Months after storms knocked out power for several days at a time in Northbrook, ComEd officials presented the village board of trustees with a plan for $2 million in improvements.
Following , President Sandra Frum asked ComEd to investigate and improve reliability in Northbrook, particularly in the central business district. During one storm in June parts of downtown—including and the —remained without power for more than three days. That week, the grocery store had to throw out several dumpsters worth of food.
“We feel that the response by Commonwealth Edison was not appropriate, was not satisfactory,” she told ComEd representatives at a July 1 village board meeting.
At Tuesday night’s meeting, representatives from ComEd acknowledged that Northbrook has an ongoing problem with outages caused by falling tree branches.
“The central business district was crippled by the summer outages,” said Eric Duray, external affairs manager for the utility. In response to Frum’s request for a plan to improve reliability, he promised that the agency would make several upgrades to address the problem.
To make the power lines more resilient downtown, ComEd will install new, covered wires on several streets near downtown Northbrook, including Keystone, Thornwood, Redwood and Milton lanes. Unlike traditional power lines, where three cables are spread out atop an eight-foot cross-arm, the new lines will be grouped in a tighter formation on the side of the utility poles. Because the lines are stronger and grouped more closely, they are more resistant to power outages caused by falling tree branches, Duray explained.
“When we see excessive repeat outages such as these, this is an ideal tool,” he said. Other companies that have used the cable have seen a 75 to 80 percent reduction in power outages caused by vegetation, according to Duray.
ComEd will also reconfigure the switches around downtown Northbrook so that the utility can quickly and remotely replace one power source with another in the event of an outage.
In the Ancient Tree subdivision, where tree branches caused total power outages this summer, ComEd is also planning to conduct additional tree trimming and will switch some customers in the area to a different, more reliable transformer.
Altogether, Duray estimated that the improvements would cost $2 to $2.5 million. In comparison, the utility spends $500,000 to $1 million in an average year on maintenance in Northbrook.
The installation of new cables near downtown and trimming in the Ancient Tree subdivision should be completed by March 2012, according to Duray, while the circuits will be reconfigured downtown by May 2012.
He predicted that the projects would improve electric reliability for 2,000 to 4,000 customers directly impacted by the transformers involved, and for at least an additional 4,000 customers who will now have better backup should their own transformers go out.
Village officials were pleased with the financial commitment ComEd was making, but were concerned that the timeframe might be unrealistic.
According to Duray, ComEd will hire outside contractors to help trim trees in the Ancient Tree subdivision and around downtown Northbrook.
“We intend to meet these milestones,” he said.