Total bridges
63
Public highway bridges in Gladwin County
County profile · official public datasets
Gladwin County, MI
63 public highway bridges tracked in the FHWA National Bridge Inventory: 47.6% rated Good, 46% Fair, 6.3% Poor.
- 63
- Public bridges
- 47.6%
- Good condition
- 6.3%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Gladwin County pairs a top-quartile lowest Poor-condition share among rated counties in the state with a newer average build year than the state inventory.
- Top 25%
- lowest Poor share in state
- 6.3%
- Poor-condition share
- 63
- public highway bridges
- 1981
- 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.
Gladwin County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Gladwin County ranks #21 of 83 Michigan counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 6.3%). Gladwin County, Michigan contains 63 public highway bridges. Roughly 47.6% are rated “Good,” 46% “Fair,” and 6.3% “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
47.6%
30 of 63 rated 7-9
Fair condition
46%
29 of 63 rated 5-6
Poor condition
6.3%
4 of 63 rated 4 or below
In-state Poor-share rank
#21 of 83
Among Michigan counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 63 NBI-tracked bridges by lowest applicable component rating.
Good 47.6% (30)
Fair 46% (29)
Poor 6.3% (4)
Gladwin County's Poor-condition bridges carry 9,716 vehicle crossings a day
That is 12.3% of the county's reported daily bridge traffic on 6.3% of its bridges: Poor-condition structures carry more traffic than their share of the inventory. Each Poor bridge averages 2,429 crossings a day against 797 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 63 of 63 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
28.6% of Gladwin County's bridges have passed the 50-year mark
18 of the 63 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 47.6% 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 62.8% of the county's Poor-condition bridge traffic
M-18 over TOBACCO RIVER, built 1939, carries 6,100 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 4-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 9,716 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Gladwin County's bridges were built
63 bridges with a recorded construction year, grouped by decade
- 1910s 2
1910–1919
2 bridges
- 1920s 3
1920–1929
3 bridges
- 1930s 2
1930–1939
2 bridges
- 1950s 5
1950–1959
5 bridges
- 1960s 3
1960–1969
3 bridges
- 1970s
1970–1979
11 bridges
- 1980s
1980–1989
13 bridges
- 1990s
1990–1999
9 bridges
- 2000s
2000–2009
8 bridges
- 2010s 4
2010–2019
4 bridges
- 2020s 3
2020–2029
3 bridges
What this shows Construction peaked in the 1980s, when 13 of the county's bridges still in the inventory were built, which is 20.6% of those with a recorded year. That cohort is now 35 to 44 years old in the 2024 inventory. Its average build year is 1981, 5 years newer than the Michigan average of 1976.
How Gladwin County compares with Michigan's closest counties by inventory size
The 5 Michigan counties nearest Gladwin County in number of bridges, with their condition splits. Its 6.3% Poor share is the 2nd-lowest of these 6. Its average build year of 1981 against a peer-group mean of 1976 is 5 years newer.
Showing the 5 closest of 82 Michigan counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Mason County | 66 | 39.4% | 53% | 7.6% | 1977 |
| Newaygo County | 65 | 43.1% | 46.2% | 10.8% | 1979 |
| Ontonagon County | 64 | 37.5% | 46.9% | 15.6% | 1970 |
| Wexford County | 64 | 26.6% | 67.2% | 6.3% | 1986 |
| Mackinac County | 63 | 25.4% | 55.6% | 19% | 1966 |
| Gladwin County (this page) | 63 | 47.6% | 46% | 6.3% | 1981 |
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 Gladwin 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 Gladwin County, both outside Michigan so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside MI (63 bridges here).
- Highlands County, FL · 63 bridges
- Chattahoochee County, GA · 63 bridges
- Red River County, LA · 63 bridges
- Lincoln County, ME · 63 bridges
Similar average build year
Nearest mean year-built outside MI (1981 here).
- Franklin County, OH · avg 1981 · 922 bridges
- Greenville County, SC · avg 1981 · 635 bridges
- Montgomery County, OH · avg 1981 · 632 bridges
- McLean County, IL · avg 1981 · 624 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Poor-condition bridges (4)
HIGHWOOD ROAD
PoorOver: TITTABAWASEE RIVER
3.5 MI E OF M 30, Gladwin, MI
Built 1984 Load: 22.4 t ADT: 495
M-18
PoorOver: TOBACCO RIVER
IN BEAVERTON, Gladwin, MI
Built 1939 Load: 27.5 t ADT: 6,100
DALE ROAD
PoorOver: TOBACCO RIVER
2.9 MI E OF M18, Gladwin, MI
Built 1970 Load: 39.2 t ADT: 585
M-30
PoorOver: TITTABAWASSEE RIVER
1.5 MI SW&W OF OGEMAW COL, Gladwin, MI
Built 1928 Load: 46.0 t ADT: 2,536
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.