US Bridges

Old Lake Shore RD over Gunstock River

Good

Belknap County, New Hampshire · 240 Ft FR Intervale RD · Structure no. 009101060009900

Built
1927
98 years old, rebuilt 2020
Condition
Good
inspected August 2024
Type
Slab
Prestressed Concrete
Length
46 ft
1 main span
Daily traffic
672
2023 count
Owner
City
City or Municipal Highway Agency

About this bridge

Old Lake Shore RD over Gunstock River is a prestressed concrete slab carrying Old Lake Shore RD over Gunstock River in Belknap County, New Hampshire. It was built in 1927 and reconstructed in 2020, so it is 98 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 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 672 vehicles a day, roughly 4% of them trucks, projected to reach 994 by 2043. The structure is 46 ft (14.1 m) long and 28 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesOld Lake Shore RD
CrossesGunstock River
Location240 Ft FR Intervale RD
Coordinates43.57423, -71.40185
Functional classUrban Local

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 inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating75 US tons
Inventory rating57.8 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHL 93
Structure length46 ft (14.1 m)
Longest span42 ft (12.8 m)
Deck width28 ft (8.6 m)
Roadway width24 ft (7.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic672 (2023)
Projected traffic994 by 2043
Trucks4%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal 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 Old Lake Shore RD over Gunstock River built?

It was built in 1927, making it 98 years old in 2025. It was reconstructed in 2020.

What condition is Old Lake Shore RD 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 August 2024.

How much traffic does Old Lake Shore RD over Gunstock River carry?

About 672 vehicles per day (2023 count), of which roughly 4% are trucks.

How long is Old Lake Shore RD over Gunstock River?

The structure is 46 ft (14.1 m) long with a longest span of 42 ft (12.8 m) and a deck 28 ft wide.

Who owns Old Lake Shore RD over Gunstock River?

It is owned by the City or Municipal Highway Agency.