Arizona State Route 303
|Bob Stump Memorial Parkway|
|Maintained by ADOT|
|Length:||35.25 mi (56.73 km)|
|Existed:||1985 – present|
|CCW end:||I‑10 in Goodyear|
|US 60 in Surprise|
|CW end:||I‑17 north of Phoenix|
Arizona State Route 303, also known as Loop 303 (spoken as three-oh-three) or Bob Stump Memorial Parkway formerly called Estrella Freeway, is a freeway that serves the northwestern portion of the Phoenix area. The freeway, originally a two-lane rural highway, was maintained by Maricopa County in central Arizona serving the far western suburbs of the Phoenix metropolitan area until 2004 when the Arizona Department of Transportation again took the control of upgrading the interim road to a freeway. As of 2004 it was renamed "Bob Stump Memorial Parkway" to honor former Arizona congressman Bob Stump.
Its route is from Interstate 10 in Goodyear to Interstate 17 south of Carefree Highway. Most of the current roadway has been upgraded to freeway standards. There is a short non freeway section from just north of Clear view Boulevard to El Mirage Road that will be updated by 2016.
Loop 303 currently begins at a stack interchange with I-10 in Goodyear. It heads north under McDowell and Thomas Roads, then over an interchange with Indian School Road. The road heads through a farmland terrain and passes the Wildlife World Zoo near Northern Avenue. It over passes the BNSF Railway near Olive Avenue. At an interchange with Greenway Road, Route 303 enters a residential community and turns northeast, becoming a two lane highway past Clearview Boulevard. The route heads over a bridge above Grand Avenue (US 60) (access given by temporary connector road) along with another BNSF railroad line. The route turns eastward and becomes a 4-lane limited-access highway (which will eventually be upgraded to a 6-lane freeway). It then becomes a controlled-access highway at El Mirage Road. It turns north near the Happy Valley Parkway interchange and then east again south of Lake Pleasant, passing through planned arterial interchanges. The freeway comes to an end at a temporary at-grade interchange (eventually to be a stack interchange with I-17 near Skunk Creek. East of this interchange, Route 303 will become Sonoran Desert Drive. 
Loop 303 was originally a part of the 1985 Maricopa County Regional Transportation Plan to be funded by a sales tax approved by Maricopa County voters. The freeway, designed to service the Northwest Valley, would have been completed sometime by 2014. However, funding shortfalls and increasing construction costs forced cutbacks in the plan, and in 1995 the freeway was dropped from the regional plans.
Maricopa County took charge of what was then called the Estrella Freeway project when it was dropped from the regional freeway plans, maintaining it as an interim 2-lane highway along the original corridor while keeping the state route designation. The county has made significant improvements to the roadway, extending it several miles north and east of US 60. While the highway is still largely a 2-lane rural road, the extension north of US 60 along with the southern terminus just north of Interstate 10 have been upgraded to a 4-lane divided parkway, and the segment between US 60 and Bell Road in Surprise has been partially upgraded to controlled-highway standards with overpasses and right-of-way for on-ramps.
With the extension of the sales tax approved in 2004, the highway has once again been added to the Regional Transportation Plan. As Maricopa County has completed much of the required study and preparation work, construction on the freeway is already underway with a planned completion date of the I-10 to I-17 segment by 2015. In mid-2011 the segment between Happy Valley Parkway and I-17 was completed as a four-lane highway with an interchange at Lone Mountain Parkway completed but closed to the public. Motorists must pass through a signaled interchange until a freeway to freeway interchange is built between Loop 303 and I-17. According to a recent agreement between the state legislature and the state department of transportation, STAN (Statewide Transportation Acceleration Needs) funds were used to build a partial interchange at Bell Road in summer 2010, several years before previously intended.
Long-term plans call for the extension of Loop 303 south of the interchange with I-10 in Goodyear to the planned I-10 'Reliever Route' Freeway, SR 30, and continuing south through Goodyear to connect with the planned alignment of future Interstate 11. Loop 303 would run concurrent with I-11 for several miles, before splitting off southward towards its ultimate terminus at Interstate 8 west of Casa Grande. If completed, Loop 303 will serve as a Phoenix bypass route for the southwestern suburbs of Goodyear, Avondale, and Buckeye as well as an alternate Phoenix bypass route for I-10 traffic headed westbound to the Greater Los Angeles Area and northbound via I-17 to Flagstaff.
