Total bridges
523
Public highway bridges in Kent County
County profile · official public datasets
523 public highway bridges tracked in the FHWA National Bridge Inventory: 36.9% rated Good, 57.7% Fair, 5.4% Poor.
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Kent County posts a top-quartile lowest Poor-condition share among rated counties in the state across large county bridge inventory.
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.
According to the Federal Highway Administration's 2024 National Bridge Inventory, Kent County ranks #13 of 83 Michigan counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 5.4%). Kent County, Michigan contains 523 public highway bridges. Roughly 36.9% are rated “Good,” 57.7% “Fair,” and 5.4% “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.
Total bridges
523
Public highway bridges in Kent County
Good condition
36.9%
193 of 523 rated 7-9
Fair condition
57.7%
302 of 523 rated 5-6
Poor condition
5.4%
28 of 523 rated 4 or below
In-state Poor-share rank
#13 of 83
Among Michigan counties with 5+ bridges, lower share ranks better
Share of 523 NBI-tracked bridges by lowest applicable component rating.
That is 6.8% of the county's reported daily bridge traffic on 5.4% of its bridges: Poor-condition structures carry more traffic than their share of the inventory. Each Poor bridge averages 20,519 crossings a day against 12,442 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 519 of 523 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
290 of the 523 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 36.9% 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.
I-296 (US-131) NB over US-131 BR (LEONARD), built 1961, carries 50,972 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 28-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 574,530 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
523 bridges with a recorded construction year, grouped by decade
Built before 1900
2 bridges
1910–1919
2 bridges
1920–1929
22 bridges
1930–1939
13 bridges
1940–1949
10 bridges
1950–1959
13 bridges
1960–1969
188 bridges
1970–1979
71 bridges
1980–1989
39 bridges
1990–1999
38 bridges
2000–2009
104 bridges
2010–2019
14 bridges
2020–2029
7 bridges
What this shows Construction peaked in the 1960s, when 188 of the county's bridges still in the inventory were built, which is 35.9% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year (1975) matches the Michigan average (1976).
The 5 Michigan counties nearest Kent County in number of bridges, with their condition splits. Its 5.4% Poor share is the 1st-lowest of these 6. Its average build year of 1975 against a peer-group mean of 1979 is in line with the group.
Showing the 5 closest of 82 Michigan counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Kent County (this page) | 523 | 36.9% | 57.7% | 5.4% | 1975 |
| Oakland County | 508 | 41.5% | 51% | 7.5% | 1982 |
| Macomb County | 417 | 42.7% | 49.6% | 7.7% | 1980 |
| Genesee County | 371 | 22.9% | 61.7% | 15.4% | 1968 |
| St. Clair County | 327 | 41.3% | 50.5% | 8.3% | 1985 |
| Saginaw County | 315 | 28.9% | 52.7% | 18.4% | 1979 |
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 Kent County's. Source: FHWA National Bridge Inventory, 2024 release.
Two NBI-derived peer sets for Kent County, both outside Michigan so the neighborhoods are not the same-state size table above.
Nearest county inventories outside MI (523 bridges here).
Nearest mean year-built outside MI (1975 here).
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Over: BLACK CREEK
0.40 MI E OF KELLER AVE, Kent, MI
Over: PLASTER CREEK
GRAND RAPIDS, Kent, MI
Over: ROGUE RIVER
3.0 MI E OF KENT CITY, Kent, MI
Over: PAGE CREEK
0.6 MI S OF 3 MILE RD, Kent, MI
Over: OTTAWA AVE & RAMP A
IN GRAND RAPIDS, Kent, MI
Over: GRAND RIVER
1000 FT N OF COIT AVE, Kent, MI
Over: E FORK SAND CREEK
0.17 MI N OF 3 MILE ROAD, Kent, MI
Over: CEDAR CREEK
30 FT N OF OAK STREET, Kent, MI
Over: ROGUE RIVER
100 FT E OF RIVER ST, Kent, MI
Over: PLASTER CREEK
GRAND RAPIDS, Kent, MI
Over: GRAND RIVER
475 FT WEST OF MONROE AVE, Kent, MI
Over: US-131BR & IONIA
IN GRAND RAPIDS DIVISION, Kent, MI
Over: PLASTER CREEK
IN WYOMING AND GRAND RAPI, Kent, MI
Over: GRAND RIVER
GRAND RAPIDS, Kent, MI
Over: THORNAPPLE RIVER
0.2 MI W OF WHITNEYVILLE, Kent, MI
Over: ANDERSON COUNTY DRAIN
200 FT E OF HANNA LAKE, Kent, MI
Over: NASH CREEK
0.23 MI N OF DIVISION ST, Kent, MI
Over: DIVISION AVE
IN GRAND RAPIDS, Kent, MI
Over: BEAR CREEK
0.20 MI SOUTH OF 6 MI RD, Kent, MI
Over: UNNAMED CREEK
0.10 MI N OF HAYES, Kent, MI
Over: CEDAR CREEK
0.25 MI N OF 14 MILE RD, Kent, MI
Over: THORNAPPLE RIVER
0.80 MI E OF BURGER DRIVE, Kent, MI
Over: ROGUE RIVER
0.20 MI E OF AFTON AVE, Kent, MI
Over: I-96 WB TO 36TH SB CONN
CASCADE TWP, Kent, MI
Over: WETLANDS WILDLIFE PATH
CASCADE TWP, Kent, MI
Over: PLASTER CREEK
450 FT EAST OF CLYDE PARK, Kent, MI
Over: INDIAN MILL CREEK
0.2 MI SOUTH OF ANN ST, Kent, MI
Over: CEDAR CREEK
0.30 MI W OF ALGOMA AVE, Kent, MI
Over: BUCK CREEK
200 FT S OF 44TH ST, Kent, MI
Over: GRAND RIVER
300 FT WEST OF MARKET AVE, Kent, MI
Over: DUKE CREEK
.30 MI W OF CEDAR SPRINGS, Kent, MI
Over: INDIAN MILL CREEK
450 FT SOUTH OF ANN ST, Kent, MI
Over: MILL CREEK
4.0 MI N OF WALKER, Kent, MI
Over: SPRING CREEK
0.90 MI S OF 20 MILE RD, Kent, MI
Over: BUCK CREEK
0.25 MILE S OF 76TH ST, Kent, MI
Over: HONEY CREEK
0.40 MI NW OF HONEY CREEK, Kent, MI
Over: PRATT LAKE DRAIN
200 FT S OF 72ND ST, Kent, MI
Over: UNNAMED
0.35 MI N OF 60TH ST, Kent, MI
Over: GRAND TRUNK RR
GRAND RAPIDS, Kent, MI
Over: NASH CREEK
0.14 MI N OF DIVISION ST, Kent, MI
Over: PLASTER CREEK
GAINES TWP SEC 3, Kent, MI
Over: ANDERSON DRAIN
GAINES TWP SEC 2, Kent, MI
Over: ANDERSON DRAIN
GAINES TWP SEC 2, Kent, MI
Read our methodology - how this data is sourced, computed, and verified.
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.