I’m looking for feedback on the pros and cons of using garbage disposals in homes with septic tanks. I know this is a controversial subject, or at least it used to be, and I’m wondering if the general concensus of not using disposals with septic systems still holds. I see that at least one manufacturer makes a garbage disposal that is designed specifically to be compatible (for lack of a better word) with septic systems. Anyone familiar with these?
Jim
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Replies
What does it do? Masticate the leftovers, add enzymes and bacteria, and hold it for twenty four hours to work? Oooops - that's my gut.
The reason disposals are hard on systems is that they add a lot of solids to a system designed to handle fluids. The more solids added to the tank, the less capacity it has to handle the fluids. Sure, the tank is intended to be a place for solids to settle out while the bacteria digest them into a fluid state but to build it big enough for constant careless use of a kitchen pig, you'd need a system two or three times the size.
In many places, where a kitchen pig is instaled they recommend or require the adition of a grease trap box to the line to be dug and cleaned every year. An alternative would be to pump your tank twice a year.
Take care of your system and it will take care of you. Abuse it and it will abuse you. I know a guy who has a system designed for three bedrooms - 270 gallons a day. He has three daughters and a wife and he's the kind of guy who never takes care of anything. He put in a pig to add to all that toilet paper and after only four years, guess what?
$22,000 for a new system.
It's your money...
Excellence is its own reward!
Piffin's right. I've been a country boy my entire life, make an effort to keep grease and other solids out of my system and by doing so, it really has never needed pumping in 16 years, although I was required to have it pumped when I hooked up to my new house.
And most of the stuff people poke through a disposal is a problem for septic systems, but is great compost material.
An elderly fellow I've known for a long time has a disposal grinder set up in a sink in his garden shed so the stuff from his kitchen (non-animal waste, of course) feeds the worms and eventually, his garden.
But, you asked for pros and cons and I can't think of any pros. Sorry.
we have had garbage disposal all our lives, with septic systems. Never been pump. thirty years old. I think is more what you put in than the garbage disposal it self
You're scaring me Brownbagg- 30 years without a pump out ? I think five is max for any system that gets used.
We had a garbage disposal with a bio cartridge that you had to replace once a quarter on our system for about 16 years with no problems.
Just don't build any structures over your drain field.
I did , crushed the pipe, and it cost me $30,000 to hook up to sewer. Bob
"Rather be a hammer than a nail"
I moved into my first rural home 2 years ago. The prior owner pointed to the greenest spot out front when asked where the septic was. It took me over a day to findly find the tank. It had not been pumped in thirty years. A little stream of sewage ran between the inlet and the outlet on top and between the packed solids. I pumped it out that week and built an access to the tank.
If you have a septic then you have room for a compost pile.
joe d
It sounds like you bought Brownbaggs old house.
Excellence is its own reward!
"The first rule is to keep an untroubled spirit. The second is to look things in the face and know them for what they are." --Marcus Aurelius
Bob, my system down the road in Renton has been in use for 31 years, never pumped(No disposal, self designed and installed 1971, 1200 gal, 300 ft of line, all gravity with weir outlet distribution box) . I did shovel all the toilet paper off the top of the liquid once a few years ago (91?) just before the new county regs on "can't dump it in your yard" went into effect (garden really did great that year). Checked it 2 years ago and there is only 3" of sludge in the first compartment, the second is still all liquid. Beats the heck out of $40/month sewer bill, etc.
Accidentally cut thru a field line this sumer putting in a power feeder - clean, asolutely no scum or grease in the field.
Concur with no disposal recommendations. County regs here actually prohibit grease traps.
In Oregon, septic material is now considered "hazardous waste" and, consequently, the pumping fee is about $350-$400 for a 1500 gal. tank. About 15 years ago, it only cost about $50 (to cover truck and driver).
"You're scaring me Brownbagg- 30 years without a pump
out ? I think five is max for any system that gets used."
