Transportation Conformity

Transportation Conformity

Transportation Conformity ensures that transportation plans, programs and projects do not produce new air-quality violations, worsen existing violations or delay timely attainment of the National Ambient Air Quality Standards (NAAQS).

The ADOT Air Quality Team is responsible for implementing and developing the statutory and regulatory requirements for conformity state implementation plans (conformity SIPs). A conformity SIP includes a state's specific criteria and procedures for certain aspects of the transportation conformity process. Clean Air Act section 176(c) is the statutory authority for transportation conformity (42 U.S.C. 7506(c)). The regulations that explain the requirements for a conformity SIP are found at 40 CFR 51.390, which was updated Jan. 24, 2008 (73 FR 4420).

Project Level Conformity

Project Level Conformity Hot-Spot Analysis

Completed Project Level Hot-Spot modeling and associated consultation documents required for hot-spot modeling will be posted here as applicable.

Project Level Conformity Consultation 

Completed Project Level Project of Air Quality Concern (POAQC) and interagency consultation documents will be posted here as applicable.

Isolated Rural Area Conformity Documents

The U.S. Environmental Protection Agency (EPA) transportation conformity regulations requires certain projects in nonattainment areas to engage in interagency consultation and complete PM2.5/PM10  analyses as part of the project-level conformity determination process.  In rural areas, interagency consultation on regional and project level conformity required for federal funded transportation projects is conducted through the ADOT’s Environmental Planning Air Quality staff.  

Transportation Conformity also requires that FHWA/FTA projects in PM10 and PM2.5 nonattainment and maintenance areas demonstrate that during the time frame of the transportation plan no new local violations will be created and the severity or number of existing violations will not be increased as a result of the project, and the project has been included in a regional emissions analysis that meets applicable §§ 93.118 and/or 93.119 requirements. The demonstration must be performed according to the consultation requirements of § 93.105(c)(1)(i) and the methodology requirements of § 93.123.

Douglas International Commercial Port-of-Entry Connector Road Study

The Arizona Department of Transportation, in coordination with the Federal Highway Administration, US General Services Administration (GSA), the city of Douglas and Cochise County, is evaluating alternatives for a connector road from the new Douglas International Port of Entry (IPOE) to State Route 80. ADOT is currently developing a regional and project level conformity analysis for this project located in the Paul Spur/Douglas | PM-10 Nonattainment Area. ADOT requested comments on the draft documents provided through the Environmental Assessment on the Project Page. A public hearing was held Nov. 19 to provide an overview of the draft Environmental Assessment and the Design Concept Report (DCR), share ADOT’s recommended alternative for a connector road and receive public comments. Public comments were accepted through Dec. 9, 2024, through the online comment form, mail, telephone and email. (Refer to Appendix A Air Quality)

Prior Draft Documents,

State Route 189 Study: International Border to Grand Avenue project

ADOT provided the draft Arizona Department of Transportation Air Quality Regional Conformity Analysis Nogales Nonattainment for review and comment through May 22nd , 2017, no comments were received.

Prior Draft Documents include: