US Bridges

SR 79 over Tom Mix Wash

Good

Pinal County, Arizona · 24.4 MI N JCT SR 77 · Structure no. 04749

Built
1946
79 years old
Condition
Good
inspected March 2022
Type
Culvert
Concrete Continuous
Length
64 ft
6 main spans
Daily traffic
2,829
2021 count
Owner
State
State Highway Agency

About this bridge

SR 79 over Tom Mix Wash is a concrete continuous culvert carrying SR 79 over Tom Mix Wash in Pinal County, Arizona. It was built in 1946, so it is 79 years old, older than the Arizona average of 47.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 2,829 vehicles a day, roughly 11% of them trucks, projected to reach 2,839 by 2041. The structure is 64 ft (19.5 m) long and 33 ft wide. If it were closed, the detour would be 65.2 mi (105 km).

Location

Open in Google Maps
CarriesSR 79
CrossesTom Mix Wash
Location24.4 MI N JCT SR 77
RouteState Highway 79
CountyPinal County
StateArizona
Coordinates32.825, -111.2064
Functional classRural Minor Arterial

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Channel and channel protection7 GoodSome minor problems.
Culvert7 GoodSome minor problems.
Last inspectionMarch 2022
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating55 US tons
Inventory rating33 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans6
Design loadHS 20
Structure length64 ft (19.5 m)
Longest span10 ft (3 m)
Deck width33 ft (10 m)
Roadway width31 ft (9.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,829 (2021)
Projected traffic2,839 by 2041
Trucks11%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed65.2 mi (105 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 (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was SR 79 over Tom Mix Wash built?

It was built in 1946, making it 79 years old in 2025.

What condition is SR 79 over Tom Mix Wash in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in March 2022.

How much traffic does SR 79 over Tom Mix Wash carry?

About 2,829 vehicles per day (2021 count), of which roughly 11% are trucks.

How long is SR 79 over Tom Mix Wash?

The structure is 64 ft (19.5 m) long with a longest span of 10 ft (3 m) and a deck 33 ft wide.

Who owns SR 79 over Tom Mix Wash?

It is owned by the State Highway Agency.