US Bridges

Nh 11 over Bk Bay LA Winnipesaukee

Fair

Belknap County, New Hampshire · 0.25 MI N Alton Bay · Structure no. 000601570019300

Built
1942
83 years old
Condition
Fair
inspected May 2024
Type
Arch - Deck
Masonry
Length
45 ft
1 main span
Daily traffic
6,310
2023 count
Owner
State
State Highway Agency

About this bridge

Nh 11 over Bk Bay LA Winnipesaukee is a masonry arch - deck carrying Nh 11 over Bk Bay LA Winnipesaukee in Belknap County, New Hampshire. It was built in 1942, so it is 83 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 5 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 6,310 vehicles a day, roughly 7% of them trucks, projected to reach 9,338 by 2043. The structure is 45 ft (13.7 m) long and 40 ft wide. If it were closed, the detour would be 11.2 mi (18 km).

Location

Open in Google Maps
CarriesNh 11
CrossesBk Bay LA Winnipesaukee
Location0.25 MI N Alton Bay
RouteState Highway 11
CountyBelknap County
StateNew Hampshire
Coordinates43.47665, -71.24009
Functional classUrban 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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMay 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating44.5 US tons
Inventory rating26.6 US tons

Structure

Structure typeArch - Deck
MaterialMasonry
DeckNot applicable
Main spans1
Design loadH 15
Structure length45 ft (13.7 m)
Longest span27 ft (8.2 m)
Deck width40 ft (12.2 m)
Roadway width28 ft (8.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,310 (2023)
Projected traffic9,338 by 2043
Trucks7%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed11.2 mi (18 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 Nh 11 over Bk Bay LA Winnipesaukee built?

It was built in 1942, making it 83 years old in 2025.

What condition is Nh 11 over Bk Bay LA Winnipesaukee 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 May 2024.

How much traffic does Nh 11 over Bk Bay LA Winnipesaukee carry?

About 6,310 vehicles per day (2023 count), of which roughly 7% are trucks.

How long is Nh 11 over Bk Bay LA Winnipesaukee?

The structure is 45 ft (13.7 m) long with a longest span of 27 ft (8.2 m) and a deck 40 ft wide.

Who owns Nh 11 over Bk Bay LA Winnipesaukee?

It is owned by the State Highway Agency.