The answer isn’t that simple. Certainly, having high powered transmission lines below dirt would significantly reduce the number of ignitions from downed lines, but some experts say the transition and maintenance of ‘Undergrounding’ may be cost prohibitive.
Both PG&E and SoCal Edison can bury transmission lines but it’s not something either utility says it’s willing to do on its own. But, let’s say you and your neighbors wanted the power lines in your community buried; the utilities would do it…and, send you the bill.
PG&E had once said the cost of Undergrounding a transmission line would run about $3 million per mile, up to $5 million in urban areas – that’s compared to the price tag of $800,000 per mile to suspend the lines. In 2017, PG&E said it had 81,000 lines. If all those lines were buried it could cost in excess of $200 Billion and take up to 1,000 years to finish.
CalFire has declared the city of Malibu a Very High Fire Hazard Severity Zone. The city had at one time been exploring undergrounding with SoCal Edison. The estimated price tag would have been around $200 million.
In addition to the high cost of construction, experts say maintenance is a challenge. When a suspended power line fails, it’s pretty easy to find the spot and repair it – causing a 24-48 hour outage, whereas an underground line failure is difficult to track down and because crews may have to dig down to the line an outage could last up to 3 weeks.
PG&E says just because a power line is underground doesn’t mean it’s not vulnerable to damage. The utility says underground lines can be damaged by flooding, earthquakes and accidental breakage by a 3rd party construction crew.
Both PG&E and SoCal Edison say they’re not opposed to exploring the future of undergrounding, but they caution that it has to be the right fit for a community and/or region and the costs have to be absorbed by the requesting entity.
For more information on undergounding read this fact sheet from PG&E here
Also, read the latest study done by the non-partisan Edison Electric Institute here
You can also listen to my feature from Wake-Up Call:
Photos: PG&E