US Bridges

Brook Road over Salmon Brook

Poor

Belknap County, New Hampshire · 0.1 MI from Hale RD · Structure no. 023101180008900

Built
1900
125 years old, rebuilt 2012
Condition
Poor
inspected November 2024
Type
Slab
Concrete
Length
35 ft
1 main span
Daily traffic
96
2023 count
Owner
City
City or Municipal Highway Agency

About this bridge

Brook Road over Salmon Brook is a concrete slab carrying Brook Road over Salmon Brook in Belknap County, New Hampshire. It was built in 1900 and reconstructed in 2012, so it is 125 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 poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 96 vehicles a day, roughly 4% of them trucks, projected to reach 142 by 2043. The structure is 35 ft (10.7 m) long and 16 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesBrook Road
CrossesSalmon Brook
Location0.1 MI from Hale RD
Coordinates43.51439, -71.62141
Functional classRural Local

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionNovember 2024
Inspection intervalevery 16 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 geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating83.4 US tons
Inventory rating50 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, precast panels
Main spans1
Design loadHL 93
Structure length35 ft (10.7 m)
Longest span23 ft (7 m)
Deck width16 ft (4.9 m)
Roadway width13 ft (4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic96 (2023)
Projected traffic142 by 2043
Trucks4%
Lanes on structure1
Traffic directionOne-lane bridge for two-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 Brook Road over Salmon Brook built?

It was built in 1900, making it 125 years old in 2025. It was reconstructed in 2012.

What condition is Brook Road over Salmon Brook in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in November 2024.

How much traffic does Brook Road over Salmon Brook carry?

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

How long is Brook Road over Salmon Brook?

The structure is 35 ft (10.7 m) long with a longest span of 23 ft (7 m) and a deck 16 ft wide.

Who owns Brook Road over Salmon Brook?

It is owned by the City or Municipal Highway Agency.