From the FAA's Chart Users' Guide:
AeroNav Products’ charts are prepared in accordance with
specifications of the Interagency Air Cartographic Committee (IACC)
and are approved by representatives of the Federal Aviation
Administration (FAA) and the Department of Defense (DoD).
Book 2 of the IACC Specifications covers Sectionals and VFR Terminal Charts and provides the following guidance for transmission lines:
18.104.22.168 Telecommunication and Power Transmission Lines (T-Lines)
22.214.171.124.1 Landmark Value
T-Lines, if depicted on charts, are shown primarily for their landmark
value. Determination of whether a T-line has landmark value or what
constitutes chart congestion are matters of FAA Flight Edit judgment.
Flight Edit shall either delete or add T-Lines on the Flight Edit
Standard. T-lines with landmark value should be shown in open country
and not in congested or built-up areas. Through open country, T-lines
should be shown as continuous lines, interrupted only for reasons of
cartographic practices. Location of the pylon symbol is dependent
upon the length of the T-line; approximately at 1" intervals on a line
3" or less in length, and approximately 2" apart on lines longer than
The transmission lines may also be charted under the rules of section 126.96.36.199 Obstructions.
So, no. T-Lines are not charted exhaustively. They are charted only when they have landmark value or are charted as an obstruction.