US Bridges

US 70 over San Simon River

Fair

Graham County, Arizona · 3.9 MI E JCT US191 · Structure no. 00310

Built
1923
102 years old, rebuilt 1948
Condition
Fair
inspected August 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
153 ft
1 main span
Daily traffic
6,912
2022 count
Owner
State
State Highway Agency

About this bridge

US 70 over San Simon River is a steel stringer/multi-beam or girder carrying US 70 over San Simon River in Graham County, Arizona. It was built in 1923 and reconstructed in 1948, so it is 102 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 6,912 vehicles a day, roughly 13% of them trucks, projected to reach 6,922 by 2042. The structure is 153 ft (46.6 m) long and 39 ft wide. If it were closed, the detour would be 34.8 mi (56 km).

Location

Open in Google Maps
CarriesUS 70
CrossesSan Simon River
Location3.9 MI E JCT US191
RouteU.S. Route 70
CountyGraham County
StateArizona
Coordinates32.81659, -109.64808
Functional classUrban 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
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure7 GoodSome minor problems.
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 geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating85 US tons
Inventory rating61 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length153 ft (46.6 m)
Longest span105 ft (32 m)
Deck width39 ft (11.9 m)
Roadway width34 ft (10.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,912 (2022)
Projected traffic6,922 by 2042
Trucks13%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed34.8 mi (56 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 proposedWidening with deck rehabilitation or replacement
Estimated improvement cost$1,000 (2021 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was US 70 over San Simon River built?

It was built in 1923, making it 102 years old in 2025. It was reconstructed in 1948.

What condition is US 70 over San Simon River 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 US 70 over San Simon River carry?

About 6,912 vehicles per day (2022 count), of which roughly 13% are trucks.

How long is US 70 over San Simon River?

The structure is 153 ft (46.6 m) long with a longest span of 105 ft (32 m) and a deck 39 ft wide.

Who owns US 70 over San Simon River?

It is owned by the State Highway Agency.