US Bridges

County Road 550 over Harlow Creek

Good

Marquette County, Michigan · 6 Miles No Marquette · Structure no. 000000000006559

Built
2014
11 years old
Condition
Good
inspected October 2024
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
60 ft
1 main span
Daily traffic
1,400
2013 count
Owner
County
County Highway Agency

About this bridge

County Road 550 over Harlow Creek is a prestressed concrete box beam or girders - multiple carrying County Road 550 over Harlow Creek in Marquette County, Michigan. It was built in 2014, so it is 11 years old, younger than the Michigan average of 48.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 1,400 vehicles a day, roughly 11% of them trucks, projected to reach 1,450 by 2033. The structure is 60 ft (18.3 m) long and 44 ft wide. If it were closed, the detour would be 29.8 mi (48 km).

CarriesCounty Road 550
CrossesHarlow Creek
Location6 Miles No Marquette
RouteCounty Highway 5283
Coordinates46.6326, -87.47528
Functional classRural Major Collector

Condition and inspection

Good

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

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating66 US tons
Inventory rating51 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20 + Mod
Structure length60 ft (18.3 m)
Longest span59 ft (17.9 m)
Deck width44 ft (13.4 m)
Roadway width41 ft (12.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,400 (2013)
Projected traffic1,450 by 2033
Trucks11%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed29.8 mi (48 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 Road 550 over Harlow Creek built?

It was built in 2014, making it 11 years old in 2025.

What condition is County Road 550 over Harlow Creek 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 October 2024.

How much traffic does County Road 550 over Harlow Creek carry?

About 1,400 vehicles per day (2013 count), of which roughly 11% are trucks.

How long is County Road 550 over Harlow Creek?

The structure is 60 ft (18.3 m) long with a longest span of 59 ft (17.9 m) and a deck 44 ft wide.

Who owns County Road 550 over Harlow Creek?

It is owned by the County Highway Agency.