More than a million people were left powerless in northern Virginia after the Friday thunderstorm on June 29. 34,000 total customers had lost electricity in Alexandria, and 23,000 of those customers still lacked power as of Monday, July 2. The response has made many people ask: How is it decided what neighborhoods get power ahead of others?
First, Dominion Virginia Power had to restore all of the downed transmission lines. As Dominion's media relations officer Le-Ha Anderson described, repairing the nine transmission lines that were downed throughout Virginia were critical to restoring power throughout the state. Following the transmission lines, then the distribution lines and sub-stations needed repair.
"If you think of the electric power grid, the transmission lines are like the highways," said Anderson, "and the distribution lines are like the roads that connect the highways to the neighborhoods."
Secondly, once the transmission lines and the distribution lines are repaired, crew members had to tend to critical infrastructure — buildings that are important to people's health and safety. Each jurisdiction creates and updates its own list of what it considers critical infrastructure, but the list usually includes hospitals, health clinics, 9-1-1 emergency call centers, emergency operation centers, pumping stations and nursing homes.
"The circumstances made it absolutely critical to get the health centers up and running."
— Ashley Ehrhart, Alexandria Fire Department
What is deemed critical infrastructure by a jurisdiction can be circumstantial to the emergency. In Alexandria, city officials placed a high priority on health centers and neighborhoods with vulnerable populations. "The circumstances made it absolutely critical to get the health centers up and running," said Ashley Ehrhart of the Alexandria Fire Department, who included the Flora Krause Casey Clinic, cancer clinics, and dialysis centers as infrastructure that desperately needed power.
Moreover, the subsequent heat exacerbated health concerns. With the lack of power, many were worried about the elderly. Therefore, city officials included nursing homes on the list of critical infrastructure.
Finally, once the critical infrastructure had electricity, Dominion then began to restore electricity to residents. Specifically, Dominion made restoring power to the neighborhoods with the most customers high priority. "If there's a tree that has a fallen line and it affects 480 customers, and there is a similar situation but it affects 10 customers, we will go to the fallen line that affects the 480 customers," said Anderson.
To manage the many crews that must visit several locations each day, each Dominion office had a small team of usually four to five people working overnight. These teams were in charge of "packaging." Packaging is a role that includes gathering all the relevant information, prioritizing what neighborhoods needed attention according to the number of customers, and then creating a list of locations for each crew to visit for the coming day.
These teams, made up of administrators, designers, and other Dominion employees, had been trained to package for emergency situations. Twice a year, Dominion performs a three-day drill to prepare themselves for an emergency. "It's not just internal, but external as well," said Anderson, describing how Dominion has participated in these drills with local emergency response centers.
While for the first few days after the storm Dominion was trying to restore power to the greatest amount of customers, by Wednesday or Thursday, many of these teams shifted their strategies. They went into "sweep mode," which meant that crews no longer jumped from location to location based off the number of customers, but instead worked at a single location and then moved down the next point along the circuit. Although sweep mode is less efficient that tending to the greatest amount of customers possible, it made sure that every single customer gained power by Friday, July 6.
With that said, Dominion worked with local jurisdictions throughout the week to make sure that vulnerable populations were tended to. In Alexandria, this included high rises, nursing homes, and key traffic intersections. "Our priority was to help the areas with the greatest need," said Ehrhart, "they were very receptive to what we needed."
June's storm was highly unusual, said city officials, due in part to the lack of warning. While hurricanes can be powerful and destructive, their impact are usually tempered by the fact that city and Dominion officials can prepare for it. Derecho, on the other hand, caught many by surprise.
"We can't activate full city emergency every time there's a thunderstorm that's coming," said Ehrhart, "instead we have to wait and see what happens."
All in all, Dominion worked a total 11,050 locations last week, which included everything from transmission lines to sub-stations to tap lines that connect to single households, in order restore electricity to over 540,000 customers. By Thursday, 95 percent of all affected customers had restored power, and 876 customers in Alexandria were without power.