Total bridges
271
Public highway bridges in Sauk County
County profile · official public datasets
Sauk County, WI
271 public highway bridges tracked in the FHWA National Bridge Inventory: 53.9% rated Good, 37.3% Fair, 8.9% Poor.
- 271
- Public bridges
- 53.9%
- Good condition
- 8.9%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Sauk County posts a higher-than-median Poor-condition share among rated counties in the state across mid-size county bridge inventory.
- 54th
- of 72 on Poor share
- 8.9%
- Poor-condition share
- 271
- public highway bridges
- 1984
- 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.
Sauk County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Sauk County ranks #54 of 72 Wisconsin counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 8.9%). Sauk County, Wisconsin contains 271 public highway bridges. Roughly 53.9% are rated “Good,” 37.3% “Fair,” and 8.9% “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.
Good condition
53.9%
146 of 271 rated 7-9
Fair condition
37.3%
101 of 271 rated 5-6
Poor condition
8.9%
24 of 271 rated 4 or below
In-state Poor-share rank
#54 of 72
Among Wisconsin counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 271 NBI-tracked bridges by lowest applicable component rating.
Good 53.9% (146)
Fair 37.3% (101)
Poor 8.9% (24)
Sauk County's Poor-condition bridges carry 8,116 vehicle crossings a day
That is 0.9% of the county's reported daily bridge traffic on 8.9% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 338 crossings a day against 2,831 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 271 of 271 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
31.4% of Sauk County's bridges have passed the 50-year mark
85 of the 271 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 53.9% 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 18.5% of the county's Poor-condition bridge traffic
CTH B MAIN ST over BR HONEY CREEK, built 1969, carries 1,500 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 24-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 8,116 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Sauk County's bridges were built
271 bridges with a recorded construction year, grouped by decade
- pre-1900 2
Built before 1900
2 bridges
- 1910s 1
1910–1919
1 bridges
- 1920s 5
1920–1929
5 bridges
- 1930s 12
1930–1939
12 bridges
- 1940s 8
1940–1949
8 bridges
- 1950s 14
1950–1959
14 bridges
- 1960s
1960–1969
33 bridges
- 1970s
1970–1979
23 bridges
- 1980s
1980–1989
38 bridges
- 1990s
1990–1999
48 bridges
- 2000s
2000–2009
46 bridges
- 2010s
2010–2019
37 bridges
- 2020s 4
2020–2029
4 bridges
What this shows Construction peaked in the 1990s, when 48 of the county's bridges still in the inventory were built, which is 17.7% of those with a recorded year. That cohort is now 25 to 34 years old in the 2024 inventory. Its average build year (1984) matches the Wisconsin average (1984).
How Sauk County compares with Wisconsin's closest counties by inventory size
The 5 Wisconsin counties nearest Sauk County in number of bridges, with their condition splits. Its 8.9% Poor share is the 4th-lowest of these 6. Its average build year of 1984 against a peer-group mean of 1986 is in line with the group.
Showing the 5 closest of 71 Wisconsin counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Outagamie County | 290 | 49.7% | 46.2% | 4.1% | 1982 |
| Sauk County (this page) | 271 | 53.9% | 37.3% | 8.9% | 1984 |
| Manitowoc County | 269 | 44.6% | 51.7% | 3.7% | 1983 |
| Winnebago County | 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 |
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 Sauk 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 Sauk County, both outside Wisconsin so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside WI (271 bridges here).
- Morgan County, AL · 271 bridges
- Yolo County, CA · 271 bridges
- Yazoo County, MS · 271 bridges
- Hall County, NE · 271 bridges
Similar average build year
Nearest mean year-built outside WI (1984 here).
- Hennepin County, MN · avg 1984 · 936 bridges
- Duval County, FL · avg 1984 · 831 bridges
- El Paso County, CO · avg 1984 · 686 bridges
- Bell County, TX · avg 1984 · 660 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Fair-condition bridges (101)
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.