US Bridges

Mn 23 over Little Willow River

Fair

Pine County, Minnesota · 3.0 MI NE of Bruno · Structure no. 6074

Built
1936
89 years old
Condition
Fair
inspected May 2023
Type
Culvert
Concrete
Length
22 ft
2 main spans
Daily traffic
757
2022 count
Owner
State
State Highway Agency

About this bridge

Mn 23 over Little Willow River is a concrete culvert carrying Mn 23 over Little Willow River in Pine County, Minnesota. It was built in 1936, so it is 89 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 757 vehicles a day, roughly 6% of them trucks, projected to reach 600 by 2042. The structure is 22 ft (6.8 m) long. If it were closed, the detour would be 8.1 mi (13 km).

CarriesMn 23
CrossesLittle Willow River
Location3.0 MI NE of Bruno
RouteState Highway 23
Coordinates46.30955, -92.62185
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
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating43.2 US tons
Inventory rating32.4 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans2
Design loadH 15
Structure length22 ft (6.8 m)
Longest span10 ft (3 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic757 (2022)
Projected traffic600 by 2042
Trucks6%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed8.1 mi (13 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$49 million
NavigationNo navigation control on waterway

Frequently asked questions

When was Mn 23 over Little Willow River built?

It was built in 1936, making it 89 years old in 2025.

What condition is Mn 23 over Little Willow 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 23 over Little Willow River carry?

About 757 vehicles per day (2022 count), of which roughly 6% are trucks.

How long is Mn 23 over Little Willow River?

The structure is 22 ft (6.8 m) long with a longest span of 10 ft (3 m).

Who owns Mn 23 over Little Willow River?

It is owned by the State Highway Agency.