DIABLO ROAD
Carrying DIABLO ROAD over SAN RAMON CREEK
0.2 MI WEST OF I-680, Contra Costa, California
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: DIABLO ROAD
The DIABLO ROAD bridge in Contra Costa, California carries DIABLO ROAD over SAN RAMON CREEK. It was built in 1966, making it 60 years old today. The structure is built primarily of steel continuous and spans 3 sections, stretching 34.0 meters (112 feet) end to end. Daily traffic averages 21,350 vehicles, placing it in the heavily-trafficked tier of California bridges. It is owned and maintained by City/Municipal Highway Agency.
The latest FHWA inspection records show a deck rating of 4/9, superstructure at 7/9, substructure at 6/9. 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. Its NBI inventory load rating is 23.7 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How DIABLO ROAD 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 How the historical reference is calculated.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
- 1966
- Material
- Steel Continuous
- Number of Spans
- 3
- Structure Length
- 34.0 m (112 ft)
- Deck Width
- 23.2 m (76 ft)
- Owner
- City/Municipal Highway Agency
- Avg Daily Traffic
- 21,350 vehicles/day
- Structure Number
- 28C0200
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗Condition Analysis
- • The deck (driving surface) rates poor at 4/9, advanced deterioration that should be prioritized for repair.
- • At 7/9, the superstructure (beams and supports above the deck) is in good shape and shows no significant wear.
- • The substructure (piers and abutments) rates fair at 6/9, minor deterioration that routine maintenance should address.
How to read this record
DIABLO ROAD 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 DIABLO ROAD against other structures in Contra Costa 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 DIABLO ROAD?
DIABLO ROAD in Contra Costa, California has a deck rating of 4/9, superstructure rating of 7/9, and substructure rating of 6/9 on the FHWA's 0–9 scale.
How often is DIABLO ROAD inspected?
DIABLO ROAD'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 21,350 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. DIABLO ROAD 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 DIABLO ROAD?
DIABLO ROAD has an NBI inventory load rating of 23.7 metric tons.
Who is responsible for maintaining DIABLO ROAD?
DIABLO ROAD is owned and maintained by City/Municipal Highway Agency.
How old is DIABLO ROAD and does age affect safety?
DIABLO ROAD was built in 1966, making it 60 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.