A California house was on the market. A 6.4 earthquake left it red-tagged

After moving to Rio Dell, Calif., about a year ago, Gage Allen Dupper found a quaint house to share with a married couple.

Dupper said the pair were in the process of selling the two-bedroom, one-bath home when a magnitude 6.4 earthquake rattled Northern California in the pre-dawn hours Tuesday, striking offshore about 7½ miles southwest of nearby Ferndale.

“We had it online. We had Realtors helping people walk through it and trying to sell the house,” said Dupper, 24. “And it happened to be at such a perfect time that we were nearly with an offer letter — and then everything fell apart.”

When he was jolted awake by the 2:34 a.m. quake, Dupper said, he assumed the shaking was just another mild temblor in an area known for them.

“We have them frequently, but when we woke up and we decided we needed to leave the building, we walked out our front door and our porch was two feet higher than it normally was,” he said. “We realized our entire foundation was completely gone.”

Dupper said the owners were too distraught to speak with The Times, and efforts to reach them were not successful.

He said the house suffered gas and water leaks, and the entire street was evacuated for several hours. The earthquake knocked out power for tens of thousands of people in Humboldt County and left residents of Rio Dell without any water. Dupper said he left the house with only the clothes on his back, his wallet and his phone.

He later was notified the house had been red-tagged.

A sign declares a home unsafe after an earthquake.

(Andrea Wrisley)

“The house is completely condemned,” he said. “It’s uninhabitable due to ruptured pipes and the foundation being off — it’s not a safe place. The police said you need to leave and go across the bridge, or else there could be consequences. It’s a very scary thing.”

Dupper, who works at an assisted living facility, went to work around 3 a.m. and has been there since. He said he plans to spend the night in the activities room until he can figure out long-term plans for lodging.

Cindy Pridmore, a geologist with the California Geological Survey, warned about the dangers of living in unstable or weakened structures following an earthquake.

The earthquake, which resulted in the deaths of at least two people and injured 11, was followed by at least 80 aftershocks, with three registering 3.9 or greater, Pridmore said.

There’s a 13% chance of a magnitude 5 or greater earthquake after the initial shaker, according to U.S. Geological Survey’s earthquake forecast, but that could change, Pridmore said.

“People do need to be prepared, especially if they’re in weakened structures, to be mindful of where they’re staying,” she said.

Rio Dell Mayor Debra Garnes told The Times that building inspectors were moving through the city to check on the structural integrity of homes and other buildings.

As many as 150 residents are expected to be displaced by the quake and will be sheltered at Monument Middle School, if the building is deemed structurally sound, city officials said. Otherwise, they’ll be housed at the Fire Hall.

“Our biggest issues are no electricity and no water. Structural damage is the next thing on the list,” Garnes said. “Our water system got really wrecked. So many leaks.”

Andrea Wrisley, 34, Dupper’s neighbor, also was evacuated because of a gas leak, but her house’s foundation came through with only a few cracks. Wrisley and her family were allowed back inside.

A lifelong Humboldt County resident, Wrisley said she’s grown accustomed to earthquakes over the years, although she acknowledged it can be jarring for new residents.

“This definitely has been the most serious one we’ve had in quite some time,” she said. “Most of the time, we have tiny shakers and we’ll maybe lose a plate or a cup or something. This is definitely going to be intimidating to those who are less familiar with earthquakes.”

Dupper, who’s lived in Chico and Puerto Rico in the past, said he hopes to stay in Rio Dell, but this experience has rattled him.

“If this is a consistent pattern and I can see that, I don’t know if I can [stay], not with the damage that’s been dealt,” he said. “I would like to stay here, but that’s not exactly a guarantee.”