vendredi 19 juillet 2013

Ecopolis: The emergence of 'regenerative cities'

Lorna Howarth examines a growing movement in urban planning that moves beyond preventative sustainable development to 'regenerative' development, aiming to counter some of the destruction urbanisation has wreaked on the planet....

Global statistics point towards an increasing exodus of people from the countryside into urban areas. Currently, just over 50% of humanity lives in cities, but the impact of these cities on the planet is devastatingly unsustainable. In an urbanizing world, we have to redesign our cities and their systems of resource use in order to survive.
Thankfully, Professor Herbert Girardet has spent much of his working life on this issue and has come up with the concept of ‘regenerative cities' that aims to set out a roadmap of transformation in the way cities function - and also offers hope that humanity's fate need not be one of resource wars, conflict and climate chaos.
I met up with Professor Girardet recently and we talked about how his work evolved. He told me of his travels in the Amazon in the 1980s, making documentaries about rainforest medicines, deforestation and disappearing tribal cultures;
"When I saw a huge stack of mahogany planks with ‘London' stamped on them being loaded on to a freighter at the port of Belem, I became acutely aware of how deeply the tendrils of cities infiltrated the planet".
This was one of many incidents that propelled him to co-found The World Future Council and work toward developing systems that would facilitate more sustainable patterns of resource use. One of the most notable of these is the introduction of Feed-In Tariffs which Professor Girardet and his colleagues from WFC initiated in the UK and Australia. This work drew on what Germany and Denmark had already done to generate ever increasing amounts of renewable electricity. Germany reached its 25% renewable energy target in 2012 and is on track to reach 35% by 2020 and 80% by 2050.
Groundbreaking as much of his work was, Girardet gradually came to realise that the concept of ‘sustainability' is no longer fit for purpose;
"Today there is much less to sustain than when the term was coined in the 1980s. We've exceeded the limits to growth on nearly every aspect of development. Sustainable development will not dig us out of the hole we find ourselves in. We have to start thinking in terms of regenerative development.This means working towards giving back to nature as much we take.
If we harvest crops from fields in the hinterlands of a city, we must return compost from organic waste. We must make regenerative energies into the main source of power supply. And as long as we carry on burning fossil fuels we must ensure that trees and soils absorb our C02 emissions. In hot countries we must capture the rainfall from city roofs to recharge groundwater tables. We must create living landscapes to create habitats for natural pollinators and predators.
If we think along these lines - trying to be as generous to nature as nature is to us - then we may have a chance of harmonising our relationship to our planetary home."
Girardet is no idealist or blue-sky thinking optimist. He is a realist who has seen first hand the hidden corners of the planet where the impact of humanity's consumption has devastated communities and ecosystems. He recalls the haunting words of a Kayapo Elder who, overlooking a smouldering landscape, asked "Why does the white man destroy everything? Where will my children live, what will they have to eat?" This plaintive question inspired Girardet to explore how humanity could begin to counter and repair this destruction.
So, what is a regenerative city - ‘Ecopolis'? It is one that relies primarily on local and regional food supplies; it is powered, heated, cooled and driven by renewable energy, and it reuses resources and restores degraded ecosystems. This is diametrically opposed to how many cities are currently run: they use resources without concern for their origins or destination of their waste products; they emit vast amounts of carbon dioxide without ensuring reabsorption and they consume huge amounts of meat produced mainly with imported feed, often from devastated rainforest regions.
In short, the concept of regenerative urban development aims to ensure that we implement comprehensive strategies for an enhancing, restorative relationship between an urbanising humanity and the ecosystems from which we draw resources for our sustenance. This is achieved by transforming the metabolism of the city from a linear throughput of resources to a circulating system, where resources are recycled, renewables are maximised and consumption and pollution is greatly reduced.
