County profile · official public datasets

Marion County, IL

296 public highway bridges tracked in the FHWA National Bridge Inventory: 62.5% rated Good, 31.1% Fair, 6.4% Poor.

296
Public bridges
62.5%
Good condition
6.4%
Poor condition

The verdict

According to the Federal Highway Administration's 2024 National Bridge Inventory.

Marion County pairs a better-than-median Poor-condition share among rated counties in the state with an older average build year than the state inventory.

Top 32%
lowest Poor share in state
6.4%
Poor-condition share
296
public highway bridges
1973
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.

Marion County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Marion County ranks #33 of 102 Illinois counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 6.4%). Marion County, Illinois contains 296 public highway bridges. Roughly 62.5% are rated “Good,” 31.1% “Fair,” and 6.4% “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.

Total bridges

296

Public highway bridges in Marion County

Good condition

62.5%

185 of 296 rated 7-9

Fair condition

31.1%

92 of 296 rated 5-6

Poor condition

6.4%

19 of 296 rated 4 or below

In-state Poor-share rank

#33 of 102

Among Illinois counties with 5+ bridges, lower share ranks better

Condition distribution

Share of 296 NBI-tracked bridges by lowest applicable component rating.

Good
62.5% (185)
Fair
31.1% (92)
Poor
6.4% (19)

Marion County's Poor-condition bridges carry 8,285 vehicle crossings a day

That is 1.7% of the county's reported daily bridge traffic on 6.4% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 436 crossings a day against 1,404 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 295 of 296 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

44.3% of Marion County's bridges have passed the 50-year mark

131 of the 296 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 62.5% 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 47.1% of the county's Poor-condition bridge traffic

IL 161 - FAP 805 over FAI-57, built 1968, carries 3,900 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 19-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 8,285 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

When Marion County's bridges were built

296 bridges with a recorded construction year, grouped by decade

bridges

What this shows Construction peaked in the 1980s, when 52 of the county's bridges still in the inventory were built, which is 17.6% of those with a recorded year. That cohort is now 35 to 44 years old in the 2024 inventory. Its average build year is 1973, 6 years older than the Illinois average of 1979.

Source FHWA National Bridge Inventory (year built) As of 2024 NBI release

How Marion County compares with Illinois's closest counties by inventory size

The 5 Illinois counties nearest Marion County in number of bridges, with their condition splits. Its 6.4% Poor share is the 2nd-lowest of these 6. Its average build year of 1973 against a peer-group mean of 1980 is 7 years older.

Showing the 5 closest of 101 Illinois counties eligible for comparison.

Bridge inventory size and condition shares for Marion County and the 5 Illinois counties closest to it in inventory size
County Bridges Poor
Coles County 304 8.9%
Knox County 304 11.2%
Ford County 302 6.3%
Marion County (this page) 296 6.4%
Hancock County 292 20.2%
Logan County 292 8.2%

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 Marion 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 Marion County, both outside Illinois so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside IL (296 bridges here).

Similar average build year

Nearest mean year-built outside IL (1973 here).

Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.

All 296 Good 185 Fair 92 Poor 19

Good-condition bridges (185)

TR-498A (Sullens R

Good

Over: Conner Branch

3 Mi E of Iuka, Marion, IL

Built 1900 Load: 8.4 t ADT: 25

TR-309

Good

Over: TURKEY CREEK

1 MI NE CENTRAL CITY, Marion, IL

Built 1984 Load: 8.7 t ADT: 425

FAS-790

Good

Over: WILLS CREEK

4 MI W ALMA, Marion, IL

Built 1938 Load: 13.9 t ADT: 175

CH-20

Good

Over: N END SALEM RESERV0I

1.5 MI N SALEM, Marion, IL

Built 1953 Load: 17.5 t ADT: 700

TR-216

Good

Over: VERMILION CREEK

1.5 MI SW SALEM, Marion, IL

Built 1909 Load: 19.4 t ADT: 1,150

TR-403

Good

Over: RACCOON CREEK

3 MI E CENTRALIA, Marion, IL

Built 1909 Load: 19.4 t ADT: 125

CH 27

Good

Over: CREEK

2 MI SE KINMUNDY, Marion, IL

Built 1952 Load: 22.7 t ADT: 175

TR-401A

Good

Over: SCHWARTZ BRANCH

1.5 MI E CENTRALIA, Marion, IL

Built 1909 Load: 24.3 t ADT: 275

FAS-2789

Good

Over: SKILLET FORK

4 MI E OMEGA, Marion, IL

Built 1975 Load: 24.3 t ADT: 75

FAS 789

Good

Over: PAINTROCK CREEK

6 MI S IUKA, Marion, IL

Built 1948 Load: 24.3 t ADT: 725

FAS 795

Good

Over: PAINTROCK CREEK

6 MI S IUKA, Marion, IL

Built 1909 Load: 24.3 t ADT: 1,000

OR-6125 (PUB PRK R

Good

Over: SPILLWAY

STEPHEN FORBES ST PK, Marion, IL

Built 1963 Load: 24.3 t ADT: 50

BOONE ST RD (TR 19

Good

Over: FAI-57

1 MI N SALEM INT, Marion, IL

Built 1968 Load: 25.3 t ADT: 1,700

FAS-791

Good

Over: BRANCH CROOKED CREEK

3 MI S SELMAVILLE, Marion, IL

Built 1940 Load: 25.9 t ADT: 2,500

FAS-1787

Good

Over: DAVIDSON CREEK

2 MI W TONTI, Marion, IL

Built 1940 Load: 25.9 t ADT: 525

TR-116

Good

Over: PRAIRIE CREEK

1 MI N ODIN, Marion, IL

Built 1979 Load: 25.9 t ADT: 150

NATION RD (CH 36)

