The Phoenix Bypass Route is an informal designation for a highway combination in the U.S. state of Arizona that allows long-distance motorists to avoid traveling through the central Phoenix metropolitan area. The route consists of Interstate 8 (I-8) between Casa Grande and Gila Bend, and State Route 85 (SR 85) between Gila Bend and Buckeye, where it reconnects with Interstate 10 (I-10).
The combination of SR 85 between I-10 and I-8, together with I-8 between SR 85 and I-10 near Casa Grande, has been promoted as a bypass of the Phoenix area for long-distance travelers on I-10, particularly for traffic between southern California and Tucson or points farther east.
Route description
Interstate 8 segment
The bypass begins at I-10 southeast of Casa Grande, where motorists exit onto I-8 westbound. I-8 is an east–west Interstate Highway running from San Diego to its eastern terminus at I-10 near Casa Grande. In Arizona, I-8 crosses the Sonoran Desert, passing near communities such as Stanfield and Dateland.
Approaching Gila Bend, I-8 maintains a generally northeastern heading before reaching its junction with SR 85. West of this interchange, I-8 continues toward Yuma and California; east of the Casa Grande area, it terminates at I-10.
State Route 85 segment
At Gila Bend, traffic leaves I-8 and proceeds north on SR 85. Within Gila Bend, SR 85 intersects the I-8 business loop and provides access to local facilities including Gila Bend Municipal Airport. The highway then turns northeast and continues toward the Phoenix metropolitan area.
North of Gila Bend, SR 85 runs near the western edge of the Sonoran Desert National Monument and provides access to Buckeye Hills Regional Park. This segment is part of the National Highway System. As it approaches Buckeye, SR 85 crosses the Gila River and the Buckeye Canal before reaching its northern terminus at Exit 112 on I-10.
Function
The Phoenix Bypass Route is used primarily by:
Westbound traffic from Tucson or eastern Arizona heading toward Yuma or San Diego. Eastbound traffic from southern California bound for Tucson, New Mexico, or Texas. Commercial freight traffic seeking to avoid congestion within central Phoenix.
By diverting at Casa Grande onto I-8 and reconnecting with I-10 at Buckeye via SR 85, motorists can circumvent urban traffic, construction zones, and peak-period congestion commonly experienced along I-10 through downtown Phoenix.
Exit list I-8 segment (Casa Grande to Gila bend)
SR 85 segment (Gila Bend to Buckeye)
Exit numbers reflect mileposts on former .
Planned Gila Bend-Buckeye realignment
See also Interstate 8 in Arizona Arizona State Route 85 Interstate 10 in Arizona Phoenix metropolitan area
References