US Bridges

Nh 13 over Whittle Brook

Fair

Hillsborough County, New Hampshire · 1.6 MI NE New Boston Tl · Structure no. 009500840010400

Built
1932
93 years old
Condition
Fair
inspected July 2023
Type
Frame
Concrete
Length
24 ft
1 main span
Daily traffic
4,360
2023 count
Owner
City
City or Municipal Highway Agency

About this bridge

Nh 13 over Whittle Brook is a concrete frame carrying Nh 13 over Whittle Brook in Hillsborough County, New Hampshire. It was built in 1932, so it is 93 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 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 4,360 vehicles a day, roughly 4% of them trucks, projected to reach 6,452 by 2043. The structure is 24 ft (7.3 m) long and 29 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesNh 13
CrossesWhittle Brook
Location1.6 MI NE New Boston Tl
RouteState Highway 13
CountyHillsborough County
StateNew Hampshire
Coordinates43.016, -71.60002
Functional classRural 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.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating44.6 US tons
Inventory rating32.4 US tons

Structure

Structure typeFrame
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadUnknown
Structure length24 ft (7.3 m)
Longest span20 ft (6.1 m)
Deck width29 ft (8.8 m)
Roadway width25 ft (7.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,360 (2023)
Projected traffic6,452 by 2043
Trucks4%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed3.7 mi (6 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 13 over Whittle Brook built?

It was built in 1932, making it 93 years old in 2025.

What condition is Nh 13 over Whittle Brook 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 July 2023.

How much traffic does Nh 13 over Whittle Brook carry?

About 4,360 vehicles per day (2023 count), of which roughly 4% are trucks.

How long is Nh 13 over Whittle Brook?

The structure is 24 ft (7.3 m) long with a longest span of 20 ft (6.1 m) and a deck 29 ft wide.

Who owns Nh 13 over Whittle Brook?

It is owned by the City or Municipal Highway Agency.