121ST AVE
Carrying 121ST AVE over GREEN RIVER
8 EAST 12 SOUTH FAIRFIELD, Billings, North Dakota
Data updated May 2026
FHWA NBI record, refreshed with each annual release.
Bridge Snapshot: 121ST AVE
The 121ST AVE bridge in Billings, North Dakota carries 121ST AVE over GREEN RIVER. It was built in 1946, making it 80 years old today. It was last reconstructed in 1975, extending its service life. The structure is built primarily of prestressed concrete and spans 1 section, stretching 15.2 meters (50 feet) end to end. Daily traffic averages 26 vehicles, placing it in the lower-traffic tier of North 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. All reported major components score above the Poor range. Its NBI inventory load rating is 19.1 metric tons.
Sourced from the FHWA National Bridge Inventory. See our methodology for refresh cadence and NBI release vintage.
How 121ST AVE compares
Live comparison across North Dakota.
Historical Sufficiency Rating
PlainBridge-computedFHWA discontinued this calculated item; it does not determine current condition, funding eligibility, posting, or closure. How the historical reference is calculated.
Condition Ratings
Full 0–9 scale + sufficiency-rating breakdown: how condition ratings work.
Structural Details
- Year Built
- 1946
- Last Reconstructed
- 1975
- Material
- Prestressed Concrete
- Number of Spans
- 1
- Structure Length
- 15.2 m (50 ft)
- Deck Width
- 9.3 m (31 ft)
- Owner
- County Highway Agency
- Avg Daily Traffic
- 26 vehicles/day
- Structure Number
- 000000004129210
Location
Data Source
FHWA National Bridge Inventory (NBI).
FHWA NBI Program ↗Condition Analysis
- • The deck (driving surface) is in good condition (7/9), showing no significant deterioration.
- • 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 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 121ST AVE 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 121ST AVE against other structures in Billings and across North Dakota. North 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 121ST AVE?
121ST AVE in Billings, North 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 121ST AVE inspected?
121ST AVE'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 26 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. 121ST AVE 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 121ST AVE?
121ST AVE has an NBI inventory load rating of 19.1 metric tons.
Who is responsible for maintaining 121ST AVE?
121ST AVE is owned and maintained by County Highway Agency.
How old is 121ST AVE and does age affect safety?
121ST AVE was built in 1946, making it 80 years old and last reconstructed in 1975.
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.
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.