Should I worry about industrial and agricultural run-off when collecting drinking water in the wilderness? - from Mary, camping outfitter
Wow, lots of great water questions! I myself go backpacking quite often, and collect my drinking water from lakes and streams in the mountains. The answer to your question, Mary, really depends on where you are in the wilderness. In the Rocky Mountains about 10,000 feet or so, there is no agricultural or industrial run-off. There might be a stray mountain goat, but no pesticides, herbicides, industrial chemicals, or the like. It is probably the cleanest water up there you'll ever find. The Midwest, however, has some of the dirtiest waterways in the U.S. The Mississippi, Missouri, Ohio Rivers, etc. are filled with pollutants from sewage, farms, factories, etc. In fact, in my native land of Iowa, some companies will not sell you a water filter for camping use because they are afraid you will try to use it in an Iowa river. The East and West coasts are not safe either - they also have some very dirty rivers. In general, don't drink water from a major river with lots of tributaries and a large drainage area. Smaller streams and springs are cleaner and have less chance of contamination. Water in the true "wilderness" is very clean. The Rocky Mountains, the Sierra Nevada, high up in the Appalachians, deep in Minnesota's boundary waters, etc. have great clean water. You should always filter your water, though, to remove bacteria and protozoa. Typical water filters for camping are designed to remove bacteria and protozoa, and some methods like UV treatment and iodine tablets also kill viruses, but they do not affect chemical contaminants. If you are concerned about a water source, an activated charcoal filter is the best way to remove pollutants. There are a few brands that make portable combination ceramic/charcoal filters. If you are traveling in a foreign country, be sure to research the water quality beforehand to see what methods are necessary to ensure safe drinking water.