Overview
'Environmental impacts are concentrated where population is concentrated'

Human settlements are where we live. Cities, country towns and remote rural settlements all form our human environment. The impact that human society has on the environment relates to its size, production and consumption (which will influence, for example, the amount of waste produced), resource use, technology used to supply goods and services, and our effectiveness in preventing or repairing environmental degradation. To assess the impact that human settlements have on the environment we address the following topics: population and urban form, water and energy consumption, waste, and transport use.

South Australia's population is highly concentrated in urban areas. In 2001, South Australia's population was just over 1.5 million, with approximately 81% of the population living in the Adelaide and outer surrounding areas within an 80 kilometre radius of the Adelaide GPO. Population projections by Planning SA suggest that by 2016 this concentration of population will have increased to almost 83%.

Despite a slowing of population growth at the State level, the patterns of population growth vary widely within and between different regions. This results in a concentration of certain environmental impacts in particular regions, such as the detrimental effects of stormwater, atmospheric pollution and waste production.

Water supplied to the urban settlements of South Australia is extracted from the River Murray, surface water reservoirs (mostly in the Mount Lofty Ranges), groundwater in the South East, northern and western areas of the State and, more recently, extracted from the sea. Our reliance on the River Murray for urban water supplies, either as a direct or a supplementary source of water, is placing additional pressure on the River and adding to its degradation. In an average year, around two-thirds of Adelaide's water comes from the River Murray.

Adelaide's water consumption per capita is among the lowest when compared with other Australian capital cities, but is very high compared to world standards. Per capita mains water consumption in the Adelaide metropolitan area has remained steady since 1997/98.

South Australia's energy consumption is close to the national average and is rising each year. Ninety-eight per cent of all energy supplied in South Australia is derived from fossil fuels. Oil - primarily in the form of petrol used for transport purposes - remains our largest single source of energy, supplying around 47% of the State's energy needs. South Australia has made encouraging progress in the establishment of a renewable energy industry in recent years, with a number of windfarms constructed or approved for development.

In South Australia (as in much of the 'developed world') natural resources are used to make products or provide services and, as a result, waste is generated which is then typically disposed of rather than reused. Despite an increase in the number of people recycling, the amount of waste going to landfill is increasing. Around one tonne of solid waste per person went to landfill in the Adelaide metropolitan area in 2002. This is despite the fact that approximately 70% of the total waste discarded to landfill could be recycled and converted into valuable products, re-used or composted.

Transport is an essential component of human settlements. It influences settlement patterns and liveability, is essential for economic performance and provides opportunities for people to participate in social, economic and recreational activities. While transport provides a wide range of social and economic benefits, however it is a significant contributor to environmental pollution - such as air, water and noise pollution, greenhouse gas emissions and roadside litter.