US Bridges

Stone Road over Ayers Brook

Good

Belknap County, New Hampshire · 4.32MI. RTE 107 · Structure no. 009201190004300

Built
1999
26 years old
Condition
Good
inspected August 2023
Type
Culvert
Aluminum, Wrought Iron, or Cast Iron
Length
25 ft
1 main span
Daily traffic
96
2023 count
Owner
City
City or Municipal Highway Agency

About this bridge

Stone Road over Ayers Brook is a aluminum, wrought iron, or cast iron culvert carrying Stone Road over Ayers Brook in Belknap County, New Hampshire. It was built in 1999, so it is 26 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 96 vehicles a day, roughly 4% of them trucks, projected to reach 142 by 2043. The structure is 25 ft (7.7 m) long. If it were closed, the detour would be 3.1 mi (5 km).

CarriesStone Road
CrossesAyers Brook
Location4.32MI. RTE 107
Coordinates43.40095, -71.30876
Functional classRural Local

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 protection7 GoodSome minor problems.
Culvert8 Very GoodNo problems noted.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating92.7 US tons
Inventory rating55.6 US tons

Structure

Structure typeCulvert
MaterialAluminum, Wrought Iron, or Cast Iron
DeckNot applicable
Main spans1
Design loadHS 25 or greater
Structure length25 ft (7.7 m)
Longest span25 ft (7.7 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic96 (2023)
Projected traffic142 by 2043
Trucks4%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal 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 Stone Road over Ayers Brook built?

It was built in 1999, making it 26 years old in 2025.

What condition is Stone Road over Ayers 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 August 2023.

How much traffic does Stone Road over Ayers Brook carry?

About 96 vehicles per day (2023 count), of which roughly 4% are trucks.

How long is Stone Road over Ayers Brook?

The structure is 25 ft (7.7 m) long with a longest span of 25 ft (7.7 m).

Who owns Stone Road over Ayers Brook?

It is owned by the City or Municipal Highway Agency.