US Bridges

I 17 over Cap Aqueduct

Fair

Maricopa County, Arizona · 3.6 MI South JCT SR 74 · Structure no. 01400

Built
1977
48 years old, rebuilt 2009
Condition
Fair
inspected December 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
87 ft
1 main span
Daily traffic
120,612
2022 count
Owner
State
State Highway Agency

About this bridge

I 17 over Cap Aqueduct is a prestressed concrete stringer/multi-beam or girder carrying I 17 over Cap Aqueduct in Maricopa County, Arizona. It was built in 1977 and reconstructed in 2009, so it is 48 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 120,612 vehicles a day, roughly 6% of them trucks, projected to reach 120,622 by 2042. The structure is 87 ft (26.5 m) long and 149 ft wide.

Location

Open in Google Maps
CarriesI 17
CrossesCap Aqueduct
Location3.6 MI South JCT SR 74
RouteInterstate 17
CountyMaricopa County
StateArizona
Coordinates33.74668, -112.1246
Functional classUrban Principal Arterial - Interstate

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.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection7 GoodSome minor problems.
Last inspectionDecember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourCountermeasures installed to correct a previously existing problem
Structural evaluation8: Equal to present desirable criteria
Deck geometry9: Superior to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating96 US tons
Inventory rating43 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length87 ft (26.5 m)
Longest span85 ft (25.9 m)
Deck width149 ft (45.4 m)
Roadway width142 ft (43.4 m)
Vertical clearance over deck20 ft (6.1 m)

Traffic and service

Average daily traffic120,612 (2022)
Projected traffic120,622 by 2042
Trucks6%
Lanes on structure8
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed—
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was I 17 over Cap Aqueduct built?

It was built in 1977, making it 48 years old in 2025. It was reconstructed in 2009.

What condition is I 17 over Cap Aqueduct 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 December 2024.

How much traffic does I 17 over Cap Aqueduct carry?

About 120,612 vehicles per day (2022 count), of which roughly 6% are trucks.

How long is I 17 over Cap Aqueduct?

The structure is 87 ft (26.5 m) long with a longest span of 85 ft (25.9 m) and a deck 149 ft wide.

Who owns I 17 over Cap Aqueduct?

It is owned by the State Highway Agency.