US Bridges

S 1 over Flint Creek

Fair

Granite County, Montana · 4M N Maxville · Structure no. P00019053+03701

Built
1931
94 years old, rebuilt 1986
Condition
Fair
inspected July 2024
Type
Tee Beam
Concrete
Length
115 ft
3 main spans
Daily traffic
1,144
2023 count
Owner
State
State Highway Agency

About this bridge

S 1 over Flint Creek is a concrete tee beam carrying S 1 over Flint Creek in Granite County, Montana. It was built in 1931 and reconstructed in 1986, so it is 94 years old, older than the Montana average of 47 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 5 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 1,144 vehicles a day, roughly 1% of them trucks, projected to reach 1,304 by 2043. The structure is 115 ft (35.1 m) long and 36 ft wide. If it were closed, the detour would be 29.8 mi (48 km).

Location

Open in Google Maps
CarriesS 1
CrossesFlint Creek
Location4M N Maxville
RouteState Highway 1
CountyGranite County
StateMontana
Coordinates46.52918, -113.22382
Functional classRural Minor Arterial

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionJuly 2024
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 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 rating34 US tons
Inventory rating26 US tons

Structure

Structure typeTee Beam
MaterialConcrete
DeckNot applicable
Main spans3
Design loadH 15
Structure length115 ft (35.1 m)
Longest span38 ft (11.6 m)
Deck width36 ft (11.1 m)
Roadway width33 ft (10.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,144 (2023)
Projected traffic1,304 by 2043
Trucks1%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed29.8 mi (48 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 1 over Flint Creek built?

It was built in 1931, making it 94 years old in 2025. It was reconstructed in 1986.

What condition is S 1 over Flint Creek 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 2024.

How much traffic does S 1 over Flint Creek carry?

About 1,144 vehicles per day (2023 count), of which roughly 1% are trucks.

How long is S 1 over Flint Creek?

The structure is 115 ft (35.1 m) long with a longest span of 38 ft (11.6 m) and a deck 36 ft wide.

Who owns S 1 over Flint Creek?

It is owned by the State Highway Agency.