US Bridges

Mountain Road over Cold Brook

Fair

Carroll County, New Hampshire · 0.7 Mi. RTE.25 · Structure no. 025201680007000

Built
1900
125 years old, rebuilt 2024
Condition
Fair
inspected November 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
34 ft
1 main span
Daily traffic
41
2022 count
Owner
City
City or Municipal Highway Agency

About this bridge

Mountain Road over Cold Brook is a steel stringer/multi-beam or girder carrying Mountain Road over Cold Brook in Carroll County, New Hampshire. It was built in 1900 and reconstructed in 2024, 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 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 41 vehicles a day, roughly 4% of them trucks, projected to reach 60 by 2042. The structure is 34 ft (10.4 m) long and 17 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

Location

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CarriesMountain Road
CrossesCold Brook
Location0.7 Mi. RTE.25
CountyCarroll County
StateNew Hampshire
Coordinates43.81616, -71.29691
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
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionNovember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry8: Equal to present desirable criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment4: Meets minimum tolerable limits to be left in place as is
Operating rating41.9 US tons
Inventory rating25.2 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckWood or timber
Main spans1
Design loadUnknown
Structure length34 ft (10.4 m)
Longest span31 ft (9.4 m)
Deck width17 ft (5.3 m)
Roadway width16 ft (4.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic41 (2022)
Projected traffic60 by 2042
Trucks4%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.8 mi (159 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 Mountain Road over Cold Brook built?

It was built in 1900, making it 125 years old in 2025. It was reconstructed in 2024.

What condition is Mountain Road over Cold Brook 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 November 2024.

How much traffic does Mountain Road over Cold Brook carry?

About 41 vehicles per day (2022 count), of which roughly 4% are trucks.

How long is Mountain Road over Cold Brook?

The structure is 34 ft (10.4 m) long with a longest span of 31 ft (9.4 m) and a deck 17 ft wide.

Who owns Mountain Road over Cold Brook?

It is owned by the City or Municipal Highway Agency.