Total bridges
84
Public highway bridges in Delta County
County profile · official public datasets
Delta County, MI
84 public highway bridges tracked in the FHWA National Bridge Inventory: 38.1% rated Good, 60.7% Fair, 1.2% Poor.
- 84
- Public bridges
- 38.1%
- Good condition
- 1.2%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Delta County posts a top-10% lowest Poor-condition share among rated counties in the state across rated county bridge inventory.
- Top 6%
- lowest Poor share in state
- 1.2%
- Poor-condition share
- 84
- public highway bridges
- 1974
- 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.
Delta County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Delta County ranks #5 of 83 Michigan counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 1.2%). Delta County, Michigan contains 84 public highway bridges. Roughly 38.1% are rated “Good,” 60.7% “Fair,” and 1.2% “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
38.1%
32 of 84 rated 7-9
Fair condition
60.7%
51 of 84 rated 5-6
Poor condition
1.2%
1 of 84 rated 4 or below
In-state Poor-share rank
#5 of 83
Among Michigan counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 84 NBI-tracked bridges by lowest applicable component rating.
Good 38.1% (32)
Fair 60.7% (51)
Poor 1.2% (1)
Delta County's Poor-condition bridges carry 444 vehicle crossings a day
That is 0.2% of the county's reported daily bridge traffic on 1.2% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 444 crossings a day against 2,163 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 84 of 84 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
54.8% of Delta County's bridges have passed the 50-year mark
46 of the 84 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 38.1% 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 100% of the county's Poor-condition bridge traffic
ROUTE 410 over TEN MILE CREEK, built 1939, carries 444 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 1-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 444 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Delta County's bridges were built
84 bridges with a recorded construction year, grouped by decade
- 1920s 1
1920–1929
1 bridges
- 1930s
1930–1939
13 bridges
- 1940s
1940–1949
8 bridges
- 1950s 4
1950–1959
4 bridges
- 1960s
1960–1969
10 bridges
- 1970s
1970–1979
17 bridges
- 1980s 4
1980–1989
4 bridges
- 1990s 4
1990–1999
4 bridges
- 2000s
2000–2009
12 bridges
- 2010s
2010–2019
10 bridges
- 2020s 1
2020–2029
1 bridges
What this shows Construction peaked in the 1970s, when 17 of the county's bridges still in the inventory were built, which is 20.2% of those with a recorded year. That cohort is now 45 to 54 years old in the 2024 inventory. Its average build year (1974) matches the Michigan average (1976).
How Delta County compares with Michigan's closest counties by inventory size
The 5 Michigan counties nearest Delta County in number of bridges, with their condition splits. Its 1.2% Poor share is the 1st-lowest of these 6. Its average build year of 1974 against a peer-group mean of 1978 is in line with the group.
Showing the 5 closest of 82 Michigan counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Clare County | 96 | 38.5% | 58.3% | 3.1% | 1984 |
| Menominee County | 96 | 47.9% | 42.7% | 9.4% | 1978 |
| Delta County (this page) | 84 | 38.1% | 60.7% | 1.2% | 1974 |
| Arenac County | 80 | 25% | 56.3% | 18.8% | 1970 |
| Mecosta County | 80 | 36.3% | 58.8% | 5% | 1982 |
| Cheboygan County | 73 | 21.9% | 58.9% | 19.2% | 1975 |
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 Delta 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 Delta County, both outside Michigan so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside MI (84 bridges here).
- Chaffee County, CO · 84 bridges
- Elbert County, GA · 84 bridges
- Glynn County, GA · 84 bridges
- Paulding County, GA · 84 bridges
Similar average build year
Nearest mean year-built outside MI (1974 here).
