Project Overview

Alternatives for Further Study

The Study Team began with more than 30 alternatives to evaluate for the South Mountain Freeway corridor. Those alternatives comprised the two segments of the proposed freeway: east and west. The split between the east and west alternatives selected for further study lies just east of 59th Avenue and south of Elliot Road.

The western section was narrowed to three alternatives: W55, W71 and W101. The W55 alternative would connect to I-10 at roughly 55th Avenue, W71 at 71st Avenue, and W101 at the existing Loop 101/I-10 system interchange.

There is one action alternative in the eastern section, E1. It generally follows the same alignment as in the 1988 Design Concept Report and connects to I-10 at the Pecos Road/I-10/Loop 202 Santan Freeway system interchange. ADOT remains committed to evaluating other alternatives in the eastern segment should any become available for study.

Identifying the Alternatives

Numerous potential alternatives have been suggested. Early in the study, workshops were held with citizens; civic organizations; the Ahwatukee, Estrella, Laveen and South Mountain village planning committees; Maricopa County Farm Bureau; and the Southwest Mayors and Managers group. Participants were invited to draw alignments on study area maps and aerial photos, and to indicate cultural or environmental constraints. From these workshops more than 30 potential alternatives were identified for the entire corridor.

These 30 public alternatives were grouped into corridors for review by the technical team, which then narrowed them to nine “Technical Alternatives.” The nine alignments were presented to the potentially affected local jurisdictions, including Tolleson, Avondale, Goodyear, Chandler, Phoenix, Maricopa County, MAG and the Gila River Indian Community (GRIC).

Where Could it Connect to I-10 West?

After more than four years of complex technical study and hundreds of meetings with citizens, elected officials and others, alternatives were evaluated in great detail for potential connections to I-10 west near 55th Avenue, 71st Avenue or at the existing Loop 101 connection.

What Are the Major Differences in These Connections?

The 55th Avenue, 71st Avenue, and Loop 101 connections differ in their proximity to downtown Phoenix. They each have different social and economic impacts to the neighborhoods, and each would affect traffic differently along I-10 and other segments of the Regional Freeway System.

All three alternatives cross a variety of existing and proposed land uses. Some have greater impacts to future residential lands while others impact future commercial or industrial property. Future land uses have been planned near the original 55th Avenue alignment, which is similar to the alignment proposed in the mid- to late-1980s. All three alternatives could result in residential and business relocations.

Traffic would operate differently for each alternative. Based on initial traffic projections for the year 2030:

• 50 percent of the traffic on a South Mountain connection to I-10 at 55th Avenue would come from or go to the east (downtown Phoenix) on I-10. With a connection to I-10 at 71st Avenue, about 40 percent of the South Mountain Freeway traffic would head to the east on I-10.
   
• With a connection to I-10 at the Loop 101, about 33 percent of the South Mountain Freeway traffic would travel to and from the east on I-10, with most of the remaining vehicles using the Loop 101.

In 2006, ADOT determined that the W55 alignment would be carried forward in the study process as the “preliminary preferred alternative” for the western segment of the proposed freeway. ADOT’s preliminary selection of this alignment was based on regional support, historical establishment, community considerations and traffic demands for the region.

Where Would it Connect to I-10 East?

If built, the South Mountain Freeway would likely connect to I-10 east at the current interchange of I-10 and Loop 202 (Santan Freeway). The only option available at this time would have a freeway follow the Pecos Road alignment, remaining just north of the boarder between Phoenix and the GRIC. The Pecos Road alignment was first proposed in the mid-1980s.

Gila River Indian Community

Since the beginning of the study in 2001, ADOT and FHWA have been working with the GRIC to determine if a portion of a freeway might be located on community land to the south of Pecos Road. To date, no GRIC options have been approved by the community for further study.

GRIC has sole authority to decide if and where a freeway might be studied or built on its land. Therefore, if an eastern preference must be identified without GRIC alternatives, options would include either the Pecos Road alignment or not building the South Mountain Freeway.

Is Not Building the Freeway Really an Option?

Not building a freeway remains an option. If this option is selected, the proposed project would not take place and the environmental effects from taking no action would be evaluated. It is possible, however, that a new study for the area could be initiated at some point in the future. While ADOT has been charged to study the proposed South Mountain Freeway by the Maricopa Association of Governments, the regional transportation planning body, ADOT has not taken a formal position on the roadway and will not do so until the study is complete and all alternatives evaluated.

Background on the Alternatives

Need Exists for South Mountain Freeway

An extensive analysis of population trends, land use plans and travel demand shows clearly that there is a traffic problem in the Southwest and Southeast areas of the Valley. Congestion will continue to worsen if transportation plans fail to appropriately address increases in population and vehicles.

At this point in the study process it has been determined that while planned transit and roadway improvements must be part of the solution to the Valley's future transportation needs, a purpose and need exists to include a new freeway in the South Mountain Corridor., The no-build option, however, remains an alternative.

The process of identifying alternative routes for the South Mountain Freeway has included local governments, businesses, MAG, the GRIC and the general public. The process began with a public “scoping” phase, during which a number of alternatives, enhanced transit options and several conceptual alignments were proposed.

Documents are posted as they become available in PDF format, which requires Adobe Reader to view.

Our Valley Freeway System is part of the 2004 voter-approved Regional Transportation Plan. We are working hard with our transit partners to implement the voters’ vision and are committed to quality, safety, open communication with our neighbors, and minimal inconvenience to the traveling public.