Total bridges
263
Public highway bridges in Winnebago County
County profile · official public datasets
Winnebago County, WI
263 public highway bridges tracked in the FHWA National Bridge Inventory: 66.9% rated Good, 29.7% Fair, 3.4% Poor.
- 263
- Public bridges
- 66.9%
- Good condition
- 3.4%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Winnebago County pairs a top-quartile lowest Poor-condition share among rated counties in the state with a newer average build year than the state inventory.
- Top 15%
- lowest Poor share in state
- 3.4%
- Poor-condition share
- 263
- public highway bridges
- 1992
- 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.
Winnebago County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Winnebago County ranks #11 of 72 Wisconsin counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 3.4%). Winnebago County, Wisconsin contains 263 public highway bridges. Roughly 66.9% are rated “Good,” 29.7% “Fair,” and 3.4% “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.
Good condition
66.9%
176 of 263 rated 7-9
Fair condition
29.7%
78 of 263 rated 5-6
Poor condition
3.4%
9 of 263 rated 4 or below
In-state Poor-share rank
#11 of 72
Among Wisconsin counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 263 NBI-tracked bridges by lowest applicable component rating.
Good 66.9% (176)
Fair 29.7% (78)
Poor 3.4% (9)
Winnebago County's Poor-condition bridges carry 7,513 vehicle crossings a day
That is 0.2% of the county's reported daily bridge traffic on 3.4% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 835 crossings a day against 11,493 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 263 of 263 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
15.2% of Winnebago County's bridges have passed the 50-year mark
40 of the 263 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 66.9% 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.
One structure carries 83.9% of the county's Poor-condition bridge traffic
LRD NORTHERN ROAD over S BR MUD CREEK, built 1975, carries 6,300 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 9-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 7,513 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Winnebago County's bridges were built
263 bridges with a recorded construction year, grouped by decade
- 1920s 9
1920–1929
9 bridges
- 1930s 8
1930–1939
8 bridges
- 1950s 4
1950–1959
4 bridges
- 1960s 11
1960–1969
11 bridges
- 1970s 29
1970–1979
29 bridges
- 1980s 18
1980–1989
18 bridges
- 1990s
1990–1999
53 bridges
- 2000s
2000–2009
74 bridges
- 2010s
2010–2019
55 bridges
- 2020s 2
2020–2029
2 bridges
What this shows Construction peaked in the 2000s, when 74 of the county's bridges still in the inventory were built, which is 28.1% of those with a recorded year. That cohort is now 15 to 24 years old in the 2024 inventory. Its average build year is 1992, 8 years newer than the Wisconsin average of 1984.
How Winnebago County compares with Wisconsin's closest counties by inventory size
The 5 Wisconsin counties nearest Winnebago County in number of bridges, with their condition splits. Its 3.4% Poor share is the 1st-lowest of these 6. Its average build year of 1992 against a peer-group mean of 1985 is 7 years newer.
Showing the 5 closest of 71 Wisconsin counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Sauk County | 271 | 53.9% | 37.3% | 8.9% | 1984 |
| Manitowoc County | 269 | 44.6% | 51.7% | 3.7% | 1983 |
| Winnebago County (this page) | 263 | 66.9% | 29.7% | 3.4% | 1992 |
| Trempealeau County | 260 | 47.3% | 41.2% | 11.5% | 1987 |
| Fond du Lac County | 251 | 53% | 36.7% | 10.4% | 1986 |
| La Crosse County | 249 | 41% | 53% | 6% | 1983 |
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 Winnebago 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 Winnebago County, both outside Wisconsin so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside WI (263 bridges here).
- Douglas County, CO · 263 bridges
- Bingham County, ID · 263 bridges
- Guthrie County, IA · 263 bridges
- Henry County, MO · 263 bridges
Similar average build year
Nearest mean year-built outside WI (1992 here).
- Johnson County, KS · avg 1992 · 781 bridges
- Wake County, NC · avg 1992 · 760 bridges
- Benton County, AR · avg 1992 · 410 bridges
- Nodaway County, MO · avg 1992 · 396 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Poor-condition bridges (9)
LRD ACCESS RD
PoorOver: MENASHA CHANNEL
ACCESS TO PARKING LOT BY, Winnebago, WI
Built 1960 Load: 1.6 t ADT: 20
LRD QUIGLEY RD
PoorOver: LAKE POYGAN TRIB
0.2M S JCT CTH B, Winnebago, WI
Built 1920 Load: 16.2 t ADT: 40
LRD APACHE AVE
PoorOver: ADLER CREEK
0.9M W JCT CTH H, Winnebago, WI
Built 1927 Load: 19.4 t ADT: 35
LRD W 35TH AVE
PoorOver: MERRITS CREEK
0.3M W JCT CTH I, Winnebago, WI
Built 1980 Load: 19.4 t ADT: 153
LRD ONPRATT TRAIL
PoorOver: LAKE WINNEBAGO
0.1M E JCT PARKWAY AVE, Winnebago, WI
Built 1921 Load: 19.4 t ADT: 115
CTH-FF
PoorOver: EIGHT MILE CREEK
0.5M N JCT STH 44, Winnebago, WI
Built 1954 Load: 21.1 t ADT: 730
LRD WOODENSHOE RD
PoorOver: NEENAH SLOUGH
1.2M S JCT CTH G, Winnebago, WI
Built 1925 Load: 38.9 t ADT: 38
LRD NORTHERN ROAD
PoorOver: S BR MUD CREEK
0.2M S JCT CTH BB, Winnebago, WI
Built 1975 Load: 40.5 t ADT: 6,300
LRD 9TH ST RD
PoorOver: SPRING BROOK
1.0M W JCT CTH FF, Winnebago, WI
Built 1932 Load: 40.5 t ADT: 82
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.