Total bridges
63
Public highway bridges in Mackinac County
County profile · official public datasets
Mackinac County, MI
63 public highway bridges tracked in the FHWA National Bridge Inventory: 25.4% rated Good, 55.6% Fair, 19% Poor.
- 63
- Public bridges
- 25.4%
- Good condition
- 19%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Mackinac 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.
- 76th
- of 83 on Poor share
- 19%
- Poor-condition share
- 63
- public highway bridges
- 1966
- 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.
Mackinac County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Mackinac County ranks #76 of 83 Michigan counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 19%). Mackinac County, Michigan contains 63 public highway bridges. Roughly 25.4% are rated “Good,” 55.6% “Fair,” and 19% “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
25.4%
16 of 63 rated 7-9
Fair condition
55.6%
35 of 63 rated 5-6
Poor condition
19%
12 of 63 rated 4 or below
In-state Poor-share rank
#76 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 25.4% (16)
Fair 55.6% (35)
Poor 19% (12)
Mackinac County's Poor-condition bridges carry 20,547 vehicle crossings a day
That is 21.9% of the county's reported daily bridge traffic on 19% of its bridges: Poor-condition structures carry more traffic than their share of the inventory. Each Poor bridge averages 1,712 crossings a day against 444 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.
69.8% of Mackinac County's bridges have passed the 50-year mark
44 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 25.4% 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 20% of the county's Poor-condition bridge traffic
US-2 over WCL RR, built 1938, carries 4,114 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 12-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 20,547 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Mackinac County's bridges were built
63 bridges with a recorded construction year, grouped by decade
- 1920s 1
1920–1929
1 bridges
- 1930s 7
1930–1939
7 bridges
- 1940s 4
1940–1949
4 bridges
- 1950s 6
1950–1959
6 bridges
- 1960s
1960–1969
25 bridges
- 1970s 5
1970–1979
5 bridges
- 1980s 5
1980–1989
5 bridges
- 1990s 6
1990–1999
6 bridges
- 2000s 1
2000–2009
1 bridges
- 2010s 3
2010–2019
3 bridges
What this shows Construction peaked in the 1960s, when 25 of the county's bridges still in the inventory were built, which is 39.7% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year is 1966, 10 years older than the Michigan average of 1976.
How Mackinac County compares with Michigan's closest counties by inventory size
The 5 Michigan counties nearest Mackinac County in number of bridges, with their condition splits. Its 19% Poor share is the 6th-lowest of these 6. Its average build year of 1966 against a peer-group mean of 1979 is 13 years older.
