US Bridges

Mn 23 over ST Louis River

Fair

St. Louis County, Minnesota · At Wis State Line · Structure no. 6313

Built
1919
106 years old, rebuilt 2016
Condition
Fair
inspected September 2023
Type
Arch - Deck
Concrete Continuous
Length
680 ft
6 main spans
Daily traffic
1,650
2019 count
Owner
State
State Highway Agency

About this bridge

Mn 23 over ST Louis River is a concrete continuous arch - deck carrying Mn 23 over ST Louis River in St. Louis County, Minnesota. It was built in 1919 and reconstructed in 2016, so it is 106 years old, older than the Minnesota average of 38.5 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 1,650 vehicles a day, roughly 9% of them trucks, projected to reach 1,550 by 2039. The structure is 680 ft (207.4 m) long and 48 ft wide. If it were closed, the detour would be 14.9 mi (24 km).

Location

Open in Google Maps
CarriesMn 23
CrossesST Louis River
LocationAt Wis State Line
RouteState Highway 23
CountySt. Louis County
StateMinnesota
Coordinates46.65896, -92.28354
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.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourCountermeasures installed to correct a previously existing problem
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating51.8 US tons
Inventory rating32.4 US tons

Structure

Structure typeArch - Deck
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans6
Design loadHS 15
Structure length680 ft (207.4 m)
Longest span126 ft (38.5 m)
Deck width48 ft (14.7 m)
Roadway width36 ft (11 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,650 (2019)
Projected traffic1,550 by 2039
Trucks9%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed14.9 mi (24 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$1,000 million
NavigationNo navigation control on waterway

Frequently asked questions

When was Mn 23 over ST Louis River built?

It was built in 1919, making it 106 years old in 2025. It was reconstructed in 2016.

What condition is Mn 23 over ST Louis River 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 Mn 23 over ST Louis River carry?

About 1,650 vehicles per day (2019 count), of which roughly 9% are trucks.

How long is Mn 23 over ST Louis River?

The structure is 680 ft (207.4 m) long with a longest span of 126 ft (38.5 m) and a deck 48 ft wide.

Who owns Mn 23 over ST Louis River?

It is owned by the State Highway Agency.