If the voltage of any electric line described in section 75-709 will exceed fifteen thousand volts and such line will be within one-quarter mile of any existing electrical or communication line of any other person or signal line of any railroad or if the voltage of such electric line will exceed seven hundred volts and such line will be within five hundred feet of the electrical or communication line of any other person or signal line of any railroad, application to construct the line shall be made to the commission, except that no application shall be required for any line which will not exceed fifteen thousand volts, which will not exceed six hundred sixty feet in length, and which will be more than seventy-five feet from any existing electrical or communication line of any other person or signal line of any railroad. The projectors of such line shall file with their application (1) a map or drawing showing the route of the proposed line and any existing electrical or communication lines or railroad signal lines within the respective distances described in this section, which drawing shall identify and give the names of the owners of such other lines, (2) specifications showing the manner of the construction of the proposed line, and (3) such other information as the commission may prescribe. Application shall be made to increase the voltage of an existing line in the manner stated for new construction as provided in this section.