464th Avenue
Carrying 464th Avenue over Creek
3W & 1.9N of Wilmot, Roberts, South Dakota
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
464th Avenue in Roberts, South Dakota sits above 6% of rated South Dakota bridges on inventory load rating (11 t), while its 1950 build year is earlier than 69% of Roberts's recorded-year cohort (157 bridges).
464th Avenue in Roberts, South Dakota is rated Poor in the FHWA's 2024 National Bridge Inventory. Built in 1950, it carries 3 rated components on the inspecting agency's 0-9 scale, and its weakest reported component scores 4. The lowest applicable rating sets the federal condition category, so this Poor result describes the weakest reported component rather than the structure as a whole. No NBI category is a closure decision or a live crossing-safety verdict.
NBI record plate
Structure SD:000000055150341
INTERSTATE-ERA · TIMBER · MULTI-SPAN · TIED-CTRL · TRACE-ADT · LIGHT-LOAD · CAT-POOR
- INTERSTATE-ERA 1950–1979
- TIMBER Wood or timber
- MULTI-SPAN 2 spans
- TIED-CTRL Tied control
- TRACE-ADT Trace ADT
- LIGHT-LOAD Light load
- CAT-POOR Poor
Inspection-sheet codes from this record’s year, material family, spans, controlling component, ADT, inventory load, and NBI category, not a live closure verdict.
Bridge Snapshot: 464th Avenue
The 464th Avenue bridge in Roberts, South Dakota carries 464th Avenue over Creek. It was built in 1950, making it 76 years old today. The structure is built primarily of wood or timber and spans 2 sections, stretching 7.5 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 4/9, substructure at 4/9. The weakest component sits in poor condition. A component scored 4 or below, placing this bridge in the federal Poor condition category rather than declaring it unsafe or closed.
How 464th Avenue compares
Age against the county: built in 1950, earlier than 109 of Roberts's 157 bridges with a recorded construction year (69%), against a county median build year of 1976. Age is not a defect on its own, but it is the population from which future Poor ratings are drawn.
Live comparison across South Dakota bridges with a recorded inventory load rating (5,886 of 5,887 rated).
464th Avenue vs every rated South Dakota bridge
Inventory load rating (metric tons), FHWA NBI, this state
11 Top 94% higher than 6% of 5,886 bridges
rated South Dakota bridges, bucketed by value
Each bar is a band; taller bars hold more bridges. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source FHWA National Bridge Inventory · August 2026
Condition Ratings
Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.
Reported 0–9 component ratings from the FHWA NBI. The highlighted component is the lowest reported input to this record’s current condition category; it is not a closure or live crossing-safety decision.
Roberts inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 157 bridges in this county. Orthogonal to this structure's component profile above: a county catalog share, not a live crossing-safety verdict.
Structural Details
- Year Built
- 1950
- Material
- Wood or Timber
- Number of Spans
- 2
- Structure Length
- 7.5 m (25 ft)
- Deck Width
- 7.3 m (24 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 20 vehicles/day
- Structure Number
- 000000055150341
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) rates poor at 4/9, with advanced deterioration recorded on the latest inspection.
- • At 4/9, the substructure (piers and abutments) is in poor shape, with advanced wear on file for this vintage.
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗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 4/9, 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 11.0 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 1950, making it 76 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.
Share this inspection record
Send this source-bounded record or download its data card. An NBI condition category is not a closure or live crossing-safety verdict.
Every figure on PlainBridges is rendered directly from federal source data, no number is typed in by an editor. Component ratings, ADT, and condition category on this page are copied from the NBI record for this structure; no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 2024 NBI release. NBI condition categories reflect the latest reported inventory record, not a live safety, closure, or travel decision.