State of the Environment

2006

Human settlements

Theme commentary
Professor Peter W. Newton, Swinburne University of Technology
prepared for the 2006 Australian State of the Environment Committee at CSIRO, 2006

Settlement induced pressures on built and natural environments

Resource consumption

Human settlements are key centres for the consumption of material resources. The convergence of road, rail, air, water, electricity and gas networks are evidence of this. There are three major sectors of material resource consumers in each urban centre:

Each is the subject of increasing study concerning the resource use efficiencies. For built environments, the focus is on issues relating to the scale and form of settlement (such as density, compactness and infrastructure effectiveness); for manufacturing industries, the focus is on energy and water intensities, material reuse, recycling and re-manufacturing and the environmental signatures for manufactured products and materials (ecolabelling); for households the focus is on the potential for behaviour and lifestyle change to reduce the demand on natural resources.

A stocks and flows perspective

The first comprehensive materials stocks and flows study undertaken in Australia revealed a total material flow of about 180 tonnes per person per year (Foran and Poldy 2002), a figure that is more than twice that of any other OECD country. This high figure is due to Australia’s significant and continuing reliance on a minerals export industry and the fact that mining overburden and waste is included in the total (refer to Newton et al. 2001, pp. 39–41).

For this report, Lennox and Turner (2005) have attempted to measure material stocks and flows for three urban regions in Australia for 1991 and 2001: Goulburn, the mid-north coast of New South Wales and South East Queensland. As a result of unreliable and missing data for 1991, and the data problems associated with smaller regions, only a 2001 material flows profile  of South East Queensland is available (Figure 3). The key insights provided by this study are as follows:

Figure 3: Resource stocks and flows – inputs to and outputs from South East Queensland.

Figure 3: Resource stocks and flows - inputs to and outputs from South East Queensland

Source: Lennox and Turner 2004

Energy

Energy use is a major environmental issue for Australia as a result of the contribution that it makes to the global generation of greenhouse gases through exports of fossil fuels—coal, oil and natural gas—as well as Australia’s continuing reliance on fossil fuels at a domestic level.

Primary energy consumption is forecast to increase by 48 per cent to reach 7544 petajoules by the year 2019; this is an average rate of increase of 2.2 per cent per year. It is significantly above the expected rate of population increase, and it is driven by the continued growth in per capita consumption and economic growth (Table 2). This is despite a forecast reduction in energy per gross domestic product, which reflects an expectation of a decline in energy intensity that is due to increasing energy efficiencies (Productivity Commission 2005), new energy technologies (ABARE 2005), and a shift in the structure of the economy towards less energy intensive sectors.

Table 2: Energy use in Australia (more information on this topic) 
  Energy consumption
(PJ)		 Estimated Resident Population
(000)		 GDP*
$m		 Energy use per capita
(GJ per capita)		 Energy use per unit GDP
(GJ per $m
1997-98 4777.6 18711.3 633353.0 255.3 7543.3
1998-99 4884.7 18925.9 666921.0 258.1 7324.3
1999-00 4971.0 19153.4 692264.0 259.5 7180.8
2000-01 5034.1 19413.2 706109.0 259.3 7129.4
2001-02 5110.8 19641.0 733647.0 260.2 6966.3
2002-03 5215.1 19872.6 756170.0 262.4 6896.7
2003-04 5345.7 20111.3 783593.0 265.8 6822.0

* Reference Year 2002-2003

Source: Donaldson (2004, Table B), ABS (2005a), ABS (2004)

A projected switch—albeit small—to renewables and natural gas over the next 15 years  is expected to be one cause of lower greenhouse gas emissions than would be expected under a business-as-usual projection. Key factors in the sluggish growth in this key area are a combination of the relative cost of renewables compared with fossil fuels, the Australian Government’s relatively modest 2020 mandatory renewable energy target, and the set of barriers associated with the transition of Australia’s different industrial sectors to renewables (such as better uptake in the residential sector versus air or surface transport).

Electricity generation is a leading consumer of energy in Australia. Its continuing high growth rates reflect the relatively low cost of electricity; the average price of electricity was 9.18 cents per kilowatt hour during 1994–95 to 2003–04 (ESAA 2002, 2005). There is scope for the greater energy efficiencies that need to be sought (Productivity Commission 2005), especially in energy conversion.

