County profile · official public datasets

Lake County, IL

251 public highway bridges tracked in the FHWA National Bridge Inventory: 37.1% rated Good, 53% Fair, 10% Poor.

251
Public bridges
37.1%
Good condition
10%
Poor condition

The verdict

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

Lake County posts a higher-than-median Poor-condition share among rated counties in the state across mid-size county bridge inventory.

71st
of 102 on Poor share
10%
Poor-condition share
251
public highway bridges
1976
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.

Lake County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Lake County ranks #71 of 102 Illinois counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 10%). Lake County, Illinois contains 251 public highway bridges. Roughly 37.1% are rated “Good,” 53% “Fair,” and 10% “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

251

Public highway bridges in Lake County

Good condition

37.1%

93 of 251 rated 7-9

Fair condition

53%

133 of 251 rated 5-6

Poor condition

10%

25 of 251 rated 4 or below

In-state Poor-share rank

#71 of 102

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

Condition distribution

Share of 251 NBI-tracked bridges by lowest applicable component rating.

Good
37.1% (93)
Fair
53% (133)
Poor
10% (25)

Lake County's Poor-condition bridges carry 142,235 vehicle crossings a day

That is 4.1% of the county's reported daily bridge traffic on 10% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 5,689 crossings a day against 12,971 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 250 of 251 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

47% of Lake County's bridges have passed the 50-year mark

118 of the 251 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 37.1% 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 21.6% of the county's Poor-condition bridge traffic

IL 120 EB over DES PLAINES RIVER, built 1959, carries 30,700 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 25-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 142,235 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

When Lake County's bridges were built

251 bridges with a recorded construction year, grouped by decade

bridges

What this shows Construction peaked in the 1950s, when 44 of the county's bridges still in the inventory were built, which is 17.5% of those with a recorded year. That cohort is now 65 to 74 years old in the 2024 inventory. Its average build year (1976) matches the Illinois average (1979).

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

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

The 5 Illinois counties nearest Lake County in number of bridges, with their condition splits. Its 10% Poor share is the 4th-lowest of these 6. Its average build year of 1976 against a peer-group mean of 1977 is in line with the group.

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

Bridge inventory size and condition shares for Lake County and the 5 Illinois counties closest to it in inventory size
County Bridges Poor
DeKalb County 261 13%
Jefferson County 260 6.2%
Effingham County 253 4.7%
Lake County (this page) 251 10%
Piatt County 246 6.1%
Macoupin County 242 17.8%

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

Similar inventory size

Nearest county inventories outside IL (251 bridges here).

Similar average build year

Nearest mean year-built outside IL (1976 here).

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

All bridges (251)

COFFIN ROAD

Fair

Over: BUFFALO CREEK

.5 M N 53 1.0 M W 83, Lake, IL

Built 1925 Load: 6.2 t ADT: 2,500

LEONARD DR

Fair

Over: SPINNEY RUN CR

700 FT N ILL RT 120, Lake, IL

Built 1977 Load: 12.3 t ADT: 800

IL 176

Fair

Over: BANGS LAKE OUTLET

.8 M E OF IL 59 US12, Lake, IL

Built 1931 Load: 13.6 t ADT: 16,200

MS-1340 MAYFLOWER

Fair

Over: RAVINE

MAYFLOWER N OF ILL R, Lake, IL

Built 1968 Load: 15.2 t ADT: 475

MS-4101 Dean Avenu

Fair

Over: RAVINE

1.5 N CO LINE, Lake, IL

Built 1928 Load: 16.8 t ADT: 900

MS-1117 ST JOHNS A

Fair

Over: RAVINE

3.3 M N LAKE COOK RD, Lake, IL

Built 1972 Load: 18.1 t ADT: 1,400

ROGER WILLIAMS

Fair

Over: RAVINE

0.2M E LK MICHIGAN, Lake, IL

Built 1915 Load: 19.4 t ADT: 3,750

IL 173

Fair

Over: SEQUOIT CREEK

0.5 M W OF IL 59, Lake, IL

Built 1931 Load: 21.4 t ADT: 13,900

Oak Knoll Road

Fair

Over: Flint Creek

.1M E of Ridge Rd., Lake, IL

Built 1926 Load: 24.3 t ADT: 225

PORT CLINTON RD.

