STATE ROUTE 12
Carrying STATE ROUTE 12 over LAGUNA DE SANTA ROSA
04-SON-012-9.63-SEB, Sonoma, California
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: STATE ROUTE 12
The STATE ROUTE 12 bridge in Sonoma, California carries STATE ROUTE 12 over LAGUNA DE SANTA ROSA. It was built in 2017, making it 9 years old today. The structure is built primarily of prestressed concrete continuous and spans 3 sections, stretching 71.9 meters (236 feet) end to end. Daily traffic averages 23,050 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 5/9, superstructure at 7/9, substructure at 7/9. The weakest component sits in fair condition. No reported major component scores in the Poor range under the current federal condition thresholds. Its NBI inventory load rating is 32.4 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How STATE ROUTE 12 compares
Live comparison across California.
Historical Sufficiency Rating
PlainBridge-computedFHWA discontinued this calculated item; it does not determine current condition, funding eligibility, posting, or closure. How the historical reference is calculated.
Condition Ratings
Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.
Structural Details
- Year Built
- 2017
- Material
- Prestressed Concrete Continuous
- Number of Spans
- 3
- Structure Length
- 71.9 m (236 ft)
- Deck Width
- 17.7 m (58 ft)
- Owner
- State Highway Agency
- Avg Daily Traffic
- 23,050 vehicles/day
- Structure Number
- 20 0296
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗Condition Analysis
- • The deck (driving surface) is in fair condition (5/9), with minor deterioration that may require routine maintenance.
- • At 7/9, the superstructure (beams and supports above the deck) is in good shape and shows no significant wear.
- • At 7/9, the substructure (piers and abutments) is in good shape and shows no significant wear.
How to read this record
This page shows what the last federal inspection recorded, not whether STATE ROUTE 12 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 STATE ROUTE 12 against other structures in Sonoma 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 STATE ROUTE 12?
STATE ROUTE 12 in Sonoma, California has a deck rating of 5/9, superstructure rating of 7/9, and substructure rating of 7/9 on the FHWA's 0–9 scale.
How often is STATE ROUTE 12 inspected?
STATE ROUTE 12'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 23,050 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. STATE ROUTE 12 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 STATE ROUTE 12?
STATE ROUTE 12 has an NBI inventory load rating of 32.4 metric tons.
Who is responsible for maintaining STATE ROUTE 12?
STATE ROUTE 12 is owned and maintained by State Highway Agency.
How old is STATE ROUTE 12 and does age affect safety?
STATE ROUTE 12 was built in 2017, making it 9 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.
Every figure on PlainBridge is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.