FHWA NBI 2024 Inspection record Public-domain dataset

324 AVENUE

Carrying 324 AVENUE over MOCASSIN CK

0.3N & 0.2E OF HAMILL, Tripp, South Dakota

Data updated May 2026

FHWA NBI record, refreshed with each annual release.

Poor
7 t Inventory load rating

Bridge Snapshot: 324 AVENUE

The 324 AVENUE bridge in Tripp, South Dakota carries 324 AVENUE over MOCASSIN CK. It was built in 1924, making it 102 years old today. The structure is built primarily of steel and spans 2 sections, stretching 18.4 meters (60 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 4/9, superstructure at 5/9, substructure at 5/9. 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. Its NBI inventory load rating is 7.4 metric tons.

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

How 324 AVENUE compares

▼ 25.1
Load rating vs South Dakota average (32.5 t)
Bottom 3%
Lower load rating than 97% of South Dakota bridges
90
Bridges in Tripp · 25 in Poor condition
324 AVENUE 7.4 t
South Dakota average 32.5 t

Live comparison across South Dakota.

Historical Sufficiency Rating

PlainBridge-computed
36.3 / 100 - historical 20–49.9 band
Structural adequacy /55
4.3
Serviceability /30
17.0
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 How the historical reference is calculated.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
4/9
Poor (1–4)
Superstructure
5/9
Fair (5–6)
Substructure
5/9
Fair (5–6)
Inventory Load Rating
7.4 t
NBI inventory level (metric tons)
Overall Condition
Poor

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

Structural Details

Year Built
1924
Material
Steel
Number of Spans
2
Structure Length
18.4 m (60 ft)
Deck Width
6.1 m (20 ft)
Owner
County Highway Agency
Avg Daily Traffic
20 vehicles/day
Structure Number
000000062283121

Condition Analysis

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

How to read this record

324 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 324 AVENUE against other structures in Tripp 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 324 AVENUE?

324 AVENUE in Tripp, South Dakota has a deck rating of 4/9, superstructure rating of 5/9, and substructure rating of 5/9 on the FHWA's 0–9 scale.

How often is 324 AVENUE inspected?

324 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. 324 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 324 AVENUE?

324 AVENUE has an NBI inventory load rating of 7.4 metric tons.

Who is responsible for maintaining 324 AVENUE?

324 AVENUE is owned and maintained by County Highway Agency.

How old is 324 AVENUE and does age affect safety?

324 AVENUE was built in 1924, making it 102 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.