US Bridges

IRR US 70 over Patterson Wash

Fair

Graham County, Arizona · 11.7 MI W JCT US 191 · Structure no. 01421

Built
1932
93 years old, rebuilt 1952
Condition
Fair
inspected August 2023
Type
Slab
Concrete
Length
22 ft
1 main span
Daily traffic
3,757
2022 count
Owner
State
State Highway Agency

About this bridge

IRR US 70 over Patterson Wash is a concrete slab carrying IRR US 70 over Patterson Wash in Graham County, Arizona. It was built in 1932 and reconstructed in 1952, so it is 93 years old, older than the Arizona average of 47.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 3,757 vehicles a day, roughly 27% of them trucks, projected to reach 3,767 by 2042. The structure is 22 ft (6.7 m) long and 51 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

Location

Open in Google Maps
CarriesIRR US 70
CrossesPatterson Wash
Location11.7 MI W JCT US 191
RouteU.S. Route 70
CountyGraham County
StateArizona
Coordinates32.92017, -109.86857
Functional classRural Minor Arterial

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation6: Equal to present minimum criteria
Deck geometry9: Superior to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating67 US tons
Inventory rating40 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length22 ft (6.7 m)
Longest span21 ft (6.4 m)
Deck width51 ft (15.5 m)
Roadway width48 ft (14.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,757 (2022)
Projected traffic3,767 by 2042
Trucks27%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.8 mi (159 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$1,000 (2019 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was IRR US 70 over Patterson Wash built?

It was built in 1932, making it 93 years old in 2025. It was reconstructed in 1952.

What condition is IRR US 70 over Patterson Wash in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in August 2023.

How much traffic does IRR US 70 over Patterson Wash carry?

About 3,757 vehicles per day (2022 count), of which roughly 27% are trucks.

How long is IRR US 70 over Patterson Wash?

The structure is 22 ft (6.7 m) long with a longest span of 21 ft (6.4 m) and a deck 51 ft wide.

Who owns IRR US 70 over Patterson Wash?

It is owned by the State Highway Agency.