Bad smell of sh1t

tea and coffee

We got connected to the mains 7 years ago. In the last year or so there has been increasing issues in relation to sewage smell.
Basically if water dries out somewhere, the stench is like very strong sewage. For example, if the trap in the shower is left up after cleaning it and dries out or the whb isnt used for a few days and the u bend dries out , or the toilet gets a bit blocked and there is no water in the bowl...in the first and last scenario particularly, you get a horrendous sewage smell inside of an hour or two.
I'm worried that there is an issue and somewhere is a big blockage causing this back draft of stink.

I've never had this before in other houses or before we moved off the septic tank.

Furthermore, and it may or may not be a separate issue: the toilets block quite easily ( I have young children that regularly use too much toilet roll and block the toilets).
One of them leaks from the back of it (enclosed cistern) if it gets clogged - I e. Out the waste pipe. Water spills out from the cistern cover box where the waste pipe is also contained.Once it's unblocked it seems to reseal itself for the most part. Occasionally it also emits a rancid sewage smell.

bobbyy gee

Try pouring bucket of water down rack sink and bath and toilet maybe sewrage pipe is broken or blocked have you trees near by

tea and coffee

There is a tree in one area where the pipe comes out.
I shared joining the mains with the neighbour and there are no trees on his property where the pipe joins the road.
But (possibly unrelated) he built a second house on the property and connected it to the mains (all in original planning permission)

The water runs through fine. It is just if the water dries up in any toilet or whb or shower that you get this smell

Sleeper12

None of these should be drying out. I'd imagine the plumbing on the wastes are connected wrong. If so then when you use one it can syphon the water out of the other