US Bridges

NH101 over Tower Hill Road

Fair

Rockingham County, New Hampshire · 2.6 MI JCT Rt 28 · Structure no. 001300880016200

Built
1964
61 years old
Condition
Fair
inspected March 2023
Type
Culvert
Concrete
Length
27 ft
1 main span
Daily traffic
52,392
2023 count
Owner
State
State Highway Agency

About this bridge

NH101 over Tower Hill Road is a concrete culvert carrying NH101 over Tower Hill Road in Rockingham County, New Hampshire. It was built in 1964, so it is 61 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 52,392 vehicles a day, roughly 7% of them trucks, projected to reach 77,540 by 2043. The structure is 27 ft (8.2 m) long and 130 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesNH101
CrossesTower Hill Road
Location2.6 MI JCT Rt 28
RouteState Highway 101
CountyRockingham County
StateNew Hampshire
Coordinates43.02903, -71.35782
Functional classRural Principal Arterial - Other

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMarch 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating72.4 US tons
Inventory rating43.4 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans1
Design loadHS 20
Structure length27 ft (8.2 m)
Longest span23 ft (7 m)
Deck width130 ft (39.6 m)
Roadway width111 ft (33.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic52,392 (2023)
Projected traffic77,540 by 2043
Trucks7%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemYes

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)
NavigationNot applicable (no waterway)

Frequently asked questions

When was NH101 over Tower Hill Road built?

It was built in 1964, making it 61 years old in 2025.

What condition is NH101 over Tower Hill Road 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 March 2023.

How much traffic does NH101 over Tower Hill Road carry?

About 52,392 vehicles per day (2023 count), of which roughly 7% are trucks.

How long is NH101 over Tower Hill Road?

The structure is 27 ft (8.2 m) long with a longest span of 23 ft (7 m) and a deck 130 ft wide.

Who owns NH101 over Tower Hill Road?

It is owned by the State Highway Agency.