US Bridges

CR 602 over Tributary of Back Brook

Fair

Hunterdon County, New Jersey · 1.74 MI East of Nj 31 · Structure no. 100E171

Built
1834
191 years old, rebuilt 2002
Condition
Fair
inspected May 2023
Type
Truss - Thru
Steel
Length
44 ft
1 main span
Daily traffic
1,850
2023 count
Owner
County
County Highway Agency

About this bridge

CR 602 over Tributary of Back Brook is a steel truss - thru carrying CR 602 over Tributary of Back Brook in Hunterdon County, New Jersey. It was built in 1834 and reconstructed in 2002, so it is 191 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 1,850 vehicles a day, roughly 3% of them trucks, projected to reach 2,220 by 2043. The structure is 44 ft (13.4 m) long and 25 ft wide. If it were closed, the detour would be 3.1 mi (5 km).

Location

Open in Google Maps
CarriesCR 602
CrossesTributary of Back Brook
Location1.74 MI East of Nj 31
RouteCounty Highway 602
CountyHunterdon County
StateNew Jersey
Coordinates40.42828, -74.83074
Functional classRural Major Collector

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
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 protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating30 US tons
Inventory rating18 US tons

Structure

Structure typeTruss - Thru
MaterialSteel
DeckCorrugated steel
Main spans1
Design loadHS 25 or greater
Structure length44 ft (13.4 m)
Longest span42 ft (12.8 m)
Deck width25 ft (7.7 m)
Roadway width25 ft (7.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,850 (2023)
Projected traffic2,220 by 2043
Trucks3%
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 statusEligible for the National Register of Historic Places
Work proposedOther structural work, including hydraulic replacements
Estimated improvement cost$150,000 (2023 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was CR 602 over Tributary of Back Brook built?

It was built in 1834, making it 191 years old in 2025. It was reconstructed in 2002.

What condition is CR 602 over Tributary of Back Brook 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 May 2023.

How much traffic does CR 602 over Tributary of Back Brook carry?

About 1,850 vehicles per day (2023 count), of which roughly 3% are trucks.

How long is CR 602 over Tributary of Back Brook?

The structure is 44 ft (13.4 m) long with a longest span of 42 ft (12.8 m) and a deck 25 ft wide.

Who owns CR 602 over Tributary of Back Brook?

It is owned by the County Highway Agency.