FHWA NBI 2024 Inspection record Public-domain dataset

478TH AVENUE

Carrying 478TH AVENUE over MEDARY CK

2E & 0.1N AURORA, Brookings, South Dakota

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Fair
20 t Inventory load rating

Bridge Snapshot: 478TH AVENUE

The 478TH AVENUE bridge in Brookings, South Dakota carries 478TH AVENUE over MEDARY CK. It was built in 1981, making it 45 years old today. The structure is built primarily of prestressed concrete and spans 2 sections, stretching 30.8 meters (101 feet) end to end. Daily traffic averages 92 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 7/9, superstructure at 7/9, substructure at 6/9. The weakest component sits in fair condition. None of this bridge's reported major components fall into the Poor condition range. Its NBI inventory load rating is 19.6 metric tons.

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

How 478TH AVENUE compares

▼ 12.9
Load rating vs South Dakota average (32.5 t)
Bottom 20%
Lower load rating than 80% of South Dakota bridges
234
Bridges in Brookings · 53 in Poor condition
478TH AVENUE 19.6 t
South Dakota average 32.5 t

Live comparison across South Dakota.

Historical Sufficiency Rating

PlainBridge-computed
82.1 / 100 - historical 80–100 band
Structural adequacy /55
40.1
Serviceability /30
29.0
Essentiality /15
15.0
Special reductions
−2.0

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 How the historical reference is calculated.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
7/9
Good (7–9)
Superstructure
7/9
Good (7–9)
Substructure
6/9
Fair (5–6)
Inventory Load Rating
19.6 t
NBI inventory level (metric tons)
Overall Condition
Fair

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

Structural Details

Year Built
1981
Material
Prestressed Concrete
Number of Spans
2
Structure Length
30.8 m (101 ft)
Deck Width
8.2 m (27 ft)
Owner
County Highway Agency
Avg Daily Traffic
92 vehicles/day
Structure Number
000000006240179

Condition Analysis

  • At 7/9, the deck (driving surface) is in good shape and shows no significant wear.
  • At 7/9, the superstructure (beams and supports above the deck) is in good shape and shows no significant wear.
  • 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 478TH AVENUE 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 478TH AVENUE against other structures in Brookings 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 478TH AVENUE?

478TH AVENUE in Brookings, South Dakota has a deck rating of 7/9, superstructure rating of 7/9, and substructure rating of 6/9 on the FHWA's 0–9 scale.

How often is 478TH AVENUE inspected?

478TH 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 92 vehicles per day.

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

FHWA retired that reported status beginning with the 2018 archive. 478TH AVENUE 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 478TH AVENUE?

478TH AVENUE has an NBI inventory load rating of 19.6 metric tons.

Who is responsible for maintaining 478TH AVENUE?

478TH AVENUE is owned and maintained by County Highway Agency.

How old is 478TH AVENUE and does age affect safety?

478TH AVENUE was built in 1981, making it 45 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.