FHWA NBI 2024 Inspection record Public-domain dataset

ALDERBROOK DR

Carrying ALDERBROOK DR over SANTA ROSA CREEK

NEAR 4TH STREET, Sonoma, California

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Good
46 t Inventory load rating

Bridge Snapshot: ALDERBROOK DR

The ALDERBROOK DR bridge in Sonoma, California carries ALDERBROOK DR over SANTA ROSA CREEK. It was built in 1979, making it 47 years old today. The structure is built primarily of concrete continuous and spans 3 sections, stretching 31.1 meters (102 feet) end to end. Daily traffic averages 1,000 vehicles, placing it in the lower-traffic tier of California bridges. It is owned and maintained by City/Municipal Highway Agency.

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. All reported major components score above the Poor range. Its NBI inventory load rating is 45.7 metric tons.

Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.

How ALDERBROOK DR compares

▲ 14.4
Load rating vs California average (31.3 t)
Top 8%
Higher load rating than 92% of California bridges
613
Bridges in Sonoma · 37 in Poor condition
ALDERBROOK DR 45.7 t
California average 31.3 t

Live comparison across California.

Historical Sufficiency Rating

PlainBridge-computed
91.9 / 100 - historical 80–100 band
Structural adequacy /55
55.0
Serviceability /30
22.2
Essentiality /15
14.7
Special reductions
0

FHWA discontinued this calculated item; it does not determine current condition, funding eligibility, posting, or closure. How the historical reference is calculated.

Condition Ratings

Deck
7/9
Good (7–9)
Superstructure
7/9
Good (7–9)
Substructure
7/9
Good (7–9)
Inventory Load Rating
45.7 t
NBI inventory level (metric tons)
Overall Condition
Good

Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.

Structural Details

Year Built
1979
Material
Concrete Continuous
Number of Spans
3
Structure Length
31.1 m (102 ft)
Deck Width
11.0 m (36 ft)
Owner
City/Municipal Highway Agency
Avg Daily Traffic
1,000 vehicles/day
Structure Number
20C0189

Condition Analysis

  • At 7/9, the deck (driving surface) is in good shape and shows no significant wear.
  • The superstructure (beams and supports above the deck) rates good at 7/9, with no significant deterioration on file.
  • The substructure (piers and abutments) is in good condition (7/9), showing no significant deterioration.

How to read this record

This page shows what the last federal inspection recorded, not whether ALDERBROOK DR 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 ALDERBROOK DR 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 ALDERBROOK DR?

ALDERBROOK DR in Sonoma, 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 ALDERBROOK DR inspected?

ALDERBROOK DR'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 1,000 vehicles per day.

What does “structurally deficient” mean in older bridge reports?

FHWA retired that reported status beginning with the 2018 archive. ALDERBROOK DR 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 ALDERBROOK DR?

ALDERBROOK DR has an NBI inventory load rating of 45.7 metric tons.

Who is responsible for maintaining ALDERBROOK DR?

ALDERBROOK DR is owned and maintained by City/Municipal Highway Agency.

How old is ALDERBROOK DR and does age affect safety?

ALDERBROOK DR was built in 1979, making it 47 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.

Data sourced from the Federal Highway Administration National Bridge Inventory. See our methodology for details. Retrieved and formatted by PlainBridges

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.