Good

Over: FAI-57

3.5 MI S SALEM INT, Marion, IL

Built 1968 Load: 27.2 t ADT: 375

OAK GROVE RD (CH 1

Good

Over: FAI-57

3 MI S PATOKA INT, Marion, IL

Built 1968 Load: 27.2 t ADT: 200

ROBB ROAD (TR 45)

Good

Over: FAI-57

2 MI N PATOKA INT, Marion, IL

Built 1969 Load: 27.2 t ADT: 250

ST PETER RD(FAS279

Good

Over: FAI-57

2.75 MI S FAYETTE CL, Marion, IL

Built 1969 Load: 27.9 t ADT: 500

BLOMBERG RD (TR396

Good

Over: FAI-57

1.5 MI S FAYETTE C L, Marion, IL

Built 1969 Load: 27.9 t ADT: 125

TR-150

Good

Over: CROOKED CREEK

1 MI NW LAKE CENTRAL, Marion, IL

Built 1978 Load: 27.9 t ADT: 100

US 51 (FAP 322)

Good

Over: LOST CREEK

1.8 MI N SANDOVAL, Marion, IL

Built 1959 Load: 28.2 t ADT: 3,150

FAS-2789

Good

Over: DUMS CREEK

2 MI E BRUBAKER, Marion, IL

Built 1971 Load: 28.2 t ADT: 225

IL 161WB (McCord S

Good

Over: 3 streets BNSFRR ATK ICR

Centralia, Marion, IL

Built 1986 Load: 28.8 t ADT: 8,200

TR-65

Good

Over: CREEK

1.2 MI W KINMUNDY, Marion, IL

Built 1969 Load: 28.8 t ADT: 25

TR-1

Good

Over: LEE CREEK

1 MI N VERNON, Marion, IL

Built 1981 Load: 29.2 t ADT: 75

FAI-57

Good

Over: S TRIB E BR KASK RVR

E OF KINMUNDY, Marion, IL

Built 1969 Load: 29.8 t ADT: 18,100

LEVEE ROAD (TR 341

Good

Over: FAI-57

2 MI N ILL 161 INT, Marion, IL

Built 1968 Load: 30.1 t ADT: 175

TR-335A

Good

Over: NICKOLSON CREEK

7 MI SE IUKA, Marion, IL

Built 1978 Load: 30.5 t ADT: 50

US 51 (FAP 322)

Good

Over: DEER CREEK

4.2 MI S FAYETTE C L, Marion, IL

Built 1959 Load: 31.8 t ADT: 2,500

FAS-2719 (CH-8)

Good

Over: E FK KASKASKIA RIVER

2 MI NW ALMA, Marion, IL

Built 1986 Load: 31.8 t ADT: 800

OLD US 51 (SBI 2)

Good

Over: DEER CREEK

NCL PATOKA, Marion, IL

Built 2001 Load: 32.4 t ADT: 450

CH-33

Good

Over: TURKEY RUN

2 MI SE SANDOVAL, Marion, IL

Built 1909 Load: 32.4 t ADT: 625

TR-249

Good

Over: FULKS CREEK

S PART SALEM, Marion, IL

Built 1966 Load: 32.4 t ADT: 1,300

CH 20 Bee Branch R

Good

Over: Dums Creek

4 Mi SE of Alma, Marion, IL

Built 2016 Load: 32.4 t ADT: 275

TR-262

Good

Over: NORTH FORK

8 MI E VERNON, Marion, IL

Built 1973 Load: 32.4 t ADT: 25

FAS-2719 (CH-8)

Good

Over: EAST FORK SLOUGH

2 MI NE ALMA, Marion, IL

Built 1986 Load: 32.4 t ADT: 800

CH-20

Good

Over: DAVIDSON CREEK

W EDGE TONTI, Marion, IL

Built 1989 Load: 32.4 t ADT: 425

CH-20

Good

Over: CREEK

1 MI N SALEM, Marion, IL

Built 1989 Load: 32.4 t ADT: 500

CH-27

Good

Over: TRIB SCHNIEDER BR

2 MI NE KINMUNDY, Marion, IL

Built 1989 Load: 32.4 t ADT: 175

CH-34

Good

Over: NORTH FORK CREEK

2 MI E VERNON, Marion, IL

Built 1990 Load: 32.4 t ADT: 150

CH-19

Good

Over: BRUBAKER CREEK

2 MI SE SALEM, Marion, IL

Built 1994 Load: 32.4 t ADT: 575

TR-148

Good

Over: RACCOON CREEK

1.3 MI NE WALNUT HIL, Marion, IL

Built 1994 Load: 32.4 t ADT: 150

TR-396

Good

Over: KASKASKIA RIVER

2 MI NE KINMUNDY, Marion, IL

Built 1994 Load: 32.4 t ADT: 125

TR-222

Good

Over: TRIB CROOKED CREEK

4.5 MI S SALEM, Marion, IL

Built 1994 Load: 32.4 t ADT: 10

TR-100

Good

Over: SCHWARTZ BRANCH

2 MI NNW WALNUT HILL, Marion, IL

Built 1995 Load: 32.4 t ADT: 350

TR 25

Good

Over: CROOKED CREEK

5 MI NE OF KINMUNDY, Marion, IL

Built 1996 Load: 32.4 t ADT: 200

TR 468

Good

Over: LICK BRANCH

8.5 MI SE OF KELL, Marion, IL

Built 1996 Load: 32.4 t ADT: 25

FAS 790

Good

Over: DAVIDSON CREEK

5 MI N SANDOVAL, Marion, IL

Built 1997 Load: 32.4 t ADT: 350

Read our methodology - how this data is sourced, computed, and verified.

Related

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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.