Septic stink

bczoom · May 18, 2005

( The septic tank works by supporting anearobic bacteria to break down waste. It should not be vented.

The chemical reaction can be rendered ineffective by overloading the system with liquids or the addition of various household chemicals that can kill the bacteria. With no digestion raw sewage overflows into the secondary tank and into the drain system.

If this happens the field/mound area gets the raw sewage which is what you are smelling. /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif

Egon )

Egon,

Although I don't have vents, aren't they (vents) in the leach bed and not at the tank? Can/will they pump out nasty air when people flush toilets or use water due to displacement?

Woodlot,

Have you walked around on top of your leach bed? Any wet spots?

Brian

mwechtal · May 18, 2005

I've never seen anything that looks like a gasket on our septic tank lid. Of course, I've never gotten all that close when it was being pumped. /forums/images/graemlins/wink.gif The point is, if your lid is exposed, and doesn't have some type of gasket or seal I would expect to smell something bad. You can't really manufacture a precision seal in concrete.

I've also noticed that there seems to be some minor venting back through the house and out the nearest roof vent. Or it could be my imagination. /forums/images/graemlins/confused.gif

Mike

bczoom · May 18, 2005

( I've also noticed that there seems to be some minor venting back through the house and out the nearest roof vent. Or it could be my imagination. /forums/images/graemlins/confused.gif

Mike )

Mike,

Now that you mention it, my neighbor had a "stink" problem. His was due to the fact the vent pipe on top of the house wasn't quite tall enough and however the air was circulating around it, it was pulled toward the ground. He added a couple feet of pipe to get it over a nearby ridge on the roof and voila, no more stink.

Brian

Highbeam · May 18, 2005

You should not smell anything unless it's broken or unless you are too close to your roof vents.

Let me try. Any time any waste gets digested byproducts are formed like methane and other stinky sewer gasses. Totally normal. These gasses are vented by going back up the sewer line to the house and through the roof stacks to the atmosphere. You have traps on all of your inside sewer connections to make sure that these gasses do not come into your home. The lids of modern septic tanks are gasketed to prevent water from coming in and gasses from leaving. Any pipes on the drainfield lines are inspection ports and are meant to be sealed like the septic tank lids. No gasses vent out through the drainfield lines. The filter you speak of prevents solids from contaminating the drainfield.

Most of the time when a septic system stinks it is because the drainfield lines are being sent more effluent than they can release to the ground. This can happen for two reasons, 1) the system hasn't been pumped and the drainfield lines have been contaminated with solids making them unable to absorb the orignal amount of effluent. Your filter is meant to prevent this. 2) You are overloading the drainfield line(s) by either too much sewage going in or by faulty distribution to the lines meaning one line is taking too much of the effluent and the others too little. The tank pumper could not check for #2 because it happens downstream of the tank. Get it.... #2.

Locate the smell. Get your sniffer working and sniff around by the drainfield. Then sniff around by the exposed lid of the tank. Then finally, go up on the roof and sniff around near the stacks. Once you find the source, you can begin to fix it.

My guess is that part of your drainfield is overloaded and effluent is surfacing causing a stench.

You should smell nothing.

woodlot · May 18, 2005

Thanks highbeam. It could be the roof vents I suppose. I had not given that much thought. Next time I'm working downwind of the house and get that stench I'm going to try to work my way up-wind to the source. I suppose if there's no stink at the drainfield inspection ports or at the tank lid I could assume its the decomposing gases coming out the roof vents. I know when I've had to open up the DWV in the house there is a major wave of stink in those pipes! I can/will not be able to put my sniffer on the roof vent as the height and pitch of the roof scare me to death. I have never had any type of wet spot in the drainfield. My soil is sand. I don't mean sandy loom either, it offically known as "grayling sand."

When you say the concrete lid should be sealed do you mean a rubber or gasket type material? I do not have anthing like that. Just a ridge in the lid that slides in a valley in the tank extension.

Highbeam · May 18, 2005

The modern tanks use round plastic domed lids with neoprene gaskets like weatherstripping on a car door. The lids are fastened with stainless steel screws to the risers. If your concrete lid has a gas leak then it won't take long to make up a gasket of some sort. It could be as simple as a garage door gasket or mortaring the gap to make a tighter fit. I would shy away from a sealant or anything that would glue the lid on.

If you open the inspection port, and take a sniff .... it will stink. Not as bad as it does when you have the tank pumped but it will smell more like laundry water. I assume you intend to sniff check those ports with the lids on. With plumbing codes the way they are, the roof ventilation is not usually a problem.

Thank your lucky stars you are on sand. This is one of the few times that it is good thing. This fact makes me lean more towards an ill fitting lid on the tank. You could always bury it?

shvl73 · May 18, 2005

If it's the roof vent, try www.sweetair.com , I did, when I couldn't stand to sit out on my back deck, because of the odor. Now it's a problem solved.
Good luck,
Torin

woodlot · May 19, 2005

The more I think about it the more I'm suspecting the roof vents. I know that smoke from my wood stove pipe can come right down to the ground, if fact it happens often. It stands to reason that gases comming out of the roof vents do too. My house sits on the edge of a large field and the wind really swirls around.

My wife is always kidding me that I have to smell everything, she thinks is gross, she's going to have a good laugh when she sees me out there smelling all those pipes!

RobertN · May 19, 2005

We have a similar problem. Same results with pumping the tank too. We had odors, especially in the evening. We'd go out in our spa, and smell these odors. Most unpleasant way to enjoy the evening...

So, I dug in our summer hard as a rock clay, exposed the tank. They came out, looked, said it was working great. Drain field was looking good; no wet spots or anything. Pumped it anyway, since it was exposed and there was normal buildup.

The pump guy said it is common for the vents to emit odor, especially if the pipes are short where they come out of the roof. They carried charcol canister filters that go right on top of the vents to minimize the odors.

rswyan · May 19, 2005

( Most of the time when a septic system stinks it is because the drainfield lines are being sent more effluent than they can release to the ground. )

In some areas of the country this may be more problematic than others. In our area there is a layer of topsoil that can be anywhere from a couple of inches to over a foot thick. Below that there is fairly dense clay that's several feet thick and below that there is very heavy, hard clay that's probably pretty impervious to water. Our septic system is fairly modern (within the last 20 years or so) has two large tanks and a fairly sizable leach field (40' x 80'.) At the end of the leach field there is an outlet pipe at the surface for excess effluent. The area where this pipe exits got messed up by some contractors dumping debris from the construction of a deck and landscapers doing some grading - the outlet got buried and there was a shallow depression probably 10' x 40' that held effluent - very black water - a real mosquito pond. I've dug out the outlet and am in the process of regrading the area right now to get the excess to run off. With only my wife and I here, normally effluent will run out anytime there is waste water discharge from the house. Generally, standing right next to it I have not noticed any smell from this, but then I don't get down on my hands and knees and stick my nose right up to it either. /forums/images/graemlins/grin.gif

The neighbors are a different matter however - their homes and septic systems are older - 40 or more years. I think some of them may not even have leach fields. There are four homes that abut my property and all four's septics drain to the back of my property, behind our house - which, since the township installed a drainage ditch between a couple of said houses to carry storm runoff from the roads the neighbors houses are on, has become very wet, almost constantly. Might dry out by August. In the summer if the wind is blowing from the right direction you can smell it if you are out back - it ain't pleasant. /forums/images/graemlins/frown.gif