In October 2023, the U.S. Department of Energy’s Grid Deployment Office selected Southline Transmission Project as part of a $1.3 billion commitment to improve electric transmission lines through the Transmission Facilitation Program.
Black Forest Partners and GU Southline LLC, a wholly-owned subsidiary of Grid United, are co-developing Southline, a 278-mile, high voltage transmission line that will connect the electrical transmission systems of the El Paso and Tucson metropolitan areas.
Building America's Next-Generation Infrastructure to Power Our Future.
Black Forest Partners and Grid United are co-developing Southline Transmission Project.
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Southline Transmission, LLC. invites the public to participate at a public hearing before the Arizona Power Plant and Transmission Line Siting Committee (Committee). Southline Transmission, LLC. is submitting an Application to amend the Certificate of Environmental Compatibility (CEC) granted by the Commitee in Line Siting Case No.173 (CEC 173) to obtain a CEC for the Apache to Vail Upgrade Route of the Southline Transmission Project.
January 12, 2026 | 1:00 PM – 5:30 PM
January 13 – 16, 2026, as needed | 9:00 AM – 5:00 PM
DoubleTree by Hilton Tuscon -Reid Park
445 South Alvernon Way, Tucson, AZ, 85711