US Bridges

Csah 8 over ST Louis River

Fair

St. Louis County, Minnesota · 0.5 MI E of JCT TH 73 · Structure no. 69505

Built
1974
51 years old
Condition
Fair
inspected September 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
303 ft
3 main spans
Daily traffic
590
2019 count
Owner
County
County Highway Agency

About this bridge

Csah 8 over ST Louis River is a prestressed concrete stringer/multi-beam or girder carrying Csah 8 over ST Louis River in St. Louis County, Minnesota. It was built in 1974, so it is 51 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 590 vehicles a day, projected to reach 550 by 2039. The structure is 303 ft (92.4 m) long and 36 ft wide. If it were closed, the detour would be 21.7 mi (35 km).

Location

Open in Google Maps
CarriesCsah 8
CrossesST Louis River
Location0.5 MI E of JCT TH 73
RouteCounty Highway 8
CountySt. Louis County
StateMinnesota
Coordinates46.92896, -92.90443
Functional classRural Minor Collector

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.
Substructure7 GoodSome minor problems.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating51 US tons
Inventory rating30.6 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length303 ft (92.4 m)
Longest span100 ft (30.5 m)
Deck width36 ft (10.9 m)
Roadway width32 ft (9.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic590 (2019)
Projected traffic550 by 2039
Trucks—
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed21.7 mi (35 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty 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 Csah 8 over ST Louis River built?

It was built in 1974, making it 51 years old in 2025.

What condition is Csah 8 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 2024.

How much traffic does Csah 8 over ST Louis River carry?

About 590 vehicles per day (2019 count).

How long is Csah 8 over ST Louis River?

The structure is 303 ft (92.4 m) long with a longest span of 100 ft (30.5 m) and a deck 36 ft wide.

Who owns Csah 8 over ST Louis River?

It is owned by the County Highway Agency.