Sinkhole opens under Chefornak home, forcing family to evacuate

An Alaskan Native fmily inside a house
Delores Abraham and her family in their Chefornak home that had to be evacuated. (Kimberly Abraham)

The COVID-19 pandemic has not stopped environmental threats in the Y-K Delta.

In Chefornak, a family was forced to evacuate their home after a sinkhole — caused by thawing permafrost — formed beneath it.

Delores “Dolly” Abraham said she and her family had to quickly move into a building in the village intended to be a COVID-19 quarantine facility. 

She said her original fear was not a sinkhole, but the river. By last spring, she said, the riverbank, which is eroding in Chefornak, had almost reached the edge of her home.

“Probably like 6 or less feet,” she said.

With help from the village, Abraham planned to move her home to a safer location. But when contractors came to start the process, they found a bigger problem than the river: There was a 4-6 foot deep sinkhole underneath the house. 

“I got scared. I didn’t want to live in there anymore,” Abraham said. “And the house, when we went in the house it shook a little.”

Because of the unstable foundation, contractors told Abraham her home could not be moved and had to be condemned.

This is not the first sinkhole to appear in Chefornak in recent years.

Mayor Anna Abraham said a few years ago, a man actually fell into a mud-filled sinkhole while walking with his 2-year-old daughter.

“He fell above his waist area, and he wasn’t able to feel anything underneath,” she said.

The man put his daughter on his shoulders, yelled for help, and was assisted out of the hole by neighbors.

Permafrost is thawing in communities all around the Y-K Delta and Alaska, but Chefornak’s situation with sinkholes is a little unique.

Torsten Mayrberger, who is a geotechnical and Arctic engineer, said you can trace the sinkholes back to a volcano 4 miles south of Chefornak that was active long ago.

“If you go into Chefornak itself, there’s boulders everywhere,” Mayrberger said. “Those boulders are from the volcanic eruption.”

Mayrberger works for PND Engineers, which is partnering with the Alaska Native Tribal Health Consortium to help Chefornak with environmental threats. He said the volcanic boulders make up a lot of the permafrost in Chefornak. In between the boulders is silt or mud. When the icy silt between the boulders melts, it can create pockets of unstable ground people call sinkholes.

Although, Mayrberger said, it’s not very accurate to describe them as holes.

“It’s not a hole at all. It’s just soft soil that’s not draining,” he said. “It’s just mud. It’s like the quicksand that you see in the old movies.”

Climate change is a big reason why the permafrost is melting. Last year was the second warmest year on record, according to the National Oceanic and Atmospheric Administration.

But climate change isn’t the only reason for the permafrost thaw, according to Don Antrobus, the Climate Change Adaptation Program Manager at ANTHC.

“What we’re seeing right now is some dramatic change in the permafrost in communities that is exceeding the rates that are estimated by our climate science,” Antrobus said. “So I don’t think that means that climate science is wrong. I think that means there are other drivers.”

Antrobus said contributing factors could be foot traffic, heat radiating from buildings, or even how water drains in some communities. 

“I think it’s important to really evaluate that and determine what the drivers are,” he said. “If we assume it’s simply climate change, and we move to a new location and we repeat our same building practices, then we’re likely to see the same results.”

Mayrberger, the geotechnical engineer, agrees with Antrobus. He’s helping Chefornak plan a new subdivision to replace some of the buildings threatened by permafrost degradation, erosion, and flooding. One of Mayrberger’s ideas to avoid those problems in the future is to build 10-unit townhouses so there are fewer structures emitting heat into the permafrost. 

“The smaller footprint of your urbanized area, the better,” Mayrberger said.

But while longer-term plans are in progress, there are emergencies already at hand.

When the sinkhole was discovered under Abraham’s home, her family became homeless. They bounced around with other family members until moving in with Abraham’s son.  

Six months after the family’s evacuation, the city finished remodeling its community center building with CARES Act funding. It was intended as a quarantine center.

Mayor Anna Abraham said offering the residence to Dolly Abraham’s family still served the purpose of funding.

“Due to the overcrowding of one residential home, trying to limit the exposure of COVID to spread in our community, we decided to put her in there,” said the mayor.

Dolly Abraham said she’s thankful for her temporary residence, but she’s hoping to be back in a home that’s hers. She’s applied for a federal grant that could build her a new house by 2023.