As well as the Waterblitz, we have another annual event (see here) https://alisonfure.blogspot.com/2016/04/sewage-spills-into-hogsmill-river.html https://alisonfure.blogspot.com/2018/10/sewage-spill-green-lane-recreation.htmlin Kingston.
It usually involves surcharging manholes spewing sewage all over the the Green Lane Recreation Ground and related sites so that the public open space has to be closed for a month. The sewage weirs over the walls into the river and we have to listen to several weeks of homilies such as it will never happen again, it was only of short duration, there is no proof that it went into the river, etc. etc.This sewage spill occured less than 24 hours after I took a Waterblitz sample from this location on 24.9.19.
Meanwhile at one of the worst areas where sewage leaching into the river is part of the operational strategy-300 new homes are planned by Fairview Homes at the former Homebase sitesee here http://fairviewkingstonroad.co.uk/proposals/