US Bridges

Mn 56 over N Br Upper Iowa River

Fair

Mower County, Minnesota · 3.0 MI W of JCT Csah 8 · Structure no. 95766

Built
1983
42 years old
Condition
Fair
inspected August 2023
Type
Culvert
Concrete
Length
70 ft
3 main spans
Daily traffic
1,357
2022 count
Owner
State
State Highway Agency

About this bridge

Mn 56 over N Br Upper Iowa River is a concrete culvert carrying Mn 56 over N Br Upper Iowa River in Mower County, Minnesota. It was built in 1983, so it is 42 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 1,357 vehicles a day, roughly 21% of them trucks, projected to reach 1,100 by 2042. The structure is 70 ft (21.2 m) long. If it were closed, the detour would be 19.9 mi (32 km).

CarriesMn 56
CrossesN Br Upper Iowa River
Location3.0 MI W of JCT Csah 8
RouteState Highway 56
Coordinates43.558, -92.61863
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 protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable 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 spans3
Design loadHS 20
Structure length70 ft (21.2 m)
Longest span17 ft (5.2 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,357 (2022)
Projected traffic1,100 by 2042
Trucks21%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed19.9 mi (32 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—
NavigationNo navigation control on waterway

Frequently asked questions

When was Mn 56 over N Br Upper Iowa River built?

It was built in 1983, making it 42 years old in 2025.

What condition is Mn 56 over N Br Upper Iowa 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 August 2023.

How much traffic does Mn 56 over N Br Upper Iowa River carry?

About 1,357 vehicles per day (2022 count), of which roughly 21% are trucks.

How long is Mn 56 over N Br Upper Iowa River?

The structure is 70 ft (21.2 m) long with a longest span of 17 ft (5.2 m).

Who owns Mn 56 over N Br Upper Iowa River?

It is owned by the State Highway Agency.