US Bridges

Mill Brook Road over Mill Brook

Good

Grafton County, New Hampshire · 20 West of Br. #165/151 · Structure no. 025401670015100

Built
2019
6 years old
Condition
Good
inspected September 2023
Type
Culvert
Steel
Length
22 ft
3 main spans
Daily traffic
96
2023 count
Owner
City
City or Municipal Highway Agency

About this bridge

Mill Brook Road over Mill Brook is a steel culvert carrying Mill Brook Road over Mill Brook in Grafton County, New Hampshire. It was built in 2019, so it is 6 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 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 96 vehicles a day, roughly 4% of them trucks, projected to reach 142 by 2043. The structure is 22 ft (6.7 m) long. If it were closed, the detour would be 95.1 mi (153 km).

Location

Open in Google Maps
CarriesMill Brook Road
CrossesMill Brook
Location20 West of Br. #165/151
CountyGrafton County
StateNew Hampshire
Coordinates43.93089, -71.61421
Functional classRural Local

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Channel and channel protection7 GoodSome minor problems.
Culvert8 Very GoodNo problems noted.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation8: Equal to present desirable criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating99 US tons
Inventory rating99 US tons

Structure

Structure typeCulvert
MaterialSteel
DeckNot applicable
Main spans3
Design loadUnknown
Structure length22 ft (6.7 m)
Longest span6 ft (1.8 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 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 closed95.1 mi (153 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 Mill Brook Road over Mill Brook built?

It was built in 2019, making it 6 years old in 2025.

What condition is Mill Brook Road over Mill Brook 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 September 2023.

How much traffic does Mill Brook Road over Mill Brook carry?

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

How long is Mill Brook Road over Mill Brook?

The structure is 22 ft (6.7 m) long with a longest span of 6 ft (1.8 m).

Who owns Mill Brook Road over Mill Brook?

It is owned by the City or Municipal Highway Agency.