2900N
Carrying 2900N over E.BRANCH BIG LOST RIVER
2.7 S. 0.8 E. MOORE, Butte, Idaho
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
2900N in Butte, Idaho sits above 37% of rated Idaho bridges on inventory load rating (28 t), while its 1920 build year is earlier than 94% of Butte's recorded-year cohort (32 bridges).
2900N in Butte, Idaho is rated Fair in the FHWA's 2024 National Bridge Inventory. Built in 1920, it carries 3 rated components on the inspecting agency's 0-9 scale, and its weakest reported component scores 6. The lowest applicable rating sets the federal condition category, so this Fair 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:000000000031530
PRE-1950 · PRESTRESS · SINGLE-SPAN · SUB-LED · LOCAL-ADT · STANDARD-LOAD · CAT-FAIR
- PRE-1950 Pre-1950
- PRESTRESS Prestressed concrete
- SINGLE-SPAN Single span
- SUB-LED Substructure-led
- LOCAL-ADT Local ADT
- STANDARD-LOAD Standard load
- CAT-FAIR Fair
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: 2900N
The 2900N bridge in Butte, Idaho carries 2900N over E.BRANCH BIG LOST RIVER. It was built in 1920, making it 106 years old today. It was last reconstructed in 1990, extending its service life. The structure is built primarily of prestressed concrete and spans 1 section, stretching 15.8 meters (52 feet) end to end. Daily traffic averages 160 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 7/9, superstructure at 7/9, substructure at 6/9. The weakest component sits in fair condition. All reported major components score above the Poor range.
How 2900N compares
Age against the county: built in 1920, earlier than 30 of Butte's 32 bridges with a recorded construction year (94%), against a county median build year of 1977. 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).
2900N vs every rated Idaho bridge
Inventory load rating (metric tons), FHWA NBI, this state
28 Top 63% higher than 37% 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.
Butte inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 32 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
- 1920
- Last Reconstructed
- 1990
- Material
- Prestressed Concrete
- Number of Spans
- 1
- Structure Length
- 15.8 m (52 ft)
- Deck Width
- 7.3 m (24 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 160 vehicles/day
- Structure Number
- 000000000031530
Condition Analysis
- • At 7/9, the deck (driving surface) is in good shape and shows no significant wear.
- • The superstructure (beams and supports above the deck) rates good at 7/9, with no significant deterioration on file.
- • The substructure (piers and abutments) rates fair at 6/9, minor deterioration that routine maintenance should address.
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
This page shows what the last federal inspection recorded, not whether 2900N 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 2900N against other structures in Butte 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 2900N?
2900N in Butte, Idaho has a deck rating of 7/9, superstructure rating of 7/9, and substructure rating of 6/9 on the FHWA's 0–9 scale.
How often is 2900N inspected?
2900N'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 160 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. 2900N 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 2900N?
2900N has an NBI inventory load rating of 28.1 metric tons.
Who is responsible for maintaining 2900N?
2900N is owned and maintained by County Highway Agency.
How old is 2900N and does age affect safety?
2900N was built in 1920, making it 106 years old and last reconstructed in 1990.
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.
Share this inspection record
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.