Septic Systems 101
June 6, 2011 8:01 AM   Subscribe

Please tell me what you know about maintaining septic systems.

My husband and I are about to move to a somewhat rural area (in Maryland if that matters) where most of the houses have septic systems. I have never lived somewhere that has one and have no idea what is involved with maintaining one. We will be renting at first, so I'm assuming that the landlord will be doing the major maintenance, but I don't even know what to ask them about it.

Are there differences on what you can put down the garbage disposal? What about cleaning products? Are there things we can do to keep the system "healthy"? What should we be expecting the landlords to do as far as maintenance? Anything else we should be aware of?
posted by Kimberly to Home & Garden (25 answers total) 10 users marked this as a favorite
 
Never put drain cleaner down the pipes. You'll kill all the helpful bacteria working-away in the tank. Flushing bulky stuff is a no-no, too. Like tampons. No flushing tampons.
posted by Thorzdad at 8:05 AM on June 6, 2011


This book is a terrific introduction to the topic and totally an enjoyable read. I grew up my whole life with a septic system and really didn't pay that much attention to maintenance. We had a garbage disposal even though that's supposedly a no-no. You can get toilet paper that is more "septic friendly" and flush probiotic stuff once in a while but a well-maintained system should have very little need for you to do anything special.
posted by jessamyn at 8:13 AM on June 6, 2011


No drain cleaner.

No chlorine bleach if you can help it, especially in the winter. Use oxygen bleaches (aka oxyclean) instead.

No condoms down the toilet.

NO NO NO rice down the garbage disposal (this was one of my more expensive mistakes).

Rid-X or other so-called "septic treatments" are a total waste of money.

It's going to have to be pumped every 3-5 years, depending on the size of the tank, the number of people using it, and the age of the drainfield - make sure it's clear in your lease who is responsible for having this done, as neglecting to do it can result in backups into your house.

Speaking of pumping, find out where the tank is located, and don't plant anything on the ground above it that you care about - it'll have to be dug up to pump, unless they've had a ground-level cover installed that's wide enough to get a pumper hose down.
posted by deadmessenger at 8:15 AM on June 6, 2011


Oh, and no oil/grease/etc down the disposal, either.
posted by deadmessenger at 8:16 AM on June 6, 2011


...find out where the tank is located, and don't plant anything on the ground above it that you care about...
Following-on to that, you should also not plant any large or deep-root plants in the area of the finger system/leech field. Roots will destroy a finger system. I'm sure your landlord can fill you in on what you can and cannot do.
posted by Thorzdad at 8:19 AM on June 6, 2011


Look at municipal laws (if there are) about the frequency at which the tank needs to be pumped (here we have to get it done every 2 years no matter how filled it is). While you're there, ask for all documentation pertaining to the specific house and land you'd like to buy (conformity or non-conformity certificates for the installation and/or subsequent modifications, earlier issues that were raised by the city, etc.).

It will also tell you how old the system is (depending on where you are and how the system was maintained, it could last anywhere from 20 to 40 years, but again, there might be municipal laws about that), and how many "rooms" it was designed for. Sometimes very old installations will be made out of wood, and may be "legal" as long as you don't do anything to modify them--at that point you need to bring the whole thing up to current regulations.

Don't drive or park anything heavy on the field where the perforated pipes run. Don't leave the grass too long. If there is a pump that gets the water out of the tank, check its installation date, and get a second, back-up pump.

Other than that there's not much to worry about. Don't buy the 'enzymes' that supposedly help your system be more efficient--I've seen a system ruined after using them for an extended period.
posted by ddaavviidd at 8:36 AM on June 6, 2011


