US Bridges

Nh 11 over Gunstock River

Good

Belknap County, New Hampshire · 2.6 MI NE Laconia Tl · Structure no. 009101020009900

Built
1958
67 years old, rebuilt 2023
Condition
Good
inspected May 2023
Type
Frame
Concrete
Length
23 ft
1 main span
Daily traffic
7,313
2023 count
Owner
State
State Highway Agency

About this bridge

Nh 11 over Gunstock River is a concrete frame carrying Nh 11 over Gunstock River in Belknap County, New Hampshire. It was built in 1958 and reconstructed in 2023, so it is 67 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 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 7,313 vehicles a day, roughly 7% of them trucks, projected to reach 10,823 by 2043. The structure is 23 ft (7 m) long and 47 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

CarriesNh 11
CrossesGunstock River
Location2.6 MI NE Laconia Tl
RouteState Highway 11
Coordinates43.5763, -71.40318
Functional classUrban 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
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating51.7 US tons
Inventory rating31 US tons

Structure

Structure typeFrame
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length23 ft (7 m)
Longest span20 ft (6.1 m)
Deck width47 ft (14.3 m)
Roadway width44 ft (13.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic7,313 (2023)
Projected traffic10,823 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 SystemNo

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 Nh 11 over Gunstock River built?

It was built in 1958, making it 67 years old in 2025. It was reconstructed in 2023.

What condition is Nh 11 over Gunstock 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 2023.

How much traffic does Nh 11 over Gunstock River carry?

About 7,313 vehicles per day (2023 count), of which roughly 7% are trucks.

How long is Nh 11 over Gunstock River?

The structure is 23 ft (7 m) long with a longest span of 20 ft (6.1 m) and a deck 47 ft wide.

Who owns Nh 11 over Gunstock River?

It is owned by the State Highway Agency.