SR 55
Carrying SR 55 over S405-N55 CONNECTOR
12-ORA-055-R5.89-CMS, Orange, California
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
SR 55 in Orange, California sits above 37% of rated California bridges on inventory load rating (32 t), while its 1966 build year is earlier than 69% of Orange's recorded-year cohort (1,164 bridges).
SR 55 in Orange, California is rated Poor in the FHWA's 2024 National Bridge Inventory. Built in 1966, 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:55 0423
INTERSTATE-ERA · CONCRETE · MULTI-SPAN · DECK-LED · HEAVY-ADT · STANDARD-LOAD · CAT-POOR
- INTERSTATE-ERA 1950–1979
- CONCRETE Concrete
- MULTI-SPAN 3 spans
- DECK-LED Deck-led
- HEAVY-ADT Heavy ADT
- STANDARD-LOAD Standard 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: SR 55
The SR 55 bridge in Orange, California carries SR 55 over S405-N55 CONNECTOR. It was built in 1966, making it 60 years old today. It was last reconstructed in 1970, extending its service life. The structure is built primarily of concrete continuous and spans 3 sections, stretching 42.4 meters (139 feet) end to end. Daily traffic averages 167,000 vehicles, placing it in the heavily-trafficked tier of California bridges. It is owned and maintained by State Highway Agency.
The latest FHWA inspection records show a deck rating of 4/9, superstructure at 7/9, substructure at 7/9. The weakest component sits in poor condition. Because at least one major component scores 4 or lower, this bridge falls in FHWA's Poor condition category. That category is not a closure order.
How SR 55 compares
Age against the county: built in 1966, earlier than 808 of Orange's 1,164 bridges with a recorded construction year (69%), against a county median build year of 1976. 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).
SR 55 vs every rated California bridge
Inventory load rating (metric tons), FHWA NBI, this state
32 Top 63% higher than 37% 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.
Orange inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 1,164 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
- 1966
- Last Reconstructed
- 1970
- Material
- Concrete Continuous
- Number of Spans
- 3
- Structure Length
- 42.4 m (139 ft)
- Deck Width
- 48.2 m (158 ft)
- Owner
- State Highway Agency
- Avg Daily Traffic
- 167,000 vehicles/day
- Structure Number
- 55 0423
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) is in good condition (7/9), showing no significant deterioration.
- • The substructure (piers and abutments) is in good condition (7/9), showing no significant deterioration.
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
SR 55 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 SR 55 against other structures in Orange 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 SR 55?
SR 55 in Orange, California has a deck rating of 4/9, superstructure rating of 7/9, and substructure rating of 7/9 on the FHWA's 0–9 scale.
How often is SR 55 inspected?
SR 55'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 167,000 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. SR 55 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 SR 55?
SR 55 has an NBI inventory load rating of 32.4 metric tons.
Who is responsible for maintaining SR 55?
SR 55 is owned and maintained by State Highway Agency.
How old is SR 55 and does age affect safety?
SR 55 was built in 1966, making it 60 years old and last reconstructed in 1970.
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.