Energy conversion industries (such as electricity generation) provide energy inputs to other industries, and this is reflected in tables of final energy consumption  (also see Figure 4). Transport emerges as the dominant sector, with over 40 per cent of final energy consumption. This is significant, and it is approximately 25 per cent above that of the European Union, Japan and United States (Awano 2003). By way of contrast, energy consumption by buildings has been significantly lower in Australia, which is in part a reflection of lower demands for space heating due to a relatively benign climate. Increasing demand for air conditioners may alter this.

Figure 4: Australia’s energy consumption by sector 1991–92 and 2001–02 Figure 4: Australia's energy consumption by sector 1991-92 and 2001-02

Source: Donaldson (2004, Table B1)

Energy and the built environment

Many of the issues regarding energy consumption are sectoral in nature, as is indicated above. A more challenging question continues to centre on identifying spatial or settlement-related factors that are linked to energy use.

Rural-urban variation

An analysis of household expenditure data by Lenzen (1999) revealed that people in rural areas used about 20 per cent less energy than people in metropolitan areas, which is largely explained by differences in household incomes and spending power. Patterns of energy consumption in Sydney were also strongly correlated with income. Moreover, there was no evidence that per capita energy requirements saturate or plateau over the income range used in the study (Lenzen, et al. 2004).

Urban form variation

A study undertaken by Newton (1997, p. 2000) for AATSE (1997, pp. 177–78) indicated that compact cities represent the most fuel efficient of all urban forms, with over 40 per cent less transport fuel consumption than a dispersed form. The urban consolidation policies now operating in Australia’s capital cities are encouraging less sprawl and more compact styles of development, but they are the subject of debate about the perceived benefits in areas other than resource consumption.

Building form variation

The increased construction of more medium and high density forms of housing in Australia’s cities over the past 10–15 years raises questions of the relative energy efficiencies of different forms of housing (Miller and Ambrose 2005; Newton et al. 2000; Holloway and Bunker, 2002; Troy et al. 2002). Results from the Miller and Ambrose study in South East Queensland revealed that medium-density housing performed two to three times better than detached housing in terms of operating energy; high rise was not quite as energy efficient as medium density due to the general lack of cross-ventilation.

Energy efficiency remains a key policy interest (Productivity Commission 2005). Recent initiatives that have attempted to reduce the amount of residential energy use include the introduction of more energy efficient appliances, and energy-focused programmes relating to building design. The latter include minimum operating energy performance requirements (Building Code of Australia 2004 ) and state and territory government building energy rating schemes . The impact of insulation would appear to be greatest on energy efficiency, with little change emerging for water heating, space heating and lighting. Meanwhile, the growth in installation of air conditioners is rapidly accelerating, reflecting the continued inadequacy of housing design  for Australia’s climate and occupant preferences for thermal comfort (Tucker et al. 2002).

Water

The manner in which each urban region in Australia addresses its water security arrangements—how future demand is managed in the context of available supply options—tends to be specific to the unique biophysical and socio-economic circumstances of each region. A high level national perspective is, however, attempted in the sections that follow.

Urban water supply

Growth of human settlement in Australia called for a more reliable supply of water than was available from often highly variable river flows (McMahon et al. 1992). The construction of dams allowed for the diversion and storage of river flow and the creation of a more reliable water resource. It also ushered in the ‘linear’ model of urban water systems that has continued up until the present—distribution of water from central storage areas to consumers and discharge of wastewater (with varying levels of treatment) to receiving waters.

Australia now has over 80 major dams (with capacities over 100 gigalitres), most of which were constructed after the second world war—a period of major population and industrial growth (ABS 2004c). As the environmental consequences of reducing river flow have become known, only one major dam has been constructed since 1991. In April 2005, the Queensland Government allocated $150 million to build the 100 000 megalitre Wyaralong dam, west of the Gold Coast, to satisfy the water needs of an expected extra one million residents in the region.

With the exception of Perth, which has the largest potable groundwater supply of all Australian cities (supplying 60 per cent of present needs), water from aquifers currently do not feature significantly as a key source of drinking water in Australia’s cities; but this is likely to change as surface water becomes scarcer.

