Dog poo experiments

My inspiration - Dr Andrew Agnew

My inspiration – Dr Andrew Agnew

One of my lecturers at university, the person who inspired me to become an ecologist, was Dr ADQ Agnew. He was (and still is) the epitome of a dotty professor… one day he came in to the department wearing two ties because he’d forgotten that he’d put one on and so he donned a second before leaving the house. He would sing to us in lectures (I particularly remember a rendition of ‘I’m a Gnu‘) and deliver anecdotes… he even took us on a field trip to the Low Countries (Holland, Belgium, Luxembourg, France and a bit of Germany) that involved him and seven female students all in their early 20s… which probably wouldn’t be allowed these days! Anyway, Andrew often claimed to have studied the effects of population density by examining dog turd predation by lawnmowers in a park… I can find no published paper on this subject (and, believe me, I’ve looked), but it may exist somewhere. I might ask him about it next time I see him.

Max - a source of pollution

Max – a source of pollution

My experimentation, in contrast, has a rather more practical bias. One of the waste products that we have to deal with on a daily basis is, indeed, from our dogs, Sam and Max. They are terriers, so there isn’t a huge volume, but even so it is something that we do not feel happy about sending to landfill.

It is easy enough these days to buy plastic ‘poop’ bags that are biodegradable and simply to throw these away with all the rest of the trash. I wondered whether it might be possible, however, to collect the dog poo this way and then just place the entire bundle on a compost heap to break down. However, some trials revealed that even after a year, the bags were still identifiable, although the content had often disappeared. Anyway, whilst trying to reduce our impact on the environment, it seems inappropriate to ‘consume’ plastic bags in this way.

What we wanted was a composting system that was contained (to avoid flies and smells) and that was separate from our standard composing bins, so that the end product could be used separately. It’s generally recommended that you don’t use humanure on food crops and I assume that the same goes for doganure (ooh look, another new word!). However, whilst I don’t want to apply it to salad crops, for instance, I see no problems with using this type of compost when planting fruit trees and bushes, or in a bean trench.

I have written in the past about my wormery, but I have become increasingly aware that I don’t really need one except for the liquid feed: pretty much all the compostable material we produce can go on a ‘normal’ compost heap and with the aid of grass clippings, we manage to get these hot enough to break down quite quickly. In addition, I’m an increasing fan of in situ composting… so that the heat generated can be utilised by growing plants. So, the wormery has become superfluous and, thus, available for use in the composting of dog waste.

Some limited research suggested that dog waste is acidic (I haven’t tested this, but perhaps I will once I can work out the best way to sterilise my pH meter afterwards) and that some means of raising the pH would be appropriate. One of the suggestions was that adding wood ash would work – something that we produce from our Kelly Kettle and that we normally add to the compost or put straight on the garden. I was inspired by Deano’s approach to this problem at the Sustainable Small Holding, but decided to use shredded paper for some bulk rather than the Miscanthus that he has access to. We collect the faeces in a bucket round the garden, but when we are out on a walk, they are picked up in paper and transported in a plastic bag before being added to the bin, complete with the paper wrapping as an additional source of carbon.

Initially, I only added the three dry ‘ingredients’: faeces, ash and paper. But Deano’s suggestion to add urine as well seems to have been well-founded: a recent agitation of the content of the bin revealed that it was very dry and did not seem to be very active, although there was no unpleasant smell. In addition, there was no sign of the worms that I had added. So, with this in mind, I have been adding urine for the past couple of weeks, now that I have a ready source. I will give it another stir in a week or two and see how decomposition is progressing.

Despite the slow composting process and the dryness, I had extracted about a litre and a half of liquid feed from the reservoir at the bottom of the bin prior to starting to add additional liquid in the form or urine. This extract has been used to feed peppers and tomatoes… applied to the soil not the foliage… and is the only feed that I have provided them with so far this year, with good results.

Although I had hoped that decomposition would be quicker than it has been so far, I am hopeful that this will turn out to be a valuable way to add fertility to the soil and will be a real case of turning something initially perceived to be a pollutant into a valuable resource. In the past urine and dog faeces were used in the tanning industry, but since this is not an option for me, I think I’ll stick with increasing soil fertility!

… and that other source of fertilizer…

The end product - composted human waste

The end product – composted human waste

Having written about urine as a source of nitrogen recently, I feel compelled to also mention that other sort of human waste that can be composted and used to enhance fertility. This seems to be increasingly referred to as ‘humanure’, but we’re really talking poo.

