Total bridges
346
Public highway bridges in Macon County
County profile · official public datasets
Macon County, IL
346 public highway bridges tracked in the FHWA National Bridge Inventory: 25.7% rated Good, 58.7% Fair, 15.6% Poor.
- 346
- Public bridges
- 25.7%
- Good condition
- 15.6%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Macon 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.
- 93rd
- of 102 on Poor share
- 15.6%
- Poor-condition share
- 346
- public highway bridges
- 1984
- 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.
Macon County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Macon County ranks #93 of 102 Illinois counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 15.6%). Macon County, Illinois contains 346 public highway bridges. Roughly 25.7% are rated “Good,” 58.7% “Fair,” and 15.6% “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
25.7%
89 of 346 rated 7-9
Fair condition
58.7%
203 of 346 rated 5-6
Poor condition
15.6%
54 of 346 rated 4 or below
In-state Poor-share rank
#93 of 102
Among Illinois counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 346 NBI-tracked bridges by lowest applicable component rating.
Good 25.7% (89)
Fair 58.7% (203)
Poor 15.6% (54)
Macon County's Poor-condition bridges carry 81,150 vehicle crossings a day
That is 9.4% of the county's reported daily bridge traffic on 15.6% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 1,503 crossings a day against 1,358 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 346 of 346 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
19.7% of Macon County's bridges have passed the 50-year mark
68 of the 346 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 25.7% 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 25.8% of the county's Poor-condition bridge traffic
US 36(FAP 320) over LAKE SHORE DR(U 7390, built 1954, carries 20,900 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 54-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 81,150 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Macon County's bridges were built
346 bridges with a recorded construction year, grouped by decade
- 1900s 9
1900–1909
9 bridges
- 1920s 7
1920–1929
7 bridges
- 1930s 2
1930–1939
2 bridges
- 1940s 2
1940–1949
2 bridges
- 1950s 7
1950–1959
7 bridges
- 1960s 27
1960–1969
27 bridges
- 1970s
1970–1979
87 bridges
- 1980s
1980–1989
75 bridges
- 1990s
1990–1999
38 bridges
- 2000s
2000–2009
48 bridges
- 2010s 34
2010–2019
34 bridges
- 2020s 10
2020–2029
10 bridges
What this shows Construction peaked in the 1970s, when 87 of the county's bridges still in the inventory were built, which is 25.1% of those with a recorded year. That cohort is now 45 to 54 years old in the 2024 inventory. Its average build year is 1984, 5 years newer than the Illinois average of 1979.
How Macon County compares with Illinois's closest counties by inventory size
The 5 Illinois counties nearest Macon County in number of bridges, with their condition splits. Its 15.6% Poor share is the 5th-lowest of these 6. Its average build year of 1984 against a peer-group mean of 1983 is in line with the group.
Showing the 5 closest of 101 Illinois counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Peoria County | 352 | 24.1% | 57.7% | 18.2% | 1983 |
| Macon County (this page) | 346 | 25.7% | 58.7% | 15.6% | 1984 |
| DuPage County | 344 | 37.5% | 54.4% | 8.1% | 1985 |
| Kankakee County | 344 | 40.1% | 53.5% | 6.4% | 1982 |
| Stephenson County | 342 | 61.1% | 36.3% | 2.6% | 1977 |
| Kane County | 336 | 48.2% | 45.5% | 6.3% | 1986 |
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 Macon 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 Macon County, both outside Illinois so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside IL (346 bridges here).
- Dubuque County, IA · 346 bridges
- Whitman County, WA · 347 bridges
- Navarro County, TX · 345 bridges
- Fillmore County, MN · 348 bridges
Similar average build year
Nearest mean year-built outside IL (1984 here).