I grew up in a house with a septic field, and have one now. It's not hard, and it's mostly common sense. (much of this applies to people on city sewers, anyway -- the only real difference between a city sewer plant and a septic field is size....)
  • No grease/butter/oil/paint/etc down the drains.
  • No paper other than toilet paper down the toilets (no tampons or diapers). (Don't panic if some falls in, but don't make a habit of it.) And yes, this really does include facial tissue -- if you're in the habit of flushing tissues after you've blown your nose, break it.
  • Don't use great wads of toilet paper.
  • Don't put plastic down the toilet (eg condoms).
  • Unless you've got a radically undersized septic system, it probably isn't necessary to use "septic friendly" TP. well, other than don't use the stuff with lotion in it.
  • Take it easy on the rinse out conditioners for hair and laundry.
  • Avoid chlorine bleach as much as possible.
  • If the tank is big enough, or it's a double tank, a garbage disposal is OK, but use it as little as possible.
  • Find out who's responsible for getting the tank pumped -- a properly sized field in good repair shouldn't need to be pumped more than every decade or so, but you'll want to have it checked before you move in. (and, as ddaavviidd notes, some municipalities specify how often it needs to be done.)
  • Don't plant anything over the tank(s) -- it gets warm there, and anything you plant will get dried out (yes, even grass).
  • Find out where the drain field is, and don't drive over it. Don't plant trees there, either. And you'll probably have to mow more often there.
  • skip the enzymes -- you really shouldn't need them, and if you do, your system has other problems.

posted by jlkr at 8:47 AM on June 6, 2011 [1 favorite]


I never had a septic before I bought my home and was a little anxious about it. I agree with not flushing the obvious big things mentioned above. Also, I get it pumped every 3 years (even though the guy said I can go longer) because its only a few hundred dollars and I look at it like insurance. I like that someone opens it and takes a look to spot any problems. I disagree with with not putting in probiotic treatments. Yes IDEALLY you would never use bleach or drain uncloggers or cleaning products but you eventually do. You use antibiotic hand soap or dishwashing liquid? So for a few bucks a month you can help your system stay healthy. I just flush one packet or treatment every couple of months to get some "good" bacteria in there. Also the guy who owned the house before me was in wastewater management and suggested that. YMMV.
posted by Busmick at 9:19 AM on June 6, 2011 [1 favorite]


No real knowledge on the subject, but a maintenance man once told my father that the clogs we experienced in our family's septic system were the direct result of our failure to "chew [our] goddamn food properly."
posted by broadway bill at 9:52 AM on June 6, 2011 [2 favorites]


Use strainers in the kitchen sink to cut down on the stuff that goes down the drain.

Use liquid soap for the washing machine and dishwasher instead of powdered.
posted by luckynerd at 10:02 AM on June 6, 2011


I grew up with septic and we never used any of the probiotic treatments or anything. Before they came out though, I had heard of people intentionally pouring yogurt / spoiled milk / etc. down the drain rather than throwing it out because it's "good for the septic." I have no idea if that is true, although it makes a certain kind of sense.

The only difference between septic and city sewer, in my experience, is that with a septic system you need to have the 'sludge' pumped every few years. (My family does it every 5 years or so, maybe less often, but maybe the tank is unusually large.) Make sure you know where the pumpout cover is. Some people put a brick or potted plant or something else on top of it, so they remember it. (If you don't know where it is, and you're in a snowy area, wait until winter and the first light snow. The tank will probably melt the snow overtop of it.)

We never had garbage disposals and it was always 'common knowledge' in my town that you "can't have a disposal on a septic system." I don't know how much truth there is to this, but nobody really questioned it that I know of. (We had a compost pile anyway.) I have seen disposals sold in stores which claim to be 'septic friendly' and have tanks of blue goo that they inject along with the ground-up food, but I wouldn't trust them.

And of course nothing but toilet paper and waste down the drains. That should really be the rule for city sewer as well, because the other stuff causes problems down the line, but with a septic system it's your problem if you flush a condom or whatever down there. Same thing if you pour paint or other toxins down, especially if you have well water. Nothing quite makes you think twice about pouring something down the drain than the thought that you may be drinking it eventually.
posted by Kadin2048 at 10:10 AM on June 6, 2011


Before you buy, have an inspection done -- you absolutely do want to do this, and it may be required anyway if you are getting a mortgage -- and ask loads of questions. Find a septic-tank-engineer who is friendly and chatty on the phone and look forward to that person showing up, digging up your yard, and then answering all your questions and drawing interesting little diagrams for you and so on.

