46120 315 ST.
Carrying 46120 315 ST. over CLAY CK DITCH
2.5N & 2.9W VERMILLION, Clay, South Dakota
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
46120 315 ST. in Clay, South Dakota sits above 66% of rated South Dakota bridges on inventory load rating (34 t), while its 1988 build year is earlier than 56% of Clay's recorded-year cohort (94 bridges).
46120 315 ST. in Clay, South Dakota is rated Fair in the FHWA's 2024 National Bridge Inventory. Built in 1988, it carries 3 rated components on the inspecting agency's 0-9 scale, and its weakest reported component scores 6. The lowest applicable rating sets the federal condition category, so this Fair 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:000000014092180
LATE-CENTURY · CONCRETE · MULTI-SPAN · DECK-LED · TRACE-ADT · STANDARD-LOAD · CAT-FAIR
- LATE-CENTURY 1980–1999
- CONCRETE Concrete
- MULTI-SPAN 3 spans
- DECK-LED Deck-led
- TRACE-ADT Trace ADT
- STANDARD-LOAD Standard load
- CAT-FAIR Fair
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: 46120 315 ST.
The 46120 315 ST. bridge in Clay, South Dakota carries 46120 315 ST. over CLAY CK DITCH. It was built in 1988, making it 38 years old today. The structure is built primarily of concrete continuous and spans 3 sections, stretching 24.4 meters (80 feet) end to end. Daily traffic averages 35 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 6/9, superstructure at 7/9, substructure at 7/9. The weakest component sits in fair condition. All reported major components score above the Poor range.
How 46120 315 ST. compares
Age against the county: built in 1988, earlier than 53 of Clay's 94 bridges with a recorded construction year (56%), against a county median build year of 1996. 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).
46120 315 ST. vs every rated South Dakota bridge
Inventory load rating (metric tons), FHWA NBI, this state
34 Top 34% higher than 66% 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.
Clay inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 94 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
- 1988
- Material
- Concrete Continuous
- Number of Spans
- 3
- Structure Length
- 24.4 m (80 ft)
- Deck Width
- 9.2 m (30 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 35 vehicles/day
- Structure Number
- 000000014092180
Condition Analysis
- • The deck (driving surface) is in fair condition (6/9), with minor deterioration that may require routine maintenance.
- • The superstructure (beams and supports above the deck) rates good at 7/9, with no significant deterioration on file.
- • The substructure (piers and abutments) is in good condition (7/9), showing no significant deterioration.
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗How to read this record
This page shows what the last federal inspection recorded, not whether 46120 315 ST. 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 46120 315 ST. against other structures in Clay 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 46120 315 ST.?
46120 315 ST. in Clay, South Dakota has a deck rating of 6/9, superstructure rating of 7/9, and substructure rating of 7/9 on the FHWA's 0–9 scale.
How often is 46120 315 ST. inspected?
46120 315 ST.'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 35 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. 46120 315 ST. 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 46120 315 ST.?
46120 315 ST. has an NBI inventory load rating of 34.3 metric tons.
Who is responsible for maintaining 46120 315 ST.?
46120 315 ST. is owned and maintained by County Highway Agency.
How old is 46120 315 ST. and does age affect safety?
46120 315 ST. was built in 1988, making it 38 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.