US Bridges

County Route 518 over Stony Brook

Good

Mercer County, New Jersey · 0.21 Mile E of Rt 31 · Structure no. 1102302

Built
1959
66 years old, rebuilt 2014
Condition
Good
inspected February 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
121 ft
2 main spans
Daily traffic
5,445
2023 count
Owner
County
County Highway Agency

About this bridge

County Route 518 over Stony Brook is a steel continuous stringer/multi-beam or girder carrying County Route 518 over Stony Brook in Mercer County, New Jersey. It was built in 1959 and reconstructed in 2014, so it is 66 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 good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 5,445 vehicles a day, roughly 4% of them trucks, projected to reach 6,640 by 2043. The structure is 121 ft (36.9 m) long and 44 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesCounty Route 518
CrossesStony Brook
Location0.21 Mile E of Rt 31
RouteCounty Highway 518
CountyMercer County
StateNew Jersey
Coordinates40.38368, -74.81505
Functional classRural Minor Arterial

Condition and inspection

Good

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

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure8 Very GoodNo problems noted.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionFebruary 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourCountermeasures installed to correct a previously existing problem
Structural evaluation7: Better than present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating110.1 US tons
Inventory rating110.1 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans2
Design loadHS 25 or greater
Structure length121 ft (36.9 m)
Longest span59 ft (18 m)
Deck width44 ft (13.4 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic5,445 (2023)
Projected traffic6,640 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

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was County Route 518 over Stony Brook built?

It was built in 1959, making it 66 years old in 2025. It was reconstructed in 2014.

What condition is County Route 518 over Stony 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 February 2023.

How much traffic does County Route 518 over Stony Brook carry?

About 5,445 vehicles per day (2023 count), of which roughly 4% are trucks.

How long is County Route 518 over Stony Brook?

The structure is 121 ft (36.9 m) long with a longest span of 59 ft (18 m) and a deck 44 ft wide.

Who owns County Route 518 over Stony Brook?

It is owned by the County Highway Agency.