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 |
| Gladwin County | 63 | 47.6% | 46% | 6.3% | 1981 |
| Mackinac County (this page) | 63 | 25.4% | 55.6% | 19% | 1966 |
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 Mackinac 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 Mackinac 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 (1966 here).
- Butler County, KS · avg 1966 · 591 bridges
- Grafton County, NH · avg 1966 · 544 bridges
- Queens County, NY · avg 1966 · 514 bridges
- Lehigh County, PA · avg 1966 · 381 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
All bridges (63)
3332
FairOver: CARP RIVER
3.062 WEST ON 3332, Mackinac, MI
Built 1951 Load: 14.6 t ADT: 15
KENNETH ROAD
FairOver: N. BRANCH CARP RIVER
3 M S & 5 M E OF OZARK, Mackinac, MI
Built 1979 Load: 18.5 t ADT: 125
TOWNLINE ROAD
FairOver: MUNESCONG RIVER
6.25 MI W OF PICKFORD, Mackinac, MI
Built 1966 Load: 21.8 t ADT: 60
USFS RTE 3303
FairOver: BREVOORT RIVER
1.3 MI W CO RTE H57, Mackinac, MI
Built 1963 Load: 24.0 t ADT: 10
M-117
FairOver: DOE CREEK
2.2 MI N OF ENGADINE, Mackinac, MI
Built 1954 Load: 25.6 t ADT: 1,760
BAY RD
FairOver: I-75 SB
1.7 MI S OF CHIPPEWA COL, Mackinac, MI
Built 1963 Load: 32.4 t ADT: 75
MACKINAC TRL. FH41
FairOver: RABBITS BACK CREEK
1 MI N B L 75 ON CTY RD 4, Mackinac, MI
Built 1930 Load: 32.7 t ADT: 2,020
MACKINAC TRL FH41
FairOver: CLEAR CREEK
4.3 MI N OF M-134, Mackinac, MI
Built 1930 Load: 32.7 t ADT: 350
US-2
FairOver: MILLECOQUIN RIVER
4.8 MI E OF M-117, Mackinac, MI
Built 1940 Load: 33.0 t ADT: 3,813
KENNETH ROAD
FairOver: TAYLOR CREEK
3 M S & 3 M E OF OZARK, Mackinac, MI
Built 1975 Load: 33.4 t ADT: 37
CHARLES MORAN RD
FairOver: I-75 NB
2.4 MI NE OF M-123, Mackinac, MI
Built 1963 Load: 33.7 t ADT: 75
MANISTIQUE LAKE RO
FairOver: PORTAGE CREEK
0.25 MI N OF CURTIS, Mackinac, MI
Built 1940 Load: 34.7 t ADT: 1,125
KENNETH ROAD
FairOver: N BRANCH CARP RIVER
3 M S & 5 M E OF OZARK, Mackinac, MI
Built 1949 Load: 35.0 t ADT: 70
KENNETH ROAD
FairOver: TAYLOR CREEK
3 M S & 3 M E OF OZARK, Mackinac, MI
Built 1974 Load: 35.0 t ADT: 125
I-75 NB
FairOver: OLD US-2
4.0 MI NE OF M-123, Mackinac, MI
Built 1963 Load: 36.0 t ADT: 2,039
I-75 NB
FairOver: PORTAGE ST
IN ST IGNACE PORTAGE ST, Mackinac, MI
Built 1960 Load: 36.9 t ADT: 2,555
I-75 SB
FairOver: PORTAGE ST
IN ST IGNACE PORTAGE ST, Mackinac, MI
Built 1960 Load: 36.9 t ADT: 2,555
US-2
FairOver: CUT RIVER
4.3 MI NW OF BREVORT, Mackinac, MI
Built 1947 Load: 37.6 t ADT: 4,450
I-75 SB
FairOver: OLD US-2
4.0 MI NE OF M-123, Mackinac, MI
Built 1963 Load: 37.6 t ADT: 4,400
M-134
FairOver: MCKAYS CREEK
3.4 MI W OF CHIPPEWA COL, Mackinac, MI
Built 1993 Load: 37.9 t ADT: 975
M-134
FairOver: PINE RIVER
1.0 MI E OF I-75, Mackinac, MI
Built 1958 Load: 39.9 t ADT: 1,404
I-75 SB
FairOver: PINE RIVER
3.6 MI S OF CHIPPEWA COL, Mackinac, MI
Built 1963 Load: 40.2 t ADT: 1,825
US-2
FairOver: HOG ISLAND CREEK
14.8 MI E OF M-117, Mackinac, MI
