???? I thought older properties are shared - newer separate - and newest rainwater goes to soakaways . Anyway, keep us posted.Well, the plot thickens!
He said in newer properties they are combined but as mine is older (30s) there is a surface water line for our properties in my terrace AND a foul line (which I don’t have a manhole for)

My neighbours baths etc are not flooding it.
OP,
you have a baby.
you have contaminated water swilling around your yard, and bursting a manhole.
unprotected, you have been reaching into a contaminated gulley.
you should stop now & call in a local plumber who clears drains.
thanks for your post - i put my post up just after your post #38, without seeing your post - i then attempted to edit and remove my post.
i am chilling, i'm especially inclined to chill when i see dangerous advice and dangerous activity by fools, and by those who should be responsible, careless of the health of the vulnerable who depend on them.
no need to say anything more - you've got four likeable stooges who delight in that kind of thing.
just saying but "political correctness " means something way out of whatever it is you are trying to say - check out the definition. learn something, be on a roll.
although, i doubt that any definition will show a link between hepatitis & PC.
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