51st Avenue
Carrying 51st Avenue over Skunk Creek
0.50 mi N of Union Hills, Maricopa, Arizona
Inventory: FHWA NBI 2024 · last ETL August 2026
FHWA NBI record, refreshed with each annual release.
51st Avenue in Maricopa, Arizona sits above 13% of rated Arizona bridges on inventory load rating (30 t), while its 1991 build year is earlier than 50% of Maricopa's recorded-year cohort (2,847 bridges).
51st Avenue in Maricopa, Arizona is rated Good in the FHWA's 2024 National Bridge Inventory. Built in 1991, it carries 3 rated components on the inspecting agency's 0-9 scale, and its weakest reported component scores 7. The lowest applicable rating sets the federal condition category, so this Good 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 AZ:07921
LATE-CENTURY · PRESTRESS · MULTI-SPAN · TIED-CTRL · HEAVY-ADT · STANDARD-LOAD · CAT-GOOD
- LATE-CENTURY 1980–1999
- PRESTRESS Prestressed concrete
- MULTI-SPAN 2 spans
- TIED-CTRL Tied control
- HEAVY-ADT Heavy ADT
- STANDARD-LOAD Standard load
- CAT-GOOD Good
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: 51st Avenue
The 51st Avenue bridge in Maricopa, Arizona carries 51st Avenue over Skunk Creek. It was built in 1991, making it 35 years old today. The structure is built primarily of prestressed concrete continuous and spans 2 sections, stretching 47.2 meters (155 feet) end to end. Daily traffic averages 22,729 vehicles, placing it in the heavily-trafficked tier of Arizona bridges. It is owned and maintained by City/Municipal Highway Agency.
The latest FHWA inspection records show a deck rating of 7/9, superstructure at 8/9, substructure at 7/9. The weakest component sits in good condition. No reported major component scores in the Poor range under the current federal condition thresholds.
How 51st Avenue compares
Age against the county: built in 1991, earlier than 1,414 of Maricopa's 2,847 bridges with a recorded construction year (50%), against a county median build year of 1991.
Live comparison across Arizona bridges with a recorded inventory load rating (8,572 of 8,573 rated).
51st Avenue vs every rated Arizona bridge
Inventory load rating (metric tons), FHWA NBI, this state
30 Top 87% higher than 13% of 8,572 bridges
rated Arizona 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.
Maricopa inventory by recorded NBI category
Exclusive Good/Fair/Poor bands across all 2,847 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
- 1991
- Material
- Prestressed Concrete Continuous
- Number of Spans
- 2
- Structure Length
- 47.2 m (155 ft)
- Deck Width
- 28.9 m (95 ft)
- Owner
- City/Municipal Highway Agency
- Avg Daily Traffic
- 22,729 vehicles/day
- Structure Number
- 07921
Condition Analysis
- • The deck (driving surface) rates good at 7/9, with no significant deterioration on file.
- • The superstructure (beams and supports above the deck) rates good at 8/9, 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 51st 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 51st Avenue against other structures in Maricopa and across Arizona. Arizona 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 51st Avenue?
51st Avenue in Maricopa, Arizona has a deck rating of 7/9, superstructure rating of 8/9, and substructure rating of 7/9 on the FHWA's 0–9 scale.
How often is 51st Avenue inspected?
51st 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 22,729 vehicles per day.
What does “structurally deficient” mean in older bridge reports?
FHWA retired that reported status beginning with the 2018 archive. 51st Avenue is currently shown as Good condition from its component ratings; that category is not a live closure or safety decision.
What is the inventory load rating for 51st Avenue?
51st Avenue has an NBI inventory load rating of 30.4 metric tons.
Who is responsible for maintaining 51st Avenue?
51st Avenue is owned and maintained by City/Municipal Highway Agency.
How old is 51st Avenue and does age affect safety?
51st Avenue was built in 1991, making it 35 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.