STH 121
Carrying STH 121 over THREE MILE CREEK
2.5M E JCT STH 88, Buffalo, Wisconsin
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
STH 121 in Buffalo, Wisconsin sits above 32% of rated Wisconsin bridges on inventory load rating (32 t), while its 1986 build year is earlier than 59% of Buffalo's recorded-year cohort (238 bridges).
STH 121 in Buffalo, Wisconsin is rated Fair in the FHWA's 2024 National Bridge Inventory. Built in 1986, it carries 1 rated component 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 WI:B06005100000000
LATE-CENTURY · CONCRETE · MULTI-SPAN · CULVERT-LED · LOCAL-ADT · STANDARD-LOAD · CAT-FAIR
- LATE-CENTURY 1980–1999
- CONCRETE Concrete
- MULTI-SPAN 2 spans
- CULVERT-LED Culvert-led
- LOCAL-ADT Local 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: STH 121
The STH 121 bridge in Buffalo, Wisconsin carries STH 121 over THREE MILE CREEK. It was built in 1986, making it 40 years old today. The structure is built primarily of concrete and spans 2 sections, stretching 7.0 meters (23 feet) end to end. Daily traffic averages 540 vehicles, placing it in the lower-traffic tier of Wisconsin bridges. It is owned and maintained by State Highway Agency.
The latest FHWA inspection records show culvert at 6/9. The weakest component sits in fair condition. No reported major component scores in the Poor range under the current federal condition thresholds.
How STH 121 compares
Age against the county: built in 1986, earlier than 141 of Buffalo's 238 bridges with a recorded construction year (59%), against a county median build year of 1991. Age is not a defect on its own, but it is the population from which future Poor ratings are drawn.
Live comparison across Wisconsin bridges with a recorded inventory load rating (14,446 rated).
STH 121 vs every rated Wisconsin bridge
Inventory load rating (metric tons), FHWA NBI, this state
32 Top 68% higher than 32% of 14,446 bridges
rated Wisconsin 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.
Buffalo inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 238 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
- 1986
- Material
- Concrete
- Number of Spans
- 2
- Structure Length
- 7.0 m (23 ft) 0
- Owner
- State Highway Agency
- Avg Daily Traffic
- 540 vehicles/day
- Structure Number
- B06005100000000
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 STH 121 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 STH 121 against other structures in Buffalo and across Wisconsin. Wisconsin 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 STH 121?
STH 121 in Buffalo, Wisconsin on the FHWA's 0–9 scale.
How often is STH 121 inspected?
STH 121'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 540 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. STH 121 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 STH 121?
STH 121 has an NBI inventory load rating of 32.4 metric tons.
Who is responsible for maintaining STH 121?
STH 121 is owned and maintained by State Highway Agency.
How old is STH 121 and does age affect safety?
STH 121 was built in 1986, making it 40 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.