Methane bubbles from vegetable matter trapped at the drain? Someone opened the spillway after winter accumulation? The "Ah that stinks" is a a "dead" giveaway.
I expected them to know what it was they seem experienced 😩 as someone who is deeply afraid of water I literally got scared for them when they went closer to it 🤦🏾♀️
I could have sworn that I seen what looks like a periscope go under the water right in the middle of all the bubbles after the big explosion of gas or bubbles or whatever. Probably just a log but it's crazy how fast it gets pulled under.
Whenever you see that, you want to get as close to it as possible, on top of it if possible, breathing deeply, and then maybe even take out a lighter and use it