US Bridges

I-93 SB US 4 Ramp over Nhrr

Fair

Merrimack County, New Hampshire · 0.1 MI S. Canterbury T/L · Structure no. 005200420012100

Built
1958
67 years old, rebuilt 1984
Condition
Fair
inspected May 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
127 ft
3 main spans
Daily traffic
6,898
2023 count
Owner
State
State Highway Agency

About this bridge

I-93 SB US 4 Ramp over Nhrr is a steel continuous stringer/multi-beam or girder carrying I-93 SB US 4 Ramp over Nhrr in Merrimack County, New Hampshire. It was built in 1958 and reconstructed in 1984, 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 5 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 6,898 vehicles a day, roughly 5% of them trucks, projected to reach 10,209 by 2043. The structure is 127 ft (38.7 m) long and 37 ft wide.

Location

Open in Google Maps
CarriesI-93 SB US 4 Ramp
CrossesNhrr
Location0.1 MI S. Canterbury T/L
CountyMerrimack County
StateNew Hampshire
Coordinates43.29024, -71.57412
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
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating58.3 US tons
Inventory rating34.9 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20 + Mod
Structure length127 ft (38.7 m)
Longest span47 ft (14.3 m)
Deck width37 ft (11.2 m)
Roadway width32 ft (9.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,898 (2023)
Projected traffic10,209 by 2043
Trucks5%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesRailroad
Detour if closed—
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-93 SB US 4 Ramp over Nhrr built?

It was built in 1958, making it 67 years old in 2025. It was reconstructed in 1984.

What condition is I-93 SB US 4 Ramp 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 I-93 SB US 4 Ramp over Nhrr carry?

About 6,898 vehicles per day (2023 count), of which roughly 5% are trucks.

How long is I-93 SB US 4 Ramp over Nhrr?

The structure is 127 ft (38.7 m) long with a longest span of 47 ft (14.3 m) and a deck 37 ft wide.

Who owns I-93 SB US 4 Ramp over Nhrr?

It is owned by the State Highway Agency.