Fair

Over: S.BR.INDIAN CREEK

1.5M W OF US 45, Lake, IL

Built 1956 Load: 24.3 t ADT: 1,150

LAKE ROAD

Fair

Over: RAVINE

LAKE RD S OF SPRUCE, Lake, IL

Built 1979 Load: 24.6 t ADT: 525

LAKE COOK ROAD

Fair

Over: W F N BR CHICAGO RIV

0.1 EAST OF PINE ST, Lake, IL

Built 1989 Load: 27.5 t ADT: 29,800

US 12

Fair

Over: NIPPERSINK LAKE CHAN

1 M NW OF IL 132, Lake, IL

Built 1990 Load: 28.5 t ADT: 21,400

LAKEVIEW AVE

Fair

Over: INLET FROM DIAMOND L

S EDGE OF DIAMOND LK, Lake, IL

Built 1969 Load: 28.5 t ADT: 175

I-94 SB

Fair

Over: MILL CREEK

I-94 205 M N ILL-132, Lake, IL

Built 1958 Load: 31.8 t ADT: 39,100

I-94 NB

Fair

Over: MILL CREEK

I-94 2.5M N ILL 132, Lake, IL

Built 1958 Load: 31.8 t ADT: 39,100

IL 131 (GREEN BAY)

Fair

Over: RR - EJ&E

1.1 M S OF IL 137, Lake, IL

Built 1954 Load: 32.1 t ADT: 10,300

10TH STREET

Fair

Over: PETTIBONE CREEK

0.01KM S OF CROSLEY DR, Lake, IL

Built 1938 Load: 32.4 t ADT: 210

US 41

Fair

Over: DEERPATH RD

LAKE FOREST, Lake, IL

Built 1937 Load: 32.4 t ADT: 41,000

IL 120 WB

Fair

Over: STREAM

0.1 M W OF IL 21, Lake, IL

Built 1960 Load: 32.4 t ADT: 27,900

IL 120 EB

Fair

Over: STREAM

0.1 M W OF IL 21, Lake, IL

Built 1960 Load: 32.4 t ADT: 27,900

IL 120

Fair

Over: RR - UP & OLD SKOKIE

GURNEE, Lake, IL

Built 1959 Load: 32.4 t ADT: 28,400

DEERFIELD ROAD

Fair

Over: M F N BR CHICAGO RIV

0.9 MI W OF IL 41, Lake, IL

Built 1962 Load: 32.4 t ADT: 3,100

DEERFIELD ROAD

Fair

Over: DESPLAINES RIVER

0.4 MI E OF US-45, Lake, IL

Built 1993 Load: 32.4 t ADT: 15,400

IL 132

Fair

Over: MILL CREEK

0.3 M E OF US45, Lake, IL

Built 1969 Load: 32.4 t ADT: 14,500

IL 137

Fair

Over: SKOKIE RIVER

0.18 M E US 41, Lake, IL

Built 1942 Load: 32.4 t ADT: 19,200

MATHON DR

Fair

Over: UP RR

0.3 M E SHERIDAN, Lake, IL

Built 1968 Load: 32.4 t ADT: 3,650

PULASKI DR 14TH ST

Fair

Over: US RTE 41

.6 MI E ILL 43, Lake, IL

Built 1979 Load: 32.4 t ADT: 14,200

ARLNTON HTS RD SB

Fair

Over: BUFFALO CREEK

0.4 MI N OF COOK CO, Lake, IL

Built 1980 Load: 32.4 t ADT: 12,350

GRASS LAKE RD.

