US Bridges

Mn 73 over West Swan River

Fair

St. Louis County, Minnesota · 9.2 MI S of S JCT TH 169 · Structure no. 9261

Built
1957
68 years old
Condition
Fair
inspected May 2023
Type
Channel Beam
Concrete
Length
75 ft
3 main spans
Daily traffic
1,300
2019 count
Owner
State
State Highway Agency

About this bridge

Mn 73 over West Swan River is a concrete channel beam carrying Mn 73 over West Swan River in St. Louis County, Minnesota. It was built in 1957, so it is 68 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 1,300 vehicles a day, roughly 3% of them trucks, projected to reach 1,300 by 2039. The structure is 75 ft (22.9 m) long and 35 ft wide. If it were closed, the detour would be 26.1 mi (42 km).

Location

Open in Google Maps
CarriesMn 73
CrossesWest Swan River
Location9.2 MI S of S JCT TH 169
RouteState Highway 73
CountySt. Louis County
StateMinnesota
Coordinates47.27695, -93.02412
Functional classRural 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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 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 geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating61.2 US tons
Inventory rating40.3 US tons

Structure

Structure typeChannel Beam
MaterialConcrete
DeckConcrete, precast panels
Main spans3
Design loadHS 20 + Mod
Structure length75 ft (22.9 m)
Longest span25 ft (7.6 m)
Deck width35 ft (10.7 m)
Roadway width33 ft (10.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,300 (2019)
Projected traffic1,300 by 2039
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed26.1 mi (42 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$261 million
NavigationNo navigation control on waterway

Frequently asked questions

When was Mn 73 over West Swan River built?

It was built in 1957, making it 68 years old in 2025.

What condition is Mn 73 over West Swan 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 May 2023.

How much traffic does Mn 73 over West Swan River carry?

About 1,300 vehicles per day (2019 count), of which roughly 3% are trucks.

How long is Mn 73 over West Swan River?

The structure is 75 ft (22.9 m) long with a longest span of 25 ft (7.6 m) and a deck 35 ft wide.

Who owns Mn 73 over West Swan River?

It is owned by the State Highway Agency.