Structure 442 · Jefferson County, MO

Is 55 N over Meramec Rvr

Carries Is 55 N over Meramec Rvr, S 403 T 43 N R 6 E.

Overall conditionFair

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

How ratings work
Deck7/9 · Good
Superstructuresets the rating5/9 · Fair
Substructure7/9 · Good
Channelnot part of overall7/9 · Good
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
SEMI-TRUCK · 72 FT1,425 FT OVERALL250 FT0ELEVATION · LENGTHS TO SCALE
Deck 7/9Superstructure 5/9 · sets the ratingSubstructure 7/9

1,425 ft end to end, longest span 185 ft: about 4.0 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 a multi-beam bridge.

Built1964rebuilt 1993
Length1424.9 ft434.3 m
Daily traffic55,375counted 2024
Last inspectedJune 2024every 24 months

Location

StateMissouri
CountyJefferson
LocationS 403 T 43 N R 6 E
CarriesIs 55 N
CrossesMeramec Rvr
Coordinates38.45293, -90.37652

Physical Characteristics

MaterialSteel Continuous
DesignStringer/Multi-beam
Total Length1424.9 ft (434.3 m)
Max Span185.0 ft (56.4 m)
Deck Width76.4 ft (23.3 m)
Deck Area10119.2 sq m
Main Spans5
Year Built1964 (reconstructed 1993)

Traffic

Avg Daily Traffic55,375 (2024)
Truck Traffic18%
Lanes On Bridge5

Inspection & Ownership

Last InspectionJune 2024
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Scour Critical8 — Stable, low risk
Structure Number442

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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