If you look on the web, you can find a site that pretty much states “Although the water in the creeks looks crystal clear it is not safe to drink. If you must drink the water is should be boiled for at least 5 minutes.”
That is not a good sign.
I called into the park to ask a few questions. It doesn’t sound like I’m at a high risk, since the water I drank from isn’t far from the source. They still suggested I go see a doctor. I’m feeling fairly good. I’m beginning to suspect that the burping and stomach irritation I’ve been feeling is because I’ve also been drinking milk that expired (according to the best before date) two days ago. (Friends insist that doesn’t mean it instantly goes to undrinkable, so I’ve been playing with the ragged edge of disaster.)
I also found out that there is plenty of water in the park. If I had continued on the trail for a bit more, I would have found a drinking tap. All the campgrounds have one as well.
So now I have to go back and prove I can do this properly.