Sink hole forming? Land leaking some kind of gas?

Observation by Cynthia Paniyak

A concerned citizen, of Chevak, came to our tribe to let us know of a ground leak of something like gas. As we went to check, we observed a puddle of water with some kind of sludge around it. We can see bubbles coming from the bottom of the puddle. This bottom of the puddle seemed to be getting deeper, as the concerned citizen noticed. He also stated that he noticed it throughout the year, even through the winter/spring. This area is within the village and is right next to the well used roadway. We want to know what we can do to find out what it is and if it is going to get worse than how it is now. (location:165°35'15" W 61°31'43" N)

LEO Says

Thank you Cynthia for this fascinating and well document observation. Additional investigation would be needed to confirm what is actually occurring here. One way is to photograph the site from the same location periodically to monitor any changes in size or depth. It would be helpful to document whether the flow changes over time. It would also be interesting to learn if there are any odors associated with the bubbles. Please see the insightful comments by Dana Brunswick (ANTHC) and Katie Walter Anthony (UAF) below. Lars Flora

Note: an additional video was provided after the initial consults by Dana and Katey. The observer also provided a link in the sidebar for Google earth location and video of the bubbles.

Comment by Dana Brunswick

Here are some theories on what could be behind this phenomena:

1. Permafrost thaw creating a groundwater pathway. As ice-rich permafrost degrades, the frozen layer that historically acted as an aquitard (impermeable barrier) becomes discontinuous. Groundwater that was previously trapped below the permafrost can then move upward through thawed zones (taliks) like an artisanal aquifer or spring.
2. Waterline leak. If there is continuous flow regardless of rainfall and temperatures it could be from a nearby pipe.
3. Bubbles could be gas that is produced from decomposing organics. They could also be from trapped air in pipes.

It’s great to see interesting phenomena documented. Keep an eye on it.

Comment by Katey Walter Anthony

This looks interesting, and is similar to features I've studied in other parts of Alaska. I agree that it is likely related to degrading permafrost and permafrost hydrology. Without getting out there to the site and sampling the gas and water, I would not be able to provide a more useful assessment. If this is something the community would like to pursue, please let me know.

Related Article Comment (GPT 5):

This post describes a bubbling, deepening puddle beside a roadway in Chevak that persists year-round and appears to vent gas, raising questions about whether it’s linked to permafrost thaw, a waterline leak, or gas from decomposing organics. The consults note that confirming the cause would require site sampling of gas and water, and suggest tracking changes over time and noting any odors.

Related posts help frame what you’re seeing. In Chevak, a prior observation of “Sunken Earth” documented subsiding tundra linked with regional permafrost sensitivity and reports of sulfur-like odors during thaw, aligning with the possibility that degrading permafrost and changing hydrology could create persistent wet spots and bubbles Sunken Earth. Similar bubbling features have been observed on land in Fairbanks, where methane bubbles were found on a golf course and hypothesized to be associated with rainwater pooling over permafrost and organic matter breakdown, a pattern consistent with Katey Walter Anthony’s note that this Chevak feature resembles sites she has studied For methane researcher, golf course bubbles are a first. Broader observations show that thaw-related ground instability and gas release can occur across Alaska’s infrastructure corridors, offering a caution that nearby roads may be vulnerable if thaw is involved As Alaska permafrost melts, roads sink, bridges tilt and greenhouse gases escape. Elsewhere, persistent bubbling from natural vents has been documented and investigated through gas sampling, a practical step echoed by the consults here Natural Gas Vent. Regionally, communities are expanding monitoring of thaw and sharing data, which could support follow-up measurements at this site Permafrost thaw is an existential threat for Alaska communities. This nonprofit helps monitor it. Together, the 'Related Posts' highlight that bubbling and subsidence like those in the observation can be consistent with permafrost degradation and trapped gas release, while also underscoring the need for on-site testing to distinguish among permafrost hydrology, pipeline leaks, or other sources as suggested by the consultants.