Total bridges
187
Public highway bridges in Grundy County
County profile · official public datasets
Grundy County, MO
187 public highway bridges tracked in the FHWA National Bridge Inventory: 54% rated Good, 34.8% Fair, 11.2% Poor.
- 187
- Public bridges
- 54%
- Good condition
- 11.2%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Grundy County pairs a higher-than-median Poor-condition share among rated counties in the state with a newer average build year than the state inventory.
- 83rd
- of 115 on Poor share
- 11.2%
- Poor-condition share
- 187
- 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.
Grundy County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Grundy County ranks #83 of 115 Missouri counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 11.2%). Grundy County, Missouri contains 187 public highway bridges. Roughly 54% are rated “Good,” 34.8% “Fair,” and 11.2% “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
54%
101 of 187 rated 7-9
Fair condition
34.8%
65 of 187 rated 5-6
Poor condition
11.2%
21 of 187 rated 4 or below
In-state Poor-share rank
#83 of 115
Among Missouri counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 187 NBI-tracked bridges by lowest applicable component rating.
Good 54% (101)
Fair 34.8% (65)
Poor 11.2% (21)
Grundy County's Poor-condition bridges carry 957 vehicle crossings a day
That is 1.7% of the county's reported daily bridge traffic on 11.2% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 46 crossings a day against 251 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 187 of 187 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
17.1% of Grundy County's bridges have passed the 50-year mark
32 of the 187 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 54% 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 28.3% of the county's Poor-condition bridge traffic
RT E E over MEDICINE CR DRAIN, built 1947, carries 271 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 21-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 957 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Grundy County's bridges were built
187 bridges with a recorded construction year, grouped by decade
- 1900s 1
1900–1909
1 bridges
- 1910s 1
1910–1919
1 bridges
- 1920s 2
1920–1929
2 bridges
- 1930s 7
1930–1939
7 bridges
- 1940s 5
1940–1949
5 bridges
- 1950s 3
1950–1959
3 bridges
- 1960s 10
1960–1969
10 bridges
- 1970s 4
1970–1979
4 bridges
- 1980s 7
1980–1989
7 bridges
- 1990s
1990–1999
73 bridges
- 2000s
2000–2009
36 bridges
- 2010s 26
2010–2019
26 bridges
- 2020s 12
2020–2029
12 bridges
What this shows Construction peaked in the 1990s, when 73 of the county's bridges still in the inventory were built, which is 39% of those with a recorded year. That cohort is now 25 to 34 years old in the 2024 inventory. Its average build year is 1992, 13 years newer than the Missouri average of 1979.
How Grundy County compares with Missouri's closest counties by inventory size
The 5 Missouri counties nearest Grundy County in number of bridges, with their condition splits. Its 11.2% Poor share is the 5th-lowest of these 6. Its average build year of 1992 against a peer-group mean of 1978 is 14 years newer.
Showing the 5 closest of 114 Missouri counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Howell County | 189 | 34.4% | 63.5% | 2.1% | 1966 |
| Lincoln County | 189 | 40.2% | 56.1% | 3.7% | 1987 |
| Webster County | 189 | 45.5% | 46% | 8.5% | 1981 |
| Grundy County (this page) | 187 | 54% | 34.8% | 11.2% | 1992 |
| Marion County | 186 | 37.1% | 53.8% | 9.1% | 1977 |
| Livingston County | 185 | 34.1% | 50.3% | 15.7% | 1978 |
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 Grundy 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 Grundy County, both outside Missouri so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside MO (187 bridges here).
- Lonoke County, AR · 187 bridges
- Huntington County, IN · 187 bridges
- Henry County, TN · 187 bridges
- Chesapeake city County, VA · 187 bridges
Similar average build year
Nearest mean year-built outside MO (1992 here).
- Johnson County, KS · avg 1992 · 781 bridges
- Wake County, NC · avg 1992 · 760 bridges
- Benton County, AR · avg 1992 · 410 bridges
- Cameron County, TX · avg 1992 · 355 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Good-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.