US Bridges

US 4 Nh 11 over Ragged Mountain Brook

Good

Merrimack County, New Hampshire · 1.9 MI from Wilmot T.L. · Structure no. 000800710010400

Built
1959
66 years old
Condition
Good
inspected May 2024
Type
Frame
Concrete Continuous
Length
25 ft
2 main spans
Daily traffic
5,149
2023 count
Owner
State
State Highway Agency

About this bridge

US 4 Nh 11 over Ragged Mountain Brook is a concrete continuous frame carrying US 4 Nh 11 over Ragged Mountain Brook in Merrimack County, New Hampshire. It was built in 1959, so it is 66 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 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 5,149 vehicles a day, roughly 7% of them trucks, projected to reach 7,620 by 2043. The structure is 25 ft (7.6 m) long and 47 ft wide. If it were closed, the detour would be 39.8 mi (64 km).

Location

Open in Google Maps
CarriesUS 4 Nh 11
CrossesRagged Mountain Brook
Location1.9 MI from Wilmot T.L.
RouteU.S. Route 4
CountyMerrimack County
StateNew Hampshire
Coordinates43.43846, -71.847
Functional classRural Minor Arterial

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 inspectionMay 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating59.9 US tons
Inventory rating36 US tons

Structure

Structure typeFrame
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans2
Design loadHS 20
Structure length25 ft (7.6 m)
Longest span11 ft (3.4 m)
Deck width47 ft (14.2 m)
Roadway width44 ft (13.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic5,149 (2023)
Projected traffic7,620 by 2043
Trucks7%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed39.8 mi (64 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)
NavigationNo navigation control on waterway

Frequently asked questions

When was US 4 Nh 11 over Ragged Mountain Brook built?

It was built in 1959, making it 66 years old in 2025.

What condition is US 4 Nh 11 over Ragged Mountain Brook 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 May 2024.

How much traffic does US 4 Nh 11 over Ragged Mountain Brook carry?

About 5,149 vehicles per day (2023 count), of which roughly 7% are trucks.

How long is US 4 Nh 11 over Ragged Mountain Brook?

The structure is 25 ft (7.6 m) long with a longest span of 11 ft (3.4 m) and a deck 47 ft wide.

Who owns US 4 Nh 11 over Ragged Mountain Brook?

It is owned by the State Highway Agency.