Back in the 70s I campewd at the Narnain Boulders on the Cobbler and used water from the main stream. The next morning I saw a dead sheep less than 100M upstream. No ill effects. But subsequent advice I was given makes sense – drink from the small streams and there is less chance of anything being in the water upstream.

In the highlands I’ve always drunk water untreated from streams above the last house/farm and never had a problem. My dad has been drinking from the streams/lochs in the highlands since the 1940s. He’s still going strong at 83. Still does a bit of hillwalking. Never had a problem with water.

But if you don’t feel safe doing what other people have done for decades get some tabs. I’m going to be using Katadyn MicroPur Purification Tablets for a USA tour this summer. Claimed to be “The Only EPA Registered Purification Tablets on the Market! And the only disinfection system effective against viruses, bacteria, cryptosporidium, and Giardia.”

Viruses and bacteria are killed quickly. Cryptosporidium, and Giardia take from 30m to 2 hours to be killed depending on water temperature.