Arizona State Route 30

State Route 30 (SR 30), also known as the Tres Rios Freeway, is a planned freeway in the southwest part of the Phoenix metropolitan area. It is planned as a reliever for Interstate 10 five miles (8 km) to the north and will run through the communities of Buckeye, Goodyear, Avondale, and Phoenix.

In earlier planning stages, the freeway was referred to as State Route 801 (SR 801).

SR 30 will have three segments: a western segment from SR 85 to Loop 303, a central segment from Loop 303 to Loop 202, and an eastern segment from Loop 202 to I-17.

SR 30 is planned to begin at SR 85 along the Hazen Road alignment, about one mile (1.6 km) south of downtown Buckeye. It will then travel northeast for 10 miles (16 km) before intersecting Loop 303 between Broadway Road and Southern Avenue in Goodyear. SR 30 will then head east for five miles (8 km) before turning southeast at the Agua Fria River and running along the Southern Avenue alignment for 2.5 miles (4.0 km). While along the Southern Avenue alignment, frontage roads will accompany the road to provide access to local communities. SR 30 will then head back northeast for 7 miles (11 km) before intersecting Loop 202 just south of Broadway Road in Phoenix. SR 30 will then continue to travel northeast for 4.5 miles (7.2 km) before meeting its eastern terminus by intersecting the Interstate 17 at the Durango Curve in Phoenix. SR 30 will be 29 miles (47 km) in length when fully complete.

A freeway along the planned SR 30 corridor, titled the Buckeye Expressway, was originally proposed in 1957 as the planned route for Interstate 10 into Phoenix. This plan was later abandoned, and I-10 was re-routed northwards along the present Papago Freeway alignment.

In November 2004, Maricopa County voters approved an extension to an existing sales tax funding regional transportation improvements. A significant portion of those funds will go toward improvements of I-10, which experiences significant volumes of traffic in the southwest part of the Valley. However, rapid growth in the neighboring communities of Buckeye, Goodyear, and Avondale is expected to worsen the congestion on I-10, necessitating the construction of a reliever route.

The Arizona Department of Transportation (ADOT) first identified the need for a route along the current SR 30 corridor in June 2005. The route was planned to run parallel 5 miles (8 km) south of I-10 through the cities to provide relief. It would run through largely undeveloped land, reducing the impact on residential communities. Due to the extension of the sales tax in 2004, funds were available to help build SR 30.

In response to a budget shortfall brought on by the Great Recession, the Maricopa Association of Governments (MAG) voted to suspend funding to numerous projects in October 2009, including SR 30. While not removing SR 30 from the long-term regional transportation plan, the removal of the funding would effectively postpone the construction of the route until at least 2026. The plan had originally indicated a construction timeline between 2021 and 2025.