Structure 24504503600005 · St. Charles County, LA

I0310 over Swamp

Carries I0310 over Swamp, 0.01 M South Of I-10.

Overall conditionGood

Set by its lowest-rated component: Deck and Substructure at 7 of 9.

How ratings work
Decksets the rating7/9 · Good
Superstructure8/9 · Very Good
Substructuresets the rating7/9 · Good
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
SEMI-TRUCK · 72 FT2,206 FT OVERALL250 FT0ELEVATION · LENGTHS TO SCALE
Deck 7/9 · sets the ratingSuperstructure 8/9Substructure 7/9 · sets the rating

2,206 ft end to end, longest span 74 ft: about 6.1 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 slab bridge.

Built199234 years old
Length2206.0 ft672.4 m
Daily traffic—reported figure implausible
Last inspectedSeptember 2023every 24 months

Location

StateLouisiana
CountySt. Charles
Location0.01 M South Of I-10
CarriesI0310
CrossesSwamp
Coordinates30.00741, -90.29759

Physical Characteristics

MaterialConcrete Continuous
DesignSlab
Total Length2206.0 ft (672.4 m)
Max Span74.1 ft (22.6 m)
Deck Width34.8 ft (10.6 m)
Deck Area7127.4 sq m
Main Spans30
Year Built1992

Traffic

Avg Daily Traffic56,783 (2021)
That is about 56,783 vehicles per lane per day — beyond what any U.S. road carries (the busiest freeways run about 25,000–30,000). It is almost certainly a data-entry error in the National Bridge Inventory, so we leave this bridge out of traffic rankings.
Truck Traffic25%
Lanes On Bridge1

Inspection & Ownership

Last InspectionSeptember 2023
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Scour Critical8 — Stable, low risk
Structure Number024504503600005

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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