US Bridges

Nh 16 SP Tpk NB over NH108 Csx(abd)

Poor

Strafford County, New Hampshire · 0.2 MI from Jct. RTE 16 · Structure no. 006501320010200

Built
1957
68 years old, rebuilt 1999
Condition
Poor
inspected October 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
206 ft
4 main spans
Daily traffic
22,163
2023 count
Owner
Toll Authority
State Toll Authority

About this bridge

Nh 16 SP Tpk NB over NH108 Csx(abd) is a steel continuous stringer/multi-beam or girder carrying Nh 16 SP Tpk NB over NH108 Csx(abd) in Strafford County, New Hampshire. It was built in 1957 and reconstructed in 1999, so it is 68 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 poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 22,163 vehicles a day, roughly 8% of them trucks, projected to reach 32,801 by 2043. The structure is 206 ft (62.8 m) long and 48 ft wide. If it were closed, the detour would be 5 mi (8 km).

CarriesNh 16 SP Tpk NB
CrossesNH108 Csx(abd)
Location0.2 MI from Jct. RTE 16
RouteState Highway 16
Coordinates43.18154, -70.87684
Functional classUrban Principal Arterial - Other Freeway or Expressway

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionOctober 2024
Inspection intervalevery 8 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 geometry8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating48.6 US tons
Inventory rating29.2 US tons

Structure

MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length206 ft (62.8 m)
Longest span62 ft (18.9 m)
Deck width48 ft (14.6 m)
Roadway width42 ft (12.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic22,163 (2023)
Projected traffic32,801 by 2043
Trucks8%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed5 mi (8 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkNon-Interstate STRAHNET route

Ownership and planned work

OwnerState Toll Authority
Maintained byState Toll Authority
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 Nh 16 SP Tpk NB over NH108 Csx(abd) built?

It was built in 1957, making it 68 years old in 2025. It was reconstructed in 1999.

What condition is Nh 16 SP Tpk NB over NH108 Csx(abd) in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in October 2024.

How much traffic does Nh 16 SP Tpk NB over NH108 Csx(abd) carry?

About 22,163 vehicles per day (2023 count), of which roughly 8% are trucks.

How long is Nh 16 SP Tpk NB over NH108 Csx(abd)?

The structure is 206 ft (62.8 m) long with a longest span of 62 ft (18.9 m) and a deck 48 ft wide.

Who owns Nh 16 SP Tpk NB over NH108 Csx(abd)?

It is owned by the State Toll Authority.