OLD STATE ROUTE 99
Carrying OLD STATE ROUTE 99 over NORTH FARMDALE SLOUGH
0.2 MI NW/O E MISSION AV, Merced, California
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
OLD STATE ROUTE 99 in Merced, California sits above 16% of rated California bridges on inventory load rating (24 t), while its 1938 build year is earlier than 87% of Merced's recorded-year cohort (528 bridges).
OLD STATE ROUTE 99 in Merced, California is rated Fair in the FHWA's 2024 National Bridge Inventory. Built in 1938, it carries 1 rated component on the inspecting agency's 0-9 scale, and its weakest reported component scores 6. The lowest applicable rating sets the federal condition category, so this Fair 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:39C0395
PRE-1950 · CONCRETE · MULTI-SPAN · CULVERT-LED · LOCAL-ADT · STANDARD-LOAD · CAT-FAIR
- PRE-1950 Pre-1950
- CONCRETE Concrete
- MULTI-SPAN 3 spans
- CULVERT-LED Culvert-led
- LOCAL-ADT Local ADT
- STANDARD-LOAD Standard load
- CAT-FAIR Fair
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: OLD STATE ROUTE 99
The OLD STATE ROUTE 99 bridge in Merced, California carries OLD STATE ROUTE 99 over NORTH FARMDALE SLOUGH. It was built in 1938, making it 88 years old today. It was last reconstructed in 2005, extending its service life. The structure is built primarily of concrete continuous and spans 3 sections, stretching 8.2 meters (27 feet) end to end. Daily traffic averages 270 vehicles, placing it in the lower-traffic tier of California bridges. It is owned and maintained by County Highway Agency.
The latest FHWA inspection records show culvert at 6/9. The weakest component sits in fair condition. All reported major components score above the Poor range.
How OLD STATE ROUTE 99 compares
Age against the county: built in 1938, earlier than 457 of Merced's 528 bridges with a recorded construction year (87%), against a county median build year of 1966. 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).
OLD STATE ROUTE 99 vs every rated California bridge
Inventory load rating (metric tons), FHWA NBI, this state
24 Top 84% higher than 16% 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.
Merced inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 528 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
- 1938
- Last Reconstructed
- 2005
- Material
- Concrete Continuous
- Number of Spans
- 3
- Structure Length
- 8.2 m (27 ft)
- Deck Width
- 12.8 m (42 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 270 vehicles/day
- Structure Number
- 39C0395
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
This page shows what the last federal inspection recorded, not whether OLD STATE ROUTE 99 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 OLD STATE ROUTE 99 against other structures in Merced 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 OLD STATE ROUTE 99?
OLD STATE ROUTE 99 in Merced, California on the FHWA's 0–9 scale.
How often is OLD STATE ROUTE 99 inspected?
OLD STATE ROUTE 99'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 270 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. OLD STATE ROUTE 99 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 OLD STATE ROUTE 99?
OLD STATE ROUTE 99 has an NBI inventory load rating of 24.3 metric tons.
Who is responsible for maintaining OLD STATE ROUTE 99?
OLD STATE ROUTE 99 is owned and maintained by County Highway Agency.
How old is OLD STATE ROUTE 99 and does age affect safety?
OLD STATE ROUTE 99 was built in 1938, making it 88 years old and last reconstructed in 2005.
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.