Septic Smells

[the old grind]

What I've always been told, .. pumping can cause as much trouble as it fixes. Also, I am fully aware that by the time you notice a problem, it's probably time to replace the drain field.

Could the field be slow enough to push out some gas (below all traps btw) during high use but not slow enough to back up into a shower/tub or floor drain. Glad that hasn't happened yet, but ...

btw, right away I'd divert the washer water (gray vs sewage) out of the system.

 

[paulsharvey]

I'm wondering if the system gets so little load that it doesn't get full enough to get to the drain field/effluent discharge, whatever he has. Even still, the easy best gets is the lid isn't sealed but it could be several different things. The fact that the smell is outside points me to tank/lid/effluent lines, or a crack in a pipe from the house to the tank.

 

[CADplans]

I'm wondering if the system gets so little load that it doesn't get full enough to get to the drain field/effluent discharge,

Back when I built my shed, I had a few extra $$$,, so I put a 1,000 gallon septic tank in the ground. It is a concrete tank.

The hope was that if I run rain water into it long enough,, the debris in the gutter water (leaves, seeds,, etc) would seal the tank enough to hold water,,

Basically ,, it would be a cistern, i could water the garden,

Well,, the roof feeding the tank with water is about 2,000 square feet,,
The septic tank gets PLENTY of water,,

I installed the tank in 1999,,
that is what?? 25 years?? the tank has NEVER been full.
A few minor cracks,, ALL the water escapes.

Possibly the best thing the OP could do is run a gutter into the septic tank.
Get the effluent moving through the tank, so that it works like normal.

 

[grsthegreat]

My concrete septic tank was 1000 gal piece o cra*. It continually leaked at the mid seal. Had it ripped out of the ground 5 years ago and installed a 1000 gal poly tank. No leaks. Much better.

 

[paulsharvey]

Anyone who has worked on a sanitary sewer utility will be familiar with the fights against InI. Infiltration and Inflow. It's kinda the exact opposite issue; it's ground water getting into the sewer, and needing treated, which is expensive. Common causes are manhole lids (inflow), water just running in at the pick hole, if the MH lid is in a low area, the annular space at pipe penetrations; we now use rubber boots, but in the older days, it was brick and mortar. Cracked pipes, brick manhole structures, ect, all allow ground water to enter the system. So, now almost all utilities have the MH coated in bituminous coating, and in some cases, epoxy lined, or fiber glass welded liners, slip lining pipes, even foams that are injected through the walls to keep water from getting in. Clean ground water getting in is the issue, not so much some 99% water, with some 1% solids getting out, isn't really the issue.

Point being, concrete leaks.

 

[airbiscuit]

Off topic, but the heading reminds me of the kid describing his dad. "My old man can't see, and he can't hear, but he still smells."

 

[shock]

So, just a follow up since I received lots of advice from those trying to help.

I took the lid off the septic tank, didn't smell all that bad actually. I wonder if the baking soda I put down there 2 weeks ago to balance the ph helped? Regardless, smell wasn't bad.

Before I took the lid off however, I did the smoke test, while I could smell the smoke bomb (had a distinctive smell when burning), I could not see any smoke coming from the lid or cleanout, just a smell nearby those locations.

So, took the lid off. No oil buildup on top. We're very careful not to dispose of oil into the drains. And then I took a wooden probe to test how deep the sludge was........nothing. Couldn't feel any sludge at the bottom, and no solids came up in the probe. Don't know if this is good or bad, but I assume the tank didn't need pumped in any case I take it, since no sludge.

I did notice a that the water (effluent?) level of the tank was about 6" below the inlet, and about 4" below the outlet pipe. I don't know if this is how they work, we hadn't been to the cabin in 2 weeks prior.

I put a gasket on the underside of the lid and replaced it.

So, we'll see if the gasket helps.....

 

[gstrom99]

I did notice a that the water (effluent?) level of the tank was about 6" below the inlet, and about 4" below the outlet pipe. I don't know if this is how they work, we hadn't been to the cabin in 2 weeks prior.

If the "water" level in the tank is below the outlet, sounds like the tank is leaking. The smell may well be coming up from the surrounding ground.

 

[shock]

If the "water" level in the tank is below the outlet, sounds like the tank is leaking. The smell may well be coming up from the surrounding ground.

That's what I didn't know, if the outlet had a leak. I couldn't see the outlet hole itself as it was a vertical pipe and that's all I could see.. I assumed there was then a 90 to go to the outlet.I have a hard time believing the tank has a crack or leak itself since they are pretty stout and there's no traffic around it. It possible, but improbable imo. I did gran the outlet pipe and try to wiggle it, to see if it was loose, but was on there pretty good.

I'll see if the smell returns. If it does, I'll dig down to the outlet pipe and see if anything is leaking around that.

I also thought about filling the tank up to the outlet pipe and then wait a day or 2 to see if it leaks down below it.

 

[ponytug]

So, just a follow up since I received lots of advice from those trying to help.

I took the lid off the septic tank, didn't smell all that bad actually. I wonder if the baking soda I put down there 2 weeks ago to balance the ph helped? Regardless, smell wasn't bad.

Before I took the lid off however, I did the smoke test, while I could smell the smoke bomb (had a distinctive smell when burning), I could not see any smoke coming from the lid or cleanout, just a smell nearby those locations.

So, took the lid off. No oil buildup on top. We're very careful not to dispose of oil into the drains. And then I took a wooden probe to test how deep the sludge was........nothing. Couldn't feel any sludge at the bottom, and no solids came up in the probe. Don't know if this is good or bad, but I assume the tank didn't need pumped in any case I take it, since no sludge.

I did notice a that the water (effluent?) level of the tank was about 6" below the inlet, and about 4" below the outlet pipe. I don't know if this is how they work, we hadn't been to the cabin in 2 weeks prior.

I put a gasket on the underside of the lid and replaced it.

So, we'll see if the gasket helps.....

Both the inlet and the outlet should be covered, and the only way they wouldn't be is if the tank has a leak.

So, congratulations on finding the problem, but as the level is below the inlet and outlet you are most likely looking at pumping the tank out, digging the tank up, and probably replacing it.

If you don't have one already, I would recommend adding an exit effluent filter on the tank to minimize any solids moving out of the tank into whatever your drainage is.

All the best,

Peter