is a steel continuous stringer/multi-beam or girder carrying NH151 over I-95 in Rockingham County, New Hampshire. It was built in 1975, so it is 50 years old, younger 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 3,412 vehicles a day, roughly 10% of them trucks, projected to reach 5,049 by 2043. The structure is 351 ft (107 m) long and 57 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesNH151
CrossesI-95
Location1.1 MI JCT 101D
RouteState Highway 1B
CountyRockingham County
StateNew Hampshire
Coordinates42.99439, -70.84837
Functional classUrban Collector

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.
Substructure7 GoodSome minor problems.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating38.5 US tons
Inventory rating29.7 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans2
Design loadHS 20 + Mod
Structure length351 ft (107 m)
Longest span176 ft (53.6 m)
Deck width57 ft (17.3 m)
Roadway width44 ft (13.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,412 (2023)
Projected traffic5,049 by 2043
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesHighway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Toll Authority
Maintained byState Toll Authority
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 NH151 over I-95 built?

It was built in 1975, making it 50 years old in 2025.

What condition is NH151 over I-95 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 July 2023.

How much traffic does NH151 over I-95 carry?

About 3,412 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is NH151 over I-95?

The structure is 351 ft (107 m) long with a longest span of 176 ft (53.6 m) and a deck 57 ft wide.

Who owns NH151 over I-95?

It is owned by the State Toll Authority.