Anglian Water are flushing out the mains in our area soon and they sent
us a circular about it. I think they must be used to getting complaints
from people seeing all the water going down the drains...

What happens to the flushed water?

The water that is flushed out of our mains is not wasted, but is
returned to the environment by a network of sewage and drainage pipes.
The water then runs into rivers and streams, and can actually help
support these rivers is low rainfall levels leave some of them to
run dry.

Nest time we have a drought, I'll be sure to leave all the taps running
to keep those rivers and streams )

Cheers,

Colin.