The good news is that there are more and more examples from around the world where the principles of regenerative development are being put into practice, and thanks in part to Professor Girardet's work as a ‘Thinker In Residence' in Adelaide ten years ago, South Australia has become a shining example. In Greater Adelaide, a city region of 1.2 million people, more than 26% of the city's electricity is produced by wind turbines and solar PV panels. There are over 200,000 houses in the city with photovoltaic roofs, making some of them into net electricity generators. Efficient energy use is now mandated for all municipal buildings, reducing their carbon emissions by up to 60%. There has been a large-scale retrofit throughout the city to ensure high standards of energy efficiency in people's homes, and a new-build solar village with 110 homes has been designed to the highest sustainable standards. These initiatives have reduced overall carbon emissions from the city by 15% since 2003.
In and around Adelaide, nearly 3 million trees have been planted on 2,000 hectares of land, providing carbon dioxide absorption services, as well as countering soil erosion and increasing biodiversity. An ambitious zero-waste policy has been implemented that has enabled the production of 180,000 tonnes of compost a year, made from the city's organic waste. This is then used to improve the fertility and soil structure of 20,000 hectares of land near the city that produces most of the fruit and vegetables the populous consumes. This land is also irrigated with reclaimed waste-water. And to top all of this, Adelaide has the world's first solar powered bus service!
Adelaide shows how cities can be planned and retrofitted for resilience and environmental regeneration, and a positive spin-off is the emergence of a new, green economy with the creation of thousands of new, long-term jobs.
However, in order for any of this to take place, city authorities and institutions have to be convinced of the benefits of changing course and focusing on regenerative development principles. This can be an uphill struggle and is made more difficult where the privatisation of urban services such as transport, water, energy and waste management has reduced their capacity to create well-integrated urban systems.
But these problems are not insurmountable. Even in ancient city regions such as Seville in Spain, regenerative principles can be implemented. On the outskirts of Seville there are three concentrating solar power stations that produce 183 megawatts of electricity - enough to supply most of the city's electricity needs.
Waste management is an absolutely key concept in regenerative cities as it not only reduces waste going to landfill, but helps capture organic waste for composting, increases the recovery of recyclables and facilitates the growth of small businesses that use the ‘waste' as raw materials.
For instance, since 2006 the city of Oakland, California, has worked to implement a strategic target of Zero Waste, and has already achieved an incredible 75% reduction in waste dumping. This was accomplished by pursuing ‘upstream' redesign strategies to reduce the volume and toxicity of products and materials, and by improving ‘downstream' reuse and recycling of end-of-life products including the re-use of products and materials, to stimulate local economic and workforce development.
Local food production is also a key element of regenerative cities. Currently many cities import their foodstuffs from all over the world, resulting in huge and highly unsustainable ecological footprints.
Cuban cities however, due to political circumstances (most notably the collapse of the Soviet Union in 1989 and the US trade embargo) had to become food self-sufficient by necessity. There are now over 35,000 hectares of urban land in Cuba where over 117,000 people work, growing food for the country's citizens.Cuba's urban agriculture programme aims to provide everyone with at least 300 grams of fresh vegetables per day, a figure deemed appropriate by the FAO for optimum health. Havana in particular is a world leader in urban food production with ‘organoponico' gardens throughout the city.
Surprisingly, urban agriculture is also burgeoning in US cities such as New York and Detroit. And in China, a long tradition of urban agriculture continues as government policy. In Shanghai 1.3 million tonnes of vegetables are grown on peri-urban land, meeting 60% of the city's needs.
Professor Girardet is eloquent and animated on the subject of regenerative cities. He believes that cities, at best, are important global assets and can be the places where solutions to the world's environmental and climate problems can be effectively implemented. It is in cities where creativity flourishes and people can interact and engage vigorously in the search for solutions.
But in order for regenerative cities to become a reality around the world, local, regional, national and transnational ‘enabling policies' are required to help people to transform their cities. Adelaide is one of an ever growing number of cities that have taken bold steps towards this vision and have set precedents that can be replicated and further developed elsewhere.
We have to change course and to adapt and thrive in ‘Ecopolis' if humanity and the biosphere are to survive.
Lorna Howarth is a writer and environmentalist. 

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