US 60

over Queen Creek

0.5 mi E Jct SR 177, Pinal County, Arizona

Condition

Poor

Year Built

1949

Daily Traffic

6,929

Length

58 ft

About This Bridge

US 60 carries traffic over Queen Creek in Pinal County, Arizona. Built in 1949, this structure is 77 years old, making it a historic structure that has served the community for generations. The bridge features steel construction with a arch - deck design, a combination chosen by engineers to meet the specific requirements of this crossing.

Approximately 6,929 vehicles cross this bridge daily, indicating lower traffic volumes common for local roads and rural routes. While traffic is lighter, these bridges still serve essential community transportation needs. Commercial trucks account for 10% of all crossings. This proportion of commercial traffic is typical for this roadway classification and is factored into the bridge's design load ratings.

The bridge is currently rated in poor condition based on federal inspection criteria established by the Federal Highway Administration. It is classified as structurally deficient, meaning one or more components have received a rating of 4 or below on the 0-9 scale. This designation indicates significant deterioration that warrants attention, though the bridge remains safe for travel within its posted limits. Structurally deficient does not mean unsafe—rather, it signals that repairs or replacement should be prioritized in transportation planning. With a total length of 58 feet, this is a shorter span typical of local road crossings, often carrying traffic over small streams, drainage channels, or other roadways.

Steel bridges provide high strength-to-weight ratios, making them suitable for longer spans. However, they require ongoing protection against corrosion through painting or weathering steel designs. Inspectors pay close attention to connection points, fatigue cracking, and coating condition.

Federal law requires that all highway bridges be inspected at least every 24 months by qualified inspectors following the National Bridge Inspection Standards (NBIS). Some bridges with known issues or unusual characteristics may be inspected more frequently. Inspection data is reported to the National Bridge Inventory, a database maintained by the Federal Highway Administration that tracks the condition of all public highway bridges in the United States. This bridge data is sourced from that federal database and reflects the most recent available inspection results.

Condition Ratings

Structurally Deficient

This bridge has one or more component ratings of 4 or below, indicating significant deterioration that requires attention. The bridge remains safe for travel but may have load restrictions.

4

Deck Condition

Poor

4

Superstructure

Poor

4

Substructure

Poor

8

Channel & Protection

Very Good

4

Lowest Rating

Determines condition category

NBI condition ratings range from 0 (failed) to 9 (excellent). Ratings of 4 or below are considered poor. The overall condition category is determined by the lowest individual component rating.

The deck rating of 4 indicates advanced deterioration affecting the driving surface. The superstructure rating of 4 shows advanced deterioration in beams or girders. The substructure rating of 4 reflects significant wear in piers, abutments, or foundations.

For a structure built in 1949, the current condition reflects the cumulative effects of age, traffic, and environmental exposure. If this bridge were closed, traffic would face a detour of approximately 68 miles, underscoring the importance of maintaining this crossing.

Bridge Details

Steel is the primary structural material, which influences maintenance requirements and expected lifespan. The arch - deck design was selected based on span requirements, load capacity needs, and site conditions at the time of construction. Maintenance responsibility falls to State Highway Agency.

Construction

Year Built1949
MaterialSteel
Design TypeArch - Deck
OwnerState Highway Agency

Dimensions

Total Length58 ft (17.6 m)
Max Span38 ft (11.6 m)
Deck Width3 ft
Deck Area1,829 sq ft

Span dimensions affect structural design choices and load distribution. The deck area of 1,829 sq ft determines surface maintenance scope.

Classification

Route TypeUS Highway
Route Number6
Lanes On Bridge2
Lanes Under Bridge

Status

Toll BridgeNo
Historical SignificancePossibly eligible
Scour Critical8
Detour Length68 mi (109 km)

Traffic Data

Traffic volume data helps engineers assess bridge wear patterns and plan maintenance schedules. Average Daily Traffic (ADT) counts are updated periodically and represent typical weekday usage.

6,929

Avg Daily Traffic (2021)

Vehicles per day crossing this bridge

10%

Truck Traffic

Commercial vehicle percentage

6,939

Projected Future ADT

Estimated future demand

This bridge carries approximately 6,929 vehicles per day, translating to roughly 2,529,085 crossings annually. Lower traffic volumes generally result in less structural wear over time.

Commercial trucks comprise 10% of traffic. Heavy vehicles cause disproportionate wear—a single fully loaded truck can have the impact of thousands of passenger cars on bridge deck surfaces.

Traffic projections estimate future volumes of 6,939 vehicles daily, a 0% increase from current levels. These projections inform capacity planning and potential upgrade requirements.

Load Ratings

Load ratings determine what weight this bridge can safely support. These values are critical for routing heavy vehicles and issuing overweight permits.

Operating Rating

5.2 tons

Maximum allowable load for special permits

Inventory Rating

3.1 tons

Load level for normal traffic

The operating rating of 5.2 tons represents the absolute maximum load this bridge can carry under controlled conditions with special permits. The inventory rating of 3.1 tons is the safe load limit for everyday traffic without restrictions. These relatively low ratings may result in posted weight limits or route restrictions for heavy vehicles.

5-Year Condition Trend

Stable

Condition has remained relatively stable since 2020

Data: 2020-2024 FHWA National Bridge Inventory

Location

Loading map...

34.770000, -111.700000

Identification

Structure Number00406
NBI IDAZ-00406
State FIPS04
County FIPS021

Explore More

Data Source: Federal Highway Administration (FHWA) National Bridge Inventory 2024

Bridge inspection data is typically updated every 24 months. Conditions may have changed since the last inspection.

“Structurally deficient” does not mean a bridge is unsafe or likely to collapse. It indicates that one or more key structural elements are in poor or worse condition. Bridges are inspected regularly and may have load restrictions in place.

This data is for informational purposes only and should not be used for route clearance or vehicle weight decisions.

US 60 over Queen Creek | Arizona