US Bridges

US 4 over Mascoma River

Good

Grafton County, New Hampshire · 3.0 MI from Enfield Tl · Structure no. 003601370006200

Built
2004
21 years old
Condition
Good
inspected May 2024
Type
Box Beam or Girders - Multiple
Concrete
Length
67 ft
1 main span
Daily traffic
6,887
2023 count
Owner
State
State Highway Agency

About this bridge

US 4 over Mascoma River is a concrete box beam or girders - multiple carrying US 4 over Mascoma River in Grafton County, New Hampshire. It was built in 2004, so it is 21 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 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 6,887 vehicles a day, roughly 7% of them trucks, projected to reach 10,192 by 2043. The structure is 67 ft (20.4 m) long and 34 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesUS 4
CrossesMascoma River
Location3.0 MI from Enfield Tl
RouteU.S. Route 4
CountyGrafton County
StateNew Hampshire
Coordinates43.65027, -72.05941
Functional classRural Minor Arterial

Condition and inspection

Good

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

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating80.8 US tons
Inventory rating48 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 25 or greater
Structure length67 ft (20.4 m)
Longest span65 ft (19.9 m)
Deck width34 ft (10.5 m)
Roadway width31 ft (9.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,887 (2023)
Projected traffic10,192 by 2043
Trucks7%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 km)
TollOn a free road
National Highway SystemNo

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)
NavigationNo navigation control on waterway

Frequently asked questions

When was US 4 over Mascoma River built?

It was built in 2004, making it 21 years old in 2025.

What condition is US 4 over Mascoma River 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 2024.

How much traffic does US 4 over Mascoma River carry?

About 6,887 vehicles per day (2023 count), of which roughly 7% are trucks.

How long is US 4 over Mascoma River?

The structure is 67 ft (20.4 m) long with a longest span of 65 ft (19.9 m) and a deck 34 ft wide.

Who owns US 4 over Mascoma River?

It is owned by the State Highway Agency.