US Bridges

S 80-13th ST over Missouri River

Poor

Chouteau County, Montana · Fort BENTON-13th ST · Structure no. P00080002+04331

Built
1962
63 years old
Condition
Poor
inspected May 2023
Type
Girder and Floorbeam System
Steel Continuous
Length
708 ft
4 main spans
Daily traffic
930
2023 count
Owner
State
State Highway Agency

About this bridge

S 80-13th ST over Missouri River is a steel continuous girder and floorbeam system carrying S 80-13th ST over Missouri River in Chouteau County, Montana. It was built in 1962, so it is 63 years old, older than the Montana average of 47 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 930 vehicles a day, roughly 8% of them trucks, projected to reach 977 by 2043. The structure is 708 ft (215.8 m) long and 28 ft wide. If it were closed, the detour would be 92 mi (148 km).

Location

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CarriesS 80-13th ST
CrossesMissouri River
LocationFort BENTON-13th ST
RouteState Highway 80
CountyChouteau County
StateMontana
Coordinates47.81501, -110.66715
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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMay 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 geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating45 US tons
Inventory rating27 US tons

Structure

Structure typeGirder and Floorbeam System
MaterialSteel Continuous
DeckConcrete, cast-in-place
Main spans4 (+2 approach)
Design loadHS 15
Structure length708 ft (215.8 m)
Longest span186 ft (56.7 m)
Deck width28 ft (8.5 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic930 (2023)
Projected traffic977 by 2043
Trucks8%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed92 mi (148 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState 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 S 80-13th ST over Missouri River built?

It was built in 1962, making it 63 years old in 2025.

What condition is S 80-13th ST over Missouri 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 May 2023.

How much traffic does S 80-13th ST over Missouri River carry?

About 930 vehicles per day (2023 count), of which roughly 8% are trucks.

How long is S 80-13th ST over Missouri River?

The structure is 708 ft (215.8 m) long with a longest span of 186 ft (56.7 m) and a deck 28 ft wide.

Who owns S 80-13th ST over Missouri River?

It is owned by the State Highway Agency.