Look for mine tailings and look at your map. Usually, there are markers for mine adits located on USGS maps. If there is mining activity in close proximity to your water source, get it somewhere else. If you are in a heavily mined area, don't drink the water, especially if the mining activity was large enough to be an ore processing area. Lots of heavy metals were used in ore processing. Mining activity above you in the drainage you're in, drink at your own risk.screeman57 wrote: Getting sick because you didn't know that Matterhorn Creek has high levels of heavy metals is, in my opinion, as unnecessary a part of "the adventure" as getting caught in a blizzard because you didn't check the forecast.
But seriously, the Colorado mountains are not the Sahara desert. There's water EVERYWHERE. Carry a reasonable amount of water given the rate you drink it, and carry some water tablets in your first aid kit to treat any water you may need to supplement what you brought with you. It might not taste as good but it will get you through ok. You can also carry a steripen if you're worried about Iodine or Chlorine tabs not being totally effective. A steripen weighs ounces.