US Bridges

Riverdale Road over Newfound River

Good

Grafton County, New Hampshire · 0.02 MI West of Nh 3A · Structure no. 003201000009500

Built
1949
76 years old
Condition
Good
inspected August 2023
Type
Slab
Concrete
Length
81 ft
3 main spans
Daily traffic
103
2023 count
Owner
City
City or Municipal Highway Agency

About this bridge

Riverdale Road over Newfound River is a concrete slab carrying Riverdale Road over Newfound River in Grafton County, New Hampshire. It was built in 1949, so it is 76 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 103 vehicles a day, projected to reach 152 by 2043. The structure is 81 ft (24.7 m) long and 21 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

Location

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CarriesRiverdale Road
CrossesNewfound River
Location0.02 MI West of Nh 3A
CountyGrafton County
StateNew Hampshire
Coordinates43.61344, -71.74156
Functional classRural 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 protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating26 US tons
Inventory rating16 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans3
Design loadH 10
Structure length81 ft (24.7 m)
Longest span32 ft (9.8 m)
Deck width21 ft (6.4 m)
Roadway width18 ft (5.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic103 (2023)
Projected traffic152 by 2043
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.8 mi (159 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 Riverdale Road over Newfound River built?

It was built in 1949, making it 76 years old in 2025.

What condition is Riverdale Road over Newfound 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 August 2023.

How much traffic does Riverdale Road over Newfound River carry?

About 103 vehicles per day (2023 count).

How long is Riverdale Road over Newfound River?

The structure is 81 ft (24.7 m) long with a longest span of 32 ft (9.8 m) and a deck 21 ft wide.

Who owns Riverdale Road over Newfound River?

It is owned by the City or Municipal Highway Agency.