I, er, break many of the "rules" above with (so far) no unfortunate consequences. The CMHC says "Household disinfectants such as laundry bleach or toilet bowl cleaner can be used in moderation without affecting the operation of the septic system; however, overuse of disinfectants can kill the bacteria in a septic tank" here, also, "You should avoid putting anything into the septic system that doesn’t break down naturally or anything that takes a long time to break down."

I would not freak out over a little butter going down there; I don't dump my deep fryer's oil down there, but a bit is fine. You do after all poo out a certain amount of grease.
posted by kmennie at 10:25 AM on June 6, 2011


Thorzdad writes "Like tampons. No flushing tampons."

Tampons shouldn't be flushed down city sewer systems either. Neither should condoms.
posted by Mitheral at 10:48 AM on June 6, 2011


On septic here. In our area, it is rare to have a disposal when you're on septic.

Besides all the other good advice listed above, be careful about cat litter. I can't remember if it's the clumping or clay style (or possibly both?) that could clog things up, so to be safe, I am careful about wiping out any litter crumbs before I wash the boxes in the utility tub. Also, never flush clumps.

One thing that I learned about our septic field is that occasionally I will walk across that part of the yard, and the bottoms of my shoes will get brown. I don't know exactly what causes this. It's not plain poop bubbling up, since there is no odor. Maybe the dirt is just extra ... brown. ::shrug::

If you're on septic, you probably also have a well, since they seem to go hand in hand. You'll want to taste the water. It will be potable, but it might not taste all that great. If you don't think you can stand drinking it, you'll want to get either a filter (at the faucet), or a water cooler (or both). You might have a water softener somewhere (ours is in the basement). Ask about that, because it's another thing you'll have to worry about maintaining, and you'll probably have to replace the salt in the softener periodically.
posted by SuperSquirrel at 10:52 AM on June 6, 2011 [1 favorite]


The husband here.

Thanks for all of the advice and anecdotes. Does anyone out there rent with a septic tank? Is it common practice for the landlord/property owner to pay for the regular servicing and maintenance? Or are you, as the filler of the tank, responsible?
posted by Jim T at 3:08 PM on June 6, 2011


In addition to all of the aforementioned tips:

Buy the thinnest generic light-weight single-ply tissue you can find. You know, the stuff that you can practically see daylight through, it's so translucent. If it begins dissolving after a few minutes in the bowl, you've made the right purchase.

Also, switch to a diet high in roughage. I can hear you laughing in the background, but I'm dead serious.
posted by Gordion Knott at 3:53 PM on June 6, 2011


So everyone's pretty much got it all covered. What I can add is a simple description of what's going on inside the septic, so you can get it from first principles.

All the wastes go into a large holding tank. This is going to be very liquid, with all your shower water and whatnot. Anaerobic digestion processes will separate the wastes into three layers. The bottom layer is the sludge, that's the solids that can't be digested. It will slowly slowly fill up, and when it gets full (depending on the size of your system, typically three to five years) that's what has to get pumped out.

The top layer is the scum. Fats and oils and things that the septic has problems with. Don't put fats and oils in your septic, they make it crook. They will break down slowly though.

The middle layer is watery, in fact it's mostly water. The outlet to the drainage lines is from this section. If flows (sometimes is pumped electrically) to absorption lines that are slotted pipes a few feet down in a gravel or sand bed. Further natural decomposition and leaching happens here.

You need a healthy system, so no nasty bleaches or strong chemicals please. Try to limit the total amount of water into your system, use low flow shower heads, a front-load washing machine etc. Putting food scraps down the drain isn't terrible, it'll just fill it up too quickly.

The drainage lines can't be filled up with roots, so no trees there. Our absorption lines cost $5000 to replace because the previous owner thought some silver birches would be pretty there. And vegies aren't supposed to be grown either, though I think that's overcautious, people have been directly applying crap to soil for millennia.

You know when the septic is full when it starts to smell. Pretty simple. Although we've got a permit condition on ours that it has to be pumped every three years no matter what.

