US Bridges

Millbrook Road over Mill Brook

Fair

Grafton County, New Hampshire · 0.9MI. Orange Tl · Structure no. 009901610013500

Built
2005
20 years old
Condition
Fair
inspected August 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
42 ft
1 main span
Daily traffic
96
2023 count
Owner
City
City or Municipal Highway Agency

About this bridge

Millbrook Road over Mill Brook is a steel stringer/multi-beam or girder carrying Millbrook Road over Mill Brook in Grafton County, New Hampshire. It was built in 2005, so it is 20 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 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 96 vehicles a day, roughly 4% of them trucks, projected to reach 142 by 2043. The structure is 42 ft (12.7 m) long and 18 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesMillbrook Road
CrossesMill Brook
Location0.9MI. Orange Tl
CountyGrafton County
StateNew Hampshire
Coordinates43.6009, -71.94009
Functional classRural Local

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.
Substructure8 Very GoodNo problems noted.
Channel and channel protection4 PoorAdvanced section loss, deterioration, spalling or scour.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment6: Equal to present minimum criteria
Operating rating24.9 US tons
Inventory rating15 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, precast panels
Main spans1
Design loadUnknown
Structure length42 ft (12.7 m)
Longest span39 ft (11.8 m)
Deck width18 ft (5.4 m)
Roadway width16 ft (4.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic96 (2023)
Projected traffic142 by 2043
Trucks4%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.1 mi (5 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal 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 Millbrook Road over Mill Brook built?

It was built in 2005, making it 20 years old in 2025.

What condition is Millbrook Road over Mill 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 August 2023.

How much traffic does Millbrook Road over Mill Brook carry?

About 96 vehicles per day (2023 count), of which roughly 4% are trucks.

How long is Millbrook Road over Mill Brook?

The structure is 42 ft (12.7 m) long with a longest span of 39 ft (11.8 m) and a deck 18 ft wide.

Who owns Millbrook Road over Mill Brook?

It is owned by the City or Municipal Highway Agency.