FHWA NBI 2024 Inspection record Public-domain dataset

464th Avenue

Carrying 464th Avenue over N. Fork Whetstone Rv

3W & 3.5N of Wilmot, Roberts, South Dakota

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Poor
12 t Inventory load rating

Bridge Snapshot: 464th Avenue

The 464th Avenue bridge in Roberts, South Dakota carries 464th Avenue over N. Fork Whetstone Rv. It was built in 1929, making it 97 years old today. The structure is built primarily of wood or timber and spans 2 sections, stretching 7.6 meters (25 feet) end to end. Daily traffic averages 20 vehicles, placing it in the lower-traffic tier of South Dakota bridges. It is owned and maintained by County Highway Agency.

The latest FHWA inspection records show a deck rating of 5/9, superstructure at 5/9, substructure at 4/9. 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 12.2 metric tons.

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

How 464th Avenue compares

▼ 20.3
Load rating vs South Dakota average (32.5 t)
Bottom 7%
Lower load rating than 93% of South Dakota bridges
157
Bridges in Roberts · 38 in Poor condition
464th Avenue 12.2 t
South Dakota average 32.5 t

Live comparison across South Dakota.

Historical Sufficiency Rating

PlainBridge-computed
39.4 / 100 - historical 20–49.9 band
Structural adequacy /55
0.5
Serviceability /30
24.0
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 How the historical reference is calculated.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
5/9
Fair (5–6)
Superstructure
5/9
Fair (5–6)
Substructure
4/9
Poor (1–4)
Inventory Load Rating
12.2 t
NBI inventory level (metric tons)
Overall Condition
Poor

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

Structural Details

Year Built
1929
Material
Wood or Timber
Number of Spans
2
Structure Length
7.6 m (25 ft)
Deck Width
7.3 m (24 ft)
Owner
County Highway Agency
Avg Daily Traffic
20 vehicles/day
Structure Number
000000055150325

Condition Analysis

  • The deck (driving surface) rates fair at 5/9, minor deterioration that routine maintenance should address.
  • The superstructure (beams and supports above the deck) is in fair condition (5/9), with minor deterioration that may require routine maintenance.
  • At 4/9, the substructure (piers and abutments) is in poor shape, with advanced wear flagged for priority repair.

How to read this record

464th Avenue 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 464th Avenue against other structures in Roberts 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 464th Avenue?

464th Avenue in Roberts, South Dakota has a deck rating of 5/9, superstructure rating of 5/9, and substructure rating of 4/9 on the FHWA's 0–9 scale.

How often is 464th Avenue inspected?

464th Avenue'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 20 vehicles per day.

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

FHWA retired that reported status beginning with the 2018 archive. 464th Avenue 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 464th Avenue?

464th Avenue has an NBI inventory load rating of 12.2 metric tons.

Who is responsible for maintaining 464th Avenue?

464th Avenue is owned and maintained by County Highway Agency.

How old is 464th Avenue and does age affect safety?

464th Avenue was built in 1929, making it 97 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.