US Bridges

I-393 US 4 US202W over Portsmouth Street

Good

Merrimack County, New Hampshire · 0.7 MI E Eastside Drive · Structure no. 005201530014900

Built
1978
47 years old, rebuilt 2001
Condition
Good
inspected May 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
131 ft
1 main span
Daily traffic
16,864
2023 count
Owner
State
State Highway Agency

About this bridge

I-393 US 4 US202W over Portsmouth Street is a steel stringer/multi-beam or girder carrying I-393 US 4 US202W over Portsmouth Street in Merrimack County, New Hampshire. It was built in 1978 and reconstructed in 2001, so it is 47 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 good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 16,864 vehicles a day, roughly 6% of them trucks, projected to reach 24,958 by 2043. The structure is 131 ft (39.9 m) long and 40 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesI-393 US 4 US202W
CrossesPortsmouth Street
Location0.7 MI E Eastside Drive
RouteInterstate 393
CountyMerrimack County
StateNew Hampshire
Coordinates43.22847, -71.49448
Functional classUrban Principal Arterial - Interstate

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation7: Better than 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 rating56.9 US tons
Inventory rating34.2 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20 + Mod
Structure length131 ft (39.9 m)
Longest span118 ft (36 m)
Deck width40 ft (12.2 m)
Roadway width36 ft (11 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic16,864 (2023)
Projected traffic24,958 by 2043
Trucks6%
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-393 US 4 US202W over Portsmouth Street built?

It was built in 1978, making it 47 years old in 2025. It was reconstructed in 2001.

What condition is I-393 US 4 US202W over Portsmouth Street in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in May 2023.

How much traffic does I-393 US 4 US202W over Portsmouth Street carry?

About 16,864 vehicles per day (2023 count), of which roughly 6% are trucks.

How long is I-393 US 4 US202W over Portsmouth Street?

The structure is 131 ft (39.9 m) long with a longest span of 118 ft (36 m) and a deck 40 ft wide.

Who owns I-393 US 4 US202W over Portsmouth Street?

It is owned by the State Highway Agency.