Stinky shower drain! I tried bleach/hotwater method, but is it time to call the plumber?

November 16, 2012 11:40 PM

Stinky shower drain! I tried bleach/hotwater method, but is it time to call the plumber?

This belongs to a house I bought 4-5 months ago, and it has been vacant for the last several months. Bathroom has been completely renovated since then (new tiles, bathware, etc).

However there is this Smell!

Tiny flies are hanging around inside the shower screen. I'm guessing they magically came from within the drain itself?

I've tried pouring bottles of bleach for it to sit, and then flushing it with hot water the following day, twice to no avail. The smell and tiny flies come back.

What could be inside the drain/pipe? Dead horse? Is there nothing else I can do?

A part of me suspects that a cause of this, is that the shower has not been used (for showering) in the last several months and therefore allowed something inside to fester.

posted by gttommy to science & nature (15 answers total)

Can you see the plumbing for the drain? It sounds to me like someone might have bypassed the trap or installed the pipe wrong.

If it's not trapped there's no water pocket to prevent the smell from coming up the main stack.

Not good.
posted by neversummer at 12:23 AM on November 17, 2012 [3 favorites]

Is there a crawlspace under your house? If so, is it possible the pipe is broken/corroded and draining into the crawlspace?
posted by 2N2222 at 12:46 AM on November 17, 2012

Something identical happened to me just last week, so amazingly I may be of some benefit, and potentially save you some cash. We have both a downstairs and upstairs bathroom. We rarely use the downstairs shower. Two weeks ago the most awful stench started appearing. I did exactly what you did, hot water, bleach, draino. I also tried handfuls of bicarbonate soda. Nothing worked. Eventually I called a plumber, thinking like you, something had died down there. Not at all. He told me it was through lack of use and to start using the shower regularly. Since then, my husband or I have been using it for one shower a day to keep water in the drains/flush them out and the smell has gone. I just went downstairs then to check.

Maybe don't call a plumber just yet, give it a week of regular use and hopefully it will clear up.
posted by Jubey at 1:28 AM on November 17, 2012

Regular use may stop it smelling but if correctly installed it shouldn't be smelling in the first place. These problems were solved long ago (1775, wikipedia says) by designing in traps like s-bends and u-bends.

It must be draining otherwise the shower would fill up when you used it. My guess is the plumbing is not draining properly, either because it was badly installed (e.g. not enough slope) or because of a blockage slowing things down, so trapped water is going stagnant

Bleach et all have their place put so does good old fashioned brute force, get hold of a plunger (or long coiled spring), put in lots of water and try dislodging any trapped crap (the spring may be more gentle but they can come back out a bit gross) ...
posted by epo at 1:50 AM on November 17, 2012 [1 favorite]

Ahhh! If not used regularly the water in a trap will evaporate, letting previously trapped gases escape. Once a month should do it for an otherwise functioning system. The fact that your problem recurs immediately indicates some other drainage or blockage problem however.
posted by epo at 2:01 AM on November 17, 2012

Yeah I was going to say blockage, unfortunately.

I mean IANYPlumber. But in my new house, there was a bit of smell, and then the next day there was sewage bubbling up on the lawn. I would get a plumber out there prepared to snake.
posted by fingersandtoes at 6:16 AM on November 17, 2012

Before I made an expensive call to a plumber I'd make sure the smell and flies were coming from the drain. A wash cloth wrapped in a bread bag placed over the hole and then weighted down with whatever is handy will block off the drain. Check back for smell/flies the next day.

(this assumes straight shower, a bath/shower will have an overflow that you can't block).
posted by Mitheral at 6:40 AM on November 17, 2012 [1 favorite]

Fill tub with boiling hot water, add two boxes of baking soda. Let drain. Rinse with more hot water.
posted by timsteil at 7:13 AM on November 17, 2012

If you have the ability yourself, you could snake the drain. It's possible there is a weird rotting hair lump and/or a dead mouse or something else in there. Either of which might smell terrible and/or attract flies and/or withstand attempts to bleach it, etc.
posted by jessamyn at 7:34 AM on November 17, 2012

Seconding regular use. We moved into a rental that had been vacant for a while, and the smell was coming out of the kitchen drain. I did all the stuff--bleach, soda, vinegar, lemons in the disposal--and nothing seemed to work, but as time went on the smell just gradually vanished.
posted by scratch at 8:03 AM on November 17, 2012

For the time being, keep the drain plug in it when you're not using it.

If you've poured bottles of bleach down it and the smell returns quickly, I'd have to agree with neversummer, that you might have a drain that's running directly to the sewer stack without a trap to intervene.
posted by bonobothegreat at 10:48 AM on November 17, 2012

Before calling the plumber, pour in some baking soda, then some vinegar. It foams up and can help dislodge gunk or a small blockage. Follow with boiling water.
posted by theora55 at 11:46 AM on November 17, 2012 [1 favorite]

One of the major causes of smelly drain is "trap failure." There's a u-shaped bend in the pipe -- the u has water in it at all times, and that prevents smelly gases from wafting into the living space.

Various things can cause trap failure. A common one in showers is capillary action: strands of hair hang over the bend in the drain and draw water out of the trap. Bad venting is another thing to check out. Here is a good explanation with lots of details.
posted by wryly at 1:03 PM on November 17, 2012 [1 favorite]

My bathroom sink drain was smelly & slow draining. Cleaning out a disturbingly large hair ball with a disposable zip strip fixed the slow draining, but the stink kept coming back and bleach was not knocking it out. A few rounds of treatment with this enzyme cleaner finally took care of it.
posted by superna at 1:06 PM on November 17, 2012

Thanks for the various ideas guys. I have come to the conclusion that my drain does not have a trap, therefore the smell was probably coming from the drainage system further up the chain of command. The plumber got this quick fix installed and it is working fine so far!

http://www.grateseal.com.au/contact.html
posted by gttommy at 10:46 PM on December 17, 2012