clch - hours for sewage discharge [2020]

Although the UK's water treatment plants [sewage works] are designed to cope with storm water, usually by filling storage ponds / tanks, there is a limit to the volume of these facilities. Once filled, the incoming flow is diverted, and storm water is discharged - usually to rivers.
The intention is to catch the dirtiest water - from the first flows in storm pipework - and retain it for treatment. So, what follows should be "normal" flood water and suitable for discharge.
Unfortunately, in recent years, too much storm water is actually entering the normal foul water system, instead of "soaking away" into the ground and the system is unable to cope, so again, flows are discharged that should be retained.

Overall, the weather seems to be getting wetter, plus areas being over-developed, which means an old [Victorian, in many areas] sewer system that has too much to carry anyway - and frequent "fat bergs" - therefore this problem continues to occur, and at an increasing frequency.

Basically, it's raining more onto an often outdated & under-sized system already suffering with chronic under-investment [that now has to satisfy shareholders, not customers] ...
[comments are my own opinion, based on my academic studies & qualifications]
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