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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 I-11 Final Tier 1 Environmental Impact Statement and Preliminary Section 4(f) Evaluation (Final Tier 1 EIS) was completed and made available for public review (Final Tier 1 EIS document) July 16 through August 16, 2021. To learn more, visit the Overview page.

Zoom in on a satellite view of the Preferred Alternative.

The next major milestone for this study is the publication of a 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.

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.