US Bridges

Fourth Street over Cocheco River

Good

Strafford County, New Hampshire · Downtown Dover · Structure no. 006501230012600

Built
1978
47 years old
Condition
Good
inspected September 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
179 ft
2 main spans
Daily traffic
2,189
2023 count
Owner
City
City or Municipal Highway Agency

About this bridge

Fourth Street over Cocheco River is a steel continuous stringer/multi-beam or girder carrying Fourth Street over Cocheco River in Strafford County, New Hampshire. It was built in 1978, so it is 47 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 2,189 vehicles a day, roughly 3% of them trucks, projected to reach 3,239 by 2043. The structure is 179 ft (54.6 m) long and 33 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

CarriesFourth Street
CrossesCocheco River
LocationDowntown Dover
RouteCity Street 0
Coordinates43.19988, -70.88202
Functional classUrban Local

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
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
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation7: Better than present minimum criteria
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating49.9 US tons
Inventory rating36 US tons

Structure

MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans2
Design loadHS 20
Structure length179 ft (54.6 m)
Longest span88 ft (26.8 m)
Deck width33 ft (10.2 m)
Roadway width26 ft (7.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,189 (2023)
Projected traffic3,239 by 2043
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed3.1 mi (5 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 Fourth Street over Cocheco River built?

It was built in 1978, making it 47 years old in 2025.

What condition is Fourth Street over Cocheco River 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 September 2024.

How much traffic does Fourth Street over Cocheco River carry?

About 2,189 vehicles per day (2023 count), of which roughly 3% are trucks.

How long is Fourth Street over Cocheco River?

The structure is 179 ft (54.6 m) long with a longest span of 88 ft (26.8 m) and a deck 33 ft wide.

Who owns Fourth Street over Cocheco River?

It is owned by the City or Municipal Highway Agency.