Thursday, 31 May 2012

What's your view of the composting loo? Can you deal with your own poo?

Trev and I like to say we can deal with our own shit. But strictly not true as it's Trev's job to clean out the dunny.  I maintain a discreet distance while pointing out what fruit trees I want it planted under.  Caleb loves the new house, but is embarrassed when his friends come to stay and we have to introduce them to the loo. He doesn't like the toilet.

We have a Enviro-let. A self contained unit that heats and mixes our ordure in order to turn it into usable compost. Building codes meant we had to build a small hatch in the side of the wall to pass the tray of compost through so as not to walk it through the house. It's supposed to be every three months according to the manufacturers specs. But in reality it's more frequent that that.  When  you sit on the seat two plastic leaves slide to the side and you do your biz. When you get off, they close. We also use a small fitted lid that sits above the leaves to reduce any possibility of smell. It's not normally smelly.

We don't like this toilet much either. It is our single biggest power user in the entire house. We used it in our old shed because we were able to buy it secondhand (hey, we can deal with other people's shit too) and it was only going to be temporary till we found a better option. We haven't yet, and the council only has a few options it has given the tick of approval to.

We had a Nature-loo in QLD, it was great. It was a porcelain bowl with a wooden seat, it looked quite normal till you lifted the seat and where the porcelain ended a black chute began. No s-bend. Basically it was a glorified long drop with an exhaust fan, it extracted the wiff through a roof top vent and was typically odourless. That was unless the power went out and then we wrapped a especially bought gladwrap roll around it till the power resumed. At the bottom of the house we had two large black Dalek shaped and sized plastic containers where the poo was stored. The wee is drained off, in this case into an otherwise un-used and pre-existing septic tank. The trouble was that whenever you wanted to exchange the Dalek's they were enormously heavy. It was our only grizzle. We needed a trolley system to reduce the weight.

Amazingly when our poo is composted, our annual 'yield' weighs in at an average of 25kg. The thing that really bothers me is that the average Australian uses 16,000 litres of potable water to flush away that 25kg of waste per year. Then we spend a lot of money and resources trying to treat it. It never becomes an asset. It is treated anaerobically not aerobically, which means it forms toxins instead. It's like the big doh! of civilisation.

Here's an excerpt from Living the Good Life on using it in the garden.

The gardener’s reward

The raw material is broken down by micro-organisms, and thermophilic action (heat), which kills pathogens and viruses, and the length of time itself renders most possible vectors for disease harmless. As the composting system is aerobic, microbes, which require an oxygenated environment, are able to break down the compost into a useful plant food. The humus is covered in pores, which shelter nutrients, water and air more than soil can, and it releases nutrients gradually as it breaks down.

When emptying a composting toilet the ‘humanure’ is required, by law, to be buried. To be on the safe side, it should not be used on vegetable beds, but buried under a tree and covered in mulch.

In many less squeamish cultures, humanure is a useful source of topsoil on food crops. In the past Japanese farmers would vie for travellers’ excrement by building comfortable roadside privies and, once it was composted, they would use the deposits to enrich their soil.

According to composting toilet manufacturers, installing composting toilets in households is a slow-growing trend. Stuart Elliot of Nature Loo wonders ‘why the government doesn’t recognise the benefits of composting toilets and provide incentives to people who install them’.

As John Foss of the Surfrider Foundation (Surf Coast) says, ‘Recycling human and industrial waste is the only way that Australia can manage sustainable population and agricultural and industrial growth into the future’.

Any way you look at it, it’s time we got our shit together.
What about you? How do you feel about composting loo's and seeing your own poo's?

Photo is of the loofah's we used instead of loo paper. Still would if only I could get it to grow successfully here. I'll keep trying.


dweeze (Johnno) said...

Linda, I was just on the phone dealing with our council on exactly what kind of excrement treatment system they will sign off on when I saw this *very timely* post of yours. We were looking at a worm farm system but have been scared off by cost and vendor attitude. Septic is the (initially) cheaper option but I'm with you on the aerobic / anaerobic dilemna.

Re your question above: throwing out a potentially useful resource becuse we cant stand to take responsibility for the wastes that we all create is madness. We all shit (I'm full of it) - why not use it? Of course, within healthy parameters...

Anonymous said...

Thanks for sharing your experiences. We are considering the envirolet vacume flush system for when we build our house. Do you have any thoughts on this? Or could you list some of he other models that you have been looking at?

Anonymous said...