Currently, there are three networks that provide water services to urban communities—the drinking (or potable) water supply system, the sewerage (or wastewater) system, and the drainage and stormwater system.

Mains water accounts for 98 per cent of water provided to the capital cities; it is less important for other urban settlements, with mains providing only 86 per cent of their water. For both, the method of supply has been relatively fixed for some time. This is to a large extent due to the capital-intensive nature of these systems, with a long (100+ years) asset life. It is also due to the fact that satisfaction with water quality  is relatively high, and has been increasing. The Australian Drinking Water Guidelines  should continue to drive improvements in this area.

In 2001–02, nine per cent of Australia’s sewage effluent was being recycled for reuse, with higher rates of reuse in rural Australia (Radcliffe 2003, p. 212). Apart from Adelaide, the level of water recycling  and reuse is currently very low across all capital cities, being well below the national average and virtually completely absent from the domestic sector because of the need for an additional ‘pipe’ into the system. Capture, treatment and use of stormwater—the realisation of ‘city as catchment’—is even less well developed.

Demand for water

After irrigated agriculture, households constitute the second largest water-using sector  in the economy. The amount of water used varies substantially across the capital cities, reflecting the variable operation of a mix of factors that include consumption-based pricing, demand management through a range of conservation measures (appliances and household behaviour), and water restrictions. The reductions in urban water consumption over the last 20 years have been significant in some cities but nationally the trend indicates increased per capita and per household water use. For example, in the seven years to 2000–01, water use increased from 95 to 115 kilolitres per person  (an average annual rate of three per cent).

In considering the consumption of water by Australian households, it is important to recognise its various uses. The available data at national, state and capital city levels  clearly indicate that between one-third and perhaps as much as 60 per cent of household water consumption in some urban centres is used outside the house , primarily on gardens—a significant contrast to the United Kingdom, which averages three per cent (WSAA 2003). This represents the area with the most significant potential for reduction in use. Perth’s domestic water use study indicated that usage of water by households living in multi-storey dwellings consistently averaged 250 litres per day. This is half that of the lowest daily usage of low income households in detached dwellings, and one-tenth of the highest daily usage by high income households (Water Corporation 2003).

The reduction in water use in toilets has been significant over the past ten years due to the introduction of dual flush toilets ; the next major gains are likely to involve the use of recycled water for flushing and, ultimately, the waterless toilet. Of particular note in the Perth study is that the water savings achieved through the regulation of dual flush toilets (as well as other water conservation and labelling schemes) have been ‘lost’ to increased washing machine use. This is a classic example of the rebound effect that bedevils many areas of environmental conservation and efficiency.

Future demand and supply

Residents of Australian cities have responded positively to water demand management measures. In all cities, water consumption has either stabilised or declined from the peaks achieved around the early 1980s.

The key issue for the future is whether each city has a sustainable yield  that is capable of meeting projected increases in population and industry. Calculations by the Water Services Association of Australia (unpublished data) and summarised in the Data Reporting System suggest that water consumption in all capitals, with the exception of Canberra, will have exceeded their sustainable yield by 2030.

These projections could be further exacerbated if current climate change scenarios for Australia materialise (Hennessy 2003). Decreased rainfall in the south-west of Western Australia has seen the total annual inflow to Perth dams decline from an average of 338 gigalitres in 1911–74 to 177 gigalitres in 1975–96, with only 120 gigalitres of inflow in 1997–2003). Rainfall has also declined in much of south-eastern Australia, with near-record low water levels in dams in much of the region during the prevailing 2002–05 drought.

The challenge of urban water systems

Unaccounted-for-water

While Australia compares favourably with overseas countries, a loss of 142 litres per property per day from leakages represents a challenge to the Australian water industry. Responses will emerge from improved monitoring and pipe maintenance systems (Burn et al. 2004).

Efficient water use

Voluntary water conservation rating and labelling schemes pioneered by Standards Australia and the Waters Services Association of Australia  are now being superseded by state, territory and Australian government mandatory labelling schemes  to ensure all key water using appliances are labelled.