- Knox County, TN · avg 1974 · 588 bridges
- Summit County, OH · avg 1974 · 563 bridges
- Onondaga County, NY · avg 1974 · 472 bridges
- Orange County, NY · avg 1974 · 472 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Fair-condition bridges (51)
COUNTY ROAD H 42
FairOver: RAPID RIVER
10.5 M N 1.5 M W RAPID RI, Delta, MI
Built 1964 Load: 12.3 t ADT: 21
COUNTY ROAD I 24
FairOver: TACOOSH RIVER
1 M N 1 M W RAPID RIVER, Delta, MI
Built 1969 Load: 14.3 t ADT: 73
B-28 (10TH RD)
FairOver: BARK RIVER
3.5 MI SE OF BARK RIVER, Delta, MI
Built 1975 Load: 19.4 t ADT: 149
ROUTE 519
FairOver: ESCANABA RIVER
0.7 MILES NE OF CORNELL, Delta, MI
Built 1984 Load: 20.1 t ADT: 305
USFS RTE 2231
FairOver: STURGEON RIVER
SEC 17 NAHMA TWP, Delta, MI
Built 1948 Load: 21.4 t ADT: 10
ROUTE 444
FairOver: W BR WHITEFISH R
3 MI E OF USH 41, Delta, MI
Built 1960 Load: 22.0 t ADT: 68
ROUTE 537
FairOver: FORD RIVER
8 MI W OF ESCANABA, Delta, MI
Built 1977 Load: 22.0 t ADT: 219
COUNTY ROAD H 36
FairOver: SQUAW CREEK
3.5 M W 1 M S OF ROCK, Delta, MI
Built 1940 Load: 23.7 t ADT: 40
ROUTE 515
FairOver: DAY S RIVER
2 MI N OF GLADSTONE, Delta, MI
Built 1940 Load: 26.2 t ADT: 783
ROUTE 410
FairOver: TEN MILE CREEK
13 MI W OF ESCANABA, Delta, MI
Built 1958 Load: 26.4 t ADT: 444
COUNTY ROAD B 33
FairOver: BARK RIVER
5.5 MI S E OF BARK RIVER, Delta, MI
Built 1979 Load: 26.9 t ADT: 30
ROUTE 432
FairOver: RAPID RIVER
3.5 MI W OF USH 41, Delta, MI
Built 1939 Load: 28.8 t ADT: 145
ROUTE 499
FairOver: STURGEON RIVER
.2 MI W OF NAHMA, Delta, MI
Built 1985 Load: 30.1 t ADT: 81
US-41
FairOver: RAPID RIVER
7.2 MI N OF US-2, Delta, MI
Built 1937 Load: 32.4 t ADT: 2,264
BATH HOUSE RD
FairOver: MARINA OUTLET
ESCANABA MARINA, Delta, MI
Built 1934 Load: 32.4 t ADT: 1,500
COUNTY ROAD E 2
FairOver: FORD RIVER
3.5 M W 0.5 M S WOODLAWN, Delta, MI
Built 1940 Load: 32.7 t ADT: 7
ROUTE 533
FairOver: FORD RIVER
6 MILES W OF ESCANABA, Delta, MI
Built 1958 Load: 33.0 t ADT: 1,487
US-2 US-41
FairOver: FORD RIVER
0.5 MI E OF HYDE, Delta, MI
Built 1941 Load: 33.4 t ADT: 13,600
M-35
FairOver: FORD RIVER
4.0 MI SW OF ESCANABA, Delta, MI
Built 1932 Load: 33.4 t ADT: 3,800
ROUTE 414
FairOver: FORD RIVER
7 MI W OF ESCANABA, Delta, MI
Built 1958 Load: 34.0 t ADT: 605
ROUTE 428
FairOver: TACOOSH RIVER
10 MI N OF GLADSTONE, Delta, MI
Built 1980 Load: 34.0 t ADT: 492
COUNTY ROAD A 26
FairOver: FORD RIVER
2 MI W 1 MI S OF ESCANABA, Delta, MI
Built 2008 Load: 34.0 t ADT: 137
FED FOREST HWY 13
FairOver: STURGEON RIVER
7 MI N OF NAHMA JCT, Delta, MI
Built 1941 Load: 34.7 t ADT: 467
US-2 WB & US-41 SB
FairOver: WCL RR
E LTS OF GLADSTONE, Delta, MI
Built 1971 Load: 36.9 t ADT: 4,661
US-2 EB & US-41 NB
