[wirrbel]

I grew up swimming in our local river. Obviously the river Thames is a different kind of beast with currents, etc.

However I nowadays would be very reluctant for swimming in rivers as soon as one is downstream of a sewer leading into the waters.

Furthermore the river I swam in is downstream of an area that industrially was heavily involved in galvanics. While the water itself is clean, who knows what heavy metals are still in the river bed and mud.

I can only imagine what the mud of the river Thames and its sources contains.

Oh and even in the mountains I remember how - on a hike - a friend contemplated drinking from that clear water stream shooting down the rocks and was glad not to have done that after seeing the poop from geese and cattle just a 100 m upstream.

Amoeba, E. coli etc are not fun.

[jeffwass]

Regarding drinking from streams, back in the mid-90’s I did a camping/hiking excursion with Outward Bound in the Appalachians of North Carolina.

We sourced all our drinking water from streams, using concentrated iodine to make the water drinkable (I think we had to wait 30 mins for it to take effect).

There was one part of the journey where we ran out of water and couldn’t drink from a nearby small river because it was downstream of a paper processing factory. And we had to go out of our way using old school topographical maps (which we used for all our navigation) to find another water source and hope it was available and flowing.

[wirrbel]

My comment of course was primarily about the swimming part (you involuntarily swallow some water).

Youtube is full of methods for making water safe on hiking trips / camping etc. Boiling can also be a honking great idea of course.

[hn_acker]

Boiling helps with bacteria, but not with toxic chemicals from factories. You need to capture evaporated water (or steam from boiling the water).

[taneq]

Never drink from a river that’s downstream of farm land (without thoroughly boiling the water), either. You might be thinking ‘yeah, cows and sheep poop outside’ but they also sometimes wander off, die and leave their rotting corpses in the stream.

[pixxel]

> Never drink from a river that’s downstream of farm land

This. More so I’d be concerned about pesticides (arable).

[zabzonk]

i worked for a university of london microbiology department in the early 80s, and one of my least favourite tasks was to go down to the thames (i used steps outside the national theatre) and get a couple of litres of river water for the students to experiment with. jesus, you would not believe the bacterial load in there! but i believe things have got better since then.