US Bridges

Mill Road over Watnong Brook

Good

Morris County, New Jersey · 0.67MI SW US202&CR650 JCT · Structure no. 1400808

Built
2020
5 years old
Condition
Good
inspected June 2023
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
35 ft
1 main span
Daily traffic
3,248
2023 count
Owner
County
County Highway Agency

About this bridge

Mill Road over Watnong Brook is a prestressed concrete box beam or girders - multiple carrying Mill Road over Watnong Brook in Morris County, New Jersey. It was built in 2020, so it is 5 years old, younger than the New Jersey average of 58.5 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 3,248 vehicles a day, roughly 3% of them trucks, projected to reach 3,963 by 2043. The structure is 35 ft (10.7 m) long and 45 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

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CarriesMill Road
CrossesWatnong Brook
Location0.67MI SW US202&CR650 JCT
RouteCity Street 0
CountyMorris County
StateNew Jersey
Coordinates40.81904, -74.49375
Functional classUrban Collector

Condition and inspection

Good

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

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure9 ExcellentNo problems noted.
Substructure9 ExcellentNo problems noted.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJune 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation9: Superior to present desirable criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating93.6 US tons
Inventory rating72.1 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHL 93
Structure length35 ft (10.7 m)
Longest span30 ft (9.1 m)
Deck width45 ft (13.7 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,248 (2023)
Projected traffic3,963 by 2043
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty 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$970,000 (2019 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Mill Road over Watnong Brook built?

It was built in 2020, making it 5 years old in 2025.

What condition is Mill Road over Watnong 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 June 2023.

How much traffic does Mill Road over Watnong Brook carry?

About 3,248 vehicles per day (2023 count), of which roughly 3% are trucks.

How long is Mill Road over Watnong Brook?

The structure is 35 ft (10.7 m) long with a longest span of 30 ft (9.1 m) and a deck 45 ft wide.

Who owns Mill Road over Watnong Brook?

It is owned by the County Highway Agency.