Septic Tank Odours

[Rob5060]

We have 2 septic tanks at our house and have them pumped clean once a year

However when we flush the toilets there is a bad smell outside for about 5 minutes

Anybody know if this is normal or can we do any more to avoid the odours

Cheers

Edited January 1, 2013 by Rob5060

[lopburi3]

You do have a pipe higher than home to vent?

[ronz28]

We are on a city sewer system and don't get that. I suspect something is wrong with your plumbing. In city systems they do a smoke test and inject smoke in the main lines and look for smoke coming out where it shouldn't be to identify broken or cracked pipes. Maybe there is something like that for septic systems. During the smoke testing it is normal to see smoke coming out of the plumbing vent pipes on your roof. Maybe you have a cracked pipe or one not connected properly?

[jbrain]

We are on a city sewer system and don't get that. I suspect something is wrong with your plumbing. In city systems they do a smoke test and inject smoke in the main lines and look for smoke coming out where it shouldn't be to identify broken or cracked pipes. Maybe there is something like that for septic systems. During the smoke testing it is normal to see smoke coming out of the plumbing vent pipes on your roof. Maybe you have a cracked pipe or one not connected properly?

Plumbing vent pipes on the roof ?

You realise this is the Thailand forum yes.

[TS79]

We get it occasionally (once or twice a year) and to solve it we flush a small box of the powdered poop eating bacteria down the toilet.

More bacteria in the septic tank seems to equal less odours. Can buy the box of stuff in Home Pro for about 20 baht.

[rattler]

If it smells its aint working properly

[sirineou]

most of the answers are correct

when you flush the toilet the flush water displaces air from inside the septic tank, this air comes out the vent pipe, if the vent pipe is not higher than your roof it will find it's way in the house, thus the smell

A proper bacteria colony in your tank will increase it's efficiency so what TS79 suggested will help both with the smell and will increase the length of time between pump outs

but some smell will remain unless you have your pipe higher than your roof, as suggested by Lopbury3

Edited January 1, 2013 by sirineou

[jbrain]

most of the answers are correct

when you flush the toilet the flush water displaces air from inside the septic tank, this air comes out the vent pipe, if the vent pipe is not higher than your roof it will find it's way in the house, thus the smell

A proper bacteria colony in your tank will increase it's efficiency so what TS79 suggested will help both with the smell and will increase the length of time between pump outs

but some smell will remain unless you have your pipe higher than your roof, as suggested by Lopbury3

Would higher then your nose not be sufficient enough

[ajahnlau]

Throw a couple packets of salt in toilet and flush.

[sirineou]

most of the answers are correct

when you flush the toilet the flush water displaces air from inside the septic tank, this air comes out the vent pipe, if the vent pipe is not higher than your roof it will find it's way in the house, thus the smell

A proper bacteria colony in your tank will increase it's efficiency so what TS79 suggested will help both with the smell and will increase the length of time between pump outs

but some smell will remain unless you have your pipe higher than your roof, as suggested by Lopbury3

Would higher then your nose not be sufficient enough

Dont know how high your nose is but No,

not sufficient for most peoples noses

The vent pipe need to be high enough for raising vapors to not enter the house and to be able to be dispersed by wind currents.

[lopburi3]

Plumbing vent pipes on the roof ?

You realise this is the Thailand forum yes.

Yes - and they indeed do use vent pipes here (but often only into attic area) and often only water pipe size and can become blocked during flooding so may have to be cleaned out with a blast of water or air to allow venting function to return.

[Greenside]

No one seems to have mentioned that if your tank(s) need cleaning out once a year then your system isn't designed or working properly. A properly installed system of the right size for your house shouldn't need cleaning out anything like that frequently. The smell issue is probably the venting issue as mentioned above.

[jbrain]

Plumbing vent pipes on the roof ?

You realise this is the Thailand forum yes.

Yes - and they indeed do use vent pipes here (but often only into attic area) and often only water pipe size and can become blocked during flooding so may have to be cleaned out with a blast of water or air to allow venting function to return.

How can a vent pipe in the attic become blocked during flooding?

[lopburi3]

By floating excrement being pushed up into the pipe inlet from toilet drain or septic tank and causing a blockage.

[jbrain]

By floating excrement being pushed up into the pipe inlet from toilet drain or septic tank and causing a blockage.

Thanks, I hadn't taken that into account.