Sudden Intermitant Sewer Smells

I searched though the threads and didn't find a solution so here it goes.

Our 2 story house is 10 years old this year, on City water with septic. There have been no modifications or additions made to the plumbing. We've lived in the house for 5 years. The house sits 2/3 up a 1/2 acre hill with the septic down hill.

Last spring/summer we began getting sewer smells from the washing machine drain. The pipe does have a P trap and I have snaked both the drain and outside vent. There are no smells in the crawl space and as far as I know no other fixture smells. I think something is siphoning the water out of the P Trap but what? When I inspected the outside vent I did notice it had a little bit of water in it from a recent storm. I also got to thinking about a wayward squirrel that climbed down a heater vent when I was a kid and made quite a stink. Therefore, I put on a metal vent cap to prevent clogging. After installing the cap, the smell went away for about a year. Now the smell is back. I noticed it started after the adjacent toilet was flushed in conjunction with the shower being turned on; however we've done that each morning or years without any problems. Does anyone have any ideas?

pix of the plumbing in question could help

Is the toilet loosely mounted, or, rocking?

It will be a day or two before I can get under there with a camera.

I checked all the toilets and they are tight.

I had another oddity yesterday morning. After flushing and getting in the shower I heard continual glucking sound coming from the toilet. The water had been sucked down about 1/8-1/4 inch past the top of the trapway and rhythmically being sucked back and forth. By the time I finished my shower the water had returned about a 1/2 inch above the trapway. I checked the washer and all was well.

Later I got to thinking that maybe my kids flushed another toilet as I started my shower. I had the kids flush the other toilets as I turned on the shower but nothing happened.

My wife just told me she had an incident yesterday afternoon where she flushed and the bowl filled like it was going to over flow and then all of a sudden drained completely. She said that by that point she was washing clothes and wasn't sure if that made any difference.

Sounds like you might want to check the septic tank.
When was it last pumped?
You aren't in the flooded out midwest are you?

Or, the line to the tank may be obstructed.

STINKY FEET PETE said:

It will be a day or two before I can get under there with a camera.

I checked all the toilets and they are tight.

I had another oddity yesterday morning. After flushing and getting in the shower I heard continual glucking sound coming from the toilet. The water had been sucked down about 1/8-1/4 inch past the top of the trapway and rhythmically being sucked back and forth. By the time I finished my shower the water had returned about a 1/2 inch above the trapway. I checked the washer and all was well.

Later I got to thinking that maybe my kids flushed another toilet as I started my shower. I had the kids flush the other toilets as I turned on the shower but nothing happened.

My wife just told me she had an incident yesterday afternoon where she flushed and the bowl filled like it was going to over flow and then all of a sudden drained completely. She said that by that point she was washing clothes and wasn't sure if that made any difference.

Click to expand...

I would check you vent on the roof. I just faced this problem at a customers house and jetted the vents. Her sucking toilets, and bathtubs are much quieter now. Her stinking kitchen sink is smelling great too.

Jetting vents?
That sounds like a very high possibility of a huge mess!

Anytime a main drain is flooding chances are vents will not work correctly as they become submerged. Check the tank and drain line first!

Sorry, it's been a couple days and I still haven't had a chance to get under there yet.

We live just south of Chattanooga, TN. It has rained a bit lately but last year we were in a draught when we started having problems.

In the 5 years we've been here we have not had it pumped. I don't know about the previous owners-I would assume not. The house sat empty for a year or two before we bought it because it was a foreclosure. This is my first septic and I'm a bit un easy with it. I've heard so many different theory's and opinions on how often to pump and whether or not to use Ridex that I'm confused on what to do - but that's another issue.

I'm not sure where the septic cap is but I'll try to find it and check this weekend. Although, if the main drain is flooding wouldn't it be a continual problem instead of an intermittent problem?

I do appreciate all the help and will try to update as soon as I find more info.

Probably The Septic Tank

Redwood is probably right about your troubles....

you should also look for a cleanout plug somewehre
along the side of the home , perhaps the line needs to be snaked too..

it would not hurt to take the plug off to check if water is standing in the pipe , then leave it loose or off untill you can relieve the septic tank..

of course if the C.O plug sits under a bedroom window, that might be a bad idea to leave the plug off..

Septic tank cleaning is a must do maint. item for you.
If you don't do it when needed it can cost you dearly.

Rid-X is not needed as it is produced in your tank naturally and requires no boost. It is not a substitute for scheduled maint.
http://www.inspect-ny.com/septic/tankpump.htm