Transportation Studies

Interstate 10 / Houghton Traffic Interchange Study

The Arizona Department of Transportation (ADOT), in partnership with the Federal Highway Administration (FHWA), has initiated a design concept study and related environmental studies to evaluate an interchange reconstruction at Houghton Road and Interstate 10 in Tucson, Arizona.

Considerable growth is anticipated along the Interstate 10 (I-10) corridor in the coming years, with projections indicating volumes will increase by 50% by 2045. Similarly, Houghton Road expects substantial increases in traffic, with projections showing a 500% increase north of I-10 and 200% increase south of I-10. The reconstructed interchange would provide relief for motorists accessing existing and planned residential and business developments in the surrounding areas.

The purpose of this study is to develop and evaluate options to reconstruct the traffic interchange (TI) at Houghton Road and recommend an alternative that will meet long-term transportation needs, satisfy the requirements of the National Environmental Policy Act (NEPA), and obtain public support.

This study will address the following improvements:

  • A reconstructed TI at Houghton Road to accommodate projected traffic volumes and provide full highway access (including parallel-type entrance and exit ramps in both directions), and
  • Reconstructed Houghton Road from north of Rocket Road to south of I-10.

Houghton Road is a principal arterial road that serves north-south traffic in the southeastern part of Tucson and Pima County. It provides access to the Pima County Fairgrounds (one mile south of I-10) and several businesses and residential areas (several miles north and south of I-10). The land adjacent to Houghton Road north and south of I-10 is owned by the State of Arizona and is undeveloped. The nearest access points to and from I-10 in this area are provided via the Rita Road TI approximately two miles to the west (MP 273.14) and the Wentworth Road – Colossal Cave Road TI approximately four miles to the east (MP 279.37). The Houghton Road TI is at MP 275.49.

If you’re curious to see how a DDI works, watch this video from the Illinois Department of Transportation (IDOT). Recently IDOT constructed a DDI at I-88 and Route 59 near Chicago. This DDI’s design is similar to what is being planned for I-10/Houghton Rd TI.

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Civil Rights

Pursuant to Title VI of the Civil Rights Act of 1964, the Americans with Disabilities Act (ADA) and other nondiscrimination laws and authorities, ADOT does not discriminate on the basis of race, color, national origin, sex, age, or disability. Persons that require a reasonable accommodation based on language or disability should contact ADOT’s Civil Rights Office at Requests should be made as early as possible to ensure the State has an opportunity to address the accommodation.

De acuerdo con el Título VI de la Ley de Derechos Civiles de 1964, la Ley de Estadounidenses con Discapacidades (ADA por sus siglas en inglés) y otras normas y leyes antidiscriminatorias, el Departamento de Transporte de Arizona (ADOT) no discrimina por motivos de raza, color, origen nacional, sexo, edad o discapacidad. Las personas que requieran asistencia (dentro de lo razonable) ya sea por el idioma o discapacidad deben ponerse en contacto con la Oficina de Derechos Civiles de ADOT en Las solicitudes deben hacerse lo más antes posible para asegurar que el Estado tenga la oportunidad de hacer los arreglos necesarios.