US Bridges

SR B8 over Gillespie IRR Canal

Fair

Maricopa County, Arizona · 0.05 MI W JCT SR 85 · Structure no. 00465

Built
1956
69 years old
Condition
Fair
inspected February 2024
Type
Slab
Concrete Continuous
Length
61 ft
3 main spans
Daily traffic
15,358
2022 count
Owner
State
State Highway Agency

About this bridge

SR B8 over Gillespie IRR Canal is a concrete continuous slab carrying SR B8 over Gillespie IRR Canal in Maricopa 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 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 15,358 vehicles a day, roughly 14% of them trucks, projected to reach 15,368 by 2042. The structure is 61 ft (18.6 m) long and 88 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesSR B8
CrossesGillespie IRR Canal
Location0.05 MI W JCT SR 85
RouteState Highway 8
CountyMaricopa County
StateArizona
Coordinates32.9503, -112.7007
Functional classRural Principal Arterial - Other

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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionFebruary 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry9: Superior to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating41 US tons
Inventory rating24 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length61 ft (18.6 m)
Longest span22 ft (6.7 m)
Deck width88 ft (26.8 m)
Roadway width76 ft (23.2 m)
Vertical clearance over deck25 ft (7.6 m)

Traffic and service

Average daily traffic15,358 (2022)
Projected traffic15,368 by 2042
Trucks14%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemYes

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$2,000 (2024 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was SR B8 over Gillespie IRR Canal built?

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

What condition is SR B8 over Gillespie IRR Canal 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 February 2024.

How much traffic does SR B8 over Gillespie IRR Canal carry?

About 15,358 vehicles per day (2022 count), of which roughly 14% are trucks.

How long is SR B8 over Gillespie IRR Canal?

The structure is 61 ft (18.6 m) long with a longest span of 22 ft (6.7 m) and a deck 88 ft wide.

Who owns SR B8 over Gillespie IRR Canal?

It is owned by the State Highway Agency.