County profile · official public datasets

Marinette County, WI

135 public highway bridges tracked in the FHWA National Bridge Inventory: 57.8% rated Good, 36.3% Fair, 5.9% Poor.

135
Public bridges: 57.8%
Good condition: 5.9%
Poor condition

The verdict

According to the Federal Highway Administration's 2024 National Bridge Inventory.

Marinette County posts a better-than-median Poor-condition share among rated counties in the state across mid-size county bridge inventory.

Top 49%
lowest Poor share in state: 5.9%
Poor-condition share: 135
public highway bridges: 1986
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.

Marinette County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Marinette County ranks #35 of 72 Wisconsin counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 5.9%). Marinette County, Wisconsin contains 135 public highway bridges. Roughly 57.8% are rated “Good,” 36.3% “Fair,” and 5.9% “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

135

Public highway bridges in Marinette County

Good condition

57.8%

78 of 135 rated 7-9

Fair condition

36.3%

49 of 135 rated 5-6

Poor condition

5.9%

8 of 135 rated 4 or below

In-state Poor-share rank

#35 of 72

Among Wisconsin counties with 5+ bridges, lower share ranks better

Condition distribution

Share of 135 NBI-tracked bridges by lowest applicable component rating.

Good

57.8% (78)

Fair

36.3% (49)

Poor

5.9% (8)

Marinette County's Poor-condition bridges carry 5,323 vehicle crossings a day

That is 1.7% of the county's reported daily bridge traffic on 5.9% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 665 crossings a day against 3,173 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 135 of 135 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

25.9% of Marinette County's bridges have passed the 50-year mark

35 of the 135 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 57.8% 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 31.9% of the county's Poor-condition bridge traffic

CTH W over LITTLE PESHTIGO RIVER, built 1920, carries 1,700 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 8-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 5,323 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1920s

6
1930s

3
1940s

1
1950s

6
1960s

12
1970s

12
1980s

17
1990s

39
2000s

31
2010s

5
2020s

3

What this shows Construction peaked in the 1990s, when 39 of the county's bridges still in the inventory were built, which is 28.9% of those with a recorded year. That cohort is now 25 to 34 years old in the 2024 inventory. Its average build year (1986) matches the Wisconsin average (1984).

How Marinette County compares with Wisconsin's closest counties by inventory size

The 5 Wisconsin counties nearest Marinette County in number of bridges, with their condition splits. Its 5.9% Poor share is the 2nd-lowest of these 6. Its average build year of 1986 against a peer-group mean of 1986 is in line with the group.

Showing the 5 closest of 71 Wisconsin counties eligible for comparison.

Bridge inventory size and condition shares for Marinette County and the 5 Wisconsin counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Lincoln County	157	49%	44.6%	6.4%	1982
Rusk County	151	49.7%	44.4%	6%	1989
Oconto County	149	55.7%	40.9%	3.4%	1986
Douglas County	135	51.1%	36.3%	12.6%	1984
Marinette County (this page)	135	57.8%	36.3%	5.9%	1986
Racine County	133	58.6%	31.6%	9.8%	1991

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 Marinette 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 Marinette County, both outside Wisconsin so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside WI (135 bridges here).

Nevada County, CA · 135 bridges
Meriwether County, GA · 135 bridges
Steuben County, IN · 135 bridges
Warren County, IN · 135 bridges

Similar average build year

Nearest mean year-built outside WI (1986 here).

El Paso County, TX · avg 1986 · 783 bridges
Caddo County, LA · avg 1986 · 682 bridges
Weld County, CO · avg 1986 · 614 bridges
Polk County, IA · avg 1986 · 545 bridges

Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.

All 135 Good 78 Fair 49 Poor 8

Good-condition bridges (78)

Sort:

Marinette County Bridge Snapshot

Condition distribution

Marinette County's Poor-condition bridges carry 5,323 vehicle crossings a day

25.9% of Marinette County's bridges have passed the 50-year mark

One structure carries 31.9% of the county's Poor-condition bridge traffic

How Marinette County compares with Wisconsin's closest counties by inventory size

Nationwide counties with similar inventory size or average build year

Similar inventory size

Similar average build year

Good-condition bridges (78)

LRD HIGH FALLS ROA

LRD DOW DAM RD

LRD MORGAN PARK RD

USH 8

LRD TOWN CORNER LA

CTH Q

USH 8-USH 141

STH 180

USH 41

LRD DAM RD (DEAD E

LRD JAMROS RD

LRD MCMAHON RD

LRD SMITH CREEK RD

LRD THIRD ROAD

CTH O

CTH CP (BUSINESS 1

CTH R

LRD TWIN LAKES RD

CTH W

LRD NOQUEBAY RD

LRD OLD COUNTY A

USH 141

USH 141

LRD E BARKER RD

LRD SWEDE JOHN RD

LRD N 7TH RD (DEAD

USH 141-MAIN ST

LRD N 1ST RD

LRD N 5TH RD (DEAD

LRD FRENCH ST

LRD TOWER HILL RD

STH 64

USH 141

LRD HARPER RD

LRD PIKE RIVER RD

LRD 19TH RD

CTH B S COLEMAN C

CTH CP

USH 141 NB

CTH BB

LRD 11TH RD

LRD FORBES RD

LRD LILY LAKE RD

LRD PIKE RIVER DR

LRD SAND RD

USH 8

USH 8

LRD CCC CAMP ROAD

USH 41 NB

USH 41 NB

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