FEATURE ARTICLE: HOUSEHOLD WATER CONSUMPTION AND CONSERVATION ACTIONS


INTRODUCTION

Water conservation makes demands on most South Australian people and sectors of the state's economy. This article focuses on the actions adopted by the state's household sector in adapting to these demands. Attention is given to the periods when water saving strategies were introduced by the South Australian Government, namely Permanent Water Conservation Measures (2003) and Level 3 Water Restrictions (2007).

Household consumption of mains water supplied by SA Water (the state's principal water provider and the metropolitan area's only water provider) is examined along with details of household water conservation actions, as provided by the ABS Household Survey - "Environmental Issues: Water Use and Conservation", March 2010 (cat. no. 4602.55.003).


WATER SOURCES

MAINS WATER

Recent ABS data show that (at March 2010) almost all (99.6%) of Adelaide's households and 69% of households in the rest of the state were connected to a mains/town water supply. The corresponding national levels were 98% for capital cities and 84% for the rest of state/territory.

Recent data from SA Water show that South Australian households reduced their average daily consumption of water from 756 litres (L) in 2000-01 to 501 L in 2009-10, a decrease of 34%. For the corresponding period, the state's daily water consumption per capita (or person) fell from 539 L to 385 L - a 29% decrease.

Permanent Water Conservation Measures, which aimed to reduce water consumption in the long-term and to promote water efficiency across the community, were put in place by the state government on 26 October 2003. This had a noticeable effect, with daily average household water consumption falling by 15%, from 762 L in 2002-03 to 644 L in 2003-04. Similarly the state's average daily consumption per capita fell by 13%, from 532 L to 460 L.

Between 2003-04 and 2005-06, the average daily consumption of water by households stayed around 640 L, followed by a slight increase to 660 L in 2006-7. However, in 2007-08, after the introduction of Level 3 Enhanced Water Restrictions (1 January 2007), water consumption fell markedly to 523 L and remained at this generally lower level in 2009-10.

The Level 3 Enhanced Water Restrictions ceased for most of the state on 1 December 2010, when Water Wise Measures came into effect. The Eyre Peninsula continues to be subject to Level 3 Enhanced Water Restrictions (post 1 December 2010).

The following graph shows recent patterns in daily average residential water consumption for South Australia, both for households and per capita.

City (Adelaide area) households generally had a higher average daily water consumption than those in the country. Derived data from SA Water show that (in 2009-10) Adelaide households used 521 L per day compared with 438 L for the rest of South Australia.


RAINWATER TANKS

ABS data show that rainwater tanks provided water for 49% of South Australian households in the twelve months to March 2010, compared with 26% nationally. Moreover, 83% of South Australian households outside of Adelaide (non capital city) used this resource, compared with 37% (non capital city) households nationally.

Over the recent decade, and of all the states and territories, South Australia had the highest proportion of households using rainwater. Also, South Australia consistently exceeded corresponding national levels for rainwater tank usage.

WATER CONSERVATION MEASURES BY HOUSEHOLDS

According to SA Water data, South Australian households consumed almost one third of their water in the bathroom - for self washing (20%) and flushing the toilet (11%). The washing of clothes was estimated to account for a further 16% of household water consumption, while cooking, cleaning, dish-washing and drinking (combined) accounted for 11% of total household water consumption.

When water restrictions commenced in South Australia, particularly the Level 3 Enhanced Water Restrictions (2007-08), the average daily use of mains water by households decreased by nearly one fifth from previous annual levels. Besides limiting the use of mains water on gardens, the restrictions also guided households to adopt other water saving behaviours.

To some degree, such actions may be reflected in results from the ABS Household Survey of "Environmental Issues: Water Use and Conservation", which recorded details for the twelve months to March 2010.


USE OF RAINWATER INSIDE THE HOUSE

The use of rainwater (from tanks) was a primary water saving method reported by South Australia's households in the twelve months to 2010. It provided the main source of water supply for bathing and showering in 12% of households (compared with 6% nationally) and for the washing of clothes, 12% compared with 7% nationally.

The use of rainwater for washing clothes was mainly confined to households outside of capital cities. For example, 41% of households outside of Adelaide used this method compared with just 2% in the city. Nationally the corresponding proportions were 15% (outside capital cities) and 7% (in capital cities).


OTHER WATER CONSERVATION MEASURES INSIDE THE HOUSE

For the 12 months to March 2010, 62% of South Australian households took steps to save water in the bathroom, compared with 59% nationally. Another 59% of South Australian households acted to save water in the laundry compared with 55% in Australia. A further 41% took steps to save water in the kitchen, slightly below the national result (44%).

