Total bridges
185
Public highway bridges in Polk County
County profile · official public datasets
Polk County, MO
185 public highway bridges tracked in the FHWA National Bridge Inventory: 31.9% rated Good, 47.6% Fair, 20.5% Poor.
- 185
- Public bridges
- 31.9%
- Good condition
- 20.5%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Polk 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.
- 111th
- of 115 on Poor share
- 20.5%
- Poor-condition share
- 185
- public highway bridges
- 1966
- 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.
Polk County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Polk County ranks #111 of 115 Missouri counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 20.5%). Polk County, Missouri contains 185 public highway bridges. Roughly 31.9% are rated “Good,” 47.6% “Fair,” and 20.5% “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
31.9%
59 of 185 rated 7-9
Fair condition
47.6%
88 of 185 rated 5-6
Poor condition
20.5%
38 of 185 rated 4 or below
In-state Poor-share rank
#111 of 115
Among Missouri counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 185 NBI-tracked bridges by lowest applicable component rating.
Good 31.9% (59)
Fair 47.6% (88)
Poor 20.5% (38)
Polk County's Poor-condition bridges carry 30,556 vehicle crossings a day
That is 11.5% of the county's reported daily bridge traffic on 20.5% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 804 crossings a day against 921 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 185 of 185 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
51.9% of Polk County's bridges have passed the 50-year mark
96 of the 185 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 31.9% 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 32.2% of the county's Poor-condition bridge traffic
MO 13 N over DRY SAC RVR, built 1970, carries 9,847 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 38-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 30,556 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Polk County's bridges were built
185 bridges with a recorded construction year, grouped by decade
- 1900s
1900–1909
38 bridges
- 1910s 1
1910–1919
1 bridges
- 1920s 12
1920–1929
12 bridges
- 1930s 5
1930–1939
5 bridges
- 1940s 8
1940–1949
8 bridges
- 1950s 12
1950–1959
12 bridges
- 1960s 12
1960–1969
12 bridges
- 1970s 10
1970–1979
10 bridges
- 1980s 4
1980–1989
4 bridges
- 1990s
1990–1999
16 bridges
- 2000s
2000–2009
33 bridges
- 2010s
2010–2019
25 bridges
- 2020s 9
2020–2029
9 bridges
What this shows Construction peaked in the 1900s, when 38 of the county's bridges still in the inventory were built, which is 20.5% of those with a recorded year. That cohort is now 115 to 124 years old in the 2024 inventory. Its average build year is 1966, 13 years older than the Missouri average of 1979.
How Polk County compares with Missouri's closest counties by inventory size
The 5 Missouri counties nearest Polk County in number of bridges, with their condition splits. Its 20.5% Poor share is the 6th-lowest of these 6. Its average build year of 1966 against a peer-group mean of 1980 is 14 years older.
Showing the 5 closest of 114 Missouri counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Grundy County | 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 |
| Ray County | 185 | 36.2% | 51.4% | 12.4% | 1977 |
| Polk County (this page) | 185 | 31.9% | 47.6% | 20.5% | 1966 |
| Scott County | 182 | 39.6% | 53.8% | 6.6% | 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 Polk 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 Polk County, both outside Missouri so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside MO (185 bridges here).
- Chambers County, AL · 185 bridges
- Maui County, HI · 185 bridges
- Lawrence County, IL · 185 bridges
- Saline County, IL · 185 bridges
Similar average build year
Nearest mean year-built outside MO (1966 here).
