Thousands of people across San Leandro had their last night abruptly shut down when metallic, or mylar, balloons drifted into overhead electrical equipment and triggered a major power outage. Pacific Gas and Electric Co. crews spent the evening tracking down the trouble spot, fixing damaged lines, and slowly bringing neighborhoods back online. The blackout started around 5:20 p.m. and dragged into the night, with some residents still waiting for the lights to come back on in the early hours of Sunday. All of it came from what amounted to one runaway party favor with outsized power to knock a neighborhood off the grid.
According to the San Francisco Chronicle, PG&E said the outage initially cut power to more than 5,300 customers. By 7:27 PM, crews had restored electricity to nearly 1,900 of them, leaving roughly 3,500 customers still in the dark. The utility told the paper it traced the disruption to metallic balloons contacting equipment and estimated that full restoration would wrap up around 4 a.m. Sunday. The figures fall squarely within the range of balloon-related outages the region has seen in recent years.
How metallic balloons short out equipment
Utilities say the shiny metallic coating on mylar balloons conducts electricity, so when one hits a power line or transformer it can create an electrical arc that shorts out equipment and can even melt wiring. In a 2025 safety release, PG&E reported that balloon strikes have already caused dozens of outages this year: more than 130 incidents in the first five months of 2025 alone disrupted service to over 54,000 customers. The utility urged people to keep metallic balloons tied down, noting that crews often have to work around energized equipment to make repairs, which adds time and risk to the restoration process.
In a look at earlier incidents, the San Francisco Chronicle reported that a 2020 balloon strike cut power to roughly 7,600 customers, and the company logged 94 balloon-related outages affecting more than 44,000 customers in just the first four months of that year. The paper also highlighted an October incident that cut service to thousands in parts of Oakland, underscoring how often this kind of mishap resurfaces around the Bay Area.
Local utilities renew the warning
Alameda Municipal Power reiterates on its safety page that “Mylar balloons cause power outage incidents in Alameda every year” and advises residents to keep balloons indoors or securely weighted. The agency also warns people never to try to retrieve a balloon from power lines and to report any downed or sparking wires to emergency services or the utility instead.
What to do if you see a balloon on a line
PG&E’s recommendations line up with that guidance: secure metallic balloons with a weight, puncture them and throw them away after use so they cannot float off, and never attempt to remove anything that has become tangled in a power line, according to PG&E. The utility asks customers to report such problems to 1-800-743-5000 and to call 911 if a line is sparking or down, stressing that only trained crews should handle removal or repairs…