US Bridges

Csah 21 over Pike River

Poor

St. Louis County, Minnesota · 0.3 MI E of JCT TH 169 · Structure no. 7184

Built
1957
68 years old
Condition
Poor
inspected August 2024
Type
Channel Beam
Prestressed Concrete
Length
78 ft
3 main spans
Daily traffic
1,750
2019 count
Owner
County
County Highway Agency

About this bridge

Csah 21 over Pike River is a prestressed concrete channel beam carrying Csah 21 over Pike River in St. Louis County, Minnesota. It was built in 1957, so it is 68 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 1,750 vehicles a day, projected to reach 1,900 by 2039. The structure is 78 ft (23.8 m) long and 31 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesCsah 21
CrossesPike River
Location0.3 MI E of JCT TH 169
RouteCounty Highway 21
CountySt. Louis County
StateMinnesota
Coordinates47.63262, -92.42061
Functional classRural Minor Arterial

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.
Superstructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionAugust 2024
Inspection intervalevery 12 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating36.8 US tons
Inventory rating28.2 US tons

Structure

Structure typeChannel Beam
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans3
Design loadH 20
Structure length78 ft (23.8 m)
Longest span26 ft (7.8 m)
Deck width31 ft (9.6 m)
Roadway width30 ft (9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,750 (2019)
Projected traffic1,900 by 2039
Trucks—
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 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$1,000 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Csah 21 over Pike River built?

It was built in 1957, making it 68 years old in 2025.

What condition is Csah 21 over Pike 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 August 2024.

How much traffic does Csah 21 over Pike River carry?

About 1,750 vehicles per day (2019 count).

How long is Csah 21 over Pike River?

The structure is 78 ft (23.8 m) long with a longest span of 26 ft (7.8 m) and a deck 31 ft wide.

Who owns Csah 21 over Pike River?

It is owned by the County Highway Agency.