US Bridges

Narrows Road over Suncook Lake Channel

Fair

Belknap County, New Hampshire · 0.4 MI FR White Oak RD · Structure no. 001401210014500

Built
1960
65 years old
Condition
Fair
inspected September 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
36 ft
1 main span
Daily traffic
303
2023 count
Owner
City
City or Municipal Highway Agency

About this bridge

Narrows Road over Suncook Lake Channel is a steel stringer/multi-beam or girder carrying Narrows Road over Suncook Lake Channel in Belknap County, New Hampshire. It was built in 1960, so it is 65 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 fair condition with a lowest component rating of 5 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 303 vehicles a day, projected to reach 448 by 2043. The structure is 36 ft (11 m) long and 27 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Location

Open in Google Maps
CarriesNarrows Road
CrossesSuncook Lake Channel
Location0.4 MI FR White Oak RD
CountyBelknap County
StateNew Hampshire
Coordinates43.38085, -71.27382
Functional classRural Local

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating24 US tons
Inventory rating14 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadH 15
Structure length36 ft (11 m)
Longest span33 ft (10.1 m)
Deck width27 ft (8.3 m)
Roadway width24 ft (7.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic303 (2023)
Projected traffic448 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 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 Narrows Road over Suncook Lake Channel built?

It was built in 1960, making it 65 years old in 2025.

What condition is Narrows Road over Suncook Lake Channel in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in September 2024.

How much traffic does Narrows Road over Suncook Lake Channel carry?

About 303 vehicles per day (2023 count).

How long is Narrows Road over Suncook Lake Channel?

The structure is 36 ft (11 m) long with a longest span of 33 ft (10.1 m) and a deck 27 ft wide.

Who owns Narrows Road over Suncook Lake Channel?

It is owned by the City or Municipal Highway Agency.