US Bridges

NH108 over CSX

Fair

Rockingham County, New Hampshire · Newmarket Tl · Structure no. 018301270008100

Built
1936
89 years old, rebuilt 1969
Condition
Fair
inspected July 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
151 ft
3 main spans
Daily traffic
16,562
2023 count
Owner
State
State Highway Agency

About this bridge

NH108 over CSX is a steel stringer/multi-beam or girder carrying NH108 over CSX in Rockingham County, New Hampshire. It was built in 1936 and reconstructed in 1969, so it is 89 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 16,562 vehicles a day, roughly 4% of them trucks, projected to reach 24,511 by 2043. The structure is 151 ft (46 m) long and 32 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesNH108
CrossesCSX
LocationNewmarket Tl
RouteState Highway 108
CountyRockingham County
StateNew Hampshire
Coordinates43.04997, -70.93398
Functional classUrban Collector

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure7 GoodSome minor problems.
Last inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry2: Basically intolerable, requiring high priority of replacement
Approach roadway alignment8: Equal to present desirable criteria
Operating rating50.4 US tons
Inventory rating36 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length151 ft (46 m)
Longest span54 ft (16.6 m)
Deck width32 ft (9.8 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic16,562 (2023)
Projected traffic24,511 by 2043
Trucks4%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesRailroad
Detour if closed3.1 mi (5 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)
NavigationNot applicable (no waterway)

Frequently asked questions

When was NH108 over CSX built?

It was built in 1936, making it 89 years old in 2025. It was reconstructed in 1969.

What condition is NH108 over CSX 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 2024.

How much traffic does NH108 over CSX carry?

About 16,562 vehicles per day (2023 count), of which roughly 4% are trucks.

How long is NH108 over CSX?

The structure is 151 ft (46 m) long with a longest span of 54 ft (16.6 m) and a deck 32 ft wide.

Who owns NH108 over CSX?

It is owned by the State Highway Agency.