My Water Use

Water is a very valuable resource... in it's own right, and because it takes a lot of energy and resources to get it to us, and to clean up the stuff we flush and forget or let gurgle down the plug hole without a thought.

To move water around takes a lot of energy... pick up a bucket of water and see how heavy it is.  Moving and treating water in the UK uses about 3% of our national electricity, as much as one large power station produces.

As part of my low carbon lifestyle, I'm very careful to reduce my water use, not just because we have a water meter and pay for what we use and what we need to have cleaned up after us, but because it lowers the carbon emissions that I'm responsible for. 

This household uses about 80 cubic metres of water a year, so my personal use is a about quarter of that, at 20m3... (about 55 litres per day) This is a half to a third of the average UK useage.

The biggest user of potable water in most households is the toilet, or 'water closet'.  There are two simple ways which will enable you to reduce your water use in the loo.  The first is to reduce the volume of your cistern by putting something solid in, so that when the flush empties the cistern, less water empties out.  There are various proprietory gadgets to do this... a 'hippo' is one of the best known, but essentially all they do is to reduce the amount of water lost at each flush. My cisterns have got a plasic bottle in which is filled with water.  The other simple way can be used in conjunction with this... it is summarised with the rhyme
If it's yellow, let it mellow; If it's brown, flush it down.
Yes folks, basically, if there's just urine in the toilet, there is no need to flush it away.  But if you've done a number two in the loo, you don't want someone else to have to experience that.  But we don't leave urine in the bowl overnight as it gives off too much of an ammonia smell.

Many modern toilets have a dual flush system... if you push the handle down quickly and release, you get less water coming out than if you hold the handle down.  Some toilets have a split button flush, so the smaller part of the button allows a smaller flush than pressing the whole button.  For old toilet cisterns, you can retro-fit a dual flush system. (Waterwise has a comprehensive list of retro-fit flush systems as well as many modern low flush toilets available.)

However, whenever I use a flush toilet, I feel that I'm wasting a valuable resource and  adding to unnecessary carbon emissions, so I have made myself a very simple compost toilet, inspired by one of my favourite books, Joe Jenkins' 'The Humanure Handbook'.  So my preference when I need to go, is to go to the outhouse in the garden, and use a commode and some sawdust.  I then collect this up together and compost it in a dedicated 'dalek' compost bin in the garden.  It takes 18 months or so to fill this compost bin with the sawdust/humaure mix, and then I leave it for about 4 years to completely compost down, after which I use the compost on permanent plantings like raspberries, currants and fruit trees.

When you flush the toilet and all the contents flow to the sewage works, the solids are relatively easy to deal with, as they settle out and are removed for incineration or, in more modern plants, used in anaerobic digestors to create methane or natural gas, which is either burnt and used to boil water to make steam to spin a generator for electricity, or may be added to the gas mains for domestic use.  However, the water and urine is difficult to 'denitrify'.. it has to have lots of oxygen added, either by pumping air through it or trickling it over beds of stones with a high surface area for the colonies of bacteria to use the nitrogen-rich nutrients and convert to atmospheric nitrogen.   So, my preference when it comes to disposing of my urine, is to pee in the garden.  I pee on woody compost heaps, into the hedge, or on shrubby borders.  The urea in the liquid is a great fertiliser and the plants use it to help them grow.  This is another way in which I reduce my carbon footprint, by not adding too much urine to the sewage works.

The other members of the family have normal toilet habits and do not use my compost loo or pee in the garden.  So when dividing the annual water meter readings by four to get my own share, I'm probably being generous, as I don't use the flush toilet as much as they do.

This is another big user of water in the home, and for us, probably an area which we could improve on.  Our washing machine is very old, (ie between 17 and 20 years old!) and I'm looking forward to replacing it with one which uses less electricity and less water.  But will our next machine last as long?

I'm not a fan of showering, and I rarely have a shower.  I have a stand-up wash with a flannel every day, and I love a long hot deep bath about once a week.  I don't know if my weekly bath and daily 'pirate wash' use more or less water than a daily shower, but I do know that my bath uses less fossil fuel, as I heat the water on my woodstove, but that's a different subject.

