FHWA NBI 2024 Inspection record Public-domain dataset

IRR - SR 480

Carrying IRR - SR 480 over MISSOURI RIVER

9M SW BROCKTON, Richland, Montana

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Fair
24 t Inventory load rating

Bridge Snapshot: IRR - SR 480

The IRR - SR 480 bridge in Richland, Montana carries IRR - SR 480 over MISSOURI RIVER. It was built in 1968, making it 58 years old today. The structure is built primarily of steel continuous and spans 4 sections, stretching 322.1 meters (1057 feet) end to end. Daily traffic averages 134 vehicles, placing it in the lower-traffic tier of Montana bridges. It is owned and maintained by State Highway Agency.

The latest FHWA inspection records show a deck rating of 6/9, superstructure at 5/9, substructure at 6/9. The weakest component sits in fair condition. All reported major components score above the Poor range. Its NBI inventory load rating is 23.6 metric tons.

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

How IRR - SR 480 compares

▼ 7.1
Load rating vs Montana average (30.7 t)
Bottom 25%
Lower load rating than 75% of Montana bridges
96
Bridges in Richland · 3 in Poor condition
IRR - SR 480 23.6 t
Montana average 30.7 t

Live comparison across Montana.

Historical Sufficiency Rating

PlainBridge-computed
75.8 / 100 - historical 50–79.9 band
Structural adequacy /55
36.5
Serviceability /30
29.0
Essentiality /15
14.0
Special reductions
−3.8

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 How the historical reference is calculated.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
6/9
Fair (5–6)
Superstructure
5/9
Fair (5–6)
Substructure
6/9
Fair (5–6)
Inventory Load Rating
23.6 t
NBI inventory level (metric tons)
Overall Condition
Fair

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

Structural Details

Year Built
1968
Material
Steel Continuous
Number of Spans
4
Structure Length
322.1 m (1057 ft)
Deck Width
10.1 m (33 ft)
Owner
State Highway Agency
Avg Daily Traffic
134 vehicles/day
Structure Number
S00480003+00001

Condition Analysis

  • At 6/9, the deck (driving surface) shows fair condition, with minor wear flagged for upkeep.
  • The superstructure (beams and supports above the deck) is in fair condition (5/9), with minor deterioration that may require routine maintenance.
  • The substructure (piers and abutments) is in fair condition (6/9), with minor deterioration that may require routine maintenance.

How to read this record

This page shows what the last federal inspection recorded, not whether IRR - SR 480 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 IRR - SR 480 against other structures in Richland and across Montana. Montana 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 IRR - SR 480?

IRR - SR 480 in Richland, Montana has a deck rating of 6/9, superstructure rating of 5/9, and substructure rating of 6/9 on the FHWA's 0–9 scale.

How often is IRR - SR 480 inspected?

IRR - SR 480'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 134 vehicles per day.

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

FHWA retired that reported status beginning with the 2018 archive. IRR - SR 480 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 IRR - SR 480?

IRR - SR 480 has an NBI inventory load rating of 23.6 metric tons.

Who is responsible for maintaining IRR - SR 480?

IRR - SR 480 is owned and maintained by State Highway Agency.

How old is IRR - SR 480 and does age affect safety?

IRR - SR 480 was built in 1968, making it 58 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.