US Bridges

Nj 27 over Millstone River

Fair

Mercer County, New Jersey · 3.08 MI N US 206 JCT · Structure no. 1105152

Built
1970
55 years old
Condition
Fair
inspected June 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
184 ft
2 main spans
Daily traffic
12,700
2023 count
Owner
State
State Highway Agency

About this bridge

Nj 27 over Millstone River is a steel stringer/multi-beam or girder carrying Nj 27 over Millstone River in Mercer County, New Jersey. It was built in 1970, so it is 55 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 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 12,700 vehicles a day, roughly 4% of them trucks, projected to reach 15,240 by 2043. The structure is 184 ft (56.1 m) long and 64 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesNj 27
CrossesMillstone River
Location3.08 MI N US 206 JCT
RouteState Highway 27
CountyMercer County
StateNew Jersey
Coordinates40.37408, -74.62028
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.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJune 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment7: Better than present minimum criteria
Operating rating110.1 US tons
Inventory rating60 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans2
Design loadHS 20 + Mod
Structure length184 ft (56.1 m)
Longest span100 ft (30.5 m)
Deck width64 ft (19.6 m)
Roadway width50 ft (15.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic12,700 (2023)
Projected traffic15,240 by 2043
Trucks4%
Lanes on structure3
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed3.1 mi (5 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedOther structural work, including hydraulic replacements
Estimated improvement cost$480,000 (2023 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Nj 27 over Millstone River built?

It was built in 1970, making it 55 years old in 2025.

What condition is Nj 27 over Millstone River 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 June 2023.

How much traffic does Nj 27 over Millstone River carry?

About 12,700 vehicles per day (2023 count), of which roughly 4% are trucks.

How long is Nj 27 over Millstone River?

The structure is 184 ft (56.1 m) long with a longest span of 100 ft (30.5 m) and a deck 64 ft wide.

Who owns Nj 27 over Millstone River?

It is owned by the State Highway Agency.