How clean is the Thames?

Earlier this year had the dubious pleasure of rolling a kayak in the Thames, and getting much river water up my nose, in order to show I knew enough rescue technique to get a BCU two star qualification. Two of the group refused, having heard bad things about the water.

However nothing bad seemed to come of it (that I've noticed anyhow) so wondered if the Thames has been maligned and left it at that.

On a separate tack had also been wondering what the tourist boat commentary is as they go up river to Kew. They go past and all one can hear is "On you left waw waw waw", so intrigued I decided to pay the ten quick or whatever it was to get a bit of education.

However I seem to be very unlucky. Having got on Westminster, we headed up past Parliament, on to Vauxhall without a single "waw" let alone more useful instruction. On asking it turns out to be a voluntary task the crew can do or not do as they wish, and in this case they "couldn't be arsed" in the colourful phrase of the chap who served coffee. In their defence a particularly noisy bunch of school kids meant very little of what would have been sent would have been heard.

Was therefore forced to pay another 10 quid on another weekend and pretty much the first thing on getting onboard I did was to ask and yup due to public pressure we got a most excellent commentary - well at least for the first half of the trip.

So to date still don't know what the "to the left waw waw waw" is for the river around Putney and no doubt will have to wait till next year.

But one gem they said was about the river and how clean it is. "Just get a bucketful of water" we were told "leave it overnight and all the mud will drop out leaving sparkling clear water"

This I had to try. Buckets being a bit heavy this scientist went down to the slipway by The Boathouse jam jar in hand to get his sample and took a picture the day before and the day after (above).

And Yes! it is clear that most of the murk is indeed due to mud that will settle given time without the constant swirling of the Thames.

Alas that's not enough to recommend partaking in this particular brew. Because anyone who was been on the river for more than a little time will have spotted the odd condom floating by, or wondered where the sewage waste goes from all the house boats dotted along its banks.

But it doesn't seem to harm the very plentiful fishes or the river birds that feed on them (as posted earlier). And I've twice now heard stories about rowers drinking the stuff in the days before water bottles.

So if pushed to drink Thames water (and I would have to be pushed) my choice would be to let it settle overnight, skim off the clear upper bit, and then boil it like there was no tomorrow.