Water pricing

Water pricing has been the cornerstone of demand management (WSAA 2003), as property-based pricing has given way to consumption-based pricing. The impact of pricing on demand has been significant across Australia’s cities. Clearly, the various household uses of water will have different price elasticities, with indoor water use being more inelastic than outdoor use. Is this perhaps a basis for dual metering?

Integrated urban water management

The various components of the urban water cycle have always been considered independently: potable water is extracted from a catchment to meet water demands; wastewater is collected, treated and discharged; and stormwater is collected and discharged. What is now apparent to water authorities is the unsustainability of this system, and that the interdependencies between the elements of the urban water cycle need to be recognised and harnessed. Integrated urban water management has been proposed by CSIRO (2002) as a more holistic approach to providing water, wastewater and stormwater to urban communities. For Australia’s major capitals, stormwater and wastewater—mostly disposed to receiving waters—represent a ‘resource’ to be tapped as they currently generate a volume that is 1.5 times in excess of present water use.

Capturing all parts of the water cycle involves consideration of:

The challenge of healthy waterways: from catchment to coast

Australian settlement is heavily concentrated around its coastline, rivers and estuaries and the range of activities associated with urban development have contributed to degradation of all water systems.

Waste

Improving the ecological sustainability of Australia’s human settlements involves minimising waste outputs by using a mix of processes that are applicable in the domestic and industrial sectors.

The volume of solid waste disposed to landfill across Australia remains high, at around one tonne per person per year (ABS 2003b, p. 641). Between 1996–07 and 2002–03, New South Wales, Queensland, South Australia and the ACT reduced the amounts of waste they generated; Victoria and Western Australia have experienced increases.

Across the three main categories of solid waste  disposed to landfill, municipal waste tends to be the highest (40 per cent), followed by commercial and industrial waste (37 per cent). There is a range of hazardous wastes  disposed across Australia. Those disposed by households reveal a pattern of disposal that is comparable between residents of capital cities and the rest of Australia (Table 3). Of particular concern, however, is the extent to which hazardous household wastes are currently disposed of in combination with municipal garbage.

Table 3: Solid landfill waste quantities in Australia by states and territories for 2002–03
Sector Amount of waste to landfill (‘000 tonnes)
NSW Vic Qld SA WA Tas NT ACT
Domestic and municipal 1657 2133 1108 na 741 na na 82
Commercial and industrial 2358 combined
2790		 522 na 420 na na 98
Construction and demolition 1193 200 na 1525 na na 27
Other - 545 986 na - na na -
Total (b) 5208 5467 2815 1252 2696 na na 207

Source: ABS (2004g, p. 15)

Resources from waste: recycling in Australia

Australia’s rate of recycling of solid waste  has been estimated at 36 per cent, ranging from a high of 58 per cent in the ACT (Canberra) to a low of 18 per cent in Tasmania.

Household involvement in the recycling process  is high and now almost universal within Australia’s cities. Recycling by households is lower in areas outside the capital cities, due to logistics and the costs associated with collection and transport from rural areas to processing plants. Reuse of waste, by way of contrast, is higher among non-metropolitan households (space for storage and home workshops may be a factor here).

Recycling is restricted to a relatively narrow band of products and materials. The data on which this assessment is based are almost a decade old, and they reveal an apparent inertia in Australia to initiatives that attempt to make key transitions in Australia’s economy—cradle-to-cradle manufacturing, regional eco-industrial development, product stewardship, and creating wealth from waste. Providing data that relate to household recycling behaviour is no substitute for detailed information on waste streams and diversion rates. This becomes particularly apparent when Australia’s performance in recycling is put in international context.

Waste to energy

An international comparison of solid waste disposal methods (Batten 2002) reveals that landfill accommodates 96 per cent of Australia’s waste; this compares poorly with 70 per cent in the United States (where 16 per cent is incinerated) and 50 per cent in Sweden (where 45 per cent is incinerated). Technological improvements have made incineration cleaner and the process could be used to generate electricity, reducing Australia’s use of fossil fuels. Arguments against high temperature incineration—especially for hazardous wastes—are that such facilities reinforce the behaviour of waste creation and may also impede the development and introduction of new substitute products (Beder 1990).

