Why aren't more power lines buried?

[UncleFred]

My small neighborhood has all utilities underground. The insulation on the 50+ year old service to my house ‘wore out’ and ruptured while some adjacent work was being done. They replaced it with new wires, and this time used a conduit.

An occasional bigger problem was our telephone service would get messed up during periods of heavy rain. Apparently some of the (bigger) junction cabinets were old and leaky. It doesn’t help that we live in a low-lying area with a high water table.

[elmwood]

@Hari_Seldon

How is it that a much poorer society was able to do these things a century ago and they cannot do them today?

Part of it is labor cost. In the Northeast, at least, construction workers get paid a fairly decent wage, and those working on tunnel, bridge and high rise projects (sandhogs and iron workers) earn upper middle class salaries. In olden times, construction labor was cheap, even adjusted for inflation. There was no shortage of off-the-boat immigrants willing to risk their lives for a few cents a day to put food on the table.

[Jophiel]

@Q.E.D

No, they don’t although, yes, they usually do. There are above-ground natural gas pipelines which run on pylons, but they are not common, for safety reasons. The lines themselves are perfectly safe; even lightning isn’t generally an issue unless the pipe is leaking–the metal walls simply conduct the bolt straight to ground through the pylons. The real problem is they’re vulnerable to sabotage and vandalism, as well as vehicular accidents.

Speaking of which, hitting a gas line has more potential to be catastrophic than hitting an electric line. While they don’t have to bury the gas line, there’s a very good incentive to do so. They also bury them deep – seven feet or more around here (at least according to the utilities locaters I speak with).

[Sleel]

@Spectre_of_Pithecanthropus

Around these parts, where the border between L.A. and Beverly Hills is often in the middle of a quiet residential street otherwise the same on either side–the Los Angeles side has utility poles and the Beverly Hills side does not.

Presumably, in California, earthquakes are another consideration.

Buried lines are probably safer than above-ground power lines. If you build with enough flexibility in the system, most of the lines will remain intact, and those that do break will not be dangerous. Power lines on poles come down with some regularity in an earthquake, though, and are one of the things earthquake safety manuals mention as a post-quake hazard.

[robby]

Related article here:
Why Can’t We Just Bury Powerlines?

Some factoids from the article:

…Putting lines underground would cost about $1 million a mile – 10 times the cost of overhead lines, according to an Edison Electric study.

…In the 13 years prior [to] a 2006 study by the Edison Electric Institute, about half of all capital expenditures by U.S. investor-owned utilities for new transmission and distribution wires have been for underground wires. Still, about 70% of the nation’s distribution system has been built with overhead lines.

Research has shown that there are fewer outages in areas where there are underground lines, and underground lines can make sense in new residential areas or densely populated areas such as New York City.

But when outages do occur, they tend to last longer because finding and fixing the problem is more difficult.

[Great_Dave]

Eventually, this will all be moot, once we get our Mr. Fusions (or all convert to local generation by various means).