US Bridges

Onion Saddle over South Fork of Cave Creek

Fair

Cochise County, Arizona · 3.3 MI Sw/O Portal Fire & · Structure no. 030501000003260

Built
1956
69 years old
Condition
Fair
inspected August 2024
Type
Slab
Concrete
Length
25 ft
1 main span
Daily traffic
85
2022 count
Owner
Federal
U.S. Forest Service

About this bridge

Onion Saddle over South Fork of Cave Creek is a concrete slab carrying Onion Saddle over South Fork of Cave Creek in Cochise County, Arizona. It was built in 1956, so it is 69 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 85 vehicles a day, projected to reach 125 by 2040. The structure is 25 ft (7.5 m) long and 30 ft wide. If it were closed, the detour would be 24.9 mi (40 km).

Location

Open in Google Maps
CarriesOnion Saddle
CrossesSouth Fork of Cave Creek
Location3.3 MI Sw/O Portal Fire &
RouteFederal Lands Road 42
CountyCochise County
StateArizona
Coordinates31.88339, -109.17559
Functional classRural Local

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 protection7 GoodSome minor problems.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating26.5 US tons
Inventory rating20.4 US tons

Structure

Structure typeSlab
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length25 ft (7.5 m)
Longest span23 ft (7.1 m)
Deck width30 ft (9.1 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic85 (2022)
Projected traffic125 by 2040
Trucks—
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed24.9 mi (40 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerU.S. Forest Service
Maintained byU.S. Forest Service
Historic statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Onion Saddle over South Fork of Cave Creek built?

It was built in 1956, making it 69 years old in 2025.

What condition is Onion Saddle over South Fork of Cave Creek 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 2024.

How much traffic does Onion Saddle over South Fork of Cave Creek carry?

About 85 vehicles per day (2022 count).

How long is Onion Saddle over South Fork of Cave Creek?

The structure is 25 ft (7.5 m) long with a longest span of 23 ft (7.1 m) and a deck 30 ft wide.

Who owns Onion Saddle over South Fork of Cave Creek?

It is owned by the U.S. Forest Service.