Built 1939 Load: 40.5 t ADT: 3,668
US-2
FairOver: DAVENPORT CREEK
16.0 MI E OF M-117, Mackinac, MI
Built 1939 Load: 40.8 t ADT: 3,668
I-75 SB
FairOver: CARP RIVER
4.6 MI N OF M-123, Mackinac, MI
Built 1964 Load: 40.8 t ADT: 4,400
I-75 NB
FairOver: CARP RIVER
4.6 MI N OF M-123, Mackinac, MI
Built 1964 Load: 41.8 t ADT: 2,039
M-123
FairOver: CARP RIVER
2.8 MI NW OF GREEN, Mackinac, MI
Built 1961 Load: 43.4 t ADT: 1,041
US-2 I-75BL
FairOver: I-75
IN ST IGNACE I-75, Mackinac, MI
Built 1957 Load: 44.4 t ADT: 7,550
MANISTIQUE LAKE RO
FairOver: PORTAGE CREEK
1.5 MI N OF CURTIS, Mackinac, MI
Built 1960 Load: 45.7 t ADT: 1,762
M-134
FairOver: NUNNS CREEK
6.2 MI SE OF I-75, Mackinac, MI
Built 1953 Load: 48.9 t ADT: 1,404
I-75 BL
FairOver: I-75
@ N JCT I-75 BL, Mackinac, MI
Built 1960 Load: 49.9 t ADT: 4,350
I-75 NB
FairOver: PINE RIVER
3.6 MI S OF CHIPPEWA COL, Mackinac, MI
Built 1963 Load: 50.5 t ADT: 1,508
CARL WORTH RD FH40
FairOver: LITTLE BREVORT RIVER
4.0 MI E OF US-2, Mackinac, MI
Built 2013 Load: 52.2 t ADT: 480
USFS RTE 3108
FairOver: LITTLE BREVOORT RIVER
1.7 MI N US-2, Mackinac, MI
Built 1979 Load: 60.3 t ADT: 175
US-2
FairOver: POINT AUCHENE CREEK
10.9 MI W OF ST IGNACE, Mackinac, MI
Built 1937 Load: 60.6 t ADT: 4,156
HIAWATHA TRAIL
GoodOver: MILLECOQUINS RIVER
2.2 MI E OF ENGADINE, Mackinac, MI
Built 1992 Load: 27.9 t ADT: 305
ISLAND 8 ROAD
GoodOver: HILL CHANNEL LAKE HURON
2 M E & 1 M S OF CEDARVIL, Mackinac, MI
Built 1984 Load: 29.5 t ADT: 250
HIAWATHA TRAIL
GoodOver: BLACK RIVER
1.0 MI E OF GILCHRIST, Mackinac, MI
Built 1990 Load: 29.8 t ADT: 250
CHARLES MORAN RD
GoodOver: I-75 SB
2.4 MI NE OF M-123, Mackinac, MI
Built 1963 Load: 31.1 t ADT: 75
TAYLOR ROAD
GoodOver: TAYLOR CREEK
2 MI S & 0.5 MI W OF PICK, Mackinac, MI
Built 1967 Load: 32.7 t ADT: 164
THREE MILE ROAD
GoodOver: MUNUSCONG RIVER
9.2MI N OF HESSEL AND M-1, Mackinac, MI
Built 1978 Load: 34.3 t ADT: 40
EAST LAKE RD FH85
GoodOver: CARP RIVER
5.0 MI N OF MORAN, Mackinac, MI
Built 1986 Load: 35.0 t ADT: 75
RUTLEDGE ROAD
GoodOver: MUNUSCONG RIVER
1.5 M S 2 M W OF PICKFORD, Mackinac, MI
Built 2006 Load: 35.6 t ADT: 60
ST IGNACE RD FH84
GoodOver: NUNS CREEK
4.0 MI E OF M-134, Mackinac, MI
Built 1985 Load: 37.3 t ADT: 220
US-2
GoodOver: BREVORT RIVER
6.9 MI SE OF BREVORT, Mackinac, MI
Built 2019 Load: 37.9 t ADT: 4,400
BAY RD
GoodOver: I-75 NB
1.7 MI S OF CHIPPEWA COL, Mackinac, MI
Built 1963 Load: 40.2 t ADT: 75
HILL ISLAND ROAD
GoodOver: FLOWER BAY LAKE HURON
0.25 MI S OF M-134, Mackinac, MI
Built 2018 Load: 42.1 t ADT: 606
ONE MILE ROAD
GoodOver: TAYLOR CREEK
2.5 M S 1 M W OF PICKFORD, Mackinac, MI
Built 1995 Load: 44.1 t ADT: 40
ROADSIDE PARK RD
GoodOver: CREEK
2.6 E OF NAUBINWAY, Mackinac, MI
Built 1990 Load: 48.0 t ADT: 100
MACKINAC TRL FH41
GoodOver: CARP RIVER
2.5 MILES S OF M-134, Mackinac, MI
Built 1927 Load: 97.2 t ADT: 200
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.