Underground high voltage distribution systems cost significantly more to install and maintain, plus in my opinion, more difficult to troubleshoot and/or considered to be more dangerous to work on, and for anyone who digs up earth for any reason. Also, underground high voltage distribution systems have a much shorter lifespan than overhead high voltage distribution systems, plus overhead is much easier to maintain and troubleshoot. There are several different determining factors and considerations that come into play for whatever kind of electrical high voltage system that will be designed/engineered before most any installation. During emergency type situations, much of, if any depending on location, of the national codes and/or rules typically gets tossed out the window until some form of utility power is restored of any mass wide spread outages. Once the dust clears though and most services are restored with stability, usually reengineering takes place for a more permanent solution of whatever power structure system determined by the electrical engineers. It's been years since I was an electrical lineman so, things may have change some, but I couldn't imagine by too much. Perhaps someone else may be more up to date on it than myself though?
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