- Hennepin County, MN · avg 1984 · 936 bridges
- Duval County, FL · avg 1984 · 831 bridges
- El Paso County, CO · avg 1984 · 686 bridges
- Bell County, TX · avg 1984 · 660 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
All bridges (346)
TR 239(WELLS RD)
FairOver: SAND CREEK
3 MI E 3 MI N MACON, Macon, IL
Built 1968 Load: 16.8 t ADT: 50
TR 234A(ESTHER RD)
FairOver: STREAM
1.8 M SE DECATUR AIR, Macon, IL
Built 1960 Load: 18.8 t ADT: 75
CH 18(SCHOOL RD)
FairOver: STEVENS CREEK
2.1 MI S OF MAROA, Macon, IL
Built 1969 Load: 19.4 t ADT: 200
TR 114C(RILEY RD)
FairOver: WILLOW BRANCH
1.6 MI SE MACON, Macon, IL
Built 1976 Load: 19.4 t ADT: 50
TR 150(GREENSWITCH
FairOver: Spring Creek
2 MI NE FORSYTH, Macon, IL
Built 1974 Load: 20.7 t ADT: 550
TR 45 Kirby Rd
FairOver: STREAM
4 MI S OF ARGENTA, Macon, IL
Built 1962 Load: 20.7 t ADT: 550
TR 30A(STRAWN RD)
FairOver: DRAINAGE DITCH
3.6 MI NW WARRENSBUR, Macon, IL
Built 1972 Load: 23.0 t ADT: 20
TR 73(W STRINGTOWN
FairOver: STREAM
3.25 MI NW NIANTIC, Macon, IL
Built 1963 Load: 23.0 t ADT: 25
TR 52A(BOODY RD)
FairOver: DRY BRANCH
3.5 MI SW MACON, Macon, IL
Built 1959 Load: 23.3 t ADT: 50
MOUND RD(FAU 7359)
FairOver: STREAM
MOUND & GREENSWITCH, Macon, IL
Built 1966 Load: 24.3 t ADT: 2,775
TR 215(ELWIN RD)
FairOver: STREAM
1.8 MI S LINCOLN TR, Macon, IL
Built 1979 Load: 24.3 t ADT: 50
FAU 7431(OAKLAND A
FairOver: I-72
N EDGE OF DECATUR, Macon, IL
Built 1976 Load: 25.9 t ADT: 3,250
FAP 320(IL 121)
FairOver: WATERWAY
.5 M S PERSHING, Macon, IL
Built 1982 Load: 26.6 t ADT: 15,100
WYCKLES RD(FAS 153
FairOver: SANGAMON RIVER
W. EDGE ROCK SPRINGS, Macon, IL
Built 1964 Load: 28.8 t ADT: 1,900
TR 114B(RILEY RD)
FairOver: WILLOW BRANCH
1.2 MI SE OF MACON, Macon, IL
Built 1977 Load: 28.8 t ADT: 25
TR 203(HERITAGE RD
FairOver: WARD BRANCH
SW OF SOUTHSIDE CC, Macon, IL
Built 1980 Load: 29.2 t ADT: 300
TR 56(GLASGOW RD)
FairOver: STREAM
5.2 MI SW OF MAROA, Macon, IL
Built 1972 Load: 30.1 t ADT: 100
US 36(FAP 320)
FairOver: LAKE DECATUR
IN DECATUR, Macon, IL
Built 1955 Load: 30.5 t ADT: 20,900
FAU 7421
FairOver: FAP 322A(US 51)
1 MI SW OF DECATUR, Macon, IL
Built 1976 Load: 30.8 t ADT: 1,300
FAU 7351
FairOver: I-72
1 MI S HARRISTOWN, Macon, IL
Built 1976 Load: 31.4 t ADT: 250
IL 105(FAP 714)
FairOver: SPRING CREEK
SOUTH SIDE DR DECATU, Macon, IL
Built 1980 Load: 31.4 t ADT: 9,800
FAU 7353(Cantrell
FairOver: FAP 322 (US 51)
.5 MI S HARRISTOWN, Macon, IL
Built 1976 Load: 31.8 t ADT: 1,200
IL 121(FAP 320)
FairOver: CREEK
.5 MI W OF HEMAN, Macon, IL
Built 1931 Load: 32.1 t ADT: 3,750
TR 270(CEMETERY RD
FairOver: I-72
.5 MI SE ARGENTA, Macon, IL
Built 1975 Load: 32.4 t ADT: 100
FAS 551(CH 27)
FairOver: SANGAMON RIVER
