US Bridges

S 1 over RR

Good

Deer Lodge County, Montana · 6M S Warm Springs · Structure no. P00019000+03001

Built
1964
61 years old
Condition
Good
inspected June 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
151 ft
3 main spans
Daily traffic
4,640
2023 count
Owner
State
State Highway Agency

About this bridge

S 1 over RR is a prestressed concrete stringer/multi-beam or girder carrying S 1 over RR in Deer Lodge County, Montana. It was built in 1964, so it is 61 years old, older than the Montana average of 47 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 4,640 vehicles a day, roughly 2% of them trucks, projected to reach 4,872 by 2043. The structure is 151 ft (46 m) long and 41 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesS 1
CrossesRR
Location6M S Warm Springs
RouteState Highway 1
StateMontana
Coordinates46.09554, -112.79903
Functional classRural Minor Arterial

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Last inspectionJune 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Approach roadway alignment8: Equal to present desirable criteria
Operating rating44 US tons
Inventory rating30 US tons

Structure

MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length151 ft (46 m)
Longest span50 ft (15.2 m)
Deck width41 ft (12.4 m)
Roadway width38 ft (11.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,640 (2023)
Projected traffic4,872 by 2043
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesRailroad
Detour if closed1.2 mi (2 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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was S 1 over RR built?

It was built in 1964, making it 61 years old in 2025.

What condition is S 1 over RR in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in June 2024.

How much traffic does S 1 over RR carry?

About 4,640 vehicles per day (2023 count), of which roughly 2% are trucks.

How long is S 1 over RR?

The structure is 151 ft (46 m) long with a longest span of 50 ft (15.2 m) and a deck 41 ft wide.

Who owns S 1 over RR?

It is owned by the State Highway Agency.