US Bridges

West Main ST E over Is 55

Fair

Jefferson County, Missouri · S 416 T 40 N R 6 E · Structure no. 603

Built
1966
59 years old, rebuilt 1987
Condition
Fair
inspected November 2024
Type
Slab
Concrete Continuous
Length
211 ft
4 main spans
Daily traffic
4,446
2024 count
Owner
State
State Highway Agency

About this bridge

West Main ST E over Is 55 is a concrete continuous slab carrying West Main ST E over Is 55 in Jefferson County, Missouri. It was built in 1966 and reconstructed in 1987, so it is 59 years old, older than the Missouri average of 45.1 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 4,446 vehicles a day, roughly 3% of them trucks, projected to reach 7,558 by 2044. The structure is 211 ft (64.3 m) long and 44 ft wide. If it were closed, the detour would be 6.8 mi (11 km).

Location

Open in Google Maps
CarriesWest Main ST E
CrossesIs 55
LocationS 416 T 40 N R 6 E
RouteCity Street 0
CountyJefferson County
StateMissouri
Coordinates38.21951, -90.40645
Functional classUrban Minor Arterial

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionNovember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating51.6 US tons
Inventory rating28.8 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans4
Design loadH 20
Structure length211 ft (64.3 m)
Longest span64 ft (19.5 m)
Deck width44 ft (13.3 m)
Roadway width33 ft (10.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,446 (2024)
Projected traffic7,558 by 2044
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed6.8 mi (11 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNot applicable (no waterway)

Frequently asked questions

When was West Main ST E over Is 55 built?

It was built in 1966, making it 59 years old in 2025. It was reconstructed in 1987.

What condition is West Main ST E over Is 55 in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in November 2024.

How much traffic does West Main ST E over Is 55 carry?

About 4,446 vehicles per day (2024 count), of which roughly 3% are trucks.

How long is West Main ST E over Is 55?

The structure is 211 ft (64.3 m) long with a longest span of 64 ft (19.5 m) and a deck 44 ft wide.

Who owns West Main ST E over Is 55?

It is owned by the State Highway Agency.