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Water Conservation in the home

We can no longer
take water for granted!
So here's some tips for saving water -
and using it more wisely.

Seven tenths of our bodies are water, but this does not reflect our attitude to this precious natural element. Water is being constantly recycled by the natural processes of the planet. Millions of gallons are evaporated and desalinated by the sun from the land and oceans every day and then returned to the earth's rivers, lakes and groundwater through rain and snow.

This cycle has maintained conditions for life on earth for millions of years. But the majority of us post-industrial humans have, to a large extent, lost contact with natural cycles.

Water appears miraculously at the tap and conveniently disappears about 30 centimetres later down the plughole, to be dealt with; cleaned, treated with chemicals and often zapped with ultraviolet light, finally reappearing at the tap. This is a cycle imposed upon water in urban areas; unnatural, polluting and wasteful.

A recipe for disaster

  1. Mix one part excreta with 100 parts clean water.
  2. Send through miles of pipes to a central collecting point.
  3. Allow to stand.
  4. Add chemicals to clean the effluent and kill any harmful bugs, or irradiate with ultraviolet light.
  5. Stir vigorously, adding plenty of oxygen, then allow to stand.
  6. Dump the clean water, (still rich in nutrients from the excreta) into the nearest body of water.
In this way the nutrients contained within our wastes are not utilised, while a typical user contaminates 13,000 gallons of clean water to flush away only 165 gallons of bodily waste a year. This is one example of our wasteful use of clean water.

Why conserve water?

Ultimately, the fresh water available to you as a user depends upon the amounts of rainfall, local hydrology and the geology in your area.

If we take out more water than the natural system will allow then this leads to a lowering of the water table and possible dramatic effects upon water quality, future water supplies and agriculture. This also has harmful consequences for the wildlife/amenity value of the landscape, reducing flowing rivers to muddy puddles.

Faced with the problems of over abstraction from natural water bodies the knee-jerk reaction is to construct more reservoirs. This solution again impacts heavily upon the wildlife/amenity value of natural landscapes and also alters the hydrology of the area. The sane alternative to this tinkering response is to use the water you have in a sustainable way by conserving and recycling it.
Value your water supply.

A man full of water

How much do we need?

To sustain a reasonable quality of living requires about 80 litres of water per person per day. But the average consumption ranges from 5.4 litres (barely enough to live on) in parts of low rainfall countries during the dry season, such as the Sahel, to 500 litres per person per day in the USA. Much of this extra use is carelessly wasteful.

In the U.K we withdraw about 507 cubic metres of water per person every year from both renewable and non-renewable resources. 20% of this is used for domestic purposes which adds up to about 278 litres per person per day, and this figure is rising!

The Environment Agency estimates that the growth in water demand in the U.K until 2011 will be attributable to: 20% from population growth, 40% from increased consumption and 40% from leakages. Losses from a tap dripping at 30 drops per minute add up to about 250 litres per month!

How to conserve the water in your home

  1. Check for leaks , especially faulty washers, and repair them!

  2. Fit water conserving devices .Many commonly used appliances can be modified to conserve water or bought specifically for their water conserving qualities:

    • Spray taps and faucet aerators are an alternative to steady flow taps enabling a smaller volume of water to achieve the same results.
    • Low flow shower heads can be fitted to maximise water coverage and minimise water volume.
    • In the toilet: By adding a plastic bottle filled with water, and sealed, inside your toilet cistern or by adjusting your ballcock, the amount of water used per flush can be reduced to a minimum. Alternatively a dual flush toilet system can be fitted which discharges a small volume of water for liquid waste and a larger volume for solid waste, efficient flushing depends upon the velocity of the water rather than the volume which tends to be grossly out of proportion with the waste that the water flushes.
    • Install a compost toilet, if appropriate: you can do away with using water to flush away your wastes. The added benefit to this simple technology is the rich compost you get at the end of the process, returning nutrients back to the soil that would otherwise end up in rivers. In China and Japan night soil (as it is called) has been scrupulously collected for centuries to fertilise the fields. Compost toilets need no water and depend upon bacterial action to break down harmful bugs in the waste.

