US Bridges

Aat Road over Mulligan Creek

Good

Marquette County, Michigan · 8 MI W of HWY 510 on Att · Structure no. 000000000006564

Built
2013
12 years old
Condition
Good
inspected October 2023
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
50 ft
1 main span
Daily traffic
50
2012 count
Owner
County
County Highway Agency

About this bridge

Aat Road over Mulligan Creek is a prestressed concrete box beam or girders - multiple carrying Aat Road over Mulligan Creek in Marquette County, Michigan. It was built in 2013, so it is 12 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 50 vehicles a day, projected to reach 65 by 2032. The structure is 50 ft (15.2 m) long and 25 ft wide. If it were closed, the detour would be 124.3 mi (200 km).

Location

Open in Google Maps
CarriesAat Road
CrossesMulligan Creek
Location8 MI W of HWY 510 on Att
RouteCounty Highway 0
CountyMarquette County
StateMichigan
Coordinates46.64021, -87.78707
Functional classRural Local

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 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating78.2 US tons
Inventory rating47.7 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadGreater than HL 93
Structure length50 ft (15.2 m)
Longest span48 ft (14.6 m)
Deck width25 ft (7.6 m)
Roadway width25 ft (7.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic50 (2012)
Projected traffic65 by 2032
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed124.3 mi (200 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 Aat Road over Mulligan Creek built?

It was built in 2013, making it 12 years old in 2025.

What condition is Aat Road over Mulligan 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 2023.

How much traffic does Aat Road over Mulligan Creek carry?

About 50 vehicles per day (2012 count).

How long is Aat Road over Mulligan Creek?

The structure is 50 ft (15.2 m) long with a longest span of 48 ft (14.6 m) and a deck 25 ft wide.

Who owns Aat Road over Mulligan Creek?

It is owned by the County Highway Agency.