ROAD 20N24
Carrying ROAD 20N24 over PONDEROSA SPILLWAY
PONDEROSA RESERVOIR, Butte, California
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
ROAD 20N24 in Butte, California is rated Good in the FHWA's 2024 National Bridge Inventory.
Built in 1960, it carries 3 rated components on the inspecting agency's 0-9 scale, and its weakest reported component scores 7. The lowest applicable rating sets the federal condition category, so this Good 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:051153000001034
INTERSTATE-ERA · STEEL · MULTI-SPAN · TIED-CTRL · LOCAL-ADT · LOAD-UNK · CAT-GOOD
- INTERSTATE-ERA 1950–1979
- STEEL Steel
- MULTI-SPAN 2 spans
- TIED-CTRL Tied control
- LOCAL-ADT Local ADT
- LOAD-UNK Load unrated
- CAT-GOOD Good
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: ROAD 20N24
The ROAD 20N24 bridge in Butte, California carries ROAD 20N24 over PONDEROSA SPILLWAY. It was built in 1960, making it 66 years old today. It was last reconstructed in 2000, extending its service life. The structure is built primarily of steel and spans 2 sections, stretching 31.9 meters (105 feet) end to end. Daily traffic averages 50 vehicles, placing it in the lower-traffic tier of California bridges. It is owned and maintained by U.S. Forest Service.
The latest FHWA inspection records show a deck rating of 7/9, superstructure at 7/9, substructure at 7/9. The weakest component sits in good condition. No reported major component scores in the Poor range under the current federal condition thresholds.
How ROAD 20N24 compares
Age against the county: built in 1960, earlier than 224 of Butte's 437 bridges with a recorded construction year (51%), against a county median build year of 1961. Age is not a defect on its own, but it is the population from which future Poor ratings are drawn.
Live comparison across California bridges with a recorded inventory load rating (25,538 of 25,848 rated).
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
- 1960
- Last Reconstructed
- 2000
- Material
- Steel
- Number of Spans
- 2
- Structure Length
- 31.9 m (105 ft)
- Deck Width
- 6.1 m (20 ft)
- Owner
- U.S. Forest Service
- Avg Daily Traffic
- 50 vehicles/day
- Structure Number
- 051153000001034
Condition Analysis
- • The deck (driving surface) is in good condition (7/9), showing no significant deterioration.
- • The superstructure (beams and supports above the deck) is in good condition (7/9), showing no significant deterioration.
- • 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
This page shows what the last federal inspection recorded, not whether ROAD 20N24 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 ROAD 20N24 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 ROAD 20N24?
ROAD 20N24 in Butte, California has a deck rating of 7/9, superstructure rating of 7/9, and substructure rating of 7/9 on the FHWA's 0–9 scale.
How often is ROAD 20N24 inspected?
ROAD 20N24'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 50 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. ROAD 20N24 is currently shown as Good condition from its component ratings; that category is not a live closure or safety decision.
What is the inventory load rating for ROAD 20N24?
An inventory load rating is not recorded for ROAD 20N24.
Who is responsible for maintaining ROAD 20N24?
ROAD 20N24 is owned and maintained by U.S. Forest Service.
How old is ROAD 20N24 and does age affect safety?
ROAD 20N24 was built in 1960, making it 66 years old and last reconstructed in 2000.
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.