Total bridges
43
Public highway bridges in Roscommon County
County profile · official public datasets
Roscommon County, MI
43 public highway bridges tracked in the FHWA National Bridge Inventory: 18.6% rated Good, 81.4% Fair, 0% Poor.
- 43
- Public bridges
- 18.6%
- Good condition
- 0%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Roscommon County pairs a top-1% lowest Poor-condition share among rated counties in the state with an older average build year than the state inventory.
- Top 1%
- lowest Poor share in state
- 0%
- Poor-condition share
- 43
- 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.
Roscommon County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Roscommon County ranks #1 of 83 Michigan counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 0%). Roscommon County, Michigan contains 43 public highway bridges. Roughly 18.6% are rated “Good,” 81.4% “Fair,” and 0% “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
18.6%
8 of 43 rated 7-9
Fair condition
81.4%
35 of 43 rated 5-6
Poor condition
0%
0 of 43 rated 4 or below
In-state Poor-share rank
#1 of 83
Among Michigan counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 43 NBI-tracked bridges by lowest applicable component rating.
Good 18.6% (8)
Fair 81.4% (35)
Poor 0% (0)
74.4% of Roscommon County's bridges have passed the 50-year mark
32 of the 43 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 18.6% 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.
When Roscommon County's bridges were built
43 bridges with a recorded construction year, grouped by decade
- 1930s 2
1930–1939
2 bridges
- 1940s 3
1940–1949
3 bridges
- 1950s 2
1950–1959
2 bridges
- 1960s
1960–1969
14 bridges
- 1970s
1970–1979
16 bridges
- 1980s 1
1980–1989
1 bridges
- 2000s 2
2000–2009
2 bridges
- 2010s 2
2010–2019
2 bridges
- 2020s 1
2020–2029
1 bridges
What this shows Construction peaked in the 1970s, when 16 of the county's bridges still in the inventory were built, which is 37.2% of those with a recorded year. That cohort is now 45 to 54 years old in the 2024 inventory. Its average build year is 1970, 6 years older than the Michigan average of 1976.
How Roscommon County compares with Michigan's closest counties by inventory size
The 5 Michigan counties nearest Roscommon County in number of bridges, with their condition splits. Its 0% Poor share is the 1st-lowest of these 6. Its average build year of 1970 against a peer-group mean of 1976 is 6 years older.
Showing the 5 closest of 82 Michigan counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Iosco County | 47 | 27.7% | 63.8% | 8.5% | 1972 |
| Roscommon County (this page) | 43 | 18.6% | 81.4% | 0% | 1970 |
| Missaukee County | 39 | 48.7% | 38.5% | 12.8% | 1979 |
| Dickinson County | 37 | 43.2% | 40.5% | 16.2% | 1971 |
| Emmet County | 37 | 67.6% | 32.4% | 0% | 1988 |
| Presque Isle County | 37 | 43.2% | 45.9% | 10.8% | 1972 |
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 Roscommon 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 Roscommon County, both outside Michigan so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside MI (43 bridges here).
- Franklin County, FL · 43 bridges
- Calhoun County, GA · 43 bridges
- Dickey County, ND · 43 bridges
- Slope County, ND · 43 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.
Good-condition bridges (8)
ST HELEN CONN RTE
GoodOver: DENTON CREEK
BACKUS TWP, Roscommon, MI
Built 2001 Load: 12.0 t ADT: 50
BRYAN J DRIVE
GoodOver: CHANNEL OF HOUGHTON LK
DENTON TWP SEC 2, Roscommon, MI
Built 1975 Load: 24.3 t ADT: 300
COUNTY ROAD 100
GoodOver: CUT RIVER
GERRISH TWP SEC 34, Roscommon, MI
Built 1980 Load: 41.5 t ADT: 500
M-18
GoodOver: BACKUS CREEK
9.8 MI S OF BUS-75, Roscommon, MI
Built 2019 Load: 53.5 t ADT: 2,550
COUNTY RD 100
GoodOver: CUT RIVER
SECTION 28 T23N R3W, Roscommon, MI
Built 2020 Load: 54.4 t ADT: 3,274
OLD US-27
GoodOver: WOLF CREEK
SECTION 15/16 T21N R4W, Roscommon, MI
Built 1935 Load: 56.7 t ADT: 1,276
WASHBURN ROAD
GoodOver: TOWNLINE CREEK
ROSCOMMON TWP SEC 31, Roscommon, MI
Built 2009 Load: 58.1 t ADT: 5
WACO RD
GoodOver: CREEK
400 FT E OF ROSCOMMON RD, Roscommon, MI
Built 2010 Load: 97.2 t ADT: 50
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.