- Butler County, KS · avg 1966 · 591 bridges
- Grafton County, NH · avg 1966 · 544 bridges
- Queens County, NY · avg 1966 · 514 bridges
- Lehigh County, PA · avg 1966 · 381 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Fair-condition bridges (88)
COUNTY RD E-475
FairOver: POMME DE TERRE RVR
S 26 T 33 N R 22 W, Polk, MO
Built 1928 Load: 32.4 t ADT: 125
MO 83 S
FairOver: ABELS BR
S 22 T 34 N R 23 W, Polk, MO
Built 1972 Load: 32.4 t ADT: 2,268
COUNTY RD E-530
FairOver: BR POMME DE TERRE
S 21 T 32 N R 21 W, Polk, MO
Built 1900 Load: 32.4 t ADT: 30
COUNTY RD S-111
FairOver: LIT SAC RVR
S 2 T 31 N R 23 W, Polk, MO
Built 1991 Load: 32.4 t ADT: 150
EAST 360TH RD
FairOver: PANTHER CR
S 33 T 35 N R 21 W, Polk, MO
Built 2015 Load: 32.4 t ADT: 50
CRD E 330
FairOver: BR OF BRUSH CR
S 22 T 35 N R 23 W, Polk, MO
Built 2019 Load: 32.4 t ADT: 20
MO 32 E
FairOver: ERVIN CR
S 1 T 33 N R 24 W, Polk, MO
Built 1925 Load: 33.3 t ADT: 5,690
COUNTY RD E-365
FairOver: PANTHER CR
S 1 T 34 N R 22 W, Polk, MO
Built 2000 Load: 34.2 t ADT: 50
COUNTY RD S-62
FairOver: WALNUT CR
S 12 T 32 N R 24 W, Polk, MO
Built 1999 Load: 34.2 t ADT: 50
S-225
FairOver: BR OF BRUSH CR
S 10 T 34 N R 21 W, Polk, MO
Built 2022 Load: 34.2 t ADT: 30
MO 32 E
FairOver: POMME DE TERRE RVR
S 11 T 33 N R 22 W, Polk, MO
Built 1991 Load: 34.2 t ADT: 5,225
MO 83 S
FairOver: MILE CR
S 35 T 34 N R 23 W, Polk, MO
Built 1948 Load: 34.2 t ADT: 4,308
GRANT RD
FairOver: SLAGLE CR
S 13 T 32 N R 23 W, Polk, MO
Built 2012 Load: 35.1 t ADT: 30
MO 32 E
FairOver: HOMINY CR
S 3 T 33 N R 21 W, Polk, MO
Built 1986 Load: 36.0 t ADT: 3,729
MO 83 S
FairOver: MO 13
S 24 T 33 N R 23 W, Polk, MO
Built 2003 Load: 36.9 t ADT: 11,254
RT A E
FairOver: SPRING CR
S 8 T 34 N R 24 W, Polk, MO
Built 1962 Load: 39.6 t ADT: 106
COUNTY RD E-325
FairOver: WILCONSON BR
S 14 T 35 N R 21 W, Polk, MO
Built 2000 Load: 40.5 t ADT: 50
RT P S
FairOver: LINDLEY CR
S 4 T 34 N R 21 W, Polk, MO
Built 1985 Load: 40.5 t ADT: 172
MO 123 S
FairOver: CAMPBELL BR
S 16 T 34 N R 24 W, Polk, MO
Built 1926 Load: 40.5 t ADT: 749
RT N E
FairOver: BRUSH CR
S 16 T 35 N R 24 W, Polk, MO
Built 2004 Load: 41.4 t ADT: 1,143
MO 13 S
FairOver: DRY SAC RVR
S 9 T 31 N R 22 W, Polk, MO
Built 1972 Load: 42.3 t ADT: 9,713
MO 32 E
FairOver: PIPERS CR
S 8 T 33 N R 22 W, Polk, MO
Built 1991 Load: 42.3 t ADT: 5,225
MO 13 S
FairOver: BR OF BRUSH CR
S 3 T 34 N R 24 W, Polk, MO
Built 1958 Load: 43.2 t ADT: 14,528
COUNTY RD E 523
FairOver: SYCAMORE CR
S 24 T 32 N R 22 W, Polk, MO
Built 2000 Load: 43.2 t ADT: 25
MO 13 S
FairOver: BR DRY FORK CR
S 18 T 34 N R 23 W, Polk, MO
Built 1958 Load: 43.2 t ADT: 14,528
MO 32 E
FairOver: MO 13
S 3 T 33 N R 23 W, Polk, MO
Built 2002 Load: 44.1 t ADT: 6,824
MO 83 S
FairOver: DRY FORK CR
S 35 T 35 N R 23 W, Polk, MO
Built 1992 Load: 44.1 t ADT: 2,268
MO 123 S
FairOver: BR OF SPRING CK
S 4 T 34 N R 24 W, Polk, MO
Built 1929 Load: 44.1 t ADT: 626
MO 123 S
FairOver: BEAR CR
S 9 T 33 N R 24 W, Polk, MO
Built 1998 Load: 45.0 t ADT: 673
MO 13 S
FairOver: SLAGLE CR
S 8 T 32 N R 22 W, Polk, MO
Built 1973 Load: 52.2 t ADT: 21,848
MO 13 S
FairOver: DRY SAC RVR BR
S 9 T 31 N R 22 W, Polk, MO
Built 1973 Load: 52.2 t ADT: 19,560
RT F N
FairOver: SLAGLE CR
S 8 T 32 N R 22 W, Polk, MO
Built 1932 Load: 53.1 t ADT: 198
CRD E 450
FairOver: BR OF BEAR CR
S 7 T 33 N R 23 W, Polk, MO
Built 2019 Load: 54.0 t ADT: 20
MO 32 E
FairOver: TOWN BR
S 6 T 33 N R 22 W, Polk, MO
Built 1991 Load: 54.9 t ADT: 4,582
E COWDEN ST
FairOver: MILL CR
S 32 T 32 N R 21 W, Polk, MO
Built 2009 Load: 61.2 t ADT: 150
MO 32 E
FairOver: BARREN CR
S 3 T 33 N R 24 W, Polk, MO
Built 1925 Load: 85.5 t ADT: 5,690
MO 13 S
FairOver: TRIB OF BRUSH CR
S 16 T 35 N R 24 W, Polk, MO
Built 2004 Load: 99.9 t ADT: 6,036
COUNTY RD E-525
FairOver: KIP BR OF TURKEY C
S 19 T 32 N R 24 W, Polk, MO
Built 2004 Load: 99.9 t ADT: 40
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.