US Bridges

I 35 over ST Louis River

Fair

Carlton County, Minnesota · 0.3 MI N of JCT TH 45 · Structure no. 09808

Built
1971
54 years old
Condition
Fair
inspected July 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
486 ft
4 main spans
Daily traffic
14,250
2016 count
Owner
State
State Highway Agency

About this bridge

I 35 over ST Louis River is a steel continuous stringer/multi-beam or girder carrying I 35 over ST Louis River in Carlton County, Minnesota. It was built in 1971, so it is 54 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 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 14,250 vehicles a day, roughly 10% of them trucks, projected to reach 14,250 by 2036. The structure is 486 ft (148 m) long and 44 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesI 35
CrossesST Louis River
Location0.3 MI N of JCT TH 45
RouteInterstate 35
CountyCarlton County
StateMinnesota
Coordinates46.69951, -92.42003
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
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating63.4 US tons
Inventory rating38 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length486 ft (148 m)
Longest span137 ft (41.8 m)
Deck width44 ft (13.5 m)
Roadway width40 ft (12.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic14,250 (2016)
Projected traffic14,250 by 2036
Trucks10%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 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—
NavigationNo navigation control on waterway

Frequently asked questions

When was I 35 over ST Louis River built?

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

What condition is I 35 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 July 2024.

How much traffic does I 35 over ST Louis River carry?

About 14,250 vehicles per day (2016 count), of which roughly 10% are trucks.

How long is I 35 over ST Louis River?

The structure is 486 ft (148 m) long with a longest span of 137 ft (41.8 m) and a deck 44 ft wide.

Who owns I 35 over ST Louis River?

It is owned by the State Highway Agency.