FHWA NBI 2024 Inspection record Public-domain dataset

IRON MOUNTAIN ROAD

Carrying IRON MOUNTAIN ROAD over FLAT CREEK

IRON MTN RD 3KM N.SR 299, Shasta, California

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Good
32 t Inventory load rating

Bridge Snapshot: IRON MOUNTAIN ROAD

The IRON MOUNTAIN ROAD bridge in Shasta, California carries IRON MOUNTAIN ROAD over FLAT CREEK. It was built in 1994, making it 32 years old today. The structure is built primarily of concrete and spans 1 section, stretching 20.5 meters (67 feet) end to end. Daily traffic averages 114 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 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 32.4 metric tons.

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

How IRON MOUNTAIN ROAD compares

▲ 1.1
Load rating vs California average (31.3 t)
Bottom 41%
Lower load rating than 59% of California bridges
500
Bridges in Shasta · 10 in Poor condition
IRON MOUNTAIN ROAD 32.4 t
California average 31.3 t

Live comparison across California.

Historical Sufficiency Rating

PlainBridge-computed
99.0 / 100 - historical 80–100 band
Structural adequacy /55
55.0
Serviceability /30
29.0
Essentiality /15
15.0
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 How the historical reference is calculated.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
32.4 t
NBI inventory level (metric tons)
Overall Condition
Good

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

Structural Details

Year Built
1994
Material
Concrete
Number of Spans
1
Structure Length
20.5 m (67 ft)
Deck Width
8.5 m (28 ft)
Owner
County Highway Agency
Avg Daily Traffic
114 vehicles/day
Structure Number
06C0021

Condition Analysis

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

How to read this record

This page shows what the last federal inspection recorded, not whether IRON MOUNTAIN ROAD 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 IRON MOUNTAIN ROAD against other structures in Shasta 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 IRON MOUNTAIN ROAD?

IRON MOUNTAIN ROAD in Shasta, 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 IRON MOUNTAIN ROAD inspected?

IRON MOUNTAIN 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 114 vehicles per day.

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

FHWA retired that reported status beginning with the 2018 archive. IRON MOUNTAIN ROAD 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 IRON MOUNTAIN ROAD?

IRON MOUNTAIN ROAD has an NBI inventory load rating of 32.4 metric tons.

Who is responsible for maintaining IRON MOUNTAIN ROAD?

IRON MOUNTAIN ROAD is owned and maintained by County Highway Agency.

How old is IRON MOUNTAIN ROAD and does age affect safety?

IRON MOUNTAIN ROAD was built in 1994, making it 32 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.