The Permacultivator - Journal of Cool Climate Permaculture
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Water Usage and Storage 

by Richard Wirsu

Wingecarribee Council, on its phone holding message, states that the average home uses 900 litres of water per day! Rosemary Morrow quotes the Sydney Water Board figure of 475 litres per person per day in 1991! These are figures that indicate the scope for each of us to do our small part towards conserving water and using it wisely.

The CSIRO, in a booklet published in 1988, proposed a number of alternative water sources (other than directly tapping surface or ground water): re-use of waste water, treatment of sewage, cloud seeding, icebergs towed from Antarctica, desalination of brackish water (desalination of seawater requires large amounts of energy) and rainwater tanks.

Some of these suggestions are beyond the scope of most who are interested in conserving water - towing icebergs probably won't help those of us in the Southern Highlands much! - but others could be of value. Rainwater tanks are becoming a more attractive proposition with the charges now being levied for mains water use. For people who are far enough out of town to be independent of the mains system - good luck! But what of those living in town?

The Council view:

Wingecarribee Council is currently in the process of producing a document which outlines the Council approach to alternative water supplies in the area. Council supports the installation of roof water catchment tanks with two main provisos - firstly, the tank water supply must under no circumstances be interconnected with the mains water supply, to avoid contamination, and secondly, it should be safe and aesthetically acceptable. In light of this second condition, Council suggests that a nominal Building Application be submitted, for which a fee is charged, including for notification of neighbours, which must now be done by Council. It is thus quite acceptable to run a separate pipe and extra tap into the kitchen from a tank or use it for gardens, etc..

Bores or springs can be tapped for domestic use but again cannot be interconnected with mains supply and it is suggested that chemical and bacteriological tests be made on the water. These can be arranged by Council for a fee.

Council policy does not permit the construction or use of dams on residential property, for safety reasons. Outside the residential area, contact the Dept. of Water Resources and the Soil Conservation Service for advice and requirements.

Rainwater tanks:

A water audit gives information on consumption rates and can take into account recycling strategies already in place, such as running grey water into the garden, etc. A water audit can be organised by measuring consumption rates for typical processes in the system, such as dishwashing, clothes washing, use of toilet, cooking, baths/showers, etc and then drawing up a table to record frequency of use of each item each day for a week. Totals can be checked against mains water meter readings.

For those already on mains water the cost of rainwater tanks needs to be balanced against savings that ensue for the environment and hip pocket savings in mains water charges. A tank to supplement mains supply is certainly viable. Galvanised steel tanks can be purchased, excluding plumbing and installation, for anything from about $200 (100 gal. - 440 litres) to $1600 (5000 gal. - 22400 litres). Tanks are now available constructed from Aquaplate steel, in which a food grade polymer skin is bonded to corrosion resistant steel. Concrete tanks are more expensive and are probably more appropriate for larger properties. Glass fibre tanks are also more expensive.

Installation of tanks:

Installation of galvanised tanks is reasonably straightforward and may be done by a qualified plumber or handy-person. Correct installation is necessary to protect warranty.

Caring for your tank:

Keeping water in tanks fresh can be assisted in a number of ways:

  1. Obtain as large a tank as you can - the larger the body of water, the healthier it will remain.
  2. Completely cover the tank and cover the inlet with a screen to keep out mosquitos, insects, birds, leaves, etc.
  3. Instal a first flush filter, which will send the first rain collected, with its dust and pollutants, past the tank and only admit water after a certain time has elapsed. These may be constructed from one of the designs available in various texts, or a commercial version is available which diverts the first 50 litres and utilises a ball shut-off to divert water.
  4. Bill Mollison also suggests the inclusion of a bag of limestone, shell or marble chips to make the water hard (alkaline) and thus prevent heavy metal uptake from the water.


Many authors recommend the recycling of greywater - from laundry and kitchen - by running it out onto gardens. This practice does not seem to harm growth provided greywater is not always deposited in the same spot and some monitoring of what is in the water takes place. A few simple tests reveal that bathwater, dishwashing water and rinse cycle water from the washing machine are all about pH 7, whilst the suds cycle water from a washing machine is pH 9/10 - probably a little high. "Biodegradable" products which may be contained in greywater will supposedly break down but in large quantities they may still accumulate in soil and become pollutants. Care is needed.

Council view on Greywater:

Bucketing of greywater onto gardens during drought conditions seems to be acceptable but no permanent connections to run greywater outside are permissible unless they comply with the Australian standards set by the Dept. of Health for sullage disposal. Essentially this means the use of a septic tank (min. size 1500 litres) and absorption trenches, or one of the processing products such as Envirocycle or Biocycle.


State Government Update May 2002

Jill Cockram, our State government correspondent, reports from Macquarie Street.

