- It costs four to seven times more to install underground lines than above ground lines. Cost varies depending on the location.
- While underground lines may ultimately experience fewer outages, the average outage lasts much longer. And extended outages are bad news at 40° F below.
One reason underground lines cost more is we install double feeds. That way, if we lose one feed, we’ve got a backup. But sometimes both feeds fail. And unlike many above ground outages that last just seconds – say a tree bounces on a line on its way to the ground – underground outages are rarely temporary. Why? It takes time to dig up frozen ground. And since buried lines are not visible, it also takes time to locate the failure.
GVEA has more than 3,100 miles of power line. Transmission line accounts for approximately 460 miles; distribution line makes up the remaining 2,640. Only 115 miles, or four percent, of our distribution line is underground.
The bottom line: Our co-op tries not to bury power lines. However, if requested by a contractor, we will install them provided the difference in cost is covered by the contractor.