Total bridges
183
Public highway bridges in Columbia County
County profile · official public datasets
Columbia County, WI
183 public highway bridges tracked in the FHWA National Bridge Inventory: 30.1% rated Good, 63.9% Fair, 6% Poor.
- 183
- Public bridges
- 30.1%
- Good condition
- 6%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Columbia County pairs a higher-than-median Poor-condition share among rated counties in the state with an older average build year than the state inventory.
- 38th
- of 72 on Poor share
- 6%
- Poor-condition share
- 183
- public highway bridges
- 1977
- 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.
Columbia County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Columbia County ranks #38 of 72 Wisconsin counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 6%). Columbia County, Wisconsin contains 183 public highway bridges. Roughly 30.1% are rated “Good,” 63.9% “Fair,” and 6% “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
30.1%
55 of 183 rated 7-9
Fair condition
63.9%
117 of 183 rated 5-6
Poor condition
6%
11 of 183 rated 4 or below
In-state Poor-share rank
#38 of 72
Among Wisconsin counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 183 NBI-tracked bridges by lowest applicable component rating.
Good 30.1% (55)
Fair 63.9% (117)
Poor 6% (11)
Columbia County's Poor-condition bridges carry 2,132 vehicle crossings a day
That is 0.2% of the county's reported daily bridge traffic on 6% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 194 crossings a day against 4,801 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 183 of 183 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
51.9% of Columbia County's bridges have passed the 50-year mark
95 of the 183 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 30.1% 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 23.5% of the county's Poor-condition bridge traffic
CTH CM over FOX RIVER, built 1958, carries 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 11-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 2,132 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Columbia County's bridges were built
183 bridges with a recorded construction year, grouped by decade
- 1900s 2
1900–1909
2 bridges
- 1910s 1
1910–1919
1 bridges
- 1920s 1
1920–1929
1 bridges
- 1930s 7
1930–1939
7 bridges
- 1940s 3
1940–1949
3 bridges
- 1950s 20
1950–1959
20 bridges
- 1960s
1960–1969
55 bridges
- 1970s 16
1970–1979
16 bridges
- 1980s 6
1980–1989
6 bridges
- 1990s
1990–1999
32 bridges
- 2000s 19
2000–2009
19 bridges
- 2010s 13
2010–2019
13 bridges
- 2020s 8
2020–2029
8 bridges
What this shows Construction peaked in the 1960s, when 55 of the county's bridges still in the inventory were built, which is 30.1% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year is 1977, 7 years older than the Wisconsin average of 1984.
How Columbia County compares with Wisconsin's closest counties by inventory size
The 5 Wisconsin counties nearest Columbia County in number of bridges, with their condition splits. Its 6% Poor share is the 5th-lowest of these 6. Its average build year of 1977 against a peer-group mean of 1986 is 9 years older.
Showing the 5 closest of 71 Wisconsin counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Columbia County (this page) | 183 | 30.1% | 63.9% | 6% | 1977 |
| Jefferson County | 182 | 57.1% | 37.4% | 5.5% | 1987 |
| Portage County | 182 | 53.3% | 44% | 2.7% | 1991 |
| Taylor County | 176 | 58.5% | 30.1% | 11.4% | 1988 |
| Juneau County | 172 | 49.4% | 47.7% | 2.9% | 1981 |
| Waupaca County | 169 | 76.3% | 20.7% | 3% | 1984 |
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 Columbia 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 Columbia County, both outside Wisconsin so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside WI (183 bridges here).
- St. Clair County, AL · 183 bridges
- Richmond County, GA · 183 bridges
- Marshall County, IN · 183 bridges
- Appanoose County, IA · 183 bridges
Similar average build year
Nearest mean year-built outside WI (1977 here).
- San Diego County, CA · avg 1977 · 1,632 bridges
- King County, WA · avg 1977 · 1,238 bridges
- Riverside County, CA · avg 1977 · 1,117 bridges
- Shelby County, TN · avg 1977 · 1,077 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Poor-condition bridges (11)
CTH A
PoorOver: UNION PACIFIC RR
1.0M W JCT STH 73, Columbia, WI
Built 1910 Load: 3.2 t ADT: 197
LRD HALL RD
PoorOver: CRAWFISH RIVER
1.3M E JCT CTH A, Columbia, WI
Built 1961 Load: 8.1 t ADT: 56
LRD KOWALD RD
PoorOver: FOX RIVER
1.1M E JCT CTH H, Columbia, WI
Built 1930 Load: 9.7 t ADT: 31
LRD MILL ST
PoorOver: UNION PACIFIC RR
0.1M W JCT STH 60, Columbia, WI
Built 1900 Load: 16.2 t ADT: 79
CTH K
PoorOver: ROBBINS CREEK
2.8M W JCT USH 151, Columbia, WI
Built 1936 Load: 17.8 t ADT: 196
LRD STERK RD
PoorOver: UNION PACIFIC RR
1.1M S JCT CTH E, Columbia, WI
Built 1930 Load: 22.7 t ADT: 67
LRD INGLEHART RD
PoorOver: UNION PACIFIC RR
0.7M N JCT CTH E, Columbia, WI
Built 1930 Load: 32.4 t ADT: 81
LRD HILL RD (DEAD
PoorOver: MID BR DUCK CREEK
1.9M E JCT STH 22, Columbia, WI
Built 1968 Load: 32.4 t ADT: 4
CTH VJ
PoorOver: ROCKY RUN CREEK
0.8M E JCT CTH J, Columbia, WI
Built 1956 Load: 34.0 t ADT: 470
CTH CM
PoorOver: FOX RIVER
0.1M E JCT CTH T, Columbia, WI
Built 1958 Load: 38.9 t ADT: 500
CTH X
PoorOver: BIG SLOUGH
2.6M S JCT CTH AA, Columbia, WI
Built 1958 Load: 45.4 t ADT: 451
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.