When municipal waste is dumped in landfill, much of the organic component is naturally converted by bacteria to methane. In the year 2000, almost 15 million tonnes of methane was emitted to the atmosphere—contributing three per cent of Australia’s net greenhouse gas emissions  (AGO 2002 cited in ABS 2003b, p. 145). It is estimated that approximately 80 per cent of Australia’s municipal solid waste could be used for the production of energy. This represents a source of approximately 50 gigajoules annually, excluding the total potential from existing landfill sites (ABS 2003b, Aquatech 1997). Despite this potential, Australia is one of the few developed nations that does not have a well-established waste-to-energy industry. This is due, in large part, to (low) pricing of landfill disposal and electricity.

The scope for eco-industrial development in Australia

Despite developments in resource recovery, millions of tonnes of materials continue to be disposed to landfill, accounting for the majority of waste that is generated in Australia. This linear pattern of resource flows, based on single-use and then disposal is unsustainable in the long term and it generates unwanted social, environmental and economic impacts.

Some approaches that are employed to address these impacts (to a greater or lesser extent) include:

Urban systems and processes

Since 2001, most state governments have released strategic plans for their capital cities that represent blueprints for development and that are loosely directed towards achieving a range of triple-bottom-line performance outcomes. Key among these for the faster-growing cities of Brisbane , Sydney , Melbourne  and Perth  are policies designed to minimise the sprawl of outer suburbia and to encourage higher density residential development around key activity centres and routes served by public transport. In addition there are a range of sector-specific government policies that require implementation within cities and that can directly as well as indirectly shape the form and function of cities. These relate to targets for water use and water quality, energy use, wastewater recycling, solid waste disposal to landfill, protecting catchments, and green wedges public transport usage, and others.

Issues of urban form and density

Between 1996 and 2001 levels of population density have increased in all capital cities, but most noticeably in the larger cities and, within that, predominantly in the inner city municipalities (the cities of Melbourne, Sydney, and Perth) where high rise development dominates (see Table 4).

Table 4: Selected occupied private dwellings* Australia, 2001
Population centre
(grouped by size)		 Separate houses High density housing Total Dwellings#
(’000)
Percentage of dwellings Change in number of dwellings
(%)		 Percentage of dwellings Change in number of dwellings
(%)
2001 1991–2001 2001 1991–2001 2001
Capital cities 72.4 16.1 26.7 36.2 4 453.4
   Sydney 63.7 10.2 35.5 36.5 1 438.4
   Melbourne 74.5 13.9 24.7 36.0 1 243.4
   Brisbane 80.6 25.9 18.3 73.5 601.1
   Adelaide 75.5 13.5 24.0 13.9 430.2
   Perth 77.9 26.1 21.5 30.5 511.2
   Hobart 83.1 15.4 16.2 8.2 76.1
   Darwin 62.6 32.8 29.8 55.4 38.2
   Canberra 76.9 18.0 22.8 49.6 114.7
Other large cities 76.8 40.0 20.8 71.5 1 257.9
Country areas 86.5 7.0 8.5 -0.1 1 361.0
Australia 75.9 17.5 22.2 37.2 7 072.2

* Dwellings where the dwelling structure was not stated were excluded prior to the calculation of percentages
# Includes other dwellings

Source: ABS (1991; 2001), cited in: ABS (2003e, p. 176)

A transition to higher levels of residential density within cities is seen as a means of achieving a number of key environmental objectives. Higher densities of urban development are associated with:

Despite these quantified environmental benefits of higher density residential development (versus detached housing), there continues to be debate in Australia over what are seen to be state and territory government ‘town cramming’ policies. Forster (2004, pp. 169–74) provides a recent summary of this debate. The most recent challenges to consolidation strategies have come from Birrell et al. (2005), who question the extent of demand for higher density forms of living—especially among generation X households entering the family formation phase and baby boomer households, the first several million of whom are about to turn 60 and their residential preferences are not known (particularly in relation to foregoing space). A second key area of criticism involves the negative impact that current residential infill policies and practices have had on neighbourhood character and amenity (see Lewis 1999). Key challenges here relate to inadequate regulation and guidelines, an absence of timely and rigorous assessment of development proposals, and continued separation of the planning and building (design) functions in government.

