US Bridges

Csah 20 over I 90

Poor

Mower County, Minnesota · 3.8 MI E of JCT TH 56 · Structure no. 9506

Built
1960
65 years old
Condition
Poor
inspected October 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
201 ft
4 main spans
Daily traffic
250
2016 count
Owner
State
State Highway Agency

About this bridge

Csah 20 over I 90 is a steel continuous stringer/multi-beam or girder carrying Csah 20 over I 90 in Mower County, Minnesota. It was built in 1960, so it is 65 years old, older than the Minnesota average of 38.5 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 250 vehicles a day, projected to reach 250 by 2039. The structure is 201 ft (61.3 m) long and 35 ft wide. If it were closed, the detour would be 14.3 mi (23 km).

Location

Open in Google Maps
CarriesCsah 20
CrossesI 90
Location3.8 MI E of JCT TH 56
RouteCounty Highway 20
CountyMower County
StateMinnesota
Coordinates43.67362, -92.79411
Functional classRural Major Collector

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Deck4 PoorAdvanced section loss, deterioration, spalling or scour.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionOctober 2024
Inspection intervalevery 12 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating57.4 US tons
Inventory rating34.4 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans4
Design loadHS 20
Structure length201 ft (61.3 m)
Longest span66 ft (20 m)
Deck width35 ft (10.8 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic250 (2016)
Projected traffic250 by 2039
Trucks—
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesHighway
Detour if closed14.3 mi (23 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$976 million
NavigationNot applicable (no waterway)

Frequently asked questions

When was Csah 20 over I 90 built?

It was built in 1960, making it 65 years old in 2025.

What condition is Csah 20 over I 90 in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in October 2024.

How much traffic does Csah 20 over I 90 carry?

About 250 vehicles per day (2016 count).

How long is Csah 20 over I 90?

The structure is 201 ft (61.3 m) long with a longest span of 66 ft (20 m) and a deck 35 ft wide.

Who owns Csah 20 over I 90?

It is owned by the State Highway Agency.