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)

IL 83 SB

Fair

Over: INDIAN CREEK

2.0 M N OF IL 22, Lake, IL

Built 1994 Load: 42.4 t ADT: 27,900

ATKINSON ROAD

Fair

Over: INTERSTATE 94

I94 .8M N ILL 176, Lake, IL

Built 1958 Load: 42.4 t ADT: 1,500

I-94 SB

Fair

Over: WASHINGTON STREET

I94 1.3M S ILL 132, Lake, IL

Built 1958 Load: 42.4 t ADT: 51,150

IL 22

Fair

Over: INDIAN CREEK

0.2 M E OF IL 21, Lake, IL

Built 1982 Load: 42.8 t ADT: 20,600

IL 176

Fair

Over: US 41

LAKE BLUFF, Lake, IL

Built 1980 Load: 43.4 t ADT: 16,900

HAZEL STREET

Fair

Over: W FK N BR CHGO RIV

.4 M E 94 1.9 M S 22, Lake, IL

Built 1968 Load: 44.7 t ADT: 1,450

I-94 SB

Fair

Over: C M S P & P RR

I94 2M S OF ILL 137, Lake, IL

Built 1958 Load: 44.7 t ADT: 67,600

I-94 NB

Fair

Over: CMSP & P RR

I94 2M S OF ILL 137, Lake, IL

Built 1958 Load: 44.7 t ADT: 67,600

IL 120 WB

Fair

Over: GREENLEAF AVE

1.1 M E OF I-94, Lake, IL

Built 1977 Load: 45.4 t ADT: 19,300

IL 120 EB

Fair

Over: GREENLEAF AVE

1.1 M E OF I-94, Lake, IL

Built 1977 Load: 45.4 t ADT: 19,300

HALF DAY RD

Fair

Over: E BR SKOKIE DITCH

0.20 M E OF US 41, Lake, IL

Built 1968 Load: 45.7 t ADT: 9,450

IL 21

Fair

Over: I- 94 TRI STATE TOLL

1.2 M S OF IL 132, Lake, IL

Built 1958 Load: 46.7 t ADT: 13,300

SHERIDAN RD

Fair

Over: 24TH ST

0.5 M N OF IL 137, Lake, IL

Built 1989 Load: 47.3 t ADT: 4,500

WILMOT RD

Fair

Over: W FK N BR CHGO RIVER

.3 M E 94 1.8 M S 22, Lake, IL

Built 1963 Load: 47.6 t ADT: 2,600

IL 137

Fair

Over: I- 94 TRI STATE TOLL

1.0 M W OF IL 43, Lake, IL

Built 1958 Load: 48.3 t ADT: 29,900

DUFFY LANE

Fair

Over: INTERSTATE 94

I94 .8M S ILL 22, Lake, IL

Built 1958 Load: 48.6 t ADT: 1,750

IL 137

Fair

Over: RR - UP & OLD SKOKIE

0.1 M E OF I-94, Lake, IL

Built 1958 Load: 49.6 t ADT: 29,900

US 41

Fair

Over: CREEK

S OF MILL CREEK, Lake, IL

Built 1999 Load: 49.9 t ADT: 24,500

DEERFIELD RD

Fair

Over: I-94(TRI STATE TOLL)

2.4 M E US-45, Lake, IL

Built 1998 Load: 50.5 t ADT: 21,200

BUFFALO GROVE ROAD

Fair

Over: INDIAN CREEK

1.5 M N OF ILL 22, Lake, IL

Built 1966 Load: 50.9 t ADT: 600

IL 137

Fair

Over: US 45

1.4 M S OF IL 120, Lake, IL

Built 1993 Load: 52.2 t ADT: 14,100

IL 60

Fair

Over: I- 94 TRI STATE TOLL

1.9 M W OF US 41, Lake, IL

Built 2007 Load: 52.5 t ADT: 32,800

US 12

Fair

Over: PISTAKEE LAKE CHAN

1/2 M N OF Grand Ave, Lake, IL

Built 1990 Load: 54.1 t ADT: 21,400

IL 120 EB

Fair

Over: RR - CP

0.75 M W OF US 41, Lake, IL

Built 1960 Load: 54.4 t ADT: 28,700

IL 120 WB

Fair

Over: RR - CP

0.75 M W OF US 41, Lake, IL

Built 1960 Load: 54.4 t ADT: 28,700

IL 132 (GRAND AVE)

