APS, the local power company, is proposing the construction of a very high voltage power line to be built through the Yuma area. According to information on the APS website, "The proposed North Gila to TS-8 230kV Transmission Project will include power lines approximately 15 miles in length and will be constructed on steel monopoles, typically 130 to 150 feet high. The project will originate at the existing North Gila Substation located near Avenue 8E and County 6th Street and will terminate at a new TS-8 Substation."
The APS website http://www.aps.com/files/siting/Oct_Open_House_Boards.pdf mentions that "High voltage transmission lines have been known to cause interference with radio and television transmissions. Calculated values for this project show some interference to AM radio stations may occur within 200 feet of the line. However, interference to FM radio, digital, satellite, or cable communications is not expected." (see page 27 of that 29-page document).
A map of the proposed route for the transmission line and what the towers will look like (complements of APS) appear below. Yuma area hams may want to keep abreast of this proposed project. There may be issues with RFI on the ham bands.