US Bridges

NH104 over Pemigewasset River

Fair

Grafton County, New Hampshire · New Hampton Tl · Structure no. 003201830008700

Built
1987
38 years old
Condition
Fair
inspected July 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
411 ft
3 main spans
Daily traffic
9,297
2023 count
Owner
State
State Highway Agency

About this bridge

NH104 over Pemigewasset River is a steel continuous stringer/multi-beam or girder carrying NH104 over Pemigewasset River in Grafton County, New Hampshire. It was built in 1987, so it is 38 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 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 9,297 vehicles a day, roughly 7% of them trucks, projected to reach 13,759 by 2043. The structure is 411 ft (125.3 m) long and 47 ft wide. If it were closed, the detour would be 9.9 mi (16 km).

Location

Open in Google Maps
CarriesNH104
CrossesPemigewasset River
LocationNew Hampton Tl
RouteState Highway 104
CountyGrafton County
StateNew Hampshire
Coordinates43.60656, -71.66268
Functional classRural 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.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourCountermeasures installed to correct a previously existing problem
Structural evaluation7: Better than 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 rating65.7 US tons
Inventory rating39.4 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20 + Mod
Structure length411 ft (125.3 m)
Longest span155 ft (47.2 m)
Deck width47 ft (14.2 m)
Roadway width43 ft (13.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic9,297 (2023)
Projected traffic13,759 by 2043
Trucks7%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed9.9 mi (16 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
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 NH104 over Pemigewasset River built?

It was built in 1987, making it 38 years old in 2025.

What condition is NH104 over Pemigewasset 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 NH104 over Pemigewasset River carry?

About 9,297 vehicles per day (2023 count), of which roughly 7% are trucks.

How long is NH104 over Pemigewasset River?

The structure is 411 ft (125.3 m) long with a longest span of 155 ft (47.2 m) and a deck 47 ft wide.

Who owns NH104 over Pemigewasset River?

It is owned by the State Highway Agency.