Imagining sustainable cities


Sustainability, as I define it, is the ability for a system to continue indefinitely for a prolonged period of time without reducing the amenity or the resources that maintain it. Put this way it might seem to be a form of perpetual motion that is unattainable, however the natural systems of the rain forest have achieved just that and it is on this model that we must base our future. Every waste must become a resource.

Currently we have an exploitative system that measures its success in terms of GDP, namely throughput and the speed with which resources are consumed – this is not a sustainable economy and it is likely to run head first into the wall of ecological disaster.

Thanks to Peter Nicholson at the Australian

Thanks to Peter Nicholson at the Australian

Every city is reliant on adjacent catchment areas for its water supply and must carefully maintain and protect of them. Much of our food supply is transported long distances using fossil fuels that pollute and contribute to rising atmospheric CO2. This will need to change to a non-polluting form of transport and/or reinvigorated local food production.

Current broad acre farming methods damage the land and use large amounts of fertilisers and chemical weed and pest controls. This must be tackled in order to develop a sustainable culture. So to metamorphose our current population centres into sustainable cities will require a major commitment from all areas and levels of society.

We have started looking at our buildings in terms of energy and water efficiency and there are two commercial buildings in Melbourne that aim for sustainability. One of them, 60L in Carlton, is complete, operating and currently undergoing evaluation. The design incorporates passive heating and cooling with computerised automatic control of exhaust and ventilation louvres. It includes rainwater harvesting and purification and onsite sewage treatment with recycled water being fed back through the toilet cisterns.
It has a roof garden, lockers and showers on every floor and bicycle parking at ground level but no car parking. It was built without a cost premium and is fully tenanted.

The second building, the Melbourne City Council new office building, is still under construction and has pushed the boundaries further, including sewer mining, improved use of heat chimney exhausts and computer controlled ventilation to allow heat purging during the night. External vegetation will help to control heat gain. These are the positive signs that we should encourage and follow.

So can we imagine a sustainable city?

First we must reduce or eliminate car ownership. Again Melbourne is taking its first hesitant steps in this direction as car sharing firms begin establishing their presence in the inner city areas. The development of regular, frequent, safe and cheap public transport is important and needs to occur prior to increased population densities, these changes will lead to a city with clean air and safe roads with wide footpaths and nature strips.

With reduced car numbers, parking spaces and car parks can be freed up allowing more space for garden allotments and recreation areas. Increased foot traffic will increase the number of casual interactions between residents, consequently reducing alienation and strengthening the neighbourhood community and sense of connection.

Then there is the question of population density. Should we encourage increased density with all the benefits and problems that it brings or should we aim for a more open structure which might encourage the home garden production of food but brings with it the risk of developing yet more dormitory suburbs, the destruction of fertile land, bush and loss of biodiversity? It is my opinion that higher density cities could be the most effective answer.

A by-product of high density building is the heat island effect which results from the concentration of heat absorbent structures and surfaces plus the impact and activities of the population. This effect can be offset quite effectively by using vegetated roof cover and roof gardens to reduce heat gain. This in turn will reduce the peak run off during rain storms and promote a more even interior temperature range thus reducing the demand for heating and cooling.

As we take our first hesitant steps on this road towards sustainability it is revealed as a less extravagant but perhaps more satisfying existence with improved air quality, less chemical pollution, more greenery and a workplace located close to the residential area, while the alternative seems to offer more consumer goods, more pollution and more debt coupled with land degradation, loss of forests, depleted rivers, escalating resource conflicts…… surely the choice is the proverbial ‘no-brainer’.

Launched in 2004, New Matilda is one of Australia's oldest online independent publications. It's focus is on investigative journalism and analysis, with occasional smart arsery thrown in for reasons of sanity. New Matilda is owned and edited by Walkley Award and Human Rights Award winning journalist Chris Graham.