In response to a projected budget shortfall of $6.6 billion brought on by the recession, the Maricopa Association of Governments voted to suspend funding to numerous projects during a meeting on October 28, 2009. Some modifications to Route 303, such as a scaled-back design of its interchanges with I-10 and US Highway 60, were made to cope with the budget shortfall. Funding for the extension south of I-10 to the planned alignment of SR 30 was removed, effectively postponing the extension until after 2025.
The entire route is in Maricopa County.
|Goodyear||SR 30 (I-10 Reliever)||Future interchange; construction begins in 2023|
|Baseline Road||Future interchange; construction begins in 2023|
|Southern Avenue||Future interchange; construction begins in 2023|
|Buckeye Road||Future interchange; construction begins in 2023|
|Yuma Road||Future interchange; construction begins in 2016|
|3.80||6.12||–||Cotton Lane / Van Buren Street||Former southern terminus|
|3.93||6.32||104||I‑10 – Phoenix, Los Angeles, CA||Stack interchange opened August 2014, frontage roads to be opened September|
|4.14||6.66||–||McDowell Road||Former at-grade intersection; possible future interchange|
|5.19||8.35||105||Thomas Road / Cotton Lane||Southbound exit and northbound entrance; Temporary southern terminus|
|6.19||9.96||106||Indian School Road|
|Goodyear–Glendale line||7.19||11.57||107||Camelback Road|
|Glendalea||8.19||13.18||108||Bethany Home Road||Interchange opened June 2014|
|9.19||14.79||109||Glendale Avenue||Interchange opened Spring 2014|
|10.19||16.40||110A||Northern Avenue||Northbound exit and southbound entrance|
|110B||Northern Parkway east||Trumpet Interchange|
|Glendale–Surprise line||12.20||19.63||112||Peoria Avenue|
|Surprise–Sun City West line||19.33||31.11||119||US 60 (Grand Avenue)||Access via temporary connector road; interchange construction to begin )late 2014|
|Sun City West||21.20||34.12||121||El Mirage Road||At-grade intersection; interchange construction to begin in 2015|
|Peoria||24.81||39.93||125||Happy Valley Parkway / Vistancia Boulevard|
|126||Jomax Parkway||Planned interchange|
|26.31||42.34||127||Lone Mountain Parkway|
|128||Westland Drive||Planned Interchange|
|27.81||44.76||131||Lake Pleasant Parkway|
|Phoenix||30.95||49.81||133||Pyramid Peak Parkway (67th Avenue)||Planned interchange|
|32.23||51.87||135||Stetson Valley Parkway (51st Avenue)||Planned interchange|
|34.23||55.09||137||35th Avenue||Planned Interchange (with Frontage Roads|
|35.23||56.70||I‑17 / Sonoran Desert Drive – Flagstaff, Phoenix||Northern terminus at an at-grade intersection (future Sonoran Desert Drive/303 Frontage Roads); site of future stack interchange|
|1.000 mi = 1.609 km; 1.000 km = 0.621 mi
- Arizona Department of Transportation. "2008 ADOT Highway Log". Retrieved April 8, 2008.
- "MCDOT Rightroads Program".
- "Maricopa County Board of Supervisors minute book".
- Arizona Department of Transportation (September 2011). Arizona Railroads (Map). Cartography by Multimodal Planning Division. http://www.azdot.gov/mpd/gis/maps/pdf/railroads.pdf. Retrieved April 9, 2012.
- Google Inc. "SR 303". Google Maps (Map). Cartography by Google, Inc. http://maps.google.com/maps?saddr=AZ-303+Loop+N%2FN+Cotton+Ln&daddr=AZ-303+Loop&hl=en&ll=33.657495,-112.157364&spn=0.539533,1.056747&sll=33.77344,-112.11874&sspn=0.067351,0.132093&geocode=FSuV_gEd0IBM-Q%3BFYxGAwId1gdR-Q&mra=me&mrsp=1,0&sz=14&t=m&z=11. Retrieved April 9, 2012.
- "Loop 303 (North of I-10)". ADOT. Archived from the original on 8 February 2008. Retrieved 2008-02-02.
- "L303 Overview". ADOT. Archived from the original on 8 February 2008. Retrieved 2008-02-02.
- "Interstate11.org". Retrieved 2012-08-17.
- Holstege, Sean (2009-10-29). "Valley freeway projects shelved". The Arizona Republic. Retrieved 2009-11-04.