I do a lot of work in the garden and my composting activities and hand-weeding mean that my hands often need a good scrub.  I wash my hands in a particular way which reduces water use and means I can re-use the water.  I don't wash my hands under a running tap, I put the plug in and run a shallow sink of water, and use a scrubbing brush to get the worst off.  I then scoop this compost-laden water up with a pair of plastic cups and use it to water house plants.  I then fill the basin again and use soap for the second and final wash.

When I brush my teeth I wet the toothbrush before use and then turn the tap off.  I use a mug of water to rinse my mouth,  then use the tap to rinse the basin out.  This seems to be fairly economical with water use.

I am mainly responsible for the several-times a day duty of washing up, and this is one of our biggest water uses.  I don't do anything particularly special here... the bowl of plates, pans and cutlery have hot water put over them, the sponge given a squirt of biodegradable washing up liquid, and then when washed, each item gets rinsed under the cold tap to wash off the suds, and the items are put on the rack for drying.  I choose not to use a tea towel as my Environmental Health training taught me how tea towels are a great way to wipe dirt back onto crockery.
What I do do, though, is I sometimes use the water left in the washing up bowl to pour over the containers in the conservatory in the summer... so our tomatoes and cucumbers are often watered by washing up water. But this is only in the summer, when the plants are growing fast and are thirsty.

I wash vegetables and if there's soil on them, such as 'mucky carrots' or potatoes from the garden, I keep the soil-laden water to water the plants, as I don't like wasting water or the nutrients and minerals that this contains.

We have several water butts connected to downspouts from the roof, so there is always copious rainwater available in our garden for watering plants.  I sometimes use 'greywater' from the washing up to water plants too, or the hedges.  I have just purchased a diverter valve for the bath outlet, but I haven't fitted this yet but I hope to soon.  This will enable me to decide to put some bathwater into the sewer (if it contains kids bubble bath or shampoo) or if the water is less chemical-laden, I'll be able to divert it to the garden.  I haven't yet decided where this will go, but the aim will be to reduce the pressure on the sewage works and irrigate the garden.

Soon after we moved here I decided to install a greywater recycling system in the shared driveway between our house and the neighbour's house.  I dug a hole and installed a plastic dustbin, which had roof, sink and bath water flowing into the top and a pipe leading to the sewer at the bottom.  I was able to lower a brewing bucket into the dustbin and collect grey water, or to put a 'straw trap' in there to intercept the solids from our greywater stream, and I'd periodically replace the straw and compost it.  However, my neighbour found that the base of the dustbin was leaking (where the outlet pipe was affixed) and the soil was saturated, which isn't good for house foundations, so he made me fill it in.  The water now flows straight from the roof and sinks etc into the sewer.  I learned several things from this experiment, the most important is that grey water cannot be stored, as the nutrients in it allow a thick bacterial slime to grow, which blocks pumps and pipes.  If you collect greywater, use it immediately.

Much of what we buy has an 'embodied water footprint' and because we aren't big consumers of gadgets, electronics, processed food, etc, we are keeping that relatively low. 

However, we do get a daily newspaper, and I subscribe to a weekly NewScientist and quite a few other magazines, all of which use water in the paper use, and their eventual recycling.

The fruit, vegetables and other food we buy also have a hidden water footprint, as most crops are irrigated, and some may be washed before going to the wholesalers.  I wear cotton jeans and teeshirts and cotton is also an irrigatedcrop... and as it's grown in hotter climates, I'm responsible for using their scarcer water resources.  However, we often buy second hand clothes, so I'm not always responsible for the original product and it's embodied footprint.


Mrshappyanna said...

Good article John!

Edna and Mary said...

Eh up deary, we love your water saving tips! We've got some of our own here if you fancy taking a gander at 'em.
Edna and Mary x

Karin said...

We have a similar dilemma with regards to our fridge as you have with your washing machine. It's over 15 years old, so not the most efficient, but I think it might be a better use of the Earth's resources if we keep it until it finally gives up. I just hope it won't be too full when that happens.

Bom said...

As well as buying second hand clothing it is also good to wear clothes till they wear out. People seem to have forgotten how easy it is to patch or repair clothes as they are now relatively cheap.