FHWA NBI 2024 Inspection record Public-domain dataset

STATE ROUTE 78

Carrying STATE ROUTE 78 over PALO VERDE OUTFALL

11-IMP-078-79.19, Imperial, California

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Poor
20 t Inventory load rating

Bridge Snapshot: STATE ROUTE 78

The STATE ROUTE 78 bridge in Imperial, California carries STATE ROUTE 78 over PALO VERDE OUTFALL. It was built in 1964, making it 62 years old today. The structure is built primarily of concrete continuous and spans 5 sections, stretching 66.1 meters (217 feet) end to end. Daily traffic averages 2,150 vehicles, placing it in the moderately-trafficked tier of California bridges. It is owned and maintained by State Highway Agency.

The latest FHWA inspection records show a deck rating of 4/9, superstructure at 7/9, substructure at 7/9. 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 20.4 metric tons.

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

How STATE ROUTE 78 compares

▼ 10.9
Load rating vs California average (31.3 t)
Bottom 13%
Lower load rating than 87% of California bridges
448
Bridges in Imperial · 39 in Poor condition
STATE ROUTE 78 20.4 t
California average 31.3 t

Live comparison across California.

Historical Sufficiency Rating

PlainBridge-computed
70.6 / 100 - historical 50–79.9 band
Structural adequacy /55
41.5
Serviceability /30
15.9
Essentiality /15
14.3
Special reductions
−1.0

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 How the historical reference is calculated.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
4/9
Poor (1–4)
Superstructure
7/9
Good (7–9)
Substructure
7/9
Good (7–9)
Inventory Load Rating
20.4 t
NBI inventory level (metric tons)
Overall Condition
Poor

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

Structural Details

Year Built
1964
Material
Concrete Continuous
Number of Spans
5
Structure Length
66.1 m (217 ft)
Deck Width
10.4 m (34 ft)
Owner
State Highway Agency
Avg Daily Traffic
2,150 vehicles/day
Structure Number
58 0299

Condition Analysis

  • At 4/9, the deck (driving surface) is in poor shape, with advanced wear flagged for priority 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) is in good condition (7/9), showing no significant deterioration.

How to read this record

STATE ROUTE 78 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 STATE ROUTE 78 against other structures in Imperial 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 78?

STATE ROUTE 78 in Imperial, California has a deck rating of 4/9, superstructure rating of 7/9, and substructure rating of 7/9 on the FHWA's 0–9 scale.

How often is STATE ROUTE 78 inspected?

STATE ROUTE 78'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 2,150 vehicles per day.

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

FHWA retired that reported status beginning with the 2018 archive. STATE ROUTE 78 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 STATE ROUTE 78?

STATE ROUTE 78 has an NBI inventory load rating of 20.4 metric tons.

Who is responsible for maintaining STATE ROUTE 78?

STATE ROUTE 78 is owned and maintained by State Highway Agency.

How old is STATE ROUTE 78 and does age affect safety?

STATE ROUTE 78 was built in 1964, making it 62 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.