FairOver: WCL RR
E LTS OF GLADSTONE, Delta, MI
Built 1970 Load: 36.9 t ADT: 4,661
COUNTY ROAD I 14
FairOver: RAPID RIVER
5.0 M N 1 M E RAPID RIVER, Delta, MI
Built 1940 Load: 36.9 t ADT: 111
US-2 EB & US-41 NB
FairOver: DAYS RIVER
3.5 MI N OF M-35, Delta, MI
Built 1971 Load: 39.9 t ADT: 4,267
COUNTY ROAD I 10
FairOver: WEST BR WHITEFISH RIVER
4.2 MILES EAST OF US 41, Delta, MI
Built 1966 Load: 39.9 t ADT: 100
US-2
FairOver: TOCOOSH CREEK
0.2 MI E OF US-41, Delta, MI
Built 1990 Load: 40.2 t ADT: 8,505
ROUTE 497
FairOver: STURGEON RIVER
.5 MI N OF NAHMA JCT, Delta, MI
Built 2008 Load: 40.8 t ADT: 55
US-2 US-41
FairOver: PORTAGE CREEK
3.4 MI W OF ESCANABA, Delta, MI
Built 1928 Load: 41.8 t ADT: 14,094
US-2 US-41
FairOver: WILLOW CREEK
IN ESCANABA(W LUDINGTON), Delta, MI
Built 1979 Load: 43.1 t ADT: 12,255
US-2
FairOver: RAPID RIVER
0.4 MI E OF US-41, Delta, MI
Built 1931 Load: 43.1 t ADT: 8,505
M-35
FairOver: PORTAGE CREEK
S LTS OF ESCANABA, Delta, MI
Built 1932 Load: 43.4 t ADT: 6,441
ROUTE 535
FairOver: BARK RIVER
10 MI SW OF ESCANABA, Delta, MI
Built 1961 Load: 43.4 t ADT: 234
COUNTY ROAD B 36
FairOver: BARK RIVER
7 MI S E OF BARK RIVER, Delta, MI
Built 1974 Load: 44.1 t ADT: 20
COUNTY ROAD I 10
FairOver: EAST BR WHITEFISH RIVER
6.4 MILES EAST OF US 41, Delta, MI
Built 1992 Load: 45.4 t ADT: 64
US-2
FairOver: WCL RR
2.7 MI SE OF RAPID RIVER, Delta, MI
Built 1935 Load: 46.7 t ADT: 8,019
ROUTE 414
FairOver: TEN MILE CREEK
10 MI W OF ESCANABA, Delta, MI
Built 1961 Load: 47.3 t ADT: 605
US-2
FairOver: WHITEFISH RIVER
1.1 MI E OF RAPID RIVER, Delta, MI
Built 1936 Load: 48.9 t ADT: 7,343
COUNTY ROAD H 44
FairOver: SQUAW CREEK
5.5 MI WEST OF M 35, Delta, MI
Built 1979 Load: 49.2 t ADT: 20
US-2
FairOver: BIG FISHDAM RIVER
1.5 MI NE OF ISABELLA, Delta, MI
Built 1936 Load: 49.6 t ADT: 3,462
ROUTE 420
FairOver: ESCANABA RIVER
2 MI WEST OF GLADSTONE, Delta, MI
Built 1974 Load: 50.5 t ADT: 1,539
COUNTY ROAD G 8
FairOver: TACOOSH RIVER
2.5 MI N OF PERKINS, Delta, MI
Built 1972 Load: 50.5 t ADT: 19
M-35
FairOver: BARK RIVER
2.5 MI N OF MENOMINEE COL, Delta, MI
Built 1948 Load: 53.1 t ADT: 3,418
US-41
FairOver: TACOOSH CREEK
0.4 MI N OF US-2, Delta, MI
Built 1993 Load: 56.4 t ADT: 2,760
US-2
FairOver: LITTLE FISHDAM RIVER
2.0 MI NE OF ISABELLA, Delta, MI
Built 1936 Load: 58.3 t ADT: 3,462
COUNTY ROAD B 30
FairOver: BARK RIVER
3 MI SOUTH OF BARK RIVER, Delta, MI
Built 1978 Load: 62.2 t ADT: 100
COUNTY ROAD J 11
FairOver: OGONTZ RIVER
4 MI W 0.5 MI S NAHMA JCT, Delta, MI
Built 1963 Load: 68.4 t ADT: 4
COUNTY ROAD H 1
FairOver: RAPID RIVER
3 M N 1 M E OF ROCK, Delta, MI
Built 1967 Load: 68.4 t ADT: 54
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.