US Bridges

M 20 over Unnamed Stream

Good

Rock County, Minnesota · 0.04 MI SE of Koehn Ave · Structure no. 67K46

Built
2019
6 years old
Condition
Good
inspected November 2023
Type
Culvert
Concrete
Length
39 ft
2 main spans
Daily traffic
1
2019 count
Owner
City
City or Municipal Highway Agency

About this bridge

M 20 over Unnamed Stream is a concrete culvert carrying M 20 over Unnamed Stream in Rock County, Minnesota. It was built in 2019, so it is 6 years old, younger than the Minnesota average of 38.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 1 vehicles a day, projected to reach 1 by 2039. The structure is 39 ft (12 m) long. If it were closed, the detour would be 123 mi (198 km).

Location

Open in Google Maps
CarriesM 20
CrossesUnnamed Stream
Location0.04 MI SE of Koehn Ave
RouteCity Street 20
CountyRock County
StateMinnesota
Coordinates43.64188, -96.22668
Functional classRural Local

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Channel and channel protection8 Very GoodNo problems noted.
Culvert8 Very GoodNo problems noted.
Last inspectionNovember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating46.4 US tons
Inventory rating35.7 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans2
Design loadHL 93
Structure length39 ft (12 m)
Longest span20 ft (6 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1 (2019)
Projected traffic1 by 2039
Trucks—
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed123 mi (198 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was M 20 over Unnamed Stream built?

It was built in 2019, making it 6 years old in 2025.

What condition is M 20 over Unnamed Stream in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in November 2023.

How much traffic does M 20 over Unnamed Stream carry?

About 1 vehicles per day (2019 count).

How long is M 20 over Unnamed Stream?

The structure is 39 ft (12 m) long with a longest span of 20 ft (6 m).

Who owns M 20 over Unnamed Stream?

It is owned by the City or Municipal Highway Agency.