US Bridges

NH175 over Eastman Brook

Good

Grafton County, New Hampshire · .2 MI from Thornton Tl · Structure no. 028402050007800

Built
1973
52 years old, rebuilt 2009
Condition
Good
inspected May 2024
Type
Frame
Concrete
Length
57 ft
1 main span
Daily traffic
183
2023 count
Owner
State
State Highway Agency

About this bridge

NH175 over Eastman Brook is a concrete frame carrying NH175 over Eastman Brook in Grafton County, New Hampshire. It was built in 1973 and reconstructed in 2009, so it is 52 years old, younger 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 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 183 vehicles a day, roughly 10% of them trucks, projected to reach 270 by 2043. The structure is 57 ft (17.4 m) long and 31 ft wide. If it were closed, the detour would be 8.7 mi (14 km).

Location

Open in Google Maps
CarriesNH175
CrossesEastman Brook
Location.2 MI from Thornton Tl
RouteState Highway 175
CountyGrafton County
StateNew Hampshire
Coordinates43.96884, -71.67358
Functional classRural Minor Collector

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.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating49.7 US tons
Inventory rating29.7 US tons

Structure

Structure typeFrame
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length57 ft (17.4 m)
Longest span50 ft (15.2 m)
Deck width31 ft (9.4 m)
Roadway width27 ft (8.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic183 (2023)
Projected traffic270 by 2043
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.7 mi (14 km)
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 NH175 over Eastman Brook built?

It was built in 1973, making it 52 years old in 2025. It was reconstructed in 2009.

What condition is NH175 over Eastman Brook 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 May 2024.

How much traffic does NH175 over Eastman Brook carry?

About 183 vehicles per day (2023 count), of which roughly 10% are trucks.

How long is NH175 over Eastman Brook?

The structure is 57 ft (17.4 m) long with a longest span of 50 ft (15.2 m) and a deck 31 ft wide.

Who owns NH175 over Eastman Brook?

It is owned by the State Highway Agency.