US Bridges

FSR 708 over Boulder Canyon

Fair

Yavapai County, Arizona · 8 MI W/O Strawberry · Structure no. 030401000004121

Built
1959
66 years old
Condition
Fair
inspected August 2023
Type
Tee Beam
Concrete
Length
42 ft
1 main span
Daily traffic
300
2021 count
Owner
Federal
U.S. Forest Service

About this bridge

FSR 708 over Boulder Canyon is a concrete tee beam carrying FSR 708 over Boulder Canyon in Yavapai County, Arizona. It was built in 1959, so it is 66 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 5 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 300 vehicles a day, roughly 5% of them trucks, projected to reach 399 by 2040. The structure is 42 ft (12.7 m) long and 23 ft wide. If it were closed, the detour would be 59.7 mi (96 km).

Location

Open in Google Maps
CarriesFSR 708
CrossesBoulder Canyon
Location8 MI W/O Strawberry
RouteFederal Lands Road 708
CountyYavapai County
StateArizona
Coordinates34.39495, -111.65021
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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; action required to protect exposed foundations
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment3: Basically intolerable, requiring high priority of corrective action
Operating rating41.1 US tons
Inventory rating29.7 US tons

Structure

Structure typeTee Beam
MaterialConcrete
DeckConcrete, precast panels
Main spans1
Design loadHS 20
Structure length42 ft (12.7 m)
Longest span41 ft (12.4 m)
Deck width23 ft (6.9 m)
Roadway width20 ft (6.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic300 (2021)
Projected traffic399 by 2040
Trucks5%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed59.7 mi (96 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 proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$100,000
NavigationNo navigation control on waterway

Frequently asked questions

When was FSR 708 over Boulder Canyon built?

It was built in 1959, making it 66 years old in 2025.

What condition is FSR 708 over Boulder Canyon 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 FSR 708 over Boulder Canyon carry?

About 300 vehicles per day (2021 count), of which roughly 5% are trucks.

How long is FSR 708 over Boulder Canyon?

The structure is 42 ft (12.7 m) long with a longest span of 41 ft (12.4 m) and a deck 23 ft wide.

Who owns FSR 708 over Boulder Canyon?

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