County profile · official public datasets

Pinal County, AZ

716 public highway bridges tracked in the FHWA National Bridge Inventory: 63.5% rated Good, 35.5% Fair, 1% Poor.

716
Public bridges: 63.5%
Good condition: 1%
Poor condition

The verdict

According to the Federal Highway Administration's 2024 National Bridge Inventory.

Pinal County posts a better-than-median Poor-condition share among rated counties in the state across large county bridge inventory.

Top 33%
lowest Poor share in state: 1%
Poor-condition share: 716
public highway bridges: 1973
avg year built

Poor is an FHWA condition category from the lowest applicable component rating (4 or below), not a live crossing-safety or closure decision. Rankings cover counties with at least five public highway bridges.

Pinal County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Pinal County ranks #5 of 15 Arizona counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 1%). Pinal County, Arizona contains 716 public highway bridges. Roughly 63.5% are rated “Good,” 35.5% “Fair,” and 1% “Poor.” Poor means the lowest applicable deck, superstructure, substructure, or culvert rating is 4 or below on the 0–9 NBI scale. It is a condition category, not a live safety or closure decision.

Responsible agencies inspect covered bridges on risk-based intervals under current NBIS rules and submit inventory data to FHWA annually. The list below shows every NBI-tracked bridge in the county. Use the “Sort by” controls to change the ordering, and click any row for its reported inspection date, traffic count, and condition fields.

Source: FHWA National Bridge Inventory. See methodology for full definitions.

Total bridges

716

Public highway bridges in Pinal County

Good condition

63.5%

455 of 716 rated 7-9

Fair condition

35.5%

254 of 716 rated 5-6

Poor condition

7 of 716 rated 4 or below

In-state Poor-share rank

#5 of 15

Among Arizona counties with 5+ bridges, lower share ranks better

Condition distribution

Share of 716 NBI-tracked bridges by lowest applicable component rating.

Good

63.5% (455)

Fair

35.5% (254)

Poor

1% (7)

Pinal County's Poor-condition bridges carry 16,712 vehicle crossings a day

That is 0.3% of the county's reported daily bridge traffic on 1% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 2,387 crossings a day against 8,660 for a Good-condition one. A Poor rating is a condition category, not a closure or a live safety judgement; it means the lowest applicable component rating is 4 or below.

Computed over the 716 of 716 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

61.9% of Pinal County's bridges have passed the 50-year mark

443 of the 716 bridges with a recorded construction year were built in 1974 or earlier. Age alone is not a defect: a well-maintained older bridge can rate Good, and 63.5% of this county's inventory does. Even so, this older cohort is the population from which future Poor ratings are drawn, which is why the age profile below matters alongside the condition split above.

Cutoff derives from the 2024 release year minus a 50-year design life. Source: FHWA National Bridge Inventory, 2024 release.

One structure carries 45.2% of the county's Poor-condition bridge traffic

US 60 over Waterfall Canyon, built 1929, carries 7,553 vehicles a day, the most of any Poor-rated structure here. The county's Poor-condition exposure is concentrated rather than evenly spread, so the 7-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 16,712 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1900s

2
1910s

1
1920s

15
1930s

43
1940s

44
1950s

83
1960s

231
1970s

31
1980s

54
1990s

71
2000s

87
2010s

49
2020s

5

What this shows Construction peaked in the 1960s, when 231 of the county's bridges still in the inventory were built, which is 32.3% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year (1973) matches the Arizona average (1977).

How Pinal County compares with Arizona's closest counties by inventory size

The 5 Arizona counties nearest Pinal County in number of bridges, with their condition splits. Its 1% Poor share is the 3rd-lowest of these 6. Its average build year of 1973 against a peer-group mean of 1966 is 7 years newer.

Showing the 5 closest of 14 Arizona counties eligible for comparison.

Bridge inventory size and condition shares for Pinal County and the 5 Arizona counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Pinal County (this page)	716	63.5%	35.5%	1%	1973
Mohave County	641	71.6%	27.8%	0.6%	1976
Yavapai County	543	63.2%	36.3%	0.6%	1970
Cochise County	501	55.3%	42.5%	2.2%	1956
Coconino County	405	51.9%	46.9%	1.2%	1969
La Paz County	306	64.1%	32.4%	3.6%	1961

Each share is of that county's own total tracked bridges; peers are the counties with 5 or more bridges whose inventory size is closest to Pinal County's. Source: FHWA National Bridge Inventory, 2024 release.

Nationwide counties with similar inventory size or average build year

Two NBI-derived peer sets for Pinal County, both outside Arizona so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside AZ (716 bridges here).

McLennan County, TX · 714 bridges
Pulaski County, AR · 721 bridges
Madison County, AL · 710 bridges
Montgomery County, TX · 710 bridges

Similar average build year

Nearest mean year-built outside AZ (1973 here).

Jefferson County, AL · avg 1973 · 1,068 bridges
Erie County, NY · avg 1973 · 906 bridges
Davidson County, TN · avg 1973 · 832 bridges
Lancaster County, PA · avg 1973 · 801 bridges

Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.

All 716 Good 455 Fair 254 Poor 7

Good-condition bridges (455)

Sort:

Pinal County Bridge Snapshot

Condition distribution

Pinal County's Poor-condition bridges carry 16,712 vehicle crossings a day

61.9% of Pinal County's bridges have passed the 50-year mark

One structure carries 45.2% of the county's Poor-condition bridge traffic

How Pinal County compares with Arizona's closest counties by inventory size

Nationwide counties with similar inventory size or average build year

Similar inventory size

Similar average build year

Good-condition bridges (455)

San Man-Tiger Hwy

SR79

US 60

SR 77

SR 77

SR 77

SR 77

SR 77

SR 177

SR 177

SR 177

I 8; EB

I 8; WB

I 8; EB

I 8; WB

I 8; EB

I 8; WB

I 8; EB

I 8; EB

I 8; WB

I 8

SR 177

SR 77

SR 77

IRR I 10

IRR McCartney Rd

I 10 Ramp B

IRR; SR 347

IRR; SR 347

IRR; SR 347

IRR Maricopa Rd

US 60

US 60

US 60

US 60

US 60

San Man-Tiger Hwy

San Man-Tiger Hwy

Oro Viejo Drive

Mountainbrook Dr

Missile Base Road

Park Link Dr

Grand Valley Road

Porter Road

Ironwood Drive

Ironwood Drive

Ironwood Drive

Ironwood Drive

Schnepf Road

S Pinnacle Dr

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