Fair

Over: W-WAY INLET BLUFF LK

0.7M.W.OF IL-59, Lake, IL

Built 1990 Load: 32.4 t ADT: 9,300

RUSSELL RD

Fair

Over: DES PLAINES RIV

.70 W OF KILBOURN, Lake, IL

Built 1991 Load: 32.4 t ADT: 4,850

STATE LINE RD

Fair

Over: DUTCH GAP CANAL

1.0 MI W US 45, Lake, IL

Built 1960 Load: 32.4 t ADT: 4,850

ROLLINS ROAD

Fair

Over: Manitou Creek

.5M W OF WILSON RD, Lake, IL

Built 2001 Load: 32.4 t ADT: 8,850

KILBOURNE RD

Fair

Over: DES PLAINES TRIB

0.05M S.OFSTATE LINE, Lake, IL

Built 1996 Load: 32.4 t ADT: 3,500

GREGGS PARKWAY

Fair

Over: SEAVEY DRAINAGE DTCH

1 MI W. OF ILL 21, Lake, IL

Built 2004 Load: 32.4 t ADT: 9,900

JUNIPER CT

Fair

Over: W FRK N BR CHGO RIV

.7 M E 94 2.1 M S 22, Lake, IL

Built 1965 Load: 32.4 t ADT: 125

CARRIAGE WAY

Fair

Over: MD FRK N BR CHGO RIV

.8 M E 43 2.5 M S 22, Lake, IL

Built 1977 Load: 32.4 t ADT: 125

DEERFIELD ROAD

Fair

Over: NB CHICAGO RIVER

0.6 MI W OF IL 43, Lake, IL

Built 1994 Load: 32.4 t ADT: 16,600

CUNNINGHAM COURT

Fair

Over: SHERMAN COMER CREEK

990 E HUNT CLUB DR, Lake, IL

Built 2007 Load: 32.4 t ADT: 200

ATWATER PARKWAY

Fair

Over: BOAT CHANNEL

.2 M N IL-132, Lake, IL

Built 1997 Load: 32.4 t ADT: 75

LEONARD DRIVE

Fair

Over: SHERMAN COMERS CREEK

1800S OF GAGE LK RD, Lake, IL

Built 1992 Load: 32.4 t ADT: 850

LINDEN AVE

Fair

Over: RAVINE

1.9 M N LAKE COOK RD, Lake, IL

Built 1976 Load: 32.4 t ADT: 350

WAVERLY RD

Fair

Over: RAVINE

1.9 N LAKE COOK RD., Lake, IL

Built 1968 Load: 32.4 t ADT: 75

FREDRICKSON PLACE

Fair

Over: SKOKIE DITCH

.2 M E 41, Lake, IL

Built 1985 Load: 32.4 t ADT: 900

WOODLAND DRIVE

Fair

Over: FLINT CREEK

1 M N23 2 M W59, Lake, IL

Built 2015 Load: 32.4 t ADT: 325

WALDEN LANE

Fair

Over: RAVINE

WALDEN AT WESTLEIH, Lake, IL

Built 1914 Load: 32.4 t ADT: 175

ONWENTSIA ROAD

Fair

Over: SKOKIE RIVER

ONWENTSIA W GREEN BA, Lake, IL

Built 1993 Load: 32.4 t ADT: 525

LAKE SHR.DR.

Fair

Over: ROUND LAKE OUTFALL

1.2M.W.OF IL-83, Lake, IL

Built 1990 Load: 32.4 t ADT: 850

MAC GILLIS DR

Fair

Over: SQUAW CREEK

0.1 MI S IL 134, Lake, IL

Built 2016 Load: 32.4 t ADT: 1,250

PATTEN ROAD

Fair

Over: PAVED ROAD

0.5 KM N OF FINLEY ROAD, Lake, IL

Built 2005 Load: 32.6 t ADT: 1,050
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.