Total bridges
80
Public highway bridges in Arenac County
County profile · official public datasets
Arenac County, MI
80 public highway bridges tracked in the FHWA National Bridge Inventory: 25% rated Good, 56.3% Fair, 18.8% Poor.
- 80
- Public bridges
- 25%
- Good condition
- 18.8%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Arenac County pairs a higher-than-median Poor-condition share among rated counties in the state with an older average build year than the state inventory.
- 75th
- of 83 on Poor share
- 18.8%
- Poor-condition share
- 80
- public highway bridges
- 1970
- avg year built
Poor is an FHWA condition category from the lowest applicable component rating (4 or below), not a live crossing-safety or closure decision. Rankings cover counties with at least five public highway bridges.
Arenac County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Arenac County ranks #75 of 83 Michigan counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 18.8%). Arenac County, Michigan contains 80 public highway bridges. Roughly 25% are rated “Good,” 56.3% “Fair,” and 18.8% “Poor.” Poor means the lowest applicable deck, superstructure, substructure, or culvert rating is 4 or below on the 0–9 NBI scale. It is a condition category, not a live safety or closure decision.
Responsible agencies inspect covered bridges on risk-based intervals under current NBIS rules and submit inventory data to FHWA annually. The list below shows every NBI-tracked bridge in the county. Use the “Sort by” controls to change the ordering, and click any row for its reported inspection date, traffic count, and condition fields.
Source: FHWA National Bridge Inventory. See methodology for full definitions.
Good condition
25%
20 of 80 rated 7-9
Fair condition
56.3%
45 of 80 rated 5-6
Poor condition
18.8%
15 of 80 rated 4 or below
In-state Poor-share rank
#75 of 83
Among Michigan counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 80 NBI-tracked bridges by lowest applicable component rating.
Good 25% (20)
Fair 56.3% (45)
Poor 18.8% (15)
Arenac County's Poor-condition bridges carry 41,657 vehicle crossings a day
That is 14.9% of the county's reported daily bridge traffic on 18.8% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 2,777 crossings a day against 3,534 for a Good-condition one. A Poor rating is a condition category, not a closure or a live safety judgement; it means the lowest applicable component rating is 4 or below.
Computed over the 80 of 80 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
60% of Arenac County's bridges have passed the 50-year mark
48 of the 80 bridges with a recorded construction year were built in 1974 or earlier. Age alone is not a defect: a well-maintained older bridge can rate Good, and 25% of this county's inventory does. Even so, this older cohort is the population from which future Poor ratings are drawn, which is why the age profile below matters alongside the condition split above.
Cutoff derives from the 2024 release year minus a 50-year design life. Source: FHWA National Bridge Inventory, 2024 release.
One structure carries 34.4% of the county's Poor-condition bridge traffic
STERLING ROAD over I-75, built 1968, carries 14,350 vehicles a day, the most of any Poor-rated structure here. The county's Poor-condition exposure is concentrated rather than evenly spread, so the 15-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 41,657 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Arenac County's bridges were built
80 bridges with a recorded construction year, grouped by decade
- 1900s 1
1900–1909
1 bridges
- 1910s 4
1910–1919
4 bridges
- 1920s 2
1920–1929
2 bridges
- 1930s 7
1930–1939
7 bridges
- 1940s 2
1940–1949
2 bridges
- 1950s 3
1950–1959
3 bridges
- 1960s
1960–1969
23 bridges
- 1970s
1970–1979
10 bridges
- 1980s
1980–1989
10 bridges
- 1990s 7
1990–1999
7 bridges
- 2000s 8
2000–2009
8 bridges
- 2010s 2
2010–2019
2 bridges
- 2020s 1
2020–2029
1 bridges
What this shows Construction peaked in the 1960s, when 23 of the county's bridges still in the inventory were built, which is 28.8% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year is 1970, 6 years older than the Michigan average of 1976.
How Arenac County compares with Michigan's closest counties by inventory size
The 5 Michigan counties nearest Arenac County in number of bridges, with their condition splits. Its 18.8% Poor share is the 4th-lowest of these 6. Its average build year of 1970 against a peer-group mean of 1979 is 9 years older.
