US Bridges

Nh 9 NH108 NB over Cocheco River

Fair

Strafford County, New Hampshire · NB 16 & EB 4 · Structure no. 006501340012200

Built
1977
48 years old
Condition
Fair
inspected September 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
101 ft
1 main span
Daily traffic
12,115
2023 count
Owner
City
City or Municipal Highway Agency

About this bridge

Nh 9 NH108 NB over Cocheco River is a steel stringer/multi-beam or girder carrying Nh 9 NH108 NB over Cocheco River in Strafford County, New Hampshire. It was built in 1977, so it is 48 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 12,115 vehicles a day, roughly 8% of them trucks, projected to reach 17,930 by 2043. The structure is 101 ft (30.8 m) long and 59 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

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CarriesNh 9 NH108 NB
CrossesCocheco River
LocationNB 16 & EB 4
RouteCity Street 16
CountyStrafford County
StateNew Hampshire
Coordinates43.19512, -70.87269
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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry9: Superior to present desirable criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating50 US tons
Inventory rating36 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length101 ft (30.8 m)
Longest span96 ft (29.3 m)
Deck width59 ft (17.9 m)
Roadway width44 ft (13.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic12,115 (2023)
Projected traffic17,930 by 2043
Trucks8%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal 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 Nh 9 NH108 NB over Cocheco River built?

It was built in 1977, making it 48 years old in 2025.

What condition is Nh 9 NH108 NB over Cocheco 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 September 2024.

How much traffic does Nh 9 NH108 NB over Cocheco River carry?

About 12,115 vehicles per day (2023 count), of which roughly 8% are trucks.

How long is Nh 9 NH108 NB over Cocheco River?

The structure is 101 ft (30.8 m) long with a longest span of 96 ft (29.3 m) and a deck 59 ft wide.

Who owns Nh 9 NH108 NB over Cocheco River?

It is owned by the City or Municipal Highway Agency.