New industrial landscapes and the mega-metropolitan region

Australia’s current system of settlement reflects a century-long wave of transitions that have been accelerating over the past 50 years. Artefacts from each era are represented to some degree in the nation’s contemporary capital cities: the historical walking city around the port and central business district, the radial spokes of the transit city and its remnant manufacturing districts, the auto city highways and low density suburbs, and the emergent mega-metropolitan regions. The driving force of these transitions is grounded in technological change and the manner in which technical innovation is employed by society to create new industries, shape new urban infrastructures, produce new products and services for consumption, and generate new kinds of jobs (see Appendix 3; Milani 2000, Vellinga and Herb 2003, Florida 2002).

Industry-of-employment data reveal recent elements of these transitions (Appendix 4). What the analyses of the data reveal for the mega-metropolitan regions is maintenance in absolute levels of employment  in extractive industries, but a slight decline as a proportion of total workforce; slight numerical growth in manufacturing jobs, but a slight diminution of employment share. In other words, both extractive industries and manufacturing sectors continue to be significant contributors to the wider Australian economy. Growth in distributive and social services employment as a share of total has been negligible. Most growth is occurring in the producer services (information-centred) and personal services (consumption-centred) industries.

In twenty-first century Australia, the cities, and in particular the mega-metropolitan regions, are the major contributors to the nation’s economic activity . Capital cities generate about two-thirds of all economic activity: Sydney produces 23 percent of activity, Melbourne 18 per cent, then Brisbane and Perth at about seven per cent each and Adelaide at five per cent (Allen Consulting Group 2002;). Three-quarters of Australia’s economic activity emanates from the eight capital cities plus Geelong, Newcastle and Wollongong: these are classed by ABS (2004d) as ‘metropolitan Australia’. Australia’s regional centres are facing challenges in competing with the cities for the ‘new economy’ jobs. From 1995–06 to 2000–01, small business in capital cities increased by 6.4 per cent, but declined by one per cent in other parts of Australia (ABS 2004f). This exerts a circular and cumulative effect in the respective housing and retail (personal services) markets (Birrell and O’Connor 2000).

Figure 5: Percentage change in employment in four Mega-metro regions by industry sector (Singleman's Classification) 1991-2001

Figure 5: Percentage change in employment in four Mega-metro regions by industry sector (Singlemans Classification) 1991-2001

Source: Australian Bureau of Statistics (2003cd Table 15)

Consumption landscapes

Consumption is at the heart of modern capitalist economies, in which the market strives to convince a population that they must advance beyond a satisfaction of the ‘needs’ stage of materialism to a satisfaction of ‘wants’, the definition of which, in a sense, can be open-ended. Postwar suburbanisation was a highly successful attempt to tap into the needs of a growing population that had had demand for basic housing and civil infrastructure and transport suppressed as a result of the Depression and the Second World War (Forster 2004).

This sector of urban consumption continues to be stimulated in the early twenty-first century by advertising for larger houses, more appliances, and more cars, as well as a raft of personal products and services associated with leisure, entertainment, travel and other ‘wants’ (Australia is the tenth ranked country globally in terms of its annual spending on advertising). Hamilton et al. (2005) found that a significant proportion of current consumption is also found to be wasteful and the richer the household, the more is spent on wasted goods and services.

As already discussed in relation to water and energy (and, in later sections, for transport and housing), consumption increases with income. Forecasts of a doubling of living standards in Australia over the next 50 years (Guest and McDonald 2002, p. 13), together with an extra 6.5 million residents, suggest a formula for continued growth in total consumption, unless there is a shift to what Hamilton (2003) terms a post-growth society, with greater focus on rethinking and re-distributing work, reducing consumption, and reducing wastefulness (Milani 2000).

The trends of the past five to ten years indicate that, during a period of relatively high employment  and sustained high consumer confidence, per capita household consumption expenditure  has increased by 25 per cent from $19 000 per person in 1995–06 to $24 000 in 2003–04. During this period, Australians’ attitudes to environmental issues have nose-dived. In 1992, three-quarters of the population indicated an interest in or concern for environmental problems ; by 2004 the figure was 57 per cent. This is perhaps indicative perhaps of a shift towards a society that is more materialistic and less concerned with sustainability (ABS 2003b).