Join Date: Feb 2007
Location: Spain + Germany
My Motorhome: Four Winds RV
Thanked 533 Times in 497 Posts
It doesn't make sense Jean because unless you see turds and paper going past you can't know what it's intended for Jean. Even when you do see turds it could be a motorhomer a short distance away tipping his cassette down the nearest manhole to where he is.
To be sure you'd need to trace it all the way from where the toilet waste exits a building. Just lifting a manhole cover for a look is not a good idea and there in no possible legitimate reason for you to do so.
Drainage of all sorts was part of my work. Best avoided I think.
I carry keys too but will only lift a manhole cover to empty our tank into it if the landowner has pointed it out as a suitable disposal point.