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Interstate 11 Corridor Tier I Environmental Impact Statement

The initial I-11 and Intermountain West Corridor Study was completed in 2014. This allowed Interstate 11 (I-11) efforts to move to the next phase, with projects and studies continuing in both Arizona and Nevada.

Arizona is continuing the process through a Tier 1 Environmental Impact Statement (EIS) Study to potentially identify a Selected Corridor Alternative between Nogales and Wickenburg, Arizona.

The Interstate 11 (I-11) Final Tier 1 Environmental Impact Statement and Preliminary Section 4(f) Evaluation (Final Tier 1 EIS) is now available for public review on the Documents page. The public review period for the Final Tier 1 EIS is 30 days and will run from July 16 through August 16, 2021. To learn more, visit the Overview page. The range of alternatives evaluated in the Final Tier 1 EIS includes both Build Corridor Alternatives and the No Build Alternative. The Final Tier 1 EIS outlines a Preferred Corridor Alternative that is a Build Corridor Alternative.

Zoom in on a satellite view of the Preferred Alternative.

The next major milestone for this study following the publication of the Final Tier 1 EIS is the Record of Decision, which will identify a Selected Corridor Alternative and is expected to be published before the end of 2021. This will mark the end of the Tier 1 EIS Study.

Comments on the Draft Tier 1 EIS Study can be made at any time during the study process. For more information, visit the Contact Us page.

In Nevada, the Regional Transportation Commission of Southern Nevada (RTC) led the effort to complete I-11 from US-95 to US-93 near the Hoover Dam Bypass Bridge, approximately 12.5 miles (Phase 1), while the Nevada Department of Transportation (NDOT) constructed the portion of I-11 from Railroad Pass to US-95, approximately 2.5 miles (Phase 2). Both phases were built simultaneously beginning in the spring of 2015 with construction completed in 2018.