Seriously smelly drains

[Marijn]

Does anyone know how I can remedy smelly drains. I've had every man hole cover up, and looked at all the drains that guttering and down-pipes are running in to, and there are no blockages. The water is running freely and the water is clear, but there's still a horrible smell and it permeates through the house. Any ideas what I can do, it's been like it for weeks, and I don't want to just mask the smell. I also put powerful plug hole unblocker down the bath plug hole, but none of the plug holes are blocked anyway. Any good ideas gratefully received, thanks.

[Marijn]

Thank you all so much for your answers. I've had a good ol' sniff round the dishwasher, and that doesn't smell at all. The smell is mainly in the downpipe drain in the garage and the down-pipe drain near the front door. I will investigate all your suggested possibilities.

[MichaelZZ]

Can you actually remove the drainpipe - or at least a section of it - to see if there's something not very nice in there (abandoned nest / partial blockage due to leaves or other debris off the roof)?
I had a similar problem a couple of years ago and by removing a length of drainpipe and taking didgeridoo lessons, I was able to release a "bung" about a foot long which was the cause of the problem. (I was lying about the didgeridoo lessons, but you take the point!)

[Marijn]

That's a possibility Michaelzz, I will see if I can dismantle some drainpipe that's just inside the garage, because that's mostly where the smell is worst. Thank you.

[pinkgin]

Hope you come back and tell us all what was causing the smell and whether you have finally eradicated it?

[Marijn]

I haven't solved it yet. I have run fresh water down every downpipe and drain. I have used lots of Jeyes fluid too. There seems to be no blockages on my property, which I can tell because I have had every man hole cover up. I now know where every gulley runs to and from. I will investigate all the other possibilities that have been suggested to me. I didn't fully understand all of the suggestions because some of it went over my head, but I will get someone to read them with me, and I'll make sure I follow up every lead. Thank you everyone.

[jomifl]

notafish, can you describe the smell? it would help.

[Marijn]

Rotting damp mouse smell. But it can't be that because there's nothing to be seen.

[jomifl]

Damp mice can rot and smell in cavity walls as well as floor voids. If it is a rotting corpse (hopefully a small one) it will disappear eventually. No sign of flies showing an interest?

[what..the?]

I think the problem you have is the same I have, but for a different reasons. It's smelly drains linked with bad traps and valves in your property. I have had some very bad building work done and on my main foul down pipe there is supposed to be a valve and they forgot to fit it, it stops the smells from the drains coming into your property also I suspect some of my traps on shower. toilets and bath haven't been fit properly. (A trap it a bend in the pipe with means water sits in the pipe, therefore a small at one end can't flow through when i hits the water in the pipe, so smells from the drains don't come through the pipes into you bathroom). So you possibly have plumbing (poor/dry trap) and/or broken down pipe valve, and/or a blocked drain further down your drain outside of your property limits. So maybe ask the neighbours if they have smelly drains, it might be if the drains all link up with your neighbours the water board pays to fix/test or you all share the cost to unblock? Ask the neighbours would be my first thing to do and perhaps try and find some other manholes down stream to lift.

[Marijn]

I don't think it's a rotting mouse because this smell has been going on for over two months. Some of the bits I don't understand are "air trap", "valves" and "soil pipes", I know what the actual words mean but don't understand what they are in relation to plumbing, that's why I will ask someone to read through all these answers with me, and help me check it all out. Thanks for your help it's really useful. I really want to get this problem sorted.

[what..the?]

small = smell

sorry

[Marijn]

My neighbours either side of me don't have this problem. One of them has been trying to help me pin point it. There is a bad drain smell about six houses up from me, you can smell it fairly strongly as you walk past. The smells are usually worse after it's rained. I'm off to bed now, so please excuse me if someone answers and I don't read it until after work tomorrow. Thanks for all your help.

[what..the?]

airtrap - as described, it where the pipe bends so water sits in the pipe and it stops the smell traveling

soil pipe - this is the main 'poo pipe' it would be located on the outside wall of you house from you bathroom down or inside the house boxed in under neath you bathroom. it takes all the water from the toilet/shower/bath away to you main drain. It you have more than one bathroom you may have more than one.

[what..the?]

so it could be the smell from down the road, could you lift any manholes further down the road? Or trace you drain ....does your drain link to down the road, if it does....well a) contact the local board about the smell, if it doesn't improve b) seek the help of a local recommended plumber about your air traps/valves

[Marijn]

Thank you