OLD MIL. RR GRADE
Carrying OLD MIL. RR GRADE over TROUT CREEK
0.9N 3.1W CALDER, Shoshone, Idaho
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: OLD MIL. RR GRADE
The OLD MIL. RR GRADE bridge in Shoshone, Idaho carries OLD MIL. RR GRADE over TROUT CREEK. It was built in 1912, making it 114 years old today. It was last reconstructed in 1991, extending its service life. The structure is built primarily of steel and spans 1 section, stretching 27.1 meters (89 feet) end to end. Daily traffic averages 15 vehicles, placing it in the lower-traffic tier of Idaho bridges. It is owned and maintained by County Highway Agency.
The latest FHWA inspection records show a deck rating of 6/9, superstructure at 5/9, substructure at 3/9. The weakest component sits in poor condition. At least one major component here scores 4 or below, which produces a Poor condition classification under FHWA's current reporting rules. Its NBI inventory load rating is 6.4 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How OLD MIL. RR GRADE compares
Live comparison across Idaho.
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 How the historical reference is calculated.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
- 1912
- Last Reconstructed
- 1991
- Material
- Steel
- Number of Spans
- 1
- Structure Length
- 27.1 m (89 ft)
- Deck Width
- 5.0 m (16 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 15 vehicles/day
- Structure Number
- 000000000037085
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.
- • The superstructure (beams and supports above the deck) is in fair condition (5/9), with minor deterioration that may require routine maintenance.
- • The substructure (piers and abutments) rates poor at 3/9, advanced deterioration that should be prioritized for repair.
How to read this record
OLD MIL. RR GRADE is in the federal Poor condition category. That is a component-based result, not a closure order.
- NBI condition ratings reflect the latest record in this annual dataset, not a live status. Current routine inspection intervals are risk-based.
- Understand what Poor condition does and does not mean before drawing conclusions. Poor condition explained
- Compare OLD MIL. RR GRADE against other structures in Shoshone and across Idaho. Idaho 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 OLD MIL. RR GRADE?
OLD MIL. RR GRADE in Shoshone, Idaho has a deck rating of 6/9, superstructure rating of 5/9, and substructure rating of 3/9 on the FHWA's 0–9 scale.
How often is OLD MIL. RR GRADE inspected?
OLD MIL. RR GRADE'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 15 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. OLD MIL. RR GRADE is currently shown as Poor condition from its component ratings; that category is not a live closure or safety decision.
What is the inventory load rating for OLD MIL. RR GRADE?
OLD MIL. RR GRADE has an NBI inventory load rating of 6.4 metric tons.
Who is responsible for maintaining OLD MIL. RR GRADE?
OLD MIL. RR GRADE is owned and maintained by County Highway Agency.
How old is OLD MIL. RR GRADE and does age affect safety?
OLD MIL. RR GRADE was built in 1912, making it 114 years old and last reconstructed in 1991.
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.