Friday, June 01, 2007

Gory details

Our composting toilet is on the fritz. Its a home built system, not a commercial composting toilet, inspired by The Humanure Handbook, and this is the first major setback in five years. We've had little problems here and there that were relatively easy to resolve - smell issues, resolved by adding a ventilation fan, and fruit-fly issues that were taken care of by strictly regulating the disposal of fruit, and especially banana peels. This year the problem is the compost itself. Its not composting properly, which is resulting in the chamber filling up too quickly and a plague of houseflies.

Yuk.

Our composting system consists of two concrete chambers, filled from the top, each with an exterior clean-out hatch. Only one chamber is in use at a time. Basically, we fill side A, move the seat to side B, and while we're filling B, side A is merrily composting away. By the time B fills up and we have to shovel out the A side so we can use it again, it's compost, not poo. Just to be on the safe side, the compost is moved to an outside compost bin for a year or so before it's used on the garden.

Theoretically, with every poo wood shavings are added to the compost. Periodically I also add grass clippings and weeds to the chamber. The biodiversity seems to help the composting process. Usually it takes about nine months to fill one chamber. At some point in the process there's this almost magical effect where the in-use pile starts shrinking instead of growing, as the compost heats up, and then stabilizes. Its really wonderful, but it depends on a number of factors, and some of those factors fell apart this year in a way that is hindering the pile from getting hot.

The two big issues seem to be weather and pile management. I've been able to slack off on pile management in the past, when the weather has cooperated. This year its not cooperating. Its been dry, which has meant less mowing, and so less clippings to add. We also had a late frost, which I think really unbalanced the pile's ecosystem. It definately impacted the local insect population in general, and I think that's part of the reason we're having so many flies. They survived the frost better than some of their competitors and are now the dominent bug in the pile. Unfortunately, they aren't the best for making good compost.

The other factor that needs to be considered is Rayan - in terms of the compost, he comprises a significant increase in the quantitiy of poo added to the system without a corresponding increase in the amount of wood shavings. Figure that in with a decrease in the amount of clippings and you get a denser, and therefore less well aerated, pile.

I repeat: Yuk.

It has been less than six months since we switched chambers, and the in-use bin is almost full. That's unheard of! Especially with the outside temperature in the mid to upper 80s - it should be doing the magic trick by now. The pile should be going away. Its not. Its doing something weird and the flies are driving us nuts.

My temporary solution has been to return to the original humanure method ... the bucket. Sigh. I've set up a sketchy sort of outhouse at the back of the back yard and a compost bin for the bucket contents. I've "sealed" the chamber we were using and after just a couple days the fly population in the house has already noticably decreased. Whew. Since the summer looks like its going to be dry, I think we'll stick with the bucket system for awhile, until the usual time for me to empty the "composting" side, anyway. I'll fine tune things as necessary, but if you come to visit this summer, expect to use an outhouse of some kind. Its actually kind of pleasant to sit and listen to the birds instead of the ventilation fan.

4 comments:

Schuyler said...

I know you have a few other blogs, so I'm hoping you haven't been tagged on any of those. Come play!

Tag! The rules are here.
Enjoy!

meredith said...

Okay, I'm tagged.

OMG! I just realized I got through an entire post about my composting toilet without once using the expression "crapped out"! Apparantly I was so generally pooped that my sense of humor went down the toilet.

Okay, I feel better now.

Schuyler said...

And then you put all of the puns in your comment. Man, you are the sh*t, or as my childhood neighbors would say, the bomb (their nurse mom called poop BM's (what we called number 2s) which they translated into bombs).

Schuyler

Unknown said...

Hi meredith

Just browsing your blog. You know you can add a lot of other carbon-rich thinks to the compost as well as wood shavings. Chopped straw (made by sticking a weed whacker in a barrel of straw) is good. Shredded paper likewise.

Your place looks really nice. Wish we had a swimming hole...

Robert (pirateking)