US Bridges

Turtle RD over Au Gres River

Fair

Iosco County, Michigan · 2.125 MI E of M-65 · Structure no. 000000000004131

Built
2003
22 years old
Condition
Fair
inspected June 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
105 ft
1 main span
Daily traffic
780
2006 count
Owner
County
County Highway Agency

About this bridge

Turtle RD over Au Gres River is a prestressed concrete stringer/multi-beam or girder carrying Turtle RD over Au Gres River in Iosco County, Michigan. It was built in 2003, so it is 22 years old, younger than the Michigan average of 48.3 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 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 780 vehicles a day, roughly 10% of them trucks, projected to reach 1,400 by 2026. The structure is 105 ft (32 m) long and 34 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

CarriesTurtle RD
CrossesAu Gres River
Location2.125 MI E of M-65
RouteCounty Highway 3508
Coordinates44.19068, -83.75977
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
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment9: Superior to present desirable criteria
Operating rating79.3 US tons
Inventory rating37.8 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length105 ft (32 m)
Longest span101 ft (30.8 m)
Deck width34 ft (10.3 m)
Roadway width31 ft (9.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic780 (2006)
Projected traffic1,400 by 2026
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 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 Turtle RD over Au Gres River built?

It was built in 2003, making it 22 years old in 2025.

What condition is Turtle RD over Au Gres River 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 2024.

How much traffic does Turtle RD over Au Gres River carry?

About 780 vehicles per day (2006 count), of which roughly 10% are trucks.

How long is Turtle RD over Au Gres River?

The structure is 105 ft (32 m) long with a longest span of 101 ft (30.8 m) and a deck 34 ft wide.

Who owns Turtle RD over Au Gres River?

It is owned by the County Highway Agency.