Structure 82000400000000 · St. Clair County, IL

Psb I-55 64;us 40 over Mississippi River

Carries Psb I-55 64;us 40 over Mississippi River, Poplar ST Br - Modot.

Overall conditionFair

Set by its lowest-rated component: Deck and Superstructure and Substructure at 5 of 9.

How ratings work
Decksets the rating5/9 · Fair
Superstructuresets the rating5/9 · Fair
Substructuresets the rating5/9 · Fair
Channelnot part of overall6/9 · Satisfactory
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
SEMI-TRUCK · 72 FT2,165 FT OVERALL250 FT0ELEVATION · LENGTHS TO SCALE
Deck 5/9Superstructure 5/9Substructure 5/9

2,165 ft end to end, longest span 600 ft: about 6.0 football fields. 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 an orthotropic-deck bridge.

Built196363 years old
Length2165.0 ft659.9 m
Daily traffic113,200counted 2024
Last inspectedOctober 2024every 24 months

Location

StateIllinois
CountySt. Clair
LocationPoplar ST Br - Modot
CarriesPsb I-55 64;us 40
CrossesMississippi River
Coordinates38.61792, -90.18251

Physical Characteristics

MaterialSteel Continuous
DesignOrthotropic
Total Length2165.0 ft (659.9 m)
Max Span600.1 ft (182.9 m)
Deck Width112.9 ft (34.4 m)
Deck Area22700.6 sq m
Main Spans5
Year Built1963

Traffic

Avg Daily Traffic113,200 (2024)
Truck Traffic13%
Lanes On Bridge8

Inspection & Ownership

Last InspectionOctober 2024
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Scour Critical8 — Stable, low risk
Structure Number082000400000000

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.

Nearby Bridges