US Bridges

Route 415 over Tahquamenon River

Fair

Luce County, Michigan · 2 Mi. N. Mc Millan · Structure no. 000000000005917

Built
1974
51 years old
Condition
Fair
inspected October 2024
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
87 ft
2 main spans
Daily traffic
40
2016 count
Owner
County
County Highway Agency

About this bridge

Route 415 over Tahquamenon River is a prestressed concrete box beam or girders - multiple carrying Route 415 over Tahquamenon River in Luce County, Michigan. It was built in 1974, so it is 51 years old, older 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 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 40 vehicles a day, projected to reach 200 by 2036. The structure is 87 ft (26.5 m) long and 31 ft wide. If it were closed, the detour would be 19.9 mi (32 km).

Location

Open in Google Maps
CarriesRoute 415
CrossesTahquamenon River
Location2 Mi. N. Mc Millan
RouteCounty Highway 4827
CountyLuce County
StateMichigan
Coordinates46.36332, -85.6857
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionOctober 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 geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating70.8 US tons
Inventory rating54.2 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans2
Design loadHS 20 + Mod
Structure length87 ft (26.5 m)
Longest span43 ft (13.1 m)
Deck width31 ft (9.3 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic40 (2016)
Projected traffic200 by 2036
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed19.9 mi (32 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 Route 415 over Tahquamenon River built?

It was built in 1974, making it 51 years old in 2025.

What condition is Route 415 over Tahquamenon 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 October 2024.

How much traffic does Route 415 over Tahquamenon River carry?

About 40 vehicles per day (2016 count).

How long is Route 415 over Tahquamenon River?

The structure is 87 ft (26.5 m) long with a longest span of 43 ft (13.1 m) and a deck 31 ft wide.

Who owns Route 415 over Tahquamenon River?

It is owned by the County Highway Agency.