Exactly what I said earlier John, of you have that kind of gear, its as good as your gonna get.
Home from Home
The point I was trying to make was that boiling will not kill the chemical content, and that can be very nasty, and stay in your body creating havoc for years.
UV, charcoal filters, RO filters etc can all be used to good effect. You may even end up with better than at home.
In fact - boiling CONCENTRATES the chemical/heavy metal/non living polution......
In Ghana we were drinking the water from lake Volta ...at the end of the dry season when the first rains were washing all the years carp into the water causing algal blooms, plus there were filthy ferries, villages with no sanitary treatment etc etc.
We filtered (Katadyn ceramic jobbies) and heavily chlorinated and apart from the water still stinking and the chlorine making me want to chuck all the water I had just consumed (we needed to take on about 9liters per day as it was a tad warm for long distance canoeing....) we were fine.
I had a detailed medical after we returned (mainly to check for a problem I developped out there - possibly gall stones but most likely a virus [could possibly have been waterborn but I was the only one to suffer] - and for bilhartzia(sp?).
I was, acording to the docs, "free from any problems." - and that is in a bilharzia endemic area with high levels of organic, chemical and other pollutants.
The only boiling was for cooking and tea making reasons - not for purification.
Check your local water supplier - a good number of English cities abstract water in Wales, a large amount of drinking water in the UK is abstracted from rivers and London water has passed through a lot of kidneys before it gets back to your tap!
In the UK hills I would normally be happy to drink from the streams above habitation level after just boiling the water.
In lowland areas I would want to give any water the full filter and boil or filter with RO and UV etc to remove as much chemical etc as well as bacteria, cysts, viruses (which I would PRESUME are in lowland waters) as possible.
Some chemicals (it would seem) get through any process and are in our drinking water anyway.... some of Cumbria is still radioactive after chernobyl....
The only way to get pure H2O is in your home lab!
Do your homework and treat your water accordingly!
Nigh on 40 years of following this regime and I do not seem to have developed any long term health problems - except for the beard.... and a distrust of tap water!
Dammit it comes from a river I canoe on and I know my boat is dirty!
Follow WC Fields advice ..."...never drink water - fish F*** in it!" and you should be fine!