N. ST. CHARLES
Carrying N. ST. CHARLES over LEMHI RIVER
0.4 N. 0.3 E. SALMON, Lemhi, Idaho
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
N. ST. CHARLES in Lemhi, Idaho sits above 6% of rated Idaho bridges on inventory load rating (16 t), while its 1948 build year is earlier than 96% of Lemhi's recorded-year cohort (112 bridges).
N. ST. CHARLES in Lemhi, Idaho is rated Poor in the FHWA's 2024 National Bridge Inventory. Built in 1948, it carries 3 rated components on the inspecting agency's 0-9 scale, and its weakest reported component scores 4. The lowest applicable rating sets the federal condition category, so this Poor result describes the weakest reported component rather than the structure as a whole. No NBI category is a closure decision or a live crossing-safety verdict.
NBI record plate
Structure ID:000000000032755
PRE-1950 · PRESTRESS · MULTI-SPAN · SUB-LED · LOCAL-ADT · LIGHT-LOAD · CAT-POOR
- PRE-1950 Pre-1950
- PRESTRESS Prestressed concrete
- MULTI-SPAN 2 spans
- SUB-LED Substructure-led
- LOCAL-ADT Local ADT
- LIGHT-LOAD Light load
- CAT-POOR Poor
Inspection-sheet codes from this record’s year, material family, spans, controlling component, ADT, inventory load, and NBI category, not a live closure verdict.
Bridge Snapshot: N. ST. CHARLES
The N. ST. CHARLES bridge in Lemhi, Idaho carries N. ST. CHARLES over LEMHI RIVER. It was built in 1948, making it 78 years old today. It was last reconstructed in 1965, extending its service life. The structure is built primarily of prestressed concrete and spans 2 sections, stretching 24.1 meters (79 feet) end to end. Daily traffic averages 310 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 6/9, substructure at 4/9. 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.
How N. ST. CHARLES compares
Age against the county: built in 1948, earlier than 107 of Lemhi's 112 bridges with a recorded construction year (96%), against a county median build year of 1991. Age is not a defect on its own, but it is the population from which future Poor ratings are drawn.
Live comparison across Idaho bridges with a recorded inventory load rating (4,574 of 4,616 rated).
N. ST. CHARLES vs every rated Idaho bridge
Inventory load rating (metric tons), FHWA NBI, this state
16 Top 94% higher than 6% of 4,574 bridges
rated Idaho bridges, bucketed by value
Each bar is a band; taller bars hold more bridges. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source FHWA National Bridge Inventory · August 2026
Condition Ratings
Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.
Reported 0–9 component ratings from the FHWA NBI. The highlighted component is the lowest reported input to this record’s current condition category; it is not a closure or live crossing-safety decision.
Lemhi inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 112 bridges in this county. Orthogonal to this structure's component profile above: a county catalog share, not a live crossing-safety verdict.
Structural Details
- Year Built
- 1948
- Last Reconstructed
- 1965
- Material
- Prestressed Concrete
- Number of Spans
- 2
- Structure Length
- 24.1 m (79 ft)
- Deck Width
- 4.9 m (16 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 310 vehicles/day
- Structure Number
- 000000000032755
Condition Analysis
- • The deck (driving surface) rates fair at 6/9, minor deterioration that routine maintenance should address.
- • At 6/9, the superstructure (beams and supports above the deck) shows fair condition, with minor wear flagged for upkeep.
- • The substructure (piers and abutments) rates poor at 4/9, with advanced deterioration recorded on the latest inspection.
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
N. ST. CHARLES 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 N. ST. CHARLES against other structures in Lemhi 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 N. ST. CHARLES?
N. ST. CHARLES in Lemhi, Idaho has a deck rating of 6/9, superstructure rating of 6/9, and substructure rating of 4/9 on the FHWA's 0–9 scale.
How often is N. ST. CHARLES inspected?
N. ST. CHARLES'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 310 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. N. ST. CHARLES 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 N. ST. CHARLES?
N. ST. CHARLES has an NBI inventory load rating of 16.3 metric tons.
Who is responsible for maintaining N. ST. CHARLES?
N. ST. CHARLES is owned and maintained by County Highway Agency.
How old is N. ST. CHARLES and does age affect safety?
N. ST. CHARLES was built in 1948, making it 78 years old and last reconstructed in 1965.
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.
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Send this source-bounded record or download its data card. An NBI condition category is not a closure or live crossing-safety verdict.
Every figure on PlainBridges is rendered directly from federal source data, no number is typed in by an editor. Component ratings, ADT, and condition category on this page are copied from the NBI record for this structure; no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2024 NBI release. NBI condition categories reflect the latest reported inventory record, not a live safety, closure, or travel decision.