US Bridges

Fw Road over Black River

Fair

Marquette County, Michigan · 0.2 MI S of 478 HWY · Structure no. 000000000006585

Built
1934
91 years old
Condition
Fair
inspected October 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
38 ft
1 main span
Daily traffic
10
1994 count
Owner
County
County Highway Agency

About this bridge

Fw Road over Black River is a steel stringer/multi-beam or girder carrying Fw Road over Black River in Marquette County, Michigan. It was built in 1934, so it is 91 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 10 vehicles a day, projected to reach 10 by 2020. The structure is 38 ft (11.5 m) long and 16 ft wide. If it were closed, the detour would be 124.3 mi (200 km).

Location

Open in Google Maps
CarriesFw Road
CrossesBlack River
Location0.2 MI S of 478 HWY
RouteCounty Highway 0
CountyMarquette County
StateMichigan
Coordinates46.41877, -87.88956
Functional classRural Local

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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionOctober 2023
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 geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment4: Meets minimum tolerable limits to be left in place as is
Operating rating29.3 US tons
Inventory rating22.5 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckWood or timber
Main spans1
Design loadHS 20 + Mod
Structure length38 ft (11.5 m)
Longest span35 ft (10.6 m)
Deck width16 ft (4.9 m)
Roadway width16 ft (4.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic10 (1994)
Projected traffic10 by 2020
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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$77,000
NavigationNo navigation control on waterway

Frequently asked questions

When was Fw Road over Black River built?

It was built in 1934, making it 91 years old in 2025.

What condition is Fw Road over Black 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 2023.

How much traffic does Fw Road over Black River carry?

About 10 vehicles per day (1994 count).

How long is Fw Road over Black River?

The structure is 38 ft (11.5 m) long with a longest span of 35 ft (10.6 m) and a deck 16 ft wide.

Who owns Fw Road over Black River?

It is owned by the County Highway Agency.