US Bridges

US 46 over Mill Race

Fair

Morris County, New Jersey · 0.21 MI E of CR 604 · Structure no. 1407150

Built
1921
104 years old, rebuilt 1952
Condition
Fair
inspected April 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
26 ft
1 main span
Daily traffic
13,124
2023 count
Owner
State
State Highway Agency

About this bridge

US 46 over Mill Race is a steel stringer/multi-beam or girder carrying US 46 over Mill Race in Morris County, New Jersey. It was built in 1921 and reconstructed in 1952, so it is 104 years old, older than the New Jersey average of 58.5 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 13,124 vehicles a day, roughly 4% of them trucks, projected to reach 16,013 by 2043. The structure is 26 ft (7.9 m) long and 40 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesUS 46
CrossesMill Race
Location0.21 MI E of CR 604
RouteU.S. Route 46
CountyMorris County
StateNew Jersey
Coordinates40.84837, -74.82067
Functional classUrban Other Principal 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 protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionApril 2023
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 adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating65 US tons
Inventory rating39 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadUnknown
Structure length26 ft (7.9 m)
Longest span22 ft (6.7 m)
Deck width40 ft (12.2 m)
Roadway width30 ft (9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic13,124 (2023)
Projected traffic16,013 by 2043
Trucks4%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedWidening of existing bridge without deck rehabilitation
Estimated improvement cost$222,000 (2023 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was US 46 over Mill Race built?

It was built in 1921, making it 104 years old in 2025. It was reconstructed in 1952.

What condition is US 46 over Mill Race 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 April 2023.

How much traffic does US 46 over Mill Race carry?

About 13,124 vehicles per day (2023 count), of which roughly 4% are trucks.

How long is US 46 over Mill Race?

The structure is 26 ft (7.9 m) long with a longest span of 22 ft (6.7 m) and a deck 40 ft wide.

Who owns US 46 over Mill Race?

It is owned by the State Highway Agency.