The opening of an old cast-iron pipe released a cloud smelling strongly of natural gas Friday, making about 30 people ill and causing the evacuation of nearby buildings.
Workers replacing underground natural gas lines on Tiffany Avenue between Duncan and 29th streets opened the 100-year-old cast-iron pipe at about 10 a.m. Friday to discover that it was filled with gas-scented water, which spilled out into the trench, PG&E spokeswoman Melissa Mooney said.
The smelly spill occurred just upwind of several buildings associated with St. Luke’s Hospital, and the prevailing wind blew the odor directly into the ventilation systems of the two medical office buildings.
Sutter Health spokesman Kevin McCormack said the hospital opted to evacuate a clinic for pregnant women at 1640 Valencia St. and two floors of a general medical office building at 1580 Valencia St.
Natural gas has no smell, but is infused with a foul odor to make leaks detectable. “An odorant that is added to gas had gotten absorbed in the water,” Mooney said, but she said any gas in the pipe had dissipated long ago. She added that crews filled the waterlogged hole with sand, which blocked the odor until the water dissipated.
About 30 people reported feeling sick from the smell, with symptoms ranging from headaches to severe nausea and vomiting, McCormack said. Of those, 10 were admitted to the emergency room at St. Luke’s and one was taken to San Francisco General Hospital.
The clinic at 1640 Valencia St. was closed for the day. The office building at 1580 Valencia was reopened, but many offices had signs saying they were closed Friday afternoon.
“We’re very, very sorry that people experienced discomfort by this and that people in the neighborhood and the hospital were inconvenienced by this,” Mooney said.
Residents of Tiffany Avenue reported smelling the odor Friday, but did not say they got sick. Instead, several expressed relief that there was not an actual gas leak.
“When I smelled it, I was obviously a little concerned,” David McKeown said. But he said the smell disappeared after about 15 minutes.
Neighbor Pam Remy said she was going to clean her garage in anticipation of a garage sale when, “it smelled like gas.” She said the smell dissipated quickly outside but, “when I opened up the garage it smelled strongly.”
She said PG&E workers advised her to air out her house. She was not nervous, she said, because, “all the guys were standing around. They didn’t look like they were trying to get away.”