US Bridges

Mo 370 E over Missouri Rvr Cst Main S

Fair

St. Charles County, Missouri · S 32 T 47 N R 5 E · Structure no. 3729

Built
1992
33 years old
Condition
Fair
inspected June 2023
Type
Truss - Thru
Steel
Length
3,455 ft
1 main span
Daily traffic
23,892
2024 count
Owner
State
State Highway Agency

About this bridge

Mo 370 E over Missouri Rvr Cst Main S is a steel truss - thru carrying Mo 370 E over Missouri Rvr Cst Main S in St. Charles County, Missouri. It was built in 1992, so it is 33 years old, younger 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 23,892 vehicles a day, roughly 5% of them trucks, projected to reach 40,616 by 2044. The structure is 3,455 ft (1,053.1 m) long and 57 ft wide. If it were closed, the detour would be 0.6 mi (1 km).

Location

Open in Google Maps
CarriesMo 370 E
CrossesMissouri Rvr Cst Main S
LocationS 32 T 47 N R 5 E
RouteState Highway 370
CountySt. Charles County
StateMissouri
Coordinates38.79811, -90.46681
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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionJune 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating52.6 US tons
Inventory rating31.7 US tons

Structure

Structure typeTruss - Thru
MaterialSteel
DeckConcrete, cast-in-place
Main spans1 (+22 approach)
Design loadHS 20 + Mod
Structure length3,455 ft (1,053.1 m)
Longest span625 ft (190.5 m)
Deck width57 ft (17.5 m)
Roadway width55 ft (16.7 m)
Vertical clearance over deck17 ft (5 m)

Traffic and service

Average daily traffic23,892 (2024)
Projected traffic40,616 by 2044
Trucks5%
Lanes on structure3
Traffic directionOne-way traffic
CarriesHighway
CrossesHighway and waterway
Detour if closed0.6 mi (1 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—
NavigationNavigation control on waterway (bridge permit required)

Frequently asked questions

When was Mo 370 E over Missouri Rvr Cst Main S built?

It was built in 1992, making it 33 years old in 2025.

What condition is Mo 370 E over Missouri Rvr Cst Main S 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 June 2023.

How much traffic does Mo 370 E over Missouri Rvr Cst Main S carry?

About 23,892 vehicles per day (2024 count), of which roughly 5% are trucks.

How long is Mo 370 E over Missouri Rvr Cst Main S?

The structure is 3,455 ft (1,053.1 m) long with a longest span of 625 ft (190.5 m) and a deck 57 ft wide.

Who owns Mo 370 E over Missouri Rvr Cst Main S?

It is owned by the State Highway Agency.