A news release dated 15th May, from the NSW Premiers office tells us that the NSW Government plans to amend Special Environment Planning Policy No.4 in order to encourage people to install larger rainwater tanks. Up till now you could only install a tank up to 5,000litres capacity without development consent but the amendment will allow up to 10,000 litre tanks in the Sydney, Illawarra and Blue Mountains areas in an effort to overcome the increasing pressure on the current water catchment system.

If every family installed a large water tank for flushing the toilet and watering the garden there would be a daily water saving equivalent to half of the water in Sydney Harbour or 555 Olympic swimming pools. The other advantage is that there would be less storm water run-off carrying rubbish into our waterways.

Previously, a household could only install a rainwater tank with a backflow device (to prevent tank water entering the reticulated water supply) if it was to be connected to the reticulated system. Sydney Water has begun free installation of new water metres with a backflow device (in the above areas only) for people wanting to install larger tanks. The Government is also considering a rebate system or discount in price as an extra incentive to encourage installation of large water saving tanks for Sydney, Illawarra and Blue Mtns residents..

Strathfield Council was the first council to make rainwater tanks compulsory in all major developments. The drought we are currently suffering may encourage all other councils to amend their development planning by-laws to do the same and possibly create more stringent guidelines for sustainable house designs also.

Australia is described as a dry continent but if we harvested the rainfall wisely, in every backyard as well as on farms, we could drought proof the country to the point where dry spells wouldn't devastate the economy and the ecology so profoundly. Conservative use of water - both tank and reticulated town water - is more in tune with the unpredictable weather patterns of this old continent.

It is predicted that future wars around the globe will be fought over access to water. Perhaps it is timely to start treating the stuff as is it were liquid gold! So, even though we fall outside the designated area for the government initiative on large household water tanks, investment in a tank for your backyard will be returned in a few short years. Not just financially but in health benefits - no fluoride or chlorine.

The Water Efficient Garden

Debbie Hebbard provides some timely summer ideas


Water is the most precious and essential of resources on earth. Since the dawn of time ancient cultures recognised the importance of water. The Aboriginal people have many water spirits, with lakes, rivers and water holes being created in the Dreamtime.

With the coming of technology, the dependence on natural water sources and rainfall was reduced. This has tended to result in a ‘cheapening’ and heavy / excessive use of this essential resource. Some people still think ‘so what, it’s only water’.

Water consumption has tended to double with each generation eg When water was hand pumped or carried from the stream the average consumption per person was less than 20 litres a day, in the 1950’s it was around 200 litres and the early 1990’s 300 litres. This increase reflects our use of water-intensive machinery like dish washers and washing machines, as well as the phenomenal amount of water used in producing every day products.

While we can consciously change our home water consumption rates, this hidden water usage is often over looked. A significant change in either production methods or our personal consumer habits and demands is needed to reduce this area of consumption. See Table 1 below

Water Used in Production
1 kilogram bread 2 600 litres
1 kilogram meat 41 500 litres
1.5 kilograms chicken 10 900 litres
1 orange 500 litres
1 bottle beer 4 litres
1 mans woollen suit 1 020 000 litres
1 tonne aluminium 1 340 000 litres
1 copy Saturday’s paper 50 litres

In the Wingecarribee Shire water consumption has remained fairly static, despite population increases, since 1993 when the new ‘user pays’ costing system was introduced. This would indicate a reduction in the average water consumption per household.

See Table 2 Reference WSC Water & Sewerage Dept.


TOTAL (Ml/pa)
3409 (to date)
12 (to date)

Obviously we are making changes, if only to minimise the water bill. From a purely cost saving perspective, developing a water efficient garden may reduce our consumption by 50% or more . This reduction makes better use of our existing water supplies, with environmental, social and financial benefits to the community at large .

Grey Water

Grey water is the water waste from the kitchen, laundry and shower, this can amount to 60% of the internal water used in an average home. Reusing and recycling this water can reduce your total water consumption greatly. With the forecasted dry summer ahead grey water may be the life saver you need.

The more aware you are of what goes down your drain, the better. Using pure soap for washing and bathing ,and cleaning with 'gentle' totally bio-degradable substances, allows you greater scope for using your grey water. We should all be trying to 'clean up' our waste water by taking care with what is poured down the drain. It is especially important if you are going to use that water on the productive garden.

Grey Water & The Garden

Careful consideration should be given before using grey water.

Being conscious of what substances you use in the home for cleaning and washing is important. Many typical household cleaners may not be fully bio-degradable, may contain harsh chemicals, produce unpleasant by-products on breaking down or react with other chemicals in the waste system.

Grey water can be saline, many laundry powders are bulked out with sodium salts, this should not be a problem after dilution, unless your water source is naturally saline. If this is the case avoid watering salt sensitive plants like citrus, stone fruit, beans, radish, bulbs and flowers. Figs, olives, asparagus, silverbeet & spinach are all tolerant of saline water to 2000 mg/l. Some detergents now use potassium salts, so look around when next shopping.

