CenterPoint and the trees

Among the many questions being asked post-Ike are those about whether CenterPoint met its requirements for maintaining trees near power lines.

Hugh Rice Kelly, a former chairman of Trees for Houston and former general counsel for CenterPoint's predecessor, Houston Light & Power, has long criticized the company as overzealous in trimming along transmission and distribution lines. He said workers sometimes damage trees or remove ones that don't threaten pole-top power lines.

But whether the utility cuts too much or too little doesn't have much to do with the lingering outages, Kelly said.

"The trees that really damaged the lines were big trees that, for the most part, were well beyond the reach of CenterPoint tree trimmers," said Kelly. "Unless you gave them the authority to cut things beyond that, there's not much more they could have done."

CenterPoint budgets about $21 million per year for tree trimming along power lines, with about $18 million set aside for distribution lines like those that run behind businesses or in backyards, said Terry Finley, CenterPoint's vice president of distribution engineering and services.

The company sets a goal of trimming trees back from lines every four years for 12 kilovolt lines and every three years for 35 kilovolt lines, both of which can run through residential neighborhoods.

That means the company's contract tree trimmers cover about 9,000 miles of distribution lines per year.

But those three- and four-year cycles are only goals and are not mandated by federal, state or local laws, according to industry officials.

There's evidence that CenterPoint hasn't done as much as it should have in this department. Having said that, I tend to agree with Kelly in saying that that's not necessarily a bad thing. I don't think that more trimming would have lessened the impact of Ike that much, but I do think it would have been less than optimal for the trees themselves. Having a lot of trees in Houston is generally a good thing. I don't want them to be thought of as a nuisance.

CenterPoint tries to warn customers about trees on their property that appear to be potential threats to power lines, but Kelly said it's difficult to identify which trees will go down in a storm.

"Many of those that came down in this storm were very healthy," Kelly said.

And in a hurricane, a branch may fly at 100 mph into a power line hundreds of feet away.

"People just have to be realistic," Kelly said. "We can't have the kind of shade trees we want in Houston and still protect the power lines 100 percent. We'd become the Lubbock of the Gulf Coast if we took that approach."

There is another option, and that's to take steps like burying power lines to make them less vulnerable to trees in a hurricane. That would cost a bunch of money, so it's not a general solution. But it probably does make sense in some areas outside downtown, and there may be some other places where residents would be willing to pay more to make this happen. As I've said before, we should at least have the conversation and see what's feasible. If not now, then when?

And on the power restoration front, CenterPoint is down to 167,000 customers without power, or 7% of their total, down from 247,000 as of 7 AM Sunday and 449,000 on Friday. Big steps forward, though not much consolation if you're in that seven percent.

Spokesman Floyd LeBlanc said CenterPoint missed its goal of completing all repairs to major lines, but expects to finish that work early this week and begin repairs to transformers and lines serving individual customers.

More here. No new target dates at this point.

Posted by Charles Kuffner on September 29, 2008 to Hurricane Katrina