An aquatron composting toilet can be installed in a two-storey house

An Aquatron composting toilet can be installed in a two-storey house

When you live in an ordinary house on an ordinary street it’s fairly difficult to make use of this resource, although the Aquatron composting toilet can be fitted in an upstairs bathroom and there are other technical options such as the Separett range which require a fan to be run constantly, thus using electricity.  And so here, chez snail, this is one source of fertility that we don’t exploit. However, if you live in a different setting (as a number of my friends do) then you can collect and process humanure and use it to improve the fertility of your land. Many and varied are the compost loos that I have visited, but strangely I have very few pictures! The one thing they all seem to have in common is how civilised and un-smelly they are – often beautifully decorated.

Composting humanure at Karuna: it's initially collected in the dusbins before being transferred into the big bays behind

Composting humanure at Karuna: it’s initially collected in the dusbins before being transferred into the big bays behind

In some cases all waste is collected in a deep pit below the toilet structure and simply covered with a sprinkling of wood-shavings after each ‘deposit’, before it is eventually closed off, and allowed to compost for up to a couple of years. In others the waste is collected in a receptacle of some sort before being removed and composted away from the toilet itself. The latter is how the compost toilets work at Karuna, but in addition they ask users to separate urine (which is composted with straw) from solid waste (which goes into their large composting bins, tucked away behind the polytunnel). Interestingly, the process at Karuna seems to generate no smell and the end product is an appealing-looking compost that they have used extensively on site to enhance tree growth. So, whilst this is not an option open to everyone, it’s interesting to know that our waste need not go to waste.

Inspecting the end product at Karuna

Inspecting the end product at Karuna

Peeing in a bucket

I promise this is my last post about saving water for a while, but there are a couple of things I want to mention that have cropped up as a result of recent posts.

First, this week I decided that I would investigate a little more how much water we were using in the shower. It turns out that Mr Snail-of-happiness only spends about 3 minutes in the shower, whilst I spend about 5.5 minutes in there. Both times are much shorter than the average in the UK, which is 7.5 minutes. I also measured the water I used, so that I could find out the rate of flow of our shower. Our electric shower, it transpires, delivers about 4 l of water per minute; this is the target suggested by the Energy Saving Trust, so clearly we are not being excessive and I can stop considering changing the shower in order to reduce consumption.

Second, my friend Perkin from High Bank (a fabulous place to go for a holiday if you are looking for a cosy self-catering cottage close to wonderful places for foodies) tried to post a comment on my ‘more water-saving‘ post, but despite repeated attempts was unable to do so. What he tried to write was:

What about urine as a garden fertiliser, either neat on the compost heap or diluted on plants. It has the double benefit of massively saving toilet/flushing usage and of providing a free plant feed. Not the most socially acceptable of ideas, the fact that our compost heap faces a pub beer garden has caused surprise gasps 🙂

Well, we have a relatively private garden, but even so it’s fairly difficult for us girls to introduce urine directly onto the compost heap!

Urine is full of nitrogen and, because nitrogen is water-soluble, it’s one nutrient that gets washed out of the soil very easily. Many farmers (and gardeners) spend lots of money buying nitrogen fertilisers to apply to their land. Inorganic nitrogen fertilisers are produced by energy-demanding chemical reactions whilst all the time we flush away a natural source of nitrogen, treating this fantastic resource as a waste product.

A camping toilet, for discreet and civilised nitrogen collection.

A camping toilet, for discreet and civilised nitrogen collection.

So, Perkin is right – if we want free plant food and to save water, we should be using our pee in the garden. And the solution to collection? As the title of this post states – peeing in a bucket! OK, you may not like the idea, but it’s perfectly practical. Lots of camping and caravaning suppliers sell ‘camping toilets’, which are, essentially, a bucket with a toilet seat and a lid that seals well. Generally, the expectation is that these will be used with chemicals, but there is no need – a nice thick layer of wood shavings in the bottom will soak up the liquid and you can sprinkle more on as required. In fact, this is a great solution because the wood is carbon-rich and the urine is nitrogen rich, so you get a good balance of these two important elements to go on your compost heap. And, all that nitrogen acts as a great compost activator, so composting should happen nice and quickly.

So, don’t be squeamish – turn your waste into vegetables and save water, money and energy.

