Structure 23 0228 · Solano County, CA

State Route 12 over Alonzo Drain

Carries State Route 12 over Alonzo Drain, 04-sol-012-l2.94-frfd.

Overall conditionPoor

Set by its lowest-rated component: Culvert at 4 of 9.

How ratings work
Culvertsets the rating4/9 · Poor
Channelnot part of overall9/9 · Excellent
0 failed4 poor6 fair9 excellent

Elevation

Side view, colored by inspection rating
CAR · 15 FT66 FT ACROSS25 FT0ELEVATION · LENGTHS TO SCALE
Culvert 4/9

A culvert 66 ft across with 6 openings. Lengths and the car on the deck are drawn to the same scale. Each part is colored by its latest inspection rating. The inventory records lengths but not heights, so those are drawn as typical for a culvert.

Built198046 years old
Length65.6 ft20 m
Daily traffic40,500counted 2019
Last inspectedMarch 2024every 24 months

Location

StateCalifornia
CountySolano
Location04-sol-012-l2.94-frfd
CarriesState Route 12
CrossesAlonzo Drain
Coordinates38.24006, -122.07127

Physical Characteristics

MaterialConcrete Continuous
DesignCulvert
Total Length65.6 ft (20 m)
Max Span10.2 ft (3.1 m)
Deck Width98.8 ft (30.1 m)
Deck Area602 sq m
Main Spans6
Year Built1980

Traffic

Avg Daily Traffic40,500 (2019)
Truck Traffic5%
Lanes On Bridge4

Inspection & Ownership

Last InspectionMarch 2024
Inspection FrequencyEvery 24 months
OwnerState Highway Agency
Historical SignificanceBridge is not eligible for the National Register
Scour Critical8 — Stable, low risk
Structure Number23 0228

How Bridge Ratings Work

Inspectors rate each major part of a bridge (the deck you drive on, the superstructure of beams that holds it up, and the substructure of piers and abutments beneath) on a 0–9 scale. A bridge's overall condition is its lowest of those ratings, so one deteriorated component makes the whole bridge "poor."

0Failed
1Imminent failure
2Critical
3Serious
4Poor
5Fair
6Satisfactory
7Good
8Very good
9Excellent
Good · lowest component 7–9
Fair · lowest component 5–6
Poor · lowest component 0–4

A poor rating is not a closure. It means the bridge is flagged for priority repair or replacement; bridges judged unsafe are closed or posted with weight limits. The waterway (channel) rating is reported, but it does not count toward the overall classification.

Nearby Bridges