Seems like the best option so far is Chris' idea about simply digging a hole in the ground. In a survival situation I fully realize that you drink whatever you can find and if purification means drinking downstream of the rapid areas then sure you go with the best that you can muster up with little energy expenditure. This however is not a survival situation. I put myself out there like this intentionally on a regular basis so I really don't want to be visiting the doctor afterwards. <img src="/images/graemlins/smile.gif" alt="" /> Perhaps I should just keep bringing the boiling tin or the MP1 tabs and a water bottle and be happy with that. <img src="/images/graemlins/frown.gif" alt="" /> Either way I am going to see if I can dig a decent hole in ground and boil in it. After all that's why I do this is to try out new things and hone my skills (and of course I enjoy it thuroughly too). <img src="/images/graemlins/smile.gif" alt="" />

If I can get it down to clothes, knife, and a tin cup (or water bottle and MP1 tabs), that is still better than where I'm at right now. BTW I have tried replacing the tin cup with foil a couple times. I am apparently no good with the foil. I always spring a leak. <img src="/images/graemlins/grin.gif" alt="" />