US Bridges

Csah 4 over Rum River

Fair

Mille Lacs County, Minnesota · 0.2 MI N of JCT Csah 8 · Structure no. 48522

Built
1980
45 years old
Condition
Fair
inspected July 2023
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
279 ft
3 main spans
Daily traffic
810
2018 count
Owner
County
County Highway Agency

About this bridge

Csah 4 over Rum River is a prestressed concrete stringer/multi-beam or girder carrying Csah 4 over Rum River in Mille Lacs County, Minnesota. It was built in 1980, so it is 45 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 810 vehicles a day, projected to reach 790 by 2038. The structure is 279 ft (85.1 m) long and 50 ft wide. If it were closed, the detour would be 8.1 mi (13 km).

Location

Open in Google Maps
CarriesCsah 4
CrossesRum River
Location0.2 MI N of JCT Csah 8
RouteCounty Highway 4
CountyMille Lacs County
StateMinnesota
Coordinates45.7021, -93.58521
Functional classRural Major Collector

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.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry8: Equal to present desirable criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating55.8 US tons
Inventory rating33.5 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length279 ft (85.1 m)
Longest span91 ft (27.7 m)
Deck width50 ft (15.2 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic810 (2018)
Projected traffic790 by 2038
Trucks—
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed8.1 mi (13 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 4 over Rum River built?

It was built in 1980, making it 45 years old in 2025.

What condition is Csah 4 over Rum 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 July 2023.

How much traffic does Csah 4 over Rum River carry?

About 810 vehicles per day (2018 count).

How long is Csah 4 over Rum River?

The structure is 279 ft (85.1 m) long with a longest span of 91 ft (27.7 m) and a deck 50 ft wide.

Who owns Csah 4 over Rum River?

It is owned by the County Highway Agency.