US Bridges

Tremont Street over Contoocook River

Fair

Merrimack County, New Hampshire · Concord Tl · Structure no. 002601310003500

Built
1955
70 years old, rebuilt 1992
Condition
Fair
inspected July 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
269 ft
3 main spans
Daily traffic
6,767
2023 count
Owner
State
State Highway Agency

About this bridge

Tremont Street over Contoocook River is a steel continuous stringer/multi-beam or girder carrying Tremont Street over Contoocook River in Merrimack County, New Hampshire. It was built in 1955 and reconstructed in 1992, so it is 70 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 6 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 6,767 vehicles a day, roughly 5% of them trucks, projected to reach 10,015 by 2043. The structure is 269 ft (82 m) long and 40 ft wide.

CarriesTremont Street
CrossesContoocook River
LocationConcord Tl
RouteCity Street 0
Coordinates43.28506, -71.59673
Functional classUrban Minor Arterial

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum 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 rating82.3 US tons
Inventory rating49.3 US tons

Structure

MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 25 or greater
Structure length269 ft (82 m)
Longest span104 ft (31.7 m)
Deck width40 ft (12.2 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,767 (2023)
Projected traffic10,015 by 2043
Trucks5%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed—
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 Tremont Street over Contoocook River built?

It was built in 1955, making it 70 years old in 2025. It was reconstructed in 1992.

What condition is Tremont Street over Contoocook River 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 July 2023.

How much traffic does Tremont Street over Contoocook River carry?

About 6,767 vehicles per day (2023 count), of which roughly 5% are trucks.

How long is Tremont Street over Contoocook River?

The structure is 269 ft (82 m) long with a longest span of 104 ft (31.7 m) and a deck 40 ft wide.

Who owns Tremont Street over Contoocook River?

It is owned by the State Highway Agency.