By Esther Nguonly and Hallie Falquet
WASHINGTON – Power outages caused by fallen trees and branches should not be of the magnitude of some past storm events, even with a major winter storm expected to encase the region in up to three-fourths of an inch of ice, experts say.
However, even the healthiest trees face damage and taller trees may fall, imperiling lines, people and property, if the weather forecasts are correct, said Kevin Mullinary, a certified arborist and Maryland licensed tree expert.
Up to three-fourths of an inch of ice is expected during a period of freezing rain between 8 p.m. and 10 p.m. Tuesday, said John Darnley, observation program leader at the National Weather Service.
“If it’s as bad as they say it’s going to be, a lot of people are going to wake up late because their alarm clocks are not going to be going off,” said Mullinary.
“At a quarter of an inch, power lines are OK,” Darnley said, “but half, three-quarters of an inch and you get a problem with trees.”
He predicts the freezing drizzle to end by 10 a.m. Wednesday, but due to colder temperatures, the icy tree limbs will stay frozen through Thursday night.
Outages have sparked outrage during past storm events and utility companies have put the blame on the region’s heavy tree canopy. Among the most notable incidents were Hurricane Isabel in 2003 and a January ice storm in 1999.
Strong winds and rain from Hurricane Isabel in 2003 directly resulted in 16 deaths in seven states and $410 million worth of insured property damage in Maryland as of December 2003, according to a report from the National Hurricane Center. With other damage included, that figure doubles to about $820 million.
Of those deaths, seven were caused by fallen trees and branches, reported the National Weather Service.
Studies show that 50 mph or higher winds will cause damage to even the strongest trees, Mullinary said.
“If what they’re saying does happen,” said Mullinary, “I’m not going to envy (the power companies).”
Power companies such as Pepco and Baltimore Gas & Electric have set up routine tree-trimming and maintenance to ensure that nearby areas are protected from power outages resulting from fallen limbs and trees.
“On any given day there are likely to be multiple tree-trimming efforts,” said Linda Foy, spokeswoman for BGE.
The company services 1.25 million customers in the greater Baltimore and Annapolis areas, and in Foy’s estimate, about 2 million trees.
“We have a regular maintenance schedule that spells out how and when we would trim trees,” Foy said.
Pepco has identified “problem areas” and provided safety measures such as electric wires with insulated “tree wire” to harden the lines for better protection.
“Even though the utility companies are doing their best, there are still tall trees with limbs over wire,” which may lead to lots of short-circuiting, said Mullinary.
Many residents had opposed cutting trees in their neighborhoods and in the suburbs, either for environmental or aesthetic reasons in the past, said Mullinary.
“Most suburbs are very heavily forested. That’s the beauty of them. But trees and power outages can be a problem,” said Robert Dobkin, a spokesman for Pepco.
The Baltimore-Washington Corridor is the most heavily forested quarter on the East Coast, and trees are the single most dangerous threat to power outages, said Dobkin.
In addition to the year-round tree trimming schedule, BGE also holds storm drills several times a year where it simulates a winter storm. In the case of the upcoming ice storm, Foy said confidently, “We are planned for it and prepared for it.”
Power companies in the area are more prepared than before to handle such emergencies, especially since the last hurricanes, Mullinary said.
“I am a tree-hugger in capital letters,” said Mullinary. “But trees and power lines don’t co-exist. We have to cut back.”