US Bridges

US 4 over Oyster River

Fair

Strafford County, New Hampshire · .2 MI from JCT Rt 25 · Structure no. 014501060012600

Built
1929
96 years old, rebuilt 2012
Condition
Fair
inspected July 2024
Type
Frame
Concrete
Length
24 ft
1 main span
Daily traffic
18,654
2023 count
Owner
State
State Highway Agency

About this bridge

US 4 over Oyster River is a concrete frame carrying US 4 over Oyster River in Strafford County, New Hampshire. It was built in 1929 and reconstructed in 2012, so it is 96 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 18,654 vehicles a day, roughly 7% of them trucks, projected to reach 27,607 by 2043. The structure is 24 ft (7.3 m) long and 48 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesUS 4
CrossesOyster River
Location.2 MI from JCT Rt 25
RouteU.S. Route 4
CountyStrafford County
StateNew Hampshire
Coordinates43.14847, -71.00045
Functional classRural Principal Arterial - Other

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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry9: Superior to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating52 US tons
Inventory rating31 US tons

Structure

Structure typeFrame
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadH 15
Structure length24 ft (7.3 m)
Longest span21 ft (6.4 m)
Deck width48 ft (14.6 m)
Roadway width47 ft (14.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic18,654 (2023)
Projected traffic27,607 by 2043
Trucks7%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemYes

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)
NavigationNo navigation control on waterway

Frequently asked questions

When was US 4 over Oyster River built?

It was built in 1929, making it 96 years old in 2025. It was reconstructed in 2012.

What condition is US 4 over Oyster River 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 2024.

How much traffic does US 4 over Oyster River carry?

About 18,654 vehicles per day (2023 count), of which roughly 7% are trucks.

How long is US 4 over Oyster River?

The structure is 24 ft (7.3 m) long with a longest span of 21 ft (6.4 m) and a deck 48 ft wide.

Who owns US 4 over Oyster River?

It is owned by the State Highway Agency.