I have no idea what the situation is re landlords. My natural inclination is that it is the landlords responsibility not the renters, because this isn't an annual thing and why would a renter have to pump other peoples poo?

Our septic pumper required us to uncover the hole, about 50 cm down. Spade time!
posted by wilful at 4:27 PM on June 6, 2011 [1 favorite]


Also, switch to a diet high in roughage. I can hear you laughing in the background, but I'm dead serious.

yep, that's me laughing.

Don't be scared by a septic, it really doesn't require any major lifestyle changes. You don't need anything more than basic common sense. Do not change your diet, do not worry about special toilet paper.

Maybe this might be the case if you have a very old, very small septic system. In which case, it's probably best that it get replaced.

I'm sure municipal water authorities would be very happy if people on sewerage systems treated their waste pipes like they're septics.
posted by wilful at 4:30 PM on June 6, 2011


I've rented several apartments (and a house) that needed a septic tank. It was always the owners' responsibility. If they were connected to the city system, then they would be paying taxes accordingly, not you.
posted by ddaavviidd at 5:40 PM on June 6, 2011


I don't have a septic, but our building does have a grease trap for the kitchen line. Once I got sick of it clogging up because people could not stop dumping grease down their sinks, I started putting some of that biological grease destroyer stuff (one of those Ace Hardware kinds of things), it hasn't needed to be pumped out.

If I owned a septic, I'd be dumping that stuff down on a regular basis. Besides the septic tank itself, that stuff keeps the pipes squeaky clean.
posted by gjc at 7:05 PM on June 6, 2011


What do you do with your paintbrushes if you can't wash them out?

I recently bought a house with a septic system (which, growing up in the Midwest, was something I only knew as an aspect of farm living), and I have to repaint all the rooms. I already found a friendly septic guy who seems to know everyone in town; he explained a lot of things to me while he pumped out the tank last Fall. But no one mentioned not rinsing out my paintbrushes!!!
posted by wenestvedt at 6:25 AM on June 7, 2011


I've rinsed out paintbrushes into my septic system plenty of times. Did your septic guy tell you this was bad? Eek. I hope not.
posted by SuperSquirrel at 7:30 AM on June 7, 2011


It's pretty much OK to rinse *LATEX* paint off of brushes/rollers (in moderation), but don't pour straight paint down the drain.

Oil paint or thinner? Rinse brushes/rollers in a bucket in the garage and dispose of it properly.
posted by jlkr at 1:12 PM on June 7, 2011 [1 favorite]


What do you do with your paintbrushes if you can't wash them out?

If it's latex based paint, you wash them out in a bucket, and then if there's a lot of paint in the bucket you pour it through a towel/rag on its way down the drain, and throw out the crap in the rag. You probably don't need to do this unless you are doing a lot of painting, though.

Actual waste paint you should let dry out and then throw away, not dump.

If it's oil based paint, you shouldn't be dumping the thinner down the drain anyway. There's a special place in Hell for people who do that. Also, it's expensive and if you let it sit alone for long enough, the paint particles fall to the bottom and you can pour off the thinner and re-use it for cleaning brushes again (but not actually thinning paint).
posted by Kadin2048 at 3:56 PM on June 7, 2011 [1 favorite]


If you plan on buying the house and/or adding on to it, make sure you're not restricted to what size house you can build. Here in Massachusetts I'm on a septic system that is rather close to the wells we get our water from. Because of this, our lot size limits our septic system to one for a two bedroom home. So when we built our house it was limited to two bedrooms. We can have as many bathrooms as we want, but only two bedrooms for now. Fine for us, since we plan on staying, but some day it will hurt our resale value. There are alternative systems that use pumps and whatnot, but they are expensive and somewhat unproven.

It may not be a problem where you live, but call your local board of health, or whomever oversees such things, to see if there are any restrictions before you buy anything with a septic.

Other than that, I grew up with one and have one now and there's nothing to it other than what's been said above.
posted by bondcliff at 6:34 PM on June 7, 2011


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