Northwest Dive Club

I think there might be a dive-able cave in SW WA. Theres a big lake with no outlet, then about half a mile away, water springs out of the ground. There is enough water to create a rushing creek, out of several places in a small area. In particular, there are two sizeable boils on the surface of the water. Judging by the volume of water, and the localized nature of the outflow, there has to be a conduit that the water is flowing through. Im imagining skylights in a lava tube. It could turn out to be nothing, but I'm headed back there with my mask and a light (no dive gear) to see if there is a hole in the ground I could squeeze through. Anybody interested in a little recon?

Watch this before you go.

http://www.youtube.com/watch?v=AEtbFm_CjE0

Is this area kind of a marshy lake in the trees or a lake?

Their are several old coal mines that are flooded. the main sites of were the mines are are under water and they have a very good flow of water coming out of them. If you do venture in be careful. they have miles and miles of crisscrossing tunnels and will silt out easily.

selkie wrote:Watch this before you go.

http://www.youtube.com/watch?v=AEtbFm_CjE0

Scary Video!!!

Its a good size lake. Looked briefly at a lake bottom chart, and i think it gets to 70 or so in the deepest spot, and is 3/4mile long. Current thinking is that the lake was dammed by a lava flow. It is on the southern slope of Mt St Helens. I really don't see much potential for differential pressure as the water is escaping to the surface and i would be going in at the downstream end. The water coming out would be a geyser if it was under enough pressure to create a hazard, and i wouldn't be able to get in the hole. It seems apparent that there is a conduit that a fair volume of water is flowing through, but it is unclear as to whether that conduit is a localized lava tube or just a pervasive weak layer or set of fractures. I was a geology major in college, and studied volcanology, and am contacting old professors. Im going to shine a light in first, and bring some gear back if it looks promising. I've got my CCR Cave and Cave Survey c-cards, and i will definitely be careful. Headed up there around the end of the month, will keep this thread updated!

Let us know how it went, I'm guessing it's under the basalt, which seems to be where the flow from some of the small streams inside a few dry lava tube caves are from. The water runs under and out, but that would leave a basalt ceiling, with sediment errosion tunnels underneath, would be my guess. There's a few lava tube springs under the rivers down there, haven't found one large enough to enter yet...

Kind of like these in Lake Cave down by Mt St Helens.

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