US Bridges

Is 64 W over Mo 340

Fair

St. Louis County, Missouri · S 415 T 45 N R 4 E · Structure no. 1373

Built
1968
57 years old, rebuilt 1989
Condition
Fair
inspected October 2024
Type
Slab
Concrete Continuous
Length
245 ft
4 main spans
Daily traffic
66,484
2024 count
Owner
State
State Highway Agency

About this bridge

Is 64 W over Mo 340 is a concrete continuous slab carrying Is 64 W over Mo 340 in St. Louis County, Missouri. It was built in 1968 and reconstructed in 1989, so it is 57 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 5 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 66,484 vehicles a day, roughly 8% of them trucks, projected to reach 83,105 by 2044. The structure is 245 ft (74.7 m) long and 52 ft wide. If it were closed, the detour would be 0.6 mi (1 km).

Location

Open in Google Maps
CarriesIs 64 W
CrossesMo 340
LocationS 415 T 45 N R 4 E
RouteInterstate 64
CountySt. Louis County
StateMissouri
Coordinates38.65305, -90.55833
Functional classUrban Principal Arterial - Interstate

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure7 GoodSome minor problems.
Last inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment7: Better than present minimum criteria
Operating rating71.4 US tons
Inventory rating42.7 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length245 ft (74.7 m)
Longest span70 ft (21.3 m)
Deck width52 ft (16 m)
Roadway width50 ft (15.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic66,484 (2024)
Projected traffic83,105 by 2044
Trucks8%
Lanes on structure3
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed0.6 mi (1 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

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 Is 64 W over Mo 340 built?

It was built in 1968, making it 57 years old in 2025. It was reconstructed in 1989.

What condition is Is 64 W over Mo 340 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 October 2024.

How much traffic does Is 64 W over Mo 340 carry?

About 66,484 vehicles per day (2024 count), of which roughly 8% are trucks.

How long is Is 64 W over Mo 340?

The structure is 245 ft (74.7 m) long with a longest span of 70 ft (21.3 m) and a deck 52 ft wide.

Who owns Is 64 W over Mo 340?

It is owned by the State Highway Agency.