Project Description

WAPA proposes to approve APS’s interconnection request and enter into an interconnection agreement associated with the construction of a new APS transmission line that would interconnect with the Mead-Perkins 525-kV transmission line, which is operated and maintained by WAPA. Section 211 of the Federal Power Act requires that transmission service be provided upon request if capacity is available without impairing the continued reliability of electric systems and if it is in the public interest to do so.

To accommodate the interconnection, WAPA would do the following:

  • Obtain right-of-way (ROW), construct, own, and operate a new 500-kV switchyard, up to 35 acres in size and containing up to four 500-kV breaker bays, located between the Mead-Perkins 525-kV line and APS’s new TS-01 Substation. The MPP-Q01 switchyard would be the Point of Interconnection (POI),
  • Install and maintain a microwave tower adjacent to the existing communication facilities at Pete Smith Peak to maintain WAPA radio communications with the MPP-Q01switchyard, as well as maintain communication with the TS-01 and TS-02 substations that will be constructed, operated, and maintained by APS.
  • Obtain ROW and install and maintain a microwave tower approximately 10 miles southeast of the interconnect location, near Mead-Perkins 525-kV transmission structure169-5. This tower will be used as a relay station between the MPP-Q01 switchyard and the Pete Smith Peak microwave tower to provide microwave communications to the POI.
  • Provide redundant communications to the POI, by using dedicated capacity on an APS-owned and installed Optical Ground Wire (OGW) fiber optic cable along the new transmission line from the POI to APS’s TS-01 substation.

APS’s privately developed facilities would include the following:

  • Construction, operation, and maintenance of a 14-mile long 230-kV transmission line.
  • Construction, operation, and maintenance of an approximately 15-acre substation adjacent to the MPP-Q01 switchyard, to be known as TS-01, which would include up to two 525/230/34.5-kV transformers and associated switch gear.
  • Construction, operation, and maintenance of an approximately 15-acre substation at the north end of the proposed transmission line, to be known as TS-02, which would include up to two 230/115-kV transformers, up to two 230/69-kV transformers, and associated switch gear.
  • Construction, operation, and maintenance of a 14-mile-long fiber optic cable along the new transmission line from TS-01 to APS’s Bagdad Substation via APS’s Willow Lake 115-kV transmission line. WAPA would use dedicated capacity on this cable for redundant communications for the MPP-Q01 switchyard.

Project Location

The MPP-Q01 switchyard, TS-01 substation, 169-5 microwave tower, and majority of the new transmission line would be located on State Trust Land managed by the Arizona State Land Department. The communications tower constructed at Pete Smith Peak would be located within an existing right-of-way on land managed by the Bureau of Land Management (BLM). The northernmost portion of the transmission line and the TS-02 substation would be constructed on private land near Bagdad. Altogether, the project area includes 267 acres of State Trust Land, less than 1-acre of BLM land, and 37-acres of private lands (total of 305-acres).

Current Status

WAPA released the Final Environmental Assessment (EA) and a Finding of No Significant Impact (FONSI) in September 2026.

Project Documents

Contact Information

For questions on the environmental review process please contact:

Abigail Wilmington, Environmental Project Manager
Civil Design & Engineering Inc. (CD&E) on contract to
Western Area Power Administration, Desert Southwest Region
Phone: (480) 790-3282
Email: Wilmington@wapa.gov

Last modified on September 11th, 2026