Dominion is burying power lines to reduce threat of outages

Dominion wants to bury these power lines on Brenda Lane, Annandale.

Dominion Virginia Power plans to bury approximately 4,000 miles of power lines – including 1,000 in Northern Virginia – over the next 10 years in an effort to reduce power outages.

A letter sent to a resident of Brenda Lane in the Columbia Pines neighborhood in Annandale earlier this month says: “Dominion is identifying overhead lines that are most vulnerable to power outages during storm events . . . To improve the quality of your electric service and minimize service interruptions, we would like to remove the existing overhead line on [your] property and replace it with an underground line at no cost to you.”

A Dominion representative will meet with affected residents to describe the process and schedule and to discuss any easements that might be necessary, the letter says. If the project is deemed feasible, construction could start after Feb. 15, 2015, but not before the easements are obtained. 

The company says it’s using a data-driven process to analyze 10 years of outage information to determine which overhead tap lines are most vulnerable during storms. Tap lines are the overhead wires that go into neighborhoods and typically sustain the most damage during storms due to trees falling on them.

The derecho storm in 2012 affected a million Dominion customers, says Alan Bradshaw, underground program director for Dominion Virginia Power. By burying 20 percent of the tap lines, the company can reduce the number of repair locations by 50 percent, he says.

Dominion’s Strategic Underground Program began in July and will continue to develop throughout 2015, leading to a full rollout in 2016, says Sue Holcroft, electric distribution underground marketing and communications coordinator.

Tap lines bring power to neighborhood streets. [Dominion Virginia Power]

The cost of the project is estimated at $175 million a year for 10 years.

Legislation enacted earlier this year allows electrical utility lines to cover the costs associated with replacing overhead power lines with underground lines. Funding will come from a special rate adjustment called a rider, which must be approved by the State Corporation Commission.

Dominion says it will request a “small, gradual” rate increase over time to cover the costs of the program. The rate increase will be reflected on the monthly bills of all Dominion residential and small commercial customers, including those who are not targeted for the underground program and those who already have underground lines.

According to Dominion, all customers will benefit from the program because it will “improve reliability of the system and shorten the time for restoring service to all affected customers following a major storm.”

In most cases, Dominion will use “low-impact directional boring technology” to bury power lines, rather than digging trenches. All property owners along a tap line would have to agree before the work could be carried out.

According to Holcroft, Dominion hopes to partner with telephone and cable companies to explore whether they are interested in having their lines moved underground at the same time as the electrical lines. If they don’t want to move their lines underground, utility poles will stay in place.

“Undergrounding is not a cure-all for power outages,” Holcroft says. “During a major storm, large numbers of customers may still be affected because most underground electric service connects to overhead lines and equipment that are still vulnerable to weather, trees, animals, and vehicle accidents.” Strategically burying certain lines, however, should reduce the frequency and duration of outages.