SKYWAY
Carrying SKYWAY over MAGALIA RESERVOIR SPILWY
AT MAGALIA, Butte, California
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
SKYWAY in Butte, California sits above 97% of rated California bridges on inventory load rating (57 t), while its 1975 build year is earlier than 19% of Butte's recorded-year cohort (437 bridges).
SKYWAY in Butte, California is rated Poor in the FHWA's 2024 National Bridge Inventory. Built in 1975, 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 CA:12C0395
INTERSTATE-ERA · CONCRETE · MULTI-SPAN · DECK-LED · HEAVY-ADT · HEAVY-LOAD · CAT-POOR
- INTERSTATE-ERA 1950–1979
- CONCRETE Concrete
- MULTI-SPAN 2 spans
- DECK-LED Deck-led
- HEAVY-ADT Heavy ADT
- HEAVY-LOAD Heavy 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: SKYWAY
The SKYWAY bridge in Butte, California carries SKYWAY over MAGALIA RESERVOIR SPILWY. It was built in 1975, making it 51 years old today. The structure is built primarily of concrete continuous and spans 2 sections, stretching 48.8 meters (160 feet) end to end. Daily traffic averages 13,516 vehicles, placing it in the heavily-trafficked tier of California bridges. It is owned and maintained by County Highway Agency.
The latest FHWA inspection records show a deck rating of 4/9, superstructure at 5/9, substructure at 7/9. 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 SKYWAY compares
Age against the county: built in 1975, earlier than 85 of Butte's 437 bridges with a recorded construction year (19%), against a county median build year of 1961. This is one of the newer structures in its county.
Live comparison across California bridges with a recorded inventory load rating (25,538 of 25,848 rated).
SKYWAY vs every rated California bridge
Inventory load rating (metric tons), FHWA NBI, this state
57 Top 3% higher than 97% of 25,538 bridges
rated California 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 437 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
- 1975
- Material
- Concrete Continuous
- Number of Spans
- 2
- Structure Length
- 48.8 m (160 ft)
- Deck Width
- 10.3 m (34 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 13,516 vehicles/day
- Structure Number
- 12C0395
Condition Analysis
- • At 4/9, the deck (driving surface) is in poor shape, with advanced wear on file for this vintage.
- • The superstructure (beams and supports above the deck) rates fair at 5/9, minor deterioration that routine maintenance should address.
- • The substructure (piers and abutments) rates good at 7/9, with no significant deterioration on file.
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
SKYWAY 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 SKYWAY against other structures in Butte and across California. California 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 SKYWAY?
SKYWAY in Butte, California has a deck rating of 4/9, superstructure rating of 5/9, and substructure rating of 7/9 on the FHWA's 0–9 scale.
How often is SKYWAY inspected?
SKYWAY'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 13,516 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. SKYWAY 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 SKYWAY?
SKYWAY has an NBI inventory load rating of 57.0 metric tons.
Who is responsible for maintaining SKYWAY?
SKYWAY is owned and maintained by County Highway Agency.
How old is SKYWAY and does age affect safety?
SKYWAY was built in 1975, making it 51 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.
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.