My experience is that "pump outs" are required only for abused, poorly setup or under sized systems. Mine, too, is 30 plus years old, never been pumped, never needed to be pumped.
Go to - http://swopnet.com/geo_wastewater_2000/machmeier_care_n_feed.html or any other septic website. As a rule septic tanks should be pumped every 1-3 years for 1000 gal tank serving 3 bedroom home w/ 4 occupants w/ no garbage disposal. I really don't care if you guys ever pump your tanks, I am just stating the norm for most systems.Bob
"Rather be a hammer than a nail"
My family house is in a rural subdivion on 1 acre lots. They is about 200 houses in that sub. The soil are a very sandy loam, no clay, no swelling clay. Our house was built in 1972. It has never been pump, aint never had any problems with it. I can only remember two houses in the neighborhood ever having to be pumped. Maybe we are just in good soil. Oh and there is not a single tree in the sub,
Thanks for the info. I will certainly look into it. I do learn something new almost every day I get out of bed!
We all do Tim- I just showed my 85 year old mother how to test an AA battery (with the built in tester on the side of the battery, she said "oh my I didn't know that?" I said " Mom, you're never too old to learn new tricks" :-)
Bob
"Rather be a hammer than a nail"
Not worth pumping now, getting 30 years of solids out would be nearly impossible. Cheaper to put in a new system. On average (in my experience) in a 1500 gallon tank with no disposal 3/4" of solids will collect per person per year.
Also FWIW when pumping a tank it should only be done through the tank access and not the inspection pipe.
Why should it only be done thru the tank access and not the inspection pipe? Let the thunder crack and the waves roar.
We're going on.
Tank needs to be scraped , rid of any tree roots and inspected. It's very difficult to tell a failing drainfield through the inspection pipe but easy through the access.
If backflushed through the inspection pipe this can dislodge large clumps of sludge and if they hit and break a baffle your SOL (pun intended).
It's unacceptable by code here, although I do see some put in after the CO inspection. I'd personally not do it if I had an alternative septic system, like pump or irrigation, infiltration, etc.
I lived in a house for 15 years that never had the tank for more than 40 years...single terra cotta line,too.
But then, we flush potato peels down our toilet every so often, read about it in Mother Earth News about 50 years ago, worked in every house I've ever lived in...
"a full house beats a house full of flushes" Bob Dylan It's okay, I can fix it!
We're on a septic system and have a disposal. I wouldn't do this in a house for another buyer, but the three of us living here know the drill ... the disposal is there only to clear the small and occasional thing that gets washed down the drain, not to regularly scrape the plates into. Working that way, we had the tank pumped recently after 7 years of use ... not bad. I like the idea of not having to deal with crap plugging up the drain line.
Side note: put a teaspoon of yeast a month down the drain, or the toilet, or whatever. Wotks great to grow the beneficial cooties you need in your system to digest the solids.
The problem you have with most waste put through a disposal is that is mostly comprised of vegetable rinds. They take a long time to decompose and they float. Which means they can get into your field and plug it up. One of the DIY magazines I subscribe to did a piece on disposals and septics. They found a water powered disposal that absolutely pulverized the garbage. In this state the rinds would sink and their decomposition was accelerated. I'm building a place with a septic, no disposal for me either. The wife is used to using a strainer in the sink at her mothers cottage.
Here's a comparison. My grandparents built their house 30 years ago, almost perfect soils for a septic. Tank has been pumped about every 5-7 yr. They've been using a disposal since day one, my grandma had to have the entire field replaced last year.
My house 150 yrs. Old septic age unknown (no record with the county) but tank is very small by today's standards for a four-bed house. I'm on loamy clay. No disposal and septic still working good.
I'm sure there is a lot more to consider for the septic failure at grandma's house. However the disposal is certainly something to consider.
Scott R.
Edited 11/5/2002 11:23:12 AM ET by Scott R.