Boron is present in some detergents and cleaners. It stunts plant growth and scorches the leaves, in a hot dry summer these symptoms may be mistaken for drought effects, not boron toxicity, be careful as boron is toxic to humans. Choosing products without boron is possible.

Kitchen waste may be greasy, a double grease trap will remove grease residues most effectively.

Ideally a permanent water purifying and filtering system could be installed (different councils have different regulations). A biological filter like a reed bed can remove most nutrients, disease organisms and pollutants so the remaining water is clean for garden use. This filtered water can be used freely on the garden.

Basic principles for using grey water :


J20 Summer 97-8

Self Watering System for Tree Seedlings

Jan Butler sent this handy suggestion.

Here is a simple design for a watering system for precious seedlings when you just can't be there. This system works best with hot days and cool nights.
You need a small lidless drum painted black or dark coloured, with a cover of black plastic held with say a ring of rubber from a tyre tube and weighed down in the centre with a stone. A small funnel and tube is placed in the drum as shown in the diagram and about 50cm deep water is placed in the drum. Water evaporates during the day and condenses on the plastic cover at night and drips into the funnel and tube to be delivered to the plant below ground level.

Water: Garden Glutton or Garden Guru

by Jill Cockram

With water being a precious commodity I thought it might be useful to research garden water usage for greater sustainable water use. Sometimes water restrictions have the opposite outcome than desired as gardeners on water restrictions tend to water compulsively more often and sometimes unnecessarily, simply because they have limited hours within which to keep their gardens alive. With the knowledge that around 40% of my household water usage goes to maintaining the garden I thought that getting down to the water needs of individual food crop varieties may be another way to reduce garden water wastage.

We have been confronted with “waterwise” tips for some time now – installing water tanks, re-using grey water, watering outside the hot daylight hours, and using a thick mulch to conserve soil water levels. Drip irrigation is probably THE most effective way of water conservation within your vegie beds. However, for someone like me who has yet to become that organised, the next best way is to know how much and when our plants need watering over the hot, dry seasons we have been experiencing of late.

Firstly, fruit trees and citrus need the most water in the establishment phase, when they are establishing root systems. Good deep watering once a fortnight on our clay soils accompanied by thick mulch should be sufficient. If you want to be even more water wise, you could sink some 500 mm lengths of 100 mm polypipe (with holes drilled at the bottom end) vertically in the planting hole with the tree roots keeping the top end at ground level. Pour water into these pipes to diffuse around the root zone without any surface evaporation. Once established fruit trees can withstand long dry periods, but they will benefit and provide a better crop from the occasional deep watering as the fruit is swelling. If you are on tank water alone, the fruit trees might have to miss out, unless you can bucket grey water to them – the result would be less volume but more tasty fruit at the end of the season.

Berry crops:
Most berries are best manured, mulched and watered in late winter, then left until spring when deep watering occasionally will encourage heavy flowering and fruiting. Once the fruit is developing, regular watering will help create a bumper crop in virus-free plants.

Vegetable crops:
Root crops – as a general rule water when the soil is drying out. Although they can survive dry spells quite well, if you leave it too long between watering, the roots will split when water is finally applied.
Onions – Water when seedlings are getting established then ease off as overwatering late in the season will create lush tops, delay maturing and reduce keeping quality.
Peas and beans – Being large seeds, they should be deeply watered at planting time and then left until the young shoots appear. Occasional watering is sufficient until the flowering and pod swelling stage when a little extra water will increase the crop.
Tomatoes – Water regularly if growing from seed in the punnet stage. After planting out, only water regularly after flowers appear – the water stress can bring on earlier flowering after which watering will allow the fruit to swell. Overwatering could decrease the flavour in the fruit. Mulch is essential to provide cool soil and encourage continued blossoming and fruit set
Squash and Corn - Both these families like to have their roots in a swamp and will be much more productive in size and number of fruit for the provision of cool damp soil. Mulch is essential. Avoid overhead watering to reduce the effects of mildews on production. Perhaps a soaker hose under straw would be the best option here. These two plants are great companions in the same bed.
Brassica - well spaced and once established will be reasonably drought hardy – perhaps extra watering a couple of weeks before harvesting.
Leafy Greens - benefit from regular watering and liquid manuring otherwise they can bolt to seed early or be tough in texture.

Seedling trays of newly planted seeds must never be allowed to dry out completely – especially if in a greenhouse. If a tray is dried out, a misting spray of rainwater is needed.
Potted plants are also in danger of drying out and dying if left too long without water. I find that plants have a greater chance of survival in my garden.

As an easier maintenance plan, it is worth planting those vegies that have similar watering requirements in the same bed – high/regular in one bed and occasional watering in another.

Reference: Grass Roots No.65

J47 Spring 2005 -Summer 2006