WASHINGTON (WUSA9) -- An equipment failure is to blame for a region-wide power outage that impacted the White House, the Capitol, the University of Maryland and other buildings throughout D.C. and Maryland on Tuesday afternoon, according to an official.

D.C. Department of Homeland Security and Emergency Management spokeswoman Robyn Johnson told the Associated Press that the outage affected 8,000 customers in the District.

The equipment failure happened at a power switching station in rural Chalres County. The station is owned by Pepco and SMECO. At about 12:30 p.m. one of the ceramic insulators fell to the ground, causing a fire as it hit a 230-thousand volt transmission line during its fall, according to a Pepco spokesperson.

Those near the incident described it sounding like an explosion, but it was actually a very high voltage short, WUSA9's Peggy Fox reported.


Pepco power outage map

Maryland Office of Emergency Management map

Pepco's outage map showed more than 2,400 Pepco customers were without power in D.C. at one point on Tuesday afternoon.

Pepco (@PepcoConnect) tweeted details about the outage around 2 p.m. " Shortly before 1 p.m. we experienced a dip in voltage in the Washington D.C. area. This was caused by an issue with a transmission line," read the first tweet.

Officials added, "There was never a loss of permanent electric supply but dip in voltage caused equipment at some facilities to transfer to backup systems."

They say they are trying to repair the transmission equipment fault in Charles County.

Metro services were impacted by the outages. Stations including Navy Yard, Benning Road and Potomac Avenue ran on backup power for a short time. Power to all Metrorail stations was restored by 2: 45 p.m.

Regan National and Dulles International Airports were not impacted by the outage.

The University of Maryland closed at 2 p.m. because of the power outage. Prince George's County Fire Officials told WUSA9's Bruce Leshan that crews freed about 12 people who were stuck inside elevators on the University's campus.

Power was restored to all areas of the University of Maryland Campus by 5:00 p.m.

Union Station lost power, according to VRE at 1:15 p.m. Trains were held until power was restored. Trains were delayed between 10 and 30 minutes.

The power also reportedly went out while Oprah Winfrey was speaking at the dedication ceremony for the Maya Angelou postage stamp.

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The Smithsonian tweeted that some of its museums were impacted by the outage and that the buildings were evacuated on Tuesday afternoon.

Some of the outages have been brief. Power has been restored to the Capitol grounds.

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