https://trove.nla.gov.au/newspaper/article/220442169
https://trove.nla.gov.au/newspaper/article/107939744
> Is sewage deadly?
No, the Thames back then would have been the same as many rivers in many poorer countries today. Many of these rivers are scavenged, not without issue, but a quick dunk isn't going to have immediately killed anyone. Author needs to travel more, oldie England is still alive and kicking around the world.
An interesting aside related to the Princess Alice disaster is that the main northern sewer was only finally fully working months before the disaster and its outflow was very close to the crash site. Work began in the next decade to purify the sewage rather than just dumping it into the Thames there.
But I'd argue (and this is just a hunch) that sewage was "deadly" then in the sense that if the water then were as clean as now, the death toll would have been far lower, especially as the crash happened so close to (admittedly rather muddy) land.
More on the miasma theory of disease here: https://en.wikipedia.org/wiki/Miasma_theory
https://www.google.com/maps/place/Sheerness,+UK/@51.5112905,...
https://en.wikipedia.org/wiki/Beckton#Sewage_works
But you can't discount the difference between the dictionary definition of "sewage" versus the reality of incidental pollution as discovered in-situ.
Case in point:
https://en.wikipedia.org/wiki/Gowanus_Canal
http://nymag.com/daily/intelligencer/2010/03/post_25.html
https://www.timeout.com/newyork/blog/ten-feet-of-black-mayon...
https://ny.curbed.com/2018/7/19/17590126/brooklyn-gowanus-dr...
http://nautil.us/blog/in-the-black-mayonnaise-of-brooklyns-g...
https://www.brownstoner.com/development/gowanus-canal-black-...
https://www.dnainfo.com/new-york/20161123/gowanus/gowanus-ca...
Also: