US Bridges

18th ST over Metrolink

Fair

St. Louis city, Missouri · S 363 T 45 N R 7 E · Structure no. 32030

Built
1991
34 years old
Condition
Fair
inspected April 2023
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
55 ft
1 main span
Daily traffic
14,500
2023 count
Owner
Local
Other Local Agency

About this bridge

18th ST over Metrolink is a prestressed concrete box beam or girders - multiple carrying 18th ST over Metrolink in St. Louis city, Missouri. It was built in 1991, so it is 34 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 14,500 vehicles a day, roughly 5% of them trucks, projected to reach 19,575 by 2043. The structure is 55 ft (16.7 m) long and 80 ft wide.

Location

Open in Google Maps
Carries18th ST
CrossesMetrolink
LocationS 363 T 45 N R 7 E
RouteCity Street 0
CountySt. Louis city
StateMissouri
Coordinates38.62675, -90.20715
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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry2: Basically intolerable, requiring high priority of replacement
Approach roadway alignment8: Equal to present desirable criteria
Operating rating68.5 US tons
Inventory rating40.7 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length55 ft (16.7 m)
Longest span51 ft (15.5 m)
Deck width80 ft (24.4 m)
Roadway width48 ft (14.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic14,500 (2023)
Projected traffic19,575 by 2043
Trucks5%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesRailroad
Detour if closed—
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerOther Local Agency
Maintained byOther Local Agency
Historic statusHistorical significance not determinable at this time
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$806,000 (2025 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was 18th ST over Metrolink built?

It was built in 1991, making it 34 years old in 2025.

What condition is 18th ST over Metrolink 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 April 2023.

How much traffic does 18th ST over Metrolink carry?

About 14,500 vehicles per day (2023 count), of which roughly 5% are trucks.

How long is 18th ST over Metrolink?

The structure is 55 ft (16.7 m) long with a longest span of 51 ft (15.5 m) and a deck 80 ft wide.

Who owns 18th ST over Metrolink?

It is owned by the Other Local Agency.