To March 2010, the South Australian household use of water saving devices was as follows:

• water-efficient shower heads, 65% of households - up from 37% in 2001;
• dual flush toilet, 89% of households - up from 72% in 2001.

To March 2010, other water conservation actions taken by South Australian households included:

In the bathroom:

• taking shorter showers, 36% of South Australia's households - compared with 37% for Australia;
• turn off the tap while cleaning teeth/shaving, 23% of households - compared with 24% for Australia ;
• check and fix leaking/dripping taps, 13% of households - compared with 8% for Australia;
• installed water saving product, 13% of households - compared with 11% for Australia;
• collecting grey water, 12% of households - compared with 9% for Australia.

In the laundry:

• only using washing machine when fully laden, 25% of South Australia's households - compared with 27% for Australia;
• collecting grey water, 14% of households respectively - compared with 11% for Australia;
• buying a water efficient washing machine, 14% of households - compared with 11% for Australia;
• adjusting water level when washing, 13% of households - compared with 12% for Australia.

In the kitchen:

• use plug in sink/don't leave tap running, 15% of South Australia's households - compared with 14% nationally;
• wait until sink full before washing dishes, 15% of households - compared with 13% nationally;
• only use dishwasher when fully loaded, 11% of households - compared with 12% nationally;
• use less/reuse water in sink, 11% of households - compared with 7% nationally.

SOURCE OF WATER FOR OUTDOOR USE

Recent SA Water data suggest that around 40% of the average household's total water consumption is used for outside purposes, in particular for watering gardens and lawns. This section examines water usage and conservation by South Australian households that kept a garden.

ABS data show that the percentage of South Australian households having their own garden fell from 91% in 2001 to 87% in the 12 months to March 2010 Interestingly, the largest change occurred recently, between 2007 (when the proportion was 90% ) and 2010. This change may be attributable in part to emerging trends or preferences in building construction, towards dwellings without gardens.

The main source of water used in the garden by South Australians in 2010 was mains/town water; 58% of households used this source, down from 67% in 2007. Nationally the corresponding level was 45% in 2010.

Rainwater from tanks became more prominent for outdoor watering in South Australia, up from 8% in 2007 to 15% in 2010. 'Not watering' (or relying on rain) also became a common practice, up from 9% in 2007 to 12% in 2010.

A greater proportion of Adelaide households (66%) used mains water on their gardens in 2010, compared with 45% for capital-city based households in Australia. Conversely, a lower proportion of 'ex-metro' households, outside of Adelaide used mains water on their gardens, 35% compared with 45% for non capital city households/rest of Australia; moreover, these South Australians used proportionally more rainwater from tanks (25%) than non-capital city households/rest of Australia (14%).

WATER CONSERVATION ACTIONS OUTSIDE THE HOUSE - IN THE GARDEN

Of South Australian households with gardens, 70% reported water saving activities in the twelve months to March 2010 compared with 78% in the twelve months to March 2007. The Australian estimates for these two periods were 62% and 71% respectively.

The main water saving steps taken by South Australian households in their gardens over the 12 months to March 2010 and to March 2007 were:

• use of mulch, 31% of households at March 2010 and 19% at March 2007;
• only water if necessary, 26% of households at March 2010 and 25% at March 2007;
• water at cooler times of day, 20% of households at March 2010 and 17% at March 2007;
• use grey water, 19% of households at March 2010 and 21% at March 2007.

SUMMARY

While South Australia's households are mainly reliant on mains/town water supplies, they have led the way nationally in the use of rainwater. When the South Australian Government introduced the Permanent Water Conservation Measures in late 2003 and the tighter Level 3 Enhanced Water Restrictions in 2007, South Australian households responded in reducing their daily household water consumption by 16% between 2002-03 and 2003-04, and by 21% between 2006-07 and 2007-08.

For the period 2001 to 2010, South Australia's households also became more active in taking measures to save water indoors and in their gardens.

With recent good winter rains, the replenishment of state water stocks and some recent lessening of water restrictions, it will be interesting to watch their impact on future household water consumption and conservation habits, as reflected through SA Water and ABS surveys.


REFERENCES

ABS, Environmental Issues: Water Use and Conservation, March 2010 (cat. no. 4602.0.55.003)

SA Water Annual reports 2001-02, 2002-03, 2003-04,2004-05,2005-06,2006-07,2007-08,2008-09, 2009-10

SA Water Annual Reports 1998-99, 1999-2000,2000-01- provided by SA Water on request

SA Water, Level 3 Enhanced Water Restrictions, Water for Good Annual Statement 2010, http://www.waterforgood.sa.gov.au/