US HIGHWAY 101 NB
Carrying US HIGHWAY 101 NB over TRAFFIC WAY
05-SLO-101-45.96-ATAS, San Luis Obispo, California
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
US HIGHWAY 101 NB in San Luis Obispo, California sits above 11% of rated California bridges on inventory load rating (20 t), while its 1956 build year is earlier than 71% of San Luis Obispo's recorded-year cohort (401 bridges).
US HIGHWAY 101 NB in San Luis Obispo, California is rated Poor in the FHWA's 2024 National Bridge Inventory. Built in 1956, 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:49 0152R
INTERSTATE-ERA · STEEL · SINGLE-SPAN · TIED-CTRL · HEAVY-ADT · STANDARD-LOAD · CAT-POOR
- INTERSTATE-ERA 1950–1979
- STEEL Steel
- SINGLE-SPAN Single span
- TIED-CTRL Tied control
- 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: US HIGHWAY 101 NB
The US HIGHWAY 101 NB bridge in San Luis Obispo, California carries US HIGHWAY 101 NB over TRAFFIC WAY. It was built in 1956, making it 70 years old today. It was last reconstructed in 2012, extending its service life. The structure is built primarily of steel and spans 1 section, stretching 40.0 meters (131 feet) end to end. Daily traffic averages 30,000 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 4/9, substructure at 7/9. The weakest component sits in poor condition. A component scored 4 or below, placing this bridge in the federal Poor condition category rather than declaring it unsafe or closed.
How US HIGHWAY 101 NB compares
Age against the county: built in 1956, earlier than 283 of San Luis Obispo's 401 bridges with a recorded construction year (71%), against a county median build year of 1964. 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).
US HIGHWAY 101 NB vs every rated California bridge
Inventory load rating (metric tons), FHWA NBI, this state
20 Top 89% higher than 11% 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.
San Luis Obispo inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 401 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
- 1956
- Last Reconstructed
- 2012
- Material
- Steel
- Number of Spans
- 1
- Structure Length
- 40.0 m (131 ft)
- Deck Width
- 12.5 m (41 ft)
- Owner
- State Highway Agency
- Avg Daily Traffic
- 30,000 vehicles/day
- Structure Number
- 49 0152R
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 poor condition (4/9), showing advanced deterioration on the inspecting agency's 0-9 scale.
- • 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
US HIGHWAY 101 NB 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 US HIGHWAY 101 NB against other structures in San Luis Obispo 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 US HIGHWAY 101 NB?
US HIGHWAY 101 NB in San Luis Obispo, California has a deck rating of 4/9, superstructure rating of 4/9, and substructure rating of 7/9 on the FHWA's 0–9 scale.
How often is US HIGHWAY 101 NB inspected?
US HIGHWAY 101 NB'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 30,000 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. US HIGHWAY 101 NB 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 US HIGHWAY 101 NB?
US HIGHWAY 101 NB has an NBI inventory load rating of 20.4 metric tons.
Who is responsible for maintaining US HIGHWAY 101 NB?
US HIGHWAY 101 NB is owned and maintained by State Highway Agency.
How old is US HIGHWAY 101 NB and does age affect safety?
US HIGHWAY 101 NB was built in 1956, making it 70 years old and last reconstructed in 2012.
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.