More water-saving

Following on from yesterday’s post referring to the report from the Energy Saving Trust, I want to examine what it is possible to do to reduce water consumption. But before I do, you might be wondering why the Energy Saving Trust wrote a report on saving water… well, according to their website, they ‘offer impartial advice to communities and households on how to reduce carbon emissions, use water more sustainably and save money on energy bills’. Energy and water are linked because lots of the water that we use in our homes is hot (showers, baths, cups of tea…) and so reducing water consumption can also reduce energy consumption. In addition, producing the water that comes out of our taps requires energy because it is treated to get rid of pathogens etc and when we send it on its way down the drain, it also has to be treated to make it clean enough to release into the environment. The EST says:

Heated water (for activities such as baths, showers, washing up and water-using electrical appliances) contributes a lot to energy bills. But this link, and its implications, often goes unnoticed by householders

Unfortunately, I was not greatly inspired by the report and the measures suggested in it. The EST doesn’t really seem to know who their target audience is, so the recommendations they come up with are a mix of things we can do as individuals and things that governments should do. This is their final list:

  • Aim to replace all remaining old or high-flow showerheads with water efficient showerheads (with flow rates of eight litres per minute or fewer).
  • Increase efforts on water efficiency education, specifically to promote the benefits of shorter showers.
  • Aim to either retrofit and/or replace all high-volume flush toilets.
  • Ensure that the most energy and water efficient machines available are promoted and incentivised.
  • When purchasing or replacing waterusing appliances, choose the most energy and water efficient model.
  • Increase the penetration of water meters in GB housing stock. Reported uptake of water efficient devices and behaviours was found to be greater in metered properties. The rollout of water metering can also provide a key opportunity for householder engagement and education on household-specific water saving opportunities.
  • Seek to combine water and energy saving education and delivery schemes for the benefit of the consumer.
  • Support and promote the Water Label by linking with built environment, procurement and water efficiency initiatives.

Not much for us ordinary folk to work with there, but there was a list in a table on page 28 comparing what people do in metered vs unmetered homes, that might be a little more helpful:

  • Wash dishes with a bowl, not under a running tap
  • Have a cistern displacement device
  • Have an eco-showerhead
  • Use a dishwasher eco-setting
  • Boil only what they need in the kettle
  • Use a water butt in their garden
  • Have a dual flush toilet
  • Do not run the tap whilst brushing teeth
  • Fill the dishwasher before use
  • Fill the washing machine before use
  • Use a hose trigger when watering garden
  • Do not have a dripping tap

But, frankly, I was looking for suggestions that were a bit more creative, and statements like “Flushing the toilet is an unavoidable fact of life” is, frankly, simply not true. First of all, you don’t always have to flush – for example lots of people don’t at night because of the noise; second, there are toilets that use no water, and I’m not talking about huts at the end of the garden, these days there are all sorts of high tech solutions (see, for example, The Little House Company); and third, I know lots of folks who use urine as a resource – on the compost heap or as a liquid plant feed. Perhaps the Energy Saving Trust think we’re all too squeamish to take responsibility for the waste we produce.

That aside – and I know there are people who live in situations where there is little choice about dealing with human waste – there are all sorts of ways we can use our water more creatively and more efficiently. Metan, one of my favourite bloggers, wrote a post a while back in which she described her use of grey water from the washing machine. A simple solution with a pipe allowed her to water her lawn with water that would otherwise have just gone down the drain. Living in Australia, water is a precious commodity, so she found a way to use it twice. And in a comment after yesterday’s post, my friend Linda described multiple uses of one lot of water when she’s camping.

No hose pipes here: this courgette plant is certainly doing well on washing-up water

No hose pipes here: this courgette plant is certainly doing well on washing-up water

When the garden needs water, we always use the stuff we’ve washed-up with (in a bowl not with a dishwasher). Similarly, if I hand wash clothes, then that water goes on the garden too… or in the toilet cistern if it’s wet outside. In fact, hand washing is criticised in the EST report because it uses so much more water than a full washing machine. Well, fair enough if you have sufficient delicate washing to fill your washing machine, but often you don’t. And I actually use very little water for hand washing because I use Euclan, a washing liquid designed for wool that requires no rinsing.

Whilst reducing the time you spend in the shower or the number of baths you have can cut down on your water use (as suggested in the report), using your water creatively and more than once (not suggested in the report) can have a huge impact, as you can see from the figures I quoted yesterday. So, if your shower is over the bath, next time you have a shower, leave the plug in and use the soapy water in the toilet cistern for the next few flushes… you’ll be amazed the difference it makes to your water consumption.

And now I want to know – has any one else got good tips they’d like to share about saving water? I’m wondering if we can cut down a bit more!

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