US Bridges

Csah 31 over Rabbit Lake Narrows

Poor

Crow Wing County, Minnesota · 3.0 MI N of JCT TH 210-6 · Structure no. 18506

Built
1974
51 years old
Condition
Poor
inspected November 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
24 ft
1 main span
Daily traffic
1,300
2019 count
Owner
County
County Highway Agency

About this bridge

Csah 31 over Rabbit Lake Narrows is a steel stringer/multi-beam or girder carrying Csah 31 over Rabbit Lake Narrows in Crow Wing County, Minnesota. It was built in 1974, so it is 51 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 1,300 vehicles a day, projected to reach 1,250 by 2039. The structure is 24 ft (7.3 m) long and 33 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

CarriesCsah 31
CrossesRabbit Lake Narrows
Location3.0 MI N of JCT TH 210-6
RouteCounty Highway 31
Coordinates46.53054, -93.92743
Functional classRural Minor 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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, 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 protection8 Very GoodNo problems noted.
Last inspectionNovember 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 rating37.8 US tons
Inventory rating29.3 US tons

Structure

MaterialSteel
DeckWood or timber
Main spans1
Design loadHS 20
Structure length24 ft (7.3 m)
Longest span22 ft (6.7 m)
Deck width33 ft (10.1 m)
Roadway width31 ft (9.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,300 (2019)
Projected traffic1,250 by 2039
Trucks—
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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 (2026 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Csah 31 over Rabbit Lake Narrows built?

It was built in 1974, making it 51 years old in 2025.

What condition is Csah 31 over Rabbit Lake Narrows 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 November 2024.

How much traffic does Csah 31 over Rabbit Lake Narrows carry?

About 1,300 vehicles per day (2019 count).

How long is Csah 31 over Rabbit Lake Narrows?

The structure is 24 ft (7.3 m) long with a longest span of 22 ft (6.7 m) and a deck 33 ft wide.

Who owns Csah 31 over Rabbit Lake Narrows?

It is owned by the County Highway Agency.