Showing the 5 closest of 82 Michigan counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Delta County | 84 | 38.1% | 60.7% | 1.2% | 1974 |
| Mecosta County | 80 | 36.3% | 58.8% | 5% | 1982 |
| Arenac County (this page) | 80 | 25% | 56.3% | 18.8% | 1970 |
| Cheboygan County | 73 | 21.9% | 58.9% | 19.2% | 1975 |
| Barry County | 69 | 26.1% | 49.3% | 24.6% | 1977 |
| Baraga County | 68 | 61.8% | 30.9% | 7.4% | 1988 |
Each share is of that county's own total tracked bridges; peers are the counties with 5 or more bridges whose inventory size is closest to Arenac County's. Source: FHWA National Bridge Inventory, 2024 release.
Nationwide counties with similar inventory size or average build year
Two NBI-derived peer sets for Arenac County, both outside Michigan so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside MI (80 bridges here).
- Moffat County, CO · 80 bridges
- Burke County, GA · 80 bridges
- Gooding County, ID · 80 bridges
- Madison County, ID · 80 bridges
Similar average build year
Nearest mean year-built outside MI (1970 here).
- Hamilton County, OH · avg 1970 · 783 bridges
- Yavapai County, AZ · avg 1970 · 543 bridges
- Garfield County, OK · avg 1970 · 504 bridges
- San Luis Obispo County, CA · avg 1970 · 401 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Poor-condition bridges (15)
NOGGLE ROAD
PoorOver: BIG CREEK A DRAIN
0.3 MI E OF LENTNER RD, Arenac, MI
Built 1920 Load: 5.8 t ADT: 198
OSTRANDER RD
PoorOver: BIG CREEK A DRAIN
0.3 MI W OF M-65, Arenac, MI
Built 1917 Load: 6.6 t ADT: 90
BLACK ROAD
PoorOver: BIG CREEK A DRAIN
0.6 MI S OF TWINING RD, Arenac, MI
Built 1917 Load: 9.1 t ADT: 30
LENTNER ROAD
PoorOver: BIG CREEK A DRAIN
500 FT N OF NOGGLE ROAD, Arenac, MI
Built 1917 Load: 18.5 t ADT: 5
MACKINAW ROAD
PoorOver: AUGRES RIVER
0.8 MI N OF BESSINGER RD, Arenac, MI
Built 1985 Load: 24.9 t ADT: 200
M-61
PoorOver: M BR PINE RIVER
1.7 MI W OF STANDISH, Arenac, MI
Built 1952 Load: 27.5 t ADT: 4,242
OLD M-76
PoorOver: NORTH BR PINE RIVER
2.6 MILES NW OF STANDISH, Arenac, MI
Built 1932 Load: 29.4 t ADT: 2,554
STERLING ROAD
PoorOver: I-75
2.0 MI W OF STERLING, Arenac, MI
Built 1968 Load: 30.8 t ADT: 14,350
M-61
PoorOver: M BR PINE RIVER
2.0 MI W OF STANDISH, Arenac, MI
Built 1952 Load: 31.8 t ADT: 4,242
M-33
PoorOver: I-75
1.0 MI N OF ALGER, Arenac, MI
Built 1968 Load: 31.8 t ADT: 4,124
DEEP RIVER
PoorOver: S BRANCH PINE RIVER
400 FT N OF BORDEAU, Arenac, MI
Built 1979 Load: 34.3 t ADT: 25
FOCO ROAD
PoorOver: N BR PINE RIVER
0.3 MI S OF US-23, Arenac, MI
Built 1974 Load: 38.2 t ADT: 235
M-33 CONN
PoorOver: LAKE STATE RR & OLD M-76
1.0 MI N OF ALGER, Arenac, MI
Built 1968 Load: 42.1 t ADT: 4,124
KRAUSHAAR ROAD
PoorOver: PINE RIVER
N OF PINE RIVER, Arenac, MI
Built 1993 Load: 49.9 t ADT: 100
I-75 SB
PoorOver: N BRANCH PINE RIVER
0.1 MI S OF MI PT 193, Arenac, MI
Built 1968 Load: 97.2 t ADT: 7,138
Read our methodology - how this data is sourced, computed, and verified.
Related
Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainBridges
Every figure on PlainBridges is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. NBI condition categories reflect the latest reported inventory record, not a live safety, closure, or travel decision.