US Bridges

Hedberg Road over Black River

Fair

Gogebic County, Michigan · Sec 32-33 Ironwood Twp · Structure no. 000000000003014

Built
1980
45 years old
Condition
Fair
inspected September 2024
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
69 ft
1 main span
Daily traffic
340
1986 count
Owner
County
County Highway Agency

About this bridge

Hedberg Road over Black River is a prestressed concrete box beam or girders - multiple carrying Hedberg Road over Black River in Gogebic County, Michigan. It was built in 1980, so it is 45 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 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 340 vehicles a day, projected to reach 391 by 2006. The structure is 69 ft (21 m) long and 31 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

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CarriesHedberg Road
CrossesBlack River
LocationSec 32-33 Ironwood Twp
RouteCounty Highway 0
CountyGogebic County
StateMichigan
Coordinates46.51095, -90.07316
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
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 inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating63.2 US tons
Inventory rating41.1 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans1
Design loadHS 20 + Mod
Structure length69 ft (21 m)
Longest span67 ft (20.4 m)
Deck width31 ft (9.4 m)
Roadway width31 ft (9.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic340 (1986)
Projected traffic391 by 2006
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 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$485,000
NavigationNo navigation control on waterway

Frequently asked questions

When was Hedberg Road over Black River built?

It was built in 1980, making it 45 years old in 2025.

What condition is Hedberg 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 September 2024.

How much traffic does Hedberg Road over Black River carry?

About 340 vehicles per day (1986 count).

How long is Hedberg Road over Black River?

The structure is 69 ft (21 m) long with a longest span of 67 ft (20.4 m) and a deck 31 ft wide.

Who owns Hedberg Road over Black River?

It is owned by the County Highway Agency.