Vents and smells

I have a question about an odd odor that just appeared the night before last. We live in a single story bungalow. We have very simple plumbing, a kitchen sink, bathroom sink, toilet and bathtub which all lead to the basement. All of these fixtures have S traps and there is a vent for the system exiting the roof. We are attached to a septic system.

Two nights ago I had ran a hot bath. Upon letting the water out we noticed a septic or strong organic smell eminating from the basement. It was not coming from any of the drains or fixtures upstairs. It was raining that night and rather windy.

My question is, could the weather (wind and air pressure) have caused the gases being released from the vent to be pushed back down into the basement? We have not ever had this problem before. The next day we had the septic tank pumped (it was due this month) and we have had no problem since. I ran all the taps and tub last night trying to get the odor to occur again with no luck.

I assume if there was a plumbing or septic problem that the smell would be constant, not just a one time event.

Any advice?

Where is the laundry drain and is ther a trap on it?

It could be that the septic started to back up and air escaped through a trap giving the smell. If that was the case it may not happen again soon.

We don't have a laundry drain in the basement. The laundry used to run into a large wash tub that does not hook into the septic but runs out as a seperate gray water line. It does not have a trap but is also never used.

How old is the bungalow and what is the drain material. Copper, plastic, galvanized pipe?

Hi,

The bungalow is 28 years old and all the drain piping is plastic.

The best way to find it is to duplicate the problem, which you may not be able to do now. Other than looking for a cracked fitting / pipe ect. there is not much you can do without the problem presenting it's self.