Sewage smell underneath bathroom after rain - why?

Question

Hi

After a heavy down pour, I have started to get a horrible smell in my dining room (which is under the bathroom) as well as the bathroom itself? Any ideas before I call out a plumber?

Answer 1

It's very unlikely to be the bathroom if the problem occurs only when it rains, especially as the bathroom is above the dining room.

What you don't say is whether or not you're in a basement or not.
So I'll assume you're in a standard semi-detached house with front and rear garden with side path.

To start with, I'd suggest that you visually inspect any manholes you have,check that they are clean internally. It's quite easy to open these, just use two screwdrivers to lever up the cover, once a fingerhold is made, with a straight back and bent legs, lift the lid up and away from the chamber. If you're fastidious, wear gloves, if not, clean hands thoroughly before performing next brain op.

You don't need to be a brain surgeon to tell if you're drains are clean.

Next, preferably with a friend's help, flush the loo a couple of times and guauge how clean it's running. Then, flush it again with a handful of loo roll in the flush, this way you can check if the outlflow is snagging anywhere.

Again, if poss, check the whole sequence from the back to the front of your property.

Some things to note:
*If you're in rented property, it's the Landlord's problem.

*If the blockage is in the front garden, and you have a drain from another property running into your manhole, then your drain is classed as a Sewer. in this case any problem becomes the responsibility of Thames Water (in London) or your local utility company. In certain instances, the Department for the Environment will send a team out. I've done this historically to great effect. And it's free!!!

Most people assume that if the blockage is on their property then it's their sole responsibility. Not so!!!!

Anyway, back to the problem...
you say it happens when it rains. In this case check any rainwater gullies at ground level, especially those near earth/foliage/bushes etc. as it's here that leaf detritus can collect and rot, and this causes smell.

These are really easy to clean, lift out the cover grille, and stick your hand down, your trying to find a U-bend (the trap), mostly it's about 18-24" down. Here you'll find grit, small stones, and other bits of garden spoil, just pull it out and keep going. It's a bit grotty, but fun. Once you've got most of the rubbish out, stick a hosepipe down and rod it with the tap on full, you'll see and remaining crap flush out through the nearest manhole.

If you live in a converted house, or building work was done on the cheap historically, you might find that the builder/plumber ran your kitchen drain into a rainwater gulley, or vice-versa. So you might have rotten food deposits backing up. These are easily cleaned with a garden hose, bendy wire gloves and a facemask.
Resist using caustic soda, hydrochloric acid and other strong cleaning fluids etc as they don't really help treat the problem, only the symptoms.

Try not to employ a drain expert at this stage, as they're very carefree about using chemicals which are both expensive and environmentally unsound. With a deep breath and a bit of committment most householders can deal with their own drain problems.

Regard this like changing the oil in your car. It should be done without fail once a year. A little regular cleaning will go a long way to preventing fouling and consequent £500+ bills.

When it rains next, use your nose and search out the source. Happy hunting. HTH.

Px

Answer 2

Call the plumber. Not only could there be a block, you could also have a leak (horrible thought). If you have a sump pump, check that. Has there been any construction or such that may have changed the grade around the house, thus preventing runoff from getting far enough from the house?

Don't forget the sanitary stack on the roof.......those pipes that come up through the roof. They get clogged from leaves, birds, etc and affect how water runs through the sewer pipe...yes, it's all interconnected: air pressure. Most plumbers over look the sanitary pipes, vent pipes, whatever you want to call them.

Answer 3

If you have a septic system with a tank and lateral field you probably have a run off water problem. If lateral field is in low area rain water saturates the ground preventing percolation of water from septic system, resulting in back up of sewage in drains and even vent pipes if tank is full. If sewage backs up past a trap in will allow gasses to enter your home through any drain or sink. Even a crack in a plugged vent pipe could back up a leak gasses into house. Call a septic tank cleaner first then call a plumber if needed.

Answer 4

Take the side panel off your bath and have a look. You may find that it's running down your wall and settling there. Stagnant water stinks like farts if left long enough. Don't get a plumber in yet, they do a sterling job but are really expensive and if it is what i think it is they'll probably charge you more like a car mechanic does when you don't know anything about cars. You could also have a look in your drain pipe to see if that's blocked. ;)

Answer 5

Blocked drain. One method that may work to unblock is to fill all the sinks and baths in your house and take the plug out simultaneously. Or put some dreadful chemical down like costic soda. You might need a drain man to come though.

Answer 6

Broken drains,plumber wanted

Answer 7

There could be something blocking the drains and when it gets wet it gives of a sewage smell.

Answer 8

Sewarage is allowed to go into drains in higher quantities when it rains as more water to dilute it. Check you not got some blockage, perhaps your stink pipe blocked too?

Answer 9

you need to call a plumber it sounds like a drain blockage somewhere and you dont want sh.it all over your house so call one out and they will stick a camera down your bog to see if there is a blockage.

Answer 10

Call a plumber, and speak to your insurance company. They should pay, if it gets worse and floods,, they'll have to apy a whole lot more.