QUESTION: We really appreciate all the hours the linemen have put in everywhere across town, and how far so many of them have traveled (after the storm that hit Longview a week ago). Has SWEPCO considered putting in underground utilities across Longview? It seems it would alleviate a lot of these big outages.
ANSWER: That’s an endeavor that would come with a pretty big price tag.
I asked SWEPCO spokeswoman Carey Sullivan about this and she pointed to a 2012 report from the nonprofit industry group Electric Power Research Institute. That report, she said, estimated it would cost between $5 million and $15 million per mile in urban areas to bury power lines. (Across three states it serves, SWEPCO has more than 26,000 miles of power lines to homes and businesses.)
She said there also are other reasons not to bury power lines.
“If you’re talking about overhead power lines, we have people and trucks who go out and patrol the lines,” she said, who can quickly determined the cause of a power outage — a tree on a line, broken pole or piece of equipment struck by lightening, for instance. “We can do a visual inspection and figure that out very quickly.”
An outage that occurs somewhere underground takes longer to restore, she said.
Also, she said underground power lines are not immune to storm troubles. Even if power lines are underground in one location, they’re above ground somewhere — making the underground lines susceptible to outages.
“This was a major storm with straight line winds,” Sullivan said. “It wasn’t a typical spring thunderstorm. We’re always trying to balance how do you keep the system reliable and spending the right amount of money.
“We’ve been storm-hardening the system for quite a long time,” she added, with bigger, taller poles and rebuilding an aging power grid. That work has been ongoing in about the past decade.
“I know it’s frustrating, really frustrating to lose your power for days,” Sullivan said.
Q: Was it straight-line winds or a tornado that hit Longview Wednesday afternoon? My opinion is that it felt like and it looks like tornado damage.
A: The National Weather Service has said straight-line winds, so I asked Mario Valverde, meteorologist in charge with the National Weather Service in Shreveport, to explain how the agency determined that.
He started with the statement that high winds, regardless whether they’re from tornadoes or straight-line winds, will cause some of the same types of damage. The difference is in the pattern of that damage, which is why the National Weather Service visually inspects storm damage to make a determination.
Valverde explained that tornadoes cause a “convergent damage pattern.” That means the damage that occurs on either side of the tornado will point toward the middle, or toward the tornado.
As for straight-line winds, the damage occurs “along the motion of the storm” — east if the storm is moving west to east, for instance.
People sometimes argue they see twisting in trees that point toward a tornado. He explained, however, that the wind might be pushing a tree more on one side than the other, and trees aren’t perfectly symmetrical.
That “may cause the tree to twist as it falls,” he said.
“You have to look at the overall pattern of damage to make an assessment of what was going on,” Valverde said.
People can even see circulation in the sky with turbulent winds and there not be a tornado. (The definition of a tornado requires that it reaches the ground.)
In the end, though, the damage in Longview was sporadic and pointed east, Valverde said. (There was some “odd things” in the damage that didn’t follow that, but he said that’s not unusual.)
Q: The article on the front page of Wednesday’s paper on the storm did not say how fast the straight-line winds were.
A: The National Weather Service’s full report estimated a peak wind of 90 mph.