As an east coast / gulf coast navy brat and Coastie I've had too many hurricanes come through and take out power to look at. We had a neighborhhod across the street from the power plant that had no power for two weeks while they brought everyone else back on-line within a few days. I kept expecting to see extension chords stretched across the road!

They can (and do!) bury power lines in some regions of the country. Part of the problem is shielding and the other is heat generated by resistance in the lines. The largest problem by far is that either the conduits have to be man sized to facilitate repairs or thay have to have disconnects and man vaults to gather the faulty line they are replacing into. Due to high water tables in most areas these are constantly flooding causing more problems.

If you have permafrost in the area it would probably just cause more problems than it would solve.