We are on a septic system and installed a garbage disposal when we moved in approx. five years ago. We are a lot more careful about what we put down it compared to our previous house, but still find that it is a necessity.

We originally had one that claimed to be for septic systems but it was noisy and quit on us a couple of months ago. We replaced it with a much quieter system and now just manually add the enzyme solution.

In my area you have to make a larger septic system if you plan on having one.

We're on a septic here as well. I've never entertained the idea of a GD because it's always been conventional wisdom but also because it just makes sense. It seems that it's just more solid waste going into that system. To me, that means it fills up faster and is more likely to bring failure of the system. There are other ways to dispose of that material (compost, conventional garbage, etc.) that just aren't an option for... Well, the stuff that goes into the septic system.
I will admit to letting a few coffee grounds that are stuck to the side of the filter go down the drain and into the septic though. This is a no-no too, but it's only a tiny bit - although every day I'm sure it adds up.
Remember, the people that make the GD's would love to expand their market into those with septic systems and your contractor doesn't have to pay to pump the septic system more often nor does he have to replace it if it prematurely fails.
I vote for no garbage disposal - your roses and other plants will thank you (for the coffee grounds, egg shells and other compost material).

Dean

I was just dealing with this issue as my new house has a septic system. Insinkerator has a GD for homes on a septic system, it is called Insinkerator Evolution Septic Assist. I went to buy one and the plumbing specialist told me that it is not really worth it, all I need to do is buy a regular disposal and once a month flush down the toilet some septic enzyme solution. All the GD does is inject some enzyme into the system every time you use it. The enzyme does not smell very good! I hope this helps.

My mother has had a garbage disposal with her septic system for forty years. She has never been particular about what she puts in it, has never had a problem with her septic and does not have a special disposal.

If you think about it, what goes in there gets chopped a whole lot smaller than any solids that get flushed down the toilet.

We have a septic with no drainfield (two tanks, aerator pump etc). We've had this septic system for 26 years and I use my garbage disposal like crazy. I've always had a 1hp disposal and even chop up chicken bones.
Never had a clog or a problem with the septic system. It's been pumped out once after 15 years, but I suppose that's to be expected.

We have a septic system and we have had 2 disposals since 1985! Nothing special. The new one is a Maytag. Whatever you put down it goes to the septic tank, breaks down and becomes liquid. We have never put any enzyme solution or anything down the toilets either. We do get our septic system pumped out about every 3 years, though. (preventative!) In the city close to us, you are not allowed to have a GD at all (city bylaw) as you cannot let it go down the sewers. I guess if you have a septic system and there was a problem then it would be your responsibility to fix it. If you get a GD I would advise you to read the book that comes with it as it will tell you what not to put down the GD. I remember mine saying not to put corn cobs, onion skins or bones in the GD.

Excellent - glad I asked. I like the idea of getting a good quality "regular" disposal, and manually adding the enzyme solution. We put in a new septic system about 10 years ago when we did our addition. We have it "pumped" every 2-3 years as a preventative measure and it's been good as gold. I really really miss my disposal from our old house. I'm not a gardener AT ALL, so I've got no real use for compost, and I truly do hate the smell of garbage in the house. I was careful with our old disposal, and I'll be careful with the new one. Thanks all - SQ

Working in the wastwater field I can honestly say that it is a bad idea. And people's experiences will vary with where they live and the soil conditions in their region. What works for one person's system for 20 years may not work for another. Composting is much better and good for your garden like Dean said! consider this, once your leachfield is clogged, you will need to replace the system. So if you are going to put in a GD, make sure you pump your septic tank regularly and don't wait 10 years or you could destroy your leachfield. We have a septic system that is failing (from previous owners) and are in the process of constructing a new one. We are lucky we have the land to put a replacement field on but if you live on a small lot, your leachfield may be your only one and if its destroyed, you'll be installing holding tanks which are a homeowners worst nightmare!

Hope that helps! Not trying to scare you this is just something I know a lot about.

Good luck!

We built our house in 1993 and have had a regular garbage disposal for the entire time. I have a regular plain old septic system with a leach field. The only thing I do not put down my drains is cooking oil. We have only had it pumped out once.