I've got away with it but maybe I've just been lucky - a friend drank downstream from a dead sheep (as she found when she walked upstream) and suffered for it. I've seen sterilising tablets in the outdoor shops - a good shop should be able to advise. And there are filtration "straws" in third world countries where there's no option but to drink filthy water. Boiling is the easiest and least chemical-y.
As Fiona said, always check upstream, only take water where it is fast running and only from burns that are far away from sources of contamination.
Personally, I have never had a problem in the highlands but wouldn't drink from upland streams in Ireland. If in doubt, boil it.
If even I took water from the source I would still boil it as an absolute minimum. But further downstream you really cannot be too careful, the brave souls who have said they got away with, really did get away with it!
There are too many things out there to gamble your health with including Crypto, Lepto, TB etc. I spent nearly 3 decades on, in, or near the streams and rivers of Dartmoor as a career, and even if I washed my hands in a moorland stream, which I did most days, I would use hand sanitizer afterwards. We were educated to the hilt on the dangers of drinking seemingly clean fresh hill water straight from the stream.
Check upstream at least half a mile, take from running well oxygenated section of the watercourse, boil for a minimum 3 minutes, allow to cool and put it through a filter such as a Travel Tap, then decant into your drinking bottles, is one way to minimise the danger. But do your own research.
Most of our wild areas are grazed by animals, cattle, sheep, deer etc. I am afraid they are not trained to urinate and deficate well away from watercourses.
I have spent many a period of up to 10 days drinking only stream sourced water, including in Africa, and treated thoroughly should not cause you a problem. Your water admin may take time but what else are you doing! Do not let your drinking water routine slip, you may live to regret it.
Do your research into water treatment/filtration systems, and also where you will be camping. That remote farmhouse in the middle of nowhere, miles from civilisation, will have that septic tank running, or leaching into a watercourse or groundwater........You don't want your PG tips soaking in that.
The rivers and stream that I looked after were all rated A in purity, but you would not drink it straight...............EVER!
Thanks for your advice! I'm a newby with walking in and camping before a long Munro and carrying the water seems to be one of the biggest weight issues
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