US Bridges

Csah 18 over Indian Slough

Fair

Goodhue County, Minnesota · 2.6 MI N of JCT TH 61 · Structure no. 25506

Built
1968
57 years old
Condition
Fair
inspected September 2023
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
342 ft
5 main spans
Daily traffic
6,400
2019 count
Owner
County
County Highway Agency

About this bridge

Csah 18 over Indian Slough is a steel continuous stringer/multi-beam or girder carrying Csah 18 over Indian Slough in Goodhue County, Minnesota. It was built in 1968, so it is 57 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 6,400 vehicles a day, projected to reach 6,900 by 2039. The structure is 342 ft (104.2 m) long and 40 ft wide. If it were closed, the detour would be 9.9 mi (16 km).

Location

Open in Google Maps
CarriesCsah 18
CrossesIndian Slough
Location2.6 MI N of JCT TH 61
RouteCounty Highway 18
CountyGoodhue County
StateMinnesota
Coordinates44.62798, -92.67176
Functional classUrban 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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating59.9 US tons
Inventory rating35.8 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans5
Design loadHS 20
Structure length342 ft (104.2 m)
Longest span72 ft (22 m)
Deck width40 ft (12.1 m)
Roadway width36 ft (11 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,400 (2019)
Projected traffic6,900 by 2039
Trucks—
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed9.9 mi (16 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty 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 Csah 18 over Indian Slough built?

It was built in 1968, making it 57 years old in 2025.

What condition is Csah 18 over Indian Slough 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 September 2023.

How much traffic does Csah 18 over Indian Slough carry?

About 6,400 vehicles per day (2019 count).

How long is Csah 18 over Indian Slough?

The structure is 342 ft (104.2 m) long with a longest span of 72 ft (22 m) and a deck 40 ft wide.

Who owns Csah 18 over Indian Slough?

It is owned by the County Highway Agency.