US Bridges

Nh 12A over Ox Brook

Good

Sullivan County, New Hampshire · 1.0 MI NW JCT 12 and 12A · Structure no. 004200640009000

Built
2002
23 years old
Condition
Good
inspected April 2024
Type
Culvert
Concrete
Length
28 ft
1 main span
Daily traffic
1,429
2023 count
Owner
State
State Highway Agency

About this bridge

Nh 12A over Ox Brook is a concrete culvert carrying Nh 12A over Ox Brook in Sullivan County, New Hampshire. It was built in 2002, so it is 23 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 1,429 vehicles a day, roughly 16% of them trucks, projected to reach 2,114 by 2043. The structure is 28 ft (8.5 m) long. If it were closed, the detour would be 3.1 mi (5 km).

CarriesNh 12A
CrossesOx Brook
Location1.0 MI NW JCT 12 and 12A
RouteState Highway 12A
Coordinates43.3105, -72.38778
Functional classRural Major Collector

Condition and inspection

Good

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

ComponentRatingMeaning
Channel and channel protection8 Very GoodNo problems noted.
Culvert7 GoodSome minor problems.
Last inspectionApril 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment4: Meets minimum tolerable limits to be left in place as is
Operating rating67.5 US tons
Inventory rating49.5 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans1
Design loadHS 25 or greater
Structure length28 ft (8.5 m)
Longest span28 ft (8.5 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,429 (2023)
Projected traffic2,114 by 2043
Trucks16%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed3.1 mi (5 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 Nh 12A over Ox Brook built?

It was built in 2002, making it 23 years old in 2025.

What condition is Nh 12A over Ox Brook 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 April 2024.

How much traffic does Nh 12A over Ox Brook carry?

About 1,429 vehicles per day (2023 count), of which roughly 16% are trucks.

How long is Nh 12A over Ox Brook?

The structure is 28 ft (8.5 m) long with a longest span of 28 ft (8.5 m).

Who owns Nh 12A over Ox Brook?

It is owned by the State Highway Agency.