US Bridges

Csah 20 over Rum River

Poor

Mille Lacs County, Minnesota · 0.1 MI E of JCT TH 169 · Structure no. 48504

Built
1966
59 years old
Condition
Poor
inspected June 2024
Type
Stringer/Multi-beam or Girder
Steel Continuous
Length
111 ft
3 main spans
Daily traffic
520
2018 count
Owner
County
County Highway Agency

About this bridge

Csah 20 over Rum River is a steel continuous stringer/multi-beam or girder carrying Csah 20 over Rum River in Mille Lacs County, Minnesota. It was built in 1966, so it is 59 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 520 vehicles a day, projected to reach 415 by 2038. The structure is 111 ft (33.7 m) long and 32 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

Location

Open in Google Maps
CarriesCsah 20
CrossesRum River
Location0.1 MI E of JCT TH 169
RouteCounty Highway 20
CountyMille Lacs County
StateMinnesota
Coordinates45.95136, -93.65688
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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionJune 2024
Inspection intervalevery 12 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating50.2 US tons
Inventory rating30.1 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadH 20
Structure length111 ft (33.7 m)
Longest span42 ft (12.7 m)
Deck width32 ft (9.8 m)
Roadway width30 ft (9.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic520 (2018)
Projected traffic415 by 2038
Trucks—
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 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 20 over Rum River built?

It was built in 1966, making it 59 years old in 2025.

What condition is Csah 20 over Rum River 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 June 2024.

How much traffic does Csah 20 over Rum River carry?

About 520 vehicles per day (2018 count).

How long is Csah 20 over Rum River?

The structure is 111 ft (33.7 m) long with a longest span of 42 ft (12.7 m) and a deck 32 ft wide.

Who owns Csah 20 over Rum River?

It is owned by the County Highway Agency.