S 359
Carrying S 359 over JEFFERSON RIVER
JEFFERSON ISLAND, Madison, Montana
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: S 359
The S 359 bridge in Madison, Montana carries S 359 over JEFFERSON RIVER. It was built in 1967, making it 59 years old today. The structure is built primarily of prestressed concrete and spans 3 sections, stretching 88.1 meters (289 feet) end to end. Daily traffic averages 1,402 vehicles, placing it in the moderately-trafficked tier of Montana bridges. It is owned and maintained by State Highway Agency.
The latest FHWA inspection records show a deck rating of 6/9, superstructure at 7/9, substructure at 7/9. The weakest component sits in fair condition. No reported major component scores in the Poor range under the current federal condition thresholds. Its NBI inventory load rating is 25.4 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How S 359 compares
Live comparison across Montana.
Historical Sufficiency Rating
PlainBridge-computedFHWA discontinued this calculated item; it does not determine current condition, funding eligibility, posting, or closure. How the historical reference is calculated.
Condition Ratings
Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.
Structural Details
- Year Built
- 1967
- Material
- Prestressed Concrete
- Number of Spans
- 3
- Structure Length
- 88.1 m (289 ft)
- Deck Width
- 10.1 m (33 ft)
- Owner
- State Highway Agency
- Avg Daily Traffic
- 1,402 vehicles/day
- Structure Number
- S00359002+02661
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗Condition Analysis
- • The deck (driving surface) rates fair at 6/9, minor deterioration that routine maintenance should address.
- • At 7/9, the superstructure (beams and supports above the deck) is in good shape and shows no significant wear.
- • At 7/9, the substructure (piers and abutments) is in good shape and shows no significant wear.
How to read this record
This page shows what the last federal inspection recorded, not whether S 359 is safe to cross today. Here is how to use it.
- NBI condition ratings reflect the latest record in this annual dataset, not a live status. Current routine inspection intervals are risk-based.
- Learn how the 0–9 condition scale and Good/Fair/Poor categories are defined. How condition ratings work
- Compare S 359 against other structures in Madison and across Montana. Montana bridges
- Noticed visible damage or a safety concern? Report it to the agency that owns the bridge, or call 911 in an emergency. How to report a bridge
Condition codes come straight from the FHWA National Bridge Inventory and are not a real-time safety judgment. Only the owning agency, a state DOT, county, or other owner, can post, restrict, or close a bridge.
Frequently Asked Questions
What do the condition ratings mean for S 359?
S 359 in Madison, Montana has a deck rating of 6/9, superstructure rating of 7/9, and substructure rating of 7/9 on the FHWA's 0–9 scale.
How often is S 359 inspected?
S 359's responsible agency sets its routine interval under FHWA's risk-based inspection rules; this page does not expose the scheduled interval. It carries about 1,402 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. S 359 is currently shown as Fair condition from its component ratings; that category is not a live closure or safety decision.
What is the inventory load rating for S 359?
S 359 has an NBI inventory load rating of 25.4 metric tons.
Who is responsible for maintaining S 359?
S 359 is owned and maintained by State Highway Agency.
How old is S 359 and does age affect safety?
S 359 was built in 1967, making it 59 years old.
Disclaimer: Bridge condition data is from the FHWA NBI and reflects the last reported inspection. A Poor condition rating is not a live declaration that a bridge is closed or unsafe for travel. For current closure, posting, or safety information, contact the responsible transportation agency.
Every figure on PlainBridge is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.