Structure 49019800000000 · Lake County, IL

Il 173 over Boat Channel

Carries Il 173 over Boat Channel, 1.75 M W Of Il 59.

Overall conditionGood

Set by its lowest-rated component: Deck and Superstructure and Substructure at 8 of 9.

How ratings work
Decksets the rating8/9 · Very Good
Superstructuresets the rating8/9 · Very Good
Substructuresets the rating8/9 · Very Good
Channelnot part of overall7/9 · Good
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
SEMI-TRUCK · 72 FT143 FT OVERALL25 FT0ELEVATION · LENGTHS TO SCALE
Deck 8/9Superstructure 8/9Substructure 8/9

143 ft end to end, longest span 72 ft. Lengths and the semi-truck on the deck are drawn to the same scale. Each part is colored by its latest inspection rating. The inventory records lengths but not heights or the layout of the shorter spans, so those are drawn as typical for a multi-beam bridge.

Built201115 years old
Length142.7 ft43.5 m
Daily traffic11,200counted 2023
Last inspectedSeptember 2021every 48 months

Location

StateIllinois
CountyLake
Location1.75 M W Of Il 59
CarriesIl 173
CrossesBoat Channel
Coordinates42.47887, -88.13679

Physical Characteristics

MaterialSteel Continuous
DesignStringer/Multi-beam
Total Length142.7 ft (43.5 m)
Max Span71.5 ft (21.8 m)
Deck Width46.6 ft (14.2 m)
Deck Area617.7 sq m
Main Spans2
Year Built2011

Traffic

Avg Daily Traffic11,200 (2023)
Truck Traffic10%
Lanes On Bridge2

Inspection & Ownership

Last InspectionSeptember 2021
Inspection FrequencyEvery 48 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Scour Critical8 — Stable, low risk
Structure Number049019800000000

How Bridge Ratings Work

Inspectors rate each major part of a bridge (the deck you drive on, the superstructure of beams that holds it up, and the substructure of piers and abutments beneath) on a 0–9 scale. A bridge's overall condition is its lowest of those ratings, so one deteriorated component makes the whole bridge "poor."

0Failed
1Imminent failure
2Critical
3Serious
4Poor
5Fair
6Satisfactory
7Good
8Very good
9Excellent
Good · lowest component 7–9
Fair · lowest component 5–6
Poor · lowest component 0–4

A poor rating is not a closure. It means the bridge is flagged for priority repair or replacement; bridges judged unsafe are closed or posted with weight limits. The waterway (channel) rating is reported, but it does not count toward the overall classification.

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