.5 MI S LINCOLN PK, Macon, IL
Built 1940 Load: 32.4 t ADT: 250
MOUND RD(FAU 7359)
FairOver: STEVENS CREEK
N SIDE OF DECATUR, Macon, IL
Built 1968 Load: 32.4 t ADT: 4,650
CH 36(BAKER RD)
FairOver: WILLOW BRANCH
2.9 MI SW OF MACON, Macon, IL
Built 1976 Load: 32.4 t ADT: 100
TR 220 D SEE REMAR
FairOver: STREAM
1.5 MI NE DECATUR, Macon, IL
Built 1978 Load: 32.4 t ADT: 525
TR 24(PLEASANT VIE
FairOver: MOSQUITO CREEK
2 MI N BLUE MOUND, Macon, IL
Built 1978 Load: 32.4 t ADT: 200
TR 269(JACKSON RD)
FairOver: WILLOW BRANCH
3.25 MI SW OF MACON, Macon, IL
Built 1978 Load: 32.4 t ADT: 35
TR 53(FAU 7356)
FairOver: STEVENS CREEK
S EDGE HICK PT GOLF, Macon, IL
Built 1978 Load: 32.4 t ADT: 1,750
HILL ST(MS 6670A)
FairOver: SPRING CREEK
0.1 MI N OAKLAND AVE, Macon, IL
Built 1979 Load: 32.4 t ADT: 100
TR 53B(E HICKORY P
FairOver: SPRING CREEK
1.9 MI SE FORSYTHH, Macon, IL
Built 1978 Load: 32.4 t ADT: 1,750
TR 109(ILLIOPOLIS
FairOver: LONG POINT SLOUGH
2 MI W OF NIANTIC, Macon, IL
Built 1981 Load: 32.4 t ADT: 100
TR 109(ILLIOPOLIS
FairOver: WILLOW BRANCH
2.2 MI W NIANTIC, Macon, IL
Built 1981 Load: 32.4 t ADT: 100
CARROLL ST
FairOver: SPRING CREEK
BETWEEN MOUND PERSHI, Macon, IL
Built 1983 Load: 32.4 t ADT: 200
TR 29 Schellabarg
FairOver: STEVENS CREEK
1.6 MI NW FORSYTH, Macon, IL
Built 1979 Load: 32.4 t ADT: 25
TR 128B(OAKLAND AV
FairOver: STEVENS CREEK
1.6 MI NW FORSYTH, Macon, IL
Built 1979 Load: 32.4 t ADT: 100
TR 52(BOODY RD)
FairOver: DRY BRANCH
2.5 MI W MACON, Macon, IL
Built 1981 Load: 32.4 t ADT: 50
TR 157A(RIDGE RD)
FairOver: LONG CREEK
3 MI N OF CASNER, Macon, IL
Built 1980 Load: 32.4 t ADT: 50
TR 255(MOSQUITO CR
FairOver: MOSQUITO CREEK
2 MI NE BLUE MOUND, Macon, IL
Built 1982 Load: 32.4 t ADT: 25
TR 32(ARCHERY CLUB
FairOver: MOSQUITO CREEK
2 MI NE BLUE MOUND, Macon, IL
Built 1982 Load: 32.4 t ADT: 25
TR 4(ACOM ROAD)
FairOver: WILLOW BRANCH
1.7 MI W NIANTIC, Macon, IL
Built 1985 Load: 32.4 t ADT: 100
TR 8(MOONEY RD)
FairOver: WILLOW BRANCH
1 MI NW NIANTIC, Macon, IL
Built 1983 Load: 32.4 t ADT: 50
TR 8(MOONEY RD)
FairOver: WILLOW BRANCH
1 MI NW NIANTIC, Macon, IL
Built 1983 Load: 32.4 t ADT: 50
TR 20A(N 3RD P M
FairOver: WILLOW BRANCH
2.6 MI NE NIANTIC, Macon, IL
Built 1982 Load: 32.4 t ADT: 75
WEAVER AVE(MS 2606
FairOver: STEVENS CREEK
IN CITY OF FORSYTH, Macon, IL
Built 1982 Load: 32.4 t ADT: 2,800
TR 36A(ROSEDALE RD
FairOver: MOSQUITO CREEK
2 MI NE BLUE MOUND, Macon, IL
Built 1982 Load: 32.4 t ADT: 20
TR 270(CEMETERY RD
FairOver: FRIENDS CREEK
1.9 MI NE ARGENTA, Macon, IL
Built 1981 Load: 32.4 t ADT: 150
TR 300(RUCH RD)
FairOver: STREAM
2.3 MI NE OAKLEY, Macon, IL
Built 1982 Load: 32.4 t ADT: 175
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.