US Bridges

US 61 S over Is 64

Fair

St. Charles County, Missouri · S 30 T 47 N R 2 E · Structure no. 1718

Built
1971
54 years old
Condition
Fair
inspected September 2023
Type
Slab
Concrete Continuous
Length
137 ft
3 main spans
Daily traffic
26,120
2024 count
Owner
State
State Highway Agency

About this bridge

US 61 S over Is 64 is a concrete continuous slab carrying US 61 S over Is 64 in St. Charles County, Missouri. It was built in 1971, so it is 54 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 26,120 vehicles a day, roughly 5% of them trucks, projected to reach 44,404 by 2044. The structure is 137 ft (41.8 m) long and 49 ft wide. If it were closed, the detour would be 14.3 mi (23 km).

Location

Open in Google Maps
CarriesUS 61 S
CrossesIs 64
LocationS 30 T 47 N R 2 E
RouteU.S. Route 61
CountySt. Charles County
StateMissouri
Coordinates38.8084, -90.84024
Functional classUrban Principal Arterial - Other Freeway or Expressway

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.
Substructure7 GoodSome minor problems.
Last inspectionSeptember 2023
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 rating66.5 US tons
Inventory rating39.7 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length137 ft (41.8 m)
Longest span52 ft (15.8 m)
Deck width49 ft (14.9 m)
Roadway width46 ft (14 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic26,120 (2024)
Projected traffic44,404 by 2044
Trucks5%
Lanes on structure3
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway
Detour if closed14.3 mi (23 km)
TollOn a free road
National Highway SystemYes

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 US 61 S over Is 64 built?

It was built in 1971, making it 54 years old in 2025.

What condition is US 61 S over Is 64 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 September 2023.

How much traffic does US 61 S over Is 64 carry?

About 26,120 vehicles per day (2024 count), of which roughly 5% are trucks.

How long is US 61 S over Is 64?

The structure is 137 ft (41.8 m) long with a longest span of 52 ft (15.8 m) and a deck 49 ft wide.

Who owns US 61 S over Is 64?

It is owned by the State Highway Agency.