US Bridges

US 4 over Nhrr

Fair

Merrimack County, New Hampshire · .1 MI from Jct. I-93 · Structure no. 005200410012100

Built
1958
67 years old, rebuilt 1992
Condition
Fair
inspected May 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
95 ft
3 main spans
Daily traffic
11,598
2023 count
Owner
State
State Highway Agency

About this bridge

US 4 over Nhrr is a steel continuous stringer/multi-beam or girder carrying US 4 over Nhrr in Merrimack County, New Hampshire. It was built in 1958 and reconstructed in 1992, so it is 67 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 11,598 vehicles a day, roughly 5% of them trucks, projected to reach 17,165 by 2043. The structure is 95 ft (29 m) long and 59 ft wide. If it were closed, the detour would be 6.8 mi (11 km).

Location

Open in Google Maps
CarriesUS 4
CrossesNhrr
Location.1 MI from Jct. I-93
RouteCity Street 0
CountyMerrimack County
StateNew Hampshire
Coordinates43.29105, -71.57475
Functional classUrban Minor 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
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating99 US tons
Inventory rating61.2 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20 + Mod
Structure length95 ft (29 m)
Longest span43 ft (13.1 m)
Deck width59 ft (18 m)
Roadway width55 ft (16.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic11,598 (2023)
Projected traffic17,165 by 2043
Trucks5%
Lanes on structure3
Traffic directionTwo-way traffic
CarriesHighway
CrossesRailroad
Detour if closed6.8 mi (11 km)
TollOn a free road
National Highway SystemNo
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 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 US 4 over Nhrr built?

It was built in 1958, making it 67 years old in 2025. It was reconstructed in 1992.

What condition is US 4 over Nhrr 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 2023.

How much traffic does US 4 over Nhrr carry?

About 11,598 vehicles per day (2023 count), of which roughly 5% are trucks.

How long is US 4 over Nhrr?

The structure is 95 ft (29 m) long with a longest span of 43 ft (13.1 m) and a deck 59 ft wide.

Who owns US 4 over Nhrr?

It is owned by the State Highway Agency.