Metallic balloons trigger widespread power outage in East Bay

Metallic balloons triggered a widespread power outage in the San Leandro area, leaving more than 3,000 customers without power Saturday evening as the temperature dipped into the mid-40s.

The outage began at 5:20 p.m., initially plunging more than 5,300 customers into darkness, said Edgar Hopida, a Pacific Gas and Electric Co. spokesperson. By 7:27 p.m., staff restored power to nearly 1,900 customers, leaving about 3,500 still without power. PG&E estimated restoration time would be 4 a.m. Sunday.

Metallic balloons, also known as mylar balloons, have a silvery coating that conducts electricity, which can short transformers and melt electric wires when they come into contact with utility equipment, PG&E spokesperson Jennifer Robinson previously told the Chronicle. 

In 2020, one of these balloons caused 7,600 customers in San Francisco’s North Beach and Russian Hill neighborhoods to lose power. In the first four months of that year, utility officials said metallic balloons caused 94 PG&E power outages affecting more than 44,000 homes and businesses.

In October, a metallic balloon contributed to thousands of Oakland residents losing power. Alameda Municipal Power warns those handling the shiny, helium-filled balloons to be mindful around power lines. 

“Mylar balloons cause power outage incidents in Alameda every year,” the department said. “When released, these metallic, helium-filled balloons can touch high-voltage lines, resulting in explosions and outages.”