Вы имели в виду Severn?
Зашел к ним на официальный сайт. Вот, распределение цен за что вы платите на 2018- 2019:
Вода (средний счёт за воду £180 за год) :
Maintaining our network of reservoirs, treatment works, pumping stations and pipes
Gathering and collecting water from rivers and reservoirs or pumping it from underground rocks
Storing the water ready to be treated
Treating, cleaning and distributing water to over 4m homes.
Канализация (средний счёт £169 за год):
Building and maintaining sewer pipes
Pumping sewage to treatment works
Treating sewage so that it is safe to return to the environment
Sending cleaned and treated wastewater back into rivers and the sea
Converting solid material from sewage into gas for energy.
И ни слова о дождевой воде или дренаже.
Виктор
И правда нету слова.