  3. Think twice : much water conservation in the home is common sense:

    • Washing clothes: Use full loads in your washing machine, or if purchasing look for economy features such as half load capability or reduced water consumption.
    • Refrigerate any drinking water in order to prevent running the tap for long periods waiting for cold water.
    • Conversely, insulate hot water pipes to prevent running the tap for long periods waiting for hot water!
    • Wash dishes by hand, using one bowl for washing and one for rinsing. Bowls are filled with less water than it takes to fill the sink.
    • Use showers instead of baths. Have baths as a treat, a sensual experience to be relished once in a while. Have showers instead, and if you are very keen on water conservation you can share your shower with a friend.
    • Collect rainwater. In most parts of the U.K. the water collected from rain falling on the roof of an average house could supply the water needs of at least one person provided that the water is stored. This collected water can be used for most applications but care should be taken if you suspect any leaching of particles from your roof surface. If this is the case then the water can still be used for washing your car, or bicycle, and watering ornamental, (non edible) plants.
    • Car washing: It is possible to wash a car with only one bucket of water. But does it really need washing?
    • Garden watering: To save water and to give your plants the maximum benefit it is best to water out of direct sunlight, i.e., in the evening. This will cut down on water loss due to evaporation. Avoid sprinklers, which use water indiscriminately, and try to target the water precisely where it is most needed. Grow plants in beds, not containers.
    • Save your cooking water and use as a stock or a base for soups; it can be kept for several days in a cooler or frozen.

  4. Write to your local water company and find out how much water it loses in its pipes through leakage and what measures it is taking to alleviate the situation. In some areas this figure is over one third. Demand to know why consumers should suffer shortages, rising costs and metering if the company will not plough more of its profits into conservation itself.

  5. Recycle more : All the water used in the home, apart from flush water, can be re-used to some degree. Water can be collected from seven main sources in the home:
    • Shower
    • Bath tub
    • Bathroom sink
    (These three together use 75% of non-flush water consumed in the home and contain less than 10% of particulates)
    • Washing machine
    • Utility sink
    • Dishwasher
    • Kitchen sink

How to collect the water

Making use of Waste Water

A temporary solution is to manually bucket the water, usually termed greywater, from the source to its eventual destination. A more sophisticated method is to re-route the drain pipes of the fixtures and appliances from which you intend to re-use water into a common discharge buffer tank. A small electric or hand pump may be needed if gravity feed is not possible, dishwashers and washing machines have their own discharge pumps which are capable of delivering water to an elevated storage tank.

Greywater qualities & uses

The quality of the grey water you collect ultimately depends upon what you put in it when it is clean, so to get good quality grey water you will need to filter out any particles by using a simple mesh filter on the plughole. Soap and detergent residues can be harmful so it is best to use bio-degradable cleaning products, sparingly.

If the greywater is passed through several filtering systems i.e a settling tank, then grease trap, then sand filter, the resulting water can be used with little worry over the potential accumulation of harmful chemicals. It can be applied to all types of vegetation.

If you do not possess the space or resources for this kind of filtration the grey water that you have so scrupulously saved can still be used to top up your toilet system, (if you have one), or used selectively in the garden.

Care should be taken to water only ornamental plants or mature well established vegetable plots, it is also advisable to avoid contact between the grey water and the vegetation itself, i.e water the soil around the plants only.

Sodium, contained in detergents, can build up after lengthy periods of application necessitating adding gypsum to the soil to lower the alkalinity which sodium causes. This build up can easily be detected by making a test for pH. Any possible harmful effects can be minimised by diluting the grey water with collected/fresh or filtered water.

Source - The Centre for Alternative Technology.
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Contact: Hari Srinivas -