US Bridges

CR 670 over Mill Brook

Fair

Morris County, New Jersey · 0.23 M So Nj RTE 10 · Structure no. 1400772

Built
1970
55 years old
Condition
Fair
inspected June 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
31 ft
1 main span
Daily traffic
6,236
2023 count
Owner
County
County Highway Agency

About this bridge

CR 670 over Mill Brook is a steel stringer/multi-beam or girder carrying CR 670 over Mill Brook in Morris 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 6,236 vehicles a day, roughly 4% of them trucks, projected to reach 7,609 by 2043. The structure is 31 ft (9.4 m) long and 56 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesCR 670
CrossesMill Brook
Location0.23 M So Nj RTE 10
RouteCounty Highway 670
CountyMorris County
StateNew Jersey
Coordinates40.85369, -74.57742
Functional classUrban Minor 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.
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 evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry9: Superior to present desirable criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating110.1 US tons
Inventory rating61.9 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckCorrugated steel
Main spans1
Design loadUnknown
Structure length31 ft (9.4 m)
Longest span27 ft (8.2 m)
Deck width56 ft (17.1 m)
Roadway width46 ft (14 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,236 (2023)
Projected traffic7,609 by 2043
Trucks4%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed3.7 mi (6 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedOther structural work, including hydraulic replacements
Estimated improvement cost$272,000 (2023 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was CR 670 over Mill Brook built?

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

What condition is CR 670 over Mill 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 June 2023.

How much traffic does CR 670 over Mill Brook carry?

About 6,236 vehicles per day (2023 count), of which roughly 4% are trucks.

How long is CR 670 over Mill Brook?

The structure is 31 ft (9.4 m) long with a longest span of 27 ft (8.2 m) and a deck 56 ft wide.

Who owns CR 670 over Mill Brook?

It is owned by the County Highway Agency.