Fair

Over: I- 94 TRI STATE TOLL

3.0 M N IL 120, Lake, IL

Built 2009 Load: 54.4 t ADT: 33,200

MONTGOMERY RD

Fair

Over: W FK N BR CHGO RIVER

.3 M E 94 1.5 M S 22, Lake, IL

Built 1965 Load: 55.1 t ADT: 20

GREENLEAF TO IL120

Fair

Over: RR - CP

0.75 M W OF US 41, Lake, IL

Built 1977 Load: 55.7 t ADT: 4,200

IL 120 EB TO GRNLE

Fair

Over: RR - CP

0.75 M W OF US 41, Lake, IL

Built 1977 Load: 55.7 t ADT: 4,000

I-94 NB

Fair

Over: US 41 SB (SKOKIE HY)

US 41 SB 1M N IL-173, Lake, IL

Built 1958 Load: 56.4 t ADT: 28,850

US 41

Fair

Over: MILL CREEK

3.5 M N OF GURNEE, Lake, IL

Built 1951 Load: 57.7 t ADT: 24,500

DEERFIELD RD

Fair

Over: BERKELEY AVE

HIGHLAND PARK, Lake, IL

Built 1961 Load: 60.9 t ADT: 21,700

IL 132

Fair

Over: DES PLAINES RIVER

0.2 M E OF IL 21, Lake, IL

Built 1957 Load: 70.6 t ADT: 22,800

MS-1340 MAYFLOWER

Good

Over: RAVINE

MAYFLOWER S OF SPRNG, Lake, IL

Built 1970 Load: 0.0 t ADT: 550

SOUTH DEERE PK DR

Good

Over: SMALL RAVINE

.2 M N LAKE-COOK RD, Lake, IL

Built 1928 Load: 24.3 t ADT: 175

CHECKER RD.

Good

Over: BUFFALO CREEK

0.45M.E.SCHAEFFER RD, Lake, IL

Built 1988 Load: 24.3 t ADT: 900

DEERPATH AVE

Good

Over: SKOKIE RIVER

0.45 MI E OF US 41, Lake, IL

Built 1927 Load: 27.5 t ADT: 15,000

I-94 (TRI STATE)

Good

Over: W.F.N. BR. CHI. RIV

1.3M S OF ILL 22, Lake, IL

Built 1958 Load: 30.8 t ADT: 82,800

WASHINGTON STREET

Good

Over: DESPLAINES RIVER

.2M E OF ILL 21, Lake, IL

Built 1972 Load: 31.1 t ADT: 10,400

BIG HOLLOW ROAD

Good

Over: REDHEAD LAKE CHANNEL

.6 M W OF US-12, Lake, IL

Built 1999 Load: 32.4 t ADT: 13,200

IL 176

Good

Over: EAST SKOKIE DITCH

0.35 M E OF US 41, Lake, IL

Built 2011 Load: 32.4 t ADT: 15,800

MIDLOTHIAN RD

Good

Over: DETENTION PD OUTLET

0.3 MI N PETERSON RD, Lake, IL

Built 2011 Load: 32.4 t ADT: 3,000

DIAMOND LAKE ROAD

Good

Over: INDIAN CREEK

0.75M N OF GILMER RD, Lake, IL

Built 2015 Load: 32.4 t ADT: 2,650

GRASS LAKE ROAD

Good

Over: FOX RIVER

2 M E OF STATE PK RD, Lake, IL

Built 1948 Load: 32.4 t ADT: 6,300

DUFFY LANE

Good

Over: W FK N BR CHICAGO RV

1.3 MI E CH 58, Lake, IL

Built 1958 Load: 32.4 t ADT: 1,350

WADSWORTH RD.

Good

Over: DESPLAINES RIVER

0.25M.E.OF US-41, Lake, IL

Built 1987 Load: 32.4 t ADT: 14,600

OAK KNOLLS RD.

Good

Over: FLINT CREEK

0.5M.N.LAKE COOK RD., Lake, IL

Built 1988 Load: 32.4 t

IL 120

Good

Over: DRAIN DITCH

.2 EAST OF GILMER RD, Lake, IL

Built 1993 Load: 32.4 t ADT: 26,300

KELSEY RD

Good

Over: FLINT CR

1 MI N OF IL 22, Lake, IL

Built 2006 Load: 32.4 t ADT: 11,100

HUNT CLUB RD

Good

Over: MILL CREEK

2M N OF IL132, Lake, IL

Built 2006 Load: 32.4 t ADT: 10,250
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.