US Bridges

NH109 over Nineteen Mile Bay

Good

Carroll County, New Hampshire · 5.0 MI SE Moultonboro Tl · Structure no. 025902010010000

Built
1993
32 years old
Condition
Good
inspected August 2024
Type
Frame
Concrete
Length
28 ft
1 main span
Daily traffic
2,518
2023 count
Owner
State
State Highway Agency

About this bridge

NH109 over Nineteen Mile Bay is a concrete frame carrying NH109 over Nineteen Mile Bay in Carroll County, New Hampshire. It was built in 1993, so it is 32 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 2,518 vehicles a day, roughly 4% of them trucks, projected to reach 3,726 by 2043. The structure is 28 ft (8.5 m) long and 40 ft wide. If it were closed, the detour would be 8.1 mi (13 km).

Location

Open in Google Maps
CarriesNH109
CrossesNineteen Mile Bay
Location5.0 MI SE Moultonboro Tl
RouteState Highway 109
CountyCarroll County
StateNew Hampshire
Coordinates43.64848, -71.2772
Functional classRural Major Collector

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.
Substructure8 Very GoodNo problems noted.
Channel and channel protection7 GoodSome minor problems.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating99 US tons
Inventory rating81 US tons

Structure

Structure typeFrame
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 25 or greater
Structure length28 ft (8.5 m)
Longest span20 ft (6.1 m)
Deck width40 ft (12.3 m)
Roadway width32 ft (9.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,518 (2023)
Projected traffic3,726 by 2043
Trucks4%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.1 mi (13 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
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 NH109 over Nineteen Mile Bay built?

It was built in 1993, making it 32 years old in 2025.

What condition is NH109 over Nineteen Mile Bay 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 2024.

How much traffic does NH109 over Nineteen Mile Bay carry?

About 2,518 vehicles per day (2023 count), of which roughly 4% are trucks.

How long is NH109 over Nineteen Mile Bay?

The structure is 28 ft (8.5 m) long with a longest span of 20 ft (6.1 m) and a deck 40 ft wide.

Who owns NH109 over Nineteen Mile Bay?

It is owned by the State Highway Agency.