Notice of Availability
Finding of No Significant Impact
408-SPL-2024-0032
Associated with Tucson Diversion Channel I-10 Bridge Replacement Project
The U.S. Army Corps of Engineers (USACE) Los Angeles District has finalized a Finding of No Significant Impact (FONSI) for Section 408 project no. 408-SPL-2024-0032 associated with the Tucson Diversion Channel I-10 Bridge Replacement Project.
The Council on Environmental Quality (CEQ) National Environmental Policy Act (NEPA) implementing regulations allow for a Federal agency to adopt another agency’s environmental assessment (40 C.F.R. § 1506.3(c)). USACE Engineer Circular (EC) 1165-2-220 describes policy and procedural guidance for processing requests to alter USACE Civil Work projects pursuant to 33 USC Section 408. EC 1165-2-220 (Appendix D) strongly encourages USACE districts to adopt and/or incorporate by reference any NEPA documentation that may exist for the Federal project. USACE may adopt, in whole or in part, another Federal agency's draft or final EA. The responsibility for NEPA and other environmental law actions for this project was assigned to the Arizona Department of Transportation (ADOT) pursuant to 23 U.S.C. § 327, and the NEPA Assignment Memorandum of Understanding executed by the Federal Highway Administration (FHWA) and ADOT on April 16, 2019, which allows ADOT to serve as the lead federal agency on the project. When adopting all or portions of another agency’s EA, USACE is still responsible for developing a FONSI, as applicable, to document NEPA compliance for the Section 408 permission decision. This FONSI documents the USACE decision regarding the 408 permission request to alter the USACE Civil Works project.
The Arizona Department of Transportation (ADOT), through the Pima County Flood Control District (PCFCD), has requested permission from the USACE pursuant to Section 408 to alter the Tucson Diversion Channel, a USACE federally authorized Civil Works project (USACE Project) in the city of Tucson, Pima County, Arizona. The proposed alteration to the USACE Project involves the following: (i) removal and replacement of the existing single span I-10 bridges that span over the Tucson Diversion Channel, and (ii) removal of a section of the east bank slope paving of Tucson Diversion Channel to allow installation of a new 36 inch diameter storm drain pipe outfall (Section 408 Activity). The Section 408 Activity is a component of the Interstate 10 (I-10), Junction Interstate 19 (I-19) to Kolb Road and State Route (SR) 210, Golf Links Road to I-10 project.
In accordance with NEPA, ADOT’s Draft EA was released for public review on October 29, 2019, remained available for review until December 12, 2019, a public hearing was held on November 20, 2019, and ADOT issued a FONSI on August 6, 2020. A Reevaluation of the EA of 2019 was completed in July 2024. The USACE independently reviewed the EA and determined the EA sufficiently identifies and evaluates the environmental impacts related to the Section 408 Activity. Therefore, in accordance with 40 C.F.R. § 1506.3(c), USACE’s NEPA regulations at 33 C.F.R. Part 230, and EC 1165-2-220, the USACE adopted ADOT’s EA.
Click each link for the ADOT’s EA and the USACE’s FONSI:
ADOT’s 2020 Final EA: https://usace.contentdm.oclc.org/digital/collection/p16021coll7/id/27143
which is intended to be read in conjunction with its 2019 Draft EA: https://usace.contentdm.oclc.org/utils/getfile/collection/p16021coll7/id/27163
ADOT’s 2024 EA Reevaluation: https://usace.contentdm.oclc.org/utils/getfile/collection/p16021coll7/id/27165
USACE’s 2024 FONSI: https://usace.contentdm.oclc.org/digital/collection/p16021coll7/id/27166
For further information, please contact Priyo Majumdar USACE Los Angeles District by electronic mail at Priyodarshi.Majumdar@usace.army.mil or by telephone at (213) 364-0038.