Total bridges
417
Public highway bridges in St. Charles County
County profile · official public datasets
St. Charles County, MO
417 public highway bridges tracked in the FHWA National Bridge Inventory: 32.4% rated Good, 64.3% Fair, 3.4% Poor.
- 417
- Public bridges
- 32.4%
- Good condition
- 3.4%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
St. Charles County pairs a top-5% lowest Poor-condition share among rated counties in the state with a newer average build year than the state inventory.
- Top 5%
- lowest Poor share in state
- 3.4%
- Poor-condition share
- 417
- public highway bridges
- 1994
- 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.
St. Charles County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, St. Charles County ranks #6 of 115 Missouri counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 3.4%). St. Charles County, Missouri contains 417 public highway bridges. Roughly 32.4% are rated “Good,” 64.3% “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
32.4%
135 of 417 rated 7-9
Fair condition
64.3%
268 of 417 rated 5-6
Poor condition
3.4%
14 of 417 rated 4 or below
In-state Poor-share rank
#6 of 115
Among Missouri counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 417 NBI-tracked bridges by lowest applicable component rating.
Good 32.4% (135)
Fair 64.3% (268)
Poor 3.4% (14)
St. Charles County's Poor-condition bridges carry 60,988 vehicle crossings a day
That is 1.1% 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 4,356 crossings a day against 11,038 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 417 of 417 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
14.9% of St. Charles County's bridges have passed the 50-year mark
62 of the 417 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 32.4% 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 64.2% of the county's Poor-condition bridge traffic
IS 64 W over IS 70, built 1971, carries 39,184 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 14-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 60,988 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When St. Charles County's bridges were built
417 bridges with a recorded construction year, grouped by decade
- 1900s 5
1900–1909
5 bridges
- 1930s 7
1930–1939
7 bridges
- 1940s 6
1940–1949
6 bridges
- 1950s 13
1950–1959
13 bridges
- 1960s 18
1960–1969
18 bridges
- 1970s 21
1970–1979
21 bridges
- 1980s 39
1980–1989
39 bridges
- 1990s
1990–1999
103 bridges
- 2000s
2000–2009
119 bridges
- 2010s
2010–2019
75 bridges
- 2020s 11
2020–2029
11 bridges
What this shows Construction peaked in the 2000s, when 119 of the county's bridges still in the inventory were built, which is 28.5% of those with a recorded year. That cohort is now 15 to 24 years old in the 2024 inventory. Its average build year is 1994, 15 years newer than the Missouri average of 1979.
How St. Charles County compares with Missouri's closest counties by inventory size
The 5 Missouri counties nearest St. Charles 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 1994 against a peer-group mean of 1983 is 11 years newer.
Showing the 5 closest of 114 Missouri counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Clay County | 436 | 38.1% | 55% | 6.9% | 1979 |
| Stoddard County | 434 | 43.1% | 53.2% | 3.7% | 1976 |
| St. Charles County (this page) | 417 | 32.4% | 64.3% | 3.4% | 1994 |
| Jefferson County | 411 | 33.6% | 63% | 3.4% | 1981 |
| Vernon County | 401 | 35.4% | 60.3% | 4.2% | 1988 |
| Nodaway County | 396 | 48% | 37.6% | 14.4% | 1992 |
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 St. Charles 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 St. Charles County, both outside Missouri so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside MO (417 bridges here).
- Macomb County, MI · 417 bridges
- Bedford County, PA · 417 bridges
- Santa Barbara County, CA · 418 bridges
- Lucas County, OH · 418 bridges
Similar average build year
Nearest mean year-built outside MO (1994 here).
- Denton County, TX · avg 1994 · 991 bridges
- Rock County, WI · avg 1994 · 304 bridges
- Pitt County, NC · avg 1994 · 228 bridges
- Columbus County, NC · avg 1994 · 226 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
All bridges (417)
PEINE RD S
GoodOver: DRY BRANCH CR
S 413 T 47 N R 1 E, St. Charles, MO
Built 2018 Load: 64.8 t ADT: 8,430
PERUQUE CR RD
GoodOver: PERUQUE CR
S 34 T 48 N R 3 E, St. Charles, MO
Built 2002 Load: 72.0 t ADT: 150
SIBLEY SST
GoodOver: BOSCHERT CR
S 2892 T 47 N R 5 E, St. Charles, MO
Built 2019 Load: 80.1 t ADT: 3,100
PARK RD C
PoorOver: BR OF DARDENNE CR
S 280 T 46 N R 2 E, St. Charles, MO
Built 1942 Load: 16.2 t ADT: 1,000
PARK RD B
PoorOver: BR OF DARDENNE CR
S 887 T 46 N R 2 E, St. Charles, MO
Built 1942 Load: 16.2 t ADT: 1,000
JOSEPHVILLE RD
PoorOver: TRIB OF CUIVRE RVR
S 9 T 47 N R 2 E, St. Charles, MO
Built 1950 Load: 20.7 t ADT: 977
FEMME OSAGE CR RD
PoorOver: TRIB OF FEMME OSAG
S 1792 T 45 N R 1 E, St. Charles, MO
Built 1900 Load: 27.0 t ADT: 306
OR 64 E
PoorOver: PERUQUE CR
S 33 T 47 N R 2 E, St. Charles, MO
Built 1935 Load: 27.9 t ADT: 2,603
AUGUSTA BOTTOM RD
PoorOver: TRIB OF MISSOURI R
S 18 T 44 N R 1 E, St. Charles, MO
Built 1970 Load: 32.4 t ADT: 363
DIETRICH RD
PoorOver: TRIB OF MCCOY CR
S 18 T 47 N R 1 E, St. Charles, MO
Built 1987 Load: 32.4 t ADT: 2,429
RT W S
PoorOver: IS 70
S 19 T 47 N R 1 E, St. Charles, MO
Built 1963 Load: 32.4 t ADT: 10,399
IS 64 W
PoorOver: IS 70
S 30 T 47 N R 2 E, St. Charles, MO
Built 1971 Load: 36.0 t ADT: 39,184
SNEAK RD
PoorOver: CALLAWAY FK OSAGE
S 31 T 46 N R 1 E, St. Charles, MO
Built 1989 Load: 44.1 t ADT: 121
SCHWEDE RD
PoorOver: TRIB OF DARDENNE C
S 20 T 46 N R 2 E, St. Charles, MO
Built 1988 Load: 45.0 t ADT: 472
HOWELL RD
PoorOver: FEMME OSAGE CR
S 970 T 45 N R 2 E, St. Charles, MO
Built 1991 Load: 45.9 t ADT: 59
OBERHELMAN RD
PoorOver: TRIB OF DARDENNE C
S 29 T 46 N R 1 E, St. Charles, MO
Built 1986 Load: 54.0 t ADT: 355
ST PAUL RD
PoorOver: TRIB OF PERUQUE CR
S 1 T 47 N R 2 E, St. Charles, MO
Built 1940 Load: 57.6 t ADT: 1,720
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.