Most likely considering a reed bed system when rebuild. Currently we have a very old septic system, which we flush with bore water so the rain water is saved for everything else.

Hubby works in the sewerage industry and they are actually beginning to do some interesting things with our poo. I know he has talked about reed beds being used on a large scale, along with using carp to clean up the water. These carp are then used to for pet food.

Kristy @SeeMyFootprints said...

I have looked the ones on Milkwood
and was quite impressed. I like the idea of the wheelie bin ones...
the chances of us getting a composting toilet of any sort at this house (design issues) and with this council would be pretty hard but it's on my 'wishlist' for when we one day build.

Anonymous said...

Hi Linda,

I have a RotaLoo and quite happy with it. 13 years old now. There are 6 wedge-shaped bins on a rotating table. When the first bin is full you rotate it manually to the left and Bin 2 comes into use, and so on. The time it takes for Bin 1 to get back to the beginning depends on how long it takes to fill a bin. When my husband was alive it took us a month to fill a bin, so each filled bin spent 6 months on the merry-go-round, during which time it composts and is pretty much unrecognisable at the end. Now it takes me about 6 weeks on my own to fill a bin.

There's an exhaust fan which takes away any odours. I don't think it uses much power and mostly there's no odour if each deposit is covered (I use wood shavings, which I buy, but could also use mulched bracken which grows here).

The liquid goes through the solids into the base of the chamber and it supposed to evaporate off (aided by the fan) leaving a residue of uric acid (or whatever dried wee becomes). You're supposed to flush this out with water every so often. I drilled a small hole in the base of the unit and attached a 5mm plastic tube, and run off the liquid each week, store it in a plastic bin (in full sun) and dilute it for the fruit trees.

When I empty a bin I put it in a separate compost heap and add a tray of worms from the worm farm. They go through it and at the end it's black, friable and beautiful! I use it on any food crops, even veggies!

We investigated the NatureLoo but didn't like the idea of the large bins having to be heaved around. You've reinforced our decision not to get one.

Linda Cockburn said...

Hi Anonymous,
I have no personal experience of this system, perhaps someone else does? Looks like there will be a few personal stories of personal systems coming through. foodnstuff's system sounds great. Not enough room under the house for us though.

sharon said...

I like the simple sawdust toilet, as in the "humanure handbook". Personally I rekon its the most effective but its not legal in our area at least. Its basically what Milkwood Permaculture use. Our council has made it so hard for us, more so with how to treat the greywater - what system have you put in for your greywater. we had a permit for a reedbed system for our (greywater) but now they have refused it (the joy of taking too long to get it all done and having to renew permits). Oh, how I hate dealing with them....

Linda Cockburn said...

As we only have grey water to deal with, and no black water we were able to, (in conjunction with the right soil type) to have just over 45 metres of sub-surface area to drain our grey water into. We use about 200 litres of water a day - as a family (much more than we used in QLD - mostly because we can). So far this has worked very well, it has two filtration systems on it before it goes into the ground which is a series of trenches with drainage rocks laid into them, then the non-pvc piles, then geotextile laid over top of them and then soil. Our only grizzle is that we couldn't afford to treat the water and re-use it.

Beznarf27 said...

I totally agree with you about composting loos. I am almost tempted to build one myself out the back from plans that I downloaded. We all use so much potable water and in a place like Australia where water is precious and only becomming scarcer and our soil is naturally ancient and thin we should be making the most of our water AND our potential soil ameliorations and minimising our reliance on government departments to do it for us. Cheers for the great post

sharon said...

Linda, so your system is not a EPA approved system as such, with an approval number etc? Our original permit had a reed bed with absorbtion trenches etc, but it was just designed for our use, it wasn't an 'off the shelf' greywater system. But now they have said we need to choose a system off the EPA site (so an off the shelf, pumps and maintenance contracts type thing).... grrr, its just greywater, and we want to deal with our waste water on site, without having to pump it out etc every year (which is what our council would like!)

Terry said...

Hi Linda, We have a Clivus Multrum which is similar to your Qld. toot. All's well until the power goes out, or if you're solar only, when the fan goes kapoot. We found the Jayc%r fan to be half price of "genuine" one and quicker to get... Yeh I'm over the "seeing the poo" thing. For mine, having positive ventilation makes a compost loo bathroom smell better than any other. I use ours on the veg too just quietly. The Chinese used to compete to get fresh poo for their veggies. I think money changed hands as well. All good. Terry