FHWA NBI 2024 Inspection record Public-domain dataset

IRR SD063

Carrying IRR SD063 over RUDY CK TRIBUTARY

9.4 S DEWEY CO LINE, Ziebach, South Dakota

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Good
100 t Inventory load rating

Bridge Snapshot: IRR SD063

The IRR SD063 bridge in Ziebach, South Dakota carries IRR SD063 over RUDY CK TRIBUTARY. It was built in 1994, making it 32 years old today. The structure is built primarily of concrete continuous and spans 2 sections, stretching 6.3 meters (21 feet) end to end. Daily traffic averages 656 vehicles, placing it in the lower-traffic tier of South Dakota bridges. It is owned and maintained by State Highway Agency.

The latest FHWA inspection records show culvert at 7/9. The weakest component sits in good condition. No reported major component scores in the Poor range under the current federal condition thresholds. Its NBI inventory load rating is 99.9 metric tons.

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

How IRR SD063 compares

▲ 67.4
Load rating vs South Dakota average (32.5 t)
Top 3%
Higher load rating than 97% of South Dakota bridges
30
Bridges in Ziebach · 3 in Poor condition
IRR SD063 99.9 t
South Dakota average 32.5 t

Live comparison across South Dakota.

Historical Sufficiency Rating

PlainBridge-computed
94.6 / 100 - historical 80–100 band
Structural adequacy /55
55.0
Serviceability /30
30.0
Essentiality /15
11.3
Special reductions
−1.7

FHWA discontinued this calculated item; it does not determine current condition, funding eligibility, posting, or closure. How the historical reference is calculated.

Condition Ratings

Culvert
7/9
Good (7–9)
Inventory Load Rating
99.9 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 Continuous
Number of Spans
2
Structure Length
6.3 m (21 ft)
Owner
State Highway Agency
Avg Daily Traffic
656 vehicles/day
Structure Number
000000069360425

How to read this record

This page shows what the last federal inspection recorded, not whether IRR SD063 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 SD063 against other structures in Ziebach and across South Dakota. South Dakota 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 SD063?

IRR SD063 in Ziebach, South Dakota on the FHWA's 0–9 scale.

How often is IRR SD063 inspected?

IRR SD063'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 656 vehicles per day.

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

FHWA retired that reported status beginning with the 2018 archive. IRR SD063 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 IRR SD063?

IRR SD063 has an NBI inventory load rating of 99.9 metric tons.

Who is responsible for maintaining IRR SD063?

IRR SD063 is owned and maintained by State Highway Agency.

How old is IRR SD063 and does age affect safety?

IRR SD063 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.