US Bridges

US-31|HONOR HWY over Platte River

Fair

Benzie County, Michigan · 0.8 MI W of Honor · Structure no. 000000000000756

Built
1927
98 years old, rebuilt 1999
Condition
Fair
inspected July 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
35 ft
1 main span
Daily traffic
8,172
2022 count
Owner
State
State Highway Agency

About this bridge

US-31|HONOR HWY over Platte River is a steel stringer/multi-beam or girder carrying US-31|HONOR HWY over Platte River in Benzie County, Michigan. It was built in 1927 and reconstructed in 1999, so it is 98 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 8,172 vehicles a day, roughly 5% of them trucks, projected to reach 2,022 by 8172. The structure is 35 ft (10.7 m) long and 37 ft wide. If it were closed, the detour would be 9.9 mi (16 km).

Location

Open in Google Maps
CarriesUS-31|HONOR HWY
CrossesPlatte River
Location0.8 MI W of Honor
RouteU.S. Route 31
CountyBenzie County
StateMichigan
Coordinates44.66785, -86.03487
Functional classRural Principal Arterial - Other

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJuly 2024
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 geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy2: Basically intolerable, requiring high priority of replacement
Approach roadway alignment6: Equal to present minimum criteria
Operating rating107.1 US tons
Inventory rating65.4 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadHS 25 or greater
Structure length35 ft (10.7 m)
Longest span33 ft (10 m)
Deck width37 ft (11.2 m)
Roadway width34 ft (10.5 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic8,172 (2022)
Projected traffic2,022 by 8172
Trucks5%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed9.9 mi (16 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState 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 US-31|HONOR HWY over Platte River built?

It was built in 1927, making it 98 years old in 2025. It was reconstructed in 1999.

What condition is US-31|HONOR HWY over Platte 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 July 2024.

How much traffic does US-31|HONOR HWY over Platte River carry?

About 8,172 vehicles per day (2022 count), of which roughly 5% are trucks.

How long is US-31|HONOR HWY over Platte River?

The structure is 35 ft (10.7 m) long with a longest span of 33 ft (10 m) and a deck 37 ft wide.

Who owns US-31|HONOR HWY over Platte River?

It is owned by the State Highway Agency.